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18 pages, 5017 KiB  
Article
Thermodynamic Study on Biomimetic Legionella gormanii Bacterial Membranes
by Katarzyna Pastuszak, Marta Palusińska-Szysz, Agnieszka Ewa Wiącek and Małgorzata Jurak
Molecules 2024, 29(18), 4367; https://doi.org/10.3390/molecules29184367 (registering DOI) - 14 Sep 2024
Viewed by 187
Abstract
The presented studies were aimed at determining the interactions in model membranes (Langmuir monolayers) created of phospholipids (PL) isolated from Legionella gormanii bacteria cultured with (PL + choline) or without (PL − choline) choline and to describe the impact of an antimicrobial peptide, [...] Read more.
The presented studies were aimed at determining the interactions in model membranes (Langmuir monolayers) created of phospholipids (PL) isolated from Legionella gormanii bacteria cultured with (PL + choline) or without (PL − choline) choline and to describe the impact of an antimicrobial peptide, human cathelicidin LL-37, on PL’s monolayer behavior. The addition of choline to the growth medium influenced the mutual proportions of phospholipids extracted from L. gormanii. Four classes of phospholipids—phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), cardiolipin (CL), and their mixtures—were used to register compression isotherms with or without the LL-37 peptide in the subphase. Based on them the excess area (Ae), excess (ΔGe), and total (ΔGm) Gibbs energy of mixing were determined. The thermodynamic analyses revealed that the PL − choline monolayer showed greater repulsive forces between molecules in comparison to the ideal system, while the PL + choline monolayer was characterized by greater attraction. The LL-37 peptide affected the strength of interactions between phospholipids’ molecules and reduced the monolayers stability. Accordingly, the changes in interactions in the model membranes allowed us to determine the difference in their susceptibility to the LL-37 peptide depending on the choline supplementation of bacterial culture. Full article
(This article belongs to the Special Issue Exclusive Feature Papers in Physical Chemistry, 2nd Edition)
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Figure 1

Figure 1
<p>The <math display="inline"><semantics> <mrow> <mi>π</mi> <mo>−</mo> <mi>A</mi> </mrow> </semantics></math> isotherms obtained for the individual phospholipid classes: PC, PE, PG, CL, and the PL mixtures isolated from <span class="html-italic">L. gormanii</span> bacteria cultured on a medium without (−choline) and with the addition of exogenous choline (+choline) at 20 °C and 37 °C, in the (<b>a</b>,<b>b</b>) absence or (<b>c</b>,<b>d</b>) presence of the LL-37 peptide.</p>
Full article ">Figure 2
<p>The <math display="inline"><semantics> <mrow> <msubsup> <mrow> <mi>C</mi> </mrow> <mrow> <mi>S</mi> </mrow> <mrow> <mo>−</mo> <mn>1</mn> </mrow> </msubsup> <mo>−</mo> <mi>π</mi> </mrow> </semantics></math> dependencies obtained for the individual phospholipid classes: PC, PE, PG, CL, and the PL mixtures isolated from <span class="html-italic">L. gormanii</span> bacteria cultured on a medium without (−choline) and with the addition of exogenous choline (+choline) at 20 °C and 37 °C, in the (<b>a</b>,<b>b</b>) absence or (<b>c</b>,<b>d</b>) presence of the LL-37 peptide.</p>
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<p>The excess area <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>A</mi> </mrow> <mrow> <mi>e</mi> </mrow> </msub> </mrow> </semantics></math>, depending on the surface pressure <math display="inline"><semantics> <mrow> <mi>π</mi> </mrow> </semantics></math>, obtained for the “−choline” and “+choline” multi-class monolayers at 20 °C and 37 °C, in the (<b>a</b>) absence or (<b>b</b>) presence of the LL-37 peptide.</p>
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<p>The excess Gibbs energy of mixing <math display="inline"><semantics> <mrow> <mo>∆</mo> <msub> <mrow> <mi>G</mi> </mrow> <mrow> <mi>e</mi> </mrow> </msub> </mrow> </semantics></math>, depending on the surface pressure <math display="inline"><semantics> <mrow> <mi>π</mi> </mrow> </semantics></math>, obtained for the “−choline” and “+choline” multi-class monolayers at 20 °C and 37 °C, in the (<b>a</b>) absence or (<b>b</b>) presence of the LL-37 peptide.</p>
Full article ">Figure 5
<p>The total Gibbs energy of mixing <math display="inline"><semantics> <mrow> <mo>∆</mo> <msub> <mrow> <mi>G</mi> </mrow> <mrow> <mi>m</mi> </mrow> </msub> </mrow> </semantics></math>, depending on the surface pressure <math display="inline"><semantics> <mrow> <mi>π</mi> </mrow> </semantics></math>, obtained for the “−choline” and “+choline” multi-class monolayers at 20 °C and 37 °C, in the (<b>a</b>) absence or (<b>b</b>) presence of the LL-37 peptide.</p>
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<p>Possible types of interactions between the phospholipid (PL–PL) molecules in the <span class="html-italic">L. gormanii</span> model membranes, where PC—phosphatidylcholine (cyan cylinder); PE—phosphatidylethanolamine (purple cone); PG—phosphatidylglycerol (pink truncated cone); CL—cardiolipin (blue truncated cone); <math display="inline"><semantics> <mrow> <mo>↔</mo> </mrow> </semantics></math> repulsion; <math display="inline"><semantics> <mrow> <mo>→</mo> <mo>←</mo> </mrow> </semantics></math> attraction; <math display="inline"><semantics> <mrow> <mo>⇔</mo> </mrow> </semantics></math> steric effects.</p>
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<p>Possible types of interactions between the phospholipid and peptide (PL-PEPTIDE) molecules in the <span class="html-italic">L. gormanii</span> model membranes, where PC—phosphatidylcholine (cyan cylinder); PE—phosphatidylethanolamine (purple cone); PG—phosphatidylglycerol (pink truncated cone); CL—cardiolipin (blue truncated cone); LL-37—cathelicidin (red-pink molecule); <math display="inline"><semantics> <mrow> <mo>↔</mo> </mrow> </semantics></math> repulsion; <math display="inline"><semantics> <mrow> <mo>→</mo> <mo>←</mo> </mrow> </semantics></math> attraction.</p>
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20 pages, 4932 KiB  
Article
Parvovirus B19 Infection Is Associated with the Formation of Neutrophil Extracellular Traps and Thrombosis: A Possible Linkage of the VP1 Unique Region
by Bor-Show Tzang, Hao-Yang Chin, Chih-Chen Tzang, Pei-Hua Chuang, Der-Yuan Chen and Tsai-Ching Hsu
Int. J. Mol. Sci. 2024, 25(18), 9917; https://doi.org/10.3390/ijms25189917 (registering DOI) - 13 Sep 2024
Viewed by 300
Abstract
Neutrophil extracellular traps (NETs) formation, namely NETosis, is implicated in antiphospholipid syndrome (APS)-related thrombosis in various autoimmune disorders such as systemic lupus erythematosus (SLE) and APS. Human parvovirus B19 (B19V) infection is closely associated with SLE and APS and causes various clinical manifestations [...] Read more.
Neutrophil extracellular traps (NETs) formation, namely NETosis, is implicated in antiphospholipid syndrome (APS)-related thrombosis in various autoimmune disorders such as systemic lupus erythematosus (SLE) and APS. Human parvovirus B19 (B19V) infection is closely associated with SLE and APS and causes various clinical manifestations such as blood disorders, joint pain, fever, pregnancy complications, and thrombosis. Additionally, B19V may trigger the production of autoantibodies, including those against nuclear and phospholipid components. Thus, exploring the connection between B19V, NETosis, and thrombosis is highly relevant. An in vitro NETosis model using differentiated HL-60 neutrophil-like cells (dHL-60) was employed to investigate the effect of B19V-VP1u IgG on NETs formation. A venous stenosis mouse model was used to test how B19V-VP1u IgG-mediated NETs affect thrombosis in vivo. The NETosis was observed in the dHL-60 cells treated with rabbit anti-B19V-VP1u IgG and was inhibited in the presence of either 8-Br-cAMP or CGS216800 but not GSK484. Significantly elevated reactive oxygen species (ROS), myeloperoxidase (MPO), and citrullinated histone (Cit-H3) levels were detected in the dHL60 treated with phorbol myristate acetate (PMA), human aPLs IgG and rabbit anti-B19V-VP1u IgG, respectively. Accordingly, a significantly larger thrombus was observed in a venous stenosis-induced thrombosis mouse model treated with PMA, human aPLs IgG, rabbit anti-B19V-VP1u IgG, and human anti-B19V-VP1u IgG, respectively, along with significantly increased amounts of Cit-H3-, MPO- and CRAMP-positive infiltrated neutrophils in the thrombin sections. This research highlights that anti-B19V-VP1u antibodies may enhance the formation of NETosis and thrombosis and implies that managing and treating B19V infection could lower the risk of thrombosis. Full article
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Figure 1

Figure 1
<p>Rabbit anti-B19 VP1u IgG induces NETs release. The dHL-60 cells treated with PMA, rabbit IgG, and rabbit anti-B19V-VP1u IgG (rabbit VP1u IgG), respectively, were stained with (<b>A</b>) SYTOX Green (left panel) and Hoechst 33342 (middle panel). The merged images were shown in the right panel, and arrows indicated the NETs. (<b>B</b>) The quantified results of SYTOX Green-positive signal. Three independent experiments were performed. The symbols * and # indicate significance (<span class="html-italic">p</span> &lt; 0.05) as compared to the control and rabbit IgG, respectively. <span class="html-italic">p</span>-value is calculated by one-way ANOVA followed by Tukey’s multiple comparison test.</p>
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<p>Inhibitory effect of NETs inhibitors (8-Br-cAMP, CGS21680, GSK484) on PMA and rabbit anti-B19V-VP1u IgG induced NETs. (<b>A</b>) The PMA and (<b>B</b>) rabbit anti-B19V-VP1u IgG (rabbit VP1u IgG) treated-dHL-60 cells in the presence of 8-Br-cAMP, CGS21680 or GSK484 were stained with SYTOX Green (left panel) and Hoechst 33342 (middle panel). The merged images were shown in the right panel, and arrows indicated the NETs. The quantified results of SYTOX Green-positive signals were shown in the lower panel. Three independent experiments were performed. The symbols *, #, and <span>$</span> indicate significance (<span class="html-italic">p</span> &lt; 0.05) as compared to the control, PMA, and rabbit anti-B19V-VP1u IgG, respectively. <span class="html-italic">p</span>-value is calculated by one-way ANOVA followed by Tukey’s multiple comparison test.</p>
Full article ">Figure 2 Cont.
<p>Inhibitory effect of NETs inhibitors (8-Br-cAMP, CGS21680, GSK484) on PMA and rabbit anti-B19V-VP1u IgG induced NETs. (<b>A</b>) The PMA and (<b>B</b>) rabbit anti-B19V-VP1u IgG (rabbit VP1u IgG) treated-dHL-60 cells in the presence of 8-Br-cAMP, CGS21680 or GSK484 were stained with SYTOX Green (left panel) and Hoechst 33342 (middle panel). The merged images were shown in the right panel, and arrows indicated the NETs. The quantified results of SYTOX Green-positive signals were shown in the lower panel. Three independent experiments were performed. The symbols *, #, and <span>$</span> indicate significance (<span class="html-italic">p</span> &lt; 0.05) as compared to the control, PMA, and rabbit anti-B19V-VP1u IgG, respectively. <span class="html-italic">p</span>-value is calculated by one-way ANOVA followed by Tukey’s multiple comparison test.</p>
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<p>Rabbit B19V-VP1u IgG increases citH3 and MPO expressions. (<b>A</b>) The representative results of the dHL-60 cells were treated with PMA, normal human IgG (NH IgG), human aPLs IgG, rabbit IgG, and rabbit anti-B19V-VP1u IgG (rabbit VP1u IgG), and the presence of NETs was measured by detecting the expressions of citH3 and MPO with flow cytometry (<b>B</b>) The quantified results of NETs. Three independent experiments were performed. The symbols *, <span>$</span>, and # indicate significance (<span class="html-italic">p</span> &lt; 0.05) as compared to the control, human IgG, and rabbit anti-B19V-VP1u IgG, respectively. <span class="html-italic">p</span>-value is calculated by one-way ANOVA followed by Tukey’s multiple comparison test.</p>
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<p>Rabbit anti-B19V-VP1u IgG increases citrullinated histone H3 (Cit-H3) expression. (<b>A</b>) Western blot analysis was used to detect the presence of Cit-H3 in dHL-60 cells treated with PMA, normal human IgG (NH IgG), human aPLs IgG, rabbit IgG, and rabbit anti-B19V-VP1u IgG (rabbit VP1u IgG). (<b>B</b>) The ratio of Cit-H3 amount relative to total H3. (<b>C</b>) The ratio of Cit-H3 amount relative to β-actin. Three independent experiments were performed. The symbols *, <span>$</span>, and # indicate significance (<span class="html-italic">p</span> &lt; 0.05) compared to the Control, NH IgG, and rabbit VP1u IgG, respectively. <span class="html-italic">p</span>-value is calculated by one-way ANOVA followed by Tukey’s multiple comparison test.</p>
Full article ">Figure 5
<p>Human aPLs IgG and rabbit anti-B19V-VP1u IgG increase ROS production. (<b>A</b>) The dHL-60 cells were treated with PMA, normal human IgG (NH IgG), human aPLs IgG, rabbit IgG, and rabbit anti-B19V-VP1u IgG (rabbit VP1u IgG), and the ROS level was measured in the presence of Dichloro-dihydro-fluorescein diacetate (DCFH-DA) with flow cytometry. The arrow indicates the proportion of DCF-positive cells, defined as cells exhibiting fluorescence intensity greater than the established threshold value. (<b>B</b>) The quantified results of mean DCF. Three independent experiments were performed. The symbols *, <span>$</span>, and # indicate significance (<span class="html-italic">p</span> &lt; 0.05) compared to the control, NH IgG, and rabbit VP1u IgG, respectively. <span class="html-italic">p</span>-value is calculated by one-way ANOVA followed by Tukey’s multiple comparison test.</p>
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<p>Rabbit anti-B19V-VP1u IgG promotes venous thrombosis in C57BL/6 mice with inferior vena cava ligation. (<b>A</b>) The representative images of thrombus from the mice treated with PBS, rabbit IgG, and rabbit anti-B19V-VP1u IgG (rabbit VP1u IgG). Sections of the thrombus stained with (<b>B</b>) H&amp;E, (<b>C</b>) anti-citrullinated histone H3 (Cit-H3), (<b>D</b>) MPO, and (<b>E</b>) CRAMP. Scale bar = 1 mm. The right panel showed the quantified results of thrombus weight, thrombus length, and positive cells of Cit-H3, MPO, and CRAMP signal. The symbol * and # indicate significance (<span class="html-italic">p</span> &lt; 0.05) as compared to the control and rabbit IgG, respectively. <span class="html-italic">p</span>-value is calculated by one-way ANOVA followed by Tukey’s multiple comparison test.</p>
Full article ">Figure 7
<p>Human aPLs and anti-B19V-VP1u IgG promote venous thrombosis in C57BL/6 mice with inferior vena cava ligation. (<b>A</b>) The representative images of thrombus from the mice treated with normal human IgG (NH IgG), human aPLs IgG, and human anti-B19V-VP1u IgG. Sections of the thrombus stained with (<b>B</b>) H&amp;E, (<b>C</b>) anti-citrullinated histone H3 (Cit-H3), (<b>D</b>) MPO, and (<b>E</b>) CRAMP. Scale bar = 1 mm. The right panel showed the quantified results of thrombus weight, length, and positive cells of Cit-H3, MPO, and CRAMP signal. The symbol * indicate a significance (<span class="html-italic">p</span> &lt; 0.05) as compared to the NH IgG. <span class="html-italic">p</span>-value is calculated by one-way ANOVA followed by Tukey’s multiple comparison test.</p>
Full article ">
26 pages, 3627 KiB  
Article
Unveiling the Performance of Co-Assembled Hybrid Nanocarriers: Moving towards the Formation of a Multifunctional Lipid/Random Copolymer Nanoplatform
by Efstathia Triantafyllopoulou, Diego Romano Perinelli, Aleksander Forys, Pavlos Pantelis, Vassilis G. Gorgoulis, Nefeli Lagopati, Barbara Trzebicka, Giulia Bonacucina, Georgia Valsami, Natassa Pippa and Stergios Pispas
Pharmaceutics 2024, 16(9), 1204; https://doi.org/10.3390/pharmaceutics16091204 - 13 Sep 2024
Viewed by 219
Abstract
Despite the appealing properties of random copolymers, the use of these biomaterials in association with phospholipids is still limited, as several aspects of their performance have not been investigated. The aim of this work is the formulation of lipid/random copolymer platforms and the [...] Read more.
Despite the appealing properties of random copolymers, the use of these biomaterials in association with phospholipids is still limited, as several aspects of their performance have not been investigated. The aim of this work is the formulation of lipid/random copolymer platforms and the comprehensive study of their features by multiple advanced characterization techniques. Both biomaterials are amphiphilic, including two phospholipids (1,2-dioctadecanoyl-sn-glycero-3-phosphocholine (DSPC), 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)) and a statistical copolymer of oligo (ethylene glycol) methyl ether methacrylate (OEGMA) and 2-(diisopropylamino) ethyl methacrylate (DIPAEMA). We examined the design parameters, including the lipid composition, the % comonomer ratio, and the lipid-to-polymer ratio that could be critical for their behavior. The structures were also probed in different conditions. To the best of the authors’ knowledge, this is the first time that P(OEGMA-co-DIPAEMA)/lipid hybrid colloidal dispersions have been investigated from a membrane mechanics, biophysical, and morphological perspective. Among other parameters, the copolymer architecture and the hydrophilic to hydrophobic balance are deemed fundamental parameters for the biomaterial co-assembly, having an impact on the membrane’s fluidity, morphology, and thermodynamics. Exploiting their unique characteristics, the most promising candidates were utilized for methotrexate (MTX) loading to explore their encapsulation capability and potential antitumor efficacy in vitro in various cell lines. Full article
(This article belongs to the Special Issue Polymer-Based Delivery System)
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Figure 1

Figure 1
<p>(<b>a</b>) The chemical structure of the random copolymer P(OEGMA950-co-DIPAEMA) synthesized by RAFT polymerization; (<b>b</b>) Graphic illustration of P(OEGMA-co-DIPAEMA)-1 or copolymer 1 and P(OEGMA-co-DIPAEMA)-2 or copolymer 2, respectively, with a different % comonomer ratio.</p>
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<p>Charts derived from DLS measurements at 25 °C: (<b>a</b>) The hydrodynamic radius (R<sub>h</sub>, nm); (<b>b</b>) the scattered intensity (I, kilocounts per second or kcps) of hybrid colloidal dispersions the day of their preparation, utilizing water for injection as the dispersion medium. The standard deviation (SD) is less than 10% in both diagrams. * Hybrid systems with more than one population; the predominant (higher intensity) one is presented in the graph.</p>
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<p>The hydrodynamic radius (R<sub>h</sub>, nm) of the hybrid colloidal dispersions in: (<b>a</b>) different dispersion media at body temperature (37 °C); (<b>b</b>) FBS:PBS biorelevant medium at different temperatures. The standard deviation (SD) is less than 10% in both diagrams. The DSPC:DOPC:1 9:1 hybrid system at 37 °C in both diagrams refers to a very high R<sub>h</sub> compared with the rest of the systems exceeding the scale of the graph.</p>
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<p>GP parameter vs. lipid composition of P(OEGMA<sub>950</sub>-co-DIPAEMA) hybrid systems at a steady lipid to polymer weight ratio (9:1).</p>
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<p>Cryo-TEM images of (<b>a</b>) P(OEGMA-co-DIPAEMA)-1. (<b>b</b>) P(OEGMA-co-DIPAEMA)-2 hybrid systems with different lipid compositions: (<b>i</b>) DSPC; (<b>ii</b>) DSPC:DOPC (9:1 weight ratio) and constant lipid to polymer ratio (9:1) or a constant lipid composition (DSPC) with different lipid to copolymer weight ratios: (<b>iii</b>) 7:3 and (<b>iv</b>) 5:5. The arrows represent the following: green color: spherical or irregularly shaped particles with distinct membrane; red color: “patchy” spherical- or pentagon-shaped vesicles; black color: rods; yellow color: small spherical particles.</p>
Full article ">Figure 6
<p>mDSC traces of (<b>a</b>) DSPC; (<b>b</b>) DSPC: DOPC (9:1 weight ratio) hybrid systems integrating P(OEGMA-co-DIPAEMA)-1 or -2 at different lipid to polymer weight ratios into aqueous medium.</p>
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<p>Thermodynamic evaluation of DSPC:P(OEGMA-co-DIPAEMA)-1 and -2 in an acidic environment (pH 4.5): (<b>a</b>) mDSC profiles; (<b>b</b>) (<b>i</b>) sound speed or (<b>ii</b>) attenuation vs. temperature from HR-US.</p>
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<p>(<b>a</b>) Size distributions from the DLS of DSPC:P(OEGMA-co-DIPAEMA)-2 hybrid systems incorporating MTX at two different lipid to polymer ratios, 9:1 (black line) and 5:5 (red line), on the day of their preparation; (<b>b</b>) the systems’ stability assessment (R<sub>h</sub> vs. time) under storage conditions (4 °C) for 21 days.</p>
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<p>Cell viability vs. different concentrations of MTX-DSPC:2 9:1 (blue line) and MTX-DSPC:2 5:5 (orange line) on (<b>a</b>) HEK293 and (<b>b</b>) HeLa cells. The concentration levels refer to MTX concentration, and the obtained data represent the means ± standard deviation from three experiments conducted in triplicates. The asterisks (*) in (<b>b</b>) correspond to p values of less than 0.05 (<span class="html-italic">p</span> &lt; 0.05) that are considered as statistically significant.</p>
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24 pages, 3272 KiB  
Article
Environmental Temperature Variation Affects Brain Lipid Composition in Adult Zebrafish (Danio rerio)
by Elisa Maffioli, Simona Nonnis, Armando Negri, Manuela Fontana, Flavia Frabetti, Anna Rita Rossi, Gabriella Tedeschi and Mattia Toni
Int. J. Mol. Sci. 2024, 25(17), 9629; https://doi.org/10.3390/ijms25179629 - 5 Sep 2024
Viewed by 340
Abstract
This study delves deeper into the impact of environmental temperature variations on the nervous system in teleost fish. Previous research has demonstrated that exposing adult zebrafish (Danio rerio) to 18 °C and 34 °C for 4 or 21 days induces behavioural [...] Read more.
This study delves deeper into the impact of environmental temperature variations on the nervous system in teleost fish. Previous research has demonstrated that exposing adult zebrafish (Danio rerio) to 18 °C and 34 °C for 4 or 21 days induces behavioural changes compared to fish kept at a control temperature of 26 °C, suggesting alterations in the nervous system. Subsequent studies revealed that these temperature conditions also modify brain protein expression, indicating potential neurotoxic effects. The primary aim of this work was to investigate the effects of prolonged exposure (21 days) to 18 °C or 34 °C on the brain lipidomes of adult zebrafish compared to a control temperature. Analysis of the brain lipidome highlighted significant alteration in the relative abundances of specific lipid molecules at 18 °C and 34 °C, confirming distinct effects induced by both tested temperatures. Exposure to 18 °C resulted in an increase in levels of phospholipids, such as phosphatidylethanolamine, alongside a general reduction in levels of sphingolipids, including sphingomyelin. Conversely, exposure to 34 °C produced more pronounced effects, with increases in levels of phosphatidylethanolamine and those of various sphingolipids such as ceramide, gangliosides, and sphingomyelin, alongside a reduction in levels of ether phospholipids, including lysophosphatidylethanolamine ether, phosphatidylethanolamine ether, and phosphatidylglycerol ether, as well as levels of glycolipids like monogalactosyldiacylglycerol. These results, when integrated with existing proteomic and behavioural data, offer new insights into the effects of thermal variations on the nervous system in teleost fish. Specifically, our proteomic and lipidomic findings suggest that elevated temperatures may disrupt mitochondrial function, increase neuronal susceptibility to oxidative stress and cytotoxicity, alter axonal myelination, impair nerve impulse transmission, hinder synapse function and neurotransmitter release, and potentially lead to increased neuronal death. These findings are particularly relevant in the fields of cell biology, neurobiology, and ecotoxicology, especially in the context of global warming. Full article
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Figure 1
<p>Experimental framework for analysing thermal variation effects in adult zebrafish. Fish were maintained at 18 °C (low temperature), 26 °C (control temperature), or 34 °C (high temperature) for 21 days (chronic exposure). After their treatment, the fish were euthanised, and their brains were surgically dissected for lipidomic analysis (red line and arrows). Previous studies conducted by our research group investigated behavioural and brain proteomic responses in zebrafish exposed to the same thermal conditions (black line and arrows). The results indicate that thermal variation significantly alters behaviour, protein expression, and lipid content in the zebrafish brain. <sup>1</sup> and <sup>2</sup> refer to the bibliographic citations of previous works [<a href="#B19-ijms-25-09629" class="html-bibr">19</a>,<a href="#B20-ijms-25-09629" class="html-bibr">20</a>,<a href="#B21-ijms-25-09629" class="html-bibr">21</a>,<a href="#B22-ijms-25-09629" class="html-bibr">22</a>,<a href="#B23-ijms-25-09629" class="html-bibr">23</a>].</p>
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<p>Extraction and analysis of zebrafish brain lipids. Venn diagrams depicting lipids extracted from brains of adult zebrafish subjected for 21 days to three temperature conditions, namely, 18 °C, 26 °C (control), and 34 °C, and analysed via untargeted (<b>A</b>,<b>B</b>) and targeted lipidomics approaches (<b>C</b>,<b>D</b>). A statistical evaluation was applied for each one-to-one comparison. Lipids were considered to be differentially expressed if they were present only in one condition or showed a significant <span class="html-italic">t</span>-test difference (Student’s <span class="html-italic">t</span>-test <span class="html-italic">p</span>-value  ≤  0.05).</p>
Full article ">Figure 3
<p>Untargeted brain lipid profile of adult zebrafish maintained at temperatures of 18 °C (blue), 26 °C (orange), and 34 °C (red). (<b>A</b>): relative amount of the main lipid categories represented with a logarithmic scale. Analysis with two-way ANOVA followed by Tukey’s post hoc test only identified significant differences between phosphatidylcholine and other lipid categories (§, <span class="html-italic">p</span> ≤ 0.05); (<b>B</b>): relative quantity of lipids with different numbers of double covalent bonds in the fatty acid chains. (<b>C</b>): relative quantity of lipids characterised by low (0–6), medium (7–12), and high (13–18) numbers of double covalent bonds. Analysis with two-way ANOVA followed by Tukey’s post hoc test did not identify significant differences in the content of double covalent bonds between temperatures. (<b>D</b>): relative quantity of lipids characterised by different sizes evaluated by the number of carbon atoms in the fatty acid chains. (<b>E</b>): relative quantity of lipids characterised by low (0–25), medium (26–50), and high (51–75) numbers of carbon atoms. Analysis with two-way ANOVA followed by Tukey’s post hoc test did not identify significant differences in the content of double covalent bonds between temperatures. The data are expressed as means ± S.E.M. in all panels. ASG (acylhexose glutathione); CE (cholesterol ester); Cer (ceramides); Cholesterol (cholesterol); DG (diacylglycerol); FA (fatty acid); Hex2Cer (dihexosyl-ceramides); LPC (lysophosphatidylcholine); LPE (lysophosphatidylethanolamine); LPG (lysophosphatidylglycerol); LPI (lysophosphatidylinositol); LPS (lysophosphatidylserine); MG (monoglyceride); MGDG (monogalactosyldiacylglycerol); NAE (N-acylethanolamine); PC (phosphatidylcholine); PE (phosphatidylethanolamine); PG (phosphatidylglycerol); PI (phosphatidylinositol); PS (phosphatidylserine); SHexCer (sulfatides/sulfated hexosyl ceramide); SM (sphingomyelin); SMGDG (sulfomonohexosyldiacylglycerol); TG (triacylglycerol).</p>
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<p>Lipid levels significantly higher at 18 °C compared to 26 °C. Bar graphs show the relative amounts of specific brain lipids at 18 °C (blue) and 26 °C (orange), focusing on those significantly elevated in the 18 °C vs. 26 °C comparison. Lipid species are as follows: (<b>A</b>): PE 36:3;O|PE 16:0_20:3;O (C41H76NO9P); (<b>B</b>): PE 38:3;O|PE 18:0_20:3;O (C43H80NO9P); (<b>C</b>): PE 40:4;O|PE 18:1_22:3;O (C45H82NO9P); (<b>D</b>): PE 42:9;O|PE 22:6_20:3;O (C47H76NO9P); (<b>E</b>): PE 44:9;O|PE 22:6_22:3;O (C49H80NO9P); (<b>F</b>): SM 40:7;O3 (C45H79N2O7P). The data are expressed as means ± S.E.M. and were analysed using one-way ANOVA with Tukey’s post hoc correction. * <span class="html-italic">p</span> ≤ 0.05 in 18 °C versus 26 °C comparison. <span class="html-italic">p</span>-values are reported in <a href="#ijms-25-09629-t001" class="html-table">Table 1</a>. <span class="html-italic">N</span> = 4.</p>
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<p>Lipid levels significantly reduced at 18 °C compared to 26 °C. Bar graphs display the relative amounts of brain lipids at 18 °C (blue) and 26 °C (orange), focusing on those significantly decreased in the 18 °C vs. 26 °C comparison. Lipid species are as follows: (<b>A</b>): SM 37:3;O2 | SM 19:3;O2/18:0 (C42H81N2O6P); (<b>B</b>): SM 38:1;O2 | SM 21:0;O2/17:1 (C43H87N2O6P); (<b>C</b>): SM 40:1;O2 | SM 18:1;O2/22:0 (C45H91N2O6P); (<b>D</b>): SM 40:2;O2 | SM 18:1;O2/22:1 (C45H89N2O6P); (<b>E</b>): SM 42:1;O3 (C47H95N2O7P); (<b>F</b>): SM 42:2;O2 | SM 18:1;O2/24:1 (C47H93N2O6P); (<b>G</b>): SM 42:3;O2 | SM 18:1;O2/24:2 (C47H91N2O6P); (<b>H</b>): SM 42:4;O2 | SM 18:1;O2/24:3 (C47H89N2O6P); (<b>I</b>): SM 44:3;O2 | SM 18:1;O2/26:2 (C49H95N2O6P); (<b>J</b>): SM 44:4;O2 | SM 18:1;O2/26:3 (C49H93N2O6P). The data are expressed as means ± S.E.M. and were analysed via one-way ANOVA with Tukey’s post hoc correction. * <span class="html-italic">p</span> ≤ 0.05 in 18 °C versus 26 °C comparison. <span class="html-italic">p</span>-values are reported in <a href="#ijms-25-09629-t001" class="html-table">Table 1</a>. <span class="html-italic">N</span> = 4.</p>
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<p>Lipids whose levels were significantly increased at 34 compared to 26 °C. Bar graphs display the relative amounts of brain lipids at 26 °C (orange) and 34 °C (red), focusing on those significantly elevated in the 34 °C vs. 26 °C comparison. Lipid species are as follows: (<b>A</b>): PE 34:0;O|PE 16:0_18:0;O (C39H78NO9P); (<b>B</b>): PE 34:1|PE 16:0_18:1 (C39H76NO8P); (<b>C</b>): PE 36:1|PE 18:0_18:1 (C41H80NO8P); (<b>D</b>): PE 38:3;O|PE 18:0_20:3;O (C43H80NO9P); (<b>E</b>): PE 40:1|PE 22:0_18:1 (C45H88NO8P); (<b>F</b>): PE 40:3;O|PE 18:0_22:3;O (C45H84NO9P); (<b>G</b>): PE 42:1|PE 24:0_18:1 (C47H92NO8P); (<b>H</b>): PE 42:2|PE 18:1_24:1 (C47H90NO8P); (<b>I</b>): PE 42:7|PE 18:1_24:6 (C47H80NO8P); (<b>J</b>): PE 44:1|PE 26:0_18:1 (C49H96NO8P); (<b>K</b>): LPE-N (FA)36:0|LPE-N (FA 18:0)18:0 (C41H82NO8P); (<b>L</b>): Cer 50:11;O4|Cer 28:4;O3 (FA 22:6) (C50H79NO5); (<b>M</b>): SM 33:0;O2 (C38H79N2O6P); (<b>N</b>): SM 34:1;O3 (C39H79N2O7P); (<b>O</b>): SM 38:6;O2|SM 17:2;O2/21:4 (C43H77N2O6P); (<b>P</b>): SM 44:0;O2|SM 18:0;O2/26:0 (C49H101N2O6P); (<b>Q</b>): SM 46:6;O3 (C51H93N2O7P). The data are expressed as means ± S.E.M. and were analysed via one-way ANOVA with Tukey’s post hoc correction. <span>$</span> <span class="html-italic">p</span> ≤ 0.05 in 34 °C versus 26 °C comparison. <span class="html-italic">p</span>-values are reported in <a href="#ijms-25-09629-t002" class="html-table">Table 2</a>. <span class="html-italic">N</span> = 4.</p>
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<p>Gangliosides whose levels were significantly increased at 34 °C compared to 26 °C. Bar graphs display the relative amounts of brain gangliosides at 26 °C (orange) and 34 °C (red), focusing on those significantly elevated in the 34 °C vs. 26 °C comparison. Gangliosides species are as follows: (<b>A</b>): GD0a/b(36:0)-2H (C92H161N5O44); (<b>B</b>): GD1a/b (d18:1/18:0) (C85H149N3O39); (<b>C</b>): GD1a/b(36:1) (OH) (C84H148N4O40); (<b>D</b>): GD1a/b(38:1) (NeuGc)-2H/O-Ac-GD1b(36:0)-2H (C86H150N4O40); (<b>E</b>): GM2 d18:1-18:0 (C67H121N3O26); (<b>F</b>): GM3 d18:1-18:0 (C59H108N2O21); (<b>G</b>): GQ1a/b(36:0) (C106H182N6O55); (<b>H</b>): GQ1a/b(36:2) (C106H178N6O55); (<b>I</b>): GT3(36:0) (C81H142N4O37); (<b>J</b>): GT3(42:2) (C87H150N4O37); (<b>K</b>): O-Ac-GD1a/b(38:0)-2H/GD1a/b(40:2) (OH)-2H (C88H154N4O40). The data are expressed as means ± S.E.M. and were analysed via one-way ANOVA with Tukey’s post hoc correction. <span>$</span> <span class="html-italic">p</span> ≤ 0.05 in 34 °C versus 26 °C comparison. <span class="html-italic">p</span>-values are reported in <a href="#ijms-25-09629-t002" class="html-table">Table 2</a>. <span class="html-italic">N</span> = 4.</p>
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<p>Lipids whose levels were significantly reduced at 34 °C compared to 26 °C. Bar graphs display the relative amounts of brain lipids at 26 °C (orange) and 34 °C (red), focusing on those significantly decreased in the 34 °C vs. 26 °C comparison. Lipid species include: (<b>A</b>): LPE O-18:2 (C23H46NO6P); (<b>B</b>): LPE O-18:3 (C23H44NO6P); (<b>C</b>): LPE O-19:1 (C24H50NO6P); (<b>D</b>): LPE O-20:1 (C25H52NO6P); (<b>E</b>): LPE O-20:2 (C25H50NO6P); (<b>F</b>): PE O-42:1|PE O-18:1_24:0 (C47H94NO7P); (<b>G</b>): PE O-44:1|PE O-18:1_26:0 (C49H98NO7P); (<b>H</b>): PG O-38:3|PG O-20:2_18:1 (C44H83O9P); (<b>I</b>): MGDG 34:1|MGDG 16:0_18:1 (C43H80O10). The data are expressed as means ± S.E.M. and were analysed via one-way ANOVA with Tukey’s post hoc correction. <span>$</span> <span class="html-italic">p</span> ≤ 0.05 in <span>$</span> 34 °C versus 26 °C comparison. <span class="html-italic">p</span>-values are reported in <a href="#ijms-25-09629-t002" class="html-table">Table 2</a>. <span class="html-italic">N</span> = 4.</p>
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<p>Schematic representation of the main alterations in the lipid component of the zebrafish brain caused by exposure to low (18 °C vs. 26 °C, above) and high (34 °C vs. 26 °C, below) temperatures and their possible effects. Literature suggests that the observed lipid alterations may impact several cellular and neurological processes, including membrane curvature, vesicular fusion, and budding (<b>A1</b>,<b>A2</b>), mitochondrial function (<b>B</b>), oxidative stress and cytotoxicity (<b>C</b>), neuronal structures such as dendrites, axons, and myelination (<b>D</b>), synaptic activity and neurotransmitter release (<b>E</b>), inflammation (<b>F</b>), and neurodegeneration (<b>G</b>). Downregulation (↓) and upregulation (↑) are indicated. Possible effects, deduced from information from the literature, are indicated in parentheses. Proteome alterations identified in previous work are reported in italics. Previous work are reported in italics: [<a href="#B19-ijms-25-09629" class="html-bibr">19</a>,<a href="#B45-ijms-25-09629" class="html-bibr">45</a>,<a href="#B46-ijms-25-09629" class="html-bibr">46</a>,<a href="#B47-ijms-25-09629" class="html-bibr">47</a>,<a href="#B48-ijms-25-09629" class="html-bibr">48</a>,<a href="#B49-ijms-25-09629" class="html-bibr">49</a>] (<b>A1</b>,<b>A2</b>), [<a href="#B19-ijms-25-09629" class="html-bibr">19</a>,<a href="#B21-ijms-25-09629" class="html-bibr">21</a>,<a href="#B51-ijms-25-09629" class="html-bibr">51</a>,<a href="#B52-ijms-25-09629" class="html-bibr">52</a>,<a href="#B53-ijms-25-09629" class="html-bibr">53</a>,<a href="#B54-ijms-25-09629" class="html-bibr">54</a>,<a href="#B55-ijms-25-09629" class="html-bibr">55</a>] (<b>B</b>), [<a href="#B19-ijms-25-09629" class="html-bibr">19</a>,<a href="#B51-ijms-25-09629" class="html-bibr">51</a>,<a href="#B56-ijms-25-09629" class="html-bibr">56</a>,<a href="#B57-ijms-25-09629" class="html-bibr">57</a>,<a href="#B58-ijms-25-09629" class="html-bibr">58</a>,<a href="#B59-ijms-25-09629" class="html-bibr">59</a>,<a href="#B60-ijms-25-09629" class="html-bibr">60</a>,<a href="#B61-ijms-25-09629" class="html-bibr">61</a>,<a href="#B62-ijms-25-09629" class="html-bibr">62</a>,<a href="#B63-ijms-25-09629" class="html-bibr">63</a>,<a href="#B64-ijms-25-09629" class="html-bibr">64</a>,<a href="#B65-ijms-25-09629" class="html-bibr">65</a>,<a href="#B66-ijms-25-09629" class="html-bibr">66</a>,<a href="#B67-ijms-25-09629" class="html-bibr">67</a>] (<b>C</b>), [<a href="#B19-ijms-25-09629" class="html-bibr">19</a>,<a href="#B21-ijms-25-09629" class="html-bibr">21</a>,<a href="#B68-ijms-25-09629" class="html-bibr">68</a>,<a href="#B69-ijms-25-09629" class="html-bibr">69</a>,<a href="#B70-ijms-25-09629" class="html-bibr">70</a>,<a href="#B71-ijms-25-09629" class="html-bibr">71</a>,<a href="#B72-ijms-25-09629" class="html-bibr">72</a>,<a href="#B73-ijms-25-09629" class="html-bibr">73</a>,<a href="#B74-ijms-25-09629" class="html-bibr">74</a>,<a href="#B75-ijms-25-09629" class="html-bibr">75</a>,<a href="#B76-ijms-25-09629" class="html-bibr">76</a>,<a href="#B77-ijms-25-09629" class="html-bibr">77</a>,<a href="#B78-ijms-25-09629" class="html-bibr">78</a>,<a href="#B79-ijms-25-09629" class="html-bibr">79</a>,<a href="#B80-ijms-25-09629" class="html-bibr">80</a>,<a href="#B81-ijms-25-09629" class="html-bibr">81</a>] (<b>D</b>), [<a href="#B19-ijms-25-09629" class="html-bibr">19</a>,<a href="#B21-ijms-25-09629" class="html-bibr">21</a>,<a href="#B82-ijms-25-09629" class="html-bibr">82</a>,<a href="#B83-ijms-25-09629" class="html-bibr">83</a>,<a href="#B84-ijms-25-09629" class="html-bibr">84</a>] (<b>E</b>), [<a href="#B85-ijms-25-09629" class="html-bibr">85</a>,<a href="#B86-ijms-25-09629" class="html-bibr">86</a>,<a href="#B87-ijms-25-09629" class="html-bibr">87</a>,<a href="#B88-ijms-25-09629" class="html-bibr">88</a>,<a href="#B89-ijms-25-09629" class="html-bibr">89</a>,<a href="#B90-ijms-25-09629" class="html-bibr">90</a>] (<b>F</b>), [<a href="#B21-ijms-25-09629" class="html-bibr">21</a>,<a href="#B51-ijms-25-09629" class="html-bibr">51</a>,<a href="#B55-ijms-25-09629" class="html-bibr">55</a>,<a href="#B63-ijms-25-09629" class="html-bibr">63</a>,<a href="#B64-ijms-25-09629" class="html-bibr">64</a>,<a href="#B71-ijms-25-09629" class="html-bibr">71</a>,<a href="#B72-ijms-25-09629" class="html-bibr">72</a>,<a href="#B76-ijms-25-09629" class="html-bibr">76</a>,<a href="#B88-ijms-25-09629" class="html-bibr">88</a>,<a href="#B91-ijms-25-09629" class="html-bibr">91</a>,<a href="#B92-ijms-25-09629" class="html-bibr">92</a>,<a href="#B93-ijms-25-09629" class="html-bibr">93</a>,<a href="#B94-ijms-25-09629" class="html-bibr">94</a>,<a href="#B95-ijms-25-09629" class="html-bibr">95</a>,<a href="#B96-ijms-25-09629" class="html-bibr">96</a>,<a href="#B97-ijms-25-09629" class="html-bibr">97</a>,<a href="#B98-ijms-25-09629" class="html-bibr">98</a>,<a href="#B99-ijms-25-09629" class="html-bibr">99</a>,<a href="#B100-ijms-25-09629" class="html-bibr">100</a>,<a href="#B101-ijms-25-09629" class="html-bibr">101</a>,<a href="#B102-ijms-25-09629" class="html-bibr">102</a>,<a href="#B103-ijms-25-09629" class="html-bibr">103</a>,<a href="#B104-ijms-25-09629" class="html-bibr">104</a>,<a href="#B105-ijms-25-09629" class="html-bibr">105</a>,<a href="#B106-ijms-25-09629" class="html-bibr">106</a>,<a href="#B107-ijms-25-09629" class="html-bibr">107</a>,<a href="#B108-ijms-25-09629" class="html-bibr">108</a>,<a href="#B109-ijms-25-09629" class="html-bibr">109</a>,<a href="#B110-ijms-25-09629" class="html-bibr">110</a>,<a href="#B111-ijms-25-09629" class="html-bibr">111</a>,<a href="#B112-ijms-25-09629" class="html-bibr">112</a>,<a href="#B113-ijms-25-09629" class="html-bibr">113</a>,<a href="#B114-ijms-25-09629" class="html-bibr">114</a>,<a href="#B115-ijms-25-09629" class="html-bibr">115</a>,<a href="#B116-ijms-25-09629" class="html-bibr">116</a>] (<b>G</b>).</p>
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17 pages, 1310 KiB  
Article
Valorization of Pig Brains for Prime Quality Oil: A Comparative Evaluation of Organic-Solvent-Based and Solvent-Free Extractions
by Jaruwan Chanted, Visaka Anantawat, Chantira Wongnen, Tanong Aewsiri, Worawan Panpipat, Atikorn Panya, Natthaporn Phonsatta, Ling-Zhi Cheong and Manat Chaijan
Foods 2024, 13(17), 2818; https://doi.org/10.3390/foods13172818 - 5 Sep 2024
Viewed by 450
Abstract
Pig processing industries have produced large quantities of by-products, which have either been discarded or used to make low-value products. This study aimed to provide recommendations for manufacturing edible oil from pig brains, thereby increasing the value of pork by-products. The experiment compared [...] Read more.
Pig processing industries have produced large quantities of by-products, which have either been discarded or used to make low-value products. This study aimed to provide recommendations for manufacturing edible oil from pig brains, thereby increasing the value of pork by-products. The experiment compared non-solvent extraction methods, specifically wet rendering and aqueous saline, to a standard solvent extraction method, the Bligh and Dyer method, for extracting oil from pig brains. The yield, color, fatty acid profile, a number of lipid classes, and lipid stability against lipolysis and oxidation of the pig brain oil were comprehensively compared, and the results revealed that these parameters varied depending on the extraction method. The wet rendering process provided the highest extracted oil yield (~13%), followed by the Bligh and Dyer method (~7%) and the aqueous saline method (~2.5%). The Bligh and Dyer method and wet rendering techniques produced a translucent yellow oil; however, an opaque light-brown-red oil was found in the aqueous saline method. The Bligh and Dyer method yielded the oil with the highest phospholipid, cholesterol, carotenoid, tocopherol, and free fatty acid contents (p < 0.05). Although the Bligh and Dyer method recovered the most unsaturated fatty acids, it also recovered more trans-fatty acids. Aqueous saline and wet rendering procedures yielded oil with low FFA levels (<1 g/100 g). The PV of the oil extracted using all methods was <1 meq/kg; however, the Bligh and Dyer method had a significant TBARS content (7.85 mg MDA equivalent/kg) compared to aqueous saline (1.75 mg MDA equivalent/kg) and wet rendering (1.14 mg MDA equivalent/kg) (p < 0.05). FTIR spectra of the pig brain oil revealed the presence of multiple components in varying quantities, as determined by chemical analysis experiments. Given the higher yield and lipid stability and the lower cholesterol and trans-fatty acid content, wet rendering can be regarded as a simple and environmentally friendly method for safely extracting quality edible oil from pig brains, which may play an important role in obtaining financial benefits, nutrition, the zero-waste approach, and increasing the utilization of by-products in the meat industry. Full article
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Figure 1
<p>The appearance of pig brain oil obtained using various extraction methods, namely the Bligh and Dyer method (<b>a</b>), wet rendering (<b>b</b>), and aqueous saline (<b>c</b>).</p>
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<p>Free fatty acid (FFA); (<b>a</b>), peroxide value (PV); (<b>b</b>), and thiobarbituric acid reactive substances (TBARS); (<b>c</b>) of pig brain oil obtained using various extraction methods, namely Bligh and Dyer, wet rendering, and aqueous saline. The bars reflect the standard deviations of triplicate determinations. Different letters denote significant differences (<span class="html-italic">p</span> &lt; 0.05).</p>
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<p>Free fatty acid (FFA); (<b>a</b>), peroxide value (PV); (<b>b</b>), and thiobarbituric acid reactive substances (TBARS); (<b>c</b>) of pig brain oil obtained using various extraction methods, namely Bligh and Dyer, wet rendering, and aqueous saline. The bars reflect the standard deviations of triplicate determinations. Different letters denote significant differences (<span class="html-italic">p</span> &lt; 0.05).</p>
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<p>Fourier transform infrared (FTIR) spectra of pig brain oil obtained using various extraction methods, namely Bligh and Dyer, wet rendering, and aqueous saline.</p>
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16 pages, 5675 KiB  
Article
A Facile and Efficient Protocol for Phospholipid Enrichment in Synovial Joint Fluid: Monodisperse-Mesoporous SiO2 Microspheres as a New Metal Oxide Affinity Sorbent
by Serhat Aladağ, İlayda Demirdiş, Burcu Gökçal Kapucu, Emine Koç, Ozan Kaplan, Batuhan Erhan Aktaş, Mustafa Çelebier, Ali Tuncel and Feza Korkusuz
Separations 2024, 11(9), 262; https://doi.org/10.3390/separations11090262 - 5 Sep 2024
Viewed by 444
Abstract
Phospholipids (PLs), essential components of cell membranes, play significant roles in maintaining the structural integrity and functionality of joint tissues. One of the main components of synovial joint fluid (SJF) is PLs. Structures such as PLs that are found in low amounts in [...] Read more.
Phospholipids (PLs), essential components of cell membranes, play significant roles in maintaining the structural integrity and functionality of joint tissues. One of the main components of synovial joint fluid (SJF) is PLs. Structures such as PLs that are found in low amounts in biological fluids may need to be selectively enriched to be analyzed. Monodisperse-mesoporous SiO2 microspheres were synthesized by a multi-step hydrolysis condensation method for the selective enrichment and separation of PLs in the SJF. The microspheres were characterized by SEM, XPS, XRD, and BET analyses. SiO2 microspheres had a 161.5 m2/g surface area, 1.1 cm3/g pore volume, and 6.7 nm pore diameter, which were efficient in the enrichment of PLs in the SJF. The extracted PLs with sorbents were analyzed using Q-TOF LC/MS in a gradient elution mode with a C18 column [2.1 × 100 mm, 2.5 μM, Xbridge Waters (Milford, MA, USA)]. An untargeted lipidomic approach was performed, and the phospholipid enrichment was successfully carried out using the proposed solid-phase extraction (SPE) protocol. Recovery of the SPE extraction of PLs using sorbents was compared to the classical liquid–liquid extraction (LLE) procedure for lipid extraction. The results showed that monodisperse-mesoporous SiO2 microspheres were eligible for selective enrichment of PLs in SJF samples. These microspheres can be used to identify PLs changes in articular joint cartilage (AJC) in physiological and pathological conditions including osteoarthritis (OA) research. Full article
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Figure 1
<p>Structures of the major phospholipids [<a href="#B24-separations-11-00262" class="html-bibr">24</a>,<a href="#B25-separations-11-00262" class="html-bibr">25</a>].</p>
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<p>Radiographic imaging result and SJF aspiration sample of a 57-year-old patient with grade 4 OA diagnosis.</p>
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<p>Representation of metabolite, protein, and lipid phases from top to bottom, respectively, after the LLE protocol.</p>
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<p>The schematic representation of the synthesis protocol for monodisperse-mesoporous SiO<sub>2</sub> microspheres.</p>
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<p>Different scales SEM photographs of monodisperse-mesoporous SiO<sub>2</sub> microspheres ((<b>a</b>): 20 µm scale, (<b>b</b>): 10 µm scale, (<b>c</b>): 2 µm scale).</p>
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<p>Brunauer–Emmett–Teller (BET) result of monodisperse-mesoporous SiO<sub>2</sub> microspheres.</p>
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<p>XRD spectra of the monodisperse-mesoporous SiO<sub>2</sub> microspheres.</p>
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<p>(<b>A</b>) Survey XPS spectrum, (<b>B</b>) core level spectra for C1s scan, (<b>C</b>) core level spectra for O1s scan, and (<b>D</b>) core level spectra for Si 2p scan with monodisperse-mesoporous SiO<sub>2</sub> microspheres.</p>
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<p>The schematic representation of the phospholipid enrichment using monodisperse-mesoporous SiO<sub>2</sub> microspheres.</p>
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<p>Overlapped based peak chromatograms (<b>A</b>) Base peak chromatograms of the SPE fraction. (<b>B</b>) Base peak chromatograms of the LLE fraction.</p>
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<p>Comparative recovery for PLs using different extraction techniques (SPE: solid-phase extraction, LLE: liquid–liquid extraction).</p>
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<p>The enrichment rates of the sorbent for the phospholipid species predominantly found in SJF (PA: Phosphatidic acid, PC: Phosphatidylcholines, PG: Phosphatidylglycerol, PS: Phosphatidylserine).</p>
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18 pages, 3586 KiB  
Article
A QbD-Navigated Approach to the Development and Evaluation of Etodolac–Phospholipid Complex Containing Polymeric Films for Improved Anti-Inflammatory Effect
by Jangjeet Karan Singh, Simran Kaur, Balakumar Chandrasekaran, Gurpreet Kaur, Balraj Saini, Rajwinder Kaur, Pragati Silakari, Narinderpal Kaur and Pallavi Bassi
Polymers 2024, 16(17), 2517; https://doi.org/10.3390/polym16172517 - 4 Sep 2024
Viewed by 403
Abstract
The current study focuses on development of phospholipid complex-loaded films of etodolac for enhanced transdermal permeation and anti-inflammatory effect. An etodolac–phospholipid complex was developed using the solvent evaporation method and was characterized by DSC, XRD, FTIR, and 1H-NMR studies. The formation of [...] Read more.
The current study focuses on development of phospholipid complex-loaded films of etodolac for enhanced transdermal permeation and anti-inflammatory effect. An etodolac–phospholipid complex was developed using the solvent evaporation method and was characterized by DSC, XRD, FTIR, and 1H-NMR studies. The formation of the complex led to conversion of a crystalline drug to an amorphous form. A stoichiometric ratio of 1:1 (drug–phospholipid) was selected as the optimized ratio. Further, the developed complex was incorporated into films and systematic optimization using a central composite design was carried out using a response surface methodological approach. The desirable design space based on minimum contact angle and maximum tensile strength was selected, while the water vapour transmission rate and swelling index were set within limits. The results for swelling index, contact angle, tensile strength, and water vapour transmission rate were 60.14 ± 1.01%, 31.6 ± 0.03, 2.44 ± 0.39 kg/cm2, and 15.38 g/hm2, respectively. These values exhibited a good correlation with the model-predicted values. The optimized formulation exhibited improved diffusion and permeation across skin. In vivo studies revealed enhanced anti-inflammatory potential of the developed films in comparison to the un-complexed drug. Hence, the study demonstrated that etodolac–phospholipid complex-loaded films improve the transdermal permeation and provided enhanced anti-inflammatory effect. Full article
(This article belongs to the Special Issue Polymeric Materials for Drug Delivery Applications)
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<p>Three-dimensional interactions of ETO with phosphatidylcholine transfer protein: The hydrogen bonds are indicated with blue dashed lines, and the aromatic interactions are in purple dashed lines.</p>
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<p>(<b>I</b>) Job plot depicting absorbance difference with respect to mole fraction of ETO. (<b>II</b>) Solubility of ETO and the ETO–PLO complex in different solvents. Solubilities are represented as mean ± SD (<span class="html-italic">n</span> = 3). ** <span class="html-italic">p</span> &lt; 0.05 as compared to ETO at the same pH value.</p>
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<p>(<b>I</b>) FTIR spectra of ETO (<b>a</b>), PL (<b>b</b>), ETO–PLC 4:6 ratio (<b>c</b>), ETO–PLC 1:1 Ratio (<b>d</b>).; (<b>II</b>) XRD diffractograms of ETO (<b>a</b>), ETO–PLC 4:6 ratio (<b>b</b>) and ETO–PLC 1:1 ratio (<b>c</b>); (<b>III</b>) DSC thermograph of ETO (<b>a</b>) and ETO -PLC (1:1) (<b>b</b>)</p>
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<p>(I) SEM images at different magnifications of ETO (<b>a</b>,<b>b</b>), ETO–PLC 4:6 ratio (<b>c</b>,<b>d</b>) and ETO–PLC 1:1 ratio (<b>e</b>,<b>f</b>).</p>
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<p><sup>1</sup>H NMR spectra of ETO (<b>a</b>), ETO–PLC 1:1 (<b>b</b>).</p>
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<p>(<b>I</b>) Ishikawa fishbone diagram depicting factors affecting the critical quality attributes of films; (<b>II</b>) Risk assessment matrix (Red: high risk, yellow: medium risk and green: low risk) for the different CMAs and CPPs affecting the CQAs</p>
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<p>Pareto plots of contact angle (<b>a</b>), swelling index (<b>b</b>), water vapour transmission rate (<b>c</b>), and tensile strength (<b>d</b>).</p>
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<p>(<b>I</b>) Response surface plots for CA (<b>a</b>), swelling index (<b>b</b>), tensile strength (<b>c</b>), and water vapour transmission rate (<b>d</b>); (<b>II</b>) Desirability plot and the optimized design space (white indicates the desirability region, other colors indicate the region for other CQAs).</p>
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<p>(<b>I</b>) In vitro drug diffusion profile of of ETO–PLC and ETO–PLC loaded films; (<b>II</b>) ETO–PLC loaded films release data fitting into the Korsmeyer–Peppas equation.</p>
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15 pages, 4272 KiB  
Article
Water Management-Mediated Changes in the Rhizosphere and Bulk Soil Microbial Communities Alter Their Utilization of Urea-Derived Carbon
by Peng Chen, Yawei Li, Yuping Lv, Junzeng Xu, Zhongxue Zhang, Xiaoyin Liu, Yajun Luan, Qi Wei, Ennan Zheng and Kechun Wang
Microorganisms 2024, 12(9), 1829; https://doi.org/10.3390/microorganisms12091829 - 4 Sep 2024
Viewed by 406
Abstract
As one of the most important fertilizers in agriculture, the fate of urea-derived nitrogen (urea-N) in agricultural ecosystems has been well documented. However, little is known about the function of urea-derived carbon (urea-C) in soil ecosystems, especially which soil microorganisms benefit most from [...] Read more.
As one of the most important fertilizers in agriculture, the fate of urea-derived nitrogen (urea-N) in agricultural ecosystems has been well documented. However, little is known about the function of urea-derived carbon (urea-C) in soil ecosystems, especially which soil microorganisms benefit most from the supply of urea-C and whether the utilization of urea-C by the rhizosphere and bulk soil microorganisms is affected by irrigation regimes. To address this, a soil pot experiment was conducted using 13C-labeled urea to investigate changes in the composition of the rhizosphere and bulk soil microbial communities and differences in the incorporation of urea-derived C into the rhizosphere and bulk soil phospholipid fatty acids (PLFA) pool under flooded irrigation (FI) and water-saving irrigation (CI). Our results suggest that the size and structure of the rhizosphere and bulk soil microbial communities were strongly influenced by the irrigation regime. The CI treatment significantly increased the total amount of PLFA in both the rhizosphere and bulk soil compared to the FI treatment, but it only significantly affected the abundance of Gram-positive bacteria (G+) in the bulk soil. In contrast, shifts in the microbial community structure induced by irrigation regimes were more pronounced in the rhizosphere soil than in the bulk soil. Compared to the FI treatment, the CI treatment significantly increased the relative abundances of the G+ and Actinobacteria in the rhizosphere soil (p < 0.05). According to the PLFA-SIP, most of the labeled urea-derived C was incorporated into 16:1ω7c, 16:0 and 18:1ω7c under both treatments. Despite these general trends, the pattern of 13C incorporation into the PLFA pool differed between the treatments. The factor loadings of individual PLFAs suggested that 18:1ω7c, 16:1ω7c and 16:1ω5c were relatively enriched in urea-C in the bulk soil, while 17:1ω8c, i16:0 and 16:0 were relatively enriched in urea-C in the rhizosphere soil under different irrigation regimes. The loadings also confirmed that 10-me16:0, cy17:0 and cy19:0 were relatively enriched in urea-C under the CI treatment, whereas 14:0, a15:0 and 15:0 were relatively enriched in urea-C under the FI treatment. These results are helpful not only in revealing the interception mechanism of urea-C in soil but also in understanding the functions of key microbes in element cycles. Full article
(This article belongs to the Section Environmental Microbiology)
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<p>Schematic diagram of soil culture experiment.</p>
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<p>Retention of urea-<sup>13</sup>C in rhizosphere soil (<b>A</b>), bulk soil (<b>B</b>) and rhizosphere + bulk soil (<b>C</b>).</p>
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<p>Total amounts of PLFAs on the 7th and 21st days. Different letters above the bars indicate significant differences at <span class="html-italic">p</span> &lt; 0.05 between CI and FI treatment.</p>
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<p>Composition (<b>A</b>,<b>B</b>) and content (<b>C</b>,<b>D</b>) of PLFAs under different treatments. Different letters above the bars indicate significant differences at <span class="html-italic">p</span> &lt; 0.05 between CI and FI treatment.</p>
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<p>(<b>A</b>) Principal component analysis (PCA) based on the relative abundance of individual PLFA in soil samples at seventh day and (<b>B</b>) a loading plot of two components from the PCA on the PLFA component. Values in parentheses on the axis labels indicates the percentage variation accounted for by each axis.</p>
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<p>Total <sup>13</sup>C-labeled PLFA content and the relative abundance <sup>13</sup>C-labeled PLFAs in the different microbial groups in soil sampled 7 days after urea application.</p>
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<p>Relative abundance of individual <sup>13</sup>C-PLFA from urea-derived <sup>13</sup>C in soil sampled 7 days after urea application.</p>
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<p>Relative abundance of individual <sup>13</sup>C-PLFA from urea-derived <sup>13</sup>C in soil sampled 7 days after urea application.</p>
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<p>(<b>A</b>) Principal component analysis (PCA) of <sup>13</sup>C-PLFA composition in soil samples on the seventh day and (<b>B</b>) a loading plot of the two the PCA on the PLFA components. Values in parentheses on the axis labels indicate the percentage variation accounted for by each axis.</p>
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<p>Urea-C uptake by rice. Different letters above the bars indicate significant differences at <span class="html-italic">p</span> &lt; 0.05 between CI and FI treatment.</p>
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11 pages, 2095 KiB  
Article
ALCAT1-Mediated Pathological Cardiolipin Remodeling and PLSCR3-Mediated Cardiolipin Transferring Contribute to LPS-Induced Myocardial Injury
by Dong Han, Chenyang Wang, Xiaojing Feng, Li Hu, Beibei Wang, Xinyue Hu and Jing Wu
Biomedicines 2024, 12(9), 2013; https://doi.org/10.3390/biomedicines12092013 - 3 Sep 2024
Viewed by 392
Abstract
Cardiolipin (CL), a critical phospholipid situated within the mitochondrial membrane, plays a significant role in modulating intramitochondrial processes, especially in the context of certain cardiac pathologies; however, the exact effects of alterations in cardiolipin on septic cardiomyopathy (SCM) are still debated and the [...] Read more.
Cardiolipin (CL), a critical phospholipid situated within the mitochondrial membrane, plays a significant role in modulating intramitochondrial processes, especially in the context of certain cardiac pathologies; however, the exact effects of alterations in cardiolipin on septic cardiomyopathy (SCM) are still debated and the underlying mechanisms remain incompletely understood. This study highlights a notable increase in the expressions of ALCAT1 and PLSCR3 during the advanced stage of lipopolysaccharide (LPS)-induced SCM. This up-regulation potential contribution to mitochondrial dysfunction and cellular apoptosis—as indicated by the augmented oxidative stress and cytochrome c (Cytc) release—coupled with reduced mitophagy, decreased levels of the antiapoptotic protein B-cell lymphoma-2 (Bcl-2) and lowered cell viability. Additionally, the timing of LPS-induced apoptosis coincides with the decline in both autophagy and mitophagy at the late stages, implying that these processes may serve as protective factors against LPS-induced SCM in HL-1 cells. Together, these findings reveal the mechanism of LPS-induced CL changes in the center of SCM, with a particular emphasis on the importance of pathological remodeling and translocation of CL to mitochondrial function and apoptosis. Additionally, it highlights the protective effect of mitophagy in the early stage of SCM. This study complements previous research on the mechanism of CL changes in mediating SCM. These findings enhance our understanding of the role of CL in cardiac pathology and provide a new direction for future research. Full article
(This article belongs to the Special Issue Sepsis: Pathophysiology and Early Diagnostics)
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<p>Changes in cell death and oxidative stress in the LPS-induced HL-1 cardiac cells: (<b>a</b>) cell viability was scored by methyl thiazolyl tetrazolium (MTT) assay, <span class="html-italic">n</span> = 5 independent experiments; (<b>b</b>) the level of SOD activity decreased in LPS-induced HL-1 cells, <span class="html-italic">n</span> = 3 independent experiments; (<b>c</b>) the level of MDA activity increased in LPS-induced HL-1 cells, <span class="html-italic">n</span> = 3 independent experiments. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, compared with the control group.</p>
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<p>Changes in autophagy and apoptosis in the LPS-induced HL-1 cardiac cells: (<b>a</b>) Western blot images showing the time-course change in LC3-II in LPS-induced HL-1 cells, <span class="html-italic">n</span> = 5 independent experiments; (<b>b</b>) Western blot images showing the time-course change in P62 in LPS-induced HL-1 cells, <span class="html-italic">n</span> = 4 independent experiments; (<b>c</b>) Western blot images showing the change in BCL2 in LPS-induced HL-1 cells, <span class="html-italic">n</span> = 4 independent experiments; (<b>d</b>) Western blot images showing the change in cytochrome c in LPS-induced HL-1 cells, <span class="html-italic">n</span> = 3 independent experiments; (<b>e</b>) LC3 aggregation quantified under confocal fluorescence microscopy. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, compared with the control group.</p>
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<p>Changes in mitophagy in the LPS-induced HL-1 cardiac cells. Representative TEM images of HL-1 cells in control, LPS-treated for 4 h, LPS-treated for 24 h. The images below showcase an enlarged view delineated by the dashed boundary. Arrows, formation of autophagosomes.</p>
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<p>Changes in ALCAT1 protein and PLSCR3 protein in LPS-induced HL-1 cells: (<b>a</b>) Western blot images showing the time-course change in ALCAT1 in LPS-induced HL-1 cells, <span class="html-italic">n</span> = 4 independent experiments; (<b>b</b>) Western blot images showing the time-course change in PLSCR3 in LPS-induced HL-1 cells, <span class="html-italic">n</span> = 4 independent experiments. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, compared with the control group.</p>
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15 pages, 1682 KiB  
Article
Two-Step Macromolecule Separation Process with Acid Pretreatment and High-Shear-Assisted Extraction for Microalgae-Based Biorefinery
by Donghyun Kim, Seul-Gi Kang, Yong Keun Chang and Minsoo Kwak
Sustainability 2024, 16(17), 7589; https://doi.org/10.3390/su16177589 - 2 Sep 2024
Viewed by 680
Abstract
A simple two-stage extraction and recovery method for macromolecules from microalgae biomass, termed CASS (concentrating the microalgae solution, acid pretreatment, high-shear-assisted lipid extraction, and separation), was developed. This method effectively processed the wet biomass of Chlorella sp. ABC-001 at a moderately low biomass [...] Read more.
A simple two-stage extraction and recovery method for macromolecules from microalgae biomass, termed CASS (concentrating the microalgae solution, acid pretreatment, high-shear-assisted lipid extraction, and separation), was developed. This method effectively processed the wet biomass of Chlorella sp. ABC-001 at a moderately low biomass concentration (50 g/L). The optimal conditions were acid pretreatment with 5 wt.% H2SO4 at 100 °C for 1 h, followed by high-shear extraction using hexane at 3000 rpm for 30 min. The acid pretreatment hydrolyzed carbohydrates and phospholipids, disrupting the cell wall and membrane, while high-shear mixing enhanced mass transfer rates between solvents and lipids, overcoming the hydraulic barrier at the cell surface. Within 10 min after completing the process, the extraction mixture achieved natural phase separation into water, solvent, and biomass residue layers, each enriched with carbohydrates, lipids, and proteins, respectively. The CASS process demonstrated high esterifiable lipid yields (91%), along with substantial recovery of glucose (90%) and proteins (100%). The stable phase separation prevented emulsion formation, simplifying downstream processing. This study presents the results on cell disruption, optimal acid treatment concentration, and high-shear mixing to achieve macromolecule separation, expanding the lipid-centric microalgal process to a comprehensive biorefinery concept. Full article
(This article belongs to the Topic Biomass Transformation: Sustainable Development)
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<p>Microalgal-based biorefinery based on the CASS process.</p>
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<p>(<b>a</b>) Effect of acid concentration, (<b>b</b>) acid treatment time, and (<b>c</b>) acid treatment temperature on lipid extraction recovered by using a conventional stirrer at 1000 rpm for 12 h.</p>
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<p>Microscopic image of <span class="html-italic">Chlorella</span> sp. ABC-001 before (control) and after acid treatment at various temperature conditions (5 wt.%, 1 h treatment). The scale bar is 10 μm. Morphological changes are highlighted in red circles. (a) A normal cell; (b) the overall size of the cell is enlarged, and its shape starts to deviate from a sphere; (c) disrupted cells are agglomerated with cell debris; and (d) a complete cell rupture is observed.</p>
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<p>Effect of rotational speed and mixing time on the esterifiable lipid recovery yield using (<b>a</b>) a conventional stirrer and (<b>b</b>) a high-shear mixer after acid treatment (5 wt.%, 100 °C, 1 h).</p>
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<p>The composition and proposed use of three layers resulting from the natural separation of the extraction mixture obtained from the complete CASS process.</p>
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15 pages, 2485 KiB  
Article
Maternal Docosahexaenoic Acid Supplementation Alters Maternal and Fetal Docosahexaenoic Acid Status and Placenta Phospholipids in Pregnancies Complicated by High Body Mass Index
by Katie L. Bidne, Karin Zemski Berry, Mairead Dillon, Thomas Jansson and Theresa L. Powell
Nutrients 2024, 16(17), 2934; https://doi.org/10.3390/nu16172934 - 2 Sep 2024
Viewed by 697
Abstract
Introduction: An optimal fetal supply of docosahexaenoic acid (DHA) is critical for normal brain development. The relationship between maternal DHA intake and DHA delivery to the fetus is complex and is dependent on placental handling of DHA. Little data exist on placental DHA [...] Read more.
Introduction: An optimal fetal supply of docosahexaenoic acid (DHA) is critical for normal brain development. The relationship between maternal DHA intake and DHA delivery to the fetus is complex and is dependent on placental handling of DHA. Little data exist on placental DHA levels in pregnancies supplemented with the recommended dose of 200 mg/d. Our objective was to determine how prenatal DHA at the recommended 200 mg/d impacts maternal, placental, and fetal DHA status in both normal-weight and high-BMI women compared to women taking no supplements. Methods: Maternal blood, placenta, and cord blood were collected from 30 healthy pregnant women (BMI 18.9–43.26 kg/m2) giving birth at term. Red blood cells (RBCs) and villous tissue were isolated, and lipids were extracted to determine DHA content by LC-MS/MS. Data were analyzed by supplement group (0 vs. 200 mg/d) and maternal BMI (normal weight or high BMI) using two-way ANOVA. We measured maternal choline levels in maternal and cord plasma samples. Results: Supplementation with 200 mg/d DHA significantly increased (p < 0.05) maternal and cord RBC DHA content only in pregnancies complicated by high BMI. We did not find any impact of choline levels on maternal or cord RBC phospholipids. There were no significant differences in total placental DHA content by supplementation or maternal BMI (p > 0.05). Placental levels of phosphatidylinositol (PI) and phosphatidic acid containing DHA species were higher (p < 0.05) in high-BMI women without DHA supplementation compared to both normal-BMI and high-BMI women taking DHA supplements. Conclusion: Maternal DHA supplementation at recommended doses cord increased RBC DHA content only in pregnancies complicated by higher BMI. Surprisingly, we found that obesity was related to an increase in placental PI and phosphatidic acid species, which was ameliorated by DHA supplementation. Phosphatidic acid activates placental mTOR, which regulates amino acid transport and may explain previous findings of the impact of DHA on placental function. Current recommendations for DHA supplementation may not be achieving the goal of improving fetal DHA levels in normal-weight women. Full article
(This article belongs to the Special Issue Nutrition and Supplements during Pregnancy (2nd Edition))
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<p>(<b>A</b>) Maternal RBC, (<b>B</b>) Cord RBC, and (<b>C</b>) Placental DHA status. Different letters indicate statistical differences between groups via two-way ANOVA with multiple comparisons and Tukey’s modification, <span class="html-italic">p</span> &lt; 0.05.</p>
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<p>Placenta DHA-containing (<b>A</b>) phosphatidylethanolamines and phosphatidylcholines, (<b>B</b>) phosphatidylinositols, and (<b>C</b>) phosphatidic acids. Different letters indicate statistical differences between groups via two-way ANOVA with multiple comparisons and Tukey’s modification, <span class="html-italic">p</span> &lt; 0.05.</p>
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<p>Selected placenta: (<b>A</b>) phosphatidylcholines and (<b>B</b>) phosphatidylethanolamines. Different letters indicate statistical differences between groups via two-way ANOVA with multiple comparisons and Tukey’s modification, <span class="html-italic">p</span> &lt; 0.05.</p>
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<p>Selected placenta: (<b>A</b>,<b>B</b>) phosphatidylinositols and (<b>C</b>) phosphatidic acids. Different letters indicate statistical differences between groups via two-way ANOVA with multiple comparisons and Tukey’s modification, <span class="html-italic">p</span> &lt; 0.05.</p>
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<p><b>(A)</b> Maternal and (<b>B</b>) cord plasma choline concentrations. No differences between any groups via two-way ANOVA with Tukey’s adjustment.</p>
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<p>Correlations of (<b>A</b>) maternal and cord plasma choline, (<b>B</b>) Maternal RBC DHA and maternal plasma choline, and (<b>C</b>) Cord RBC DHA and cord plasma choline. Data were analyzed using Pearson’s correlation.</p>
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<p>Phosphatidylinositol pathway showing PI is sequentially metabolized into phosphoinositol-4-phosphate (PI4P) and phosphatidylinositol 4,5-bisphosphate (PIP2). PIP2 can be converted by phospholipase C (PLC) into diacylglycerol (DAG), which is acted upon by diacyglycerol kinase (DGK) to form phosphatidic acid (PA), which can be used for the generation of PI, PC, and PE phospholipids.</p>
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22 pages, 6668 KiB  
Article
Multi-Omics Reveals the Role of Arachidonic Acid Metabolism in the Gut–Follicle Axis for the Antral Follicular Development of Holstein Cows
by Yajun Guo, Shiwei Wang, Xuan Wu, Rong Zhao, Siyu Chang, Chen Ma, Shuang Song and Shenming Zeng
Int. J. Mol. Sci. 2024, 25(17), 9521; https://doi.org/10.3390/ijms25179521 - 1 Sep 2024
Viewed by 560
Abstract
In vitro embryonic technology is crucial for improving farm animal reproduction but is hampered by the poor quality of oocytes and insufficient development potential. This study investigated the relationships among changes in the gut microbiota and metabolism, serum features, and the follicular fluid [...] Read more.
In vitro embryonic technology is crucial for improving farm animal reproduction but is hampered by the poor quality of oocytes and insufficient development potential. This study investigated the relationships among changes in the gut microbiota and metabolism, serum features, and the follicular fluid metabolome atlas. Correlation network maps were constructed to reveal how the metabolites affect follicular development by regulating gene expression in granulosa cells. The superovulation synchronization results showed that the number of follicle diameters from 4 to 8 mm, qualified oocyte number, cleavage, and blastocyst rates were improved in the dairy heifers (DH) compared with the non-lactating multiparous dairy cows (NDC) groups. The gut microbiota was decreased in Rikenellaceae_RC9_gut_group, Alistipes, and Bifidobacterium, but increased in Firmicutes, Cyanobacteria, Fibrobacterota, Desulfobacterota, and Verrucomicrobiota in the NDC group, which was highly associated with phospholipid-related metabolites of gut microbiota and serum. Metabolomic profiling of the gut microbiota, serum, and follicular fluid further demonstrated that the co-metabolites were phosphocholine and linoleic acid. Moreover, the expression of genes related to arachidonic acid metabolism in granulosa cells was significantly correlated with phosphocholine and linoleic acid. The results in granulosa cells showed that the levels of PLCB1 and COX2, participating in arachidonic acid metabolism, were increased in the DH group, which improved the concentrations of PGD2 and PGF in the follicular fluid. Finally, the expression levels of apoptosis-related proteins, cytokines, and steroidogenesis-related genes in granulosa cells and the concentrations of steroid hormones in follicular fluid were determinants of follicular development. According to our results, gut microbiota-related phosphocholine and linoleic acid participate in arachidonic acid metabolism in granulosa cells through the gut–follicle axis, which regulates follicular development. These findings hold promise for enhancing follicular development and optimizing oocyte quality in subfertile dairy cows. Full article
(This article belongs to the Section Molecular Endocrinology and Metabolism)
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<p>Serum concentrations of key biochemicals and reproductive hormones and antral follicle numbers at OPU in the DH and NDC groups. (<b>A</b>) Serum levels of alanine transaminase (ALT) and aspartate aminotransferase (AST) on D0 of OPU in the DH and NDC groups (<span class="html-italic">n</span> = 3 per group). (<b>B</b>) Serum cortisol (COR) levels on D0 of OPU in the DH and NDC groups (<span class="html-italic">n</span> = 3 per group). (<b>C</b>) Serum levels of triglycerides (TG), glucose (GLU), cholesterol (CHOL), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) on D0 of OPU in the DH and NDC groups (<span class="html-italic">n</span> = 3 per group). (<b>D</b>) Serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estrogen (E<sub>2</sub>), and progesterone (P<sub>4</sub>) on D0 of OPU in the DH and NDC groups (<span class="html-italic">n</span> = 3 per group). (<b>E</b>) Serum levels of FSH, LH, E<sub>2,</sub> and P<sub>4</sub> on D5 of OPU in the DH and NDC groups (<span class="html-italic">n</span> = 3 per group). (<b>F</b>) Ultrasound images of follicular development on D5 of OPU in the DH and NDC groups. The white dashed box indicates the ovary and the red pentagonal star indicates the follicle. Bar scale 8 mm. Data are presented as mean ± SD. Student’s <span class="html-italic">t</span>-test (two-tailed) was used for statistical analysis. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01. ns: not significant. DH: dairy heifers, NDC: non-lactating multiparous dairy cows.</p>
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<p>Composition of the gut microbiota in the DH and NDC groups. (<b>A</b>) Taxonomic annotation of gut microbiota for DH and NDC samples. (<b>B</b>) Relative abundance of gut microbiota at the phylum level in the DH and NDC samples. (<b>C</b>) Relative abundance of gut microbiota at the genus level in the DH and NDC samples. (<b>D</b>) Alpha diversity evaluation of gut microbiota richness and evenness by measuring Chao and Shannon diversity indexes. <span class="html-italic">p</span> &lt; 0.05 significant difference, <span class="html-italic">p</span> &lt; 0.01 highly significant difference, <span class="html-italic">p</span> ≥ 0.05 insignificant difference. (<b>E</b>) Rarefaction curves of gut microbiota for DH and NDC groups. (<b>F</b>) Bray-Curtis Principal coordinate analysis plot of gut microbiota based on the operational taxonomic unit metrics of the samples in the DH and NDC groups. (<b>G</b>) Unweighted pair-group method with arithmetic mean (UPGMA) analysis at the phylum level for DH and NDC samples. (<b>H</b>) UPGMA analysis at the genus level for DH and NDC samples. <span class="html-italic">n</span> = 8 per group.</p>
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<p>Identification of key differential gut microbiota in the DH and NDC groups. (<b>A</b>) Principal coordinates analysis (PCoA) for the DH and NDC groups. (<b>B</b>,<b>C</b>) Linear discriminant analysis effect size (LEfSe) was performed to identify the differential microbiota in the DH and NDC groups. (<b>D</b>) Heatmap showing the differences in gut microbiota abundance at the phylum level between the DH and NDC groups. (<b>E</b>) The random forest analysis demonstrated the importance ranking of differential gut microbes at the phylum level between the DH and NDC groups. (<b>F</b>) Heatmap showing the difference in gut microbiota abundance at the genus level between the DH and NDC groups. (<b>G</b>) The random forest analysis demonstrated the importance ranking of differential gut microbes at the genus level in the two groups. <span class="html-italic">n</span> = 8 per group.</p>
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<p>The composition and different metabolites of gut microbiota and correlation with gut microbiota between the DH and NDC groups. (<b>A</b>,<b>B</b>) Heatmap showing the relative abundance of key identified metabolites (VIP &gt; 1, <span class="html-italic">p</span> &lt; 0.05). (<b>C</b>) KEGG enrichment analysis of differential metabolites. (<b>D</b>) Relative levels of differential metabolites of ABC transporters. (<b>E</b>) Relative levels of the differential metabolites of steroid hormone biosynthesis. (<b>F</b>) Spearman’s correlation analysis of different gut microbiota and metabolites. Blue indicates a positive correlation and red indicates a negative correlation. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01.</p>
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<p>Composition and differences in serum metabolites between the DH and NDC groups. (<b>A</b>,<b>B</b>) Heatmap showing the relative abundance of the key identified metabolites (VIP &gt;1, <span class="html-italic">p</span> &lt; 0.05. <span class="html-italic">n</span> = 6 per group). (<b>C</b>) KEGG enrichment analysis of differential metabolites. (<b>D</b>) Correlation analysis of gut microbiota and serum metabolites. Blue indicates a positive correlation and red indicates a negative correlation. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01. <span class="html-italic">n</span> = 6 per group.</p>
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<p>Composition and different metabolites in the follicular fluid between the DH and NDC groups. (<b>A</b>,<b>B</b>) Heatmap showing the relative abundance of the key identified metabolites (VIP &gt; 1, <span class="html-italic">p</span> &lt; 0.05). (<b>C</b>) KEGG enrichment analysis of different metabolites. (<b>D</b>) Relative levels of different metabolites of protein digestion and absorption. (<b>E</b>) Relative levels of different metabolites of ABC transporters. (<b>F</b>) Relative levels of the differential metabolites of cholesterol metabolism. (<b>G</b>) Relative levels of different biosynthesis of amino acids metabolites. <span class="html-italic">n</span> = 6 per group.</p>
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<p>The different expression of genes in granulosa cells between the DH and NDC groups. (<b>A</b>) PCA analysis. (<b>B</b>) Volcano plot showing the changes in gene expression. (<b>C</b>) Heatmap of differentially expressed genes (DEGs). (<b>D</b>) GO enrichment analysis of DEGs. (<b>E</b>) KEGG pathway enrichment analysis of up-regulation DEGs. (<b>F</b>) KEGG pathway enrichment analysis of down-regulation DEGs. (<b>G</b>) Heatmap illustrating the expression of genes related to apoptosis and programmed cell death in the two groups. (<b>H</b>) Heatmap illustrating the expression of genes related to arachidonic acid metabolism in DH and NDC groups. (<b>I</b>) The heatmap illustrates the expression of genes related to steroid hormone metabolism in the two groups. (<b>J</b>) Heatmap illustrating the expression of genes related to growth factors in the two groups. <span class="html-italic">n</span> = 4 per group.</p>
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<p>Screening for shared metabolites among gut microbiota, serum, and follicular fluid to construct their regulatory network in granulosa cells. (<b>A</b>–<b>C</b>) The important metabolites in gut microbiome (<b>A</b>), serum (<b>B</b>), and follicular fluid (<b>C</b>) by the random forest analysis. (<b>D</b>–<b>F</b>) Expression of metabolites related to membrane phospholipids in rectal feces (<b>D</b>), serum (<b>E</b>), and follicular fluid (<b>F</b>). (<b>G</b>) The network maps in linoleic acid and arachidonic acid metabolism pathways. The red line showed a positive correlation and the green line indicates a negative correlation (|R| &gt; 0.8 and <span class="html-italic">p</span> &lt; 0.01). * <span class="html-italic">p</span> &lt; 0.05.</p>
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<p>Metabolite levels in follicular fluid related to arachidonic acid and steroid hormones, and gene expression in granulosa cells related to both pathways. (<b>A</b>) Levels of arachidonic acid metabolites in follicular fluid (<span class="html-italic">n</span> = 3 per group). (<b>B</b>,<b>C</b>) The levels of PTGS2, ALOX5, and PLCB1 in granulosa cells. (<b>D</b>) The mRNA expression levels of genes related to apoptosis, arachidonic acid metabolism, steroid hormones synthesis, and inflammation in granulosa cells. (<b>E</b>,<b>F</b>) The levels of steroid hormones metabolites in follicular fluid (<span class="html-italic">n</span> = 3 per group). (<b>G</b>) Correlation between metabolites in the arachidonic acid metabolism and steroid hormones synthesis. (<b>H</b>,<b>I</b>) The levels of HIF-1α, SOD1, ERK1/2, P-ERK1/2, and p38MAPK in granulosa cells. (<b>J</b>,<b>K</b>) The levels of apoptosis-related proteins (BCL2, BAX, CASP3, and P53), and programmed cell death-related proteins in granulosa cells (IRF1, RIPK1, GSDMD, IL-1B, and MIF). (<b>L</b>) Comparison of COX2, PLCB1, and ALOX5 expression between healthy (HF) and atresia (AF) follicles by immunofluorescence staining. COX2, PLCB1, and ALOX5 were stained green. DNA was stained blue. White dashed line indicates follicular basement membrane. Scale bar, 20μm. Data are presented as mean ± SD. Student’s <span class="html-italic">t</span>-test (two-tailed) was used for statistical analysis. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, ns: not significant.</p>
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14 pages, 6012 KiB  
Article
Quantitative and Qualitative Relationships between Phospholipid Fatty Acid Analysis Biomarkers and Lignin in Soil from the Tibetan Plateau (China) under Laboratory Incubation Conditions
by Degyi Yangzom, Shuqin Ma and Xuyang Lu
Agronomy 2024, 14(9), 1980; https://doi.org/10.3390/agronomy14091980 - 1 Sep 2024
Viewed by 319
Abstract
Lignin, an organic compound with a complex structure, is formed through the polymerization of structural units linked by carbon–carbon bonds and ether bonds. The question of whether lignin is labile or resistant to biological and chemical degradation in soil, particularly in alpine ecosystems, [...] Read more.
Lignin, an organic compound with a complex structure, is formed through the polymerization of structural units linked by carbon–carbon bonds and ether bonds. The question of whether lignin is labile or resistant to biological and chemical degradation in soil, particularly in alpine ecosystems, remains unresolved. To address this knowledge gap, we analyzed the relationship between phospholipid fatty acid biomarkers and the abundance of lignin components in grassland soils from North Tibet, China. Soil samples were collected from alpine grasslands, including alpine meadows and alpine steppes. The relative abundance of lignin in these alpine grassland soils before and after a 210-day incubation period was measured. Our results indicate that the relative abundance of lignin in the alpine grassland soils decreased during the incubation period. Significant relationships were found between the phospholipid fatty acid biomarkers of bacteria, fungi, Gram-positive bacteria, and Gram-negative bacteria and the relative abundance of lignin components. This research was conducted under laboratory conditions that are optimal for the development of microorganisms but significantly different from the conditions in Tibet. Furthermore, this study contributes to the understanding of soil organic matter degradation and the dynamics of microbial communities in alpine grassland soils in the context of future global warming. Full article
(This article belongs to the Special Issue Multifunctionality of Grassland Soils: Opportunities and Challenges)
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<p>Photographs of the studied areas.</p>
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<p>The dominant compositions of lignin in alpine grassland soils based on pyrolysis gas chromatography–mass spectrometry. (<b>A</b>) The alpine meadow soil before incubation; (<b>B</b>) the alpine steppe soil before incubation; (<b>C</b>) the alpine meadow soil after incubation; (<b>D</b>) the alpine steppe soil after incubation.</p>
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<p>The compositions of lignin in alpine grassland soils before and after incubation. AM1 and AS1 are alpine meadow and alpine steppe before incubation; AM2 and AS2 are alpine meadow and alpine steppe after incubation.</p>
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<p>The relative abundance of phospholipid fatty acids in alpine grassland soils.</p>
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<p>The correlations between lignin and soil PLFA biomarkers in alpine grassland soils.</p>
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<p>Principal component analysis of lignin and PLFAs in alpine grassland soils. PLFA, phospholipid fatty acid.</p>
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15 pages, 3829 KiB  
Article
Development and Optimization of a Bromothymol Blue-Based PLA2 Assay Involving POPC-Based Self-Assemblies
by Shibbir Ahmed Khan and Marc A. Ilies
Int. J. Mol. Sci. 2024, 25(17), 9517; https://doi.org/10.3390/ijms25179517 - 1 Sep 2024
Viewed by 371
Abstract
Phospholipase A2 (PLA2) is a superfamily of phospholipase enzymes that dock at the water/oil interface of phospholipid assemblies, hydrolyzing the ester bond at the sn-2 position. The enzymatic activity of these enzymes differs based on the nature of the substrate, its supramolecular assemblies [...] Read more.
Phospholipase A2 (PLA2) is a superfamily of phospholipase enzymes that dock at the water/oil interface of phospholipid assemblies, hydrolyzing the ester bond at the sn-2 position. The enzymatic activity of these enzymes differs based on the nature of the substrate, its supramolecular assemblies (micelle, liposomes), and their composition, reflecting the interfacial nature of the PLA2s and requiring assays able to directly quantify this interaction of the enzyme(s) with these supramolecular assemblies. We developed and optimized a simple, universal assay method employing the pH-sensitive indicator dye bromothymol blue (BTB), in which different POPC (3-palmitoyl-2-oleoyl-sn-glycero-1-phosphocholine) self-assemblies (liposomes or mixed micelles with Triton X-100 at different molar ratios) were used to assess the enzymatic activity. We used this assay to perform a comparative analysis of PLA2 kinetics on these supramolecular assemblies and to determine the kinetic parameters of PLA2 isozymes IB and IIA for each supramolecular POPC assembly. This assay is suitable for assessing the inhibition of PLA2s with great accuracy using UV-VIS spectrophotometry, being thus amenable for screening of PLA2 enzymes and their substrates and inhibitors in conditions very similar to physiologic ones. Full article
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<p>Chemical structures of POPC and of Triton X-100. POPC is a pure phospholipid, fluid at room temperature (Tm = −2 °C), and Triton X100 (Tx) is an amphiphile that has well-defined physicochemical properties and a low CMC of 0.3 mM, which facilitates the formation of supramolecular structures, including mixed micelles with natural phospholipids, such as POPC and congeners.</p>
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<p>(<b>A</b>) Absorbance of BTB solution at 620 nm for BTB solutions with concentrations ranging from 0.01 mM to 2 mM and from 0.01 mM to 0.1 mM (linear dependence, insert). (<b>B</b>) Absorbance of BTB (0.05 mM) while adding HCl (100 nmols increments) to mimic the PLA2 hydrolysis reaction, revealing the maximum sensitivity of the assay.</p>
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<p>Effect of Ca<sup>2+</sup> concentration on sPLA2 IIA activity, assessed via BTB (0.05 mM) using POPC liposomes (25 µM) as the substrate and albumin (1 mg/mL) as the receiving phase for fatty acids produced in the ester hydrolysis, at 37 °C. Lines connecting the points are a guide for the eye.</p>
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<p>Effect of pH on PLA2 activity on POPC liposomes (25 µM), determined with buffers ranging from pH 5.2 to 9.5, in the presence of 1 mM Ca<sup>2+</sup>, 0.05 mM BTB, and 1 mg/mL albumin, at 37 °C. Lines connecting the points are a guide for the eye.</p>
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<p>Comparison of substrate processivity by PLA2 based on different POPC self-assemblies (liposomes vs. mixed micelles) at the same overall POPC substrate concentration (25 µM).</p>
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<p>Enzyme kinetics of PLA2 IB and PLA2 IIA using POPC-based liposomes: Michaelis–Menten kinetics and double reciprocal Lineweaver–Burke plots for PLA2 IB (<b>A</b>,<b>B</b>) and PLA2 IIA (<b>C</b>,<b>D</b>), together with a direct comparison of the kinetics of the two isozymes (<b>E</b>).</p>
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<p>Comparative enzyme kinetics of PLA2 IB on POPC-based mixed micelles Tx:POPC 1:1 (<b>A</b>) and Tx:POPC 1:2 (<b>B</b>), as well as for PLA2 IIA on POPC-based mixed micelles Tx:POPC 1:1 (<b>C</b>) and Tx:POPC 1:2 (<b>D</b>).</p>
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<p>Chemical structure of varespladib—an indole class PLA2-IIA-selective inhibitor [<a href="#B2-ijms-25-09517" class="html-bibr">2</a>].</p>
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<p>Determination of IC<sub>50</sub> of varespladib using POPC-based liposomes (<b>A</b>) and mixed micelles Tx:POPC 1:1 (<b>B</b>) and Tx:POPC 1:2 (<b>C</b>).</p>
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<p>Comparison of PLA2 IIA inhibition mechanism of varespladib in POPC liposomes (<b>A</b>) and mixed micelles Tx:POPC 1:1 (<b>B</b>) and Tx:POPC 1:2 (<b>C</b>).</p>
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<p>Most PLA2 assays are based either on the PLA2-mediated hydrolysis of natural phospholipids such as egg PCs (<b>A</b>), when the one quantifies the acid produced in the reaction, or on the PLA2-mediated hydrolysis of synthetic thioPCs (<b>B</b>), when the resulting lysothioPC further reacts with DTNB to yield the TNB final product, which is quantified spectrophotometrically at 412 nm.</p>
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12 pages, 4286 KiB  
Article
Thermosensitive Liposomes for Gemcitabine Delivery to Pancreatic Ductal Adenocarcinoma
by Cesar B. Aparicio-Lopez, Sarah Timmerman, Gabriella Lorino, Tatiana Rogers, Marla Pyle, Tej B. Shrestha and Matthew T. Basel
Cancers 2024, 16(17), 3048; https://doi.org/10.3390/cancers16173048 - 1 Sep 2024
Viewed by 412
Abstract
Treatment of pancreatic ductal adenocarcinoma with gemcitabine is limited by an increased desmoplasia, poor vascularization, and short plasma half-life. Heat-sensitive liposomes modified by polyethylene glycol (PEG; PEGylated liposomes) can increase plasma stability, reduce clearance, and decrease side effects. Nevertheless, translation of heat-sensitive liposomes [...] Read more.
Treatment of pancreatic ductal adenocarcinoma with gemcitabine is limited by an increased desmoplasia, poor vascularization, and short plasma half-life. Heat-sensitive liposomes modified by polyethylene glycol (PEG; PEGylated liposomes) can increase plasma stability, reduce clearance, and decrease side effects. Nevertheless, translation of heat-sensitive liposomes to the clinic has been hindered by the low loading efficiency of gemcitabine and by the difficulty of inducing hyperthermia in vivo. This study was designed to investigate the effect of phospholipid content on the stability of liposomes at 37 °C and their release under hyperthermia conditions; this was accomplished by employing a two-stage heating approach. First the liposomes were heated at a fast rate, then they were transferred to a holding bath. Thermosensitive liposomes formulated with DPPC: DSPC: PEG2k (80:15:5, mole%) exhibited minimal release of carboxyfluorescein at 37 °C over 30 min, indicating stability under physiological conditions. However, upon exposure to hyperthermic conditions (43 °C and 45 °C), these liposomes demonstrated a rapid and significant release of their encapsulated content. The encapsulation efficiency for gemcitabine was calculated at 16.9%. Additionally, fluorescent analysis during the removal of unencapsulated gemcitabine revealed an increase in pH. In vitro tests with BxPC3 and KPC cell models showed that these thermosensitive liposomes induced a heat-dependent cytotoxic effect comparable to free gemcitabine at temperatures above 41 °C. This study highlights the effectiveness of the heating mechanism and cell models in understanding the current challenges in developing gemcitabine-loaded heat-sensitive liposomes. Full article
(This article belongs to the Special Issue Multimodal Treatment for Pancreatic Cancer)
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Graphical abstract

Graphical abstract
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<p>To improve the heating protocol and reduce the undesired release, a ramp-up water bath is used to increase the temperature at a rapid rate (<b>B</b>). The temperature of the cell is correlated to a homologous plate equipped with four thermocouples (<b>C</b>). Once the desired temperature is reached, the plates are transferred to the regulatory bath (<b>A</b>).</p>
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<p>TEM image of synthesized liposomes.</p>
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<p>Release of CF as a function of time and temperature. (<b>A</b>) Release of CF at 37 °C versus time. (<b>B</b>) Temperature-dependent CF release from 80% DPPC fraction liposomes.</p>
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<p>Gemcitabine release. Gemcitabine release is temperature-dependent (<b>A</b>). Gemcitabine-loaded TSLs under normal vs. hyperthermia conditions for 20 min (<b>B</b>).</p>
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<p>Oregon Green pH determination. (<b>A</b>) Normalization of signal to remove concentration variation. (<b>B</b>) pH vs. ratio plot. (<b>C</b>) pH–fluorescence linear range. (<b>D</b>) Calculated protonation percentages of gem.</p>
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<p>MTT cytotoxicity studies. (<b>A</b>) KPC cell line. (<b>B</b>) BXPC3 cell line. ns: <span class="html-italic">p</span> &gt; 0.05; *: <span class="html-italic">p</span> ≤ 0.05; **: <span class="html-italic">p</span> ≤ 0.01; ***: <span class="html-italic">p</span> ≤ 0.001; ****: <span class="html-italic">p</span> ≤ 0.0001.</p>
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