International Journal of Molecular Sciences

35 pages, 2440 KiB

Open AccessReview

Rho GTPases in Intellectual Disability: From Genetics to Therapeutic Opportunities

by Valentina Zamboni, Rebecca Jones, Alessandro Umbach, Alessandra Ammoni, Maria Passafaro, Emilio Hirsch and Giorgio R. Merlo

Int. J. Mol. Sci. 2018, 19(6), 1821; https://doi.org/10.3390/ijms19061821 - 20 Jun 2018

Cited by 59 | Viewed by 9113

Abstract

Rho-class small GTPases are implicated in basic cellular processes at nearly all brain developmental steps, from neurogenesis and migration to axon guidance and synaptic plasticity. GTPases are key signal transducing enzymes that link extracellular cues to the neuronal responses required for the construction [...] Read more.

Rho-class small GTPases are implicated in basic cellular processes at nearly all brain developmental steps, from neurogenesis and migration to axon guidance and synaptic plasticity. GTPases are key signal transducing enzymes that link extracellular cues to the neuronal responses required for the construction of neuronal networks, as well as for synaptic function and plasticity. Rho GTPases are highly regulated by a complex set of activating (GEFs) and inactivating (GAPs) partners, via protein:protein interactions (PPI). Misregulated RhoA, Rac1/Rac3 and cdc42 activity has been linked with intellectual disability (ID) and other neurodevelopmental conditions that comprise ID. All genetic evidences indicate that in these disorders the RhoA pathway is hyperactive while the Rac1 and cdc42 pathways are consistently hypoactive. Adopting cultured neurons for in vitro testing and specific animal models of ID for in vivo examination, the endophenotypes associated with these conditions are emerging and include altered neuronal networking, unbalanced excitation/inhibition and altered synaptic activity and plasticity. As we approach a clearer definition of these phenotype(s) and the role of hyper- and hypo-active GTPases in the construction of neuronal networks, there is an increasing possibility that selective inhibitors and activators might be designed via PPI, or identified by screening, that counteract the misregulation of small GTPases and result in alleviation of the cognitive condition. Here we review all knowledge in support of this possibility. Full article

(This article belongs to the Special Issue Small GTPases)

► Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
Regulations of Rho GTPases at the growth cone, by GTPase-activating proteins (GAPs) and Guanine nucleotide Exchange Factors (GEFs) implicated in Intellectual Disability. Green and red boxes surround GEF and GAP proteins, respectively. Asterisks indicate that are mutated in Intellectual Disability (ID) and other human diseases comprising ID. Circled P indicates phosphorylation. Arrows indicate activation, T bars indicate inhibition. A representative small magnification image of a growth cone is provided in the inset (top left). ROCK, Rho kinase-LIM domain kinase; MLC, myosin light chain; PAK1-2-3, p21-activated kinase 1-2-3; LIMK1-2, Rho kinase-LIM domain kinase 1-2. Full article ">Figure 2
Regulations of Rho GTPases at the leading edge of a migrating neuron, by GAPs and GEFs implicated in Intellectual Disability. Green and red boxes surround GEF and GAP proteins, respectively. Circled P indicates phosphorylation. Arrows indicate activation, T bars indicate inhibition. A representative small magnification image of a migrating neuron with an evident leading edge is provided in the inset (top left). ROCK, Rho kinase-LIM domain kinase; MLC, myosin light chain; PAK1-2-3, p21-activated kinase 1-2-3; LIMK1-2, Rho kinase-LIM domain kinase 1-2. Full article ">Figure 3
Regulations of Rho GTPases at the dendritic spine of an excitatory synapse, by GAPs and GEFs implicated in Intellectual Disability. Green and red boxes surround GEF and GAP proteins, respectively. Asterisks indicate genes that are mutated in ID and other human diseases comprising ID. Circled P indicates phosphorylation. Arrows indicate activation, T bars indicate inhibition. A representative small magnification image of a dendritic spine is provided in the inset (top left). ROCK, Rho kinase-LIM domain kinase; RICS, Rho GTPase activating protein 32; DOCK10, dedicator of cytokinesis 10; RICH2, Rho GTPase activating protein 44; PAK1-2-3, p21-activated kinase 1-2-3; LIMK1-2, Rho kinase-LIM domain kinase 1-2. Full article ">

13 pages, 3009 KiB

Open AccessArticle

Does the Automatic Measurement of Interleukin 6 Allow for Prediction of Complications during the First 48 h of Acute Pancreatitis?

by Witold Kolber, Paulina Dumnicka, Małgorzata Maraj, Beata Kuśnierz-Cabala, Piotr Ceranowicz, Michał Pędziwiatr, Barbara Maziarz, Małgorzata Mazur-Laskowska, Marek Kuźniewski, Mateusz Sporek and Jerzy Walocha

Int. J. Mol. Sci. 2018, 19(6), 1820; https://doi.org/10.3390/ijms19061820 - 20 Jun 2018

Cited by 21 | Viewed by 5256

Abstract

Acute pancreatitis (AP) in most patients takes a course of self-limiting local inflammation. However, up to 20% of patients develop severe AP (SAP), associated with systemic inflammation and/or pancreatic necrosis. Early prediction of SAP allows for the appropriate intensive treatment of severe cases, [...] Read more.

Acute pancreatitis (AP) in most patients takes a course of self-limiting local inflammation. However, up to 20% of patients develop severe AP (SAP), associated with systemic inflammation and/or pancreatic necrosis. Early prediction of SAP allows for the appropriate intensive treatment of severe cases, which reduces mortality. Serum interleukin-6 (IL-6) has been proposed as a biomarker to assist early diagnosis of SAP, however, most data come from studies utilizing IL-6 measurements with ELISA. Our aim was to verify the diagnostic usefulness of IL-6 for the prediction of SAP, organ failure, and need for intensive care in the course of AP using a fully automated assay. The study included 95 adult patients with AP of various severity (29 mild, 58 moderately-severe, 8 severe) admitted to a hospital within 24 h from the onset of symptoms. Serum IL-6 was measured using electochemiluminescence immunoassay in samples collected on admission and on the next day of hospital stay. On both days, patients with SAP presented the highest IL-6 levels. IL-6 correlated positively with other inflammatory markers (white blood cell and neutrophil counts, C-reactive protein, procalcitonin), the markers of renal injury (kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin), and the markers of endothelial dysfunction (angiopoietin-2, soluble fms-like tyrosine kinase-1). IL-6 on admission significantly predicted SAP, vital organ failure, and the need for intensive care or death, with areas under the receiver operating curve between 0.75 and 0.78, not significantly different from multi-variable prognostic scores. The fully automated assay allows for fast and repeatable measurements of serum IL-6, enabling wider clinical use of this valuable biomarker. Full article

(This article belongs to the Special Issue Cell and Molecular Biology of Pancreatic Disorders)

► Show Figures

Figure 1

14 pages, 2727 KiB

Open AccessArticle

Effect of Surfactant Type and Sonication Energy on the Electrical Conductivity Properties of Nanocellulose-CNT Nanocomposite Films

by Sanna Siljander, Pasi Keinänen, Anna Räty, Karthik Ram Ramakrishnan, Sampo Tuukkanen, Vesa Kunnari, Ali Harlin, Jyrki Vuorinen and Mikko Kanerva

Int. J. Mol. Sci. 2018, 19(6), 1819; https://doi.org/10.3390/ijms19061819 - 20 Jun 2018

Cited by 36 | Viewed by 5877

Abstract

We present a detailed study on the influence of sonication energy and surfactant type on the electrical conductivity of nanocellulose-carbon nanotube (NFC-CNT) nanocomposite films. The study was made using a minimum amount of processing steps, chemicals and materials, to optimize the conductivity properties [...] Read more.

We present a detailed study on the influence of sonication energy and surfactant type on the electrical conductivity of nanocellulose-carbon nanotube (NFC-CNT) nanocomposite films. The study was made using a minimum amount of processing steps, chemicals and materials, to optimize the conductivity properties of free-standing flexible nanocomposite films. In general, the NFC-CNT film preparation process is sensitive concerning the dispersing phase of CNTs into a solution with NFC. In our study, we used sonication to carry out the dispersing phase of processing in the presence of surfactant. In the final phase, the films were prepared from the dispersion using centrifugal cast molding. The solid films were analyzed regarding their electrical conductivity using a four-probe measuring technique. We also characterized how conductivity properties were enhanced when surfactant was removed from nanocomposite films; to our knowledge this has not been reported previously. The results of our study indicated that the optimization of the surfactant type clearly affected the formation of freestanding films. The effect of sonication energy was significant in terms of conductivity. Using a relatively low 16 wt. % concentration of multiwall carbon nanotubes we achieved the highest conductivity value of 8.4 S/cm for nanocellulose-CNT films ever published in the current literature. This was achieved by optimizing the surfactant type and sonication energy per dry mass. Additionally, to further increase the conductivity, we defined a preparation step to remove the used surfactant from the final nanocomposite structure. Full article

(This article belongs to the Special Issue Synthesis and Applications of Biopolymer Composites)

► Show Figures

Graphical abstract

12 pages, 3185 KiB

Open AccessReview

Possible Molecular Targets of Novel Ruthenium Complexes in Antiplatelet Therapy

by Thanasekaran Jayakumar, Chia-Yuan Hsu, Themmila Khamrang, Chih-Hsuan Hsia, Chih-Wei Hsia, Manjunath Manubolu and Joen-Rong Sheu

Int. J. Mol. Sci. 2018, 19(6), 1818; https://doi.org/10.3390/ijms19061818 - 20 Jun 2018

Cited by 12 | Viewed by 4686

Abstract

In oncotherapy, ruthenium (Ru) complexes are reflected as potential alternatives for platinum compounds and have been proved as encouraging anticancer drugs with high efficacy and low side effects. Cardiovascular diseases (CVDs) are mutually considered as the number one killer globally, and thrombosis is [...] Read more.

In oncotherapy, ruthenium (Ru) complexes are reflected as potential alternatives for platinum compounds and have been proved as encouraging anticancer drugs with high efficacy and low side effects. Cardiovascular diseases (CVDs) are mutually considered as the number one killer globally, and thrombosis is liable for the majority of CVD-related deaths. Platelets, an anuclear and small circulating blood cell, play key roles in hemostasis by inhibiting unnecessary blood loss of vascular damage by making blood clot. Platelet activation also plays a role in cancer metastasis and progression. Nevertheless, abnormal activation of platelets results in thrombosis under pathological settings such as the rupture of atherosclerotic plaques. Thrombosis diminishes the blood supply to the heart and brain resulting in heart attacks and strokes, respectively. While currently used anti-platelet drugs such as aspirin and clopidogrel demonstrate efficacy in many patients, they exert undesirable side effects. Therefore, the development of effective therapeutic strategies for the prevention and treatment of thrombotic diseases is a demanding priority. Recently, precious metal drugs have conquered the subject of metal-based drugs, and several investigators have motivated their attention on the synthesis of various ruthenium (Ru) complexes due to their prospective therapeutic values. Similarly, our recent studies established that novel ruthenium-based compounds suppressed platelet aggregation via inhibiting several signaling cascades. Our study also described the structure antiplatelet-activity relationship (SAR) of three newly synthesized ruthenium-based compounds. This review summarizes the antiplatelet activity of newly synthesized ruthenium-based compounds with their potential molecular mechanisms. Full article

(This article belongs to the Special Issue Molecular Pharmacology and Pathology of Strokes)

► Show Figures

Figure 1

Figure 1
Synthetic procedure of the ligands (A) and its complexes (B) of TQ-1, TQ-2, TQ-3, TQ-5 and TQ-6; (C) Structures of ruthenium (II) methylimidazole complexes [Ru(MeIm)4(4npip)]2+ and [Ru(MeIm)4(4mopip)]2+. Full article ">Figure 1 Cont.
Synthetic procedure of the ligands (A) and its complexes (B) of TQ-1, TQ-2, TQ-3, TQ-5 and TQ-6; (C) Structures of ruthenium (II) methylimidazole complexes [Ru(MeIm)4(4npip)]2+ and [Ru(MeIm)4(4mopip)]2+. Full article ">Figure 2
General representation of the main targets and proposed mechanisms of action of ruthenium compounds as antiplatelet drugs. <img alt="Ijms 19 01818 i001" src="/ijms/ijms-19-01818/article_deploy/html/images/ijms-19-01818-i001.png"/> inhibits; <img alt="Ijms 19 01818 i002" src="/ijms/ijms-19-01818/article_deploy/html/images/ijms-19-01818-i002.png"/> blocks; <img alt="Ijms 19 01818 i003" src="/ijms/ijms-19-01818/article_deploy/html/images/ijms-19-01818-i003.png"/> decrease; <img alt="Ijms 19 01818 i004" src="/ijms/ijms-19-01818/article_deploy/html/images/ijms-19-01818-i004.png"/> increase. Full article ">Figure 3
Molecular targets of Ru-thio-chrysin to its inhibitory effects on platelet function. Full article ">

21 pages, 2754 KiB

Open AccessArticle

Studies of Microbiota Dynamics Reveals Association of “Candidatus Liberibacter Asiaticus” Infection with Citrus (Citrus sinensis) Decline in South of Iran

by Alessandro Passera, Hamidreza Alizadeh, Mehdi Azadvar, Fabio Quaglino, Asma Alizadeh, Paola Casati and Piero A. Bianco

Int. J. Mol. Sci. 2018, 19(6), 1817; https://doi.org/10.3390/ijms19061817 - 20 Jun 2018

Cited by 11 | Viewed by 4047

Abstract

Citrus Decline Disease was recently reported to affect several citrus species in Iran when grafted on a local rootstock variety, Bakraee. Preliminary studies found “Candidatus Phytoplasma aurantifoliae” and “Candidatus Liberibacter asiaticus” as putative etiological agents, but were not ultimately able to [...] Read more.

Citrus Decline Disease was recently reported to affect several citrus species in Iran when grafted on a local rootstock variety, Bakraee. Preliminary studies found “Candidatus Phytoplasma aurantifoliae” and “Candidatus Liberibacter asiaticus” as putative etiological agents, but were not ultimately able to determine which one, or if an association of both, were causing the disease. The current study has the aim of characterizing the microbiota of citrus plants that are either asymptomatic, showing early symptoms, or showing late symptoms through amplification of the V1–V3 region of 16S rRNA gene using an Illumina sequencer in order to (i) clarify the etiology of the disease, and (ii) describe the microbiota associated to different symptom stages. Our results suggest that liberibacter may be the main pathogen causing Citrus Decline Disease, but cannot rule out the possibility of phytoplasma being involved as well. The characterization of microbiota shows that the leaves show only two kinds of communities, either symptomatic or asymptomatic, while roots show clear distinction between early and late symptoms. These results could lead to the identification of bacteria that are related to successful plant defense response and, therefore, to immunity to the Citrus Decline Disease. Full article

(This article belongs to the Special Issue Plant Innate Immunity 2.0)

► Show Figures

Figure 1

14 pages, 557 KiB

Open AccessReview

Diabetic Retinopathy: Pathophysiology and Treatments

by Wei Wang and Amy C. Y. Lo

Int. J. Mol. Sci. 2018, 19(6), 1816; https://doi.org/10.3390/ijms19061816 - 20 Jun 2018

Cited by 843 | Viewed by 43519

Abstract

Diabetic retinopathy (DR) is the most common complication of diabetes mellitus (DM). It has long been recognized as a microvascular disease. The diagnosis of DR relies on the detection of microvascular lesions. The treatment of DR remains challenging. The advent of anti-vascular endothelial [...] Read more.

Diabetic retinopathy (DR) is the most common complication of diabetes mellitus (DM). It has long been recognized as a microvascular disease. The diagnosis of DR relies on the detection of microvascular lesions. The treatment of DR remains challenging. The advent of anti-vascular endothelial growth factor (VEGF) therapy demonstrated remarkable clinical benefits in DR patients; however, the majority of patients failed to achieve clinically-significant visual improvement. Therefore, there is an urgent need for the development of new treatments. Laboratory and clinical evidence showed that in addition to microvascular changes, inflammation and retinal neurodegeneration may contribute to diabetic retinal damage in the early stages of DR. Further investigation of the underlying molecular mechanisms may provide targets for the development of new early interventions. Here, we present a review of the current understanding and new insights into pathophysiology in DR, as well as clinical treatments for DR patients. Recent laboratory findings and related clinical trials are also reviewed. Full article

(This article belongs to the Special Issue Retinal Diseases: Bridging Basic and Clinical Research)

► Show Figures

Figure 1

11 pages, 1792 KiB

Open AccessArticle

Exploring the Mechanism of Inhibition of Au Nanoparticles on the Aggregation of Amyloid-β(16-22) Peptides at the Atom Level by All-Atom Molecular Dynamics

by Menghua Song, Yunxiang Sun, Yin Luo, Yanyan Zhu, Yongsheng Liu and Huiyu Li

Int. J. Mol. Sci. 2018, 19(6), 1815; https://doi.org/10.3390/ijms19061815 - 20 Jun 2018

Cited by 39 | Viewed by 5511

Abstract

The abnormal self-assembly of the amyloid-β peptide into toxic β-rich aggregates can cause Alzheimer’s disease. Recently, it has been shown that small gold nanoparticles (AuNPs) inhibit Aβ aggregation and fibrillation by slowing down the nucleation process in experimental studies. However, the effects of [...] Read more.

The abnormal self-assembly of the amyloid-β peptide into toxic β-rich aggregates can cause Alzheimer’s disease. Recently, it has been shown that small gold nanoparticles (AuNPs) inhibit Aβ aggregation and fibrillation by slowing down the nucleation process in experimental studies. However, the effects of AuNPs on Aβ oligomeric structures are still unclear. In this study, we investigate the conformation of Aβ(16-22) tetramers/octamers in the absence and presence of AuNPs using extensive all-atom molecular-dynamics simulations in explicit solvent. Our studies demonstrate that the addition of AuNPs into Aβ(16-22) solution prevents β-sheet formation, and the inhibition depends on the concentration of Aβ(16-22) peptides. A detailed analysis of the Aβ(16-22)/Aβ(16-22)/water/AuNPs interactions reveals that AuNPs inhibit the β-sheet formation resulting from the same physical forces: hydrophobic interactions. Overall, our computational study provides evidence that AuNPs are likely to inhibit Aβ(16-22) and full-length Aβ fibrillation. Thus, this work provides theoretical insights into the development of inorganic nanoparticles as drug candidates for treatment of AD. Full article

(This article belongs to the Special Issue Translating Gold Nanoparticles to Diagnostics and Therapeutics)

► Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
Detailed analysis of a representative molecular dynamics (MD) trajectory starting from the initial state for the Aβ-tetramer system (A), Aβ-tetramer + AuNPs system(B), Aβ-octamer system (C), and Aβ-octamer + AuNPs system (D). Snapshots at seven different time points and the top view of the snapshot generated at t = 500 ns. The peptides are represented as cartoons, with the β sheet in yellow, the coil in cyan and the other secondary structure in white and purple. The AuNPs are in van der Waals (vdW) representation in pink. For clarity, counter ions and water molecules are not shown. Full article ">Figure 2
Calculated β-sheet probability of each residue of Aβ (16-22) peptides in (A) the Aβ tetramer system (red) and Aβ tetramer + AuNPs system (black) and (B) the Aβ octamer system (red) and the Aβ octamer + AuNPs system (black). Full article ">Figure 3
Representative conformations of the top two most-populated clusters for the Aβ tetramer in the absence (A) and presence (B) of AuNPs. Side-chain-side-chain (SC-SC) and main-chain-main-chain (MC-MC) contact probability maps for Aβ tetramer in the absence (C,E) and presence (D,F) of AuNPs. The Aβ tetramer is shown in new cartoon representation. The peptides are colored in yellow. The AuNPs are in vdW representation and colored in pink. Full article ">Figure 4
Probability distribution of the minimum distance between the side chain of each residue.and AuNPs’ surface in the Aβ tetramer/octamer + AuNPs system. The distance between AuNPs’ surface and (A) K16, E22, (B) L17, V18, A21, (C)F19, F20. Full article ">Figure 5
Solvent accessible surface area of each residue as a function of amino acid residue (A) for the Aβ tetramer (B) and the Aβ octamer in the absence (black) and presence (red) of AuNPs. Residue-based binding interaction analysis: contact probability (C,D) and binding free energy (in kcal mol−1) (E,F). Full article ">

15 pages, 2699 KiB

Open AccessArticle

Yeast-Based Screen to Identify Natural Compounds with a Potential Therapeutic Effect in Hailey-Hailey Disease

by Graziella Ficociello, Azzurra Zonfrilli, Samantha Cialfi, Claudio Talora and Daniela Uccelletti

Int. J. Mol. Sci. 2018, 19(6), 1814; https://doi.org/10.3390/ijms19061814 - 20 Jun 2018

Cited by 6 | Viewed by 5289

Abstract

The term orthodisease defines human disorders in which the pathogenic gene has orthologs in model organism genomes. Yeasts have been instrumental for gaining insights into the molecular basis of many human disorders, particularly those resulting from impaired cellular metabolism. We and others have [...] Read more.

The term orthodisease defines human disorders in which the pathogenic gene has orthologs in model organism genomes. Yeasts have been instrumental for gaining insights into the molecular basis of many human disorders, particularly those resulting from impaired cellular metabolism. We and others have used yeasts as a model system to study the molecular basis of Hailey-Hailey disease (HHD), a human blistering skin disorder caused by haploinsufficiency of the gene ATP2C1 the orthologous of the yeast gene PMR1. We observed that K. lactis cells defective for PMR1 gene share several biological similarities with HHD derived keratinocytes. Based on the conservation of ATP2C1/PMR1 function from yeast to human, here we used a yeast-based assay to screen for molecules able to influence the pleiotropy associated with PMR1 deletion. We identified six compounds, Kaempferol, Indirubin, Lappaconite, Cyclocytidine, Azomycin and Nalidixic Acid that induced different major shape phenotypes in K. lactis. These include mitochondrial and the cell-wall morphology-related phenotypes. Interestingly, a secondary assay in mammalian cells confirmed activity for Kaempferol. Indeed, this compound was also active on human keratinocytes depleted of ATP2C1 function by siRNA-treatment used as an in-vitro model of HHD. We found that Kaempferol was a potent NRF2 regulator, strongly inducing its expression and its downstream target NQO1. In addition, Kaempferol could decrease oxidative stress of ATP2C1 defective keratinocytes, characterized by reduced NRF2-expression. Our results indicated that the activation of these pathways might provide protection to the HHD-skin cells. As oxidative stress plays pivotal roles in promoting the skin lesions of Hailey-Hailey, the NRF2 pathway could be a viable therapeutic target for HHD. Full article

(This article belongs to the Special Issue Rare Diseases: Molecular Mechanisms and Therapeutic Strategies)

► Show Figures

Graphical abstract

24 pages, 988 KiB

Open AccessReview

Lead (Pb) Exposure Enhances Expression of Factors Associated with Inflammation

by Emilia Metryka, Karina Chibowska, Izabela Gutowska, Anna Falkowska, Patrycja Kupnicka, Katarzyna Barczak, Dariusz Chlubek and Irena Baranowska-Bosiacka

Int. J. Mol. Sci. 2018, 19(6), 1813; https://doi.org/10.3390/ijms19061813 - 20 Jun 2018

Cited by 145 | Viewed by 8977

Abstract

The human immune system is constantly exposed to xenobiotics and pathogens from the environment. Although the mechanisms underlying their influence have already been at least partially recognized, the effects of some factors, such as lead (Pb), still need to be clarified. The results [...] Read more.

The human immune system is constantly exposed to xenobiotics and pathogens from the environment. Although the mechanisms underlying their influence have already been at least partially recognized, the effects of some factors, such as lead (Pb), still need to be clarified. The results of many studies indicate that Pb has a negative effect on the immune system, and in our review, we summarize the most recent evidence that Pb can promote inflammatory response. We also discuss possible molecular and biochemical mechanisms of its proinflammatory action, including the influence of Pb on cytokine metabolism (interleukins IL-2, IL-4, IL-8, IL-1b, IL-6), interferon gamma (IFNγ), and tumor necrosis factor alpha (TNF-α); the activity and expression of enzymes involved in the inflammatory process (cyclooxygenases); and the effect on selected acute phase proteins: C-reactive protein (CRP), haptoglobin, and ceruloplasmin. We also discuss the influence of Pb on the immune system cells (T and B lymphocytes, macrophages, Langerhans cells) and the secretion of IgA, IgE, IgG, histamine, and endothelin. Full article

(This article belongs to the Section Molecular Toxicology)

► Show Figures

Figure 1

Figure 1
Model of lead (Pb2+)-induced activation of the IL-8 gene. The diagram presents a signaling pathway leading to the induction of the IL-8 gene in human AGS cells (human caucasian gastric adenocarcinoma) after the administration of 0.1 μM Pb(NO3)2. Pb2+ activates the epidermal growth factor receptor (EGFR) and p42/44 mitogen activated protein (MAP) kinase phosphorylation, which then activates the protein heterodimeric transcriptional factor AP-1 (containing the c-jun protein), resulting in the activation of IL-8 gene expression. The use of EGFR inhibitors (PD153035 and AG1478) resulted in a decrease in IL-8 gene expression, but EGFR inhibitors were unable to fully abolish Pb(NO3)2-induced IL-8 gene expression. The use of a MAP kinase kinase (MEK) inhibitor (PD98059) significantly suppressed IL-8 gene expression. Full article ">Figure 2
Mechanism of activation and inactivation Nrf 2 by Pb2+. In physiological conditions, Nrf2 binds to its inhibitor, Kelch-like ECH-associated protein 1 (Keap1). This is followed by the dimerization and then sequestration of Nrf2 in the cytoplasm. The Keap1–Nrf2 complex connects ubiquitin (via the Cul 3-dependent ligase) and is recognized by the 26S proteosome, where the Nrf2 transcription factor is degraded. After exposure to Pb2+, Nrf2 is released from the Keap1–Nrf2 complex, and translocated to the nucleus, where a small Maf protein attaches forming a heterodimer and CREB-binding protein (CBP). The incorporation of the newly formed complex into DNA initiates the transcription of antioxidant response genes and IL-8 gene results in enhanced reactive oxygen species (ROS) and IL-8 synthesis. Full article ">Figure 3
The signaling pathway that results in the production of tumor necrosis factor alpha (TNF-α) in macrophages after the stimulation by lead and lipopolysaccharide (LPS). Lead increases the expression of TNF-α in LPS-treated cells via post-transcriptional mechanisms. It thus increases the effect of lipopolysaccharide (LPS) that is uptaken by the CD14 receptor (cluster of differentiation 14) and its co-receptor TLR 4 (Toll-like receptor TLR 4). The diagram shows some of the transmitters potentially mediating the regulation of TNF-α expression. The signal is transmitted via the MyD88 adapter protein (myeloid differentiation primary response gene 88). One of the activated pathways is the MAPK pathway. MEK1/2 (mitogen-activated protein kinase kinase), MAPK (mitogen-activated protein kinases), and activator protein 1 (AP-1) are activated. The NF-κB factor (nuclear factor kappa B) activation pathway is also stimulated by the regulation of IKKs (IκB kinase) activity. The resulting AP-1 and NF-κB lead to enhanced transcription of TNF-α mRNA. PI3K–AKT pathway is also activated. Attachment of LPS to the receptor leads to the phosphorylation of PI3K (phosphoinositide 3-kinase), which then activates AKT (protein kinase B). There is a mutual adjustment between the NF-κB and PI3K–AKT signaling pathways. The activation of the above-mentioned signaling pathways by LPS and Pb results in enhanced TNF-α synthesis. Full article ">

25 pages, 720 KiB

Open AccessReview

Anti-Inflammatory Effects of Resveratrol: Mechanistic Insights

by Diego De Sá Coutinho, Maria Talita Pacheco, Rudimar Luiz Frozza and Andressa Bernardi

Int. J. Mol. Sci. 2018, 19(6), 1812; https://doi.org/10.3390/ijms19061812 - 20 Jun 2018

Cited by 203 | Viewed by 11785

Abstract

Inflammation is the principal response invoked by the body to address injuries. Despite inflammation constituting a crucial component of tissue repair, it is well known that unchecked or chronic inflammation becomes deleterious, leading to progressive tissue damage. Studies over the past years focused [...] Read more.

Inflammation is the principal response invoked by the body to address injuries. Despite inflammation constituting a crucial component of tissue repair, it is well known that unchecked or chronic inflammation becomes deleterious, leading to progressive tissue damage. Studies over the past years focused on foods rich in polyphenols with anti-inflammatory and immunomodulatory properties, since inflammation was recognized to play a central role in several diseases. In this review, we discuss the beneficial effects of resveratrol, the most widely investigated polyphenol, on cancer and neurodegenerative, respiratory, metabolic, and cardiovascular diseases. We highlight how resveratrol, despite its unfavorable pharmacokinetics, can modulate the inflammatory pathways underlying those diseases, and we identify future opportunities for the evaluation of its clinical feasibility. Full article

(This article belongs to the Special Issue Natural Anti-Inflammatory Agents 2018)

► Show Figures

Graphical abstract

13 pages, 1557 KiB

Open AccessReview

Role of Membrane Cholesterol Levels in Activation of Lyn upon Cell Detachment

by Takao Morinaga, Noritaka Yamaguchi, Yuji Nakayama, Masatoshi Tagawa and Naoto Yamaguchi

Int. J. Mol. Sci. 2018, 19(6), 1811; https://doi.org/10.3390/ijms19061811 - 19 Jun 2018

Cited by 6 | Viewed by 5717

Abstract

Cholesterol, a major component of the plasma membrane, determines the physical
properties of biological membranes and plays a critical role in the assembly of membrane
microdomains. Enrichment or deprivation of membrane cholesterol affects the activities of many
signaling molecules at the plasma membrane. [...] Read more.

Cholesterol, a major component of the plasma membrane, determines the physical
properties of biological membranes and plays a critical role in the assembly of membrane
microdomains. Enrichment or deprivation of membrane cholesterol affects the activities of many
signaling molecules at the plasma membrane. Cell detachment changes the structure of the plasma
membrane and influences the localizations of lipids, including cholesterol. Recent studies showed
that cell detachment changes the activities of a variety of signaling molecules. We previously reported
that the localization and the function of the Src-family kinase Lyn are critically regulated by its
membrane anchorage through lipid modifications. More recently, we found that the localization and
the activity of Lyn were changed upon cell detachment, although the manners of which vary between
cell types. In this review, we highlight the changes in the localization of Lyn and a role of cholesterol
in the regulation of Lyn’s activation following cell detachment.
Full article

(This article belongs to the Special Issue Cholesterol and Lipoprotein Metabolism)

► Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
Trafficking of Src-family kinases. (a) The black arrow indicates biosynthetic trafficking of Lyn kinase. Distributions of c-Src and Fyn differ from that of Lyn. The dashed arrows indicate the translocation of c-Src between the plasma membrane and endosomes. The red and blue wavy lines represent myristic acids and palmitic acids, respectively; (b) Loss of cell–scaffold interactions did not internalize Lyn from the plasma membrane in HeLa S3 cells but internalizes c-Src and Fyn in NIH3T3 cells, whereas caveolin and cholesterol were internalized from the plasma membrane after cell detachment in both cell lines. However, loss of cell–cell interactions is capable of internalizing Lyn in MDCK cells. Full article ">Figure 2
Fractionations of cellular membranes. (a) Detergent-based fractionation. An ideal membrane fragment consists of detergent-insoluble portion (left half) and detergent-soluble portion (right half). The proteins in detergent-soluble membranes are solubilized with an appropriate concentration of detergent and separated by density gradient fractionation. (b) (i) Membrane fragments comprising differential ratios of proteins to lipids were separated by density gradient fractionation; (ii) the distribution pattern of a given protein of interest in density gradient fractionation (green area) reflects the density of the membrane segments harboring the protein of interest (green circle). Full article ">Figure 3
Cell detachment activates Lyn through cholesterol depletion. Cell detachment causes internalization of some lipid raft-related molecules, including caveolin and cholesterol, in the plasma membrane. Cholesterol depletion affects the characteristics of the membrane segments harboring Lyn, which is associated with activation of Lyn in suspended cells. Full article ">

13 pages, 1643 KiB

Open AccessArticle

Differential Expression and Pathway Analysis in Drug-Resistant Triple-Negative Breast Cancer Cell Lines Using RNASeq Analysis

by Safa Shaheen, Febin Fawaz, Shaheen Shah and Dietrich Büsselberg

Int. J. Mol. Sci. 2018, 19(6), 1810; https://doi.org/10.3390/ijms19061810 - 19 Jun 2018

Cited by 23 | Viewed by 9438

Abstract

Triple-negative breast cancer (TNBC) is among the most notorious types of breast cancer, the treatment of which does not give consistent results due to the absence of the three receptors (estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 [...] Read more.

Triple-negative breast cancer (TNBC) is among the most notorious types of breast cancer, the treatment of which does not give consistent results due to the absence of the three receptors (estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) as well as high amount of molecular variability. Drug resistance also contributes to treatment unresponsiveness. We studied differentially expressed genes, their biological roles, as well as pathways from RNA-Seq datasets of two different TNBC drug-resistant cell lines of Basal B subtype SUM159 and MDA-MB-231 treated with drugs JQ1 and Dexamethasone, respectively, to elucidate the mechanism of drug resistance. RNA sequencing(RNA-Seq) data analysis was done using edgeR which is an efficient program for determining the most significant Differentially Expressed Genes (DEGs), Gene Ontology (GO) terms, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. iPathway analysis was further used to obtain validated results using analysis that takes into consideration type, function, and interactions of genes in the pathway. The significant similarities and differences throw light into the molecular heterogeneity of TNBC, giving clues into the aspects that can be focused to overcome drug resistance. From this study, cytokine-cytokine receptor interaction pathway appeared to be a key factor in TNBC drug resistance. Full article

(This article belongs to the Special Issue New Strategies to Overcome Resistance to Chemotherapy and Immune System in Cancer)

► Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
Multidimensional scaling plots (a) for JQ1 treatment; (b) for Dexamethasone treatment. s1—JQ1 sensitive-3 h treatment, s2—JQ1 sensitive-3 h treatment, s3—JQ1 sensitive-24 h treatment, s4—JQ1 sensitive-24 h treatment, r1—JQ1 resistant-3 h treatment, r2—JQ1 resistant-3 h treatment, r3—JQ1 resistant-24 h treatment, r4—JQ1 resistant-24 h treatment, ctrl1—control 1, ctrl2—control 2, dex2_1—Dexamethasone-2 h treatment, dex2_2—Dexamethasone-2 h treatment, dex4_1—Dexamethasone-4 h treatment and dex4_2—Dexamethasone-4 h treatment. Full article ">Figure 2
Biological Coefficient of Variation plots: (a) For JQ1 treatment; (b) For Dexamethasone treatment. CPM- counts per million. Full article ">Figure 2 Cont.
Biological Coefficient of Variation plots: (a) For JQ1 treatment; (b) For Dexamethasone treatment. CPM- counts per million. Full article ">Figure 3
Heat maps: (a) For 24 h of JQ1 treatment; (b) For four hours of Dexamethasone treatment. Full article ">Figure 4
Volcano plots: (a) For 24 h of JQ1 treatment. DE thresholds: Fold change 0.6, p-value 0.05.; (b) For four hours of Dex treatment. x-axis: log fold change (log FC), y-axis: negative logarithm of adjusted p-value -log10 (adjPVal). DE thresholds: Fold change 0.6, p-value 0.05. Full article ">Figure 5
Perturbation (y-axis) vs. Overrepresentation (x-axis) reveals disrupted pathways: (a) At 24 h of JQ1 treatment; (b) At four hours of Dexamethasone treatment. The size of each dot denotes the number of genes in the pathway. The x-axis measures p-values obtained using the classical over-representation analysis (pORA). The y-axis represents the p-values obtained from total perturbation accumulation (pAcc) in the pathway. Yellow: Cytokine-cytokine receptor interaction pathway, Red: Significantly enriched pathways, Black: Non-significantly enriched pathways. Full article ">

13 pages, 2899 KiB

Open AccessArticle

Diethyl Blechnic, a Novel Natural Product Isolated from Salvia miltiorrhiza Bunge, Inhibits Doxorubicin-Induced Apoptosis by Inhibiting ROS and Activating JNK1/2

by Jie Yu, Hongwei Gao, Chuanhong Wu, Qiong-Ming Xu, Jin-Jian Lu and Xiuping Chen

Int. J. Mol. Sci. 2018, 19(6), 1809; https://doi.org/10.3390/ijms19061809 - 19 Jun 2018

Cited by 19 | Viewed by 4490

Abstract

Doxorubicin (DOX) is a widely used antineoplastic agent in clinics. However, its clinical application is largely limited by its cardiotoxicity. Diethyl blechnic (DB) is a novel compound isolated from Salvia miltiorrhiza Bunge. Here, we study the effect of DB on DOX-induced cardiotoxicity and [...] Read more.

Doxorubicin (DOX) is a widely used antineoplastic agent in clinics. However, its clinical application is largely limited by its cardiotoxicity. Diethyl blechnic (DB) is a novel compound isolated from Salvia miltiorrhiza Bunge. Here, we study the effect of DB on DOX-induced cardiotoxicity and its underlying mechanisms. Cellular viability was tested by 3-[-4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) and protein level was evaluated by Western blotting. 5,5’,6,6’-tetrachloro-1,1’,3,3’-tetraethylbenzimidazolylcarbocyanine iodide (JC-1) staining was performed to determine the mitochondrial membrane potential (MMP). Hoechst 33342 staining and TUNEL staining was performed to test the apoptosis. Reactive oxygen species (ROS) generation was investigated by using flow cytometry. DB significantly inhibited DOX-induced apoptosis in H9c2 cells and primary cultured cardiomyocytes. Moreover, DB decreased cell apoptotic morphological changes and reversed the mitochondrial membrane potential induced by DOX. Meanwhile, pre-treatment with DB increased the expression levels of B-cell lymphoma 2 (Bcl-2), B-cell lymphoma-extra-large (Bcl-xl), and survivin and reduced the expression levels of Bcl-2-associated X protein (Bax), p-p53, cytochrome c (cyt c), and cleaved-caspase 3, 7, 8, 9 in the protein levels in DOX-treated H9c2 cells. Furthermore, DB suppressed ROS generation. The DB-mediated protective effects were accompanied by increased c-Jun N-terminal kinase1/2 (JNK1/2) expression. In addition, SP600125, the inhibitor of JNK1/2, abolished the protective effect of DB. We concluded that DB protected cardiomyocytes against DOX-induced cytotoxicity by inhibiting ROS and activating the JNK1/2 pathway. Therefore, DB is a promising candidate as a cardioprotective agent against DOX-induced cardiotoxicity. Full article

(This article belongs to the Special Issue Free Radicals and Oxidants in Pathogenesis)

► Show Figures

Graphical abstract

25 pages, 3259 KiB

Open AccessArticle

Co-Expression Network Analysis of AMPK and Autophagy Gene Products during Adipocyte Differentiation

by Mahmoud Ahmed, Jin Seok Hwang, Trang Huyen Lai, Sahib Zada, Huynh Quoc Nguyen, Trang Min Pham, Miyong Yun and Deok Ryong Kim

Int. J. Mol. Sci. 2018, 19(6), 1808; https://doi.org/10.3390/ijms19061808 - 19 Jun 2018

Cited by 8 | Viewed by 6033

Abstract

Autophagy is involved in the development and differentiation of many cell types. It is essential for the pre-adipocytes to respond to the differentiation stimuli and may contribute to reorganizing the intracellulum to adapt the morphological and metabolic demands. Although AMPK, an energy sensor, [...] Read more.

Autophagy is involved in the development and differentiation of many cell types. It is essential for the pre-adipocytes to respond to the differentiation stimuli and may contribute to reorganizing the intracellulum to adapt the morphological and metabolic demands. Although AMPK, an energy sensor, has been associated with autophagy in several cellular processes, how it connects to autophagy during the adipocyte differentiation remains to be investigated. Here, we studied the interaction between AMPK and autophagy gene products at the mRNA level during adipocyte differentiation using public-access datasets. We used the weighted-gene co-expression analysis to detect and validate multiple interconnected modules of co-expressed genes in a dataset of MDI-induced 3T3-L1 pre-adipocytes. These modules were found to be highly correlated with the differentiation course of the adipocytes. Several novel interactions between AMPK and autophagy gene products were identified. Together, it is possible that AMPK-autophagy interaction is temporally and locally modulated in response to the differentiation stimuli. Full article

(This article belongs to the Special Issue AMP-Activated Protein Kinase Signalling)

► Show Figures

Graphical abstract

21 pages, 4835 KiB

Open AccessArticle

Collagen as Coating Material for 45S5 Bioactive Glass-Based Scaffolds for Bone Tissue Engineering

by Jasmin Hum and Aldo R. Boccaccini

Int. J. Mol. Sci. 2018, 19(6), 1807; https://doi.org/10.3390/ijms19061807 - 19 Jun 2018

Cited by 54 | Viewed by 8395

Abstract

Highly porous 45S5 bioactive glass-based scaffolds were fabricated by the foam replica technique and coated with collagen by a novel method. After an initial cleaning step of the bioactive glass surface to expose reactive –OH groups, samples were surface functionalized by (3-aminopropyl)triethoxysilane (APTS). [...] Read more.

Highly porous 45S5 bioactive glass-based scaffolds were fabricated by the foam replica technique and coated with collagen by a novel method. After an initial cleaning step of the bioactive glass surface to expose reactive –OH groups, samples were surface functionalized by (3-aminopropyl)triethoxysilane (APTS). Functionalized scaffolds were immersed in a collagen solution, left for gelling at 37 °C, and dried at room temperature. The collagen coating was further stabilized by crosslinking with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxysuccinimide (NHS). Applying this coating method, a layer thickness of a few micrometers was obtained without affecting the overall scaffold macroporosity. In addition, values of compressive strength were enhanced by a factor of five, increasing from 0.04 ± 0.02 MPa for uncoated scaffolds to 0.18 ± 0.03 MPa for crosslinked collagen-coated scaffolds. The composite material developed in this study exhibited positive cell (MG-63) viability as well as suitable cell attachment and proliferation on the surface. The combination of bioactivity, mechanical competence, and cellular response makes this novel scaffold system attractive for bone tissue engineering. Full article

(This article belongs to the Special Issue Novel Biomaterials for Tissue Engineering 2018)

► Show Figures

Figure 1

21 pages, 6664 KiB

Open AccessArticle

5-Azacitidine Induces Cell Death in a Tissue Culture of Brachypodium distachyon

by Alexander Betekhtin, Anna Milewska-Hendel, Lukasz Chajec, Magdalena Rojek, Katarzyna Nowak, Jolanta Kwasniewska, Elzbieta Wolny, Ewa Kurczynska and Robert Hasterok

Int. J. Mol. Sci. 2018, 19(6), 1806; https://doi.org/10.3390/ijms19061806 - 19 Jun 2018

Cited by 19 | Viewed by 5823

Abstract

Morphological and histological observations revealed that, at a concentration of 50 µM, 5-azacitidine (5-azaC) totally inhibited the induction of embryogenic masses (EM), while the cultivation of explants (zygotic embryos; ZEs) in the presence of 5 µM of 5-azaC led to the formation of [...] Read more.

Morphological and histological observations revealed that, at a concentration of 50 µM, 5-azacitidine (5-azaC) totally inhibited the induction of embryogenic masses (EM), while the cultivation of explants (zygotic embryos; ZEs) in the presence of 5 µM of 5-azaC led to the formation of a callus with EM in 10% of the cases. Transmission electron microscopy (TEM) analyzes revealed the presence of the morphological and ultrastructural features that are typical for the vacuolar type of cell death in the callus cells that were treated. A TUNEL assay confirmed the presence of DNA double-strand breaks for the callus cells that had been treated with both 5 and 50 µM 5-azaC concentrations. Analysis of the gene expression of selected cell death markers demonstrated a reduced expression of metacaspase, protein executer 1 (EX1), and thioredoxin (TRX) in the callus cells that had been treated compared to the control culture. The strongest increase in the gene activity was characteristic for glutathione S-transferase (GST). Our studies also included an analysis of the distribution of some arabinogalactan proteins (AGPs) and extensin epitopes, which can be used as markers of cells that are undergoing death in a Brachypodium distachyon tissue culture. Full article

(This article belongs to the Section Molecular Plant Sciences)

► Show Figures

Graphical abstract

17 pages, 2320 KiB

Open AccessArticle

Inter-Individual Variability in Acute Toxicity of R-Pulegone and R-Menthofuran in Human Liver Slices and Their Influence on miRNA Expression Changes in Comparison to Acetaminophen

by Tomáš Zárybnický, Petra Matoušková, Bibiána Lancošová, Zdeněk Šubrt, Lenka Skálová and Iva Boušová

Int. J. Mol. Sci. 2018, 19(6), 1805; https://doi.org/10.3390/ijms19061805 - 19 Jun 2018

Cited by 18 | Viewed by 4792

Abstract

Monoterpenes R-pulegone (PUL) and R-menthofuran (MF), abundant in the Lamiaceae family, are frequently used in herb and food products. Although their hepatotoxicity was shown in rodent species, information about their effects in human liver has been limited. The aim of our study was [...] Read more.

Monoterpenes R-pulegone (PUL) and R-menthofuran (MF), abundant in the Lamiaceae family, are frequently used in herb and food products. Although their hepatotoxicity was shown in rodent species, information about their effects in human liver has been limited. The aim of our study was to test the effects of PUL, MF and acetaminophen (APAP, as a reference compound) on cell viability and microRNA (miRNA) expression in human precision-cut liver slices. Slices from five patients were used to follow up on the inter-individual variability. PUL was toxic in all liver samples (the half-maximal effective concentration was 4.0 µg/mg of tissue), while MF and surprisingly APAP only in two and three liver samples, respectively. PUL also changed miRNA expression more significantly than MF and APAP. The most pronounced effect was a marked decrease of miR-155-5p expression caused by PUL even in non-toxic concentrations in all five liver samples. Our results showed that PUL is much more toxic than MF and APAP in human liver and that miR-155-5p could be a good marker of PUL early hepatotoxicity. Marked inter-individual variabilities in all our results demonstrate the high probability of significant differences in the hepatotoxicity of tested compounds among people. Full article

(This article belongs to the Special Issue Hepatotoxicity: Molecular Mechanisms and Pathophysiology)

► Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
Structural formulas of studied monoterpenes and a reference compound acetaminophen. Full article ">Figure 2
Inter-individual differences in the effect of R-pulegone, R-menthofuran and acetaminophen on viability of PCLS from five patients (1–5) after 24 h (n = 3), determined by ATP content. Results are presented as the mean ± SD. Statistical analyses were performed using one-way ANOVA with Dunnett’s test: p < 0.05 (*); p < 0.001 (**); p < 0.0001 (***). Full article ">Figure 3
Non-linear regression of the effect of PUL and MF on the viability of PCLS and half-maximal effective concentration (EC50) calculation. Data represent the mean ± SD from PCLS of five liver samples (PUL) and two samples (MF) showing a significant viability decrease after the treatment. Full article ">Figure 4
Inter-individual variability in constitutive expression of selected miRNAs in PCLS from five patients. The horizontal line represents the median, and whiskers represent the maximum and minimum values. Full article ">Figure 5
The effect of PUL, MF and APAP on the normalized expression of selected miRNAs. The normalized expression level was calculated using the 2−ΔΔCt method with miR-93-5p as a reference gene. Results are presented as the mean ± SD. Statistical analyses were performed using one-way ANOVA with Dunnett’s test: p < 0.05 (*); p < 0.001 (**); p < 0.0001 (***). Full article ">Figure 5 Cont.
The effect of PUL, MF and APAP on the normalized expression of selected miRNAs. The normalized expression level was calculated using the 2−ΔΔCt method with miR-93-5p as a reference gene. Results are presented as the mean ± SD. Statistical analyses were performed using one-way ANOVA with Dunnett’s test: p < 0.05 (*); p < 0.001 (**); p < 0.0001 (***). Full article ">Figure 5 Cont.
The effect of PUL, MF and APAP on the normalized expression of selected miRNAs. The normalized expression level was calculated using the 2−ΔΔCt method with miR-93-5p as a reference gene. Results are presented as the mean ± SD. Statistical analyses were performed using one-way ANOVA with Dunnett’s test: p < 0.05 (*); p < 0.001 (**); p < 0.0001 (***). Full article ">

20 pages, 1415 KiB

Open AccessReview

The Type 3 Deiodinase: Epigenetic Control of Brain Thyroid Hormone Action and Neurological Function

by Arturo Hernandez and J. Patrizia Stohn

Int. J. Mol. Sci. 2018, 19(6), 1804; https://doi.org/10.3390/ijms19061804 - 19 Jun 2018

Cited by 31 | Viewed by 10189

Abstract

Thyroid hormones (THs) influence multiple processes in the developing and adult central nervous system, and their local availability needs to be maintained at levels that are tailored to the requirements of their biological targets. The local complement of TH transporters, deiodinase enzymes, and [...] Read more.

Thyroid hormones (THs) influence multiple processes in the developing and adult central nervous system, and their local availability needs to be maintained at levels that are tailored to the requirements of their biological targets. The local complement of TH transporters, deiodinase enzymes, and receptors is critical to ensure specific levels of TH action in neural cells. The type 3 iodothyronine deiodinase (DIO3) inactivates THs and is highly present in the developing and adult brain, where it limits their availability and action. DIO3 deficiency in mice results in a host of neurodevelopmental and behavioral abnormalities, demonstrating the deleterious effects of TH excess, and revealing the critical role of DIO3 in the regulation of TH action in the brain. The fact the Dio3 is an imprinted gene and that its allelic expression pattern varies across brain regions and during development introduces an additional level of control to deliver specific levels of hormone action in the central nervous system (CNS). The sensitive epigenetic nature of the mechanisms controlling the genomic imprinting of Dio3 renders brain TH action particularly susceptible to disruption due to exogenous treatments and environmental exposures, with potential implications for the etiology of human neurodevelopmental disorders. Full article

(This article belongs to the Special Issue Epigenetics of Neurodevelopmental Disorders)

► Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
Mechanisms of thyroid hormone action in the brain and its biological effects. DIO2 and DIO3, type 2, and type 3 deiodinase, respectively. T3, triiodothyroinine; T2, diiodothyronine; T4, thyroxine. Full article ">Figure 2
Neurological consequences of DIO3 deficiency in mice. The lack of DIO3 function prevents degradation of THs, increasing their availability and molecular action in the brain (red lines and arrows). Increased T3 action in the brain (grey arrow) leads to multiple neurological phenotypes (black arrows). TR, thyroid receptor; DIO2, type 2 deiodinase. Full article ">Figure 3
Genomic imprinting of Dio3 in the brain. (a) Simplified diagram of the mouse Dlk1-Dio3 imprinted domain showing the dominant pattern of allele-specific gene expression. An arbitrary number of pin point shapes indicate loci exhibiting allele-specific methylation (open circles, unmethylated; closed circles, methylated); (b) Brain variability in the percentage allelic contribution to Dio3 expression and associated IG-DMR methylation compared to fetal Dio3. Some brain regions exhibit relaxed or absent Dio3 imprinting despite unchanged IG-DMR methylation status [<a href="#B37-ijms-19-01804" class="html-bibr">37</a>]. (Data is approximate and based on parent-of-origin inheritance of the DIO3 mutation. Allelic contributions may add more than 100%, as the wild type allele may exhibit T3-dependent up-regulation upon loss of DIO3 function in the other allele). Full article ">Figure 4
Environmental factors and Dio3 imprinting. Environmental factors may influence Dio3 imprinting and expression, with consequences for TH action in the brain in affected (grey arrows) and future generations (dotted red arrow). Full article ">

14 pages, 1127 KiB

Open AccessReview

STAT3 in Tumor-Associated Myeloid Cells: Multitasking to Disrupt Immunity

by Yu-Lin Su, Shuvomoy Banerjee, Seok Voon White and Marcin Kortylewski

Int. J. Mol. Sci. 2018, 19(6), 1803; https://doi.org/10.3390/ijms19061803 - 19 Jun 2018

Cited by 81 | Viewed by 8335

Abstract

Myeloid immune cells, such as dendritic cells, monocytes, and macrophages, play a central role in the generation of immune responses and thus are often either disabled or even hijacked by tumors. These new tolerogenic activities of tumor-associated myeloid cells are controlled by an [...] Read more.

Myeloid immune cells, such as dendritic cells, monocytes, and macrophages, play a central role in the generation of immune responses and thus are often either disabled or even hijacked by tumors. These new tolerogenic activities of tumor-associated myeloid cells are controlled by an oncogenic transcription factor, signal transducer and activator of transcription 3 (STAT3). STAT3 multitasks to ensure tumors escape immune detection by impairing antigen presentation and reducing production of immunostimulatory molecules while augmenting the release of tolerogenic mediators, thereby reducing innate and adaptive antitumor immunity. Tumor-associated myeloid cells and STAT3 signaling in this compartment are now commonly recognized as an attractive cellular target for improving efficacy of standard therapies and immunotherapies. Hereby, we review the importance and functional complexity of STAT3 signaling in this immune cell compartment as well as potential strategies for cancer therapy. Full article

(This article belongs to the Special Issue Advances in Biological Functions of STAT3)

► Show Figures

Figure 1

17 pages, 2358 KiB

Open AccessArticle

Structure–Activity Relationship of Piplartine and Synthetic Analogues against Schistosoma mansoni and Cytotoxicity to Mammalian Cells

by Yuri Campelo, Alicia Ombredane, Andreanne G. Vasconcelos, Lucas Albuquerque, Daniel C. Moreira, Alexandra Plácido, Jefferson Rocha, Harold Hilarion Fokoue, Lydia Yamaguchi, Ana Mafud, Yvonne P. Mascarenhas, Cristina Delerue-Matos, Tatiana Borges, Graziella A. Joanitti, Daniel D.R. Arcanjo, Massuo J. Kato, Selma A. S. Kuckelhaus, Marcos P. N. Silva, Josué De Moraes and José Roberto S. A. Leite

Int. J. Mol. Sci. 2018, 19(6), 1802; https://doi.org/10.3390/ijms19061802 - 19 Jun 2018

Cited by 13 | Viewed by 4971

Abstract

Schistosomiasis, caused by helminth flatworms of the genus Schistosoma, is an infectious disease mainly associated with poverty that affects millions of people worldwide. Since treatment for this disease relies only on the use of praziquantel, there is an urgent need to identify [...] Read more.

Schistosomiasis, caused by helminth flatworms of the genus Schistosoma, is an infectious disease mainly associated with poverty that affects millions of people worldwide. Since treatment for this disease relies only on the use of praziquantel, there is an urgent need to identify new antischistosomal drugs. Piplartine is an amide alkaloid found in several Piper species (Piperaceae) that exhibits antischistosomal properties. The aim of this study was to evaluate the structure–function relationship between piplartine and its five synthetic analogues (19A, 1G, 1M, 14B and 6B) against Schistosoma mansoni adult worms, as well as its cytotoxicity to mammalian cells using murine fibroblast (NIH-3T3) and BALB/cN macrophage (J774A.1) cell lines. In addition, density functional theory calculations and in silico analysis were used to predict physicochemical and toxicity parameters. Bioassays revealed that piplartine is active against S. mansoni at low concentrations (5–10 µM), but its analogues did not. In contrast, based on 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry assays, piplartine exhibited toxicity in mammalian cells at 785 µM, while its analogues 19A and 6B did not reduce cell viability at the same concentrations. This study demonstrated that piplartine analogues showed less activity against S. mansoni but presented lower toxicity than piplartine. Full article

(This article belongs to the Section Biochemistry)

► Show Figures

Figure 1

Figure 1
Electron density: (a) piplartine; (b) 19A; (c) 1G; (d) 14B; (e) 6B and (f) 1M. The colours represent negative (red) and positive (blue). The dipole moments of all compounds in debye values are as follows: piplartine: 5.4728337; 1G: 1.9658996; 1M: 4.4568136; 6B: 4.0062111; 14B: 3.9403826; 19A: 3.7385640. Full article ">Figure 2
Ultraviolet and visible light absorption spectra of piplartine and its analogues in arbitrary units (A.U.). Full article ">Figure 3
Cytotoxicity evaluation using the MTT method in murine fibroblast (NIH3T3) cells after exposure for 24 h to piplartine analogues (A) 19A (72–2331 μM), (B) 6B (62–1998 μM), (C) 1G (85–2738 μM), (D) 1M (56–1796 μM), (E) 14B (101–3250 μM) and (F) piplartine (78–2514 μM). Molecules were used at the same concentrations range at μg/mL for all samples (25–800). Dimethyl sulfoxide (DMSO) was used as a negative control. The values are expressed as mean ± SEM. * p < 0.05 vs. DMSO control group. The dotted lines mark the 100% viability level. Full article ">Figure 4
Cytotoxicity evaluation in the mouse BALB/cN macrophage (J774A.1) cell line following exposure for 24 h to piplartine analogues (A) 19A (72, 291 and 1165 μM), (B) 6B (62, 249 and 999 μM), (C) 1G (85, 342 and 1369 μM), (D) 1M (56, 224 and 898 μM), (E) 14B (101, 406 and 1625 μM) and (F) piplartine (78, 314 and 1257 μM). Molecules were used at the same concentrations range at μg/mL for all samples (25, 100 and 400). Dulbecco’s Modified Eagle Medium (DMEM) was used as a negative control. Cells were analysed by flow cytometry (20,000 events/sample). The values are expressed as mean ± SEM. * p < 0.05 and **** p < 0.0001 vs. DMEM control group. Full article ">Figure 5
Evaluation of the cell death mechanism mediated by (A) piplartine (78, 314 and 1257 μM) and its analogues (B) 1G (85, 342 and 1369 μM), (C) 1M (56, 224 and 898 μM), (D) 6B (62, 249 and 999 μM), (E) 14B (101, 406 and 1625 μM) and (F) 19A (72, 291 and 1165 μM) in J774A.1 cells following treatment for 24 h at the same concentrations range at μg/mL for all samples (25, 100 and 400) using annexin-V FITC (apoptosis marker) and propidium iodide (PI, necrosis marker) staining. Cells were analysed by flow cytometry (20,000 events/sample). The values are expressed as mean ± SEM. * p < 0.05 vs. DMEM untreated control group. # p < 0.05 vs. apoptosis staining from each respective group. Full article ">

15 pages, 666 KiB

Open AccessReview

Role of Human Macrophage Polarization in Inflammation during Infectious Diseases

by Chiraz Atri, Fatma Z. Guerfali and Dhafer Laouini

Int. J. Mol. Sci. 2018, 19(6), 1801; https://doi.org/10.3390/ijms19061801 - 19 Jun 2018

Cited by 911 | Viewed by 35119

Abstract

Experimental models have often been at the origin of immunological paradigms such as the M1/M2 dichotomy following macrophage polarization. However, this clear dichotomy in animal models is not as obvious in humans, and the separating line between M1-like and M2-like macrophages is rather [...] Read more.

Experimental models have often been at the origin of immunological paradigms such as the M1/M2 dichotomy following macrophage polarization. However, this clear dichotomy in animal models is not as obvious in humans, and the separating line between M1-like and M2-like macrophages is rather represented by a continuum, where boundaries are still unclear. Indeed, human infectious diseases, are characterized by either a back and forth or often a mixed profile between the pro-inflammatory microenvironment (dominated by interleukin (IL)-1β, IL-6, IL-12, IL-23 and Tumor Necrosis Factor (TNF)-α cytokines) and tissue injury driven by classically activated macrophages (M1-like) and wound healing driven by alternatively activated macrophages (M2-like) in an anti-inflammatory environment (dominated by IL-10, Transforming growth factor (TGF)-β, chemokine ligand (CCL)1, CCL2, CCL17, CCL18, and CCL22). This review brews the complexity of the situation during infectious diseases by stressing on this continuum between M1-like and M2-like extremes. We first discuss the basic biology of macrophage polarization, function, and role in the inflammatory process and its resolution. Secondly, we discuss the relevance of the macrophage polarization continuum during infectious and neglected diseases, and the possibility to interfere with such activation states as a promising therapeutic strategy in the treatment of such diseases. Full article

(This article belongs to the Special Issue Macrophages in Inflammation)

► Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
Summary of the main macrophage polarization states of activated macrophages. Different stimuli and signaling pathways have been described as inducers of M1-like or M2-like activation states, of which the most widely referenced ones are summarized here. M1-like or M2-like polarization has been reported in humans as being related to distinct defensive or healing schemas. Many roles have been ascribed to these polarization status, of which pro- and anti-inflammatory macrophage potentiation has for a long time been classically associated to the M1-like/M2-like-like dichotomy. LPS: lipopolysaccharide; MR: mannose receptor; TNF: tumor necrosis factor; IFNg: interferon gamma; IL: interleukin; MCP: monocyte chemoattractant protein; TGF: transforming growth factor; MCSF: macrophage colony stimulating-factor; ROS: reactive oxygen species; iNOS: inducible nitric oxide synthase; MHC: major histocompatibility complex. Full article ">Figure 2
Macrophage polarization status observed in post-kala-azar dermal leishmaniasis (PKDL) patients during acute disease and after treatment. Leishmania infection in humans has been studied in PKDL patients, in which features of M2-like polarization have been observed in both lesion sites and peripheral blood. M2-like polarization is characterized by the increased mRNA and/or protein expression of specific M2-like markers such as the nuclear peroxisome proliferator activated receptor γ (PPARγ), the arginase-1 receptor, and the membrane mannose receptor CD206/mannose receptor (MR). After treatment, disease resolution is characterized by an M1-like profile repolarization, evidenced by the decreased expression of M2-like markers. Full article ">

15 pages, 2793 KiB

Open AccessArticle

MK-0677, a Ghrelin Agonist, Alleviates Amyloid Beta-Related Pathology in 5XFAD Mice, an Animal Model of Alzheimer’s Disease

by Yu-on Jeong, Soo Jung Shin, Jun Yong Park, Bo Kyeong Ku, Ji Soo Song, Jwa-Jin Kim, Seong Gak Jeon, Sang Min Lee and Minho Moon

Int. J. Mol. Sci. 2018, 19(6), 1800; https://doi.org/10.3390/ijms19061800 - 18 Jun 2018

Cited by 30 | Viewed by 10402

Abstract

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by cognitive deficits, neuroinflammation, and neuronal death. The primary pathogenic cause is believed to be the accumulation of pathogenic amyloid beta (Aβ) assemblies in the brain. Ghrelin, which is a peptide hormone predominantly secreted [...] Read more.

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by cognitive deficits, neuroinflammation, and neuronal death. The primary pathogenic cause is believed to be the accumulation of pathogenic amyloid beta (Aβ) assemblies in the brain. Ghrelin, which is a peptide hormone predominantly secreted from the stomach, is an endogenous ligand for the growth hormone secretagogue-receptor type 1a (GHS-R1a). MK-0677 is a ghrelin agonist that potently stimulates the GHS-R1a ghrelin receptor. Interestingly, previous studies have shown that ghrelin improves cognitive impairments and attenuates neuronal death and neuroinflammation in several neurological disorders. However, it is unknown whether MK-0677 can affect Aβ accumulation or Aβ-mediated pathology in the brains of patients with AD. Therefore, we examined the effects of MK-0677 administration on AD-related pathology in 5XFAD mice, an Aβ-overexpressing transgenic mouse model of AD. MK-0677 was intraperitoneally administered to three-month-old 5XFAD mice. To visualize Aβ accumulation, neuroinflammation, and neurodegeneration, thioflavin-S staining and immunostaining with antibodies against Aβ (4G8), ionized calcium-binding adaptor molecule 1 (Iba-1), glial fibrillary acidic protein (GFAP), neuronal nuclear antigen (NeuN), and synaptophysin were conducted in the neocortex of 5XFAD and wild-type mice, and to evaluate changes of phosphorylated cyclic adenosine monophosphate (cAMP) response element binding protein (pCREB) levels, immunostaining with antibody against pCREB was performed in dentate gyrus of the hippocampus of 5XFAD and wild-type mice. The histological analyses indicated that MK-0677-treated 5XFAD mice showed reduced Aβ deposition, gliosis, and neuronal and synaptic loss in the deep cortical layers, and inhibited the decrement of pCREB levels in dentate gyrus of the hippocampus compared to vehicle-treated 5XFAD mice. Our results showed that activation of the ghrelin receptor with MK-0677 inhibited the Aβ burden, neuroinflammation, and neurodegeneration, which suggested that MK-0677 might have potential as a treatment of the early phase of AD. Full article

(This article belongs to the Special Issue Amyloid Fibrils and Methods for Their Study)

► Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
Cumulative food intake and change in body weight after the administration of MK-0677 in C57BL/6 mice and 5XFAD mice. MK-0677 was administered daily to C57BL/6 mice (n = 5) at doses of 0.1, 1, and 3 mg/kg for 10 days and to 5XFAD mice at doses of 5 mg/kg for three weeks. The group injected with MK-0677 exhibited a significant increase in cumulative food intake compared with the control group. Compared with the control group, the significant difference indicators are as follows: 0.1 mg/kg group († p < 0.05), 1 mg/kg group (‡ p < 0.001), and 3 mg/kg group (* p < 0.05 and ** p < 0.01) (A). The body weight changes for 10 days were also significantly increased in the group receiving MK-0677 (** p < 0.01 and *** p < 0.001 indicate significant differences compared to control group) (B). MK-0677-treated 5XFAD mice (n = 8) showed tendency to the increase of cumulative food intake induced compared with vehicle-treated 5XFAD mice (n = 8) (C). The body weight changes among wild-type mice (n = 8), vehicle- and, MK-0677-treated 5XFAD mice were not significantly different (D). Full article ">Figure 2
MK-0677 treatment significantly reduced Aβ plaques in the deep cortical layers of 5XFAD mice. The burden of Aβ was estimated by thoflavin-S staining and immunohistochemical staining for the 4G8 antibody. 5XFAD mice treated with MK-0677 (n = 6) showed a decreased positive area (%) in both thioflavin-S (A) and 4G8 (B)-stained brains, compared with vehicle-treated 5XFAD mice (n = 7). *** p < 0.001 indicates significant differences between the groups. Scale bar = 50 μm. Full article ">Figure 3
MK-0677-treated 5XFAD mice exhibited a significant reduction in neurodegeneration compared with the vehicle group. Immunofluorescent staining was performed to detect the markers of neuronal cells (NeuN) and pre-synaptic terminals (SYN) in layer V of the frontal cortex of wild-type (n = 8) and 5XFAD mice. MK-0677 significantly ameliorated the reduction of the number of NeuN (+) cells (A) and optical density of SYN (+) area (B) in 5XFAD mice (n = 6), compared with vehicle-treated 5XFAD mice (n = 7). *** p < 0.001 indicates significant differences between the groups. Scale bars are 50 μm in the upper panel and 25 μm in the lower panel. Full article ">Figure 4
MK-0677-treated 5XFAD mice exhibited significant inhibition of neuroinflammation compared with vehicle-administered mice. Immunofluorescent staining was performed to detect the markers of microglia (Iba-1) and astrocyte (GFAP) in layer V of the frontal cortex of wild-type (n = 8) and 5XFAD mice. MK-0677 significantly reduced the Iba-1 (+) area (A) and GFAP (+) area (B) in 5XFAD mice (n = 6), compared with vehicle-treated 5XFAD mice (n = 7). *** p < 0.001 indicates significant differences between the groups. Scale bar = 50 μm. Full article ">Figure 5
MK-0677 treatment significantly improved the reduced phosphorylation of CREB in 5XFAD mice. Immunofluorescent staining was performed to detect the phosphorylation form of CREB (pCREB) in dentate gyrus of the hippocampus of wild-type (n = 8) and 5XFAD mice. MK-0677-treated 5XFAD mice (n = 6) showed significantly increased pCREB, compared with vehicle-treated 5XFAD mice (n = 7). * p < 0.05 and *** p < 0.001 indicate significant differences between the groups. Scale bar = 50 μm. CREB = cyclic adenosine monophosphate (cAMP) response element binding protein. Full article ">

16 pages, 4737 KiB

Open AccessArticle

STIM1 Knockout Enhances PDGF-Mediated Ca²⁺ Signaling through Upregulation of the PDGFR–PLCγ–STIM2 Cascade

by Tzu-Yu Huang, Yi-Hsin Lin, Heng-Ai Chang, Tzu-Ying Yeh, Ya-Han Chang, Yi-Fan Chen, Ying-Chi Chen, Chun-Chun Li and Wen-Tai Chiu

Int. J. Mol. Sci. 2018, 19(6), 1799; https://doi.org/10.3390/ijms19061799 - 18 Jun 2018

Cited by 11 | Viewed by 5074

Abstract

Platelet-derived growth factor (PDGF) has mitogenic and chemotactic effects on fibroblasts. An increase in intracellular Ca²⁺ is one of the first events that occurs following the stimulation of PDGF receptors (PDGFRs). PDGF activates Ca²⁺ elevation by activating the phospholipase C gamma [...] Read more.

Platelet-derived growth factor (PDGF) has mitogenic and chemotactic effects on fibroblasts. An increase in intracellular Ca²⁺ is one of the first events that occurs following the stimulation of PDGF receptors (PDGFRs). PDGF activates Ca²⁺ elevation by activating the phospholipase C gamma (PLCγ)-signaling pathway, resulting in ER Ca²⁺ release. Store-operated Ca²⁺ entry (SOCE) is the major form of extracellular Ca²⁺ influx following depletion of ER Ca²⁺ stores and stromal interaction molecule 1 (STIM1) is a key molecule in the regulation of SOCE. In this study, wild-type and STIM1 knockout mouse embryonic fibroblasts (MEF) cells were used to investigate the role of STIM1 in PDGF-induced Ca²⁺ oscillation and its functions in MEF cells. The unexpected findings suggest that STIM1 knockout enhances PDGFR–PLCγ–STIM2 signaling, which in turn increases PDGF-BB-induced Ca²⁺ elevation. Enhanced expressions of PDGFRs and PLCγ in STIM1 knockout cells induce Ca²⁺ release from the ER store through PLCγ–IP3 signaling. Moreover, STIM2 replaces STIM1 to act as the major ER Ca²⁺ sensor in activating SOCE. However, activation of PDGFRs also activate Akt, ERK, and JNK to regulate cellular functions, such as cell migration. These results suggest that alternative switchable pathways can be observed in cells, which act downstream of the growth factors that regulate Ca²⁺ signaling. Full article

(This article belongs to the Special Issue Calcium Signaling in Human Health and Diseases)

► Show Figures

Graphical abstract

18 pages, 3795 KiB

Open AccessArticle

Regulation and Function of TMEM16F in Renal Podocytes

by Laura K. Schenk, Jiraporn Ousingsawat, Boris V. Skryabin, Rainer Schreiber, Hermann Pavenstädt and Karl Kunzelmann

Int. J. Mol. Sci. 2018, 19(6), 1798; https://doi.org/10.3390/ijms19061798 - 18 Jun 2018

Cited by 5 | Viewed by 4983

Abstract

The Ca²⁺-activated phospholipid scramblase and ion channel TMEM16F is expressed in podocytes of renal glomeruli. Podocytes are specialized cells that form interdigitating foot processes as an essential component of the glomerular filter. These cells, which participate in generation of the primary [...] Read more.

The Ca²⁺-activated phospholipid scramblase and ion channel TMEM16F is expressed in podocytes of renal glomeruli. Podocytes are specialized cells that form interdigitating foot processes as an essential component of the glomerular filter. These cells, which participate in generation of the primary urine, are often affected during primary glomerular diseases, such as glomerulonephritis and secondary hypertensive or diabetic nephropathy, which always leads to proteinuria. Because the function of podocytes is known to be controlled by intracellular Ca²⁺ signaling, it is important to know about the role of Ca²⁺-activated TMEM16F in these cells. To that end, we generated an inducible TMEM16F knockdown in the podocyte cell line AB8, and produced a conditional mouse model with knockout of TMEM16F in podocytes and renal epithelial cells of the nephron. We found that knockdown of TMEM16F did not produce proteinuria or any obvious phenotypic changes. Knockdown of TMEM16F affected cell death of tubular epithelial cells but not of glomerular podocytes when analyzed in TUNEL assays. Surprisingly, and in contrast to other cell types, TMEM16F did not control intracellular Ca²⁺ signaling and was not responsible for Ca²⁺-activated whole cell currents in podocytes. TMEM16F levels in podocytes were enhanced after inhibition of the endolysosomal pathway and after treatment with angiotensin II. Renal knockout of TMEM16F did not compromise renal morphology and serum electrolytes. Taken together, in contrast to other cell types, such as platelets, bone cells, and immune cells, TMEM16F shows little effect on basal properties of podocytes and does not appear to be essential for renal function. Full article

(This article belongs to the Special Issue Ion Transporters and Channels in Physiology and Pathophysiology)

► Show Figures

Figure 1

29 pages, 5040 KiB

Open AccessReview

Role of MicroRNAs in Renal Parenchymal Diseases—A New Dimension

by Saeed Kamran Shaffi, David Galas, Alton Etheridge and Christos Argyropoulos

Int. J. Mol. Sci. 2018, 19(6), 1797; https://doi.org/10.3390/ijms19061797 - 17 Jun 2018

Cited by 22 | Viewed by 5148

Abstract

Since their discovery in 1993, numerous microRNAs (miRNAs) have been identified in humans and other eukaryotic organisms, and their role as key regulators of gene expression is still being elucidated. It is now known that miRNAs not only play a central role in [...] Read more.

Since their discovery in 1993, numerous microRNAs (miRNAs) have been identified in humans and other eukaryotic organisms, and their role as key regulators of gene expression is still being elucidated. It is now known that miRNAs not only play a central role in the processes that ensure normal development and physiology, but they are often dysregulated in various diseases. In this review, we present an overview of the role of miRNAs in normal renal development and physiology, in maladaptive renal repair after injury, and in the pathogenesis of renal parenchymal diseases. In addition, we describe methods used for their detection and their potential as therapeutic targets. Continued research on renal miRNAs will undoubtedly improve our understanding of diseases affecting the kidneys and may also lead to new therapeutic agents. Full article

(This article belongs to the Special Issue The Role of MicroRNAs in Human Diseases)

► Show Figures

Figure 1

26 pages, 37748 KiB

Open AccessReview

Bioengineering Approaches for Bladder Regeneration

by Ángel Serrano-Aroca, César David Vera-Donoso and Victoria Moreno-Manzano

Int. J. Mol. Sci. 2018, 19(6), 1796; https://doi.org/10.3390/ijms19061796 - 17 Jun 2018

Cited by 64 | Viewed by 10438

Abstract

Current clinical strategies for bladder reconstruction or substitution are associated to serious problems. Therefore, new alternative approaches are becoming more and more necessary. The purpose of this work is to review the state of the art of the current bioengineering advances and obstacles [...] Read more.

Current clinical strategies for bladder reconstruction or substitution are associated to serious problems. Therefore, new alternative approaches are becoming more and more necessary. The purpose of this work is to review the state of the art of the current bioengineering advances and obstacles reported in bladder regeneration. Tissue bladder engineering requires an ideal engineered bladder scaffold composed of a biocompatible material suitable to sustain the mechanical forces necessary for bladder filling and emptying. In addition, an engineered bladder needs to reconstruct a compliant muscular wall and a highly specialized urothelium, well-orchestrated under control of autonomic and sensory innervations. Bioreactors play a very important role allowing cell growth and specialization into a tissue-engineered vascular construct within a physiological environment. Bioprinting technology is rapidly progressing, achieving the generation of custom-made structural supports using an increasing number of different polymers as ink with a high capacity of reproducibility. Although many promising results have been achieved, few of them have been tested with clinical success. This lack of satisfactory applications is a good reason to discourage researchers in this field and explains, somehow, the limited high-impact scientific production in this area during the last decade, emphasizing that still much more progress is required before bioengineered bladders become a commonplace in the clinical setting. Full article

(This article belongs to the Special Issue Cell Colonization in Scaffolds)

► Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
Urinary bladder histological organization in physiological conditions. (I–IV) Representative images of a longitudinal bladder section from an adult male rat after trichromic Masson staining. The adventitious layer (the outermost one), the urothelium (II), and the muscle bundles (IV) are stained in dark red, and the extracellular matrix of the submucosa is stained in blue (III). The location of the layers II, III, and IV is shown in image I by a corresponding colored frame with a dashed line; V: The illustration on the right shows the bladder organization in layers. Starting from the lumen, the bladder is composed of a transitional epithelium or urothelium formed by 4–5 layers of specialized cells supported by the basal lamina and followed by the submucosa coat, a loose connective tissue containing fibroblasts, blood vessels, and extracellular matrix and enriched in collagen I and III. Below, consecutive layers with perpendicular orientations of smooth muscle fibers form an inner muscle layer followed by the detrusor, characterized by smooth muscle fibers organized in circular and longitudinal layers. The adventitious layer of adipose tissue completes the structural organization. Full article ">Figure 2
Types of urinary diversion currently performed after radical cystectomy: (a) abdominal diversion, such as an ureterocutaneostomy, colonic, or ileal conduit; (b) various forms of a continent pouch created using different segments of the gastrointestinal system and a cutaneous stoma; and (c) orthotopic urinary diversion with an intestinal segment with spherical configuration and anastomosis to the urethra (neobladder, orthotopic bladder substitution). Full article ">Figure 3
Acellular bladder submucosa scaffolds. Scanning electron micrographs (SEM) of fresh bladder submucosa (BSM) at 1000× magnification: surface (a) and cross section (b,c). The scale bar indicates 200 µm. Reprinted with permission from Elsevier Ltd., Liu et al. [<a href="#B58-ijms-19-01796" class="html-bibr">58</a>]. Full article ">Figure 4
Morphology of a poly(ε-caprolactone (PCL)/poly-l-lactide (PLLA) scaffold and cell distribution by SEM. Non-woven and randomly oriented fibers of PCL and PLLA at 500× (A) and 5000× (B) magnifications; (C) Urothelial cells on the scaffold surface preserving their phenotype by creating their typical colonies; (D) Bladder smooth muscle cells expanded and proliferated on the scaffold. Reprinted with permission from Elsevier Ltd., Shakhssalim et al. [<a href="#B47-ijms-19-01796" class="html-bibr">47</a>]. Full article ">Figure 5
In vitro bioreactor: a computer senses the pressure in pressure chamber (B) by feedback via a pressure transducer (E). A computer interface establishes and maintains a specific hydrodynamic pressure by controlling a pump (A) output. A pressure valve (C) is almost completely closed to simulate bladder outlet obstruction. Dulbecco’s modified Eagle’s medium with 10% fetal bovine serum was used. The arrows indicate the flow direction. (D) Fluid reservoir. Reprinted with permission from Elsevier Ltd., Chen et al. [<a href="#B50-ijms-19-01796" class="html-bibr">50</a>]. Full article ">Figure 6
In vivo bioreactor: seeded scaffold preparation (A–C) and implantation (D) in the omentum. Reprinted with permission from Elsevier Ltd., Baumert et al. [<a href="#B147-ijms-19-01796" class="html-bibr">147</a>]. Full article ">Figure 7
Bioprinting technologies: components of laser-induced forward transfer (a), inkjet printing (b) and robotic dispensing (c). Adapted from John Wiley and Sons, Malda et al. [<a href="#B163-ijms-19-01796" class="html-bibr">163</a>]. Full article ">

38 pages, 4933 KiB

Open AccessReview

Shining Light on Chitosan: A Review on the Usage of Chitosan for Photonics and Nanomaterials Research

by Sreekar B. Marpu and Erin N. Benton

Int. J. Mol. Sci. 2018, 19(6), 1795; https://doi.org/10.3390/ijms19061795 - 17 Jun 2018

Cited by 54 | Viewed by 8660

Abstract

Chitosan (CS) is a natural polymer derived from chitin that has found its usage both in research and commercial applications due to its unique solubility and chemical and biological attributes. The biocompatibility and biodegradability of CS have helped researchers identify its utility in [...] Read more.

Chitosan (CS) is a natural polymer derived from chitin that has found its usage both in research and commercial applications due to its unique solubility and chemical and biological attributes. The biocompatibility and biodegradability of CS have helped researchers identify its utility in the delivery of therapeutic agents, tissue engineering, wound healing, and more. Industrial applications include cosmetic and personal care products, wastewater treatment, and corrosion protection, to name a few. Many researchers have published numerous reviews outlining the physical and chemical properties of CS, as well as its use for many of the above-mentioned applications. Recently, the cationic polyelectrolyte nature of CS was found to be advantageous for stabilizing fascinating photonic materials including plasmonic nanoparticles (e.g., gold and silver), semiconductor nanoparticles (e.g., zinc oxide, cadmium sulfide), fluorescent organic dyes (e.g., fluorescein isothiocyanate (FITC)), luminescent transitional and lanthanide complexes (e.g., Au(I) and Ru(II), and Eu(III)). These photonic systems have been extensively investigated for their usage in antimicrobial, wound healing, diagnostics, sensing, and imaging applications. Highlighted in this review are the different works involving some of the above-mentioned molecular-nano systems that are prepared or stabilized using the CS polymer. The advantages and the role of the CS for synthesizing and stabilizing the above-mentioned optically active materials have been illustrated. Full article

(This article belongs to the Special Issue Chitins 2018)

► Show Figures

Graphical abstract

13 pages, 1639 KiB

Open AccessReview

Scorpins in the DNA Damage Response

by Dario Palmieri, Anna Tessari and Vincenzo Coppola

Int. J. Mol. Sci. 2018, 19(6), 1794; https://doi.org/10.3390/ijms19061794 - 17 Jun 2018

Cited by 10 | Viewed by 5074

Abstract

The DNA Damage Response (DDR) is a complex signaling network that comes into play when cells experience genotoxic stress. Upon DNA damage, cellular signaling pathways are rewired to slow down cell cycle progression and allow recovery. However, when the damage is beyond repair, [...] Read more.

The DNA Damage Response (DDR) is a complex signaling network that comes into play when cells experience genotoxic stress. Upon DNA damage, cellular signaling pathways are rewired to slow down cell cycle progression and allow recovery. However, when the damage is beyond repair, cells activate complex and still not fully understood mechanisms, leading to a complete proliferative arrest or cell death. Several conventional and novel anti-neoplastic treatments rely on causing DNA damage or on the inhibition of the DDR in cancer cells. However, the identification of molecular determinants directing cancer cells toward recovery or death upon DNA damage is still far from complete, and it is object of intense investigation. SPRY-containing RAN binding Proteins (Scorpins) RANBP9 and RANBP10 are evolutionarily conserved and ubiquitously expressed proteins whose biological functions are still debated. RANBP9 has been previously implicated in cell proliferation, survival, apoptosis and migration. Recent studies also showed that RANBP9 is involved in the Ataxia Telangiectasia Mutated (ATM) signaling upon DNA damage. Accordingly, cells lacking RANBP9 show increased sensitivity to genotoxic treatment. Although there is no published evidence, extensive protein similarities suggest that RANBP10 might have partially overlapping functions with RANBP9. Like RANBP9, RANBP10 bears sites putative target of PIK-kinases and high throughput studies found RANBP10 to be phosphorylated following genotoxic stress. Therefore, this second Scorpin might be another overlooked player of the DDR alone or in combination with RANBP9. This review focuses on the relatively unknown role played by RANBP9 and RANBP10 in responding to genotoxic stress. Full article

(This article belongs to the Special Issue Alterations to Signalling Pathways in Cancer Cells 2018)

► Show Figures

Figure 1

Figure 1
Schematic representation of RANBP9 and RANBP10 proteins. RANBP10 shares high amino acid conservation with RANBP9 in the PRY (94%), SPRY (97%), LisH (82%), CTLH (90%), and CRA (89%) domains. The two proteins differ the most at the N-terminus and in the post-CTLH region, which contains several putative PIK-kinase phosphorylation sites (see <a href="#ijms-19-01794-t001" class="html-table">Table 1</a>). PRD (red)= Proline-Rich Domain; PRY/SPRY (light blue) = Spore lysis A and Ryanodine receptor Domain; LisH (green) = Lissencephaly type-I-like homology motif; CTLH (yellow) = Carboxy-terminal to LisH motif domain; CRA (orange) = CT11-RanBP9 domain; dark blue = putative Nuclear Localization Signal; Tub (purple) = tubulin-binding domain. Full article ">Figure 2
Schematic representation of the S. cerevisiae Glucose-Induced degradation Deficient (GID)- and correspondent mammalian CTLH-macromolecular complexes. (A) The topology of the GID complex in yeast is well established [<a href="#B31-ijms-19-01794" class="html-bibr">31</a>]; (B) Predicted composition of the mammalian CTLH complex based on the GID mammalian homologs. The name of the complex comes from the CTLH domain that most of the members have; (C) CTLH or Nuclear Receptor coregulator-complex pulled down from mammalian cells including RANBP9 and RANBP10 (adapted from [<a href="#B29-ijms-19-01794" class="html-bibr">29</a>]). In the depicted complex, GID8 is named C20orf11 and indicated as C20. The experiment showed as part of the complex also YPEL5 (Yippee Like 5) indicated as Y5 in the cartoon, which has no known equivalent in the S. cerevisiae GID complex. Full article ">Figure 3
Potential action mechanism of RANBP9 in ATM-dependent DDR. In RANBP9 (red) expressing cells and in the absence of DNA damage (left panel, top), RANBP9 protein shuttles between the nucleus and the cytoplasm. Upon DNA damage such as IR and DNA-damaging drugs (left panel, bottom), ATM is activated and enhances RANBP9 nuclear accumulation through its phosphorylation, potentially with other cytoplasmic partners (purple). This event potentially leads to enhanced KAT5-dependent ATM acetylation, a marker of its full activation. For this reason, RANBP9-expressing cells activate an efficient ATM signaling pathway, resulting in efficient DNA repair and survival to genotoxic stress. Conversely, when RANBP9 expression is reduced, the full activation of ATM is impaired, leading to inefficient DNA repair and sensitivity to DNA damaging agents. Full article ">

14 pages, 1022 KiB

Open AccessReview

Epigenomic Control of Thermogenic Adipocyte Differentiation and Function

by Xu Peng, Qiongyi Zhang, Cheng Liao, Weiping Han and Feng Xu

Int. J. Mol. Sci. 2018, 19(6), 1793; https://doi.org/10.3390/ijms19061793 - 17 Jun 2018

Cited by 14 | Viewed by 5844

Abstract

Obesity and its associated metabolic disorders are spreading at a fast pace throughout the world; thus, effective therapeutic approaches are necessary to combat this epidemic. Obesity develops when there is a greater caloric intake than energy expenditure. Promoting energy expenditure has recently attracted [...] Read more.

Obesity and its associated metabolic disorders are spreading at a fast pace throughout the world; thus, effective therapeutic approaches are necessary to combat this epidemic. Obesity develops when there is a greater caloric intake than energy expenditure. Promoting energy expenditure has recently attracted much attention as a promising approach for the management of body weight. Thermogenic adipocytes are capable of burning fat to dissipate chemical energy into heat, thereby enhancing energy expenditure. After the recent re-discovery of thermogenic adipocytes in adult humans, much effort has focused on understanding the molecular mechanisms, especially the epigenetic mechanisms, which regulate thermogenic adipocyte development and function. A number of chromatin signatures, such as histone modifications, DNA methylation, chromatin accessibilities, and interactions, have been profiled at the genome level and analyzed in various murine and human thermogenic fat cell systems. Moreover, writers and erasers, as well as readers of the epigenome are also investigated using genomic tools in thermogenic adipocytes. In this review, we summarize and discuss the recent advance in these studies and highlight the insights gained into the epigenomic regulation of thermogenic program as well as the pathogenesis of human metabolic diseases. Full article

(This article belongs to the Special Issue Transcriptional Regulation in Lipid Metabolism)

► Show Figures

Graphical abstract

16 pages, 1644 KiB

Open AccessReview

The Expensive-Tissue Hypothesis in Vertebrates: Gut Microbiota Effect, a Review

by Chun Hua Huang, Xin Yu and Wen Bo Liao

Int. J. Mol. Sci. 2018, 19(6), 1792; https://doi.org/10.3390/ijms19061792 - 17 Jun 2018

Cited by 22 | Viewed by 8838

Abstract

The gut microbiota is integral to an organism’s digestive structure and has been shown to play an important role in producing substrates for gluconeogenesis and energy production, vasodilator, and gut motility. Numerous studies have demonstrated that variation in diet types is associated with [...] Read more.

The gut microbiota is integral to an organism’s digestive structure and has been shown to play an important role in producing substrates for gluconeogenesis and energy production, vasodilator, and gut motility. Numerous studies have demonstrated that variation in diet types is associated with the abundance and diversity of the gut microbiota, a relationship that plays a significant role in nutrient absorption and affects gut size. The Expensive-Tissue Hypothesis states (ETH) that the metabolic requirement of relatively large brains is offset by a corresponding reduction of the other tissues, such as gut size. However, how the trade-off between gut size and brain size in vertebrates is associated with the gut microbiota through metabolic requirements still remains unexplored. Here, we review research relating to and discuss the potential influence of gut microbiota on the ETH. Full article

(This article belongs to the Special Issue The (Microbiota)–Gut–Brain Axis: Hype or Revolution?)

► Show Figures

Figure 1

Figure 1
Regulation of food intake via gut-brain pathway. (A) When undigested dietary residue arrives at the caecum, colon, rumen, and hind gut, the bacteria populated in the intestines ferment them to short-chain fatty acids (SCFAs) (e.g., acetate, propionate, and butyrate). Then free fatty acid receptor 2 (FFAR2) and free fatty acid receptor 3 (FFAR3) on the L-cells interact with SCFAs to trigger the secretion of anorectic hormones, including peptide YY (PYY) and glucagon-like peptide 1 (GLP1). PYY and GLP1 then preferentially bind to the Y2 receptor located on the arcuate nucleus of the hypothalamus via the vagus nerve, which further increases the expression of the anorexigenic pro-opiomelanocortin (POMC) neuropeptide while decreasing the expression of neuropeptide Y (NPY), thus managing to control food intake; (B) Microbiota ferment dietary nutrients, digesting them to SCFAs. Acetate molecules then stimulate the vagus nerve, which triggers the stomach to secrete the “hunger hormone” ghrelin, leading to the increase of food intake. Full article ">Figure 2
SCFAs in liver circulation and central metabolism. Butyrate, propionate, and acetate enter the liver via the portal vein after passing through the mesenteric veins, cecal veins, and colonic veins. They are then utilized for lipogenesis and gluconeogenesis in the liver, the products of which then enter blood circulation. SCFAs are an important source of energy (in the form of ATP) for colonocytes and for gluconeogenesis in the modulation of the central metabolism. Full article ">Figure 3
The Relationship Between Gut and Brain Size. Full article ">

Journal Menu

Journal Browser

Int. J. Mol. Sci., Volume 19, Issue 6 (June 2018) – 276 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI