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Search Results (1,262)

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12 pages, 2705 KiB  
Article
3D-Cultured MC3T3-E1-Derived Exosomes Promote Endothelial Cell Biological Function under the Effect of LIPUS
by Xiaohan Liu, Rui Cheng, Hongjuan Cao and Lin Wu
Biomolecules 2024, 14(9), 1154; https://doi.org/10.3390/biom14091154 - 13 Sep 2024
Viewed by 238
Abstract
Porous Ti-6Al-4V scaffold materials can be used to heal massive bone defects because they can provide space for vascularisation and bone formation. During new bone tissue development, rapid vascular ingrowth into scaffold materials is very important. Osteoblast-derived exosomes are capable of facilitating angiogenesis–osteogenesis [...] Read more.
Porous Ti-6Al-4V scaffold materials can be used to heal massive bone defects because they can provide space for vascularisation and bone formation. During new bone tissue development, rapid vascular ingrowth into scaffold materials is very important. Osteoblast-derived exosomes are capable of facilitating angiogenesis–osteogenesis coupling. Low-intensity pulsed ultrasound (LIPUS) is a physical therapy modality widely utilised in the field of bone regeneration and has been proven to enhance the production and functionality of exosomes on two-dimensional surfaces. The impact of LIPUS on exosomes derived from osteoblasts cultured in three dimensions remains to be elucidated. In this study, exosomes produced by osteoblasts on porous Ti-6Al-4V scaffold materials under LIPUS and non-ultrasound stimulated conditions were co-cultured with endothelial cells. The findings indicated that the exosomes were consistently and stably taken up by the endothelial cells. Compared to the non-ultrasound group, the LIPUS group facilitated endothelial cell proliferation and angiogenesis. After 24 h of co-culture, the migration ability of endothelial cells in the LIPUS group was 17.30% higher relative to the non-ultrasound group. LIPUS may represent a potentially viable strategy to promote the efficacy of osteoblast-derived exosomes to enhance the angiogenesis of porous Ti-6Al-4V scaffold materials. Full article
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<p>Isolation and identification of exosomes. The separated exosomes were characterised by scanning electron microscopy, nanoparticle tracking analysis (NTA), and identification of surface marker proteins. (<b>A</b>) Methodology for ultrasonic loading of cells and extraction and identification of exosomes. (<b>B</b>) SEM images of MC3T3-E1 were grown within the porous Ti-6Al-4V scaffold. (<b>C</b>) Morphology of exosomes under electron microscopy, scale bar = 200 nm. (<b>D</b>) Particle size distribution and concentration in the exosome suspension, with the size of particles in both LIPUS and control groups ranging between 30 and 300 nm, consistent with known exosomal dimensions. (<b>E</b>) Expression of HSP70, TSG101, and calreticulin in exosomes from each group. Western blot original images can be found in <a href="#app1-biomolecules-14-01154" class="html-app">Supplementary Materials</a>. (<b>F</b>) Measurement of exosome concentration in three independent experiments showed no significant difference between the LIPUS and control groups. ns: <span class="html-italic">p</span> ˃ 0.05.</p>
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<p>Endothelial cells took up Dil-labelled exosomes. After co-culturing with pre-stained exosomes for 24 h, red fluorescence signals could be observed inside both LIPUS and control group HUVEC cells, with no significant difference in fluorescence signal intensity between the two groups.</p>
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<p>Exosomes extracted from MC3T3-E1 cells stimulated by ultrasound better promote endothelial cell migration. (<b>A</b>) Schematic of functional experiments. (<b>B</b>) CCK8 assay to assess endothelial cell proliferation. (<b>C</b>) Transwell assay to assess exosome-promoted endothelial cell migration ability, scale bar = 100 μm. (<b>D</b>) Statistical analysis results of endothelial cell migration. One-way analysis of variance was used for testing, and pairwise comparisons were conducted using a post hoc LSD test, n = 3, *: <span class="html-italic">p</span> &lt; 0.05, **: <span class="html-italic">p</span> &lt; 0.01, ***: <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>Endothelial cell tube formation experiment. (<b>A</b>) Under microscopic observation, scale bar = 100 um. (<b>B</b>) Image J was used for statistical analysis of the tube formation experiment results: (a) total tube length, (b) number of nodes, (c) number of junctions, (d) number of branches. One-way analysis of variance was used for testing, and pairwise comparisons were conducted using a post hoc LSD test, n = 3, *: <span class="html-italic">p</span> &lt; 0.05, **: <span class="html-italic">p</span> &lt; 0.01, ***: <span class="html-italic">p</span> &lt; 0.001.</p>
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13 pages, 1611 KiB  
Review
Endochondral Ossification for Spinal Fusion: A Novel Perspective from Biological Mechanisms to Clinical Applications
by Rile Ge, Chenjun Liu, Yuhong Zhao, Kaifeng Wang and Xiluan Wang
J. Pers. Med. 2024, 14(9), 957; https://doi.org/10.3390/jpm14090957 - 9 Sep 2024
Viewed by 238
Abstract
Degenerative scoliosis (DS), encompassing conditions like spondylolisthesis and spinal stenosis, is a common type of spinal deformity. Lumbar interbody fusion (LIF) stands as a conventional surgical intervention for this ailment, aiming at decompression, restoration of intervertebral height, and stabilization of motion segments. Despite [...] Read more.
Degenerative scoliosis (DS), encompassing conditions like spondylolisthesis and spinal stenosis, is a common type of spinal deformity. Lumbar interbody fusion (LIF) stands as a conventional surgical intervention for this ailment, aiming at decompression, restoration of intervertebral height, and stabilization of motion segments. Despite its widespread use, the precise mechanism underlying spinal fusion remains elusive. In this review, our focus lies on endochondral ossification for spinal fusion, a process involving vertebral development and bone healing. Endochondral ossification is the key step for the successful vertebral fusion. Endochondral ossification can persist in hypoxic conditions and promote the parallel development of angiogenesis and osteogenesis, which corresponds to the fusion process of new bone formation in the hypoxic region between the vertebrae. The ideal material for interbody fusion cages should have the following characteristics: (1) Good biocompatibility; (2) Stable chemical properties; (3) Biomechanical properties similar to bone tissue; (4) Promotion of bone fusion; (5) Favorable for imaging observation; (6) Biodegradability. Utilizing cartilage-derived bone-like constructs holds promise in promoting bony fusion post-operation, thus warranting exploration in the context of spinal fusion procedures. Full article
(This article belongs to the Section Mechanisms of Diseases)
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<p>Intramembranous ossification and endochondral ossification.</p>
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<p>The mechanisms for bone repair in the spine.</p>
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<p>Four main types of materials for interbody fusion cages.</p>
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10 pages, 3158 KiB  
Article
Role of Pulsed Electromagnetic Field on Alveolar Bone Remodeling during Orthodontic Retention Phase in Rat Models
by Hafiedz Maulana, Yuyun Yueniwati, Nur Permatasari and Hadi Suyono
Dent. J. 2024, 12(9), 287; https://doi.org/10.3390/dj12090287 - 9 Sep 2024
Viewed by 262
Abstract
Alveolar bone remodeling during the retention phase is essential for successful orthodontic treatment. Pulsed electromagnetic field (PEMF) therapy is an adjunctive therapy for bone-related diseases that induces osteogenesis and prevents bone loss. This study aimed to examine the role of PEMF exposure during [...] Read more.
Alveolar bone remodeling during the retention phase is essential for successful orthodontic treatment. Pulsed electromagnetic field (PEMF) therapy is an adjunctive therapy for bone-related diseases that induces osteogenesis and prevents bone loss. This study aimed to examine the role of PEMF exposure during the retention phase of orthodontic treatment in alveolar bone remodeling. A total of 36 male Wistar rats were divided into control, PEMF 7, and PEMF 14 groups; a 50 g force nickel–titanium closed-coil spring was inserted to create mesial movement in the first molar for 21 d. Furthermore, the spring was removed, and the interdental space was filled with glass ionomer cement. Concurrently, rats were exposed to a PEMF at 15 Hz with a maximum intensity of 2.0 mT 2 h daily, for 7 and 14 days. Afterwards, the cements were removed and the rats were euthanized on days 1, 3, 7, and 14 to evaluate the expression of Wnt5a mRNA and the levels of RANKL, OPG, ALP, and Runx2 on the tension side. The data were analyzed with ANOVA and post hoc tests, with p < 0.05 declared statistically significant. PEMF exposure significantly upregulated Wnt5a mRNA expression, OPG and ALP levels, and Runx2 expression, and decreased RANKL levels in the PEMF 7 and 14 groups compared to the control group (p < 0.05). This study showed that PEMF exposure promotes alveolar bone remodeling during the orthodontic retention phase on the tension side by increasing alveolar bone formation and inhibiting resorption. Full article
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<p>Research design. (<b>A</b>) PEMF stimulation phases, (<b>B</b>) orthodontic appliance installation, (<b>C</b>) post orthodontic tooth movement, (<b>D</b>) absorption of GCF sample with paper points, and (<b>E</b>) sampling region (white arrow) for RT-PCR. PEMF: pulsed electromagnetic field, GCF: gingival crevicular fluid, RT-PCR: real-time polymerase chain reaction.</p>
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<p>PEMF stimulator. (<b>A</b>) The PEMF device and rats were kept in a special fiber cage, placed between a Helmholtz coil and exposed 2 h/day. (<b>B</b>) The waveform was square with a burst width of 5 ms, burst wait of 60 ms, pulse width of 0.2 ms, pulse wait of 0.02 ms, pulse rise of 0.3 μs, and pulse fall of 2.0 μs.</p>
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<p>The histogram of Wnt5a mRNA expression. *: <span class="html-italic">p</span> &lt; 0.05, significant compared with control group. PEMF: pulsed electromagnetic field.</p>
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<p>The histogram of RANKL, OPG, and ALP levels. *: <span class="html-italic">p</span> &lt; 0.05, significant compared with control group; #: <span class="html-italic">p</span> &lt; 0.05, significant compared with PEMF 7 group. PEMF: pulsed electromagnetic field, RANKL: receptor activator of nuclear factor-kappa B ligand, OPG: osteoprotegerin, ALP: alkaline phosphatase.</p>
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<p>Histogram and immunohistochemical image of Runx2 expression. Runx2 positive-osteoblast (black arrow) and the direction of tooth movement (blue arrow). *: <span class="html-italic">p</span> &lt; 0.05, significant compared with control group; #: <span class="html-italic">p</span> &lt; 0.05, significant compared with PEMF 7 group. PEMF: pulsed electromagnetic field, T: tooth, PDL: periodontal ligament, AB: alveolar bone, Runx2: runt-related transcription factor 2.</p>
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17 pages, 7749 KiB  
Article
Decoding Cold Therapy Mechanisms of Enhanced Bone Repair through Sensory Receptors and Molecular Pathways
by Matthew Zakaria, Justin Matta, Yazan Honjol, Drew Schupbach, Fackson Mwale, Edward Harvey and Geraldine Merle
Biomedicines 2024, 12(9), 2045; https://doi.org/10.3390/biomedicines12092045 - 9 Sep 2024
Viewed by 345
Abstract
Applying cold to a bone injury can aid healing, though its mechanisms are complex. This study investigates how cold therapy impacts bone repair to optimize healing. Cold was applied to a rodent bone model, with the physiological responses analyzed. Vasoconstriction was mediated by [...] Read more.
Applying cold to a bone injury can aid healing, though its mechanisms are complex. This study investigates how cold therapy impacts bone repair to optimize healing. Cold was applied to a rodent bone model, with the physiological responses analyzed. Vasoconstriction was mediated by an increase in the transient receptor protein channels (TRPs), transient receptor potential ankyrin 1 (TRPA1; p = 0.012), and transient receptor potential melastatin 8 (TRPM8; p < 0.001), within cortical defects, enhancing the sensory response and blood flow regulation. Cold exposure also elevated hypoxia (p < 0.01) and vascular endothelial growth factor expression (VEGF; p < 0.001), promoting angiogenesis, vital for bone regeneration. The increased expression of osteogenic proteins peroxisome proliferator-activated receptor gamma coactivator (PGC-1α; p = 0.039) and RNA-binding motif protein 3 (RBM3; p < 0.008) suggests that the reparative processes have been stimulated. Enhanced osteoblast differentiation and the presence of alkaline phosphatase (ALP) at day 5 (three-fold, p = 0.021) and 10 (two-fold, p < 0.001) were observed, along with increased osteocalcin (OCN) at day 10 (two-fold, p = 0.019), indicating the presence of mature osteoblasts capable of mineralization. These findings highlight cold therapy’s multifaceted effects on bone repair, offering insights for therapeutic strategies. Full article
(This article belongs to the Section Cell Biology and Pathology)
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<p>Potential mechanisms activated in response to cold exposure.</p>
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<p>Identification of receptor proteins involved in vasoconstriction within a cortical defect following cold exposure. TRPM8 and TRPA1 detection (bright green) within the cortical defect region (4× magnification). Scale bar represents 500 µm. (<b>A</b>,<b>D</b>) are non-treated femurs serving as a baseline. (<b>B</b>,<b>E</b>) are cold-treated femurs. (<b>C</b>) TRPA1 staining expression analysis (<span class="html-italic">n</span> = 8) of positive staining for TRPA1 in the control group was 5.38 ± 2.32, while in the experimental group it was 9.03% ± 2.78 (* <span class="html-italic">p</span>-value = 0.012). (<b>F</b>) TRPM8 staining expression analysis (<span class="html-italic">n</span> = 8) of positive staining for TRPM8 in the control group was 3.86% ± 1.72, while in the experimental group it was 8.75% ± 1.68 (** <span class="html-italic">p</span>-value &lt; 0.001).</p>
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<p>Identification of angiogenic-related factors and endothelial cells within a cortical defect following cold exposure. VEGF and CD34 (bright green) detection within the cortical defect region (4× magnification). Scale bar represents 500 µm. (<b>A</b>,<b>D</b>,<b>G</b>) are the cold-treated femurs. (<b>B</b>,<b>E</b>,<b>H</b>) are the non-treated femurs serving as a baseline. (<b>C</b>) Hypoxia staining expression analysis (<span class="html-italic">n</span> = 10) of positive staining for hypoxia in the control group was 17.9% ± 3.8, while in the experimental group it was 23.5% ± 05.8 (* <span class="html-italic">p</span>-value &lt; 0.01). (<b>F</b>) VEGF staining expression analysis (<span class="html-italic">n</span> = 8) of positive staining for VEGF in the control group was 4.05% ± 1.83, while in the experimental group it was 9.69% ± 1.75 (* <span class="html-italic">p</span>-value &lt; 0.001). (<b>I</b>) CD34 staining expression analysis (<span class="html-italic">n</span> = 8) of positive staining for CD34 in the control group was 6.92% ± 2.77, while in the experimental group it was 8.00% ± 2.76 (<span class="html-italic">p</span>-value = 0.42).</p>
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<p>Identification of cold-shock proteins and hypoxia in regenerating bone following cold exposure. PGC-1a (brown), RBM3 (brown), and hypoxia (brown) detection within the cortical defect region (4x magnification). Scale bar represents 500 µm. (<b>A</b>,<b>D</b>) are cold-treated femurs. (<b>B</b>,<b>E</b>) are non-treated femurs serving as a baseline. (<b>C</b>) RBM3 staining expression analysis (<span class="html-italic">n</span> = 8) of positive staining for RBM3 in the control group was 4.47% ± 2.84, while in the experimental group it was 11.0% ± 4.26 (** <span class="html-italic">p</span>-value &lt; 0.008). (<b>F</b>) PGC-1a staining expression analysis (<span class="html-italic">n</span> = 8) of positive staining for PGC-1a in the control group was 2.57% ± 0.36, while in the experimental group it was 5.85% ± 1.01 (* <span class="html-italic">p</span>-value = 0.039).</p>
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<p>Prevalence of PGC-1a at the junction of old and new bone formation following cold therapy treatment. (<b>A</b>,<b>E</b>) at 2.5× magnification. Scale bar represents 500 µm. (<b>B</b>–<b>D</b>,<b>F</b>–<b>H</b>) at 20× magnification. Scale bar represents 50 µm. PGC-1a has been shown to be upregulated (<b>I</b>) at the junction of new and old bone. (<b>F</b>–<b>H</b>) Furthermore, PGC-1a expression within these junctions appears to be elevated following cold exposure (<b>B</b>–<b>D</b>) indicating PGC-1a upregulation. (<b>I</b>) Detected location of PGC-1α staining expression analysis (<span class="html-italic">n</span> = 8) of PGC-1α within cells at the junction of newly formed bone and old bone was 70.56% ± 7.08, while in non-junctional regions it was 29.44% ± 7.08 (* <span class="html-italic">p</span>-value &lt; 0.00001).</p>
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<p>Detection of ALP and OCN at day 5 and day 10 within isolated osteoblasts following cold exposure and mineralization within isolate osteoblasts following cold exposure for 14 days. (<b>A</b>) ALP activity after 5 days of cold exposure was 2.72 U/L (µmol/min/L) ± 0.85, while in the non-treated group it was 0.74 U/L ± 0.35 (* <span class="html-italic">p</span>-value = 0.021). (<b>B</b>) ALP activity after 10 days of cold exposure was 2.25 U/L ± 0.04, while in the non-treated group it was 1.0301 U/L ± 0.24 (** <span class="html-italic">p</span>-value &lt; 0.001). (<b>C</b>) OCN levels after 5 days of cold exposure was 0.34 mg/mL ± 0.10, while in the non-treated group it was 0.43 mg/mL ± 0.10 (<span class="html-italic">p</span>-value = 0.29). (<b>D</b>) OCN levels after 10 days of cold exposure was 0.84 mg/mL ± 0.17, while in the non-treated group it was 0.35 mg/mL ± 0.10 (*** <span class="html-italic">p</span>-value = 0.019). ARS (red) detection within isolated osteoblasts (10× magnification). Scale bar represents 250 µm. (<b>E</b>) Osteoblasts isolated from non-treated fractured femurs. (<b>F</b>) Osteoblasts isolated from daily cold-treated fractured femurs. (<b>G</b>) ARS staining analysis: Detection of ARS after 14 days of cold exposure was 1.04% ± 0.40, while in the non-treated group it was 0.27% ± 0.025 (*** <span class="html-italic">p</span>-value = 0.030).</p>
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<p>Cold-based activation of vasoconstrictive pathways and hypoxic impact. (<b>A</b>,<b>B</b>) TRPA1 and TRPM8 cold exposure mechanism leads to the activation of TRPM8 (8–28 °C) and TRPA1 (8–17 °C), initiating a contractive response leading to vasoconstriction. (<b>C</b>) Hypoxic impacts. A reduction in the influx of blood supply coincides with a decrease in oxygen availability, leading to the formation of an acute hypoxic microenvironment with respect to nearby cells. NA: norepinephrine.</p>
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<p>Hypoxic upregulation following vasoconstriction via local cold exposure and the impact on angiogenic pathways. Under normal oxygen conditions, HIF-1a is degraded via von Hippel–Lindau (VHL) disease after prolyl hydroxylation, but in hypoxia, HIF-1a forms a dimer with HIF-1B, nucleolocalizes with the aryl hydrocarbon receptor nuclear translocator (ARNT), leading to VEGF expression through the HRE pathway, which then activates VEGFR2 in endothelial cells, upregulating cellular proliferation and angiogenesis via the Ras/Raf signaling pathway.</p>
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<p>Cellular adaptive signaling pathways activated by cold exposure. RBM3 activation and downstream osteogenic potential following short-term cold exposure. (<b>A</b>) Cold exposure triggers a cellular cold-shock response, activating RBM3 via HSPs released by phosphorylated and nuclear-localized HSF1. (<b>B</b>) HSP70 activates TLR4, initiating the MyD88/NF-kB pathway, with phosphorylated NF-kB essential for RBM3 expression. (<b>C</b>) RBM3 activates the MAPK/ERK pathway, leading to Runx2 and osteocalcin (OCN) expression, crucial for osteoblast differentiation. PGC-1a activation and downstream osteogenic potential following short-term cold exposure. PGC-1α activation and osteogenic potential following short-term cold exposure. (<b>D</b>) Cold activation of adrenergic receptors and TRPs stimulates cAMP and calcium influx, leading to CREB phosphorylation via the PKA/Ca<sup>2+</sup>/CaMK pathway. (<b>E</b>) PGC-1α forms a complex with ERRα in osteoblastic cells, promoting differentiation via the Runx2/OCN pathway for mineralization. (<b>F</b>) PGC-1α and NRF-1/NRF-2 activate TFAM and NCMP, crucial for mitochondrial biogenesis and intracellular calcium storage.</p>
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<p>Overview of the mechanistic propensities of short-duration cold exposure and the potential impacts on a bone injury site. Blue: Observed impact of cold exposure on bone and vasculature morphology. Green: Observed impact of cold exposure on pathways involved in bone repair.</p>
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16 pages, 1250 KiB  
Article
Assessing the Muscle–Bone Unit in Girls Exposed to Different Amounts of Impact-Loading Physical Activity—A Cross-Sectional Association Study
by Valentina Cavedon, Marco Sandri, Carlo Zancanaro and Chiara Milanese
Children 2024, 11(9), 1099; https://doi.org/10.3390/children11091099 - 7 Sep 2024
Viewed by 431
Abstract
Background/Objectives: In children, an association exists between muscle and bone, as well as between physical activity and osteogenesis. Impact loading is a factor in increasing bone accrual during growth. In this work, we explored the muscle–bone association in girls exposed to long-term physical [...] Read more.
Background/Objectives: In children, an association exists between muscle and bone, as well as between physical activity and osteogenesis. Impact loading is a factor in increasing bone accrual during growth. In this work, we explored the muscle–bone association in girls exposed to long-term physical activity at different levels of impact loading. Methods: Four groups of girls aged 7–16 were considered. The curricular (C; n = 22) group only had curricular physical activity at school (2 h/w). In addition to curricular physical activity, the girls in the dance (D; n = 21), gymnastics at lower training (GL; n = 14), and gymnastics at higher training (GH; n = 20) groups had 2 h/w, 4 h/w, and 4 h/w < training ≤ 12 h/w additional physical activity, respectively, for at least one year. A visual analysis estimated the respective amounts of impact-loading activity. The bone mineral content (BMC), areal bone mineral density (aBMD), and fat-free soft tissue mass (FFSTM) were assessed with dual-energy X-ray absorptiometry. Results: The results showed that, after adjusting for several confounders, statistically significant correlations were present between muscle mass and several bone mineral variables. A regression analysis confirmed the correlation in the data, and showed the marginal role of other body composition variables and physical activity for predicting BMC and BMD. Conclusion: Skeletal muscle mass is a major determinant of the BMC and BMD of the TBLH, as well as of the Appendicular level, in girls exposed to different amounts of long-term impact-loading physical activity. Full article
(This article belongs to the Section Pediatric Orthopedics & Sports Medicine)
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<p>Association (Pearson’s r) between fat-free soft tissue mass (FFSTM) and bone mineral content (BMC) at four sites.</p>
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<p>Association (Pearson’s r) between fat-free soft tissue mass (FFSTM) and areal bone mineral content (aBMD) at four sites.</p>
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<p>Representative example of variable importance estimated by random forests for predicting lumbar spine aBMD. Only variable(s) with confidence intervals not intersecting zero line were selected for regression analysis. For abbreviations, see text. Append., Appendicular.</p>
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15 pages, 2821 KiB  
Article
Comparing the Immune Response to PEEK as an Implant Material with and without P-15 Peptide as Bone Graft Material in a Rabbit Long Bone Model
by Boyle C. Cheng, Isaac R. Swink, Cooper T. Cheng, Owen G. Corcoran, Vicki Z. Wang, Edward J. McClain, Praveer S. Vyas, Izzy Owen, Chen Xu, Daniel T. Altman and Alexander K. Yu
Bioengineering 2024, 11(9), 898; https://doi.org/10.3390/bioengineering11090898 - 6 Sep 2024
Viewed by 530
Abstract
P-15 is a 15-amino-acid-long biomimetic peptide widely demonstrated to enhance osteogenesis in vivo. Despite the prevalence of polyether-ether-ketone (PEEK) in interbody device manufacturing, a growing body of evidence suggests it may produce an unfavorable immune response. The purpose of this preliminary study was [...] Read more.
P-15 is a 15-amino-acid-long biomimetic peptide widely demonstrated to enhance osteogenesis in vivo. Despite the prevalence of polyether-ether-ketone (PEEK) in interbody device manufacturing, a growing body of evidence suggests it may produce an unfavorable immune response. The purpose of this preliminary study was to characterize the immune response and new bone growth surrounding PEEK implants with and without a P-15 peptide-based osteobiologic. A bilateral femoral defect model was conducted using New Zealand white rabbits. A total of 17 test subjects received one implant in each distal femur, either with or without bone graft material. Animals were allowed to survive to 4 or 8 weeks, at which time the femurs were collected and subjected to micro-computer tomography (microCT) or cytokine analysis. MicroCT analysis included the quantification of bone growth and density surrounding each implant. The cytokine analysis of periprosthetic tissue homogenates included the quantification of interleukins (ILs) and TNF-α expression via ELISA kits. Improvements in bone volume were observed in the P-15 cohort for the regions of interest, 500–136 and 136–0 µm from the implant surface, at 8 weeks post-op. Concentrations of IL-1β, IL-4, and IL-6 cytokines were significantly higher in the P-15 cohort compared to the PEEK cohort at the 4-week timepoint. Significant reductions in the concentrations of IL-4 and IL-6 cytokines from the 4- to 8-week cohort were observed in the P-15 cohort only. The P-15 peptide has the potential to modulate the immune response to implanted materials. We observed improvements in bone growth and a more active micro-environment in the P-15 cohort relative to the PEEK control. This may indicate an earlier transition from the inflammatory to remodeling phase of healing. Full article
(This article belongs to the Section Biomedical Engineering and Biomaterials)
11 pages, 1388 KiB  
Article
Clinical, Radiographic, and Biomechanical Evaluation of the Upper Extremity in Patients with Osteogenesis Imperfecta
by Katharina Oder, Fabian Unglaube, Sebastian Farr, Andreas Kranzl, Alexandra Stauffer, Rudolf Ganger, Adalbert Raimann and Gabriel T. Mindler
J. Clin. Med. 2024, 13(17), 5174; https://doi.org/10.3390/jcm13175174 - 31 Aug 2024
Viewed by 443
Abstract
Introduction: Osteogenesis imperfecta (OI) is a hereditary disorder primarily caused by mutations in type I collagen genes, resulting in bone fragility, deformities, and functional limitations. Studies on upper extremity deformities and associated functional impairments in OI are limited. This cross-sectional study aimed to [...] Read more.
Introduction: Osteogenesis imperfecta (OI) is a hereditary disorder primarily caused by mutations in type I collagen genes, resulting in bone fragility, deformities, and functional limitations. Studies on upper extremity deformities and associated functional impairments in OI are limited. This cross-sectional study aimed to evaluate upper extremity deformities and functional outcomes in OI. Methods: We included patients regardless of their OI subtypes with a minimum age of 7 years. Radiographic analysis of radial head dislocation, ossification of the interosseous membrane, and/or radioulnar synostosis of the forearm were performed, and deformity was categorized as mild, moderate, or severe. Clinical evaluation was performed using the Quick Disabilities of Arm, Shoulder, and Hand (qDASH) questionnaire and shoulder-elbow-wrist range of motion (ROM). Three-dimensional motion analysis of the upper limb was conducted using the Southampton Hand Assessment Procedure (SHAP). The SHAP quantifies execution time through the Linear Index of Function (LIF) and assesses the underlying joint kinematics using the Arm Profile Score (APS). Additionally, the maximum active Range of Motion (aRoM) was measured. Results: Fourteen patients aged 8 to 73 were included. Radiographic findings revealed diverse deformities, including radial head dislocation, interosseous membrane ossification, and radioulnar synostosis. Six patients had mild, six moderate, and two severe deformities of the upper extremity. Severe deformities and radial head dislocation correlated with compromised ROM and worse qDASH scores. The qDASH score ranged from 0 to 37.5 (mean 11.7). APS was increased, and LIF was reduced in OI-affected persons compared with non-affected peers. APS and LIF also varied depending on the severity of bony deformities. aRoM was remarkably reduced for pro-supination. Conclusion: Patients with OI showed variable functional impairment from almost none to severe during daily life activities, mainly depending on the magnitude of deformity in the upper extremity. Larger multicenter studies are needed to confirm the results of this heterogeneous cohort. Level of evidence: Retrospective clinical study; Level IV. Full article
(This article belongs to the Special Issue Challenges in Hand and Upper Limb Surgery)
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<p>APS in relation to the underlying bony deformities. Gray: mean of non-affected persons with one and two times standard deviation; *: mean; -: median; small box: one times standard deviation; wide box: interquartile range; n: number of extremities; mean ± standard deviation.</p>
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<p>LIF in relation to the underlying bony deformities. Gray: mean of non-affected persons with one and two times standard deviation; *: mean; -: median; small box: one times standard deviation; wide box: interquartile range; n: number of extremities; mean ± standard deviation.</p>
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<p>Pro-supination aRoM in relation to the bony deformities. Gray: mean of non-affected persons with one and two times standard deviation; *: mean; -: median; small box: one times standard deviation; wide box: interquartile range; n: number of extremities; mean ± standard deviation.</p>
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<p>Differences between OI-affected and non-affected persons for all SHAP tasks. The black bars indicate tasks that require more forearm supination/pronation.</p>
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15 pages, 1247 KiB  
Systematic Review
The Effectiveness of Curcumin Nanoparticle-Coated Titanium Surfaces in Osteogenesis: A Systematic Review
by Nandita Suresh, Matti Mauramo, Tuomas Waltimo, Timo Sorsa and Sukumaran Anil
J. Funct. Biomater. 2024, 15(9), 247; https://doi.org/10.3390/jfb15090247 - 27 Aug 2024
Viewed by 575
Abstract
(1) Background: This systematic review critically appraises and synthesizes evidence from in vitro studies investigating the effects of curcumin nanoparticles on titanium surface modification, focusing on cell adhesion, proliferation, osteogenic differentiation, and mineralization. (2) Methods: A comprehensive electronic search was conducted in PubMed, [...] Read more.
(1) Background: This systematic review critically appraises and synthesizes evidence from in vitro studies investigating the effects of curcumin nanoparticles on titanium surface modification, focusing on cell adhesion, proliferation, osteogenic differentiation, and mineralization. (2) Methods: A comprehensive electronic search was conducted in PubMed, Cochrane Central Register of Controlled Trials, and Google Scholar databases, yielding six in vitro studies that met the inclusion criteria. The search strategy and study selection process followed PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A qualitative methodological assessment was performed using the SciRAP (Science in Risk Assessment and Policy) method, which evaluated the reporting and methodological quality of the included studies. (3) Results: All six studies consistently demonstrated that curcumin-coated titanium surfaces inhibited osteoclastogenesis and promoted osteogenic activity, evidenced by enhanced cell adhesion, proliferation, osteogenic differentiation, and mineralization. The mean reporting quality score was 91.8 (SD = 5.7), and the mean methodological quality score was 85.8 (SD = 10.50), as assessed by the SciRAP method. Half of the studies used hydroxyapatite-coated titanium as a control, while the other half used uncoated titanium, introducing potential variability in baseline comparisons. (4) Conclusions: This systematic review provides compelling in vitro evidence supporting the osteogenic potential of curcumin nanoparticle-coated titanium surfaces. The findings suggest that this surface modification strategy may enhance titanium implants’ biocompatibility and osteogenic properties, potentially improving dental and orthopedic implant outcomes. However, the review highlights significant heterogeneity in experimental designs and a concentration of studies from a single research group. Further research, particularly in vivo studies and clinical trials from diverse research teams, is essential to validate these findings and comprehensively understand the translational potential of this promising surface modification approach. Full article
(This article belongs to the Section Synthesis of Biomaterials via Advanced Technologies)
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Figure 1
<p>Schematic representation of a curcumin-enhanced titanium implant coating experiment. The diagram illustrates the potential influence of the coated implant on various cellular processes relevant to bone regeneration and implant integration. Ti64 alloy is coated with curcumin (CUR) and hydroxyapatite (HA) using various coating methods. Cell culture dish containing multiple cell types (THP1, MG-63, hFOB, BMSCs, NIH3T3, and MC3T3-E1). Hypothesized effects on different cell types, including osteoblasts, osteoclasts, immune cells, MG-63, and hFOB cells, as indicated by arrows.</p>
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<p>PRISMA flow diagram of the study selection process.</p>
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15 pages, 22217 KiB  
Article
Effects of Scutellaria baicalensis Extract-Induced Exosomes on the Periodontal Stem Cells and Immune Cells under Fine Dust
by Mihae Yun and Boyong Kim
Nanomaterials 2024, 14(17), 1396; https://doi.org/10.3390/nano14171396 - 27 Aug 2024
Viewed by 418
Abstract
In adverse environments, fine dust is linked to a variety of health disorders, including cancers, cardiovascular, neurological, renal, reproductive, motor, systemic, and respiratory diseases. Although PM10 is associated with oral inflammation and cancer, there is limited research on biomaterials that prevent damage caused [...] Read more.
In adverse environments, fine dust is linked to a variety of health disorders, including cancers, cardiovascular, neurological, renal, reproductive, motor, systemic, and respiratory diseases. Although PM10 is associated with oral inflammation and cancer, there is limited research on biomaterials that prevent damage caused by fine dust. In this study, we evaluated the effects of biomaterials using microRNA profiling, flow cytometry, conventional PCR, immunocytochemistry, Alizarin O staining, and ELISA. Compared to SBE (Scutellaria baicalensis extract), the preventive effectiveness of SBEIEs (SBE-induced exosomes) against fine dust was approximately two times higher. Furthermore, SBEIEs promoted cellular differentiation of periodontal ligament stem cells (PDLSCs) into osteoblasts, periodontal ligament cells (PDLCs), and pulp progenitor cells (PPCs), enhancing immune modulation for oral health against fine dust. In terms of immune modulation, SBEIEs activated the secretion of cytokines such as IL-10, LL-37, and TGF-β in T cells, B cells, and macrophages, while attenuating the secretion of MCP-1 in macrophages. MicroRNA profiling revealed that significantly modulated miRNAs in SBEIEs influenced four biochemical categories: apoptosis, cellular differentiation, immune activation, and anti-inflammation. These findings suggest that SBEIEs are an optimal biomaterial for developing oral health care products. Additionally, this study proposes functional microRNA candidates for the development of pharmaceutical liposomes. Full article
(This article belongs to the Special Issue Nanosomes in Precision Nanomedicine (Second Edition))
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<p>Establishment of treatment dosages for gingival cells and PDLSCs. Cellular viability of SBE (<b>a</b>,<b>b</b>), fine dust (PM10) (<b>c</b>), and exosomes from gingival cells under various conditions; control-induced exosomes (<b>d</b>), SBE-induced exosomes (<b>e</b>), and PM10-induced exosomes (<b>f</b>) using flow cytometry; ns: not significant (* <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001).</p>
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<p>Profiling of microRNAs in induced exosomes from gingival cells. Radar charts for alteration of miRNAs in induced exosomes. CIE: control-induced exosomes; PM10IE: PM10-induced exosomes; SBEIE: SBE-induced exosomes; <span class="html-italic">p</span> &lt; 0.05.</p>
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<p>Differentiation of PDLSCs under conditioned media. Patterns of differentiation from PDLSCs under the conditioned media (con, PM10CM, SBECM, and SBECM + PM10). Con: control; PM10CM: supernatant from gingival cells under PM10; SBECM: supernatant from gingival cells under SBE; SBECM + PM10: supernatant from gingival cells sequential exposed to under SBECM and PM10; PDLC: periodontal ligament cells; PPC: pulp progenitor cells; ns: not significant (* <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001).</p>
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<p>Differentiation of PDLSCs under induced exosomes. Patterns of differentiation from PDLSCs under the conditioned media (CE, PM10IE, SBEIE, and SBEIE + PM10). CE: control-induced exosomes; PM10IE: PM10-induced exosomes; SBEIE: SBE-induced exosomes; SBEIE + PM10: sequential exposure under SBEIE and PM10; PDLC: periodontal ligament cells; PPC: pulp progenitor cells (* <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001).</p>
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<p>PDLC differentiation from PDLSCs under induced exosomes. Images for differentiated PDLCs using immunocytochemistry. Asporin-expressed cells show as green. Differentiation from PDLSCs under the conditioned media (CE, PM10IE, SBEIE, and SBEIE + PM10). CE: control-induced exosomes; PM10IE: PM10-induced exosomes; SBEIE: SBE-induced exosomes; SBEIE + PM10: sequential exposure under SBEIE and PM10; PDLC: periodontal ligament cells; PPC: pulp progenitor cells; ns: not significant; scale bars 10 μm (* <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001).</p>
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<p>Osteogenic differentiation from PDLSCs under induced exosomes. Levels of osteogenic markers under induced exosomes (<b>a</b>). Results of Alizarin O stain for differentiated cells under induced exosomes and the bar graph display the relative folds for cell counts (<b>b</b>). ns: not significant; scale bars 10 μm (* <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001).</p>
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<p>Phagocytic activation of macrophages under induced exosomes. Phagocytic activation of macrophages for bacteria (<b>a</b>) and FITC labelled viral peptides (<b>b</b>) under induced exosomes (* <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001).</p>
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<p>Enhancement of periodontal health by induced exosomes. Expression of IL-10 in B and T cells, TGF-β in T cells, and LL-37 and MCP-1 in macrophages under induced exosomes. The levels of cytokines evaluate using ELISA. ns: not significant (* <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001).</p>
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22 pages, 2500 KiB  
Article
Role of Oxidative Stress Signaling, Nrf2, on Survival and Stemness of Human Adipose-Derived Stem Cells Exposed to X-rays, Protons and Carbon Ions
by Mira Hammad, Rima Salma, Jacques Balosso, Mohi Rezvani and Siamak Haghdoost
Antioxidants 2024, 13(9), 1035; https://doi.org/10.3390/antiox13091035 - 26 Aug 2024
Viewed by 475
Abstract
Some cancers have a poor prognosis and often lead to local recurrence because they are resistant to available treatments, e.g., glioblastoma. Attempts have been made to increase the sensitivity of resistant tumors by targeting pathways involved in the resistance and combining it, for [...] Read more.
Some cancers have a poor prognosis and often lead to local recurrence because they are resistant to available treatments, e.g., glioblastoma. Attempts have been made to increase the sensitivity of resistant tumors by targeting pathways involved in the resistance and combining it, for example, with radiotherapy (RT). We have previously reported that treating glioblastoma stem cells with an Nrf2 inhibitor increases their radiosensitivity. Unfortunately, the application of drugs can also affect normal cells. In the present study, we aim to investigate the role of the Nrf2 pathway in the survival and differentiation of normal human adipose-derived stem cells (ADSCs) exposed to radiation. We treated ADSCs with an Nrf2 inhibitor and then exposed them to X-rays, protons or carbon ions. All three radiation qualities are used to treat cancer. The survival and differentiation abilities of the surviving ADSCs were studied. We found that the enhancing effect of Nrf2 inhibition on cell survival levels was radiation-quality-dependent (X-rays > proton > carbon ions). Furthermore, our results indicate that Nrf2 inhibition reduces stem cell differentiation by 35% and 28% for adipogenesis and osteogenesis, respectively, using all applied radiation qualities. Interestingly, the results show that the cells that survive proton and carbon ion irradiations have an increased ability, compared with X-rays, to differentiate into osteogenesis and adipogenesis lineages. Therefore, we can conclude that the use of carbon ions or protons can affect the stemness of irradiated ADSCs at lower levels than X-rays and is thus more beneficial for long-time cancer survivors, such as pediatric patients. Full article
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<p>Experimental setup to study the effect of Nrf2i and radiation quality on the survival of ADSCs.</p>
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<p>Quantitative analysis of HO-1 (<b>A</b>) and NQO1 (<b>B</b>) proteins by Western blot in ADSC, 5 days after treatment with Nrf2i. A paired <span class="html-italic">t</span>-test was performed. The values are presented as mean ± standard deviation, <span class="html-italic">n</span> = 6, *; <span class="html-italic">p</span> &lt; 0.05, **; <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>Quantitative analysis of HO-1 (<b>A</b>) and NQO1 (<b>B</b>) proteins by Western blot in ADSC, 5 days after treatment with Nrf2i. A paired <span class="html-italic">t</span>-test was performed. The values are presented as mean ± standard deviation, <span class="html-italic">n</span> = 6, *; <span class="html-italic">p</span> &lt; 0.05, **; <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>Dose–response relationships of survival of adipose-derived stem cells (ADSCs) in the absence (<b>A</b>) and presence (<b>B</b>) of Nrf2i (ML385) in response to different radiation qualities. The survivals were established by staining cells with trypan blue dye and counting viable cells. The values are presented by mean ± standard deviation, <span class="html-italic">n</span> = 3, **; <span class="html-italic">p</span> &lt; 0.001, ***; <span class="html-italic">p</span> &lt; 0.0001.</p>
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<p>Ratio of mature adipocytes to undifferentiated ADSCs in the absence (●) and presence of Nrf2i (■) exposed to different radiation qualities: X-rays (<b>A</b>), protons (<b>B</b>) and carbon ions (<b>C</b>). The values are presented as mean ± standard deviation, <span class="html-italic">n</span> = 3, *; <span class="html-italic">p</span> &lt; 0.05, **; <span class="html-italic">p</span> &lt; 0.001, ***; <span class="html-italic">p</span> &lt; 0.0001.</p>
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<p>Ratio of mature adipocytes to undifferentiated ADSCs in the absence (●) and presence of Nrf2i (■) exposed to different radiation qualities: X-rays (<b>A</b>), protons (<b>B</b>) and carbon ions (<b>C</b>). The values are presented as mean ± standard deviation, <span class="html-italic">n</span> = 3, *; <span class="html-italic">p</span> &lt; 0.05, **; <span class="html-italic">p</span> &lt; 0.001, ***; <span class="html-italic">p</span> &lt; 0.0001.</p>
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<p>The effects of radiation quality and Nrf2i on osteogenesis. Normalized optical densities at 405 nm after alizarin red staining in the absence (●) and presence of Nrf2i (■) after different radiation qualities X-rays (<b>A</b>), protons (<b>B</b>) and carbon ions (<b>C</b>). The values are presented by mean ± standard deviation, <span class="html-italic">n</span> = 3, *; <span class="html-italic">p</span> &lt; 0.05, **; <span class="html-italic">p</span> &lt; 0.001, ***; <span class="html-italic">p</span> &lt; 0.0001.</p>
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<p>The effects of radiation quality and Nrf2i on osteogenesis. Normalized optical densities at 405 nm after alizarin red staining in the absence (●) and presence of Nrf2i (■) after different radiation qualities X-rays (<b>A</b>), protons (<b>B</b>) and carbon ions (<b>C</b>). The values are presented by mean ± standard deviation, <span class="html-italic">n</span> = 3, *; <span class="html-italic">p</span> &lt; 0.05, **; <span class="html-italic">p</span> &lt; 0.001, ***; <span class="html-italic">p</span> &lt; 0.0001.</p>
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<p>Alkaline phosphatase expression determined by Western blotting 21 days after osteogenesis of ADSCs in the presence (black bars) and the absence of Nrf2i (white bars) after exposure to the different radiation qualities of X-rays (<b>A</b>), protons (<b>B</b>) and carbon ions (<b>C</b>). The values are presented by mean ± standard deviation, <span class="html-italic">n</span> = 3, *; <span class="html-italic">p</span> &lt; 0.05; **; <span class="html-italic">p</span> &lt; 0.001 and ns: no significant change.</p>
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<p>Alkaline phosphatase expression determined by Western blotting 21 days after osteogenesis of ADSCs in the presence (black bars) and the absence of Nrf2i (white bars) after exposure to the different radiation qualities of X-rays (<b>A</b>), protons (<b>B</b>) and carbon ions (<b>C</b>). The values are presented by mean ± standard deviation, <span class="html-italic">n</span> = 3, *; <span class="html-italic">p</span> &lt; 0.05; **; <span class="html-italic">p</span> &lt; 0.001 and ns: no significant change.</p>
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23 pages, 6824 KiB  
Article
Unlocking the Secrets of Adipose Tissue: How an Obesity-Associated Secretome Promotes Osteoblast Dedifferentiation via TGF-β1 Signaling, Paving the Path to an Adipogenic Phenotype
by Yasmin Silva Forte, Vany Nascimento-Silva, Caio Andrade-Santos, Isadora Ramos-Andrade, Georgia Correa Atella, Luiz Guilherme Kraemer-Aguiar, Paulo Roberto Falcão Leal, Mariana Renovato-Martins and Christina Barja-Fidalgo
Cells 2024, 13(17), 1418; https://doi.org/10.3390/cells13171418 - 25 Aug 2024
Viewed by 466
Abstract
Background: Obesity poses a significant global health challenge, given its association with the excessive accumulation of adipose tissue (AT) and various systemic disruptions. Within the adipose microenvironment, expansion and enrichment with immune cells trigger the release of inflammatory mediators and growth factors, which [...] Read more.
Background: Obesity poses a significant global health challenge, given its association with the excessive accumulation of adipose tissue (AT) and various systemic disruptions. Within the adipose microenvironment, expansion and enrichment with immune cells trigger the release of inflammatory mediators and growth factors, which can disrupt tissues, including bones. While obesity’s contribution to bone loss is well established, the direct impact of obese AT on osteoblast maturation remains uncertain. This study aimed to explore the influence of the secretomes from obese and lean AT on osteoblast differentiation and activity. Methods: SAOS-2 cells were exposed to the secretomes obtained by culturing human subcutaneous AT from individuals with obesity (OATS) or lean patients, and their effects on osteoblasts were evaluated. Results: In the presence of the OATS, mature osteoblasts underwent dedifferentiation, showing an increased proliferation accompanied by a morphological shift towards a mesenchymal phenotype, with detrimental effects on osteogenic markers and the calcification capacity. Concurrently, the OATS promoted the expression of mesenchymal and adipogenic markers, inducing the formation of cytoplasmic lipid droplets in SAOS-2 cells exposed to an adipogenic differentiation medium. Additionally, TGF-β1 emerged as a key mediator of these effects, as the OATS was enriched with this growth factor. Conclusions: Our findings demonstrate that obese subcutaneous AT promotes the dedifferentiation of osteoblasts and increases the adipogenic profile in these cells. Full article
(This article belongs to the Section Cellular Pathology)
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Graphical abstract

Graphical abstract
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<p>Secretome of obese adipose tissue enhanced osteoblast proliferation and changed cell morphology. (<b>A</b>–<b>C</b>) SAOS-2 cells were incubated in medium without secretome (0% FBS), medium with 10% FBS without secretome (CTRL), or treated with lean adipose tissue secretome (20% LATS) or obese adipose tissue secretome (20% OATS) for 48 h. (<b>A</b>) OATS increased cell viability, as assessed by MTT assay. (<b>B</b>,<b>C</b>) OATS increased cell proliferation, as assessed by DAPI-stained cell counting after 48 h. (<b>D</b>) OATS induced alterations in SAOS-2 cell morphology, which assumed elongated spindle shape in 72 h. Images are representative of six independent experiments. Data are expressed as mean ± SD of 5–6 subjects per group. One-way ANOVA–Bonferroni post-test was performed; ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001, NS, Not significant.</p>
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<p>Secretome of obese adipose tissue reduced early and late osteoblast differentiation markers and impaired extracellular matrix mineralization. SAOS-2 cells incubated in osteogenic differentiation medium (O.D.M) were treated with LATS, OATS, or 10% FBS (CTRL) for 7 days. (<b>A</b>–<b>C</b>) Protein expression of early and late osteoblast differentiation markers was analyzed. Alkaline phosphatase (ALP) (<b>A</b>); collagen type I (COL1A1) (<b>B</b>); and osteopontin (OPN) (<b>C</b>). (<b>D</b>,<b>E</b>) Treatment with OATS (20%) inhibited extracellular matrix mineralization, as assessed by alizarin red staining (<b>D</b>) and quantified by D.O. (<b>E</b>) in cells cultured in O.D.M. Data are expressed as mean ± SD for groups of 7–9 subjects. One-way ANOVA–Bonferroni post-test was used; * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001, NS, Not significant.</p>
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<p>Secretome of obese adipose tissue enhanced mesenchymal marker expression of osteoblasts. SAOS-2 cells incubated in osteogenic differentiation medium (O.D.M) were treated with LATS, OATS, or 10% FBS (CTRL) for 3 days and expression of mesenchymal markers was evaluated. (<b>A</b>,<b>C</b>,<b>E</b>) Increased immunofluorescence using Alexa Fluor 555 was observed in cells treated with 20% OATS for CD90 (<b>A</b>), vimentin (<b>C</b>), and α-smooth muscle actin (α-SMA) (<b>E</b>). DAPI-stained nuclei are shown in blue. Representative images of 4 independent experiments (600×). (<b>B</b>,<b>D</b>,<b>F</b>) Protein expression of CD90 (<b>B</b>), vimentin (<b>D</b>), and α-SMA was increased by OATS (<b>F</b>). Data are expressed as mean ± SD per group of 6 subjects. One-way ANOVA–Bonferroni post-test was used; * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001, NS, Not significant.</p>
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<p>Obese adipose tissue secretome impacts integrin β1 expression and FAK-β-catenin signaling pathway. (<b>A</b>–<b>C</b>) SAOS-2 cells were treated with LATS, OATS, or 10% FBS (CTRL) for 7 days. (<b>A</b>–<b>C</b>) Expression of integrin β1 (<b>A</b>), integrin α2 (<b>B</b>), and integrin α5 (<b>C</b>). (<b>D</b>,<b>E</b>) Phosphorylation of focal adhesion kinase (<sup>Tyr397</sup>pFAK) (<b>D</b>) and β-catenin (<sup>Ser33−37/Thr41</sup>pβCat) (<b>E</b>). Data are expressed as mean ± SD per groups of 5–6 subjects. One-way ANOVA–Bonferroni post-test was used; * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01, NS, Not significant.</p>
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<p>Obese adipose tissue secretome stimulates adipogenic marker expression and lipid accumulation in osteobasts. (<b>A</b>,<b>B</b>) SAOS-2 cells were treated with LATS, OATS, or 10% FBS (CTRL) for 7 days. PPAR-γ (<b>A</b>) and CEBP-α (<b>B</b>) protein expression was analyzed. Data are expressed as mean ± SD of 4 (<b>A</b>) and 6 (<b>B</b>) subjects. (<b>C</b>–<b>E</b>) Cells were treated with LATS, OATS, or 10% FBS (CTRL) for 72 h, and further cultured in adipogenic differentiation medium from 7 to 10 days. (<b>C</b>) PPAR-γ protein expression (after 7 days). Data are mean ± SD of 5 subjects per groups. (<b>D</b>) OATS (20%) treatment increased lipid droplet accumulation in SAOS-2 cells, as indicated by enhanced oil red-O staining after 10 days of incubation in adipogenic differentiation medium. Representative images (400×), with four subjects per group. (<b>E</b>): OATS (20%) also increased immunofluorescence staining for perilipin (Alexa Fluor 555) after 3 days of incubation in adipogenic differentiation medium; representative images (1000×) of four subjects per group. INSERT: highlighted perilipin (in red) surrounding intracellular lipid droplets, as indicated by white arrows. One-way ANOVA followed by the Bonferroni post-test (* <span class="html-italic">p</span> &lt; 0.05) was used for the statistical analysis.</p>
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<p>TGF-β1 stimulation induced effects similar to OATS on SAOS-2 cells. (<b>A</b>) Quantification of TGF-β concentration in OATS and LATS. (<b>B</b>–<b>D</b>) Effect of TGF-β1 on mesenchymal and osteogenic markers: CD90 (<b>B</b>), osteopontin (OPN) (<b>C</b>), and CEBP-α (<b>D</b>). Data are expressed as mean ± SD per group of at least 4 subjects. (<b>E</b>,<b>F</b>) TGF-β1 inhibited ECM mineralization: SAOS-2 cells were incubated in O.D.M. and treated for 10 days with rTGF-β1 (20, 30, or 40 ng/mL) or 10% FBS (CTRL). rTGF-β1 diminished ECM deposition, as observed through lower alizarin red staining (<b>E</b>) and further quantified by D.O. (<b>F</b>). Representative images (40×). Data are expressed as mean ± SD per group of at least 4 subjects. One-way ANOVA–Bonferroni post-test was performed; * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001, NS, Not significant.</p>
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<p>TGF-β blockade attenuated effects of OATS on osteoblasts. (<b>A</b>) SAOS-2 cell viability (MTT assay) in presence of LY210961 (iTGF-β: 0.1–2.0 μM) for 48 h. (<b>B</b>–<b>E</b>) iTGF-β (1 μM) treatment inhibited OATS (20%)-induced changes in cell morphology (after 3 days), preventing osteoblasts from assuming mesenchymal-type shape (<b>B</b>) and inhibiting osteoblast proliferation, as assessed by DAPI-stained cell counting after 48 h (<b>C</b>,<b>D</b>). Treatment with iTGF-β impaired OATS inhibitory effect on ECM mineralization, as observed through increasing alizarin red staining in cells treated with 20% OATS+ iTGF-β (1 µM) (<b>E</b>,<b>F</b>)<b>.</b> Representative images (40×). Data are expressed as mean ± SD for groups of 4–5 subjects. One-way ANOVA followed by Bonferroni post-test was used (* <span class="html-italic">p</span> &lt; 0.05, *** <span class="html-italic">p</span> &lt; 0.001, NS, Not significant).</p>
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<p>Blockade of TGF-β inhibited OATS-induced PPAR-γ expression and nuclear translocation. Treatment with 20% OATS for 72 h increased PPAR-γ immunofluorescence (ALEXA 555, red) in nuclei of DAPI-stained SAOS-2 cells. Incubation with iTGF-β (1 µM) suppressed OATS-induced increase in PPAR-γ expression (20% OATS+ iTGF-β). Representative images (1000× magnification) were obtained from at least three samples per group.</p>
Full article ">Scheme 1
<p>Adipose tissue secretome preparation and experimental design. After adipose tissue secretome obtainment, SAOS-2 cells were treated with the lean adipose tissue secretome (LATS), the obese adipose tissue secretome (OATS), or no secretome (CTRL). Proliferation and viability assays, immunofluorescence, alizarin red staining, a Western blot, and a cell morphology analysis were performed at specific time points.</p>
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<p>Adipogenic transdifferentiation experimental design. SAOS-2 cells were pretreated with the lean adipose tissue secretome (LATS), the obese adipose tissue secretome (OATS), or no secretome (CTRL) for 72 h. After that, the cells were incubated in adipogenic differentiation culture media. Immunofluorescence, oil red staining, and a Western blot were performed at specific time points.</p>
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15 pages, 3310 KiB  
Article
Photobiomodulation Dose–Response on Adipose-Derived Stem Cell Osteogenesis in 3D Cultures
by Daniella Da Silva, Anine Crous and Heidi Abrahamse
Int. J. Mol. Sci. 2024, 25(17), 9176; https://doi.org/10.3390/ijms25179176 - 23 Aug 2024
Viewed by 363
Abstract
Osteoporosis and other degenerative bone diseases pose significant challenges to global healthcare systems due to their prevalence and impact on quality of life. Current treatments often alleviate symptoms without fully restoring damaged bone tissue, highlighting the need for innovative approaches like stem cell [...] Read more.
Osteoporosis and other degenerative bone diseases pose significant challenges to global healthcare systems due to their prevalence and impact on quality of life. Current treatments often alleviate symptoms without fully restoring damaged bone tissue, highlighting the need for innovative approaches like stem cell therapy. Adipose-derived mesenchymal stem cells (ADMSCs) are particularly promising due to their accessibility, abundant supply, and strong differentiation potential. However, ADMSCs tend to favor adipogenic pathways, necessitating the use of differentiation inducers (DIs), three-dimensional (3D) hydrogel environments, and photobiomodulation (PBM) to achieve targeted osteogenic differentiation. This study investigated the combined effects of osteogenic DIs, a fast-dextran hydrogel matrix, and PBM at specific wavelengths and fluences on the proliferation and differentiation of immortalized ADMSCs into osteoblasts. Near-infrared (NIR) and green (G) light, as well as their combination, were used with fluences of 3 J/cm2, 5 J/cm2, and 7 J/cm2. The results showed statistically significant increases in alkaline phosphatase levels, a marker of osteogenic differentiation, with G light at 7 J/cm2 demonstrating the most substantial impact on ADMSC differentiation. Calcium deposits, visualized by Alizarin red S staining, appeared as early as 24 h post-treatment in PBM groups, suggesting accelerated osteogenic differentiation. ATP luminescence assays indicated increased proliferation in all experimental groups, particularly with NIR and NIR-G light at 3 J/cm2 and 5 J/cm2. MTT viability and LDH membrane permeability assays confirmed enhanced cell viability and stable cell health, respectively. In conclusion, PBM significantly influences the differentiation and proliferation of hydrogel-embedded immortalized ADMSCs into osteoblast-like cells, with G light at 7 J/cm2 being particularly effective. These findings support the combined use of 3D hydrogel matrices and PBM as a promising approach in regenerative medicine, potentially leading to innovative treatments for degenerative bone diseases. Full article
(This article belongs to the Special Issue Cells and Molecules in Bone Remodeling and Repair)
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<p>The detection of alkaline phosphatase levels in differentiated immortalized adipose-derived mesenchymal stem cells was measured at 24 h and 7 days post-photobiomodulation. At 24 h, a statistically significant increase in ALP levels was observed in the control group compared to the standard. Additionally, all experimental groups showed a statistically significant increases in ALP levels compared to both the standard and control groups. Specifically, the G wavelength at 3 J/cm<sup>2</sup> and 7 J/cm<sup>2</sup> exhibited the most significant increase in ALP levels among the experimental groups. At 7 days, there was a notable rise in ALP levels in the control group compared to the standard group, and all experimental groups showed significant increases compared to the standard and control groups. Moreover, the G and NIR-G experimental PBM groups demonstrated an overall increase in ALP levels across 5 J/cm<sup>2</sup> and 7 J/cm<sup>2</sup> fluences at 7 days post-treatment. The data are expressed as mean ± SE. * <span class="html-italic">p</span> &lt; 0.05, *** <span class="html-italic">p</span> &lt; 0.001. Black stars (*) indicate comparisons between the specified samples and the standard group. Blue stars (<span style="color:#0432FF">*</span>) denote comparisons between the experimental samples and the control group. Comparisons among the experimental PBM groups are marked with red stars (<span style="color:red">*</span>). The sample size was n = 3.</p>
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<p>Morphological characterization of adipose-derived mesenchymal stem cells using Alizarin red S staining. The observation of vibrant orange to red deposits at both 24 h and 7 days post-photobiomodulation treatment indicates calcium deposition, suggesting potential osteogenic differentiation (III, IV, VII, IX, X, XIII, XIV, XVII, XVIII, XIX, XX, XXIV, XXVII, XXVIII, and XXIX). (10× magnification and 50 μm scale bar).</p>
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<p>Cell proliferation: ATP luminescence assay of the differentiated immortalized adipose-derived mesenchymal stem cells’ ATP levels measured at 24 h and 7 days post-photobiomodulation. At 24 h, all experimental groups showed a statistically significant increase in ATP levels compared to the standard and control groups. At 7 days, a significant rise in ATP levels was observed in the control, NIR, and G PBM groups compared to the standard at fluences of 3 J/cm<sup>2</sup> and 7 J/cm<sup>2</sup>. However, the NIR-G experimental PBM group exhibited an overall decline in ATP levels across all three fluences at 7 days post-treatment. The data are presented as mean ± SE. Significance levels are denoted as follows: * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001. Black stars (*) represent comparisons between the specified samples and the standard group, while blue stars (<span style="color:#0070C0">*</span>) indicate comparisons between the experimental samples and the control group. Comparisons among the experimental PBM groups are marked with red stars (<span style="color:red">*</span>). The sample size was n = 3.</p>
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<p>Cell viability analysis of immortalized adipose-derived mesenchymal stem cells at 24 h and 7 days post-photobiomodulation treatment. The MTT assay revealed a statistically significant increase in cell viability across all experimental groups at both time points compared to the standard and control groups. Additionally, the NIR and NIR-G experimental groups showed statistically significant increases in cell viability compared to the G experimental group at all three fluences, both at 24 h and 7 days post-treatment. The data are shown as mean ± SE. Significance levels are indicated by * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, and *** <span class="html-italic">p</span> &lt; 0.001. Black stars (*) denote comparisons between the specified samples and the standard group, blue stars (<span style="color:#0070C0">*</span>) show comparisons between the experimental samples and the control group, and red stars (<span style="color:red">*</span>) indicate comparisons among the experimental PBM groups. The sample size is n = 3.</p>
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<p>Membrane permeability analysis: The lactate dehydrogenase cytotoxicity assay indicated a significant increase in LDH leakage at 24 h post-PBM treatment in both the control and all experimental groups compared to the standard cell group. Importantly, despite the observed increase in LDH leakage, it did not lead to cell fatality, as evidenced by a comparison with the experimental cytotoxic positive control. The data are presented as mean ± SE. Significance levels are marked as follows: *** <span class="html-italic">p</span> &lt; 0.001. Black stars (*) indicate comparisons between the specified samples and the standard group. The sample size is n = 3.</p>
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<p>The experimental procedure: Immortalized adipose-derived stem cells were revived and sub-cultured until reaching the desired density. Osteogenic differentiation was induced using dexamethasone, β-glycerol phosphate disodium, and ascorbic acid within a fast-dextran hydrogel disc over several days of incubation. The cells were then exposed to different fluences (3 J/cm<sup>2</sup>, 5 J/cm<sup>2</sup>, and 7 J/cm<sup>2</sup>) at wavelengths of Near-Infrared 825 nm, Green 525 nm, and a combination thereof to enhance both osteoblastic differentiation and cellular proliferation. Two experimental conditions were tested: one where cells within the hydrogel disc received no osteogenic inducers or photobiomodulation treatment, and another where cells embedded within the hydrogel disc received only osteogenic inducers without photobiomodulation. Cell samples were collected at 24 h and 7 days post-irradiation. Alkaline phosphatase levels were quantified using spectrophotometry as an early protein marker, and calcium deposits were visualized using Alizarin red S staining. Biochemical analyses included ATP cell proliferation, MTT cell viability, and LDH membrane permeability assessments.</p>
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12 pages, 3435 KiB  
Article
Composite Mineralized Collagen/Polycaprolactone Scaffold-Loaded Microsphere System with Dual Osteogenesis and Antibacterial Functions
by Yuzhu He, Qindong Wang, Yuqi Liu, Zijiao Zhang, Zheng Cao, Shuo Wang, Xiaoxia Ying, Guowu Ma, Xiumei Wang and Huiying Liu
Polymers 2024, 16(17), 2394; https://doi.org/10.3390/polym16172394 - 23 Aug 2024
Viewed by 328
Abstract
Biomaterials play an important role in treating bone defects. The functional characteristics of scaffolds, such as their structure, mechanical strength, and antibacterial and osteogenesis activities, effectively promote bone regeneration. In this study, mineralized collagen and polycaprolactone were used to prepare loaded porous scaffolds [...] Read more.
Biomaterials play an important role in treating bone defects. The functional characteristics of scaffolds, such as their structure, mechanical strength, and antibacterial and osteogenesis activities, effectively promote bone regeneration. In this study, mineralized collagen and polycaprolactone were used to prepare loaded porous scaffolds with bilayer-structured microspheres with dual antibacterial and osteogenesis functions. The different drug release mechanisms of PLGA and chitosan in PLGA/CS microspheres caused differences in the drug release models in terms of the duration and rate of Pac-525 and BMP-2 release. The prepared PLGA(BMP-2)/CS(Pac-525)@MC/PCL scaffolds were analyzed in terms of physical characteristics, bioactivity, and antibacterial properties. The scaffolds with a dimensional porous structure showed similar porosity and pore diameter to cancellous bone. The release curve of the microspheres and scaffolds with high encapsulation rates displayed the two-stage release of Pac-525 and BMP-2 over 30 days. It was found that the scaffolds could inhibit S. aureus and E. coli and then promote ALP activity. The PLGA(BMP-2)/CS(Pac-525)@MC/PCL scaffold could be used as a dual delivery system to promote bone regeneration. Full article
(This article belongs to the Special Issue Smart and Bio-Medical Polymers)
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<p>Morphology of microspheres and scaffolds. (<b>A</b>) SEM micrographs of PLGA<sub>(BMP-2)</sub> microspheres; (<b>B</b>,<b>C</b>) SEM images of PLGA<sub>(BMP-2)</sub>/CS<sub>(Pac-525)</sub> microspheres ((<b>B</b>) surface; (<b>C</b>) cross-section); (<b>D</b>) CLSM images of PLGA<sub>(Nile)</sub>/CS<sub>(FITC)</sub> microspheres (PLGA: red; CS: green); (<b>E</b>,<b>F</b>) SEM images of PLGA<sub>(BMP-2)</sub>/CS<sub>(Pac-525)</sub>@MC/PCL scaffolds.</p>
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<p>Physical characteristics of microspheres and scaffolds. (<b>A</b>) The diameter range of PLGA<sub>(BMP-2)</sub>/CS<sub>(Pac-525)</sub> microsphere; (<b>B</b>) the pore size range of PLGA<sub>(BMP-2)</sub>/CS<sub>(Pac-525)</sub>@MC/PCL scaffolds.</p>
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<p>The cumulative release of drugs in microspheres and scaffolds. (<b>A</b>) The cumulative release curve of BMP-2 in PLGA<sub>(BMP-2)</sub>/CS microspheres and PLGA<sub>(BMP-2)</sub>/CS@MC/PCL scaffolds; (<b>B</b>) the cumulative release curve of Pac-525 in PLGA/CS<sub>(Pac-525)</sub> microspheres and PLGA/CS<sub>(Pac-525)</sub>@MC/PCL scaffolds.</p>
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<p>SEM and CLSM images of BMSCs on scaffolds. (<b>A</b>,<b>D</b>) On MC/PCL scaffolds; (<b>B</b>,<b>E</b>) on PLGA/CS@MC/PCL scaffolds; (<b>C</b>,<b>F</b>) on PLGA<sub>(BMP-2)</sub>/CS@MC/PCL scaffolds. (Red: cytoskeleton; Blue: nucleus).</p>
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<p>Bioactivity of PLGA<sub>(BMP-2)</sub>/CS@MC/PCL scaffolds. (<b>A</b>) BMSCs’ viability on scaffolds on the 1st, 3rd and 5th days; (<b>B</b>) ALP activity of BMSCs on scaffolds at 14 days (* <span class="html-italic">p</span> &lt; 0.05).</p>
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<p>The antibacterial activity of PLGA<sub>(BMP-2)</sub>/CS<sub>(Pac-525)</sub>@MC/PCL scaffolds. The antibacterial activity of the released solution on <span class="html-italic">E. coli</span> (<b>A</b>) and <span class="html-italic">S. aureus</span> (<b>B</b>).</p>
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33 pages, 20993 KiB  
Review
Nanoparticles in Bone Regeneration: A Narrative Review of Current Advances and Future Directions in Tissue Engineering
by Samira Farjaminejad, Rosana Farjaminejad and Franklin Garcia-Godoy
J. Funct. Biomater. 2024, 15(9), 241; https://doi.org/10.3390/jfb15090241 - 23 Aug 2024
Viewed by 553
Abstract
The rising demand for effective bone regeneration has underscored the limitations of traditional methods like autografts and allografts, including donor site morbidity and insufficient biological signaling. This review examines nanoparticles (NPs) in tissue engineering (TE) to address these challenges, evaluating polymers, metals, ceramics, [...] Read more.
The rising demand for effective bone regeneration has underscored the limitations of traditional methods like autografts and allografts, including donor site morbidity and insufficient biological signaling. This review examines nanoparticles (NPs) in tissue engineering (TE) to address these challenges, evaluating polymers, metals, ceramics, and composites for their potential to enhance osteogenesis and angiogenesis by mimicking the extracellular matrix (ECM) nanostructure. The methods involved synthesizing and characterizing nanoparticle-based scaffoldsand integrating hydroxyapatite (HAp) with polymers to enhance mechanical properties and osteogenic potential. The results showed that these NPs significantly promote cell growth, differentiation, and bone formation, with carbon-based NPs like graphene and carbon nanotubes showing promise. NPs offer versatile, biocompatible, and customizable scaffolds that enhance drug delivery and support bone repair. Despite promising results, challenges with cytotoxicity, biodistribution, and immune responses remain. Addressing these issues through surface modifications and biocompatible molecules can improve the biocompatibility and efficacy of nanomaterials. Future research should focus on long-term in vivo studies to assess the safety and efficacy of NP-based scaffolds and explore synergistic effects with other bioactive molecules or growth factors. This review underscores the transformative potential of NPs in advancing BTE and calls for further research to optimize these technologies for clinical applications. Full article
(This article belongs to the Special Issue Biomaterials in Bone Reconstruction)
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<p>Classification of NPs in BTE. A. Inorganic NPs: includes metals (e.g., Ag, C, Zr, Ni, Au, Aluminum), and ceramics (e.g., HA). B. Organic NPs: includes lipid-based materials and polymers (e.g., chitosan), PLA, PLGA, PEG, PFF, PCL, and PGA, poly(glycolic acid). 1 PLA, poly(lactic acid). 2 PLGA, poly(lactic-glycolic acid). 3 PEG, polyethylene glycol. 4 PFF, poly(propylene fumarate). 5 PCL, polycaprolactone. 6 PGA, poly(glycolic acid). 7 Ag, silver. 8 Cu, Copper. 9 Zr, zirconium. 10 Ni, nickel. 11, Au, gold.</p>
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<p>Summary of NP Applications in Bone, reprinted from Ref. [<a href="#B23-jfb-15-00241" class="html-bibr">23</a>].</p>
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<p>(<b>a</b>) The reactivity of clays primarily depends on their swelling capacity. Kaolinite (belonging to the 1:1 clay family) and talc and pyrophyllite (members of the 2:1 clay family) have no structural charges, making them non-swelling with low adsorption capacity. Vermiculite and illite, despite having a high layer charge that limits their swelling and gelling tendencies, possess relatively high surface area and cation exchange capacity. Smectites, with their relatively low layer charge, can completely dissociate in water, leading to unique rheological/gel-forming properties and surface reactivity [<a href="#B40-jfb-15-00241" class="html-bibr">40</a>]. (<b>b</b>) Structure of kaolinite [<a href="#B37-jfb-15-00241" class="html-bibr">37</a>]. (<b>c</b>) Illustration of the structure and composition of Laponite RD nanoclay [<a href="#B36-jfb-15-00241" class="html-bibr">36</a>]. (<b>d</b>) Schematic view of nanosized LAPONITE disks and inter-layer space between these disks; (<b>e</b>) the chemical structure of LAPONITE disks and intercalation of cationic ions and drugs (e.g., mafenide) between the inter-layer space [<a href="#B37-jfb-15-00241" class="html-bibr">37</a>].</p>
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<p>The various dimensionalities of carbon-based NPs and their structures are illustrated, including 0D fullerenes, 1D single-walled and multi-walled carbon nanotubes (SWCNT, MWCNT), 2D graphene oxide and reduced graphene oxide, and 3D graphite and diamond.</p>
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<p>Diagram showing the role of CNTs as scaffold composites in BTE and regeneration, reprinted from Ref. [<a href="#B147-jfb-15-00241" class="html-bibr">147</a>].</p>
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17 pages, 768 KiB  
Review
Osteoporosis and Bone Fragility in Children: Diagnostic and Treatment Strategies
by Giuseppe Cannalire, Giacomo Biasucci, Lorenzo Bertolini, Viviana Patianna, Maddalena Petraroli, Simone Pilloni, Susanna Esposito and Maria Elisabeth Street
J. Clin. Med. 2024, 13(16), 4951; https://doi.org/10.3390/jcm13164951 - 22 Aug 2024
Viewed by 542
Abstract
The incidence of osteoporosis in children is increasing because of the increased survival rate of children with chronic diseases and the increased use of bone-damaging drugs. As childhood bone fragility has several etiologies, its management requires a thorough evaluation of all potentially contributing [...] Read more.
The incidence of osteoporosis in children is increasing because of the increased survival rate of children with chronic diseases and the increased use of bone-damaging drugs. As childhood bone fragility has several etiologies, its management requires a thorough evaluation of all potentially contributing pathogenetic mechanisms. This review focuses on the main causes of primary and secondary osteoporosis and on the benefits and limits of the different radiological methods currently used in clinical practice for the study of bone quality. The therapeutic and preventive strategies currently available and the most novel diagnostic and treatment strategies are also presented. Optimal management of underlying systemic conditions is key for the treatment of bone fragility in childhood. DXA still represents the gold standard for the radiologic evaluation of bone health in children, although other imaging techniques such as computed tomography and ultrasound evaluations, as well as REMS, are increasingly studied and used. Bisphosphonate therapy is the gold standard for pharmacological treatment in both primary and secondary pediatric osteoporosis. Evidence and experience are building up relative to the use of monoclonal antibodies such as denosumab in cases of poor response to bisphosphonates in specific conditions such as osteogenesis imperfecta, juvenile Paget’s disease and in some cases of secondary osteoporosis. Lifestyle interventions including adequate nutrition with adequate calcium and vitamin D intake, as well as physical activity, are recommended for prevention. Full article
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<p>Diagnostic workup for children with suspicion of osteoporosis.</p>
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