Human Bone Marrow Mesenchymal Cells Research Articles

Investigation of the Relationship between Surface Features, Protein Adsorption, and Osteoimmunomodulation: The Case of a Chemically Treated Titanium Alloy.

This paper deals with the combined effects of immune response and osseointegration because of the lack of comprehensive studies on this topic. An antibacterial Ti surface was considered because of the high risk of infection for titanium bone implants. A chemically treated Ti6Al4 V alloy [Ti64(Sr-Ag)] with a microporous and Sr-Ag doped surface was compared to a polished version (Ti64) regarding protein adsorption (albumin and fibronectin) and osteoimmunomodulation. Characterization via fluorescence microscopy and zeta potential showed a continuous fibronectin layer on Ti64(Sr-Ag), even with preadsorbed albumin, while it remained filamentous on Ti64. Macrophages (differentiated from THP-1 monocytes) were cultured on both surfaces, with viability and cytokine release analyzed. Differently from Ti64, Ti64(Sr-Ag) promoted early anti-inflammatory responses and significant downregulation of VEGF. Ti64(Sr-Ag) also enhanced human bone marrow mesenchymal cell differentiation toward osteoblasts, when a macrophage-conditioned medium was used, influencing ALP production. Surface properties in relation to protein adsorption and osteoimmunomodulation were discussed.

Pro-Osteogenic Effect of the Nutraceutical BlastiMin Complex® in Women with Osteoporosis or Osteopenia: An Open Intervention Clinical Trial

Osteoporosis is a chronic disease that affects millions of patients worldwide and is characterized by low bone mineral density (BMD) and increased risk of fractures. Notably, natural molecules can increase BMD and exert pro-osteogenic effects. Noteworthily, the nutraceutical BlastiMin Complex® (Mivell, Italy, European Patent Application EP4205733A1) can induce differentiation of human bone marrow mesenchymal stem cells (BM-MSCs) in osteoblasts and can exert in vitro pro-osteogenic and anti-inflammatory effects. Thus, the purpose of this study was to verify the effects of BlastiMin Complex® on bone turnover markers (BTMs) and BMD in patients with senile and postmenopausal osteopenia or osteoporosis. The efficacy of BlastiMin Complex® on BTMs in serum was evaluated through biochemical assays. BMD values were analyzed by dual-energy X-ray absorptiometry (DXA) and Radiofrequency Echographic Multi Spectrometry (R.E.M.S.) techniques, and the SNPs with a role in osteoporosis development were evaluated by PCR. Clinical data obtained after 12 months of treatment showed an increase in bone turnover index, a decrease in C-reactive protein levels, and a remarkable increase in P1NP levels, indicating the induction of osteoblast proliferation and activity in the cohort of 100% female patients recruited for the study. These findings show that the nutraceutical BlastiMin Complex® could be used as an adjuvant in combination with synthetic drugs for the treatment of osteoporosis pathology.

Oxaliplatin-induced upregulation of exosomal miR-424-3p derived from human bone marrow mesenchymal stem cells attenuates progression of gastric cancer cells

Chemotherapy, particularly with oxaliplatin, is a key treatment for advanced gastric cancer (GC), and exosomes derived from human bone marrow mesenchymal stem cells (hBM-MSCs) play a vital role in the tumor microenvironment. The study aims to elucidate the previously unexplored role of exosomes derived from hBM-MSCs in GC tumorigenesis, especially under the influence of chemotherapy. We conducted an experimental study, utilizing miRNA sequencing and biological experiments, to analyze the tumorigenicity of exosomal miR-424-3p secreted by hBM-MSCs and its target gene RHOXF2 in GC cell lines. The results were confirmed through experimentation using a xenograft mouse model. This study demonstrated the role of hBM-MSCs in the GC microenvironment, focusing on their epithelial-mesenchymal transition (EMT) facilitation through exosomes, which led to enhanced tumorigenicity in GC cells. Intriguingly, this pro-tumor effect was abrogated when hBM-MSCs were treated with oxaliplatin. Exosomal miRNA sequencing revealed that oxaliplatin can upregulate the levels of miR-424-3p in exosomes secreted by hBM-MSCs, thereby inhibiting the EMT process in GC cells. Furthermore, miR-424-3p was identified to target and downregulate RHOXF2 expression, impeding the malignant behavior of GC cells both in vitro and in the mouse model. These findings uncover a potential hidden mechanism of oxaliplatin's anti-tumor action and propose the delivery of miR-424-3p via exosomes as a promising avenue for anti-tumor therapy.

Activation of the BMP2/SMAD4 signaling pathway for enhancing articular cartilage regeneration of mesenchymal stem cells utilizing chitosan/alginate nanoparticles on 3D extracellular matrix scaffold

This study investigated the efficacy of using chitosan/alginate nanoparticles loaded with recombinant human bone morphogenetic-2 (rhBMP-2) and SMAD4 encoding plasmid to enhance the chondrogenesis of human bone marrow mesenchymal stem cells (hBM-MSCs) seeded on an extracellular matrix (ECM). The research treatments included the stem cells treated with the biological cocktail (BC), negative control (NC), hBM-MSCs with chondrogenic medium (MCM), hBM-MSCs with naked rhBMP-2 and chondrogenic medium (NB/C), and hBM-MSCs with naked rhBMP-2 and chondrogenic medium plus SMAD4 encoding plasmid transfected with polyethyleneimine (PEI) (NB/C/S/P). The cartilage differentiation was performed with real-time quantitative PCR analysis and alizarin blue staining. The data indicated that the biological cocktail (BC) exhibited significantly higher expression of cartilage-related genes compared to significant differences with MCM and negative control (NC) on chondrogenesis. In the (NB/C/S/P), the expression levels of SOX9 and COLX were lower than those in the BC group. The expression pattern of the ACAN gene was similar to COL2A1 changes suggesting that it holds promising potential for cartilage regeneration.

Electrical Responsive Coating with a Multilayered TiO2-SnO2-RuO2 Heterostructure on Ti for Controlling Antibacterial Ability and Improving Osseointegration.

The bacterial infection and poor osseointegration of Ti implants could significantly compromise their applications in bone repair and replacement. Based on the carrier separation ability of the heterojunction and the redox reaction of pseudocapacitive metal oxides, we report an electrically responsive TiO2-SnO2-RuO2 coating with a multilayered heterostructure on a Ti implant. Owing to the band gap structure of the TiO2-SnO2-RuO2 coating, electron carriers are easily enriched at the coating surface, enabling a response to the endogenous electrical stimulation of the bone. With the formation of SnO2-RuO2 pseudocapacitance on the modified surface, the postcharging mode can significantly change the surface chemical state of the coating due to the redox reaction, enhancing the antibacterial ability and osteogenesis-related gene expression of the human bone marrow mesenchymal stem cells. Owing to the attraction for Ca2+, only the negatively postcharged SnO2@RuO2 can promote apatite deposition. The in vivo experiment reveals that the S-SnO2@RuO2-NP could effectively kill the bacteria colonized on the surface and promote osseointegration with the synostosis bonding interface. Thus, negatively charging the electrically responsive coating of TiO2-SnO2-RuO2 is a good strategy to endow modified Ti implants with excellent antibacterial ability and osseointegration.

Development of Innovative Biocomposites with Collagen, Keratin and Hydroxyapatite for Bone Tissue Engineering.

This study follows the process for the development of an innovative biomimetic composite derived from bovine collagen with keratin, with hydroxyapatite being hybridized into its architecture, and it builds a comprehensive evaluation of the composite's characteristics. The novel biomimetic materials are tailored with special traits to be achieved for the repair of osteochondral defects (OCDs). The purpose of the present research is to create a reliable effective alternative to existing bone graft materials while leveraging the intrinsic properties of the components for enhanced osteoinduction and integration. The composites were characterized based on their morphological properties, including water absorption, through scanning electron microscopy (SEM), and their structural properties were characterized by Fourier-Transform Infrared Spectroscopy (FTIR). Biological performance was assessed in vitro using human bone marrow mesenchymal stem cells (BMSCs), focusing on cytotoxicity, cell viability, and the ability to support cell colonization with forthcoming results. This in vivo study illustrates the real potential that this class of novel composites exhibits in regard to bone and cartilage tissue engineering and encourages further exploration and development for future clinical applications.

Utilization of convolutional neural networks to analyze microscopic images for high-throughput screening of mesenchymal stem cells.

This work investigated the high-throughput classification performance of microscopic images of mesenchymal stem cells (MSCs) using a hyperspectral imaging-based separable convolutional neural network (CNN) (H-SCNN) model. Human bone marrow mesenchymal stem cells (hBMSCs) were cultured, and microscopic images were acquired using a fully automated microscope. Flow cytometry (FCT) was employed for functional classification. Subsequently, the H-SCNN model was established. The hyperspectral microscopic (HSM) images were created, and the spatial-spectral combined distance (SSCD) was employed to derive the spatial-spectral neighbors (SSNs) for each pixel in the training set to determine the optimal parameters. Then, a separable CNN (SCNN) was adopted instead of the classic convolutional layer. Additionally, cultured cells were seeded into 96-well plates, and high-functioning hBMSCs were screened using both manual visual inspection (MV group) and the H-SCNN model (H-SCNN group), with each group consisting of 96 samples. FCT served as the benchmark to compare the area under the curve (AUC), F1 score, accuracy (Acc), sensitivity (Sen), specificity (Spe), positive predictive value (PPV), and negative predictive value (NPV) between the manual and model groups. The best classification Acc was 0.862 when using window size of 9 and 12 SSNs. The classification Acc of the SCNN model, ResNet model, and VGGNet model gradually increased with the increase in sample size, reaching 89.56 ± 3.09, 80.61 ± 2.83, and 80.06 ± 3.01%, respectively at the sample size of 100. The corresponding training time for the SCNN model was significantly shorter at 21.32 ± 1.09 min compared to ResNet (36.09 ± 3.11 min) and VGGNet models (34.73 ± 3.72 min) (P < 0.05). Furthermore, the classification AUC, F1 score, Acc, Sen, Spe, PPV, and NPV were all higher in the H-SCNN group, with significantly less time required (P < 0.05). Microscopic images based on the H-SCNN model proved to be effective for the classification assessment of hBMSCs, demonstrating excellent performance in classification Acc and efficiency, enabling its potential to be a powerful tool in future MSCs research.

Exosomal lncRNA HCP5 derived from human bone marrow mesenchymal stem cells improves chronic periodontitis by miR-24-3p/HO1/P38/ELK1 pathway

ObjectiveThe present study aimed to explore the function of human bone marrow mesenchymal stem cells (hBMMSCs)-derived exosomal long noncoding RNA histocompatibility leukocyte antigen complex P5 (HCP5) in the osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) to improve chronic periodontitis (CP). MethodsExosomes were extracted from hBMMSCs. Alizarin red S staining was used to detect mineralised nodules. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to measure HCP5 and miR-24-3p expression. The mRNA and protein levels of alkaline phosphatase (ALP), osteocalcin, osterix, runt-related transcription factor 2, bone morphogenetic protein 2, osteopontin, fibronectin, collagen 1, heme oxygenase 1 (HO1), P38, and ETS transcription factor ELK1 (ELK1) were detected using RT-qPCR and Western blot. Enzyme-linked immunosorbent assay (ELISA) kits were used to determine the HO1 and carbon monoxide concentrations. Heme, biliverdin, and Fe2+ levels were determined using detection kits. Micro-computed tomography, hematoxylin and eosin staining, ALP staining, tartrate-resistant acid phosphatase staining, ELISA, and RT-qPCR were conducted to evaluate the effect of HCP5 on CP mice. Dual luciferase, RNA immunoprecipitation, and RNA pulldown experiments were performed to identify the interactions among HCP5, miR-24-3p, and HO1. ResultsThe osteogenic ability of hPDLSCs significantly increased when co-cultured with hBMMSCs or hBMMSCs exosomes. Overexpression of HCP5 and HO1 in hBMMSCs exosomes promoted the osteogenic differentiation of hPDLSCs, and knockdown of HCP5 repressed the osteogenic differentiation of hPDLSCs. HCP5 knockdown enhanced the inflammatory response and repressed osteogenesis in CP mice. MiR-24-3p overexpression diminished the stimulatory effect of HCP5 on the osteogenic ability of hPDLSCs. Mechanistically, HCP5 acted as a sponge for miR-24-3p and regulated HO1 expression, and HO1 activated the P38/ELK1 pathway. ConclusionHBMMSCs-derived exosomal HCP5 promotes the osteogenic differentiation of hPDLSCs and alleviates CP by regulating the miR-24-3p/HO1/P38/ELK1 signalling pathway.

Salvianolic Acid B Accelerates Osteoporotic Fracture Healing via LncRNA-MALAT1/miR-155-5p/HIF1A Axis

Background: Osteoporotic fracture is a pathological fracture secondary to osteoporosis, causing disabilities and a heavy burden to the patients. In the previous study, we found that salvianolic acid B (SalB) promoted the osteogenesis of Mesenchymal Stem Cells (MSCs). Objective: This study aimed to explore the role of SalB in osteoporotic fracture healing, as well as the potential molecular mechanism. Methods: Human bone marrow mesenchymal stem cells (hMSCs) were treated with SalB or PBS in vitro, and an osteoporotic fracture model in Sprague-Dawley (SD) rats was established successfully. SalB or PBS was locally injected at the fracture. Eight weeks later, microCT was used to compare the healing of osteoporotic fractures with or without SalB. The relative expressions of mRNAs were measured by qRT-PCR. Bioinformatics analysis, RT-PCR, and dual luciferase reporter assay were utilized to detect the interrelation of genes. Immunohistochemistry staining was used to test expressions of proteins. Results: In the present study, we found that SalB significantly increased the level of lncRNA-- MALAT1 in a dose-dependent manner. Additionally, silencing lncRNA-MALAT1 inhibited the expressions of osteogenesis-related marker genes and abolished the effect of SalB on osteogenesis. Also, we found that lncRNA-MALAT1 sponged miR-155-5p, and miR-155-5p directly targeted HIF-1α. Using the osteoporotic fracture healing model, our result demonstrated that local administration of SalB could promote both bone and type H vessel formation in the calluses. The mechanical test further showed that SalB could improve the mechanical properties of fractured femurs. Conclusion: Taken together, our study reported that SalB could promote osteogenesis and type H vessel formation to accelerate osteoporotic fracture healing through the lncRNA-- MALAT1/miR-155-5p/HIF-1α axis.

Glycinamide Facilitates Nanocomplex Formation and Functions Synergistically with Bone Morphogenetic Protein 2 to Promote Osteoblast Differentiation In Vitro and Bone Regeneration in a Mouse Calvarial Defect Model.

This study aimed to identify glycine analogs conducive to the formation of cell-absorbable nanocomplexes, enhancing collagen synthesis and subsequent osteogenesis in combination with BMP2 for improved bone regeneration. Glycine and its derivatives were assessed for their effects on osteogenic differentiation in MC3T3-E1 cells and human bone marrow mesenchymal stem cells (BMSCs) under osteogenic conditions or with BMP2. Osteogenic differentiation was assessed through alkaline phosphatase staining and real-time quantitative polymerase chain reaction (RT-qPCR). Nanocomplex formation was examined via scanning electron microscopy, circular dichroism, and ultraviolet-visible spectroscopy. In vivo osteogenic effects were validated using a mouse calvarial defect model, and bone regeneration was evaluated through micro-computed tomography and histomorphometric analysis. Glycine, glycine methyl ester, and glycinamide significantly enhanced collagen synthesis and ALP activity in conjunction with an osteogenic medium (OSM). GA emerged as the most effective inducer of osteoblast differentiation marker genes. Combining GA with BMP2 synergistically stimulated ALP activity and the expression of osteoblast markers in both cell lines. GA readily formed nanocomplexes, facilitating cellular uptake through strong electrostatic interactions. In an in vivo calvarial defect mouse model, the GA and BMP2 combination demonstrated enhanced bone volume, bone volume/tissue volume ratio, trabecular numbers, and mature bone formation compared to other combinations. GA and BMP2 synergistically promoted in vitro osteoblast differentiation and in vivo bone regeneration through nanocomplex formation. This combination holds therapeutic promise for individuals with bone defects, showcasing its potential for clinical intervention.

Fibroblast growth factor 23-mediated regulation of osteoporosis: Assessed via Mendelian randomization and invitro study.

Despite numerous investigations on the influence of fibroblast growth factor 23 (FGF23), α-Klotho and FGF receptor-1 (FGFR1) on osteoporosis (OP), there is no clear consensus. Mendelian randomization (MR) analysis was conducted on genome-wide association studies (GWASs)-based datasets to evaluate the causal relationship between FGF23, α-Klotho, FGFR1 and OP. The primary endpoint was the odds ratio (OR) of the inverse-variance weighted (IVW) approach. Furthermore, we stably transfected FGF23-mimic or siRNA-FGF23 into human bone marrow mesenchymal stem cells (hBMSCs) in culture and determined its cell proliferation and the effects on osteogenic differentiation. Using MR analysis, we demonstrated a strong correlation between serum FGF23 levels and Heel- and femoral neck-BMDs, with subsequent ORs of 0.919 (95% CI: 0.860-0.983, p = 0.014) and 0.751 (95% CI: 0.587-0.962; p = 0.023), respectively. The expression levels of FGF23 were significantly increased in femoral neck of patients with OP than in the control cohort (p < 0.0001). Based on our invitro investigation, after overexpression of FGF23, compared to the control group, the BMSC's proliferation ability decreased, the expression level of key osteogenic differentiation genes (RUNX2, OCN and OSX) significantly reduced, mineralized nodules and ALP activity significantly decreased. After silencing FGF23, it showed a completely opposite trend. Augmented FGF23 levels are causally associated with increased risk of OP. Similarly, FGF23 overexpression strongly inhibits the osteogenic differentiation of hBMSCs, thereby potentially aggravating the pathological process of OP.

Overexpression of NDNF Improves the Cytoprotective Effects of Aged Human Bone Marrow Mesenchymal Stem Cells by Modulating Oxidative Stress and Apoptosis.

The therapeutic potential of autologous stem cell transplantation for heart repair diminishes in the elderly due to stem cell aging. Rejuvenating aged stem cells to enhance their protective effects on injured cardiomyocytes is crucial for aging patients with heart failure. In this study, we aimed to investigate whether neuron-derived neurotrophic factor (NDNF) over-expression improves the protective effect of aged stem cells for injured cardiomyocytes and explore the underlying mechanism. Human bone marrow was collected from both young and old patients, and bone marrow mesenchymal stem cells (BMSCs) were cultured. Lentivirus expression vectors carrying NDNF genes were used to transfect aged BMSCs. Fatal hypoxia-induced injury in H9C2 cells served as an in vitro ischemia model. The conditioned medium from different BMSC groups was applied to assess the beneficial effects on hypoxia-induced damage in myocardial H9C2 cells. Results revealed that the conditioned medium of NDNF over-expressed old BMSCs increased H9C2 cell viability and reduced oxidative stress and apoptosis levels under fatal hypoxia. NDNF over-expressed old BMSCs exhibited an antiapoptotic role by upregulating the antiapoptotic gene Bcl-2 and downregulating the proapoptotic genes Bax. Additionally, the protective effects were mediated through the elevation of phosphorylated AKT. Our data support the promise of NDNF as a potential target to enhance the protective effects of autologous aged BMSCs on ischemic cardiomyocytes and then improve the curative effects of stem cell for ischemic heart injury in aged patients.

Three-Dimensional Mechanical Microenvironment Rescued the Decline of Osteogenic Differentiation of Old Human Jaw Bone Marrow Mesenchymal Stem Cells.

Resorption and atrophy of the alveolar bone, as two consequences of osteoporosis that remarkably complicate the orthodontic and prosthodontic treatments, contribute to the differentiated biological features and force-induced response of jaw bone marrow-derived mesenchymal stem cells (JBMSCs) in elderly patients. We isolated and cultured JBMSCs from adolescent and adult patients and then simulated the loading of orthodontic tension stress by constructing an in vitro three-dimensional (3D) stress loading model. The decline in osteogenic differentiation of aged JBMSCs was reversed by tensile stress stimulation. It is interesting to note that tension stimulation had a stronger effect on the osteogenic differentiation of elderly JBMSCs compared to the young ones, indicating a possible mechanism of aging rescue. High-throughput sequencing of microRNA (miRNAs) was subsequently performed before and after tension stimulation in all JBMSCs, followed by the comprehensive comparison of mechanically responsive miRNAs in the 3D strain microenvironment. The results suggested a significant reduction in the expression of miR-210-3p and miR-214-3p triggered by the 3D strain microenvironment in old-JBMSCs. Bioinformatic analysis indicated that both miRNAs participate in the regulation of critical pathways of aging and cellular senescence. Taken together, this study demonstrated that the 3D strain microenvironment efficiently rescued the cellular senescence of old-JBMSCs via modulating specific miRNAs, which provides a novel strategy for coordinating periodontal bone loss and regeneration of the elderly.

Vascular endothelial growth factor secretion and immunosuppression are distinct potency mechanisms of human bone marrow mesenchymal stromal cells.

Mesenchymal stromal cells (MSCs) are investigated as cellular therapeutics for inflammatory bowel diseases and associated perianal fistula, although consistent efficacy remains a concern. Determining host factors that modulate MSCs' potency including their secretion of angiogenic and wound-healing factors, immunosuppression, and anti-inflammatory properties are important determinants of their functionality. We investigated the mechanisms that regulate the secretion of angiogenic and wound-healing factors and immune suppression of human bone marrow MSCs. Secretory analysis of MSCs focusing on 18 angiogenic and wound-healing secretory molecules identified the most abundancy of vascular endothelial growth factor A (VEGF-A). MSC viability and secretion of other angiogenic factors are not dependent on VEGF-A secretion which exclude the autocrine role of VEGF-A on MSC's fitness. However, the combination of inflammatory cytokines IFNγ and TNFα reduces MSC's VEGF-A secretion. To identify the effect of intestinal microvasculature on MSCs' potency, coculture analysis was performed between human large intestine microvascular endothelial cells (HLMVECs) and human bone marrow-derived MSCs. HLMVECs do not attenuate MSCs' viability despite blocking their VEGF-A secretion. In addition, HLMVECs neither attenuate MSC's IFNγ mediated upregulation of immunosuppressive enzyme indoleamine 2,3-dioxygenase nor abrogate suppression of T-cell proliferation despite the attenuation of VEGF-A secretion. We found that HLMVECs express copious amounts of endothelial nitric oxide synthase and mechanistic analysis showed that pharmacological blocking reverses HLMVEC-mediated attenuation of MSC's VEGF-A secretion. Together these results suggest that secretion of VEGF-A and immunosuppression are separable functions of MSCs which are regulated by distinct mechanisms in the host.

Long noncoding RNA UCA1 promotes the chondrogenic differentiation of human bone marrow mesenchymal stem cells via regulating PARP1 ubiquitination.

Bone marrow mesenchymal stem cells (BMSCs) possess the potential to differentiate into cartilage cells. Long noncoding RNA (lncRNAs) UCA1 has been confirmed to improve the chondrogenic differentiation of marrow mesenchymal stem cells (MSCs). Herein, we further investigated the effects and underlying mechanisms in these processes. the expression of UCA1 was positively associated with chondrogenic differentiation and the knockdown of UCA1 has been shown to attenuate the expression of chondrogenic markers. RNA pull down assay and RNA immunoprecipitation showed that UCA1 could directly bind to PARP1 protein. UCA1 could improve PARP1 protein via facilitating USP9X-mediated PARP1 deubiquitination. Then these processes stimulated the NF-κB signaling pathway. In addition, PARP1 was declined in UCA1 knockdown cells, and silencing of PARP1 could diminishes the increasing effects of UCA1 on the chondrogenic differentiation from MSCs and signaling pathway activation. Collectively, these outcomes suggest that UCA1 could act as a mediator of PARP1 protein ubiquitination and develop the chondrogenic differentiation of MSCs.

Omaveloxolone ameliorates glucocorticoid-induced osteonecrosis of the femoral head by promoting osteogenesis and angiogenesis

Steroid (glucocorticoid)-induced necrosis of the femoral head (SONFH) represents a prevalent, progressive, and challenging bone and joint disease characterized by diminished osteogenesis and angiogenesis. Omaveloxolone (OMA), a semi-synthetic oleanocarpane triterpenoid with antioxidant, anti-inflammatory, and osteogenic properties, emerges as a potential therapeutic agent for SONFH. This study investigates the therapeutic impact of OMA on SONFH and elucidates its underlying mechanism. The in vitro environment of SONFH cells was simulated by inducing human bone marrow mesenchymal stem cells (hBMSCs) and human umbilical vein endothelial cells (HUVECs) using dexamethasone (DEX).Various assays, including CCK-8, alizarin red staining, Western blot, qPCR, immunofluorescence, flow cytometry, and TUNNEL, were employed to assess cell viability, STING/NF-κB signaling pathway-related proteins, hBMSCs osteogenesis, HUVECs migration, angiogenesis, and apoptosis. The results demonstrate that OMA promotes DEX-induced osteogenesis, HUVECs migration, angiogenesis, and anti-apoptosis in hBMSCs by inhibiting the STING/NF-κB signaling pathway. This experimental evidence underscores the potential of OMA in regulating DEX-induced osteogenesis, HUVECs migration, angiogenesis, and anti-apoptosis in hBMSCs through the STING/NF-κB pathway, thereby offering a promising avenue for improving the progression of SONFH.

Chaperone-mediated autophagy protects the bone formation from excessive inflammation through PI3K/AKT/GSK3β/β-catenin pathway.

Multiple regulatory mechanisms are in place to ensure the normal processes of bone metabolism, encompassing both bone formation and absorption. This study has identified chaperone-mediated autophagy (CMA) as a critical regulator that safeguards bone formation from the detrimental effects of excessive inflammation. By silencing LAMP2A or HSCA8, we observed a hindrance in the osteoblast differentiation of human bone marrow mesenchymal stem cells (hBMSCs) invitro. To further elucidate the role of LAMP2A, we generated LAMP2A gene knockdown and overexpression of mouse BMSCs (mBMSCs) using adenovirus. Our results showed that LAMP2A knockdown led to a decrease in osteogenic-specific proteins, while LAMP2A overexpression favored the osteogenesis of mBMSCs. Notably, active-β-catenin levels were upregulated by LAMP2A overexpression. Furthermore, we found that LAMP2A overexpression effectively protected the osteogenesis of mBMSCs from TNF-α, through the PI3K/AKT/GSK3β/β-catenin pathway. Additionally, LAMP2A overexpression significantly inhibited osteoclast hyperactivity induced by TNF-α. Finally, in a murine bone defect model, we demonstrated that controlled release of LAMP2A overexpression adenovirus by alginate sodium capsule efficiently protected bone healing from inflammation, as confirmed by imaging and histological analyses. Collectively, our findings suggest that enhancing CMA has the potential to safeguard bone formation while mitigating hyperactivity in bone absorption.

A novel miR-466l-3p/FGF23 axis promotes osteogenic differentiation of human bone marrow mesenchymal stem cells

BackgroundMicroRNAs (miRNAs) regulate osteogenic differentiation processes and influence the development of osteoporosis (OP). This study aimed to investigate the potential role of miR-466 l-3p in OP. MethodsThe expression levels of miR-466 l-3p and fibroblast growth factor 23 (FGF23) were quantified in the trabeculae of the femoral neck of 40 individuals with or without OP using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The impact of miR-466 l-3p or FGF23 expression on cell proliferation and the expression levels of runt-related transcription factor 2 (RUNX2), type I collagen (Col1), osteocalcin (OCN), osterix (OSX) and dentin matrix protein 1 (DMP1) was quantified in human bone marrow mesenchymal stem cells (hBMSCs) overexpressing miR-466 l-3p. Furthermore, alkaline phosphatase (ALP) staining and alizarin red staining were performed to measure ALP activity and the levels of calcium deposition, respectively. In addition, bioinformatics analysis, luciferase reporter assays, and RNA pull-down assays were conducted to explore the molecular mechanisms underlying the effects of miR-466 l-3p and FGF23 in osteogenic differentiation of hBMSCs. ResultsThe expression levels of miR-466 l-3p were significantly lower in femoral neck trabeculae of patients with OP than in the control cohort, whereas FGF23 levels exhibited the opposite trend. Furthermore, miR-466 l-3p levels were upregulated and FGF23 levels were downregulated in hBMSCs during osteogenic differentiation. Moreover, the high miR-466 l-3p expression enhanced the mRNA expression of RUNX2, Col1, OCN, OSX and DMP1, as well as cell proliferation, ALP activity, and calcium deposition in hBMSCs. FGF23 was found to be a direct target of miR-466 l-3p. FGF23 overexpression downregulated the expression of osteoblast markers and inhibited the osteogenic differentiation induced by miR-466 l-3p overexpression. qRT-PCR and Western blot assays showed that miR-466 l-3p overexpression decreased the expression levels of mRNAs and proteins associated with the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway, whereas FGF23 upregulation exhibited the opposite trend. ConclusionIn conclusion, these findings suggest that miR-466 l-3p enhances the osteogenic differentiation of hBMSCs by suppressing FGF23 expression, ultimately preventing OP.

Head-to-head comparison of relevant cell sources of small extracellular vesicles for cardiac repair: Superiority of embryonic stem cells.

Small extracellular vesicles (sEV) derived from various cell sources have been demonstrated to enhance cardiac function in preclinical models of myocardial infarction (MI). The aim of this study was to compare different sources of sEV for cardiac repair and determine the most effective one, which nowadays remains limited. We comprehensively assessed the efficacy of sEV obtained from human primary bone marrow mesenchymal stromal cells (BM-MSC), human immortalized MSC (hTERT-MSC), human embryonic stem cells (ESC), ESC-derived cardiac progenitor cells (CPC), human ESC-derived cardiomyocytes (CM), and human primary ventricular cardiac fibroblasts (VCF), in in vitro models of cardiac repair. ESC-derived sEV (ESC-sEV) exhibited the best pro-angiogenic and anti-fibrotic effects in vitro. Then, we evaluated the functionality of the sEV with the most promising performances in vitro, in a murine model of MI-reperfusion injury (IRI) and analysed their RNA and protein compositions. In vivo, ESC-sEV provided the most favourable outcome after MI by reducing adverse cardiac remodelling through down-regulating fibrosis and increasing angiogenesis. Furthermore, transcriptomic, and proteomic characterizations of sEV derived from hTERT-MSC, ESC, and CPC revealed factors in ESC-sEV that potentially drove the observed functions. In conclusion, ESC-sEV holds great promise as a cell-free treatment for promoting cardiac repair following MI.

Promoting neurogenesis in human bone marrow mesenchymal stem cells: An in vitro study

Promoting neurogenesis in human bone marrow mesenchymal stem cells: An in vitro study