Bone Marrow Mesenchymal Stem Cells Research Articles

MicroRNA-124a promoted the differentiation of bone marrow mesenchymal stem cells into neurons through Notch signal pathway

This study investigated the possible mechanisms of microRNA-124a on the differentiation of bone marrow mesenchymal stem cells (BMSCs) and its underlying mechanism. β-Thiol ethanol induced Notch1 mRNA expression, microRNA-124a inhibitor reduced the effects of β-thiol ethanol on Notch1 mRNA expression in BMSCs. Baicalin induced Hes1 mRNA expression, and microRNA-124a inhibitor reduced the effects of baicalin on Hes1 mRNA expression in BMSCs. Si-Notch1 suppressed Hes1 mRNA expression in BMSCs. Baicalin increased the effects of Notch1 on Hes1 mRNA expression in BMSCs. Si-Notch1 increased cell growth of BMSCs. Baicalin reduced the effects of si-Notch1 on cell growth and the differentiation of BMSCs. We demonstrated that microRNA-124a promoted the differentiation of BMSCs into neurons through Notch/Hes1 signal pathway.

Combined Effects of Cyclic Hypoxic and Mechanical Stimuli on Human Bone Marrow Mesenchymal Stem Cell Differentiation: A New Approach to the Treatment of Bone Loss.

Background: The prevention and treatment of bone loss and osteoporotic fractures is a public health challenge. Combined with normobaric hypoxia, whole-body vibration has a high clinic potential in bone health and body composition. The effect of this therapy may be mediated by its action on bone marrow mesenchymal stem cells (MSCs). Objectives: Evaluate the effects of cyclic low-vibration stimuli and/or hypoxia on bone marrow-derived human MSC differentiation. Methods: MSCs were exposed four days per week, two hours/day, to hypoxia (3% O2) and/or vibration before they were induced to differentiate or during differentiation into osteoblasts or adipocytes. Gene and protein expression of osteoblastic, adipogenic, and cytoskeletal markers were studied, as well as extracellular matrix mineralization and lipid accumulation. Results: early osteoblastic markers increased in undifferentiated MSCs, pretreated in hypoxia and vibration. This pretreatment also increased mRNA levels of osteoblastic genes and beta-catenin protein in the early stages of differentiation into osteoblasts without increasing mineralization. When MSCs were exposed to vibration under hypoxia or normoxia during osteoblastic differentiation, mineralization increased with respect to cultures without vibrational stimuli. In MSCs differentiated into adipocytes, both in those pretreated as well as exposed to different conditions during differentiation, lipid formation decreased. Changes in adipogenic gene expression and increased beta-catenin protein were observed in cultures treated during differentiation. Conclusions: Exposure to cyclic hypoxia in combination with low-intensity vibratory stimuli had positive effects on osteoblastic differentiation and negative ones on adipogenesis of bone marrow-derived MSCs. These results suggest that in elderly or frail people with difficulty performing physical activity, exposure to normobaric cyclic hypoxia and low-density vibratory stimuli could improve bone metabolism and health.

Sequential release of vancomycin and BMP-2 from chitosan/nano-hydroxyapatite thermosensitive hydrogel for the treatment of chronic osteomyelitis

In this study, we developed scaffolds materials with microspheres to form a double sustained release system.Chitosan/nano-hydroxyapatite (CS-HA) was used as a drug carrier to construct a sustained-release system for Bone morphogenetic protein-2(BMP-2) and Vancomycin (VAN). Furthermore, VAN and BMP-2 loaded microspheres (Ms) were prepared by the emulsion ultrasonic method.The resultant composites were characterized by Scanning electron microscope (SEM), compressive strength, porosity, and biodegradation. The characterization results showed uniform porous and rough surface, enhanced thermal stability, and highest compressive strength ((1.912 ± 0.012) Kpa, the surface of the two microspheres was slightly folded and showed a regular spherical shape.The loading rate of BMP-2 was (59.611 × 10-4 ± 0.023 × 10-4)% and the encapsulation rate was (6.022 ± 0.005)%. The release rate of vancomycin and BMP-2 was 57.194% and 12.968% respectively. Osteogenic differentiation of Bone marrow mesenchymal stem cells (BMSCs) was confirmed by alkaline phosphatase quantification. The deposition of late osteogenic markers (calcium phosphates) detected by Alizarin red, which indicated extracellular matrix mineralization. The results showed that BMP-2/VAN in CS-HA hydrogel successfully achieved the sequential release of the double drugs, which could benefit bone regeneration.

Research Progress on the SDF-1/CXCR4 Axis in Cartilage Injury

The chemokine CXCL12, also known as stromal cell-derived factor 1 (SDF-1), is a small pro-inflammatory chemokine that primarily binds to CXC receptor 4 (CXCR4; CD184), serving as a major regulatory factor for cell transport and adhesion. When SDF-1 binds to CXCR4, it triggers intracellular signaling through several pathways that initiate processes such as chemotaxis, cell survival, proliferation, calcium influx, and gene transcription. The SDF-1/CXCR4 axis plays a crucial role in the development of bone marrow stem cells and the process of tissue regeneration. Repairing cartilage tissue necessitates a sufficient number of chondrocytes, making bone marrow mesenchymal stem cells particularly suitable for this purpose. This signaling pathway is essential for cartilage injury repair. It promotes stem cell migration and localization, regulates cell proliferation and differentiation, and inhibits inflammatory responses. This article reviews the current research advancements related to the SDF-1/CXCR4 axis in cartilage tissue repair.

Injectable, oxygen-releasing, thermosensitive hydrogel promotes vascularized bone formation with prolonged oxygen delivery and improved osteoinductivity

The failure or delay in healing of critical bone defects is primarily due to early local anoxic conditions and reduced osteogenic activity. In this research, we integrated calcium peroxide (CPO) embedded polycaprolactone (PCL) microspheres and osteoinductive nanoparticles (Hydroxyapatite/Laponite) into a thermosensitive hydrogel (Pluronic F127), thereby formulating an injectable oxygen-releasing osteogenic thermosensitive hydrogel. Notably, the oxygen-releasing microspheres (ORMs) within the composite hydrogel provide stable oxygen release for up to 21 days, ensuring the survival, migration, and bioactivity of both mesenchymal stem cells and endothelial cells under anoxic conditions. Additionally, the composite hydrogel significantly augments the osteogenic potential of bone marrow mesenchymal stem cells by providing a biomimetic microenvironment with the incorporation of nano-hydroxyapatite/laponite. Ultimately, the injectable composite hydrogel successfully stimulated bone regeneration within a cranial defect in a rat model after 8 weeks, with enhanced vascularization and bone quality. The engineered hydrogel provides a minimally invasive approach to stimulate bone regeneration with a sustained oxygen supply and osteogenic microenvironment provision, underlining its potential for treating critical bone defects.

Olig2+ single-colony-derived cranial bone-marrow mesenchymal stem cells achieve improved regeneration in a cuprizone-induced demyelination mouse model.

Oligodendrocytes are the myelinating cells of the central nervous system. Brain injury and neurodegenerative disease often lead to oligodendrocyte death and subsequent demyelination-related pathological changes, resulting in neurological defects and cognitive impairment (Spaas et al., 2021; Zhang J et al., 2022). Multiple sclerosis (MS) is a major demyelinating disease of the central nervous system. The pathology of MS is characterized by the loss of myelin, oligodendrocytes, and axons in the brain, brain stem, and spinal cord, as well as by white matter lesions (Lassmann et al., 2007). Unfortunately, no definitive cure for MS has been developed. Immunomodulatory and anti-inflammatory drugs are effective in the relapsing-remitting phase of MS because they reduce the frequency of relapses and the formation of inflammatory lesions; however, they do not alter the course of progressive MS and are insufficient to cure chronic neurological dysfunction (Xiao et al., 2015; Zhang et al., 2021). The treatment outcome is even worse for MS patients with primary and secondary progressions. Mesenchymal stem cells (MSCs) are stromal cells that can self-renew and exhibit multilineage differentiation. MSCs are easy to expand in vitro and exhibit low immunogenicity, no tumorigenic risks, and ethical controversies, making them a promising candidate for regenerative medicine (Zhang L et al., 2022; Xu et al., 2023). Many studies have confirmed the neural differentiation potential of MSCs under certain conditions, making them a prime candidate for treating neurodegenerative diseases (Jang et al., 2010; Yan et al., 2013). The present study investigated the effects of cranial bone-marrow mesenchymal stem cells (cBMMSCs) and oligodendrocyte-specific protein 2-positive (Olig2+) single-colony-derived cBMMSC (sc-cBMMSC), isolated in our previous work (Yang et al., 2022), in a central nervous system demyelination mouse model.

MiR-223-3p-loaded Exosomes Derived from Bone Marrow Mesenchymal Stem Cells Ameliorate Mouse Myocardial Infarction Injury through Inhibiting NLRP3 Inflammasome Activation

MiR-223-3p-loaded Exosomes Derived from Bone Marrow Mesenchymal Stem Cells Ameliorate Mouse Myocardial Infarction Injury through Inhibiting NLRP3 Inflammasome Activation

Osteogenic and osteoclastic differentiation by control release of adenosine within PEI/HA/Collagen composite coatings

In virtue of the rapid metabolism and short half-life of adenosine (AD) in the human body, it is highly desired to explore new adenosine delivery system with controlled and steady release capacity. In this study, composite coatings consisting of polyethyleneimine (PEI), hyaluronic acid (HA) and collagen type I (COL-1) on titanium substrate surface are developed by layer-by-layer self-assembly technique, in which different concentrations of AD are encapsulated. In-vitro release study demonstrated a steady and sustained release of AD from the composite coating system. Adenosine within composite coatings depicted a concentration-dependent regulatory effect on the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and osteoclastic differentiation of mouse leukemia cells of monocyte macrophage (RAW264.7) cells. All of these coatings exhibited good cell viability and promoted osteoblast cell proliferation. Among various composite coatings, the optimized coating specimen with loading of 65 μg AD (AD2) exhibits the best osteoconductive and osteoinductive activities with significantly enhanced osteoblast-associated gene expressions, and increased alkaline phosphatase (ALP) activity and calcium deposits. On the other hand, AD2 specimen shows the activity of inhibiting osteoclast differentiation and osteobclast-associated gene expressions as well as suppressing tartrate-resistant acid phosphatase (TRAP) activity. The superior performance of AD/PEI/HA/COL composite coatings indicated that this coating system could be useful for bone tissue engineering.

Functionalized 3D-printed GelMA/Laponite hydrogel scaffold promotes BMSCs recruitment through osteoimmunomodulatory enhance osteogenic via AMPK/mTOR signaling pathway

The migration and differentiation of bone marrow mesenchymal stem cells (BMSCs) play crucial roles in bone repair processes. However, conventional scaffolds often lack of effectively inducing and recruiting BMSCs. In our study, we present a novel approach by introducing a 3D-bioprinted scaffold composed of hydrogels, with the addition of laponite to the GelMA solution, aimed at enhancing scaffold performance. Both in vivo and in vitro experiments have confirmed the outstanding biocompatibility of the scaffold. Furthermore, for the first time, Apt19s has been chemically modified onto the surface of the hydrogel scaffold, resulting in a remarkable enhancement in the migration and adhesion of BMSCs. Moreover, the scaffold has demonstrated robust osteogenic differentiation capability in both in vivo and in vitro environments. Additionally, the hydrogel scaffold has shown the ability to induce the polarization of macrophages from M1 to M2, thereby facilitating the osteogenic differentiation of BMSCs via the bone immune pathway. Through RNA-seq analysis, it has been revealed that macrophages regulate the osteogenic differentiation of BMSCs through the AMPK/mTOR signaling pathway. In summary, the functionalized GelMA/Laponite scaffold offers a cost-effective approach for tailored in situ bone regeneration.

Comparative investigation of exosome extraction from rat bone marrow mesenchymal stem cells using three different methodologies

AbstractExosomes have been identified as crucial mediators in numerous physiological and pathological processes, emerging as a focal point of scientific inquiry. This study aims to compare three methods for isolating exosomes from rat bone marrow mesenchymal stem cells: ultracentrifugation (UC), ultrafast separation system (EXODUS), and commercial precipitation kit (EXO‐kit). First, the investigation compared exosomal morphology, particle size distribution, and expression of marker proteins. Subsequently, the RNA content, protein concentration, and purity of exosomes were evaluated. Finally, the impact of these exosomes on cellular metabolic viability and migration capacity was assessed. Results indicated that exosomes exhibited spherical or elliptical membrane structures, and most of the exosomes extracted by the three methods were in the range of 30to 200 nm. UC‐extracted exosomes demonstrated the least impurities and clearest background, followed by EXODUS‐extracted exosomes, and lastly EXO‐kit‐extracted exosomes. The EXO‐kit‐extracted exosomes yielded the highest RNA and protein content, whereas those isolated through UC exhibited superior purity. Furthermore, exosomes extracted from EXODUS and EXO‐kit methods effectively enhanced the metabolic viability and migratory ability of osteoblast precursor cells compared to UC‐extracted exosomes. In conclusion, each of the three methodologies presents advantages and limitations. Therefore, the selection of an appropriate exosome extraction technique should be based on specific experimental objectives and requirements.

A Network Meta-Analysis of Randomized Controlled Trials on the Comparative Efficacy of Stem Cells Therapy for Diabetic Foot Ulcer Healing

Stem cell therapy in diabetic foot ulcer has emerged as a promising treatment option to promote ulcer healing. This network meta-analysis was undertaken to evaluate how they compete with each other and their ranking with respect to chances of ulcer healing. A systematic search strategy to retrieve data from five databases, were used to identify potential studies. Randomized controlled trial or clinical controlled trial, published in English, using any type of stem cells as intervention in individuals aged over 18 years diagnosed with diabetic foot ulcers were included. This network meta-analysis was performed using frequentist method using R version 4.2.1. Eighteen clinical trials were included in the study which included 13 interventions. The study found that most of the stem cells were significantly promoting ulcer healing chances with human viable wound matrix (hVWM) [RR 2.91; CI: 1.28, 6.64], peripheral blood mononuclear cells (PBMNC) [RR 2.35; CI: 1.21, 4.55], bone marrow mesenchymal stem cells (BMMSCs) [RR 2.20; CI: 1.34, 3.60], were top three stem cell options among all. P score also suggested the same. Risk of bias study suggested that there was “some concern or “high risk’’ among majority of studies. It is evident from this study that bone marrow mononuclear cells were found to be most effective in wound healing in cases of diabetic foot ulcer in that order. Though there was no significant difference between these and more studies were required to ascertain whether they differ in term of efficacy for the clinical outcome of ulcer healing.

Human decidual mesenchymal stem cells obtained from early pregnancy attenuate bleomycin-induced lung fibrosis by inhibiting inflammation and apoptosis

BackgroundDecidual mesenchymal stem cells (DMSCs) are easily obtained and exhibit strong anti-inflammatory and anti-apoptotic effects. Compared with bone marrow mesenchymal stem cells (BMSCs), their role in cell transplantation after idiopathic pulmonary fibrosis remains unclear. We investigated whether the transplantation of BMSCs and DMSCs could alleviate pulmonary inflammation and fibrosis in a bleomycin-induced mouse model of pulmonary fibrosis. MethodsBMSCs and DMSCs were derived from healthy donors. The anti-inflammatory and anti-apoptotic effects on both cell types were evaluated in vitro. The function of DMSCs in MLE-12 cells and mouse lung fibroblasts was examined using additional transwell coculture experiments in vitro. Twenty-one days after MSC transplantation, we examined the inflammatory factors in the serum and bronchoalveolar lavage fluid, collagen content, pathology, fibrotic area, lung function, and micro-computed tomography of the lung tissue. ResultsDMSCs exhibited better anti-inflammatory and anti-apoptotic effects than BMSCs on MLE-12 cells in vitro. In addition, DMSCs inhibited tumor growth factor β-dependent epithelial-mesenchymal transition in MLE-12 cells and attenuated mouse lung fibroblasts fibrosis. Furthermore, transplantation of DMSCs in the mouse idiopathic pulmonary fibrosis model significantly attenuated pulmonary inflammation and lung fibrosis compared with BMSCs transplantation. ConclusionsDMSCs exhibited better efficacy in improving pulmonary inflammation and lung fibrosis than BMSCs. Thus, DMSCs are a potential therapeutic target for pulmonary fibrosis.

Engineering Thermoresponsive Poly(N-isopropylacrylamide)-Based Films with Enhanced Stability and Reusability for Efficient Bone Marrow Mesenchymal Stem Cell Culture and Harvesting.

Poly(N-isopropylacrylamide) (PNIPAM) offers a promising platform for non-invasive and gentle cell detachment. However, conventional PNIPAM-based substrates often suffer from limitations including limited stability and reduced reusability, which hinder their widespread adoption in biomedical applications. In this study, PNIPAM copolymer films were formed on the surfaces of glass slides or silicon wafers using a two-step film-forming method involving coating and grafting. Subsequently, a comprehensive analysis of the films' surface wettability, topography, and thickness was conducted using a variety of techniques, including contact angle analysis, atomic force microscopy (AFM), and ellipsometric measurements. Bone marrow mesenchymal stem cells (BMMSCs) were then seeded onto PNIPAM copolymer films prepared from different copolymer solution concentrations, ranging from 0.2 to 10 mg·mL-1, to select the optimal culture substrate that allowed for good cell growth at 37 °C and effective cell detachment through temperature reduction. Furthermore, the stability and reusability of the optimal copolymer films were assessed. Finally, AFM and X-ray photoelectron spectroscopy (XPS) were employed to examine the surface morphology and elemental composition of the copolymer films after two rounds of BMMSC adhesion and detachment. The findings revealed that the surface properties and overall characteristics of PNIPAM copolymer films varied significantly with the solution concentration. Based on the selection criteria, the copolymer films derived from 1 mg·mL-1 solution were identified as the optimal culture substrates for BMMSCs. After two rounds of cellular adhesion and detachment, some proteins remained on the film surfaces, acting as a foundation for subsequent cellular re-adhesion and growth, thereby implicitly corroborating the practicability and reusability of the copolymer films. This study not only introduces a stable and efficient platform for stem cell culture and harvesting but also represents a significant advance in the fabrication of smart materials tailored for biomedical applications.

Effect of AML-exosomes on the cellular and molecular properties of bone marrow mesenchymal stromal cells: Expression of JAK/STAT signaling genes

Purpose of studyDespite the various therapeutic options introduced for AML treatment, therapy resistance and relapse are still the main obstacles. It is well known that alterations in the bone marrow microenvironment (BMM) play a crucial role in leukemia growth and the treatment failure of AML. Evidence shows that exosomes alter the components of BMM in a way that support leukemia survival, leading to chemoresistance. In this study, we evaluated the effect of AML exosomes on the biological functions of human bone marrow mesenchymal stromal cells (h BM-MSCs), especially alteration in the expression of the JAK/STAT signaling genes, as a leukemia-favoring pathway. MethodExosomes were isolated from the HL-60 cell line and characterized using flow cytometry, Transmission Electron Microscopy (TEM), and Dynamic Light Scattering (DLS) technique. The exosome protein content was assessed using a bicinchoninic acid (BCA) protein assay kit in order to determine the concentration of exosomes. Subsequently, MSCs were treated with varying concentrations of AML exosomes, and data was obtained using MTT, cell cycle, apoptosis, and ki67 assays. Additionally, gene expression analysis was conducted through qRT-PCR. ResultAML exosomes regulated the viability and survival of MSCs in a concentration-dependent manner. The qRT-PCR data revealed that treatment with AML exosomes at a concentration of 50 μg/mL led to a significant upregulation of JAK2, STAT3, and STAT5 genes in MSCs. ConclusionBecause the JAK/STAT signaling pathway has been shown to play a role in the proliferation and survival of leukemic cells, our results suggest that AML exosomes stimulate MSCs to activate this pathway. This activation may impede AML cell apoptosis, potentially leading to chemoresistance and relapse.

Multilayer Gelatin-Supported BMP-9 Coating Promotes Osteointegration and Neo-Bone Formation at the n-CDHA/PAA Composite Biomaterial-Bone Interface.

The development of biomaterials capable of accelerating bone wound repair is a critical focus in bone tissue engineering. This study aims to evaluate the osteointegration and bone regeneration potential of a novel multilayer gelatin-supported Bone Morphogenetic Protein 9 (BMP-9) coated nano-calcium-deficient hydroxyapatite/poly-amino acid (n-CDHA/PAA) composite biomaterials, focusing on the material-bone interface, and putting forward a new direction for the research on the interface between the coating material and bone. The BMP-9 recombinant adenovirus (Adenovirus (Ad)-BMP-9/Bone Marrow Mesenchymal Stem Cells (BMSc)) was produced by transfecting BMSc and supported using gelatin (Ad-BMP-9/BMSc/Gelatin (GT). Multilayer Ad-BMP-9/BMSc/GT coated nano-calcium deficient hydroxyapatite/polyamino acid (n-CDHA/PAA) composite biomaterials were then prepared and co-cultured with MG63 cells for 10 days, with biocompatibility assessed through microscopy, Cell Counting Kit-8 (CCK-8), and alkaline phosphatase (ALP) assays. Subsequently, multilayer Ad-BMP-9/BMSc/GT coated n-CDHA/PAA composite biomaterial screws were fabricated, and the adhesion of the coating to the substrate was observed using scanning electron microscopy (SEM). In vivo studies were conducted using a New Zealand White rabbit intercondylar femoral fracture model. The experimental group was fixed with screws featuring multilayer Ad-BMP-9/BMSc/GT coatings, while the control groups used medical metal screws and n-CDHA/PAA composite biomaterial screws. Fracture healing was monitored at 1, 4, 12, and 24 weeks, respectively, using X-ray observation, Micro-CT imaging, and SEM. Integration at the material-bone interface and the condition of neo-tissue were assessed through these imaging techniques. The Ad-BMP-9/GT coating significantly enhanced MG63 cell adhesion, proliferation, and differentiation, while increasing BMP-9 expression in vitro. In vivo studies using a rabbit femoral fracture model confirmed the biocompatibility and osteointegration potential of the multilayer Ad-BMP-9/BMSc/GT coated n-CDHA/PAA composite biomaterial screws. Compared to control groups (medical metal screws and n-CDHA/PAA composite biomaterial screws), this material demonstrated faster fracture healing, stronger osteointegration, and facilitated new bone tissue formation with increased calcium deposition at the material-bone interface. The multilayer GT-supported BMP-9 coated n-CDHA/PAA composite biomaterials have demonstrated favorable osteogenic cell interface performance, both in vitro and in vivo. This study provides a foundation for developing innovative bone repair materials, holding promise for significant advancements in clinical applications.

Lycium barbarum glycopeptide reduces bone loss caused by exosomes derived from human gingival fibroblasts with radiation exposure

To explore the protective effect of Lycium barbanun glycopeptide (LbGP) against osteogenic inhibition induced by exosomes derived from human gingival fibroblasts (HGFs) exposed to radiation. Cultured HGFs with or without LbGP pretreatment were exposed to 8 Gy X-ray radiation, and the changes in cell apoptosis, senescence and α-SMA level were detected using RT-qPCR, Western blotting and β-galactosidase staining. The exosomes secreted by the treated cells were extracted, and after identification by electron microscopy, particle size analysis and Western blotting, the exosomes were added into primary cultured bone mesenchymal stem cells (BMSCs), and osteoclast activity and osteogenesis in the cell cultures were detected by Trap staining, Alizarin red staining, ALP staining, RT-qPCR and Western blotting. In cultured HGFs, X-ray radiation significantly increased the percentage of senescent cells, which was obviously lowered by LbGP treatment. X-ray radiation significantly reduced Bcl-2/Bax ratio and increased α -SMA expression in HGFs, and these changes were significantly suppressed by LbGP pretreatment. In rat BMSCs, incubation with the exosomes derived from HGFs with radiation exposure caused a significant increase of osteoclasts, reduced calcium nodules and lowered alkaline phosphatase expression in the cells; The opposite changes were observed in the cells treated with exosomes from LbGPpretreated HGFs, which also significantly increased the cellular expressions of the osteogenic genes (BMP2, ALP, and RUNX2) and proteins (ALP and RUNX2) as compared with the exosomes from irradiated HGFs. LbGP can effectively inhibit osteoclast activity and promote osteogenesis by acting on exosomes secreted by irradiated HGFs, suggesting its potential value for treatment of osteoradionecrosis of the jaw.

A multifunctional composite scaffold responds to microenvironment and guides osteogenesis for the repair of infected bone defects

Treating bone defect concomitant with microbial infection poses a formidable clinical challenge. Addressing this dilemma necessitates the implementation of biomaterials exhibiting dual capabilities in anti-bacteria and bone regeneration. Of particular significance is the altered microenvironment observed in infected bones, characterized by acidity, inflammation, and an abundance of reactive oxygen species (ROS). These conditions, while challenging, present an opportunity for therapeutic intervention in the context of contaminated bone defects. In this study, we developed an oriented composite scaffold containing copper-coated manganese dioxide (MnO2) nanoparticles loaded with parathyroid hormone (PMPC/Gelatin). The characteristics of these scaffolds were meticulously evaluated and confirmed the high sensitivity to H+, responsive drug release and ROS elimination. In vitro antibacterial analysis underscored the remarkable ability of PMPC/Gelatin scaffolds to substantially suppressed bacterial proliferation and colony formation. Furthermore, this nontoxic material demonstrated efficacy in mitigating ROS levels, thereby fostering osteogenic differentiation of bone marrow mesenchymal stem cells and enhancing angiogenic ability. Subsequently, the infected models of bone defects in rat skulls were established to investigate the effects of composite scaffolds on anti-bacteria and bone formation in vivo. The PMPC/Gelatin treatment exhibited excellent antibacterial activity, coupled with enhanced vascularization and osteogenesis at the defect sites. These compelling findings affirm that the PMPC/Gelatin composite scaffold represents a promising avenue for anti-bacteria and bone regeneration.

Injectable decellularized Wharton's jelly hydrogel containing CD56+ umbilical cord mesenchymal stem cell-derived exosomes for meniscus tear healing and cartilage protection

Traditional meniscectomy or suture for meniscal tear usually leads to failed self-healing, cartilage degeneration and worse osteoarthritis. The strategies that facilitate the healing process of torn meniscus and safeguard knee cartilage against degeneration will be promising for clinical therapy. The CD56+ umbilical cord mesenchymal stem cells (UCSCs) (CD56+UCSCs) were sorted from Wharton's jelly using flow cytometer. Then, the modified decellularized Wharton's Jelly hydrogel (DWJH) was combined with isolated CD56+Exos from CD56+UCSCs to fabricate DWJH/CD56+Exos. The in vitro studies were performed to characterize the DWJ (decellularized Wharton's Jelly). The injectability and rheological properties were assessed by shear rate and frequency sweep analysis. The biocompatibility and chondrogenic differentiation inducibility of DWJH/CD56+Exos were performed on human bone marrow mesenchymal stem cells (hBMSCs) and RAW 264.7 cells. The release dynamics was evaluated in vitro and in vivo experiments. As for the in vivo experiments, the operated rats that subjected to a 2 mm full-thickness longitudinal tear in right medial anterior meniscus were injected a single dose of DWJH/CD56+Exos. At 4 and 8 weeks postoperatively, torn meniscus healing and articular cartilage degeneration were evaluated by hematoxylin and eosin (H&E), safranin O/fast green (SO&FG), and Sirius red staining. In in vitro experiments, the injectable DWJH/CD56+Exos demonstrated excellent biocompatibility, exosome releasing efficiency, injectable property and chondrogenic inducibility. The results of in vivo experiments revealed that DWJH/CD56+Exos degraded over time, promoted meniscal chondrogenesis, organized meniscal extracellular matrix remodeling, safeguard articular cartilage and inhibited secondary cartilage degeneration, which accelerated further facilitated torn meniscus healing. The novel injectable DWJH/CD56+Exos promoted meniscal tear healing by promoting meniscal chondrogenesis, safeguarding articular cartilage, and inhibiting secondary cartilage degeneration.

BMSCs-Derived Extracellular VesiclemiR-29a-3p Improved the Stability of Rat Myasthenia Gravis by Regulating Treg/Th17 Cells

ABSTRACT Introduction Myasthenia gravis (MG) is an autoimmune disorder. Microvesicle-derived miRNAs have been implicated in autoimmune diseases. However, the role of microvesicle-derived miR-29a-3p in MG remains poorly understood. This study aimed to investigate the therapeutic effect and mechanism of miR-29a-3p derived from stem cell microvesicles (MVs) on experimental autoimmune myasthenia gravis (EAMG) rats. Methods EAMG was induced in rats by injection of the subunit of the rat nicotinic anti-acetylcholine receptor (AChR) R97–116 peptide.Besides the control group, EAMG rats were randomly allocated into the EAMG model group, MV group, MV-NC-agomir group, and MV- miR-29a-3p-agomir group. Results Our results found that BMSCs-MV promoted miR-29a-3p expression in gastrocnemius of EAMG rats. Bone marrow mesenchymal stem cells (BMSCs) derived microvesicle miR-29a-3p improved the hanging ability and swimming time of EMGA rats and weakened the degree of muscle fiber atrophy. Furthermore, microvesicles from miR-29a-3p overexpressing BMSCs reduced the content of AchR-Ab in the serum of EAMG rats. BMSC-derived microvesicle miR-29a-3p further suppressed the expression of IFN-γ and enhanced the IL-4 and IL-10 in the serum of EAMG rats by restoring the Th17/Treg cells balance. Discussion BMSCs-derived microvesicle miR-29a-3p improved the stability of rat myasthenia gravis by regulating Treg/Th17 cells. It may be an effective treatment for MG.

Similarity-based metric analysis approach for predicting osteogenic differentiation correlation coefficients and discovering the novel osteogenic-related gene FOXA1 in BMSCs.

As a powerful tool, bioinformatics analysis is playing an increasingly important role in many fields. Osteogenic differentiation is a complex biological process involving the fine regulation of numerous genes and signaling pathways. Osteogenic differentiation-related genes are collected from the online databases. Then, we proposed two indexes Jaccard similarity and Sorensen-Dice similarity to measure the topological relevance of genes in the human PPI network. Furthermore, we selected three pathways involving osteoblast-related transcription factors, osteoblast differentiation, and RUNX2 regulation of osteoblast differentiation for investigation. Subsequently, we performed functional a enrichment analysis of these top-ranked genes to check whether these candidate genes identified by similarity-based metrics are enriched in some specific biological functions and states. we performed a permutation test to investigate the similarity score with four well-known osteogenic differentiation-related pathways including hedgehog signaling pathway, BMP signaling, ERK pathway, and Wnt signaling pathway to check whether these osteogenic differentiation-related pathways can be regulated by FOXA1. Lentiviral transfection was used to knockdown and overexpress gene FOXA1 in human bone mesenchymal stem cells (hBMSCs). Alkaline phosphatase (ALP) staining and Alizarin Red staining (ARS) were employed to investigate osteogenic differentiation of hBMSCs. After data collection, human PPI network involving 19,344 genes is included in our analysis. After simplifying, we used Jaccard and Sorensen-Dice similarity to identify osteogenic differentiation-related genes and integrated into a final similarity matrix. Furthermore, we calculated the sum of similarity scores with these osteogenic differentiation-related genes for each gene and found 337 osteogenic differentiation-related genes are involved in our analysis. We selected three pathways involving osteoblast-related transcription factors, osteoblast differentiation, and RUNX2 regulation of osteoblast differentiation for investigation and performed functional enrichment analysis of these top-ranked 50 genes. The results collectively demonstrate that these candidate genes can indeed capture osteogenic differentiation-related features of hBSMCs. According to the novel analyzing method, we found that these four pathways have significantly higher similarity with FOXA1 than random noise. Moreover, knockdown FOXA1 significantly increased the ALP activity and mineral deposits. Furthermore, overexpression of FOXA1 dramatically decreased the ALP activity and mineral deposits. In summary, this study showed that FOXA1 is a novel significant osteogenic differentiation-related transcription factor. Moreover, our study has tightly integrated bioinformatics analysis with biological knowledge, and developed a novel method for analyzing the osteogenic differentiation regulatory network.