OBJECTIVE: To Investigate the effects of lithocholic acid (LCA) on the balance between osteogenic and adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). METHODS: Twelve 10-week-old SPF C57BL/6J female mice were randomly divided into an experimental group (undergoing bilateral ovariectomy) and a control group (only removing the same volume of adipose tissue around the ovaries), with 6 mice in each group. The body mass was measured every week after operation. After 4 weeks post-surgery, the weight of mouse uterus was measured, femur specimens of the mice were taken for micro-CT scanning and three-dimensional reconstruction to analyze changes in bone mass. Tibia specimens were taken for HE staining to calculate the number and area of bone marrow adipocytes in the marrow cavity area. ELISA was used to detect the expression of bone turnover markers in the serum. Liver samples were subjected to real-time fluorescence quantitative PCR (RT-qPCR) to detect the expression of key genes related to bile acid metabolism, including cyp7a1, cyp7b1, cyp8b1, and cyp27a1. BMSCs were isolated by centrifugation from 2 C57BL/6J female mice (10-week-old). The third-generation cells were exposed to 0, 1, 10, and 100 μmol/L LCA, following which cell viability was evaluated using the cell counting kit 8 assay. Subsequently, alkaline phosphatase (ALP) staining and oil red O staining were conducted after 7 days of osteogenic and adipogenic induction. RT-qPCR was employed to analyze the expressions of osteogenic-related genes, namely ALP, Runt-related transcription factor 2 (Runx2), and osteocalcin (OCN), as well as adipogenic-related genes including Adiponectin (Adipoq), fatty acid binding protein 4 (FABP4), and peroxisome proliferator-activated receptor γ (PPARγ). RESULTS: Compared with the control group, the body mass of the mice in the experimental group increased, the uterus atrophied, the bone mass decreased, the bone marrow fat expanded, and the bone metabolism showed a high bone turnover state. RT-qPCR showed that the expressions of cyp7a1, cyp8b1, and cyp27a1, which were related to the key enzymes of bile acid metabolism in the liver, decreased significantly ( P<0.05), while the expression of cyp7b1 had no significant difference ( P>0.05). Intervention with LCA at concentrations of 1, 10, and 100 μmol/L did not demonstrate any apparent toxic effects on BMSCs. Furthermore, LCA inhibited the expressions of osteogenic-related genes (ALP, Runx2, and OCN) in a dose-dependent manner, resulting in a reduction in ALP staining positive area. Concurrently, LCA promoted the expressions of adipogenic-related genes (Adipoq, FABP4, and PPARγ), and an increase in oil red O staining positive area. CONCLUSION After menopause, the metabolism of bile acids is altered, and secondary bile acid LCA interferes with the balance of osteogenic and adipogenic differentiation of BMSCs, thereby affecting bone remodelling.
Female ; Mice ; Animals ; Core Binding Factor Alpha 1 Subunit/pharmacology* ; PPAR gamma/metabolism* ; Steroid 12-alpha-Hydroxylase/metabolism* ; Mice, Inbred C57BL ; Cell Differentiation ; Osteogenesis ; Mesenchymal Stem Cells ; Bile Acids and Salts/pharmacology* ; Bone Marrow Cells ; Cells, Cultured ; Azo Compounds

In recent years, mesenchymal stem cell (MSCs)-derived exosomes have attracted much attention in the field of tissue regeneration. Mesenchymal stem cell-derived exosomes are signaling molecules for communication among cells. They are characterized by natural targeting and low immunogenicity, and are mostly absorbed by cells through the paracrine pathway of mesenchymal stem cells. Moreover, they participate in the regulation and promotion of cell or tissue regeneration. As a scaffold material in regenerative medicine, hydrogel has good biocompatibility and degradability. Combining the two compounds can not only improve the retention time of exosomes at the lesion site, but also improve the dose of exosomes reaching the lesion site by in situ injection, and the therapeutic effect in the lesion area is significant and continuous. This paper summarizes the research results of the interaction of exocrine and hydrogel composite materials to promote tissue repair and regeneration, in order to facilitate research in the field of tissue regeneration in the future.
Hydrogels/metabolism* ; Exosomes/metabolism* ; Wound Healing ; Regenerative Medicine ; Mesenchymal Stem Cells/metabolism*

A triple-transgenic (tyrosine hydroxylase/dopamine decarboxylase/GTP cyclohydrolase 1, TH/DDC/GCH1) bone marrow mesenchymal stem cell line (BMSCs) capable of stably synthesizing dopamine (DA) transmitters were established to provide experimental evidence for the clinical treatment of Parkinson's disease (PD) by using this cell line. The DA-BMSCs cell line that could stably synthesize and secrete DA transmitters was established by using the triple transgenic recombinant lentivirus. The triple transgenes (TH/DDC/GCH1) expression in DA-BMSCs was detected using reverse transcription-polymerase chain reaction (RT-PCR), Western blotting, and immunofluorescence. Moreover, the secretion of DA was tested by enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography (HPLC). Chromosome G-banding analysis was used to detect the genetic stability of DA-BMSCs. Subsequently, the DA-BMSCs were stereotactically transplanted into the right medial forebrain bundle (MFB) of Parkinson's rat models to detect their survival and differentiation in the intracerebral microenvironment of PD rats. Apomorphine (APO)-induced rotation test was used to detect the improvement of motor dysfunction in PD rat models with cell transplantation. The TH, DDC and GCH1 were expressed stably and efficiently in the DA-BMSCs cell line, but not expressed in the normal rat BMSCs. The concentration of DA in the cell culture supernatant of the triple transgenic group (DA-BMSCs) and the LV-TH group was extremely significantly higher than that of the standard BMSCs control group (P < 0.000 1). After passage, DA-BMSCs stably produced DA. Karyotype G-banding analysis showed that the vast majority of DA-BMSCs maintained normal diploid karyotypes (94.5%). Moreover, after 4 weeks of transplantation into the brain of PD rats, DA-BMSCs significantly improved the movement disorder of PD rat models, survived in a large amount in the brain microenvironment, differentiated into TH-positive and GFAP-positive cells, and upregulated the DA level in the injured area of the brain. The triple-transgenic DA-BMSCs cell line that stably produced DA, survived in large numbers, and differentiated in the rat brain was successfully established, laying a foundation for the treatment of PD using engineered culture and transplantation of DA-BMSCs.
Rats ; Animals ; Dopamine ; Parkinson Disease/metabolism* ; Mesenchymal Stem Cells/metabolism* ; Cell Line ; Brain/metabolism* ; Cell Differentiation ; Mesenchymal Stem Cell Transplantation

OBJECTIVE: To investigate the regulatory effects of miR-26a-5p on the osteogenic differentiation of adipose-derived mesenchymal stem cells (ADSCs) by regulating cAMP response element binding protein 1 (CREB1). METHODS: The adipose tissues of four 3-4 weeks old female C57BL/6 mice were collected and the cells were isolated and cultured by digestion separation method. After morphological observation and identification by flow cytometry, the 3rd-generation cells were subjected to osteogenic differentiation induction. At 0, 3, 7, and 14 days after osteogenic differentiation induction, the calcium deposition was observed by alizarin red staining, ALP activity was detected, miR- 26a-5p and CREB1 mRNA expressions were examined by real-time fluorescence quantitative PCR, and CREB1 protein and its phosphorylation (phospho-CREB1, p-CREB1) level were measured by Western blot. After the binding sites between miR-26a-5p and CREB1 was predicted by the starBase database, HEK-293T cells were used to conduct a dual-luciferase reporter gene experiment to verify the targeting relationship (represented as luciferase activity after 48 hours of culture). Finally, miR-26a-p inhibitor (experimental group) and the corresponding negative control (control group) were transfected into ADSCs. Alizarin red staining, ALP activity, real-time fluorescent quantitative PCR (miR-26a-5p) and Western blot [CREB1, p-CREB1, Runt-related transcription factor 2 (RUNX2), and osteocalcin (OCN)] were performed at 7 and 14 days after osteogenic induction culture. RESULTS: The cultured cells were identified as ADSCs. With the prolongation of osteogenic induction culture, the number of calcified nodules and ALP activity significantly increased ( P<0.05). The relative expression of miR-26a-5p in the cells gradually decreased, while the relative expressions of CREB1 mRNA and protein, as well as the relative expression of p-CREB1 protein were increased. The differences were significant between 7, 14 days and 0 day ( P<0.05). There was no significant difference in p-CREB1/CREB1 between different time points ( P>0.05). The starBase database predicted that miR-26a-5p and CREB1 had targeted binding sequences, and the dual-luciferase reporter gene experiment revealed that overexpression of miR-26a-5p significantly suppressed CREB1 wild-type luciferase activity ( P<0.05). After 7 and 14 days of osteogenic induction, compared with the control group, the number of calcified nodules, ALP activity, and relative expressions of CREB1, p-CREB1, OCN, and RUNX2 proteins in the experimental group significantly increased ( P<0.05). There was no significant difference in p-CREB1/CREB1 between the two groups ( P>0.05). CONCLUSION Knocking down miR-26a-5p promoted the osteogenic differentiation of ADSCs by up-regulating CREB1 and its phosphorylation.
Animals ; Female ; Mice ; Cell Differentiation ; Cells, Cultured ; Core Binding Factor Alpha 1 Subunit/metabolism* ; Cyclic AMP Response Element-Binding Protein/metabolism* ; Mesenchymal Stem Cells ; Mice, Inbred C57BL ; MicroRNAs/metabolism* ; Osteocalcin/metabolism* ; Osteogenesis/genetics* ; RNA, Messenger/genetics*

Objective To investigate the effects of miR-877-3p on migration and apoptotic T lymphocytes of bone mesenchymal stem cells (BMSCs). Methods The model of osteoporosis induced by bilateral ovariectomy (OVX) and sham operation was established. At 8 weeks after operation, the bone parameters of the two groups were detected by micro-CT. The levels of monocyte chemotactic protein 1(MCP-1) in BMSCs were detected by ELISA. BMSC in OVX group and sham group were co-cultured with T lymphocytes, respectively. The migration ability of T lymphocytes in the two groups was observed by Transwell^TM assay with PKH26 staining and apoptosis of T lymphocytes were detected by flow cytometry. Reverse transcription PCR was used to detect the expression of miR-877-3p in BMSCs. miR-877-3p was overexpressed or down-regulated by cell transfection. The level of MCP-1 secreted by BMSCs in each group was detected by ELISA. The migration and apoptosis of T lymphocytes were detected by the above methods. Results The number of trabecular bone and bone mineral density in OVX group were lower than those in sham group. The levels of MCP-1 secretion, chemotactic and apoptotic T lymphocyte ability of BMSCs in OVX group were also lower than those in sham group. The expression level of miR-877-3p in BMSC in OVX group was higher than that in sham group. After overexpression of BMSC miR-877-3p, the levels of MCP-1 secreted from BMSCs, and apoptotic T lymphocytes decreased, while the results were opposite after down-regulation of miR-877-3p. Conclusion miR-877-3p may be one of the causes of osteoporosis by inhibiting MCP-1 secretion of BMSCs and the migration and apoptosis of T lymphocytes.
Animals ; Female ; Mice ; Apoptosis/genetics* ; Bone Marrow Cells/metabolism* ; Cell Differentiation ; Chemokine CCL2/metabolism* ; Mesenchymal Stem Cells/metabolism* ; MicroRNAs/metabolism* ; Osteogenesis ; Osteoporosis/genetics* ; T-Lymphocytes/metabolism*

Objective To investigate the effect of H₂O₂-induced oxidative stress on autophagy and apoptosis of human bone marrow mesenchymal stem cells (hBMSCs). Methods hBMSCs were isolated and cultured. The cells were divided into control group, 3-MA group, H₂O₂ group, H₂O₂ combined with 3-MA group. DCFH-DA staining was used to analyze the level of reactive oxygen species (ROS). hBMSCs were treated with 0, 50, 100, 200, 400 μmol/L H₂O₂, and then the cell viability was detected by CCK-8 assay. The level of autophagy was detected by monodansylcadaverine (MDC) staining and LysoTracker Red staining. The cell apoptosis was detected by flow cytometry. Western blotting was used to detect the expression of beclin 1, mTOR, phosphorylated mTOR (p-mTOR), cleaved caspase-3(c-caspase-3) and caspase-3 proteins. Results Compared with the control group and 3-MA group, ROS level and autophagosomes were increased and the proliferation and apoptosis were decreased in H₂O₂ group. The protein expression of beclin 1, mTOR, c-caspase-3 was up-regulated, while the p-mTOR was down-regulated. Compared with the 3-MA group, the H₂O₂ combined with 3-MA group also had an increased ROS level and autophagosomes, but not with significantly increased apoptosis rate; The protein expression of beclin 1, mTOR, c-caspase-3 was up-regulated, and the p-mTOR was down-regulated. Conclusion H₂O₂ can induce hMSCs to trigger oxidative stress response. It enhances the autophagy and inhibits the proliferation and apoptosis of hBMSCs.
Humans ; Beclin-1/metabolism* ; Caspase 3/metabolism* ; Reactive Oxygen Species/metabolism* ; Hydrogen Peroxide/pharmacology* ; Apoptosis ; TOR Serine-Threonine Kinases/metabolism* ; Oxidative Stress ; Autophagy ; Mesenchymal Stem Cells/metabolism* ; Cell Proliferation

OBJECTIVE: To investigate the expression of pyruvate kinase M2 (PKM2) in bone marrow mesenchymal stem cells (BMSCs) in myeloma bone disease (MBD) and its effect on osteogenic and adipogenic differentiation of BMSCs. METHODS: BMSCs were isolated from bone marrow of five patients with multiple myeloma (MM) (MM group) and five with iron deficiency anemia (control group) for culture and identification. The expression of PKM2 protein were compared between the two groups. The differences between osteogenic and adipogenic differentiation of BMSCs were assessed by using alkaline phosphatase (ALP) and oil red O staining, and detecting marker genes of osteogenesis and adipogenesis. The effect of MM cell line (RPMI-8226) and BMSCs co-culture on the expression of PKM2 was explored. Functional analysis was performed to investigate the correlations of PKM2 expression of MM-derived BMSCs with osteogenic and adipogenic differentiation by employing PKM2 activator and inhibitor. The role of orlistat was explored in regulating PKM2 expression, osteogenic and adipogenic differentiation of MM-derived BMSCs. RESULTS: Compared with control, MM-originated BMSCs possessed the ability of increased adipogenic and decreased osteogenic differentiation, and higher level of PKM2 protein. Co-culture of MM cells with BMSCs markedly up-regulated the expression of PKM2 of BMSCs. Up-regulation of PKM2 expression could promote adipogenic differentiation and inhibit osteogenic differentiation of MM-derived BMSCs, while down-regulation of PKM2 showed opposite effect. Orlistat significantly promoted osteogenic differentiation in MM-derived BMSCs via inhibiting the expression of PKM2. CONCLUSION The overexpression of PKM2 can induce the inhibition of osteogenic differentiation of BMSCs in MBD. Orlistat can promote the osteogenic differentiation of BMSCs via inhibiting the expression of PKM2, indicating a potential novel agent of anti-MBD therapy.
Humans ; Adipogenesis ; Bone Diseases/metabolism* ; Bone Marrow Cells ; Cell Differentiation ; Cells, Cultured ; Mesenchymal Stem Cells/physiology* ; Multiple Myeloma/metabolism* ; Orlistat/pharmacology* ; Osteogenesis/genetics*

OBJECTIVE: To explore the effect of hypoxia-supported umbilical cord mesenchymal stem cell (UC-MSC) on the expansion of cord blood mononuclear cell （MNC） in vitro. METHODS: The isolated cord blood mononuclear cells were inoculated on the preestablished umbilical cord mesenchymal stem cell layer and cultured under hypoxic conditions (3％ O₂) and the experimental groups were normoxia (MNCs were cultured under normoxic conditions), hypoxia (MNCs were cultured under hypoxic conditions), UC-MSC (MNCs were cultured with UC-MSC under normoxic conditions), and UC-MSC+hypoxia (MNCs were cultured with UC-MSC under hypoxic conditions). To further investigate the combinational effect of 3 factors of SCF+FL+TPO (SFT) on expansion of cord blood MNCs in vitro in hypoxia-supported UC-MSC culture system, the experiments were further divided into group A (MNCs were cultured with UC-MSC and SFT under normoxic conditions), group B (MNCs were cultured with UC-MSC under hypoxic conditions), group C (MNCs were cultured with UC-MSC and SFT under hypoxic conditions). The number of nucleated cells (TNC), CD34⁺ cell, CFU and CD34⁺CXCR4⁺, CD34⁺CD49d⁺, CD34⁺CD62L⁺ cells of each groups were detected at 0, 7, 10 and 14 days, respectively. RESULTS: Compared with group hypoxia and UC-MSC, group UC-MSC+hypoxia effectively promoted the expansion of TNC, CD34⁺ cell and CFU, and upregulated the expression level of adhesion molecule and CxCR4 of the cord blood CD34⁺ cell（P<0.05）. After culturing for 14 days, compared with group A and group B, group C effectively promoted the expansion of cord blood MNC at different time points（P<0.05）, and the effect of group A was better than that of group B at 7 and 10 days（P<0.05）. CONCLUSION Hypoxia-supported UC-MSC efficiently promoted the expansion and expression of adhesion molecule and CXCR4 of cord blood CD34⁺ cell, and the effect of expansion could be enhanced when SFT 3 factors were added.
Humans ; Cells, Cultured ; Fetal Blood ; Cell Proliferation ; Umbilical Cord/metabolism* ; Mesenchymal Stem Cells ; Antigens, CD34/metabolism* ; Hypoxia/metabolism*

Ex vivo culture-amplified mesenchymal stem cells (MSCs) have been studied because of their capacity for healing tissue injury. MSC transplantation is a valid approach for promoting the repair of damaged tissues and replacement of lost cells or to safeguard surviving cells, but currently the efficiency of MSC transplantation is constrained by the extensive loss of MSCs during the short post-transplantation period. Hence, strategies to increase the efficacy of MSC treatment are urgently needed. Iron overload, reactive oxygen species deposition, and decreased antioxidant capacity suppress the proliferation and regeneration of MSCs, thereby hastening cell death. Notably, oxidative stress (OS) and deficient antioxidant defense induced by iron overload can result in ferroptosis. Ferroptosis may inhibit cell survival after MSC transplantation, thereby reducing clinical efficacy. In this review, we explore the role of ferroptosis in MSC performance. Given that little research has focused on ferroptosis in transplanted MSCs, further study is urgently needed to enhance the in vivo implantation, function, and duration of MSCs.
Humans ; Antioxidants/metabolism* ; Ferroptosis ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stem Cells ; Iron Overload/metabolism*

The failure rate of dental implantation in patients with well-controlled type 2 diabetes mellitus (T2DM) is higher than that in non-diabetic patients. This due, in part, to the impaired function of bone marrow mesenchymal stem cells (BMSCs) from the jawbone marrow of T2DM patients (DM-BMSCs), limiting implant osseointegration. RNA N6-methyladenine (m6A) is important for BMSC function and diabetes regulation. However, it remains unclear how to best regulate m6A modifications in DM-BMSCs to enhance function. Based on the "m6A site methylation stoichiometry" of m6A single nucleotide arrays, we identified 834 differential m6A-methylated genes in DM-BMSCs compared with normal-BMSCs (N-BMSCs), including 43 and 790 m6A hypermethylated and hypomethylated genes, respectively, and 1 gene containing hyper- and hypomethylated m6A sites. Differential m6A hypermethylated sites were primarily distributed in the coding sequence, while hypomethylated sites were mainly in the 3'-untranslated region. The largest and smallest proportions of m6A-methylated genes were on chromosome 1 and 21, respectively. MazF-PCR and real-time RT-PCR results for the validation of erythrocyte membrane protein band 4.1 like 3, activity-dependent neuroprotector homeobox (ADNP), growth differentiation factor 11 (GDF11), and regulator of G protein signalling 2 agree with m6A single nucleotide array results; ADNP and GDF11 mRNA expression decreased in DM-BMSCs. Furthermore, gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses suggested that most of these genes were enriched in metabolic processes. This study reveals the differential m6A sites of DM-BMSCs compared with N-BMSCs and identifies candidate target genes to enhance BMSC function and improve implantation success in T2DM patients.
Humans ; Bone Marrow/metabolism* ; Bone Morphogenetic Proteins/metabolism* ; Dental Implants/adverse effects* ; Diabetes Mellitus, Type 2/metabolism* ; Growth Differentiation Factors/metabolism* ; Mesenchymal Stem Cells/metabolism* ; RNA/metabolism* ; RNA Processing, Post-Transcriptional