Endocrine Abstracts

JOINT3771

Introduction: Osteoporosis is a systemic bone metabolic disorder caused by reduced bone formation and increased bone resorption. Currently, there are several anti-resorption drugs and osteosynthesis drugs that are effective in the treatment of osteoporosis, but their use is limited due to contraindications and side effects. In regenerative medicine, the unique repair ability of mesenchymal stem cells (MSCs) has gained significant attention from researchers. The exosomes secreted by MSCs possess signal transduction and molecular delivery mechanisms, which may have therapeutic effects.

Methods: MSCs were initially isolated from human bone marrow. After the surface antigen of MSCs was identified using flow cytometry, MSC-derived exosomes (MSC-Exo) were extracted. The osteogenic and adipogenic differentiation abilities of BMSCs were assessed using alizarin red staining and oil red O staining, respectively. Quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was employed to analyze the mRNA expression of various genes. The cell viability of osteoblasts was determined using the Cell Counting Kit-8 (CCK-8) assay. Western blotting was used to measure the expression of specific surface markers in exosomes and the MAPK pathway-related proteins in osteoblast cells. Additionally, the cell cycle of osteoblasts was analyzed by flow cytometry.

Results: We found that surface antigens were positively expressed in MSCs, indicating a strong multipotent differentiation ability. The isolated MSC-Exo exhibited typical exosome morphology and particle size, with the detection of specific surface-labeled proteins being positive under electron microscopy. After co-culturing MSC-Exo with the osteoblast cell line, we observed that MSC-Exo could promote the proliferation of osteoblast cells. Additionally, mRNA and protein expression levels in the cells were increased, and the cell cycle was also enhanced.

Conclusion: MSCs-derived exosomes have the potential to promote osteoblast proliferation by inhibiting cell apoptosis, ultimately improving osteoporosis. We suggest that MSCs-derived exosomes could be a promising therapeutic approach for osteoporosis in the future.