2022, Vol. 26 ›› Issue (24): 3846-3851

Osteogenic differentiation of bone marrow mesenchymal stem cells in obese mice

Chen Chichi1, 2, Zhang Yu1, 2, He Jiachen1, 2, Shi Qin1, 2   

Abstract: BACKGROUND: The differentiation of bone marrow mesenchymal stem cells is affected by many factors. The bone marrow mesenchymal stem cells of obese mice have better osteogenic differentiation ability.   
OBJECTIVE: To explore the difference of osteogenic differentiation of bone marrow mesenchymal stem cells from obese mice induced by high fat diet and normal diet mice.
METHODS:   Balb/c mice aged 4-6-weeks were randomly divided into normal diet group and high-fat diet group for 20 weeks. Bone marrow mesenchymal stem cells were isolated by whole bone marrow culture. After 7 days of osteogenic induction, alkaline phosphatase staining and qRT-PCR were performed to detect the expression of osteogenic related genes. At 14 days after osteogenic induction, alizarin red staining was performed. After 20 weeks of high-fat feeding, changes of bone mass of femur were analyzed by Micro-CT. The decalcified sections of the mouse femur were stained with hematoxylin and eosin.   
RESULTS AND CONCLUSION: (1) Compared with the mice in the normal diet group, after 20 weeks of high-fat feeding, the weight of the mice increased significantly. (2) Compared with the bone marrow mesenchymal stem cells of mice in the normal diet group, the expression of alkaline phosphatase and the number of calcium nodules in the bone marrow mesenchymal stem cells of mice in the high-fat diet group increased significantly, and the expression levels of osteogenic related genes alkaline phosphatase, osteopontin and RUNT-related transcription factor 2 elevated. (3) The results of Micro-CT reconstruction and bone morphological parameter quantification showed that compared with the normal diet group, the high-fat diet group had a significant increase in bone mass, including bone mineral density, bone volume fraction, bone area to bone volume ratio, bone trabecular thickness, and bone trabecular number increased significantly, while the trabecular separation significantly reduced. Hematoxylin-eosin staining showed that there were more trabecular bones in the femur of the high-fat diet group. (4) It is concluded that osteogenic differentiation ability of bone marrow mesenchymal stem cells in obese mice is enhanced, which further leads to a significant increase in bone mineral density, bone trabecular thickness, and bone trabecular number, and also in the bone mass in mice.
Key words: stem cells, bone marrow mesenchymal stem cells, normal diet, high-fat diet, obesity, osteogenesis induction, osteogenic differentiation, mice