Osteogenic and adipogenic differentiation of bone marrow mesenchymal stem cells under directional induction / 中国组织工程研究

ABSTRACT

BACKGROUND:Bone marrow mesenchymal stem cels are non-hematopoietic stem cels from the bone marrow and can differentiate into chondrocytes, osteocytes and adipocytes under different induction conditions, which are the most promising seed cels for tissue engineering. OBJECTIVE:To evaluate the osteogenic and adipogenic differentiation of bone marrow mesenchymal stem cels under directional induction. METHODS:Bone marrow samples from Japanese rabbits were extracted asepticaly to isolate and purify bone marrow mesenchymal stem cels using density gradient centrifugation and cel adherent method. Then, the cels were cultured in osteogenic and adipogenic induction media as experimental group. Another cels cultured in DMEM medium acted as control group. Sudan IV staining, Von Kossa staining and alkaline phosphatase activity detection were performed at different time after culture to compare the osteogenic and adipogenic rates. RESULTS AND CONCLUSION:After 7 days of adipogenic induction, smal lipid droplets were visible and the cels arranged disorderly; at 21 days of induction, see lipid droplets with high refractivity were seen in the cytoplasm. Sudan IV staining showed that there were a large amount of red lipid droplets in the cloning center of bone marrow mesenchymal stem cels, but only 5% bone marrow mesenchymal stem cels differentiated into adipocytes in the control group. At 7 days of osteogenic induction, induced cels were confluent in a flagstone shape, and there were many nodules; at 14 days of culture, the center of brown mineralized nodules were visible; at 21 days of culture, smal pieces of mineralized nodules formed. The osteogenic and adipogenic rates were 40% and 20% in the experimental group, respectively, which were higher than those in the control group (5%, 5%). These findings indicate that under certain conditions, bone marrow mesenchymal stem cels can partialy differentiate into fat cels part, and another part differentiate into osteocytes, suggesting there is a certain link between them, that is, more adipocytes and fewer osteoblasts, or vice versa.