Abstract: This study aimed to explore the effect of Astragalus membranaceus on the cell activity of osteogenic differentiation of BMSCs in hypoxic environments based on the PI3K/AKT signaling pathway. BMSCs cultured in osteogenic differentiation at low oxygen concentration (10%) were intervened with astragalus lyophilized powder solution at low, medium and high doses (100, 200 and 300 μg·mL^-1), respectively, and the dynamic proliferation and differentiation generations of BMSCs were observed by high-intrinsic real-time imaging system; label-free tracing was performed to simulate cell movement trajectories and analyze the cell movement speed, displacement and movement distance of each group. The cellular mitochondrial membrane potential was observed by laser confocal microscopy, and the changes of PI3K/AKT signaling pathway-related proteins and gene expression levels were detected by immunofluorescence and RT-PCR. Results were as follows: Compared with the control group, 10% hypoxia concentration inhibited the proliferation of BMSCs, reduced their differentiation generations, slowed down the motility, displacement and movement distance of BMSCs; at the same time, the mitochondrial membrane potential activity decreased, p-PI3K and p-AKT protein expression decreased, PI3K and AKT gene expression level decreased, the difference was statistically significant (P<0.01). Compared with the hypoxia group, astragalus lyophilized powder solution intervention significantly maintained the proliferation and differentiation activity of BMSCs in hypoxic environment, increased motor viability, increased mitochondrial membrane potential activity, and increased expression of p-JAK2, p-STAT3 proteins and PI3K and AKT genes, with statistically significant differences (P<0.05 or 0.01). Astragalus maybe maintain the proliferative activity of BMSCs under hypoxic conditions by activating PI3K/AKT signaling pathway.

Key words: hypoxia, bone marrow mesenchymal stem cells, astragalus, proliferative activity, PI3K/AKT signaling pathway