Salvianolic acid B alleviate the osteoblast activity decreasing under simulated microgravity by Keap1/Nrf2/ARE signaling pathway

Abstract

Astronauts suffer bone loss during long-term space flight, and the bone loss is hard to recover after returning to the ground. Salvianolic acid B (Sal B) is proved to have stimulation effect on osteoblasts. In order to study the mechanisms on the protect effect of Sal B on simulated microgravity (SMG)-induced osteoblast proliferation inhibition, cell proliferation, cell apoptosis, antioxidant activity and related osteogenic gene expression of osteoblasts were studied. Results show that osteoblasts proliferation was increased by Sal B. And it can also reduce apoptosis under SMG. In case of anti-oxidation, Sal B decreases the whole content of MDA, stimulates the activity of SOD, CAT and LDH. Meanwhile, the expression of Nrf2, HO-I, Runx2, Osx, OPN, ALP and Col-I was up-regulated by Sal B. In conclusion, by stimulating the osteoblasts’s activity and the capacity of anti-oxidation, salvianolic acid B has a protection effect on osteoblasts under SMG.

Keywords

• Salvianolic acid B
• Osteoblast
• Simulated microgravity
• Antioxidant