Actein has a stimulatory effect on osteoblastic bone formation or has potential activity against osteoporosis, it also can prevent oxidative damage to osteoblasts in osteoporotic patients. Actein's ability to pathways involved in lipid disorders and carci

Actein, isolated from black cohosh, was subjected to in vitro experiments to investigate its functional bioactivities in osteoblastic MC3T3-E1 cells. METHODS AND RESULTS: Actein caused a significant elevation of alkaline phosphatase activity, collagen synthesis, osteocalcin production, mineralization, and glutathione content in the cells, suggesting that Actein has a stimulatory effect on osteoblastic bone formation or has potential activity against osteoporosis. We investigated the protective effects of Actein on mitochondrial electron transport inhibitor, antimycin A induced toxicity in osteoblastic MC3T3-E1 cells. Exposure of MC3T3-E1 cells to antimycin A caused significant decrease in cell viability and mineralization. However, pretreatment with Actein prior to antimycin A exposure significantly reduced antimycin A-induced cell damage by preventing mitochondrial membrane potential dissipation, complex IV inactivation, cardiolipin oxidation, ROS release, and nitrotyrosine increase, suggesting that Actein may be useful for protecting mitochondria against a burst of oxidative stress. In addition, Actein increased the phosphorylation of CREB (cAMP-response element-binding protein) inhibited by antimycin A and decreased the production of TNF-α induced by antimycin A. CONCLUSIONS:These findings suggest that Actein could prevent oxidative damage to osteoblasts in osteoporotic patients.