Protective effects of trans-caryophyllene on maintaining osteoblast function

Age-related osteoblast dysfunction is the main cause of age-related bone loss. Trans-caryophyllene (TC) is an important constituent of the essential oils derived from several species of medicinal plants. In this study, we investigated the effects of TC on osteoblast function in osteoblastic MC3T3-E1 cells. The results indicate that TC caused a significant elevation in collagen content, alkaline phosphatase activity, osteocalcin production, and mineralization, which are the four markers that account for the various stages of osteoblastic differentiation. In addition, pretreatment with TC prior to antimycin A exposure significantly reduced antimycin A-induced cell damage by attenuating cell death, preventing the release of reactive oxygen species and impeding osteoblast dysfunction. TC has been shown to be an agonist of the cannabinoid type 2 receptor (CB2R), and the effects of TC on osteocalcin secretion and matrix mineralization were abolished in MC3T3E1 cells transfected with CB2R siRNA. Our findings that TC promotes the formation of a mineralized extracellular matrix help to elucidate the role of CB2 signaling in the formation of bone and the maintenance of normal bone mass. © 2016 IUBMB Life, 69(1):22-29, 2017.