Schisandrin B alleviates osteoporosis by restoring intestinal microbiota homeostasis

Osteoporosis is a metabolic bone disease characterized by reduced bone mass and destruction of bone microstructure, which is highly prevalent in middle-aged and elderly populations and postmenopausal women. Patients are extremely prone to fractures, and current clinical treatment options have limited efficacy. Schisandrin B, a lignan active component extracted from the traditional Chinese herb Schisandra chinensis, not only exhibits multiple biological activities such as anti-oxidation, anti-inflammation, and liver protection but also effectively improves osteoporotic symptoms by regulating bone metabolism. Intestinal microbial homeostasis refers to the dynamic balance of the types, quantities, and functions of intestinal flora, which plays a crucial role in the host's metabolism, immune function, and skeletal health. In this study, the effects of Schisandrin B on bone metabolism in osteoporosis were systematically investigated through in vitro culture of MC3T3-E1 cells and in vivo construction of ovariectomized mouse models with Schisandrin B intervention. Meanwhile, advanced experimental techniques such as 16S rRNA gene sequencing and liquid chromatography-mass spectrometry were used to deeply analyze the regulatory mechanism of Schisandrin B on intestinal microbial flora. The results showed that Schisandrin B significantly improved osteoporotic symptoms by regulating intestinal microbial homeostasis, which was further confirmed by validation experiments using antibiotic mixtures to deplete intestinal microbiota. This study provides new research ideas and directions for the treatment of osteoporosis.