Cangxitongbi capsules protect the articular cartilage in the rat knee through the long non-coding RNA HOTAIR/p38MAPK pathway

Background: Knee osteoarthritis (KOA) is a leading cause of chronic pain and disability, and as such, it poses a significant economic burden. Traditional Chinese medicine (TCM), as well as complementary and alternative medicine, can offer safe and effective treatments for KOA. Cangxitongbi (CXTB) capsule is a Chinese patented medicine for KOA treatment and has a remarkable curative effect. This article evaluated the effects and mechanisms of CXTB in protecting joint cartilage in vivo. Methods: The KOA model was constructed in rats using the modified Hulth method. CXTB (35 mg/kg) was administered intragastrically for 4 weeks. Hematoxylin and eosin (HE) staining of the knee articular were performed to evaluate the efficiency of CXTB. Western blot analysis, quantitative polymerase chain reaction (qPCR), and enzyme-linked immunosorbent assay (ELISA) were used to investigate the protective mechanisms of CXTB in joint cartilage. Results: CXTB effectively improved the morphological structure of the cartilage and bone in the knee joint by enhancing autophagy and regulating the expression of related protease and inflammatory factors. Furthermore, CXTB downregulated the expression of the long non-coding RNA (lncRNA) Hox transcript antisense intergenic RNA (HOTAIR) and inhibited the activation of the p38MAPK pathway. Conversely, overexpression of lncRNA HOTAIR suppressed the protective effects of CXTB on the knee joint. Conclusions: CXTB capsules can protect the knee articular cartilage in rats through the lncRNA HOTAIR/p38MAPK pathway.