Panax quinquefolium saponin inhibits endoplasmic reticulum stress-induced apoptosis and the associated inflammatory response in chondrocytes and attenuates the progression of osteoarthritis in rat

Treatments for osteoarthritis (OA) seek to restore chondrocyte function and inhibit cell apoptosis. Panax quinquefolium saponin (PQS) is the major active ingredient of Radix panacis quinquefolii (American ginseng), and has been demonstrated to exert anti-inflammatory and anti-apoptotic effects in various diseases. However, any potential effect of PQS on the pathological process of OA remains unclear. This work aimed to explore the role of PQS in chondrocytes and to clarify its potential mechanisms. We showed that PQS treatment could protect chondrocytes against endoplasmic reticulum (ER) stress and associated apoptosis induced by interleukin (IL)-1 beta. Also, PQS further attenuated triglyceride (TG)-induced ER stress and associated apoptosis. Moreover, PQS may inhibit the ER stress-activated NF-kappa B pathway and associated inflammatory response in chondrocytes. Finally, PQS abolished rat cartilage degeneration in an in-vivo OA model of the knee joint. Our results indicate that PQS may be a potential novel treatment for OA.