Ginsenoside‑Rg5 treatment inhibits apoptosis of chondrocytes and degradation of cartilage matrix in a rat model of osteoarthritis.

This study investigated the effect of ginsenoside‑Rg5 on the degradation of articular cartilage in osteoarthritis rat model and on induction of chondrocyte apoptosis. Osteoarthritis rat model was prepared by ligament transection and medial meniscus resection. The rats were then treated with different doses (1, 2, 5, 10 and 15 µM) of ginsenoside‑Rg5 for 48 h. The results from histopathological analysis revealed a significant (P=0.005) prevention of cartilage degradation in OA rat model by ginsenoside‑Rg5 treatment at 15 µM. Ginsenoside‑Rg5 treatment prevented the disintegration of synovial membrane to a significant (P=0.005) extent. The proportion of apoptotic cells in the knee joints was reduced to 7% by ginsenoside‑Rg5 treatment after one month compared to the control. Treatment of the rats with ginsenoside‑Rg5 caused increase in the levels of proteoglycan, collagen and type II collagen by 5-, 3- and 4-fold compared to the control group. Immunohistochemistry revealed that the level of MMP-13 was reduced to 45% and that of TIMP‑1 was increased by 67% on treatment with ginsenoside‑Rg5. The levels of interleukin-1β, tumor necrosis factor-α, nitric oxide and inducible nitric oxide synthetase were reduced by 67, 54, 32 ad 49%, respectively after one month of treatment with 15 mg/kg dose of ginsenoside‑Rg5. The expression was increased to 67 and 52% for BMP-2 and TGF-β1, respectively on treatment with ginsenoside‑Rg5. Thus ginsenoside‑Rg5 prevents cartilage degradation in the OA rats and inhibits cartilage apoptosis, therefore it can be used for osteoarthritis treatment.