Atorvastatin ameliorates inflammatory hyperalgesia in rat model of monoarticular arthritis

Statins, the cholesterol lowering drugs, have been shown to exhibit anti-inflammatory properties. The aim of the present study was to evaluate the efficacy of atorvastatin in ameliorating joint dysfunction associated with arthritis. Monoarticular arthritis was induced by the intra-articular injection of FCA (0.1mL of 0.1%). The effect of atorvastatin (10 and 50mg/kg, A10 and A50) following oral administration was evaluated on joint inflammation, locomotor function and hyperalgesia daily for first 4 days and every 4th day till 28 days. The effect of atorvastatin was compared with that of diclofenac (5mg/kg, D5). Daily oral administration of atorvastatin produced a significant reduction in joint inflammation (21% in A10 and 33% in A50) and associated hyperalgesia. Atorvastatin also produced a marked improvement in the stair climbing ability and motility of the arthritic rats. The beneficial effect of atorvastatin was also evident from the histological analysis of joint carried out on day 28. Our results show that atorvastatin is more effective in decreasing the joint inflammation and hyperalgesia as compared to diclofenac while the efficacy of both the drugs in ameliorating functional disability was comparable.