Anti-inflammatory effect of piperine in adjuvant-induced arthritic rats--a biochemical approach.

The present study was undertaken to investigate the anti-inflammatory effect of piperine against adjuvant-induced arthritis in rats, an experimental model for rheumatoid arthritis and compared it with that of the non-steroidal anti-inflammatory drug indomethacin. Administration of heat-killed Mycobacterium tuberculosis (0. 1 ml) intradermally into the right hind paw of rats resulted in increased paw volume, lysosomal enzymes, glycoproteins and tissue marker enzymes and decreased body weight. However, these changes were reverted to near normal levels upon piperine (30 mg/kg body weight, i.p.) treatment. Histopathological analysis of joints also revealed that synovial hyperplasia and mononuclear infiltration observed in arthritic rats were alleviated by piperine. Thus, the present study clearly indicated that piperine possesses promising anti-inflammatory effect against adjuvant-induced arthritis by suppressing inflammation and cartilage destruction.