Piperine ameliorates oxidative stress, inflammation and histological outcome in collagen induced arthritis

Objectives: Piperine, a main component of Piper species, is a plant alkaloid with a long history of medical use in a variety of inflammatory disorders like rheumatoid arthritis. Due to side effects in current treatment modalities of rheumatoid arthritis, the interest in alternative, well tolerated anti-inflammatory remedies has re-emerged. The aim of this work was to evaluate the anti-inflammatory and antiarthritic effects of piperine. Methods: Arthritis was induced in male Wistar rats by collagen induced arthritis (CIA) method. Piperine was administered at a dose of 100mgkg^-1 and indomethacin at 1mgkg^-1 body weight once daily for 21days. The effects of treatment in the rats were assessed by biochemical (articular elastase, MPO, LPO, GSH, Catalase, SOD and NO), inflammatory mediators (IL-1β, TNF-α, IL-10 and PGE₂) and histological studies in joints. Results: Piperine was effective in bringing significant changes on all the parameters (articular elastase, MPO, LPO, GSH, Catalase, SOD and NO) studied. Oral administration of piperine resulted in significantly reduced the levels of pro-inflammatory mediators (IL-1β, TNF-α and PGE₂) and increased level of IL-10. The protective effects of piperine against RA were also evident from the decrease in arthritis scoring and bone histology. Conclusions: In conclusion, the fact that piperine alter a number of factors known to be involved in RA pathogenesis indicates that piperine can be used similar to indomethacin as a safe and effective therapy for CIA and may be useful in the treatment of rheumatoid arthritis.