A high molecular weight protein extract of Mastobranchus indicus (Mi-64) having antiarthritic activity in experimental animals.

Mi-64, a high molecular weight protein (130 kDa), obtained from the tissue homogenate of marine polychaete (Mastobranchus indicus) collected from the Indian Sunderban has antiarthritic activity in experimental animals. The FCA-induced arthritis model was developed in Wistar albino rats to evaluate the antiarthritic effects of Mi-64. After FCA induction, the rats were treated with Mi-64 (0.25 and 0.5 mg kg(-1) body weight) for 10 days. We have determined the paw/ankle swellings, urinary hydroxyproline and glucosamine, serum acid and alkaline phosphatases to assess the antiarthritic activity. The levels of interleukin-1 beta (IL-1β), IL-6, cytokine-induced neutrophil chemoattractant-1 (CINC-1), tumor necrosis factor-alpha (TNF-α), and IL-10 were measured by ELISA. Results showed that Mi-64 significantly reduced paw/ankle swellings and restored the urinary hydroxyproline/glucosamine and serum phosphatases. Mi-64 significantly inhibited the overproduction of IL-1β, IL-6, CINC-1, and TNF-α and augmented IL-10 production. The data suggest that Mi-64 produced significant antiarthritic effects that may be mediated by balancing the pro- and anti-inflammatory cytokines.