Antioxidant, genoprotective and immunomodulatory potential of Vitex negundo leaves in experimental arthritis

Abstract

Vitex negundo is a medicinal plant used in Indian and folklore medicines to cure various ailments including arthritis. In the present study, the hydroethanolic extract of V. negundo leaves (VNE) were evaluated for antioxidant, genoprotective and immunomodulatory activity in Freund’s complete adjuvant (FCA) induced arthritis. VNE was evaluated for in vitro antioxidant activity using various parameters including plasmid nicking assay. VNE (200 mg/kg body weight) was orally administered to FCA induced arthritic rats to evaluate its genoprotective effects on peripheral blood leukocytes using the alkaline comet assay. Furthermore, the effects of VNE treatment on serum proinflammatory mediators such as tumor necrosis factor-α (TNF-α) and interleukin -1α (IL-1α) and the hematological parameters such as total RBC count, hematocrit and hemoglobin were measured in arthritic rats. The results showed that VNE exhibited potential in vitro antioxidant and DNA protecting activities in a concentration dependent manner. The phytoconstituents of VNE showed a strong and positive correlation with the antioxidant properties. DNA damage in the peripheral blood leukocytes of arthritic animals was significantly decreased after VNE treatment. VNE showed inhibition of serum proinflammatory cytokines (TNF-α and IL-1α) however, the inhibition was statistically not-significant. The arthritic animals showed significant increase in hemolysis, which was restored by VNE treatment. The results of the present study indicate that VNE may be a source of antioxidant, genoprotective with immunomodulatory activity, which may be attributed to its antioxidant phytoconstituents.