Curcumin Pretreatment Evokes Lympho Proliferative Responses and Macrophage Activation to Negate Chromate-Induced Immuno Suppression in Vitro

Sreepriya. M

The effects of curcumin pretreatment to negate chromate (VI)-induced cytotoxicity and oxidative stress was evaluated in vitro on human peripheral blood lymphocytes and murine macrophages RAW 264.7. Chromate treatment at a dosage of 10µg/ml resulted in significant immunosuppression evident from the severe growth inhibition and cytotoxicity in both lymphocytes as well as macrophages which is revealed by MTT assay and LDH leakage. A decrease in the percentage phagocytosis, phagocytic index and depleted glutathione status was also observed in the macrophages subjected to chromate treatment. In addition to this, chromate treatment resulted in an increase in fragmented DNA (quantified by colorimetry) in the lymphocytes suggestive of severe cellular stress and apoptotic cell death. Curcumin pretreatment at a dose of 20µg/ml was able to protect both lymphocytes and macrophages against chromate induced toxic effects as evidenced by the increase in percentage survival and cell viability, increased percentage phagocytosis, phagocytic index and improved thiol status in the macrophages concomitant with a decrease in fragmented DNA in lymphocytes. This shows the influence of curcumin to ameliorate the altered immune responses and adverse changes induced by treatment with hexavalent chromium. The results of the study reveal the beneficial effects of curcumin supplementation to negate the toxic changes induced by chromate (VI).