Effects of karanjin on dimethylhydrazine induced colon carcinoma and aberrant crypt foci are facilitated by alteration of the p53/Bcl2/BAX pathway for apoptosis

We investigated the effects of karanjin on dimethylhydrazine (DMH) induced colon cancer in rats. Male Wistar rats were injected with DMH followed by dextran sodium sulfate in drinking water for 7 days. Karanjin at doses of 50,100 and 200 mg/kg was administered orally for 18 weeks. Colon tissues were investigated using TUNEL analysis of apoptosis; histopathological assessment including number of aberrant crypt foci (ACF); immunohistochemical staining for Bcl-2-associated X protein (BAX), B-cell lymphoma 2 (Bcl2), p53 and proliferating cell nuclear antigen (PCNA); and antioxidant assay in vivo. We found that treatment with karanjin inhibited formation of ACF in the colon mucosa and reduced colon lesions. Karanjin treatment also increased the antioxidants, catalase, glutathione and superoxide dismutase. Immunostaining showed that karanjin treatment reduced BAX, p53 and PCNA levels and increased Bcl2 expression. The TUNEL assay revealed that karanjin induced apoptosis in the colon mucosa. Our findings suggest that karanjin can ameliorate colon carcinogenesis in rats by regulating BAX, Bcl2 and p53 pathways.