Naringenin reduces tumor size and weight lost in N-methyl-N'-nitro-N-nitrosoguanidine-induced gastric carcinogenesis in rats.

Carcinoma of the stomach is reportedly the second most common cancerous condition affecting the general population. Administration of antioxidants is reported to effectively alleviate the risk of gastric carcinoma. Therefore, we assessed the protective role of naringenin, an antioxidant and naturally occurring citrus flavanone, on gastric carcinogenesis induced by MNNG (200 mg/kg body weight) and S-NaCl (1 mL per rat) in Wistar rats (obtained from the Central Animal House Facility, University of Madras, Taramani Campus, Chennai, India). The animals were divided into 5 groups, and the effects of naringenin on simultaneous and posttreated stages of MNNG were tested. Cancer risk was analyzed along with their antioxidant status. The LPO levels in the experimental groups were assessed as an index of oxidative milieu. Altered redox status was subsequently investigated by assaying the superoxide and hydroxyl radicals, the enzymatic antioxidants (SOD, CAT, GPx), and the nonenzymatic antioxidants viz reduced GSH, vitamin C, and vitamin E. In the presence of MNNG, cancer incidence and LPO levels were significantly increased, whereas enzymatic (SOD, CAT, and GPx) and nonenzymatic antioxidant activities (GSH, Vitamins C, and E) were decreased in the treated rats compared with control rats. Administration of naringenin to gastric carcinoma-induced rats largely up-regulated the redox status to decrease the risk of cancer. We conclude that up-regulation of antioxidants by naringenin treatment might be responsible for the anticancer effect in gastric carcinoma.