Mangiferin Inhibits Inflammation and Cell Proliferation, and Activates Proapoptotic Events via NF-κB Inhibition in DMBA-Induced Mammary Carcinogenesis in Rats

The purpose of this study was to investigate the anti-inflammatory, antiproliferatiive, and proapoptotic molecular mechanisms of mangiferin (MGN) against mammary carcinogenesis induced by 7,12-dimethylbenz(a)anthracene (DMBA). Mammary cancer in rats was induced by single-dose subcutaneous injection of 0.5 ml DMBA (80 mg/kg in sesame oil) in the mammary gland. Increased tumor incidence and volume and other tumorigenic properties were observed. Further, we observed in these rats reduced antioxidant enzyme activity and elevated thiobarbituric acid reactive substance (TBARS) levels in plasma and tissues. DMBA-induced rats shows enhanced expression of the inflammatory markers NF-κBp65, COX-2, and iNOS and proliferation of PCNA and Cyclin D1, and overexpression of the antiapoptotic marker Bcl-2. Mangiferin (100 mg/kg body weight), administered orally once per day, significantly enhanced (p < 0.05) antioxidant levels and reduced TBARS levels. Moreover, MGN inhibited NF-κBp65 nucleus transcriptional activation, thereby suppressing inflammation and cell proliferation, and it increased proapoptotic proteins. Apoptosis was confirmed by TUNEL assay. In summary, MGN suppressed DMBA-induced mammary carcinogenesis through enhanced antioxidant levels, NF-κB inhibition, and positive regulation of apoptotic signals.