Abstract
Korean Red Ginseng (KRG) exerts chemopreventive effects on experimentally induced carcinogenesis through multiple mechanisms. In this study, we investigated effects of KRG on dextran sulfate sodium (DSS)-induced colitis and azoxymethane (AOM) plus DSS-induced colon carcinogenesis in mice. Male C57BL/6J mice were fed diet containing 1% KRG or a standard diet throughout the experiment. The mouse colitis was induced by administration of 3% DSS in drinking water for 1 week. DSS caused body weight loss, diarrhea, rectal bleeding and colon length shortening, and all these symptoms were ameliorated by KRG treatment. KRG inhibited DSS-induced expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) by suppressing activation of nuclear factor-kappa B (NF-κB) and signal transducer and activation of transcription 3 (STAT3). In another experiment, colon carcinogenesis was initiated by single intraperitoneal injection of AOM (10 mg/kg) and promoted by 2% DSS in drinking water. KRG administration relieved the symptoms of colitis and reduced the incidence, the multiplicity and the size of colon tumor. The up-regulation of COX-2, iNOS, c-Myc and Cyclin D1 by AOM plus DSS was attenuated in KRG fed mice which was associated with suppression of NF-κB and STAT3 activation. These results suggest that KRG is a potential candidate for chemoprevention of inflammation-associated cancer in the colon.