Protective effect of ShaoYao decoction on colitis-associated colorectal cancer by inducing Nrf2 signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Ulcerative colitis were prone to develop into ulcerrelated colorectal cancer with high risk of mortality. Shaoyao Decoction (SYD), a compound prescription of Chinese traditional medicine, was reported to have anti-colorectal cancer effect. Thus this study mainly investigated the protective and preventive effect of SYD against oxidative damages and inflamatory response through in vivo and in vitro experiments.

AIM OF THE STUDY: Shaoyao decoction (SYD), a compound prescription of traditional Chinese medicine, is effective in treating ulcerative colitis. The increased levels of reactive oxygen species (ROS) in inflammatory cells potentially drive the development of carcinomas. Nuclear factor-erythroid 2-related factor 2 (Nrf2) has became a novel target for the prevention of colorectal cancer (CRC). In this study, we assessed the antioxidation effect of SYD against colitis associated colorectal cancer through in vivo and in vitro experiments.

MATERIALS AND METHODS: In vivo AOM/DSS-induced murine model of colon cancer and in vitro H2 O2 -induced oxidative stress in HT-29 cells model were conducted. To determine the antioxidant activity of SYD, protein expression of Nrf2 and its downstream genes were detected by western blot, RT-PCR and Enzyme-linked immunosorbent assay.

RESULTS: Both in vivo and in vitro experiments demonstrated that SYD exerts antioxidant effect through activation of Nrf2 pathway and upregulation expression of Nrf2 downstream genes. SYD is shown to have preventive effect against colitis-associated colorectal cancer.

CONCLUSIONS: These observations suggest that SYD is effective in the enhancement of antioxidant ability via activation of Nrf2 pathway and the up-regulation of Nrf2-downstream phase II enzymes expression. The anti-inflammation and antioxidant action of SYD together contributes to the prevention and treatment of ulcerrelated colorectal cancer.