Chemopreventive effect of carvacrol on 1,2-dimethylhydrazine induced experimental colon carcinogenesis

Colorectal cancer (CRC) is a leading cause for cancer-related death and its prevention is of great importance throughout the world. Chemoprevention offers a novel approach to control the incidence of colon cancer. The present study was performed to evaluate the efficacy of carvacrol supplementation on colonic aberrant crypt foci (ACF), lipid peroxidation, and antioxidant defense system in 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis in male Wistar rats.

The rats were randomly divided into six groups. Group 1, control rats received modified pellet diet; Group 2 rats received modified pellet diet along with carvacrol (80 mg/kg b.wt/day); Groups 3-6 received subcutaneous injection of DMH (20 mg/kg b.wt), once a week for the first 4 weeks; in addition Groups 4-6 received carvacrol at three different doses of 20, 40, and 80 mg/kg b.wt/day for 16 weeks.

Our result suggest that increased tumor incidence and increased number of ACF, increased bacterial enzymes accompanied by a decrease in the colonic lipid peroxidation, glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) activities were observed in DMH-treated rats. Administration of carvacrol to DMH-treated rats significantly decreased the tumor incidence and the number of ACF and bacterial enzymes with enhancement of colonic lipid peroxidation, GPx, SOD, and CAT activities.

The results of this study suggest that carvacrol at a dose of 40 mg/kg b.wt showed a significant beneficial effect against chemically-induced colon carcinogenesis in rats.