The Anti-oxidant Monoterpene<i>p</i>-Cymene Reduced the Occurrence of Colorectal Cancer in a Hyperlipidemia Rat Model by Reducing Oxidative Stress and Expression of Inflammatory Cytokines
Shuiming Wang, Xiaofeng Wang, Y U Wang, Qiang Leng, Yu Sun, Robert M. Hoffman, Heiying Jin
Abstract
BACKGROUND/AIM: Overexpression of inflammatory cytokines and oxidative stress increase the risk of colorectal cancer (CRC) in obesity and hyperlipidemia. The aim of this study was to investigate whether the monoterpene antioxidant p-cymene would reduce the incidence of CRC in a rat model of hyperlipidemia. MATERIALS AND METHODS: The hyperlipidemic CRC rat model was established by a high-fat diet and dimethyl hydrazine (DMH) induction. All rats received 30 mg/kg DMH to induce CRC, and were then assigned to groups with a normal diet or high-fat diet with/without 30 mg/kg/day p-cymene orally during the entire experimental period. Tumor incidence in each group, and the level of serum inflammatory cytokines and oxidative stress-related markers in intestinal tissues were measured. RESULTS: p-Cymene significantly inhibited CRC occurrence in hyperlipemic rats (p=0.024) by reducing the expression of serum inflammatory cytokines (interleukin-1 by 54.5%; interleukin-6 by 28.3%; adiponectin by 26.3%; cyclo-oxygenase-2 by 48.4%) and intestinal oxidative-stress cytokines (total antioxidant capacity by 30.4%; superoxide dismutase by 30.3%; malondialdehyde by 47.1%). CONCLUSION: p-Cymene has clinical potential to reduce the incidence of CRC in hyperlipemia.