The Anti-oxidant Monoterpene p-Cymene Reduced the Occurrence of Colorectal Cancer in a Hyperlipidemia Rat Model by Reducing Oxidative Stress and Expression of Inflammatory Cytokines.

Abstract

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. 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. 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%). p-Cymene has clinical potential to reduce the incidence of CRC in hyperlipemia.