Curcumin has a wide spectrum of biological, pharmaceutical, and antioxidant effects in cancer experimental models. Nitrosamine is commonly used as an experimental oxidizing agent which induces gastric oxidative stress and gastric carcinogenesis in rats. We examined the antioxidant potential effect of curcumin against nitrosamine-induced gastric oxidative stress in rats. Forty Sprague-Dawley rats were randomly divided into 4 groups (10 rats/group). The control group was fed a standard diet and received a single dose of normal saline, the nitrosamine-treated group was fed a standard diet and received an intraperitoneal injection of nitrosamine at a single dose of 100 mg/kg body weight (b.w.). The other two groups received a daily dose of curcumin (200 mg/kg b.w.) via intra-gastric intubation in the presence or absence of nitrosamine injection. After 16 weeks, all rats were sacrificed, and the gastric tissues were dissected for histopathological examination and for biochemical measurements of oxidative stress indices. Our results showed that nitrosamine causes oxidative stress in gastric tissues as evidenced by glutathione depletion, increased level of lipid peroxides, nitric oxide release, impairment of total antioxidant capacity, DNA oxidative damage, and inhibition of antioxidant enzymes (catalase, glutathione peroxidase, glutathione reductase, and superoxide dismutase). Histopathological findings revealed abnormal gastric architecture in association with nitrosamine injection compared to the non-treated control group. Curcumin significantly suppressed the gastric oxidative damage associated with nitrosamine treatment and mitigated its histopathological effect. These results suggest that curcumin, as an antioxidant, has a therapeutic effect against oxidative stress-mediated gastric diseases.

BackgroundNitrosamine acts as a carcinogenic agent and induces gastric cancer in rats. The mechanisms underlies nitrosamine‐mediated gastric cancer pathogenesis need to be investigated. Experimental studies continue to support the notion that curcumin combat cancer by acting as a dietary antioxidant.ObjectiveOur study model was undertaken to investigate the preventive effect of curcumin supplementation against nitrosamine‐induced oxidative stress and carcinogenesis in rat stomach.MethodsForty Sprague‐Dawley rats (8 weeks old) were randomly divided into 4 groups (10 rats/group). Control group was fed a standard rat chow diet; nitrosamine‐treated group was fed a standard rat chow diet and also received intraperitonial injections of nitrosamine. The other two groups received oral supplementations of curcumin in the presence or absence of nitrosamine injection. All animals were fed ad‐libitum for 16 weeks. At the end of the experiment all rats were sacrificed and the gastric tissues were examined microscopically for gastric cancer lesions development, and for biochemical measurements of oxidative stress indices.ResultsOur results showed that nitrosamine causes gastric cancer development, as well as inducing oxidative stress in gastric tissue as evidenced by glutathione depletion and inhibition of antioxidant enzymes. The concomitant treatment of nitrosamine with curcumin significantly ameliorated the cytotoxic effects of nitrosamine.ConclusionThe results of this study provide in vivo evidence that curcumin supplementation protects against nitrosamine‐induced gastric cancer in the used animal model.Support or Funding InformationThis research was supported by Strategic Grant Funding (CL/SQU‐UAEU/15/03) and Internal Grant Funding (IG/AGR/FOOD/17/1), College of Agricultural and Marine Sciences, Sultan Qaboos UniversityThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.