Assessment of Antioxidant Effect of Beta-Glucan on the Whole Blood Oxidative DNA Damage with the Comet Assay in Colorectal Cancer

Objective: The present study aims to evaluate the antioxidant effect of beta-glucan on oxidative DNA damage by comet assay. Methods: A total of 19 adult females and males diagnosed with stage 3-4 colorectal cancer and a control group of 20 age-matched healthy subjects were enrolled in the study. Blood samples of the participants were analyzed using Comet Assay for the parameters of DNA damage. Results: Significantly increased DNA damage was observed in patients versus the control group as indicated by greater values of tail moment, tail percent DNA and tail length. Following incubation with β-glucan, a substantial reduction was found in the aforementioned parameters of DNA damage. Comet assay revealed significant levels of endogenous DNA damage in patients as shown by remarkable increases in the tail moment, the percentage of DNA in the tail and the tail length values, in comparison with the control group. Following treatment of fresh whole blood with β-glucan incubation, DNA damages were significantly reduced, but lower values were observed after β-glucan incubation in the patient group versus control group. Conclusion: β-Glucan was found to reduce DNA damage substantially in colorectal cancer patients and show antimutagenic effects. Our results suggested that dietary β-glucan intake might be important in the genesis of colorectal cancer tumors.