Antioxidant Status, Lipid Peroxidation and Protein Oxidation in Type 2 Diabetic Patients Beneficial Effects of Supplementation with Carnosine: A Randomized, Double-Blind, Placebo-Controlled Trial

Background: Oxidative stress in the pathogenesis of diabetes is of great prominence and that Carnosine is a natural antioxidant. Objectives: This study was aimed to investigate the effect of Carnosine supplementation on different oxidative stress biomarkers in patients with type 2 diabetes mellitus (T2DM). Methods: In this randomized, double-blind placebo-controlled trial, 54 patients with T2DM were employed from Tabriz Sheikhor-races polyclinic and Tabriz Imam Reza Hospital, endocrine center, and assigned into either the intervention group (n =27) to receive two capsules of Carnosine 500 mg each or the control group (n = 27) to take two capsules of crystalline microcellulose for 12 weeks. Serum levels of fasting blood sugar (FBS), malondialdehyde (MDA), protein carbonyl (PC) and erythrocytes content of catalase (CAT), and superoxide dismutase (SOD) were assessed before and after the supplementation. Results: A total of 44 patients completed the study. Anthropometric indices and energy intake didn't show a significant change in both studied groups. Improved catalase level and decreased serum levels of fasting blood sugar, malondialdehyde and protein carbonyl occurred in the carnosine group compared to the placebo group after adjusting for baseline values and confounders (P < 0.05). Between-group differences were not significant for other variables at the end of the research. In the placebo group, none of the studied biomarkers were altered significantly. Conclusions: Our findings divulge the beneficial effects of carnosine supplementation in improving the antioxidant status and attenuating some of the oxidative stress biomarkers in patients with T2DM making it a useful adjunct therapy.