Inflammatory biomarkers, antioxidant enzyme activities, and oxidative stress in Iranian male patients with type 2 diabetes mellitus: Effects of eicosapentaenoic acid and vitamin C supplementation

Eicosapentaenoic acid (EPA) is the principal ω-3 fatty acid in marine oils. Significant differences have been reported in the serum levels of inflammatory biomarkers, malondialdehyde (MDA), and antioxidant enzymes activity between diabetic patients and controls after supplementation with ω3 fatty acids and antioxidants. Therefore, the aim of this study was to determine the effects of EPA and/or vitamin C, as an antioxidant, on serum levels of interleukin (IL)-6, tumor necrosis factor alpha (TNF-α), MDA, and glutathione reductase activity in type 2 diabetic Iranian males. METHODS: This study was performed on 65 men with type 2 diabetes who aged 33-63 years. Venous blood samples were obtained from all participants at 8:00-9:00 a.m. after 10 hours of fasting, at the baseline and after the intervention. Subjects received 500 mg EPA and/or 200 mg vitamin C or placebo depending on their groups. For eight weeks, 15 participants received EPA supplements with vitamin C (Group 1), 16 took EPA supplements and vitamin C placebo (Group 2), 17 took EPA supplement placebo and vitamin C (Group 3), and 17 received EPA supplement placebo and vitamin C placebo (Group 4), daily. RESULTS: There were significant falls in TNF-α levels in Groups 1 and 2 (p < 0.05) and in MDA in Group 3 (p < 0.05). On the other hand, a significant increase was observed in MDA in Group 2 (p < 0.01) and in glutathione reductase activity in Groups 1 and 3 (p < 0.05). Moreover, according to Tukey's test, there were significant differences in IL-6 (p < 0.01) and glutathione reductase activity (p < 0.05) between Group 4 and other groups. Meanwhile, Tukey's test showed that TNF-α was significantly different between Group 1 and other groups (p < 0.01), Groups 2 and 3 (p < 0.05), and Groups 2 and 4 (p < 0.05). Finally, there were significant differences in MDA levels between Groups 1 and 2 (p < 0.01), Groups 1 and 4 (p < 0.05), Groups 2 and 3 (p < 0.05), Groups 2 and 4 (p < 0.05), and Groups 3 and 4 (p < 0.05) after 8 weeks of intervention. CONCLUSIONS: In summary, it is concluded that eight weeks of EPA + vitamin C supplementation improved inflammation and antioxidant status in male type-2 diabetic patients.