Effects of quercetin and low-level laser on oxidative and inflammatory factors among patients with type 2 diabetes mellitus and mild cognitive impairment

Background: Unmanaged type 2 diabetes mellitus has dangerous consequences, such as neuropathy. Oxidative stress and inflammatory factors play an important role in the development of diabetic neuropathy. Diabetics are prone to mild cognitive impairment, which is a neurological disease. The aim of this study was to investigate the effects of quercetin as a functional food and oxidative agents and inflammatory factors of low-level laser.Methods: In this study, 60 elderly volunteers were selected: 30 normal as a control group and 30 with type 2 diabetes mellitus and mild cognitive impairment. The average age was 75 years old. Groups of diabetic patients were examined for changes in glucose levels, oxidants, antioxidants and inflammatory factors before and after treatment with quercetin and low-level laser therapy–green laser diode with a wavelength of 532 nm at 100 mw and compared with the control group. Changes in the levels of biochemical parameters were performed according to the instructions of the relevant kits. Results: The results of the obtained data analysis showed that there was a significant difference (P value < 0.05) in the levels of glucose, hydrogen peroxide, advanced glycation end-products, malondialdehyde, oxidized-low density lipoprotein, paraoxonase, lipoprotein lipase, and inflammatory factors including TNF-α, interleukin-1 alpha and interleukin-1 beta between diabetic samples before and after treatment with quercetin and laser from control subject samples. There was no significant difference (P value > 0.05) in inflammatory factors between quercetin-treated, laser-treated and both quercetin and laser treated groups. The synergistic effect of quercetin and laser between the quercetin and laser treated group and the untreated group on changes in the levels of biochemical parameters was observed significantly only in advanced glycation end-products, malondialdehyde, oxidized-low density lipoprotein, and paraoxonase.Conclusion: The results showed that quercetin, laser, and their synergistic effect can play a role in reducing some oxidant factors.Keywords: Quercetin, Low-level laser, Inflammatory factors, Oxidative factors, Diabetes mellitus