Vitamin D3 Supplementation Could Improve the Effect of Exercise Training on Type 2 Diabetes -Induced Metabolic Disorders via BDNF/Irisin Axis in Elderly Women

Abstract

Abstract Objectives Metabolic disorders are commonly linked to the process of aging and menopause. It is assumed that exercise and vitamin D (VitD) can have positive effects on the body, specifically via changes in irisin and brain-derived neurotrophic factors (BDNF) levels. This study aimed to investigate the concurrent effect of VitD3 and exercise training on insulin resistance, memory performance, irisin, and serum BDNF in postmenopausal women with diabetes. Methods In the present study, forty participants were randomly assigned into four groups of placebo, VitD3, placebo + combined exercise, and VitD3 + combined exercise (n = 10 for each group). The exercise groups received the related treatments for 8 weeks. Before the implementation of interventions and 24 hours after the last session, short-term/working memory performance, insulin, homeostatic model assessment-insulin resistance (HOMA), fasting blood sugar (FBS), cholesterol, low/high-density lipoprotein-cholesterol (LDL/HDL), triglyceride (TG), VitD3 levels, fasting serum BDNF and irisin were measured. Results Our data indicated the highest reduction in HOMA, insulin, cholesterol, TG, LDL (P < 0.001), FBS (P < 0.01), but the highest amount of increase in irisin and BDNF (P = 0.007; P = 0.004, respectively) and Digit Span Forwards and Backwards tests (P = 0.002 and P = 0.006, respectively) in VitD3 + combined exercise compared with the placebo group. Conclusion Our findings showed that the combination of VitD3 supplementation and aerobic training/MSROM, compared with mono-therapy can effectively attenuate insulin resistance, cardiovascular risk factors, and improve memory performance in postmenopausal women diagnosed with type 2 diabetes, in part due to the signaling of BDNF and irisin.