Comparing prophylactic effect of exercise and metformin on cognitive brain functions in rats with type 3 diabetes mellitus

Abstract

Introduction: Type 2 diabetes mellitus (DM) and Alzheimer's disease (AD) are two major medical conditions that constitute a significant financial burden on most healthcare systems. Due to AD sharing "insulin resistance" mechanistic features with DM, some scientists have proposed "type 3 DM" terminology for it. This study aims to compare the prophylactic effect of exercise and metformin on cognitive brain functions in rats with type 3 DM. Material and methods: Two groups of rats were included in the study: the control group (n = 15) and the streptozotocin-induced type 2 diabetic group (n = 45). The diabetic group was subdivided into three equal subgroups: a sedentary non-treated diabetic group, an exercised group, and a metformin-treated group. We estimated step-down avoidance task latency, serum glucose, insulin, free fatty acids (FFA), cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and triglycerides (TG), brain Aβ-42 and glucose, histological changes by toluidine blue, and immunohistochemistry for brain Aβ-42 and tau-positive cells. Results: Serum glucose, FFA, TG, cholesterol, LDL, brain Aβ-42, brain glucose, the number of hippocampal dark and degenerated cells, and brain Aβ-42 and tau-positive cells, were all significantly lower. In contrast, serum insulin and HDL, the number of hippocampal granular cells, and latency of the step-down avoidance task were significantly higher in exercised and metformin-treated groups compared to the diabetic group. There were significantly higher values of serum insulin and brain/plasma glucose ratio and number of brain tau-positive cells in the metformin-treated group than in the exercised group. Conclusions: We can conclude that exercise can be as effective as metformin regarding prophylaxis against the deleterious effects of type 3 DM on cognitive brain functions.

Combined Ursolic Acid and Resistance/Endurance Training Improve Type 3 Diabetes Biomarkers-Related Memory Deficits in Hippocampus of Aged Male Wistar Rats

“…These insulin-induced molecular dysregulations result in learning and memory deficits, as well as general impairment of cognitive functions. [ 34 ]…”

“…Regular physical exercise induced a significant increase in the pancreatic islet size and insulin secretion. [ 34 ]…”

Possible Protective Effect of Each of Omega-3 PUFA and Leptin on Indomethacin-Induced Gastric Ulcer in Rats with type II DM

“…ulcer: indomethacin (18 mg/kg, orally, single dose), dissolved in distilled water and suspended in 2% gum acacia as the vehicle was used to induce ulceration [21]. Two days after indomethacin administration, rats were sacrificed by the CO2 euthanasia method [23].…”

“…That is why our study aimed to investigate their potential protective effects in preventing indomethacininduced gastric ulcers in streptozotocin-induced diabetic rats. PUFA for the study period [21].…”

Current Perspectives Regarding The Effects of Muscular Exercise on Neurological Disorders: A Literature Review

“…Combining a regular exercise program with vitamin supplementation, [35] or with pharmacological intervention, [36] is considered a potential, effective and novel line for treating Alzheimer's disease, as evidenced by the improved histopathological picture and biochemical markers of the brains of Alzheimer's rats.…”