RESUMEN
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 Aß-42 and glucose, histological changes by toluidine blue, and immunohistochemistry for brain Aß-42 and tau-positive cells. Results: Serum glucose, FFA, TG, cholesterol, LDL, brain Aß-42, brain glucose, the number of hippocampal dark and degenerated cells, and brain Aß-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.
RESUMEN
Background: Cadmium (Cd) is a toxic heavy metal used in many industries. Since the second half of the 20th century, legislation on Cd use was put to limit the exponential rise in its environmental levels. This study aimed to investigate Cd's functional and ultrastructural changes on rats' reproductive systems and the role of Zingiber officinale (Ginger) in protecting against Cd-induced toxicity. Methods: Thirty adult male albino rats were randomly assigned into three equal groups (n = 10); control, Cd-exposed/untreated, and Cd-exposed/Gin-treated. Rat testes were weighed, and testicular tissue sections were examined under the electron microscope. Semen analysis, morphological examination of spermatozoa, and serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone were measured. In addition, testicular tissue homogenates were analyzed for malondialdehyde (MDA), nitric oxide (NO), and reduced glutathione (GSH) levels. Results: Cd-induced significant reduction in the mean testicular weight and GSH levels and plasma testosterone, LH and FSH levels with a concomitant increase in testicular MDA and NO levels. There was also a deterioration in semen analysis parameters and spermatozoa morphology, with testicular structural damage in the form of architecture distortion and necrosis of seminiferous tubules and testicular interstitial cells. Daily administration of ginger for 4 weeks protected against CD-induced toxicity, preserving tissue architecture, improved plasma levels of testosterone, LH and FSH and testicular levels of GSH, and reduced testicular levels of MDA, NO. Conclusion: Ginger has a protective effect on Cd-induced deterioration of testicular tissue's structural and functional integrity by improving testicular tissue antioxidant capacity and steroid production, which ameliorates sex hormone levels in the blood.