Metabolic Consequences of Polycystic Ovary Syndrome and Their Impact on Hepatic Function in High Fat Diet-Fed Rats: Potential Role of Moderate Intensity Exercise

Polycystic ovary syndrome (PCOS) is associated with a heightened risk for various metabolic comorbidities, including glucose intolerance, type II diabetes mellitus, dyslipidaemia, metabolic syndrome, hepatic steatosis and non-alcoholic fatty liver disease (NAFLD) Objectives: the current study aims to elucidate the metabolic consequences of PCOS, with a particular focus on insulin resistance and dyslipidaemia, and their impact on hepatic function, with or without high fat diet feeding, and to investigate the potential therapeutic role of moderate-intensity exercise in mitigating these PCOS-associated metabolic and hepatic complications. For this, 55 adult female Wistar albino rats were divided into 5 equal groups: Control group, polycystic ovary syndrome group (PCO), high fat diet fed polycystic ovary syndrome group (HF-PCO), exercise-treated polycystic ovary syndrome group (PCO-EX), and high fat diet fed exercise-treated polycystic ovary syndrome group (HF-PCO-EX). At the end of the study period (8 weeks), anthropometric measures were taken. Insulin resistance, lipid profile and liver enzymes activity were also assessed and serum estradiol, testosterone, luteinizing hormone (LH), resistin and adiponectin levels were measured. Histopathological examination of ovarian and hepatic tissues was also performed. The results obtained demonstrated that glycaemic parameters significantly implied insulin resistance which was associated with a significant increase in serum triglycerides (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and atherogenic index (AI). On the other hand, there was a significant decrease in high density lipoprotein cholesterol (HDL-C) levels in the PCO and HF-PCO compared to the control group. Also, the activity levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyl transferase (GGT) as well as serum concentration of testosterone, LH and resistin were all significantly increased while serum concentration of estradiol, adiponectin and adiponectin/resistin ratio (A/R) were significantly decreased. Swimming exercise was able to reduce serum testosterone and LH concentration levels and to elevate serum estradiol concentration and to improve all the metabolic parameters compared to their corresponding non-exercised groups through reduction of the proinflammatory cytokine resistin and elevation of adiponectin and A/R ratio. Histopathological analysis corroborated these findings revealing minimal inflammatory infiltration, apoptosis, and steatosis in the livers of exercised animals. These data allowed us to conclude that moderate intensity exercise notably improved insulin resistance and lipid metabolism, and mitigated hepatic effects through reducing the activity of liver enzymes and the levels of inflammatory cytokines, potentially preventing the development of non-alcoholic fatty liver disease (NAFLD) in PCOS rats, regardless of dietary fat content.