Metabolic Responses to High-Fat Feeding and Chronic Psychological Stress Combination.

INTRODUCTION: High-fat diet (HFD) consumption and being exposed to daily psychological stress, common environmental factors in modern lifestyle, play an important role on metabolic disorders such as glucose homeostasis impairment. The aim of this study was to investigate the effects of high-fat diet (HFD) and psychological stress combination on metabolic response to chronic psychological stress in male rats.

METHOD: Male Wistar rats were divided into HFD, and normal diet (ND) groups and then into stress and nonstress subgroups. The diets were applied for 5 weeks, and psychological stress was induced for 7 consecutive days. Then, blood samples were taken to measure glucose, insulin, free fatty acids (FFA), and leptin and corticosterone concentrations. Subsequently, glucose-stimulated insulin release from pancreatic isolated islets was assessed.

RESULTS: HFD did not significantly change fasting plasma glucose, insulin and corticosterone levels, whereas increased plasma leptin (7.05 ± 0.33) and FFA (p < 0.01) levels and impaired glucose tolerance. Additionally, HFD and stress combination induced more profound glucose intolerance associated with increased plasma corticosterone (p < 0.01) and leptin (8.63 ± 0.38) levels. However, insulin secretion from isolated islets did not change in the presence of high-fat diet and/or stress.

CONCLUSION: HFD should be considered as an intensified factor of metabolic impairments caused by chronic psychological stress.