Effects of diet-induced obesity and its correction on sex hormone levels and behavioral featurеs of male Wistar rats

Obesity causes a wide range of pathophysiological consequences in the body, affecting the sphere of hormonal and psycho-emotional regulation. The aim of the study is to investigate the effect of a high-calorie diet on the development of obesity, reproductive status hormone levels and behavioral features of male Wistar rats, as well as the possibility of normalizing the identified shifts with non-medicinal options for obesity correction. Experiments were performed on 80 sexually mature male Wistar rats for 16 weeks and included 6 groups of animals, taking into account the diet (standard vivarium diet, highcalorie diet and transition from a high-calorie diet to a standard diet at the 2nd stage of the experiment) with or without the moderate physical activity in the form of treadmill running at the 2nd stage – the last 8 weeks of the experiment. A longterm high-caloric diet (16 weeks) caused visceral obesity, elevated glucose, cholesterol and triglyceride levels, dramatically decreased serum testosterone and estradiol levels, and depression manifestations in the Porsolt test in male Wistar rats. Successful correction of obesity, metabolic shifts and depressive behavior in rats was achieved by switching to a balanced diet during the last 8 weeks of the experiment. Normalization of testosterone and estradiol levels against the background of an increased serum luteinizing hormone level occurred in rats receiving a high-calorie diet (16 weeks) with the connection of physical exercise during the last 8 weeks of the experiment. Complex correction of obesity, which included the transition to a standard diet and exercise during the last 8 weeks of the experiment, led to a dramatic 2-fold increase in testosterone levels compared to control and a hyperactive phenotype in male Wistar rats. There is a close relationship between the depression development and testosterone levels in obesity and its correction.

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