Effect of diet-induced obesity and non-drug options of its correction on the functional and morphological liver characteristics in female Wistar rats

A nonalcoholic fatty liver disease is one of the unfavorable consequences of obesity. However, experimental studies on the mechanisms of this pathology development are being carried out mainly on male rodents, and the data on the development of fatty hepatosis in females are insufficient. The aim of the study was to investigate the effect of diet-induced obesity and non-drug options for its correction on the morphological liver characteristics and liver metabolic parameters in female Wistar rats. Experiments were conducted on sexually mature female Wistar rats and included the study of morphological and biochemical parameters of the liver functional state in animals kept on standard diet (StD, 16 weeks), on a high-calorie diet (HCD, 16 weeks) when switching to a standard diet (HCD/StD, 8/8 weeks), when the physical activity in the form of treadmill running was included (StD + running, HCD + running and HCD/StD + running, 8/8 weeks). Long-term use of HCD in female rats caused visceral obesity, liver fatty dystrophy with disruption of organ histoarchitectonics, shifts in hepatic metabolism and increased lipid peroxidation. Correction of diet-induced obesity by switching to StD led to a complete or partial normalization of the studied indices. In the “HCD + running” group, metabolic disorders are often more pronounced than in the “HCD” group. The transition to HCD/StD + running promoted the most complete restoration of metabolism and histostructure of the liver with regeneration signs of the organ. Thus, an optimal correction of visceral obesity, fatty liver dystrophy and its metabolism is impossible without diet normalization in female Wistar rats. An additional regenerating effect with respect to the liver histostructure is achieved with a combined variant of correction ‒ transition to a balanced diet and moderate physical activity.