Morphofunctional state of the liver of male Wistar rats during diet-induced obesity and its correction

Nonalcoholic fatty liver disease is the most common pathological condition inherent in obesity, which is associated with excessive accumulation of lipid droplets in hepatocytes, which, in turn, leads to the impaired functioning of the organ.

The aim of the study is to investigate the effect of diet-induced obesity, as well as variants of its correction on morphofunctional characteristics of the liver tissue and biochemical indices of blood serum of male rats.

The experiments were carried out on sexually mature male Wistar rats. The experiment consisted of two stages of 8 weeks each: 1) modeling obesity using a high-caloric diet (HCD); 2) obesity correction with the evaluation of the contribution of several experimental approaches: abandonment of HCD with a transition to a standard balanced diet and moderate physical activity in the form of running on a treadmill against the background of different caloric intakes.

Keeping the rats for 16 weeks on HCD led to the formation of visceral obesity, fatty liver dystrophy, dyslipidemia, and disbalance of enzymatic processes – hyperbilirubinemia on the background of the reduced activity of aspartate aminotransferase and alanine aminotransferase in blood serum. The histoarchitectonics of the liver was partially restored with the preservation of inflammatory infiltration of the organ upon return to the standard diet. A return to the standard diet promoted a partial restoration of the liver histoarchitectonics with the preservation of inflammatory infiltration of the organ. When switching to a standard diet in combination with the moderate physical activity, a more pronounced restoration of the liver histostructure and signs of the active regeneration of the organ were observed.

The most complete variant of correction of fatty hepatosis is the transition to a balanced diet in combination with the moderate physical activity.

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