Modification of a model of non-alcoholic fat liver disease in rats with a сombination of a hypercaloric diet and hypodynamia

Abstract

Introduction. Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in the world, and non-alcoholic steatohepatitis is the second most common cause of liver transplantation in the adult population. An urgent task is to find and develop an optimal model of NAFLD in laboratory animals, which would reproduce all the features of this disease in the clinic.Aim. Modification of the NAFLD model in laboratory animals (rats), which allows the obtained data to be transmitted to humans as fully as possible.Materials and methods. The study was conducted on 52 outbred white male rats of the same age. As the basis of the model, a hypercaloric high-fat diet was used with the addition of food appeal enhancers (sodium glutamate and liquid shrimp extract) and for the first-time conditions of hypodynamia were used – restriction of the motor activity of animals using specially designed cells, in which an individual 11 × 18 cm cell was allocated for each individual. The duration of the study was 12 months. In the course of the experiment, body weight, physical performance, biochemical parameters of blood serum and urine in dynamics were assessed, and lethality was recorded. After the end of the study, the mass of internal organs, visceral and epididymal fat was analyzed, and a histological examination of the liver was performed.Results and discussion. In the course of the experimental study, the development of NAFLD in rats of the control group of animals was histologically confirmed. A high mortality rate was revealed in the group of animals with pathology. Compared with animals of the intact group, a statistically significant increase in their body weight, liver weight, visceral and epididymal fat, a decrease in physical performance, disturbances in lipid, carbohydrate and protein metabolism were revealed, as well as signs of deterioration of the protein synthesis and excretory functions of the liver.Conclusion. A number of advantages of the NAFLD model with a combination of a hypercaloric diet and hypodynamic conditions were revealed, including the similarity of the conditions for the formation and pathogenesis of the disease in experimental animals and humans, which ensures the adequacy of data translation from preclinical practice to clinical practice.

Keywords

• non-alcoholic fatty liver disease
• hypercaloric diet
• physical inactivity
• attractants
• sodium glutamate
• physical performance
• visceral fat
• epididymal fat