An Efficient Model of Non-alcoholic Fatty Liver Disease (NAFLD) Versus Current Experimental Models: Effects of Fructose, Fat, and Carbon Tetrachloride on NAFLD

Abstract

Background: Accumulation of fat in the liver is one of the causes of non-alcoholic fatty liver disease (NAFLD), which affects about 30% of the world's population. Animal models have been useful tools for investigating the mechanisms involved in the etiology of NAFLD and developing new drugs. Objectives: This study aimed to present a new model for the detection of NAFLD in rats. Methods: Forty-eight rats were randomly divided into six experimental groups: (1) control; (2) 45% fructose + 35% olive oil + carbon tetrachloride (FFC1); (3) carbon tetrachloride (1: 4 in olive oil) (C1); (4) carbon tetrachloride (1: 6 in olive oil) (C2); (5) 12.5% fructose + 12.5% olive oil (FF); and (6) 20% fructose + carbon tetrachloride (1: 4 in olive oil) (FC1). Blood samples were taken in three steps, and liver tissue was dissected at the end of the sixth week for histopathological assessments. Results: After six weeks, the alanine transaminase (131.63 ± 1.51), aspartate transaminase (275 ± 1.0), and gamma-glutamyl transferase (4.30 ± 0.1) levels increased significantly in the C1 group (P < 0.05). The serum lipid profile showed significant changes in all groups compared to the controls (P < 0.01). According to the histological results, all experimental groups, except the C2 group, showed symptoms of NAFLD; nevertheless, a higher NAFLD Activity Score (NAS) was found in the C1 group, followed by the FC1 group, compared to the other groups. Conclusions: The present results revealed that injection of 0.1 mL/kg of carbon tetrachloride (C1 group), alone or along with a diet containing 20% fructose (FC1 group), provided useful animal models of NAFLD, although carbon tetrachloride injection alone is the most effective model in inducing NAFLD model that can be used as a new strategy in nutritional and pharmacological studies.