Partially hydrogenated vegetable oil containing 5% trans fats when combined with fructose exacerbates obesity and non-alcoholic fatty liver disease in rats

Abstract

The aim of this study is to test the hypothesis that feeding trans fatty acids (TFA) (5%) along with fructose exacerbates obesity and non-alcoholic fatty liver disease (NAFLD) in rats. Male Wistar rats were randomized into four groups, i.e., standard diet, 5% TFA + standard diet, fructose + standard diet, and TFA + fructose + standard diet. All the diets were provided for 16 weeks. The body weight, body mass index, calorie intake, adiposity index, and liver index were determined. Serum glucose, insulin, lipid profile, and liver enzymes were estimated. Liver lipids, markers of oxidative stress, inflammation, and collagen were estimated in the liver. The histopathological evaluation of the adipose tissue and liver were carried out. TFA + standard diet caused an increase in body weight while TFA + fructose + standard diet caused significant body weight gain, adiposity index, and hypertrophy of adipocytes. TFA + fructose + standard diet caused insulin resistance and dyslipidemia in the rats. Rats in the TFA + standard diet group showed marked hepatic steatosis and an elevation in alanine aminotransferase, while those in the TFA + fructose + standard diet group showed oxidative stress, inflammation, and fibrosis in the liver. Feeding of TFA at a concentration of 5% along with the standard diet resulted in an increase in the body weight and hepatic steatosis, but the addition of fructose to 5% TFA and standard diet resulted in obesity and non-alcoholic steatohepatitis. Thus, the reduction in TFA content of foods must be accompanied by a significant decrease in the fructose intake in order to protect against obesity and NAFLD.