Development of metabolic syndrome by increasingly fructose-enriched water in Wistar rats

Several studies have shown that excessive fructose consumption increases the risk of developing metabolic syndrome (MS), which can lead to diabetes mellitus. This study aimed to evaluate the metabolic and histological abnormalities accompanying MS induced by progressive high fructose diet (HFr) in Wistar rats. Twelve Wistar rats were used, divided into two groups (n = 6) (NC and HFr). They were fed a HFr with daily administration of increasingly higher doses of fructose solutions (dose 1 = 20% from week 1 to 4, dose 2 = 25% from week 5 to 8 and dose 3 = 30% from week 9 to 12 ), during which body weight and blood glucose were measured, while an oral glucose tolerance test (OGTT) was performed, it's glucose, triglyceride, and total cholesterol concentrations were determined, and pancreatic, liver, and kidney tissues were studied at the end of the experiment. Daily administration of increasingly high doses of fructose caused body weight increase, manifested by a highly significant difference in body weight, a metabolic abnormality, differences in fasting blood glucose (hyperglycaemia), plasma concentration of glucose, glucose intolerance, and by a very significant increase of total cholesterol and triglycerides levels in blood (hyperlipidaemia) between HFr and NC groups of rats. Histopathological study showed a slight swelling of the hepatocytes and a narrowing of the blood sinusoids, as well as an inflammatory infiltration of the portal space in the hepatic section of HFr group, no morphological alterations, necrosis, or steatosis in the pancreatic and renal sections of HFr group of rats. A twelve-week HFr diet can cause some abnormalities in the liver tissue, in carbohydrate and lipid metabolism in Wistar rats without damaging their pancreas and kidneys, which may be explained by the fact that metabolic abnormalities can precede histological lesions.