Introduction of high-fat and very-high-fat diets associated with fructose drink in critical development periods causes cardiovascular damage in rats at the beginning of adult life.

OBJECTIVES: Exposure to an obesogenic environment at critical stages of human development may lead to cardiovascular damage during early adulthood, such as left ventricular hypertrophy (LVH). The objective of this study is to investigate whether the consumption of diets with different levels of fat associated with fructose drink, introduced to newly weaned rats, leads to cardiovascular damage. METHODS: Male Wistar rats (age 21 d) were divided into the following groups: Control (C group) fed an American Institute of Nutrition 93G diet (16.3 % kcal of lipid); high-fat diet (HF group: 45% kcal of lipids), and very-high-fat diet (VHF group: 60% kcal of lipids). The HF and VHF groups also received a fructose solution (10%) for hydration. RESULTS: After 70 d, the animals in the HF and VHF groups presented with cardiovascular damage as a comorbidity of obesity, with increased creatine kinase-MB levels, high heart and left ventricle (LV) mass, and an increase in the LV:tibia ratio. The positive correlation was observed between serum leptin levels and LV mass. In addition, the signal transducer and activator of transcription 3 content in LV was lower. CONCLUSIONS: The administration of diets with different fat and carbohydrate contents associated with fructose drinks introduced to newly weaned rats leads to LVH during early adulthood. The data suggest that the change in leptin-signal transducer and activator of transcription 3 pathway signaling in the groups is related to the occurrence of LVH.

High-fat diet and fructose drink introduced after weaning rats, induces a better human obesity model than very high-fat diet.

In the present study, we associated a high-fat diet (HF group: 45% kcal from lipids) or very high-fat (VHF group: 60% kcal from lipids) diet with a fructose drink (10% fructose) for hydration. Normal rat chow that received the control diet (content 16.3% kcal from lipid-AIN93G) and water. The treatments were introduced soon after weaning and were administered for 70 days. We aimed to compare HF and VHF groups and find which acts as a better model mimicking human obesity. Body mass gain, final body weight, adipocyte area in inguinal depots, visceral and subcutaneous adipose depots, serum triacylglycerol, and VLDL-c were all higher in the HF group, followed by the VHF group, compared to the C group. Only the HF group showed hyperinsulinemia and hyperleptinemia and higher total caloric intake, Lee index, HOMA2-IR, and total cholesterol. Serum TNF-α and IL-6 levels were lower in the HF and VHF groups than in the C group at the end for 70 days. In Summary, the HF (45%) diet administered with fructose induced a higher similarity of metabolic and hormonal alterations associated with human obesity. PRACTICAL APPLICATIONS: High intake of lipids with sugary drinks has been associated with obesity and its comorbidities. Although a diet with 45% or 60% of lipids is considered hyperlipidic, they are different in their effects on eating behavior and also probably from a metabolic point of view. Common sense is that the reduction in intake of lipids is favorable to health. Our study shows that this is not wholly true, and this information contributes to the guidelines for the treatment of obesity. In addition, the scientific literature on the subject has shown the most diverse results and also the use of experimental models with few similarities with human obesity. Our findings can contribute as a good model of obesity initiated during childhood to investigate possible using nutritional strategies, or the adoption of ergogenic nutritional resources in future studies, for example.