The usefulness of short-term high-fat/high salt diet as a model of metabolic syndrome in mice

Abstract

Diabetic cardiomyopathy (DC) describes diabetes-associated changes in the structure and function of myocardium that are not directly linked to other factors such as hypertension. Currently there are some models of DC; however, they take a large time period to mimic key features. In the present study, we investigated the effects of a short-term high-fat/high salt diet (HFHS) treatment on myocardial function and structure, and vascular reactivity in C57BL/6 male mice. After 14 weeks HFHS induced hypertension (MAP = 144.95 ± 16.13 vs 92.90 ± 18.95 mm Hg), low glucose tolerance (AUC = 1049.01 ± 74.79 vs 710.50 ± 52.57 a.u.), decreased insulin sensitivity (AUC = 429.83 ± 35.22 vs 313.67 ± 19.55 a.u.) and increased adiposity (epididymal fat weight 0.96 ± 0.10 vs 0.59 ± 0.06 OW/BW × 10²), aspects present in metabolic syndrome. Cardiac evaluation showed diastolic dysfunction (E/A ratio = 1.20 vs 1.90 u.a.) and cardiomyocyte hypertrophy (cardiomyocyte area = 502.82 ± 31.46 vs 385.58 ± 22.11 μm²). Lastly, vascular reactivity was impaired with higher contractile response (136.10 ± 3.49 vs 120.37 ± 5.43%) and lower response to endothelium-dependent vasorelaxation (74.01 ± 4.35 vs 104.84 ± 3.57%). In addition, the diet was able to induce an inward coronary remodeling (vascular total area: SCNS 6185 ± 800.6 vs HFHS 4085 ± 213.7 μm²). Therefore, we conclude that HFHS short-term treatment was able to induce metabolic syndrome-like state, cardiomyopathy and vascular injury working as an important tool to study cardiometabolic diseases.

Keywords: Animal model; Heart; Metabolic syndrome; Mice; Obesity.