INVESTIGADORES
CHOI Marcelo Roberto
congresos y reuniones científicas
Título:
High fat diet and fructose overload modify aortic vascular morphology and type C natriuretic peptide expression in rats
Autor/es:
LEE HJ; CANTÚ SM; ÁLVAREZ PRIMO M; DONOSO AS; CAO G; CHOI MR; PUYÓ AM
Lugar:
Rosario
Reunión:
Encuentro; Reunión Anual SAFIS, Hotel Plaza Real, Rosario; 2019
Institución organizadora:
Sociedad Argentina de Fisiología
Resumen:
Metabolic and cardiovascular diseases are closely linked. Experimental models such as high-fat diet (HF) and/or fructose-overload (F) in rats resemble human metabolic syndrome (MS). Type C natriuretic peptide (CNP) produced in endothelial cells exert vasodilatory effects and a variety of metabolic actions. Therefore, we analyze the effects of F, HF diets and the combination of both (HF+F) on aortic vascular morphology and CNP immunoreactivity. Four groups of male Sprague-Dawley rats were studied for 9 weeks: control (C): standard diet (SD) and tap water to drink; fructose-overloaded (F): SD and fructose solution (10% w/v) to drink; high-fat diet (HF): 50% (w/w) bovine fat added to SD and water to drink; fructose plus high-fat diet (HFF), both treatments. We evaluated CNP in aorta tissue by immunohistochemistry, expressed as integrated optical density (IOD), and aortic morphology measuring the wall thickness/lumen diameter ratio. Visceral adiposity index was calculated as mesenteric vascular bed fat weight/body weight x 100. All groups with dietary modification showed elevated insulinemia (ng/ml, F: 4.3±0.5, HF: 5.3±0.4, HFF: 4.3±0.2, vs C: 1.2±0.1; p<0.01), triglyceridaemia (mg/dl, F: 163±10, HF: 170±9, HFF: 188±16, vs C: 65±9; p<0.01), systolic blood pressure (SBP, mmHg, F: 149±1, HF: 151±1, HFF: 153±1, vs C: 119±2; p<0.01), visceral adiposity index (VAI, %, F: 1.1±0.1; p<0.05, HF: 1.8±0.1, HFF: 1.8±0.1, vs C: 0.7±0.1; p<0.01) and aortic wall thickness/lumen diameter ratio (um/mm, F: 62.6±3.1, HF: 63.3±2.6, HFF: 64.0±3.0, vs C: 44.7±1.3; p<0.01) compared to control group. This ratio also positively correlates with SBP (r=0.91, p<0.05) and VAI (r=0.82, p<0.05). Besides, the modified diets decrease CNP immunoreactivity in the aortas of all experimental groups (DOI, F: 3,19±0,40, HF: 4,82±0,71; p<0.05, HFF: 2,29±0,03 vs C: 7,72±0,26; p<0.01). In conclusion, HF, F and HF+F diets increased adipose tissue and produced vascular wall modifications, increasing wall thickness and diminishing CNP expression. All these alterations would contribute to the development of visceral obesity-related hypertension directly through the reduction of vasodilatory mechanisms.