Early alterations in vascular contractility associated to changes in fatty acid composition and oxidative stress markers in perivascular adipose tissue.

REBOLLEDO ALEJANDRO; REBOLLEDO OSCAR; MARRA CARLOS ALBERTO; GARCÍA M.E.; ROLDÁN PALOMO A.R.; RIMORINI L.; GAGLIARDINO JUAN JOSÉ

CARDIOVASCULAR DIABETOLOGY

BIOMED CENTRAL LTD

Lugar: New York; Año: 2010 vol. 9 p. 65 - 73

1475-2840

Aim: to test the effect of dietary-induced changes in the fatty acyl composition of perivascular adipose tissue (PVAT) and glucooxidative stress biomarkers upon vascular reactivity. Methodology: adult male Wistar rats were fed (3 weeks) with a commercial diet (CD) supplemented (FRD) or not with fructose (10 % in the drinking water ad-libitum). We measured plasma metabolic parameters, fatty acyl composition of total lipids and oxidative stress biomarkers in aortic PVAT. Vascular contractility was measured in aortic rings sequentially stimulated by 5-HT and high K+-induced depolarization using intact and thereafter PVAT-deprived rings. Results: comparable body weights and plasma glucose levels were recorded in both groups. FRD rats had significantly higher plasma triglyceride, fructosamine and insulin levels, insulin:glucose molar ratio and HOMA-R score. Their PVAT had an increased saturated to mono- or poly-unsaturated fatty acyl ratio, a significant decrease in total superoxide dismutase and glutathione peroxidase activities and total content of glutathione. Conversely, lipid peroxidation (estimated by TBARS), NOx content, and glutathione reductase activitiy were significantly higher. Removal of PVAT produced an increase in contractile force which was significantly smaller in rings from FRD rats. This effect was not longer observed when the two contractions were performed in PVAT-deprived rings. PVAT did not affect depolarization-induced contractions neither in CD nor in FRD rats. Conclusions: FRD induces multiple metabolic and endocrine systemic alterations which also alter PVAT and the vascular relaxant properties of this tissue. The changes in PVAT resemble those measured in abdominal adipose tissue and affect its paracrine modulation upon vascular function.