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

Abstract

AimTo test the early effect of fructose-induced changes in fatty acid composition and oxidative stress markers in perivascular adipose tissue (PVAT) upon vascular contractility.MethodsAdult male Wistar rats were fed a commercial diet without (CD) or with 10% fructose (FRD) in the drinking water for 3 weeks. We measured plasma metabolic parameters, lipid composition and oxidative stress markers in aortic PVAT. Vascular contractility was measured in aortic rings sequentially, stimulated with serotonin (5-HT) and high K+-induced depolarization using intact and thereafter PVAT-deprived rings.ResultsComparable body weights were recorded in both groups. FRD rats had increased plasma triglyceride and fructosamine levels. Their PVAT had an increased saturated to mono- or poly-unsaturated fatty acid ratio, a significant decrease in total superoxide dismutase and glutathione peroxidase activities and in the total content of glutathione. Conversely, lipid peroxidation (TBARS), nitric oxide content, and gluthathione reductase activity were significantly higher, indicating an increase in oxidative stress. In aortic rings, removal of PVAT increased serotonin-induced contractions, but the effect was significantly lower in rings from FRD rats. This effect was no longer observed when the two contractions were performed in PVAT-deprived rings. PVAT did not affect the contractions triggered by high K+-induced depolarization either in CD or FRD rats.ConclusionsFRD induces multiple metabolic and endocrine systemic alterations which also alter PVAT and the vascular relaxant properties of this tissue. The changes in PVAT would affect its paracrine modulation of vascular function.

Similarity of mouse perivascular and brown adipose tissues and their resistance to diet-induced inflammation

“…A second possibility is that the fatty acid species released by BAT and PVAT may also afford an anti-inflammatory effect. The ratio of saturated to polyunsaturated fatty acids has been shown to increase in the VAT and abdominal PVAT of high-fructose fed rats (34). Thus under these conditions WAT may release relatively higher levels of saturated fatty acids, which may be more active in stimulating macrophage chemotaxis (23, 37).…”

Perivascular adipose tissue: more than just structural support

“…By creating a VSMC-adipocyte co-culture, these authors demonstrated a decrease in AMPK phosphorylation and an increase in mTOR phosphorylation in VSMCs co-cultured with adipocytes from HFD treated rats (71). Finally, the role of fatty acid (FA) composition was highlighted in a recent article of fructose-fed rat model of metabolic syndrome, in which the PVAT anticontractile effect was diminished in aorta and the ratio of saturated to mono or polyunsaturated FA was increased, antioxidant enzyme expression was decreased and markers of oxidative stress were increased in PVAT (76). In another study, the increased norepinephrine-induced contraction in fructose-fed rats was corrected with losartan in both the presence and absence of PVAT(77).…”

Perivascular Fat and the Microcirculation: Relevance to Insulin Resistance, Diabetes, and Cardiovascular Disease

“…In spontaneously hypertensive rats [126] and insulin-resistant fructose-fed rats [127], the relaxing effect of PVAT on mesenteric arteries was found to be impaired. At present, the nature of the ADRFs is not fully clear, although angiotensin 1–7 [115], adiponectin [25••], and hydrogen sulfide [128] have been mentioned as ADRFs.…”