Participation of grape pomace rich in polyphenols compounds on adipose tissue angiogenesis and inflammation

PERDICARO DJ; PICCOLI P; FONTANA AF; VAZQUEZ PRIETO MA; RODRIGUEZ LANZI MC; MIATELLO RM

Quebec

Conferencia; 8th International Conference of Polyphenols and Health; 2017

Adipogenesis and angiogenesis may counteract adipose dysfunction under exposure to long-term of high-fat diet. On the other hand, polyphenols from grape has been found to exert anti-inflammatory effect on adipose tissue. The aim of this study was to evaluate the effect of malbec grape pomace extract (GPE) on adipose tissue angiogenesis/adipogenesis and inflammation from Spontaneously Hypertensive (SHR) and Wistar-Kyoto (WKY) rats receiving a high-fat diet (HFD). SHR/WKY (n=16) rats were divided into three groups: Control group SHR/WKY (n=4); SHR/WKY-HFD group receiving fat (40% (w/w), (n=6); and SHR/WKY- HFD supplemented with GPE (300 mg/Kg/d) (n=6) for 10 weeks. HF diet consumption led to increased body weight in WKY rats compared to both Ctrl and SHR strain. Also HF consumption led to increased plasma free fatty acid (FFA) concentration in SHR rats compared to Ctrl WKY. Supplementation with GPE significantly decreased plasma triglyceride in WKY rats and FFA concentration in both WKY and SHR rats fed a HF diet. GPE significantly reduced SBP starting at week 5 andincreased HDL cholesterol concentration in HF SHR rats. HF diet significantly increased eWAT weight and adipocyte size in WKY rats, suggestive of hypertrophy. WKY rats supplemented with GPE had smaller adipocytes without changes in adipose weight, suggestive of hyperplasia. On the other hand, HF diet consumption did not affect eWAT weight and the diameter of adipocytes in SHR rats. GPE supplementation led to higher eWAT PPARg protein levels in both SHR and WKY rats and higher mRNA levels in SHR compared to WKY/SHR HF and Ctrl groups. In HF rats increased adipose tissue angiogenesis was evidenced by the expression of vascular endothelial growth factor A (VEGF-A) protein levels in both strains, while VEGF-R2 protein levels were higher only in SHR rats. In addition, GPE supplementation enhanced VEGF-A and VEGF-R2 protein levels in WKY compared to WKY HF and Ctrl rats. In contrast, the VEGF-A mRNA expression was enhanced by GPE in SHR. No differences were observed in PPAR-γ, VEGF-A and VEGF-R2 mRNA expression among WKY rats. HF diet consumption caused higher levels of TNFα and MCP-1 mRNA, and CD68 protein in SHR rats, which was prevented by GPE supplementation. Protein levels of resistin, a pro-inflammatory adipocytokine, were higher in WKY HF and in all SHR groups, while those of Nox4 were higher in the WKY/SHR HF groups. GPE supplementation significantly reduced HFinduced increase of resistin and Nox4 protein in both WKY and SHR strains. Considering these results, supplementation with food rich in bioactive compounds can attenuate adipose tissue inflammation perhaps by its effect on increase adipose tissue angiogenesis and adipogenesis.