Grape pomace extract, rich in polyphenols, induced beige cells in white adipose tissue in spontaneously hypertensive rats and in 3T3-L1 adipocytes

PERDICARO DAHIANNE; CECILIA RODRIGUEZ LANZI; ARIEL RAMON FONTANA; ANDREA ANTONIOLLI

Quebec

Congreso; 8th Interantional Conference in Polyphenols and Health; 2017

This study investigated the effects of a grape pomace extract (GPE), rich in polyphenols, on brown-like adipocytes induction in epididymal white adipose tissue (eWAT) from spontaneously hypertensive rat (SHR) fed a high-fat diet and in 3T3-L1 adipocytes. Supplementation with GPE (300 mg/kg body weight/day) increased proteins involved in adipose tissue ?browning? (PGC-1, PPARγ, UCP-1) in eWAT from SHR but not from WKY rats. In primary cultures of newly differentiated SHR adipocytes, GPE enhances UCP-1 protein levels, while it significantly decreased upon treatment with SB203580 (p38 inhibitor) or U0126 (ERK inhibitor). This suggests that GPE enhances UCP-1 expression, in part via p38 and ERK. In addition, in 3T3-L1 adipocytes treated with palmitate GPE (30 M) activated the β-adrenergic signaling cascade (PKA, AMPK, p38, ERK), which is involved in mitochondrial biogenesis (UCP-1, PPARγ and PGC-1α) and in fatty acid oxidation (ATGL). These effects were comparable to those exerted by the flavanol (-)-epicatechin or the flavonol quercetin (1 µM), some of the main phenolic compounds found in GPE. These results suggest that GPE consumption enhances brown-like cells number in eWAT. This is of significance in the utilization of winemaking residues, rich in bioactive compounds, to mitigate the adverse effects of obesity or related conditions.