Effect of Dietary Wine Pomace Extract and Oleanolic Acid on Plasma Lipids in Rats Fed High-Fat Diet and Its DNA Microarray Analysis

Abstract

The aim of this study was to evaluate the concentration of oleanolic acids (OA) in pomace, a winemaking byproduct, and its influence on the levels of plasma lipids in rats fed a high-fat diet and on hepatic gene expression using DNA microarray analysis in vivo. HPLC analyses of pomace ethanol extract (PEE) revealed a high amount of OA ranging from 4 to 11 g/100 g. Male Sprague-Dawley rats were fed a normal-fat diet (NF group), a high-fat diet with 21% lard (HF group), a high-fat diet with 0.05% OA (OA group, 50 mg/kg/day), or a high-fat diet with 0.45% PEE (PEE group, 450 mg/kg/day). Plasma triacylglycerol and phospholipid concentrations were significantly lower in the OA and PEE groups than in the HF group. The microarray analysis of hepatic mRNA revealed reduced expression levels of lipogenic genes including acetyl-CoA carboxylase and glycerol-3-phosphate acyltransferase, probably resulting from the suppression of transcription factor Srebf1 expression. Gene expression of gluconeogensis and inflammatory cytokines was also down-regulated in the OA and PEE groups, suggesting that administration of OA or PEE could ameliorate obesity-induced insulin resistance, as well as prevent hyperlipidemia.

Oleanolic Acid and Ursolic Acid in Commercial Dried Fruits

“…3). This corresponds to previous findings that have shown that the presence of OA in raisins is independent of whether the grapevine cultivar is red or white (Orbán et al, 2009;Yunoki et al, 2008). We were unable to confirm the reasons for the differences in OA content between the different raisin types in this study, as the OA content in the raw materials and any changes that occurred during manufacture were unknown.…”

Antioxidant comparative effects of two grape pomace Mexican extracts from vineyards on erythrocytes

“…Methanol extract yields obtained by the maceration and Soxhlet methods were 7% and 8.2%, respectively (g/100 g of dry weight). Extraction yields from white and red grape pomace have been reported in the range of 7-37% (Yunoki et al, 2008). The quality of grape pomace extract is due to both its yield and its phenolic content.…”

Muscadine Grape (Vitis rotundifolia) and Wine Phytochemicals Prevented Obesity-Associated Metabolic Complications in C57BL/6J Mice

“…Similar observations were made in mice fed resveratrol (0.4%) for 15 weeks, 25 grape seed extract (250 mg/kg bw) for 12 weeks, 5 and dietary wine pomace extract (0.45%) for 4 weeks. 17 Feeding mice with HF diet increased the weight of epididymal adipose tissue by 67% compared to the fat mass in their lean counterparts on LF diets (Table 3). Supplementation of MGP and MWP in the HF diet significantly reduced fat mass by 29 and 12.5%, respectively, as compared to the HF group.…”