Effect of dietary wine pomace extract and oleanolic acid on plasma lipids in rats fed high-fat diet and its DNA microarray analysis.
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.
Yunoki
Keita
K
Department of Agricultural and Life Science, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan.
Sasaki
Gaku
G
Tokuji
Yoshihiko
Y
Kinoshita
Mikio
M
Naito
Akihiko
A
Aida
Kazuhiko
K
Ohnishi
Masao
M
D000818:Animals; D005223:Fats / Q000378:metabolism*; D015870:Gene Expression / Q000187:drug effects; D020869:Gene Expression Profiling; D006801:Humans; D008055:Lipids / Q000097:blood*; D008099:Liver / Q000378:metabolism; D008297:Male; D009765:Obesity / Q000178:diet therapy*; D009828:Oleanolic Acid / Q000032:analysis / Q000494:pharmacology*; D020411:Oligonucleotide Array Sequence Analysis; D009929:Organ Size; D010936:Plant Extracts / Q000032:analysis / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects; D027843:Vitis / Q000737:chemistry*
D005223:Fats; D008055:Lipids; D010936:Plant Extracts; D009828:Oleanolic Acid