Abstract
In the present study, we hypothesized that onion peel extract (OPE) alters hepatic gene expression to improve blood cholesterol profiles. To investigate the effect of OPE to test our hypothesis, Sprague-Dawley rats were fed ad libitum for 8 weeks with the control, high-fat diet (HFD) or the high-fat diet with 0.2% OPE supplementations (HFD + OPE). Messenger RNA (mRNA) levels of genes in cholesterol metabolism and fatty acid metabolism were examined by semiquantitative reverse transcriptase polymerase chain reaction. The OPE in HFD reverted high fat-induced reduction in mRNA levels of sterol regulatory element-binding protein-2, low-density lipoprotein receptor, and hydroxyl-3-methylglutaryl coenzyme reductase genes in the liver comparable with the levels of the control group. Onion peel extract slightly increased stearoyl-coA desaturase 1 (SCD-1) expression compared with high-fat feeding. However, sterol regulatory element-binding protein-1c and fatty acid synthase were not affected by high-fat or OPE feeding. Onion peel extract also enhanced expression of ATP-binding cassette transporter A1, peroxisome proliferator-activated receptor γ2 and scavenger receptor class B type I genes when compared with high-fat feeding. However, OPE did not influence high fat-triggered changes in apolipoprotein A1 mRNA levels and liver X receptor α were not affected by either high-fat or OPE feeding. Our results suggest that OPE changes the expression of genes associated with cholesterol metabolism in favor of lowering blood low-density lipoprotein cholesterol and enhancing high-density lipoprotein cholesterol through increasing mRNA abundance of low-density lipoprotein receptor and ATP-binding cassette transporter A1 genes.
Original language | English |
---|---|
Pages (from-to) | 210-217 |
Number of pages | 8 |
Journal | Nutrition Research |
Volume | 32 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2012 Mar |
Bibliographical note
Funding Information:This work was supported by the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (2011-0004530).
Keywords
- ABCA1, LXRα
- HMG-CoA reductase
- LDL receptor
- Onion peel extract
- SREBP-2
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism
- Endocrinology
- Nutrition and Dietetics