Masou salmon (Oncorhynchus masou) ethanol extract decreases 3-hydroxy-3-methylglutaryl coenzyme A reductase expression in diet-induced obese mice.
This study was designed to evaluate the hypocholesterolemic effects of masou salmon 70% ethanol extract (MSE) and to determine the molecular mechanism by which MSE exerts its effects in high-fat (HF) diet-induced obese mice. We hypothesize that the MSE may contain abundant n-3 fatty acids, so a diet containing MSE may also have hypolipidemic effects by assessing several key gene expressions in cholesterol metabolism such as the low-density lipoprotein (LDL) receptor, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, and cholesterol 7alpha-hydroxylase (CYP7A1). To test this hypothesis, C57BL/6J mice were fed a 40% HF diet for 5 weeks, after which time the animals were fed an HF diet containing 0 mg/kg, 75 mg/kg, or 150 mg/kg MSE (HF, HF + MSE 1, and HF + MSE 2 groups, respectively) for an additional 4 weeks (n = 8 in each group, for a total of 24 mice). We found that feeding MSE with an HF diet prevented hypercholesterolemia in diet-induced obese mice; daily MSE feeding reduced total cholesterol levels in plasma and liver by 12.3% and 16.2%, respectively. Furthermore, we examined the expression of key cholesterol metabolism genes by reverse transcription-polymerase chain reaction and found that messenger RNA levels of HMG-CoA reductase were decreased by up to 5-fold, but the expression of both LDL receptor and CYP7A1 did not change. Thus, MSE may exert its hypocholesterolemic effect by altering the expression of HMG-CoA reductase.
Oh
Hyun-Taek
HT
Department of Food Science and Biotechnology, Division of Biotechnology, School of Bioscience and Biotechnology, Kangwon National University, Chuncheon 200-701, South Korea.
Chung
Mi Ja
MJ
Kim
Soo-Hyun
SH
Choi
Hyun-Jin
HJ
Ham
Seung-Shi
SS
D000818:Animals; D000924:Anticholesteremic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001786:Blood Glucose; D001835:Body Weight / Q000187:drug effects; D002784:Cholesterol / Q000378:metabolism*; D002790:Cholesterol 7-alpha-Hydroxylase / Q000378:metabolism; D008076:Cholesterol, HDL / Q000378:metabolism; D004032:Diet; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology / Q000627:therapeutic use*; D006903:Hydroxymethylglutaryl CoA Reductases / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008820:Mice, Obese; D009765:Obesity / Q000178:diet therapy*; D017683:Oncorhynchus; D012333:RNA, Messenger / Q000378:metabolism; D011973:Receptors, LDL / Q000378:metabolism; D014280:Triglycerides / Q000378:metabolism
D000924:Anticholesteremic Agents; D001786:Blood Glucose; D008076:Cholesterol, HDL; D015525:Fatty Acids, Omega-3; D012333:RNA, Messenger; D011973:Receptors, LDL; D014280:Triglycerides; D002784:Cholesterol; D006903:Hydroxymethylglutaryl CoA Reductases; D002790:Cholesterol 7-alpha-Hydroxylase; C502772:Cyp7a1 protein, mouse