魚油在含膽固醇之飼料中提高倉鼠低密度脂蛋白膽固醇濃度卻不改變肝臓低密度脂蛋白受體mRNA之表現

Fish Oil in a Cholesterol Contatining Diet Elevates LDL-cholesterol without Changing LDL-receptor mRNA in Hamsters

彭郁玲(Yu-Ling Peng) ； 呂紹俊(Shao-Chun Lu) ； 黃伯超(Po-Chao Huang)

《中華民國營養學會雜誌》 23卷3期 (1998/08) Pp. 309-322

https://doi.org/10.6691/JCNS.199808_23(3).0008

摘要

This study was designed to investigate the effect of 0%, 1.5%, 3% or 4.5% fish oil diet on plasma lipids, liver lipids and liver LDL-receptor mRNA expression with or without supplementation of 0.1% dietary cholesterol. Forty Golden Syrian hamsters weighing about 50g were divided into 8 groups and were fed with one of the experimental diets for 4 weeks. In hamsters consuming diets without cholesterol supplementation, plasma total-triglyceride (TG), VLDL-TG, total-cholesterol (C) and LDL-C decreased gradually as fish oil increased in the diet; but liver triglyceride and cholesterol were not significantly changed by fish oil. While in 0.1% cholesterol dietary groups, only 4.5% fish oil group had significantly lower plasma total-TG and VLDLTG than the 0% fish oil group; however, 1.5%, 3% and 4.5% fish oil groups all had higher total-C and LDL-C than the 0% fish oil group. The elevation of LDL-C was especially remarkable, from 42.2±2.2 of the 0% fish oil diet to 108.5±18.4mg/dL of the 4.5% fish oil diet. Addition of 0.1% cholesterol in the diet resulted in significant increase of liver cholesterol and decrease of LDL-receptor mRNA. The accumulation of liver cholesterol was lowered by fish oil, but LDL-receptor mRNA in 4.5% fish oil group was similar to that in 0% fish oil group. These data suggest that the effects of fish oil on lipid metabolism can be changed by dietary cholesterol. Also the elevation of LDL-C by fish oil in cholesterol containing diet is not due to low expression of LDL-receptor mRNA. The mechanism behind these changes is still not clear and requires further investigation.

關鍵字

魚油 ； 膽固醇 ； 低密度脂蛋白 ； 低度脂蛋白受體mRNA ； 倉鼠

並列摘要

This study was designed to investigate the effect of 0%, 1.5%, 3% or 4.5% fish oil diet on plasma lipids, liver lipids and liver LDL-receptor mRNA expression with or without supplementation of 0.1% dietary cholesterol. Forty Golden Syrian hamsters weighing about 50g were divided into 8 groups and were fed with one of the experimental diets for 4 weeks. In hamsters consuming diets without cholesterol supplementation, plasma total-triglyceride (TG), VLDL-TG, total-cholesterol (C) and LDL-C decreased gradually as fish oil increased in the diet; but liver triglyceride and cholesterol were not significantly changed by fish oil. While in 0.1% cholesterol dietary groups, only 4.5% fish oil group had significantly lower plasma total-TG and VLDLTG than the 0% fish oil group; however, 1.5%, 3% and 4.5% fish oil groups all had higher total-C and LDL-C than the 0% fish oil group. The elevation of LDL-C was especially remarkable, from 42.2±2.2 of the 0% fish oil diet to 108.5±18.4mg/dL of the 4.5% fish oil diet. Addition of 0.1% cholesterol in the diet resulted in significant increase of liver cholesterol and decrease of LDL-receptor mRNA. The accumulation of liver cholesterol was lowered by fish oil, but LDL-receptor mRNA in 4.5% fish oil group was similar to that in 0% fish oil group. These data suggest that the effects of fish oil on lipid metabolism can be changed by dietary cholesterol. Also the elevation of LDL-C by fish oil in cholesterol containing diet is not due to low expression of LDL-receptor mRNA. The mechanism behind these changes is still not clear and requires further investigation.

並列關鍵字

Fish oil ； cholesterol ； LDL ； LDL-receptor mRNA ； hamsters