多不饱和脂肪酸与单不饱和脂肪酸对饱和脂肪酸的比例对大鼠血浆和肝脏脂质浓度的影响。

Effects of the ratio of polyunsaturated and monounsaturated fatty acid to saturated fatty acid on rat plasma and liver lipid concentrations.

作者信息

Chang N W, Huang P C

机构信息

Department of Biochemistry, China Medical College, Taichung, Taiwan, Republic of China.

出版信息

Lipids. 1998 May;33(5):481-7. doi: 10.1007/s11745-998-0231-9.

DOI:10.1007/s11745-998-0231-9

PMID:9625595

Abstract

The effects of dietary monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid + MUFA/saturated fatty acid (PUFA + MUFA/SFA) ratio on plasma and liver lipid concentrations were studied. In experiment I, when rats were fed with 40% fat (energy%, PUFA/SFA ratio 1.0) and 1% (w/w) cholesterol (C) diets for 21 d, a large amount of MUFA (28.1 energy%, PUFA + MUFA/SFA = 5.7) in the diet was found to increase the plasma total C, triacylglycerol (TAG), and phospholipid (PL) as compared with the low-MUFA diet (7.0 energy%, PUFA + MUFA/SFA = 1.4). The plasma very low density lipoprotein (VLDL)-C, VLDL-TAG, VLDL-PL, and low density lipoprotein (LDL)-C increased significantly in the high-MUFA diet group, but high density lipoprotein (HDL)-C did not change significantly. The high-MUFA diet resulted in greater accumulation of liver C but lesser accumulation of TAG. In experiment II, when dietary SFA was fixed at a certain level (13.2 energy%; PUFA + MUFA/SFA = 2.0), rats given a larger amount of MUFA (23.1 energy%; PUFA/MUFA = 0.2; MUFA/SFA = 1.8) showed higher plasma and liver C levels than did the low-MUFA diet (7.7 energy%; PUFA/MUFA = 2.5; MUFA/SFA = 0.6). When PUFA was fixed at a certain level (24.4 energy%), there was not a significant difference in the plasma C level between the high- and low-MUFA dietary groups (PUFA + MUFA/SFA = 4.8 and 8.4), but the higher PUFA + MUFA/SFA diet, which was high in MUFA/SFA ratio, significantly decreased the plasma HDL-C and TAG levels. However, when MUFA content was fixed at a certain level (16.4 energy%), no significant difference was observed between the two groups with different PUFA/SFA ratios of 0.2 and 4.1, but liver C level was raised in the higher PUFA/SFA diet. It appears that the PUFA/SFA ratio alone is unsuitable to predict the change of plasma C level, because a large amount of dietary MUFA may lead to an increase of plasma and liver lipids in rats. It seems that the prerequisites for keeping low plasma and liver C are (i) low MUFA/SFA ratio, (ii) high PUFA/MUFA ratio, and (iii) PUFA + MUFA/SFA ratio not to exceed 2.

摘要

研究了膳食单不饱和脂肪酸（MUFA）以及多不饱和脂肪酸+MUFA/饱和脂肪酸（PUFA+MUFA/SFA）比值对血浆和肝脏脂质浓度的影响。在实验I中，当给大鼠喂食含40%脂肪（能量百分比，PUFA/SFA比值为1.0）和1%（w/w）胆固醇（C）的日粮21天时，发现日粮中大量的MUFA（28.1能量%，PUFA+MUFA/SFA=5.7）与低MUFA日粮（7.0能量%，PUFA+MUFA/SFA=1.4）相比，会增加血浆总胆固醇（C）、三酰甘油（TAG）和磷脂（PL）。高MUFA日粮组的血浆极低密度脂蛋白（VLDL）-C、VLDL-TAG、VLDL-PL和低密度脂蛋白（LDL）-C显著增加，但高密度脂蛋白（HDL）-C没有显著变化。高MUFA日粮导致肝脏胆固醇积累更多，但TAG积累较少。在实验II中，当膳食饱和脂肪酸（SFA）固定在一定水平（13.2能量%；PUFA+MUFA/SFA=2.0）时，给予较多MUFA（23.1能量%；PUFA/MUFA=0.2；MUFA/SFA=1.8）的大鼠血浆和肝脏胆固醇水平高于低MUFA日粮组（7.7能量%；PUFA/MUFA=2.5；MUFA/SFA=0.6）。当多不饱和脂肪酸（PUFA）固定在一定水平（24.4能量%）时，高、低MUFA日粮组之间的血浆胆固醇水平没有显著差异（PUFA+MUFA/SFA=4.8和8.4），但MUFA/SFA比值较高的高PUFA+MUFA/SFA日粮显著降低了血浆HDL-C和TAG水平。然而，当MUFA含量固定在一定水平（16.4能量%）时，PUFA/SFA比值分别为0.2和4.1的两组之间未观察到显著差异，但较高PUFA/SFA日粮组的肝脏胆固醇水平升高。似乎仅PUFA/SFA比值不足以预测血浆胆固醇水平的变化，因为大量的膳食MUFA可能导致大鼠血浆和肝脏脂质增加。看来保持低血浆和肝脏胆固醇的前提条件是：（i）低MUFA/SFA比值；（ii）高PUFA/MUFA比值；（iii）PUFA+MUFA/SFA比值不超过2。