Influence of Dietary n3 Polyunsaturated Fatty Acids on Plasma Lipid-Lowering Effect and Peroxidation Level In Rats

쥐에서 n3계 불포화지방산 식이의 혈장지질 저하효과와 과산화물형성에 미치는 영향

  • Choi, Joo Sun (Department of Foods and Nutrition, Kyung Hee University)
  • Published : 1990.11.01

Abstract

To compare the hypolipidemic effect of n6 linoleic acid n3 $\alpha$-linolenic acid and n3 eicosapentaenoic acid plus docosahexaenoic acid, male Sprague Dawley rats weighing about 450g were fed the experimental diets for 6 weeks which composed of fat at 15%(W/W) level and were different only in dietary PUFA. Dietary fat was corn oil, perilla oil, and fish oil concentrate as a source of n6 linoleic acid, n3 $\alpha$-linolenic acid, and n3 eicosapentaenoic acid+docosahexaenoic acid, respectively. Plasma total Chol and HDL-chol levels were significantly-lower in fish oil group than in corn oil and erilla oil groups. Plasma cholesterol lowering effect of PUFa was in the order of n3 EPA+DHA>n3 $\alpha$-linolenic acid>n6 linoleic acid. Plasma TG was significantly lower in both fish oil and perilla oil groups than in corn oil group. Plasma TG-lowering effect was greater by n3 PUFA (EPA+DHA, $\alpha$-linolenic acid) than by n6 PUFA(linoleic acid). However, there were no significant effects on lipoprotein pattern hemolysis, and the levels of tocopherol and malondialdehyde in plasma and RBC by difference dietary fat with sufficient tocopherol supplement. Liver superoxide dismutase activity was significantly increased in proportion to the degree of fat unsaturation, thereby resulted in the lower level of MDA in fish oil group. In conclusion, fish oil and perilla oil rich in n3 PUFA may have important nutritional applications in the prevention and treatment of atherosclerotic disease.

Sprague Dawley 종 수컷쥐(체중 약 450kg) 48마리를 3군으로 나누어 종류가 다른 불포화지방산으로 구성된 실험식이를 6주간 투여하였다. 이때 지방을 15%(W/W)로, 불포화지방산인 n6 linoleic acid의 급원으로는 옥수수기름, n3 $\alpha$-linolenic acid의 급원으로는 들기름, n3 EPA와 DHA의 급원으로는 생선유를 투여하되, 포화지방산과 monoenoic acid의 총량을 거의 같게 공급하여 불포화지방산의 영향만을 관찰할 수 있도록 하였다. 어유를 투여한 군의 cholesterol과 HDL-chol양은 옥수수기름과 들기름을 투여한 군에 비해 유의성있게 낮았으며, 불포화지방산의 혈장 cholesterol을 저하시키는 능력은 n3 EPA+n3계 불포화지방산군인 어유와 들기름군이 n6계 불포화지방산군인 옥수수기름군에 비해 유의성있게 더 컸다. Lipoprotein의 상대적인 함량은 식이 불포화지방산의 종류에 의해 영향을 받지 않았으며, 혈장과 적혈구 및 간의 토로페롤 수준은 유사한 수준이었으며 과산화산물 활성은 지방산의 불포화도 정도에 비례하여 증가되었으며 SOD활성의 증가로 인해 간조직의 과산화물의 수준이 감소되었다.

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