Effects of Conjugated Linoleic Acid Supplement on the Composition of Fatty Acids, Expressions of delta-5 Desaturase (D5D) and Fatty Acid Desaturase2 (FADS2) Genes in Mice

식이지방에 첨가한 Conjugated Linoleic Acid가 지방산 조성, delta-5 Desaturase(D5D)와 Fatty Acid Desaturase2(FADS2) 유전자 발현에 미치는 영향

  • Hwang, Yun-Hee (Department of Food and Nutrition, College of Natural Science, Duksung Women's University) ;
  • Kang, Keum-Jee (Department of Food and Nutrition, College of Natural Science, Duksung Women's University)
  • 황윤희 (덕성여자대학교 식품영양학과) ;
  • 강금지 (덕성여자대학교 식품영양학과)
  • Published : 2007.10.30


We investigated the effects of conjugated linoleic acid (CLA) on the fatty acid composition in the plasma and liver, and the expressions of delta-5 desaturase (D5D) and fatty acid desaturase2 (FADS2) genes in ICR male mice using two different sources of fats in the diets. The experimental groups were divided into four groups: beef tallow (BT) and fish oil (FO), BT with CLA supplementation (BTC), and FO with CLA supplementation (FOC) groups. Ten mice in each group were fed with the experimental diets for 4 weeks. All mice were fed experimental diets containing 12% of total dietary fat (w/w) either with or without 0.5% CLA (w/w). Fatty acid compositions were analyzed in the plasma and liver using gas chromatography. The levels of D5D and FADS2 expression were analyzed by RT-PCR in the liver The results showed that CLA participates competitively with C18:2 in the elongation and desaturation processes, leading to significant increase in the levels of C20:4 and C22:6 in BTC group (p<0.05). The expression levels of D5D and FADS2 were higher in BT and BTC group than those of FO and FOC group. In particular, the expression of D5D gene was greatly upregulated in BTC group. Furthermore, the conversion ratios from C18:2 to C20:4 in the liver were higher in BTC group than those in other groups. Thus our results suggest that increased expressions of DSD and FADS2 genes may be responsible for the enhanced CLA effects on the desaturation in the BT containing saturated fatty acids rather than the FO rich in n-3 PUFA.


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