Short-term Administration of Conjugated Linoleic Acid Reduces Liver Triglyceride Concentration and Phosphatidate Phosphohydrolase Activity in OLETF Rats

  • Rahman, Shaikh Mizanoor (Department of Applied Biological Sciences, Saga University) ;
  • Huda, M. Nazmul (Department of Biochemistry and Molecular Biology, University of Dhaka) ;
  • Uddin, M. Nas (Department of Biochemistry and Molecular Biology, University of Dhaka) ;
  • Akhteruzzaman, Sharif (Department of Biochemistry and Molecular Biology, University of Dhaka)
  • Published : 2002.09.30


The present study explored the short-term effects of dietary conjugated-linoleic acid (CLA) on liver lipid metabolism in starved/refed Otsuka Long Evans Tokushima Fatty (OLETF) rats. Male OLETF rats (12 weeks old) were starved for 24 hours, then refed for 48 hours with either a CLA diet [7.5% CLA and 7.5% Safflower oil (SAF)] or a SAF control diet (15% SAF). The results demonstrated a 30% reduction of hepatic triglyceride (TG) concentration in the CLA group when compared to the control group. Liver cholesterol concentration was also 26% lower in the CLA fed rats. The activity of mitochondrial carnitine palmitoyltransferase, the rate-limiting enzyme of fatty acid oxidation, was moderately elevated by 1.2-fold in the livers of the CLA group when compared to the control. In contrast, phosphatidate phosphohydrolase, the rate-limiting enzyme for TG synthesis, was found to be 20% lower in the livers of the CLA-fed rats. Therefore, dietary CLA evidently lowers liver lipid concentrations through a reduced TG synthesis and enhanced fatty acid oxidation in starved/refed OLETF rats.



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