Dietary n-3 polyunsaturated fatty acids decrease hepatic triglycerides in Fischer 344 rats

Authors

  • James R. Levy,

    Corresponding author
    1. Section of Endocrinology and Metabolism, McGuire Veterans Administration Medical Center, Medical College of Virginia/Virginia Commonwealth University, Richmond, VA
    2. Division of Endocrinology and Metabolism, Medical College of Virginia/Virginia Commonwealth University, Richmond, VA
    • McGuire Veterans Administration Medical Center 111-P, 1201 Broad Rock Blvd., Richmond, VA 23249
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    • fax: 804-675-5425

  • John N. Clore,

    1. Division of Endocrinology and Metabolism, Medical College of Virginia/Virginia Commonwealth University, Richmond, VA
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  • Wayne Stevens

    1. Section of Endocrinology and Metabolism, McGuire Veterans Administration Medical Center, Medical College of Virginia/Virginia Commonwealth University, Richmond, VA
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Abstract

Dietary fatty acid composition modifies hepatic lipid metabolism. To determine the effects of fatty acids on hepatic triglyceride storage, rats were fed diets enriched in carbohydrates (control), fish oil, or lard. After 4 weeks, the animals were fasted overnight. In the morning, the animals were either sacrificed or fed 8 g of their respective diets before sacrifice. Animals ingested more food calories with diets containing fish oil than with other diets. However, fish oil–fed animals weighed less and had less body fat. In fish oil–fed animals, liver triglyceride was lower by 27% (P < .05) and 73% (P < .01) than in control- and lard-fed animals, respectively. Fish oil altered the postprandial gene expression of hepatic regulators of fatty acid degradation and synthesis. Fish oil feeding blunted the normal postprandial decline in fatty acid degradation genes (PPARα, CPT1, and ACO) and blunted the normal postprandial rise in triglyceride synthesis genes (SREBP1-c, FAS, SCD-1). Therefore, the direct postprandial effect of fish oil ingestion decreases the propensity for hepatic triglyceride storage. In conclusion, n-3 polyunsaturated fatty acids decrease total body weight, total body fat, and hepatic steatosis. (HEPATOLOGY 2004;39:608–616.)

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