Improved n-3 fatty acid status does not modulate insulin resistance in fa/fa Zucker rats

Prostaglandins Leukot Essent Fatty Acids. Nov-Dec 2009;81(5-6):331-9. doi: 10.1016/j.plefa.2009.09.008. Epub 2009 Oct 28.

Abstract

The objective was to examine the effect of polyunsaturated fatty acid type (plant vs fish oil-derived n-3, compared to n-6 fatty acids in the presence of constant proportions of saturated, monounsaturated and polyunsaturated fatty acids) on obesity, insulin resistance and tissue fatty acid composition in genetically obese rats. Six-week-old fa/fa and lean Zucker rats were fed with a 10% (w/w) mixed fat diet containing predominantly flax-seed, menhaden or safflower oils for 9 weeks. There was no effect of dietary lipid on obesity, oral glucose tolerance (except t=60min insulin), pancreatic function or molecular markers related to insulin, glucose and lipid metabolism, despite increased n-3 fatty acids in muscle and adipose tissue. The menhaden oil diet reduced fasting serum free fatty acids in both fa/fa and lean rats. These data suggest that n-3 composition does not alter obesity and insulin resistance in the fa/fa Zucker rat model when dietary lipid classes are balanced.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipose Tissue, White / drug effects
  • Adipose Tissue, White / pathology
  • Animal Feed / analysis
  • Animals
  • Body Fat Distribution
  • Body Weight / drug effects
  • Cell Size / drug effects
  • Dietary Fats / analysis
  • Dietary Fats / pharmacology
  • Fatty Acids, Omega-3 / blood*
  • Gene Expression Profiling
  • Glucose Tolerance Test
  • Health Status
  • Insulin Resistance / physiology*
  • Islets of Langerhans / drug effects
  • Islets of Langerhans / pathology
  • Lipid Metabolism / drug effects
  • Lipid Metabolism / genetics
  • Obesity / blood*
  • Obesity / metabolism
  • Obesity / pathology
  • Organ Size / drug effects
  • Rats
  • Rats, Zucker

Substances

  • Dietary Fats
  • Fatty Acids, Omega-3