Since conjugated linoleic acid (CLA) has structural and physiological characteristics similar to peroxisome proliferators, we hypothesized that CLA would activate peroxisome proliferator-activated receptor (PPAR). We compared the effects of dietary CLA (0.0, 0.5, 1.0 and 1.5% by weight) with a peroxisome proliferator (0.01% Wy-14,643) in female and male Sprague-Dawley (SD) rats. Dietary CLA had little effect on body weight, liver weight, and hepatic peroxisome proliferation, compared to male rats fed Wy-14,643 diet. Lipid content in livers from rats fed 1.5% CLA and Wy-14,643 diets was increased (P < 0.01) when compared to rats fed control diets regardless of gender. Hepatic acyl-CoA oxidase (ACO) mRNA levels were increased 3-fold in male rats fed 1.5% CLA diet compared to rats fed control diets while Wy- 14,643 supported ~30-fold ACO mRNA accumulation. A similar response was observed for liver fatty acid-binding protein (L-FABP) mRNA. The effect of dietary treatments on hepatic PPAR-responsive genes in female rats was weaker than in male rats. The (9Z, 11E)-CLA isomer activated PPARα in transfected cells to a similar extent as Wy-14,643, whereas the furan-CLA metabolite was comparable to bezafibrate on activating PPARβ. These data suggest that while CLA was able to activate PPARs it is not a peroxisome proliferator in SD rats.
|Original language||English (US)|
|Number of pages||12|
|Journal||Biochimica et Biophysica Acta - Molecular and Cell Biology of Lipids|
|State||Published - Jan 4 1999|
All Science Journal Classification (ASJC) codes
- Molecular Biology
- Cell Biology