MINIREVIEW

PPAR-Alpha and Insulin Sensitivity

M.M. HALUZÍK^{1, 2}, M. HALUZÍK<sup>1

1</sup>Third Department of Medicine, First Faculty of Medicine, Charles University and University Hospital, Prague and ²Department of Chemistry, Faculty of Science, University of Ostrava, Ostrava, Czech Republic

Received December 20, 2004
Accepted May 4, 2005
On-line available May 24, 2005

Summary
Peroxisome proliferator-activated receptors (PPAR) belong to the nuclear receptor superfamily of ligand-activated transcription factors. PPAR-α, first of its three subtypes (α, β, γ) has traditionally been considered an important regulator of lipid metabolism while its role in the regulation of insulin sensitivity has not been recognized until recently. Here we summarize the experimental and clinical studies focusing on the role of PPAR-α in the regulation of insulin sensitivity. In most of the experimental studies the activation of PPAR-α in rodents leads to improvement of insulin sensitivity by multiple mechanisms including improvement of insulin signaling due to a decrease of ectopic lipids in non-adipose tissues and decrease of circulating fatty acids and triglycerides. In contrast, the effect of PPAR-α agonist in humans is much less pronounced probably due to a lower expression of PPAR-α relative to rodents and possibly other mechanisms. Further clinical studies using more potent PPAR-α agonists on a larger population need to be performed to evaluate the possible role of PPAR-α in the regulation of insulin sensitivity in humans.


Key words
Peroxisome proliferator-activated receptor-alpha • Insulin sensitivity • Obesity• Adipose tissue