PPARdelta activation inhibits angiotensin II induced cardiomyocyte hypertrophy by suppressing intracellular Ca2+ signaling pathway.

Abstract

Peroxisome proliferator-activated receptors delta (PPARdelta) is known to be expressed ubiquitously, and the predominant PPAR subtype of cardiac cells. However, relatively less is known regarding the role of PPARdelta in cardiac cells except that PPARdelta ligand treatment protects cardiac hypertrophy by inhibiting NF-kappaB activation. Thus, in the present study, we examined the effect of selective PPARdelta ligand L-165041 on angiotensin II (AngII) induced cardiac hypertrophy and its underlying mechanism using cardiomyocyte. According to our data, L-165041 (10 microM) inhibited AngII-induced [(3)H] leucine incorporation, induction of the fetal gene atrial natriuretic factor (ANF) and increase of cardiomyocyte size. Previous studies have implicated the activation of focal adhesion kinase (FAK) in the progress of cardiomyocyte hypertrophy. L-165041 pretreatment significantly inhibited AngII-induced intracellular Ca(2+) increase and subsequent phosphorylation of FAK. Further experiment using Ca(2+) ionophore A23187 confirmed that Ca(2+) induced FAK phosphorylation, and this was also blocked by L-165041 pretreatment. In addition, overexpression of PPARdelta using adenovirus significantly inhibited AngII-induced intracellular Ca(2+) increase and FAK expression, while PPARdelta siRNA treatment abolished the effect of L-165041. These data indicate that PPARdelta ligand L-165041 inhibits AngII induced cardiac hypertrophy by suppressing intracellular Ca(2+)/FAK/ERK signaling pathway in a PPARdelta dependent mechanism.

• Authors: Kuy-Sook Lee, Jin-Hee Park, Seahyoung Lee, Hyun-Joung Lim, Hyun-Young Park
• Journal: Journal of cellular biochemistry (J Cell Biochem) Vol. 106 Issue 5 Pg. 823-34 (Apr 01 2009) ISSN: 1097-4644 [Electronic] United States
• PMID: 19224536 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• PPAR delta
• Angiotensin II
• Focal Adhesion Protein-Tyrosine Kinases
• Extracellular Signal-Regulated MAP Kinases
• Calcium

Topics

• Angiotensin II (pharmacology)
• Animals
• Calcium (metabolism)
• Extracellular Signal-Regulated MAP Kinases
• Focal Adhesion Protein-Tyrosine Kinases (genetics)
• Hypertrophy
• Myocytes, Cardiac (pathology)
• PPAR delta (genetics, metabolism)
• Rats
• Signal Transduction