Abstract
Angiotensin II (ANG II), a product of renin-angiotensin system activation, enhances collagen synthesis, which is a key event in cardiac remodeling after myocardial infarction. Inhibition of cardiac remodeling is now a target of multiple therapies, including 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, commonly known as statins, and peroxisome proliferator-activated receptor-gamma (PPAR-gamma) ligands. We examined the potential antifibrotic effect of the combination of a statin (pravastatin) and a PPAR-gamma ligand (pioglitazone) in ANG II-treated mouse cardiac fibroblasts. ANG II treatment induced procollagen-1 expression, which was inhibited by pravastatin and pioglitazone in a dose-dependent fashion. Pretreatment of fibroblasts with low therapeutic concentrations of either pravastatin (0.1 microM) or pioglitazone (5 microM) only slightly decreased ANG II-induced NADPH oxidase expression, superoxide anion production, and procollagen-1 expression; however, the combination of pravastatin and pioglitazone markedly modulated these effects of ANG II. The combination also blocked ANG II-mediated p38 MAPK and p44/42 MAPK activation. Electrophoretic mobility shift assay showed that ANG II activated transcription factors NF-kappaB and activator protein-1 (AP-1). Although pravastatin and pioglitazone alone had a variable effect on NF-kappaB and AP-1 activation, their combination exerted a potent inhibitory effect on the activation of both NF-kappaB and AP-1. The effects of pravastatin and pioglitazone in combination on superoxide generation and procollagen-1 expression mimicked those of alpha-tocopherol and gamma-tocopherol, two potent antioxidants. Thus it appears that there is a positive interaction between pravastatin and pioglitazone in modulating ANG II-mediated oxidative stress, inhibiting MAPK activation, and procollagen-1 expression.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: American Journal of Physiology-Heart and Circulatory Physiology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.