The role of eNOS, iNOS, and NF-kappaB in upregulation and activation of cyclooxygenase-2 and infarct size reduction by atorvastatin.
Pretreatment with atorvastatin (ATV) reduces infarct size (IS) and increases myocardial expression of phosphorylated endothelial nitric oxide synthase (p-eNOS), inducible NOS (iNOS), and cyclooxygenase-2 (COX2) in the rat. Inhibiting COX2 abolished the ATV-induced IS limitation without affecting p-eNOS and iNOS expression. We investigated 1) whether 3-day ATV pretreatment limits IS in eNOS(-/-) and iNOS(-/-) mice and 2) whether COX2 expression and/or activation by ATV is eNOS, iNOS, and/or NF-kappaB dependent. Male C57BL/6 wild-type (WT), University of North Carolina eNOS(-/-) and iNOS(-/-) mice received ATV (10 mg.kg(-1).day(-1); ATV(+)) or water alone (ATV(-)) for 3 days. Mice underwent 30 min of coronary artery occlusion and 4 h of reperfusion, or hearts were harvested and subjected to ELISA, immunoblotting, biotin switch, and electrophoretic mobility shift assay. As a result, ATV reduced IS only in the WT mice. ATV increased eNOS, p-eNOS, iNOS, and COX2 levels and activated NF-kappaB in WT mice. It also increased myocardial COX2 activity. In eNOS(-/-) mice, ATV increased COX2 expression but not COX2 activity or iNOS expression. NF-kappaB was not activated by ATV in the eNOS(-/-) mice. In the iNOS(-/-) mice, eNOS and p-eNOS levels were increased but not iNOS and COX2 levels; however, NF-kappaB was activated. In conclusion, both eNOS and iNOS are essential for the IS-limiting effect of ATV. The expression of COX2 by ATV is iNOS, but not eNOS or NF-kappaB, dependent. Activation of COX2 is dependent on iNOS.
Ye
Yumei
Y
Department of Internal Medicine, Univ. of Texas Medical Branch, Galveston, TX 77555-0553, USA.
Martinez
Juan D
JD
Perez-Polo
Regino J
RJ
Lin
Yu
Y
Uretsky
Barry F
BF
Birnbaum
Yochai
Y
D015121:6-Ketoprostaglandin F1 alpha / Q000378:metabolism; D000818:Animals; D000069059:Atorvastatin; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D004195:Disease Models, Animal; D024202:Electrophoretic Mobility Shift Assay; D004789:Enzyme Activation; D004797:Enzyme-Linked Immunosorbent Assay; D006538:Heptanoic Acids / Q000494:pharmacology*; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology*; D015151:Immunoblotting; D053612:Janus Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009203:Myocardial Infarction / Q000201:enzymology / Q000473:pathology / Q000517:prevention & control*; D009206:Myocardium / Q000201:enzymology* / Q000473:pathology; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism*; D052250:Nitric Oxide Synthase Type III; D010455:Peptides / Q000494:pharmacology; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011758:Pyrroles / Q000494:pharmacology*; D013997:Time Factors; D020032:Tyrphostins / Q000494:pharmacology; D015854:Up-Regulation
D006538:Heptanoic Acids; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D016328:NF-kappa B; D010455:Peptides; D047428:Protein Kinase Inhibitors; D011758:Pyrroles; C118258:SN50 peptide; D020032:Tyrphostins; C095512:alpha-cyano-(3,4-dihydroxy)-N-benzylcinnamide; D015121:6-Ketoprostaglandin F1 alpha; D000069059:Atorvastatin; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; C496317:Nos2 protein, mouse; C496315:Nos3 protein, mouse; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2; D053612:Janus Kinases