Theodore A. Christopher

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BACKGROUND Recent evidence from cultured endothelial cell studies suggests that phosphorylation of endothelial nitric oxide synthase (eNOS) through the PI3-kinase-Akt pathway increases NO production. This study was designed to elucidate the signaling pathway involved in the antiapoptotic effect of insulin in vivo and to test the hypothesis that(More)
BACKGROUND Activation of p38 mitogen-activated protein kinase (MAPK) plays an important role in apoptotic cell death. The role of p38 MAPK in myocardial injury caused by ischemia/reperfusion, an extreme stress to the heart, is unknown. METHODS AND RESULTS Studies were performed with isolated, Langendorff-perfused rabbit hearts. Ischemia alone caused a(More)
BACKGROUND In vitro evidence suggests that the p38 mitogen-activated protein kinase (p38 MAPK) plays a crucial role in PMN activation and inflammatory cytokine production. However, the effect of p38 MAPK on myocardial reperfusion injury, a pathologic condition involving a typical inflammatory response, has not been fully examined. In the present study, we(More)
Objectives: Our previous study has shown that slow or “controlled” reperfusion for the ischemic heart reduces cardiomyocyte injury and myocardial infarction, while the mechanisms involved are largely unclear. In this study, we tested the hypothesis that enhancement of survival and prevention of apoptosis in hypoxic/reoxygenated cardiomyocytes by hypoxic(More)
BACKGROUND Omi/HtrA2 is a proapoptotic mitochondrial serine protease involved in caspase-dependent as well as caspase-independent cell death. However, the role of Omi/HtrA2 in the apoptotic cell death that occurs in vivo under pathological conditions remains unknown. The present study was designed to investigate whether Omi/HtrA2 plays an important role in(More)
BACKGROUND Several clinical studies have demonstrated that levels of adiponectin are significantly reduced in patients with type 2 diabetes and that adiponectin levels are inversely related to the risk of myocardial ischemia. The present study was designed to determine the mechanism by which adiponectin exerts its protective effects against myocardial(More)
Oxygen-derived free radicals play a critical role in atherogenesis and reperfusion injury. The present experiment evaluated the effects of carvedilol, a new beta adrenoreceptor blocker with potent free radical-scavenging activity, on myocardial ischemia and reperfusion injury in a hypercholesterolemic rabbit model. New Zealand rabbits were fed a normal(More)
The present experiment determined the effects of glutathione and ascorbic acid, the two most important hydrophilic antioxidants, on myocardial ischemia-reperfusion injury and evaluated their relative therapeutic values. Isolated rat hearts were subjected to ischemia (30 min) and reperfusion (120 min) and treated with ascorbic acid, glutathione monoethyl(More)
OBJECTIVE Reduced plasma adiponectin (APN) in diabetic patients is associated with endothelial dysfunction. However, APN knockout animals manifest modest systemic dysfunction unless metabolically challenged. The protein family CTRPs (C1q/TNF-related proteins) has recently been identified as APN paralogs and some CTRP members share APN's metabolic regulatory(More)
BACKGROUND Intracellular proteins involved in oxidative stress and apoptosis are nitrated in diseased tissues but not in normal tissues; definitive evidence to support a causative link between a specific protein that is nitratively modified with tissue injury in a specific disease is limited, however. The aims of the present study were to determine whether(More)