Reactive oxygen species (ROS) mediate apoptosis in many different cell types. We have previously shown that the antioxidant Mn(III) tetrakis(5,10,15,20-benzoic acid)porphyrin (MnTBAP) decreased intracellular ROS and prevented the apoptosis of activated T cells in vitro. To determine the mechanism(s) by which MnTBAP afforded such protection, we used Affymetrix (Santa Clara, CA) gene arrays to co...

Long-term potentiation (LTP) in hippocampal area CA1 is generally dependent on N-methyl--aspartate (NMDA) receptor activation. Reactive oxygen species (ROS), including superoxide, are produced in response to NMDA receptor activation in a number of brain regions, including the hipppocampus. In this study, two cell-permeable manganese porphyrin compounds that mimic superoxide dismutase (SOD) were...

Oxidative damage to mitochondrial DNA (mtDNA) has been linked to the pathogenicity of diabetic nephropathy. We tested the hypothesis that mtDNA copy number may be increased in human mesangial cells in response to high glucose-induced reactive oxygen species (ROS) to compensate for damaged mtDNA. The effect of manganese superoxide dismutase mimetic (MnTBAP) on glucose-induced mtDNA copy number w...

COX-2/mPGES-1/PGE2 cascade is of importance in the pathogenesis of kidney injury. Meanwhile, recent studies documented a detrimental role of mitochondrial oxidative stress in kidney diseases. The present study was undertaken to investigate the role of mitochondrial oxidative stress in albumin-induced activation of COX-2/mPGES-1/PGE2 cascade in renal proximal tubular cells. Following albumin ove...

PURPOSE Oxidative stress is related to the carcinogenic pathway of reflux esophagitis to Barrett's metaplasia to esophageal adenocarcinoma (EAC). Recent studies have shown that a decreased manganese superoxide dismutase (MnSOD) level is associated with the increased incidences of Barrett's esophagus (BE) and EAC. The aim of this study was to investigate MnSOD supplementation as a chemopreventiv...

Background: This study was carried out to evaluate the pattern of reactive oxygen species (ROS) variations during in vitro oocyte maturation and embryo development in sheep, and to investigate whether embryo culture condition and the presence of cell-permeable superoxide dismutase mimetic [Manganese (III) meso-tetrakis (4-benzoic acid) porphyrin (MnTBAP)] can influence ROS pattern. Materials an...

Generation of reactive oxygen intermediates (ROI) following antigen receptor ligation is critical to promote cellular responses. However, the effect of antioxidant treatment on humoral immunity during a viral infection was unknown. Mice were infected with lymphocytic choriomeningitis virus (LCMV) and treated with Mn(III)tetrakis(4-benzoic acid)porphyrin chloride (MnTBAP), a superoxide dismutase...

Reactive oxygen species (ROS) are believed to be involved in triggering cardiac ischemic preconditioning (IPC). Decreased formation of ROS on reperfusion after prolonged ischemia may in part underlie protection by IPC. In heart models, these contentions have been based either on the effect of ROS scavengers to abrogate IPC-induced preservation or on a measurement of oxidation products on reperf...

UNLABELLED Reactive oxygen species (ROS) are largely responsible for cardiac injury consequent to ischemia and reperfusion, but, paradoxically, there is evidence suggesting that anesthetics induce preconditioning (APC) by generating ROS. We hypothesized that sevoflurane generates the ROS superoxide (O(2)(.-)), that APC attenuates O(2)(.-) formation during ischemia, and that this attenuation is ...

Adaptive mechanisms involving upregulation of cytoprotective genes under the control of transcription factors such as Nrf2 exist to protect cells from permanent damage and dysfunction under stress conditions. Here we explore of the hypothesis that Nrf2 activation by reactive oxygen and nitrogen species modulates cytotoxicity during hypoxia (H) with and without reoxygenation (H/R) in H9C2 cardio...