NADPH oxidase is critically involved in increased blood pressure, vascular hypertrophy, inflammation and endothelial dysfunction in experimental and clinical hypertension. We hypothesized that NADPH oxidase might also play a role in the development of spontaneous aortic tone in spontaneously hypertensive rats (SHR). Wistar Kyoto rats (WKY) were used as normotensive controls. Tone was recorded u...

Rac-dependent NADPH oxidases generate reactive oxygen species used in cell signaling and microbial killing or both. Whereas the mechanisms leading to NADPH oxidase activation are fairly well studied, the mechanisms that control downregulation of this enzyme complex remain unclear. We hypothesized that reactive oxygen species produced by NADPH oxidase may autoregulate the complex by inhibiting R...

Superoxide produced by the phagocyte reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is essential for host defense. Enzyme activation requires translocation of p67(phox), p47(phox), and Rac-GTP to flavocytochrome b558 in phagocyte membranes. To examine the regulation of phagocytosis-induced superoxide production, flavocytochrome b558, p47(phox), p67(phox), and the FcgammaIIA...

Hypoglycemic coma and brain injury are potential complications of insulin therapy. Certain neurons in the hippocampus and cerebral cortex are uniquely vulnerable to hypoglycemic cell death, and oxidative stress is a key event in this cell death process. Here we show that hypoglycemia-induced oxidative stress and neuronal death are attributable primarily to the activation of neuronal NADPH oxida...

Oxidative stress has been linked to the origin and progression of cardiovascular diseases. Nicotinamide adenine dinucleotide phosphate, reduced form (NADPH) oxidase is a multi-component, NADPH-dependent enzyme that generates superoxide anion in the presence of molecular oxygen. The enzyme has been identified and characterized in all 3 vascular wall cell types and represents the major source of ...

Prodigiosins are natural red pigments that have multi-biological activities. Recently, we discovered a marine bacterial strain, which produces a red pigment. Extensive two-dimensional nuclear magnetic resonance and mass spectrometry analysis showed that the pigment is a prodigiosin analogue (PG-L-1). Here, we investigated the effect of PG-L-1 on NADPH oxidase activity in macrophage cells. PG-L-...

BACKGROUND Evidence exists that oxidative stress promotes the tyrosine phosphorylation of N-methyl-D-aspartate receptor (NMDAR) subunits during post-ischemic reperfusion of brain tissue. Increased tyrosine phosphorylation of NMDAR NR2A subunits has been reported to potentiate receptor function and exacerbate NMDAR-induced excitotoxicity. Though the effect of ischemia on tyrosine phosphorylation...

F ~hagocytic cells contain a complicated enzyme system, termed NADPH oxidase, that is responsible for the production of toxic oxygen species (1). The enzyme transfers electrons from NADPH to 02, forming O2-, which then can dismutate into H202. Subsequently, other oxygen derivatives, such as hydroxyl radical and hypochlorous acid, may be formed. Collectively, these oxygen products are toxic to c...

Renal oxidative stress and nitric oxide (NO) deficiency are key events in hypertension. Stimulation of a nitrate-nitrite-NO pathway with dietary nitrate reduces blood pressure, but the mechanisms or target organ are not clear. We investigated the hypothesis that inorganic nitrate and nitrite attenuate reactivity of renal microcirculation and blood pressure responses to angiotensin II (ANG II) b...