There is now compelling evidence that the L-arginine/nitric oxide (NO) pathway generates the non-adrenergic non-cholinergic (NANC) neurotransmitter which mediates smooth muscle relaxation in a variety of nitrergically-innervated tissues. However, one strange aspect of this nitrergic neurotransmission process is that certain drugs (i.e. superoxide generators and NO-scavengers) powerfully inhibit...

Superoxide dismutase (SOD) is a very important reactive oxygen species (ROS)-scavenging enzyme. In this study, the functions of a Cu/Zn SOD gene (SaCu/Zn SOD), from Sedum alfredii, a cadmium (Cd)/zinc/lead co-hyperaccumulator of the Crassulaceae, was characterized. The expression of SaCu/Zn SOD was induced by Cd stress. Compared with wild-type (WT) plants, overexpression of SaCu/Zn SOD gene in ...

The dinuclear zinc complex Zn2L2 (HL=2-{[[di(2-pyridyl)methyl](methyl)amino]methyl}phenol) has been synthesized and isolated as colorless crystals. interaction of the compound with superoxide in anhydrous organic solvents evaluated by CV, stopped-flow Uv-vis, EPR ESI-MS suggesting binding activation coordinated superoxide, thanks to Lewis acidity Zn(II) centers. results obtained this study high...

To investigate the structural/functional role of the dimeric structure in Cu,Zn superoxide dismutases, we have studied the stability to a variety of agents of the Escherichia coli enzyme, the only monomeric variant of this class so far isolated. Differential scanning calorimetry of the native enzyme showed the presence of two well defined peaks identified as the metal free and holoprotein. Unli...

The endothelium plays an important role in maintaining vascular homeostasis by synthesizing and releasing several vasodilating factors, including prostacyclin, NO, and endothelium-derived hyperpolarizing factor (EDHF). We have recently identified that endothelium-derived H2O2 is an EDHF in mesenteric arteries of mice and humans and in porcine coronary microvessels. However, the mechanism for th...

Superoxide dismutases (EC 1.15.1.1) in vascular plants representing different evolutionary levels were characterized using polyacrylamide gel electrophoresis. The three forms of the enzyme were distinguished from each other based on the following criteria: a) the Cu-Zn enzyme is sensitive to cyanide wherease the Fe and Mn enzymes are not; and b) the Cu-Zn and Fe enzymes are inhibited by H(2)O(2...

Superoxide dismutase (SOD, EC 1.15.1.1) is an important metal-containing antioxidant enzyme that provides the first line of defense against toxic superoxide radicals by catalyzing their dismutation to oxygen and hydrogen peroxide. SOD is classified into four metalloprotein isoforms, namely, Cu/Zn SOD, Mn SOD, Ni SOD and Fe SOD. The structural models of soybean SOD isoforms have not yet been sol...

AIM To assess serum Cu/Zn SOD (Superoxide Dismutase) concentration in individuals with clinical depression. SUBJECTS AND METHODS Serum from 36 individuals diagnosed with clinical depression and 18 healthy controls were tested for Cu/Zn SOD serum concentration using ELISAs. RESULTS Serum Cu/Zn SOD levels of depressed individuals (both with and without secondary anxiety) were significantly hi...