We have previously shown that high-sugar diets increase mortality and left ventricular (LV) dysfunction during pressure overload. The mechanisms behind these diet-induced alterations are unclear but may involve increased oxidative stress in the myocardium. The present study examined whether high-fructose feeding increased myocardial oxidative damage and exacerbated systolic dysfunction after tr...

The present study evaluated whether reactive oxygen species-induced alterations in bioavailability of 20-HETE in the kidney contribute to the antihypertensive and renoprotective actions of antioxidant therapy with Tempol in the Dahl salt-sensitive (DS) rat. Superoxide inhibited the synthesis of 20-HETE by renal cortical microsomes and enhanced breakdown of 20-HETE to a more polar product. Addit...

OBJECTIVE We hypothesized that reactive oxygen species (ROS) contribute to progression of aortic valve (AV) calcification/stenosis. METHODS AND RESULTS We investigated ROS production and effects of antioxidants tempol and lipoic acid (LA) in calcification progression in rabbits given 0.5% cholesterol diet +10(4) IU/d Vit.D2 for 12 weeks. Superoxide and H2O2 microfluorotopography and 3-nitroty...

Fanconi anemia (FA) is a genetic disorder characterized by congenital abnormalities, bone marrow failure, and marked cancer susceptibility. FA patients have an elevated risk of developing hematologic malignancies and solid tumors. Using Fancd2(-/-) knockout mice as a model of FA, we examined the potential of tempol, a nitroxide antioxidant and a superoxide dismutase mimetic, as a tumor-delaying...

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the progressive dysfunction and death of motor neurons by mechanisms that remain unclear. Evidence indicates that oxidative mechanisms contribute to ALS pathology, but classical antioxidants have not performed well in clinical trials. Cyclic nitroxides are an alternative worth exploring because they are mu...

Recent studies have suggested that the enhanced release of reactive oxygen species (ROS) plays an important role in the pathogenesis of clinical inflammatory bowel disease (IBD), such as ulcerative colitis and Crohn's disease. In the present study, we investigated the effects of the free radical scavengers edaravone and tempol in the development of experimental dextran sulfate sodium (DSS)-indu...

Increased renal endothelin-1 (ET-1) production and an ETA receptor-dependent increase in glomerular albumin permeability (Palb) accompany type 1 diabetes mellitus (T1D). We hypothesized that T1D-induced oxidative stress contributes to renal ET-1 production and glomerular Palb Male rats with streptozotocin-induced T1D were provided free access to drinking water without additives (T1D rats) or co...

BACKGROUND Mitochondrial dysfunction is a crucial mechanism by which cisplatin, a potent chemotherapeutic agent, causes nephrotoxicity where mitochondrial electron transport complexes are shifted mostly toward imbalanced reactive oxygen species versus energy production. In the present study, the protective role of tempol, a membrane-permeable superoxide dismutase mimetic agent, was evaluated on...

A membrane-permeable SOD mimetic, 4-hydroxytetramethyl-piperidine-1-oxyl (tempol), has been used as an antioxidant to prevent hypertension. We recently found that this SOD mimetic could not prevent development of hypertension induced by inhibition of renal medullary SOD with diethyldithiocarbamic acid. The present study tested a hypothesis that increased H2O2 counteracts the effects of tempol o...

The effect of the chronic and acute antioxidant tempol (superoxide dismutase mimetic) treatment on cardiac ischemic tolerance was investigated in adult male Wistar rats. The first experimental group was given tempol (1 mM) in drinking water for three weeks, the second group received tempol (100 mg/kg, i.v.) 10 min before test ischemia, and control rats received the same volume of solvent. Anest...