Hemoglobin-based oxygen carriers (HBOCs) are being developed as oxygen and plasma volume-expanding therapeutics though their potential to promote oxidative tissue injury has raised safety concerns. Using a guinea pig exchange transfusion model, we examined the effects of polymerized bovine hemoglobin (HbG) on the transcriptional regulation, activity, and expression of the renal antioxidant enzy...

Considerable evidence suggests that oxidative stress plays a role in the pathogenesis of Parkinson's disease (PD), the most prevalent neurodegenerative movement disorder. Reduced expression of aldehyde dehydrogenase-1 (ALDH1) and glutathione peroxidase-1 (GPX1), enzymes that function to detoxify aldehydes and hydroxyl radicals, respectively, has been reported in the substantia nigra of patients...

Methylmercury (MeHg) toxicity is a continuous environmental problem to human health. The critical role of oxidative stress in the pathogenesis of MeHg cytotoxicity has been clarified, but the molecular mechanisms underlying MeHg-mediated oxidative stress remain to be elucidated. Here we demonstrate a post-transcriptional effect of MeHg on antioxidant selenoenzymes by using a MeHg-susceptible ce...

Recently, oxidative stress has been suggested as participating in the development of osteoporosis. Glutathione peroxidase 1 (GPX1) is one of antioxidant enzymes responsible for the defence of cells against oxidative damage and thus for protection against age related diseases such as osteoporosis. The aim of present study was to associate genetic variances of GPX1 enzyme with bone mineral densit...

BACKGROUND Dietary vitamin D3 (D3) restriction reduces paw grip endurance and motor performance in G93A mice, and increases inflammation and apoptosis in the quadríceps of females. ALS, a neuromuscular disease, causes progressive degeneration of motor neurons in the brain and spinal cord. OBJECTIVE We analyzed the spinal cords of G93A mice following dietary D3 restriction at 2.5% the adequate...

Neuronal degeneration due to oxidative stress (OS) has been proposed as a mechanism for tardive dyskinesia (TD) pathogenesis. Cellular defense mechanisms against OS may involve detoxification enzymes (e.g., glutathione peroxidase-1, GPX1; superoxide dismutase-2, SOD2 [also commonly known as MnSOD]; and glutathione S-transferase P1, GSTP1). Several pharmacogenetic studies have examined TD and OS...

Previous studies of mRNA for classical glutathione peroxidase 1 (GPx1) demonstrated that hepatocytes of rats fed a selenium-deficient diet have less cytoplasmic GPx1 mRNA than hepatocytes of rats fed a selenium-adequate diet. This is because GPx1 mRNA is degraded by the surveillance pathway called nonsense-mediated mRNA decay (NMD) when the selenocysteine codon is recognized as nonsense. Here, ...

BACKGROUND/AIMS Many patients with acute paraquat (PQ) intoxication die even at low PQ concentrations, whereas others with similar concentrations recover. Therefore, it is possible that individual differences in antioxidant capacity are responsible for the variable clinical outcome in patients with acute PQ intoxication. METHODS We investigated whether there was a relationship between the gen...

AIM To evaluate the effect of ginkgolide B treatment on vascular endothelial function in diabetic rats. METHODS The study included four groups with 15 male Sprague-Dawley rats: control group; control group treated with ginkgolide B; diabetic group; and diabetic treated with ginkgolide B. The activity of superoxide dismutase (SOD), malondialdehyde content, and nicotinamide adenine dinucleotide...

Insulin resistance, a hallmark of type 2 diabetes, is associated with oxidative stress. However, the role of reactive oxygen species or specific antioxidant enzymes in its development has not been tested under physiological conditions. The objective of our study was to investigate the impact of overexpression of glutathione peroxidase 1 (GPX1), an intracellular selenoprotein that reduces hydrog...