Search results for "DASE"

Oxidative stress and enzymatic antioxidant mechanisms in essential hypertension

2001

Age-related changes in antioxidant status and oxidative damage to lipids and dna in mitochondria of rat liver

2005

To investigate the correlation between oxidative stress and mitochondrial damage with aging, antioxidant system, levels of oxidative DNA damage and as an index of the loss of plasma membrane integrity lipid peroxidation and membrane potential were studied. Results showed that the activities of antioxidant enzymes superoxide dismutase (SOD) and catalase significantly decreased during aging, however glutathione peroxidase (GSH-PX) increased in the aged mitochondria and glutathione (GSH) did not change during aging. No statistical difference was observed in the lipid peroxidation of mitochondria between young and old animals. The level of oxidative DNA damage (measured as 8oxo-dG) tended to in…

Sex Differences in Mitochondrial Antioxidant Gene Expression

2020

Females live longer than males. This could be in part due to the higher levels of estrogens in females, which protect them against aging. Physiological concentrations of estrogens have antioxidant effects as they induce the expression of manganese superoxide dismutase and glutathione peroxidase by stimulating estrogen receptors and the mitogen-activated protein kinase and nuclear factor kappa B pathways. However, estrogens can have undesirable effects such as they are feminizing to males, so other alternatives need to be searched. Phytoestrogens are good candidates as they can also bind to estrogens receptors, and in fact, they are able to mimic the antioxidant properties of estrogens. It i…

Glutathione Peroxidase-1 and Homocysteine for Cardiovascular Risk Prediction

2005

Objectives This prospective study was designed to evaluate the effect of joint determination of two important contrary biomarkers—homocysteine and glutathione peroxidase (GPx)-1—on cardiovascular risk stratification. Background Homocysteine plasma levels have been associated with cardiovascular risk. Experimental data suggest that antioxidative GPx-1 activity modulates cardiovascular risk associated with homocysteine. Methods In 643 patients with coronary artery disease, we performed a prospective study to assess the risk of homocysteine plasma levels and GPx-1 activity on long-term cardiovascular risk with a median follow-up of 7.1 years. Results Both homocysteine and GPx-1 were among the …

Concentration-Dependent Antioxidant/Pro-Oxidant Activity of Ascorbic Acid in Chickens

2012

С vitamīns piedalās daudzos vielmaiņas procesos. Tas stiprina organisma imūnsistēmu, piedalās bioloģiskās oksidēšanās un reducēšanās procesos. Askorbīnskābe un dehidroaskorbīnskābe veido redoks sistēmu un ir saistītas ar glutationa sistēmu. Dažādu stresu ietekmē askorbīnskābes koncentrācija audos samazinās. Tādēļ barību vajag bagātināt ar šo vitamīnu. Darba mērķis bija pētīt dažādus oksidatīvā stresa biomarķierus cāļu organismā, kadmija akumulāciju orgānos, imūnsistēmas aktivitāti un nieru funkcijas izmaiņas askorbīnskābes ietekmē atkarībā no tās koncentrācijas barībā. Eksperimentos izmantojām vienu dienu vecus Lohmann Brown gailīšus, kurus sadalījām piecās analogās grupās. Cāļi saņēma komb…

Early reductive stress followed by a late onset oxidative stress in acute myocardial infarction

2018

Introduction The idea that the cells might suffer from reductive rather than oxidative stress and that such stress may be relevant in pathophysiology has gained momentum. Aim We aimed at studying markers of oxidative stress and damage as well as the expression of antioxidant enzymes in a swine model of acute myocardial infarction (AMI) followed by reperfusion. Results and Discussion We found an increase in the GSH to GSSG ratio, a decrease in protein glutathionylation and a decrease in p38 MAPK phosphorylation after 90 minutes of ischaemia in heart samples. It was accompanied by an increase in the expression of Thioredoxin (TrX) and Peroxiredoxin (PrX) and a decrease in the expression of Gl…

Exercise as an antioxidant: it up-regulates important enzymes for cell adaptations to exercise

2006

Abstract Aims. – To assess the role of the reactive oxygen species (ROS) in cell signalling and in the regulation of gene expression. Methods. – Exercise causes oxidative stress only when exhaustive. Strenuous exercise causes oxidation of glutathione, release of cytosolic enzymes, and other signs of cell damage. We have tested this hypothesis by studying the effect of inhibition of ROS production by allopurinol (an inhibitor of xanthine oxidase, a free radical generating enzyme) on cell signalling pathways in marathon runners and in rats submitted to exhaustive exercise by running on a treadmill. Results. – Exercise caused an activation of NF-κB in lymphocytes from marathon runners which wa…

Oxygen Radical Scavengers

2010

The myocardium can tolerate only relatively short periods of total myocardial ischemia without myocardial cell death. Following short ischemic periods, ischemic damage is reversible by reperfusion. However, with increasing duration and severity of ischemia, the damage inflicted to cardiomyocytes following reperfusion becomes irreversible. The combined pathologic events in the myocardium that follow a critical period of ischemia and leading to either reversible or irreversible damage to both cardiomyocytes and cardiac microvasculature is known as ischemia-reperfusion injury (Goldhaber and Weiss 1992).

Nitroglycerin-Induced Endothelial Dysfunction and Tolerance Involve Adverse Phosphorylation and S -Glutathionylation of Endothelial Nitric Oxide Synt…

2011

Objective— Continuous administration of nitroglycerin (GTN) causes tolerance and endothelial dysfunction by inducing reactive oxygen species (ROS) production from various enzymatic sources, such as mitochondria, NADPH oxidase, and an uncoupled endothelial nitric oxide synthase (eNOS). In the present study, we tested the effects of type 1 angiotensin (AT 1 )-receptor blockade with telmisartan on GTN-induced endothelial dysfunction in particular on eNOS phosphorylation and S -glutathionylation sites and the eNOS cofactor synthesizing enzyme GTP–cyclohydrolase I. Methods and Results— Wistar rats were treated with telmisartan (2.7 or 8 mg/kg per day PO for 10 days) and with GTN (50 mg/kg per d…

Effects of strength and endurance training on antioxidant enzyme gene expression and activity in middle-aged men

2007

This study was aimed at investigating the effects of a 21-week period of progressive strength or endurance training on peripheral blood mononuclear cells (PBMC) antioxidant enzyme gene expression and activity in healthy middle-aged untrained men. Strength (n=11) and endurance (n=12) training were performed twice a week, including resistance exercises to activate all the main muscle groups or cycle-ergometer pedaling, respectively. mRNA levels of catalase, glutathione peroxidase (GPx), mitochondrial superoxide dismutase (MnSOD) and cytosolic superoxide dismutase (CuZnSOD) were increased after 21 weeks of strength training, while endurance training induced significant changes only in MnSOD an…