Search results for "Oxidation-Reduction"
showing 10 items of 689 documents
Blood Glutathione as an Index of Radiation-Induced Oxidative Stress in Mice and Humans
1997
Abstract The effect of x-rays on GSH and GSSG levels in blood was studied in mice and humans. An HPLC method that we recently developed was applied to accurately determine GSSG levels in blood. The glutathione redox status (GSH/GSSG) decreases after irradiation. This effect is mainly due to an increase in GSSG levels. Mice received single fraction radiotherapy, at total doses of 1.0 to 7.0 Gy. Changes in GSSG in mouse blood can be detected 10 min after irradiation and last for 6 h within a range of 2.0–7.0 Gy. The highest levels of GSSG (20.1 ± 2.9 μ M), a 4.7-fold increase as compared with controls) in mouse blood are found 2 h after radiation exposure (5 Gy). Breast and lung cancer patien…
The insectivorous batPipistrellus nathusiiuses a mixed-fuel strategy to power autumn migration
2012
In contrast to birds, bats are possibly limited in their capacity to use body fat as an energy source for long migrations. Here, we studied the fuel choice of migratoryPipistrellus nathusii(approximate weight: 8 g) by analysing the stable carbon isotope ratio (δ13CV-PDB) of breath and potential energy sources. Breathδ13CV-PDBwas intermediate betweenδ13CV-PDBof insect prey and adipocyte triacylglycerols, suggesting a mixed-fuel use ofP. nathusiiduring autumn migration. To clarify the origin of oxidized fatty acids, we performed feeding experiments with captiveP. nathusii. After an insect diet, bat breath was enriched in13C relative to the bulk and fat portion of insects, but not deviating fr…
Effects of training on regional substrate oxidation in the hearts of ageing rats.
1989
23-month-old male rats were trained by running for 20 weeks. The oxidation rates of succinate, glutamate+malate, palmitoylcarnitine, and pyruvate and the activities of lactate dehydrogenase, citrate synthase, isocitrate dehydrogenase and cytochrome oxidase were measured in the subendocardium and subepicardium and in the right ventricle. Regional differences of substrate oxidation rates in the myocardium of old sedentary or trained rats were less than in young rats, suggesting that regional differences in the cardiac work load disappear during ageing. Training did not improve oxidation rates, in contradiction to some previous results.
Effect of Dietaryn-3Polyunsaturated Fatty Acids on Oxidant/Antioxidant Status in Macrosomic Offspring of Diabetic Rats
2014
The aim of this work was to determine the effect of dietaryn-3PUFA on oxidant/antioxidant status,in vitrovery low and low density lipoprotein (VLDL-LDL), and VLDL-LDL-fatty acid composition in macrosomic pups of diabetic mothers. We hypothesized thatn-3PUFA would improve oxidative stress in macrosomia. Diabetes was induced in female Wistar rats fed with the ISIO diet (control) or with the EPAX diet (enriched inn-3PUFAs), by streptozotocin. The macrosomic pups were killed at birth (day 0) and at adulthood (day 90). Lipid parameters and VLDL-LDL-fatty acid composition were investigated. The oxidant/antioxidant status was determined by measuring plasma oxygen radical absorbance capacity (ORAC)…
Kidney donors and kidney transplants have abnormal aminothiol redox status, and are at increased risk of oxidative stress and reduced redox buffer ca…
2013
Abstract Objective Living kidney donors have been part of a successful kidney transplant programme in Norway for almost 50 years. Glomerular filtration rates (GFRs) have tended to remain stable at about 70% of pre-donation levels. Plasma total homocysteine (Hcy) has an inverse relationship to kidney function, and previous reports indicate elevated levels of Hcy in kidney donors. We wanted to examine the most important plasma aminothiols in kidney donors, i.e. Hcy, cysteine (Cys) and cysteinylglycine (CG) with their redox species. The aminothiol redox-system appears to be an integral part of the extracellular antioxidant defence system in the body. Design and methods Plasma concentrations of…
Mitochondria from females exhibit higher antioxidant gene expression and lower oxidative damage than males
2003
We have investigated the differential mitochondrial oxidative stress between males and females to understand the molecular mechanisms enabling females to live longer than males. Mitochondria are a major source of free radicals in cells. Those from female rats generate half the amount of peroxides than those of males. This does not occur in ovariectomized animals. Estrogen replacement therapy prevents the effect of ovariectomy. Mitochondria from females have higher levels of reduced glutathione than those from males. Those from ovariectomized rats have similar levels to males, and estrogen therapy prevents the fall in glutathione levels that occurs in ovariectomized animals. Oxidative damage…
Exhaustive physical exercise causes oxidation of glutathione status in blood: Prevention by antioxidant administration
1992
We have studied the effect of exhaustive concentric physical exercise on glutathione redox status and the possible relationship between blood glutathione oxidation and blood lactate and pyruvate levels. Levels of oxidized glutathione (GSSG) in blood increase after exhaustive concentric physical exercise in trained humans. GSSG levels were 72% higher immediately after exercise than at rest. They returned to normal values 1 h after exercise. Blood reduced glutathione (GSH) levels did not change significantly after the exercise. We have found a linear relationship between GSSG-to-GSH and lactate-to-pyruvate ratios in human blood before, during, and after exhaustive exercise. In rats, physical…
Endurance training and antioxidants of lung
1984
Mice and rats were adjusted to daily treadmill training programs, which were heavy enough to increase the oxidative capacity of skeletal muscles. Endurance training did not affect the activities of catalase and glutathione peroxidase and the concentration of vitamin E in the lungs of mice and rats. Thus increased ventilation and oxygen utilization induced by exercise training do not modify lung antioxidants, in contrast to hyperoxia and hypoxia.
Is Autophagy Altered in the Leukocytes of Type 2 Diabetic Patients?
2015
It is unknown whether autophagy is altered in the leukocytes of type 2 diabetes (T2D) patients and whether oxidative and endoplasmic reticulum (ER) stresses regulate this mechanism. We studied anthropometric and metabolic parameters and evaluated oxidative stress, chromatin condensation, ER stress, and autophagy parameters in leukocytes of 103 T2D patients versus 109 sex- and age-matched controls. Patients showed increases in glucose, insulin, homeostasis model assessment of insulin resistance, and glycated hemoglobin (HbA1c) compared with controls (p < 0.001). Leukocytes displayed enhanced total and mitochondrial reactive oxygen species (ROS), reduced mitochondrial mass, and increased chro…
Effects of chlorpromazine and some of its metabolites on the EEG and on dopamine metabolism of the isolated perfused rat brain.
1979
Abstract The study concerned the effects of chlorpromazine (CPZ), monodesmethyl-chlorpromazine (NOR1-CPZ), didesmethyl-chlorpromazine (NOR2-CPZ), and chlorpromazine-N-oxide (CPZ-NO) on the EGG and on dopamine metabolism of the isolated perfused rat brain. Isolated brains were perfused with 100 ml of a perfusion medium containing 30% bovine red cells (v/v), 2 g bovine serum albumin, 14 mM glucose as well as one of the agents in a concentration of 10 μM. The main dopamine metabolite homovanillic acid (HVA) was measured fluorimetrically in the striatum of the isolated brain. The EGG was recorded by two symmetrical bipolar leads from the parietal regions at various times during the 30 min perfu…