Search results for "thione"
showing 10 items of 865 documents
Pancreatic islets from non-heart beating donor pig: Two-layer preservation method in an in vitro porcine model
2011
Purpose Pancreata from non-heart beating donors could represent an unlimited source of islets if their cell viability can be efficiently preserved during the time necessary to process the organs by the use of a better solution of preservation compared to the classic University of Wisconsin solution. The aim of this study was to determine whether it is possible to obtain functioning “alive islets” from non-heart-beating donors by comparing, on a porcine model, the classic “UW ice-store” method with a two-layer cold storage method (TLM) using oxygenated Perfluorocarbons (PFC) and UW. Methods Whole pancreata were harvested from 20 NHBDs female pigs with similar characteristics and preserved fo…
Ischemic type biliary lesions in histidine-tryptophan-ketoglutarate (HTK) preserved liver grafts.
2006
Ischemic type biliary lesions lead to considerable morbidity following orthotopic liver transplantation. The exact pathogenesis is unknown. One major hypothesis is that insufficient perfusion of the arterial vessels of the biliary tree, especially under perfusion with the high viscous University of Wisconsin solution, might be responsible for ischemic type biliary lesions. Due to low viscosity, HTK solution is reported to have a lower incidence of biliary complications. However, there is no data concerning ischemic type biliary lesions in HTK preserved livers. In this paper we report our results after orthotopic liver transplantation with special regard to ischemic type biliary lesions in …
N-acetylcysteine protects against age-related increase in oxidized proteins in mouse synaptic mitochondria.
1997
Since it has been proposed that oxidized protein accumulation plays a critical role in brain aging, we have investigated the effect of a thiolic antioxidant on protein carbonyl content in synaptic mitochondria from female OF-1 mice. At 48 weeks of age, a control group was fed standard food pellets and another group received pellets containing 0.3% (w/w) of N-acetylcysteine. A 24-week treatment resulted in a significant decrease in protein carbonyl content in synaptic mitochondria of the N-acetylcysteine-treated animals as compared to age-matched controls.
Glucose 6-P dehydrogenase delays the onset of frailty by protecting against muscle damage.
2021
Background: Frailty is a major age-associated syndrome leading to disability. Oxidative damage plays a significant role in the promotion of frailty. The cellular antioxidant system relies on reduced nicotinamide adenine dinucleotide phosphate (NADPH) that is highly dependent on glucose 6-P dehydrogenase (G6PD). The G6PD-overexpressing mouse (G6PD-Tg) is protected against metabolic stresses. Our aim was to examine whether this protection delays frailty. Methods: Old wild-type (WT) and G6PD-Tg mice were evaluated longitudinally in terms of frailty. Indirect calorimetry, transcriptomic profile, and different skeletal muscle quality markers and muscle regenerative capacity were also investigate…
LSC Abstract – Increased oxidative stress leads to telomere shortening in children with alpha-1 antitrypsin deficiency
2016
Background: Oxidative stress (OS) is involved in the pathophysiology of AATD (Escribano A. et al. Thorax 2015; 70:82-3). In addition, it has been shown that OS accelerates telomere shortening which is associated to higher emphysema risk in COPD patients. Rationale and aims: Since AATD is characterised by chronic OS, we hypothesise that telomere shortening would be accelerated in AATD patients and would be associated with higher risk of developing lung disease. This study is aimed to assess the OS profile, the enzymatic antioxidant defence mechanisms and telomere length (TL) in children with AATD and to study its association with AAT phenotypes. Methods: OS parameters, the activity of the ma…
The Activation Pattern of the Antioxidant Enzymes in the Right Ventricle of Rat in Response to Pressure Overload is of Heart Failure Type
2003
In the left ventricle subjected to pressure overload activity, the antioxidant enzymes increased at the hyperfunctional stage. During the transition to heart failure, these enzymes are down-regulated, oxidative stress increases, and apoptosis progresses. Maladaptative activation of the antioxidant enzymes at an early stage may contribute to the intrinsic vulnerability of right ventricle to pressure overload. The authors studied changes in expression and activity of the enzymes manganese and copper-zinc superoxide dismutases, glutathione peroxidase, and catalase in the right ventricle of rat following induction of pulmonary hypertension by injection of monocrotaline. Increase in the manganes…
Effect of a Diet Supplemented with alpha-Tocopherol and beta-Carotene on ATP and Antioxidant Levels after Hepatic Ischemia-Reperfusion.
2008
Ischemia-reperfusion injury associated with liver transplantation remains a serious complication in clinical practice. In the present study the effect of intake of alpha-tocopherol or beta-carotene to limit liver injury by oxidative stress in ischemia and reperfusion was explored. Wistar rats were fed with diets enriched with alpha-tocopherol (20 mg/day) or beta-carotene (3 mg/day) for 21 days. After 21 days, their livers were subjected to 15 and 30 min of ischemia and afterwards were reperfused for 60 min. The recovery of levels of ATP during reperfusion was better in the group of rats whose diets were supplemented with alpha-tocopherol or beta-carotene than in the group control. The suppl…
Redox modulation of mitochondriogenesis in exercise. Does antioxidant supplementation blunt the benefits of exercise training?
2015
Physical exercise increases the cellular production of reactive oxygen species (ROS) in muscle, liver, and other organs. This is unlikely due to increased mitochondrial production but rather to extramitochondrial sources such as NADPH oxidase or xanthine oxidase. We have reported a xanthine oxidase-mediated increase in ROS production in many experimental models from isolated cells to humans. Originally, ROS were considered as detrimental and thus as a likely cause of cell damage associated with exhaustion. In the past decade, evidence showing that ROS act as signals has been gathered and thus the idea that antioxidant supplementation in exercise is always recommendable has proved incorrect.…
Oxidative stress in vascular disease and its pharmacological prevention
2013
Cardiovascular risk factors lead to enhanced production of reactive oxygen species (ROS) generated by NADPH oxidase, xanthine oxidase (XO), the mitochondrial electron-transport chain (ETC), and dysfunctional endothelial nitric oxide synthase (eNOS). When the capacity of antioxidant defense systems [e.g., superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), heme oxygenase (HO), paraoxonase (PON)] is exceeded, this results in oxidative stress, which can promote atherogenesis. Therefore, pharmacological means to prevent oxidative stress are of major therapeutic interest. Some established drugs and novel therapeutic approaches can prevent oxidative stress and, presumably, vascula…
Overexpression of G6PD as a model of robustness
2018
Introduction Frailty is a major geriatric syndrome that has been associated to oxidative stress. The antioxidant system is largely based on the reducing power of NADPH, whose levels are mainly determined by the enzyme glucose-6-phosphate dehydrogenase (G6PD). Material and methods Using old female Tg-mice overexpressing G6PD (18 to 26 months old), we measured frailty and different muscle parameters: oxidative stress, cross-sectional area (CSA), markers regulating protein synthesis, mitochondrial dynamics, and apoptosis. Results Our results show that 18–24 months old G6PD-Tg animals performed better in the motor coordination and grip strength test than the WT. We also found lower changes in b…