Search results for "OXIDATIVE STRESS"
showing 10 items of 1857 documents
Cytoprotective Effect of Idebenone through Modulation of the Intrinsic Mitochondrial Pathway of Apoptosis in Human Retinal Pigment Epithelial Cells E…
2022
Idebenone is a ubiquinone short-chain synthetic analog with antioxidant properties, which is believed to restore mitochondrial ATP synthesis. As such, idebenone is investigated in numerous clinical trials for diseases of mitochondrial aetiology and it is authorized as a drug for the treatment of Leber’s hereditary optic neuropathy. Mitochondria of retinal pigment epithelium (RPE) are particularly vulnerable to oxidative damage associated with cellular senescence. Therefore, the aim of this study was to explore idebenone’s cytoprotective effect and its underlying mechanism. We used a human-RPE cell line (ARPE-19) exposed to idebenone pre-treatment for 24 h followed by conditions …
Development and validation of new methods for the study of oxidative stress by Imaging Flow Cytometry
2017
El estrés oxidativo se origina debido a un desequilibrio entre la producción de especies reactivas de oxígeno (ROS) y los mecanismos celulares antioxidantes. Este desequilibrio en el estado normal redox puede causar efectos tóxicos a través de la producción de radicales libres y peróxidos, que dañan a componentes esenciales de la célula, como proteínas, lípidos y ADN. Actualmente se cree que el estrés oxidativo está relacionado con los mecanismos en un gran número de enfermedades degenerativas y cáncer, y también se le atribuye un papel importante en el proceso de envejecimiento. En algunos casos, la producción de especies reactivas de oxígeno (ROS) no es un fenómeno indeseable sino que for…
Plasma selenium levels and oxidative stress biomarkers: a gene-environment interaction population-based study.
2014
The role of selenium exposure in preventing chronic disease is controversial, especially in selenium-repleted populations. At high concentrations, selenium exposure may increase oxidative stress. Studies evaluating the interaction of genetic variation in genes involved in oxidative stress pathways and selenium are scarce. We evaluated the cross-sectional association of plasma selenium concentrations with oxidative stress levels, measured as oxidized to reduced glutathione ratio (GSSG/GSH), malondialdehyde (MDA), and 8-oxo-7,8-dihydroguanine (8-oxo-dG) in urine, and the interacting role of genetic variation in oxidative stress candidate genes, in a representative sample of 1445 men and women…
[35] Determination of oxidized glutathione in blood: High-performance liquid chromatography
1994
Publisher Summary The measurement of glutathione status is important in determining oxidative stress in tissues and biological fluids. The ratio of reduced to oxidized glutathione (GSH/GSSG) is a good indicator of the oxidative stress that may occur under physiological and pathological conditions. Changes in GSSG levels have been considered as intracellular signals able to modulate enzyme activity. Thus, it is important to have accurate methods to determine GSSG in biological fluids and in cells. In many cases, it is possible to use tissues, such as liver, muscle, or brain to determine GSH/GSSG. However, especially in human studies, samples from these tissues are not readily available; the …
Association of military training with oxidative stress and overreaching.
2011
ABSTRACT: We hypothesized that increased oxidative stress and disrupted redox balance may be predisposing factors and markers for overreaching (OR). Purpose: The study's purpose was to examine whether oxidative stress markers and antioxidant status and physical fitness are related to OR during an 8-wk military basic training (BT) period. Methods: Oxidative stress and antioxidant status were evaluated in the beginning and after 4 and 7 wk of training in 35 males (age = 19.7 ± 0.3 yr) at rest and immediately after a 45-min submaximal exercise. Physical activity (PA) was monitored by an accelerometer throughout BT. Indicators of OR were also examined. Results: From baseline to week 4, increase…
Defective copper transport in the copt5 mutant affects cadmium tolerance.
2014
Cadmium toxicity interferes with essential metal homeostasis, which is a problem for both plant nutrition and the consumption of healthy food by humans. Copper uptake is performed by the members of the Arabidopsis high affinity copper transporter (COPT) family. One of the members, COPT5, is involved in copper recycling from the vacuole toward the cytosolic compartment. We show herein that copt5 mutants are more sensitive to cadmium stress than wild-type plants, as indicated by reduced growth. Exacerbated cadmium toxicity in copt5 mutants is due specifically to altered copper traffic through the COPT5 transporter. Three different processes which have been shown to affect cadmium tolerance ar…
Stromal Interaction Molecule 1 (STIM1) Is Involved in the Regulation of Mitochondrial Shape and Bioenergetics and Plays a Role in Oxidative Stress
2012
Calcium ions are involved in a plethora of cellular functions including cell death and mitochondrial energy metabolism. Store-operated Ca(2+) entry over the plasma membrane is activated by depletion of intracellular Ca(2+) stores and is mediated by the sensor STIM1 and the channel ORAI1. We compared cell death susceptibility to oxidative stress in STIM1 knock-out and ORAI1 knockdown mouse embryonic fibroblasts and in knock-out cells with reconstituted wild type and dominant active STIM1. We show that STIM1 and ORAI1 deficiency renders cells more susceptible to oxidative stress, which can be rescued by STIM1 and ORAI1 overexpression. STIM1 knock-out mitochondria are tubular, have a higher Ca…
Oxidative Stress and DNA Damage in Human Gastric Carcinoma: 8-Oxo-7'8-dihydro-2'-deoxyguanosine (8-oxo-dG) as a Possible Tumor Marker
2013
We characterized the oxidative stress (OS) status by the levels of reduced/oxidized glutathione (GSH/GSSG), malondialdehyde (MDA) and the mutagenic base 8-oxo-7'8-dihydro-2'-deoxyguanosine (8-oxo-dG) in human gastric carcinoma (HGC) samples and compared the results with normal tissue from the same patients. We also analyzed 8-oxo-dG in peripheral mononuclear cells (PMNC) and urine from healthy control subjects and in affected patients in the basal state and one, three, six, nine and twelve months after tumor resection. The levels of DNA repair enzyme mRNA expression (hOGG1, RAD51, MUYTH and MTH1) were determined in tumor specimens and compared with normal mucosa. Tumor specimens e…
The NG2 Proteoglycan Protects Oligodendrocyte Precursor Cells against Oxidative Stress via Interaction with OMI/HtrA2.
2015
The NG2 proteoglycan is characteristically expressed by oligodendrocyte progenitor cells (OPC) and also by aggressive brain tumours highly resistant to chemo- and radiation therapy. Oligodendrocyte-lineage cells are particularly sensitive to stress resulting in cell death in white matter after hypoxic or ischemic insults of premature infants and destruction of OPC in some types of Multiple Sclerosis lesions. Here we show that the NG2 proteoglycan binds OMI/HtrA2, a mitochondrial serine protease which is released from damaged mitochondria into the cytosol in response to stress. In the cytosol, OMI/HtrA2 initiates apoptosis by proteolytic degradation of anti-apoptotic factors. OPC in which NG…
Relationship Between Oxidative Stress, ER Stress, and Inflammation in Type 2 Diabetes: The Battle Continues
2019
Type 2 diabetes (T2D) is a metabolic disorder characterized by hyperglycemia and insulin resistance in which oxidative stress is thought to be a primary cause. Considering that mitochondria are the main source of ROS, we have set out to provide a general overview on how oxidative stress is generated and related to T2D. Enhanced generation of reactive oxygen species (ROS) and oxidative stress occurs in mitochondria as a consequence of an overload of glucose and oxidative phosphorylation. Endoplasmic reticulum (ER) stress plays an important role in oxidative stress, as it is also a source of ROS. The tight interconnection between both organelles through mitochondrial-associated membranes (MAM…