Search results for "REACTIVE OXYGEN SPECIES"
showing 10 items of 879 documents
Different patterns of in vivo pro-oxidant states in a set of cancer- or aging-related genetic diseases
2008
A comparative evaluation is reported of pro-oxidant states in 82 patients with ataxia telangectasia (AT), Bloom syndrome (BS), Down syndrome (DS), Fanconi anemia (FA), Werner syndrome (WS), and xeroderma pigmentosum (XP) vs 98 control donors. These disorders display cancer proneness, and/or early aging, and/or other clinical features. The measured analytes were: (a) leukocyte and urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG), (b) blood glutathione (GSSG and GSH), (c) plasma glyoxal (Glx) and methylglyoxal (MGlx), and (d) some plasma antioxidants [uric acid (UA) and ascorbic acid (AA)]. Leukocyte 8-OHdG levels ranked as follows: WS>BS approximately FA approximately XP>DS approximately AT appr…
Effect of exercise training on in vitro LDL oxidation and free radical-induced hemolysis: the HERITAGE Family Study.
2006
Oxidant stress and overproduction of reactive oxygen species (ROS) contribute to the development of cardiovascular disease. Oxidative modifications of low-density lipoproteins (LDL) are thought to play an early and critical role in atherogenesis. LDL oxidation can be reproduced in vitro, but results usually show a large interindividual variation not entirely explained by the environment. Free radical-induced hemolysis is also proposed to reveal the overall antioxidant capacity. The roles of genetic factors and exercise on the variability of both measures were investigated. The study was conducted in 146 healthy individuals from 28 families participating in a 20-week exercise-training progra…
Oxidative stress markers in the neocortex of drug-resistant epilepsy patients submitted to epilepsy surgery
2013
Summary Purpose While there is solid experimental evidence of brain oxidative stress in animal models of epilepsy, it has not been thoroughly verified in epileptic human brain. Our purpose was to determine and to compare oxidative stress markers in the neocortex of epileptic and non-epileptic humans, with the final objective of confirming oxidative stress phenomena in human epileptic brain. Methods Neocortical samples from drug-resistant epilepsy patients submitted to epilepsy surgery ( n =20) and from control, non-epileptic cortex samples ( n =11) obtained from brain bank donors without neurological disease, were studied for oxidative stress markers: levels of reactive oxygen species (ROS)…
Age, homocysteine, and oxidative stress: Relation to hypertension and type 2 diabetes mellitus
2010
Abstract OBJECTIVES: Hyperhomocysteinemia and oxidative stress are independent risk factors for cardiovascular events, which occur more frequently in old age. We evaluated these parameters in relation to age and the presence of hypertension and type 2 diabetes mellitus. METHODS: Two hundred eighty-two subjects (female/male: 142/140; 141 were >65 years and 141 were <65 years; mean age 73.9 +/- 6.6 years and 52.5 +/- 8.2 years, respectively) were randomly recruited from those attending our institution. Blood pressure, anthropometric parameters, oxidative stress parameters (reactive oxygen species [ROS] and malondialdehyde [MDA]), and homocysteine levels were evaluated in participants. RESULTS…
Limb Ischemic Conditioning Induces Oxidative Stress Followed by a Correlated Increase of HIF-1α in Healthy Volunteers.
2019
Background Local and remote ischemic preconditioning has been used as a protective intervention against ischemia/reperfusion (I/R) damage in several preclinical and clinical studies. However, its physiological mechanisms are not completely known. I/R increases the production of reactive oxygen species, which also serve as messengers for a variety of functions. Hypoxia-inducible factor 1 alpha (HIF-1α) is probably the most important transcription factor mediator of hypoxic signaling. Objective We hypothesized that limb ischemic conditioning (LIC) induces a local oxidative/nitrosative stress and a correlated increase of HIF-1α plasma levels. Methods An observational, prospective, and single-c…
Effects of acute exercise and xanthine oxidase inhibition on novel cardiovascular biomarkers.
2013
Several sports have been associated with a postexercise increase of cardiac, liver, and skeletal muscle biomarkers of injury. Exhaustive or acute physical exercise causes an increased generation of reactive oxygen species, resulting in cellular injury. Thus, exercise and training may trigger pathophysiological changes in serum concentrations of a variety of biomarkers. In this study, we aimed to evaluate the variation of novel biomarkers of stress and cardiovascular disease such as copeptin, midregional part of proadrenomedullin (MR-proADM), growth differentiation factor 15 (GDF15), soluble vascular endothelial growth factor receptor, and placental growth factor along with uric acid before …
Impact of Fruit Beverage Consumption on the Antioxidant Status in Healthy Women
2008
<i>Background:</i> Epidemiologic studies suggest that antioxidant-rich foods might reduce the risk of cancer and cardiovascular diseases. <i>Aim:</i> To test the health-protective potential of three fruit beverages, Fb (grape-orange-apricot), FbM (Fb with skimmed milk) and FbMFe [FbM + Fe(II)], in healthy women. <i>Methods:</i> The influence of fruit beverage consumption (500 ml/day) upon serum antioxidant capacity determined by ORAC and TEAC methods and erythrocyte superoxide dismutase (SOD) activity was assessed in 32 healthy female volunteers. In the intervention study, each subject received the fruit beverages during three periods (3 weeks for Fb and …
Oxidant mechanisms in childhood obesity: the link between inflammation and oxidative stress.
2011
Evidence of obesity-induced oxidative stress in adults has emerged in the past several years, and similar evidence has been demonstrated in children more recently. The reactive species of oxygen or nitrogen can chemically alter all major classes of biomolecules by modifying their structure and function. Organisms have developed mechanisms to protect biomolecules from the deleterious effects of free radicals. These include the enzymes superoxide dismutase, catalase, and glutathione peroxidase, as well as water and lipid-soluble antioxidants, such as glutathione, ascorbate (vitamin C), α-tocopherol (vitamin E), and β-carotene. Obesity creates oxidant conditions that favor the development of c…
Induction of oxidative stress and human leukocyte/endothelial cell interactions in polycystic ovary syndrome patients with insulin resistance.
2011
Insulin resistance is a feature of polycystic ovary syndrome (PCOS) and is related to mitochondrial and endothelial function.We tested whether hyperandrogenic insulin-resistant women with PCOS, who have an increased risk of vascular disease, display impaired leukocyte-endothelium interactions, and mitochondrial dysfunction.This was a prospective controlled study conducted in an academic medical center.The study population consisted of 43 lean reproductive-age women with PCOS and 39 controls subjects.We evaluated anthropometric and metabolic parameters, adhesion molecules, and interactions between leukocytes and human umbilical vein endothelial cells. Mitochondrial function was studied by as…
Effects of metformin on mitochondrial function of leukocytes from polycystic ovary syndrome patients with insulin resistance.
2015
ObjectiveOxidative stress and mitochondrial dysfunction are implicated in polycystic ovary syndrome (PCOS). The present study assesses the effect of metformin treatment on mitochondrial function in polymorphonuclear cells from PCOS subjects. Additionally, we evaluate endocrine parameters and levels of interleukin 6 (IL6) and tumour necrosis factor alpha (TNFα).Design and methodsOur study population was comprised of 35 women of reproductive age diagnosed with PCOS and treated with metformin for 12 weeks, and their corresponding controls (n=41), adjusted by age and BMI. We evaluated the alteration of endocrinological and anthropometrical parameters and androgen levels. Mitochondrial O2 consum…