Search results for "Oxidants"
showing 10 items of 878 documents
Dietary antioxidant supplementation did not affect declining sperm function with age in the mouse but did increase head abnormalities and reduced spe…
1998
The present study aims to ascertain whether dietary administration of a mixture of vitamins C and E may prevent the negative effects of paternal age on male fertility variables in the mouse. Experimental males were fed a standard diet supplemented with either a low or high dose of vitamins C and E. Oocytes enclosed in cumulus masses were inseminated using a 2 x 2 factorial design established according to whether males were young (3-4 months of age) or aged (22-24 months of age) and whether they were fed a control or antioxidant diet. Aged males showed a significant decrease in number of spermatozoa/mg epididymis when compared to young males. Dietary supplementation with low doses of vitamin…
Inverse association of vitamin C with cataract in older people in India.
2011
OBJECTIVE: To examine the association between vitamin C and cataract in the Indian setting. DESIGN: Population-based cross-sectional analytic study. PARTICIPANTS: A total of 5638 people aged ≥60 years. METHODS: Enumeration of randomly sampled villages in 2 areas of north and south India to identify people aged ≥60 years. Participants were interviewed for socioeconomic and lifestyle factors (tobacco, alcohol, household cooking fuel, work, and diet); attended a clinical examination, including lens photography; and provided a blood sample for antioxidant analysis. Plasma vitamin C was measured using an enzyme-based assay in plasma stabilized with metaphosphoric acid, and other antioxidants wer…
Changes in glutathione status and the antioxidant system in blood and in cancer cells associate with tumour growth in vivo
1999
The relationship among cancer growth, the glutathione redox cycle and the antioxidant system was studied in blood and in tumour cells. During cancer growth, the glutathione redox status (GSH/GSSG) decreases in blood of Ehrlich ascites tumour-bearing mice. This effect is mainly due to an increase in GSSG levels. Two reasons may explain the increase in blood GSSG: (a) the increase in peroxide production by the tumour that, in addition to changes affecting the glutathione-related and the antioxidant enzyme activities, can lead to GSH oxidation within the red blood cells; and (b) an increase of GSSG release from different tissues into the blood. GSH and peroxide levels are higher in the tumour …
TORC1 Inhibition by Rapamycin Promotes Antioxidant Defences in a Drosophila Model of Friedreich’s Ataxia
2015
Friedreich's ataxia (FRDA), the most common inherited ataxia in the Caucasian population, is a multisystemic disease caused by a significant decrease in the frataxin level. To identify genes capable of modifying the severity of the symptoms of frataxin depletion, we performed a candidate genetic screen in a Drosophila RNAi-based model of FRDA. We found that genetic reduction in TOR Complex 1 (TORC1) signalling improves the impaired motor performance phenotype of FRDA model flies. Pharmacologic inhibition of TORC1 signalling by rapamycin also restored this phenotype and increased the lifespan and ATP levels. Furthermore, rapamycin reduced the altered levels of malondialdehyde + 4-hydroxyalke…
Retinol-Binding Protein 4 Levels Are Associated with Measures of Liver and Renal Function and Oxidant/Antioxidant Status in Obese Children
2013
Serum retinol-binding protein 4 (RBP4) has been proposed as a metabolic risk factor in obesity. We found that RBP4 levels also were associated with liver enzymes and cystatin C. Oxidant stress is a significant feature in obese children with greater values of RBP4 that can mediate the development of comorbidities.
Effect of aging on metabolic zonation in rat liver: acinar distribution of GSH metabolism.
1992
The effect of age on the glutathione antioxidant system and its acinar distribution in rat liver was studied. GSH/GSSG ratio in blood and liver was lower in old than in young rats. Hepatic glutathione peroxidase and glutathione S-transferase activities were higher in old than in young rats, whereas hepatic gamma-glutamyl transpeptidase activity was lower in old than in young rats. Glutathione reductase and glucose-6-phosphate dehydrogenase activities did not change with age in rat liver. Total glutathione levels and glutathione peroxidase activity were higher in periportal than in perivenous areas of young rats, but this heterogeneous distribution did not occur in old rats. No change with a…
Growth hormone replacement therapy prevents sarcopenia by a dual mechanism: improvement of protein balance and of antioxidant defenses.
2013
The aim of our study was to elucidate the role of growth hormone (GH) replacement therapy in three of the main mechanisms involved in sarcopenia: alterations in mitochondrial biogenesis, increase in oxidative stress, and alterations in protein balance. We used young and old Wistar rats that received either placebo or low doses of GH to reach normal insulin-like growth factor-1 values observed in the young group. We found an increase in lean body mass and plasma and hepatic insulin-like growth factor-1 levels in the old animals treated with GH. We also found a lowering of age-associated oxidative damage and an induction of antioxidant enzymes in the skeletal muscle of the treated animals. GH…
Is obesity associated with oxidative stress in children?
2009
We evaluated the presence of oxidative stress in obese children without co-morbidities.The study population included 68 children (30 girls, 38 boys), between 6 and 14 years of age. The levels of markers of oxidative damage (malondialdehyde [MDA], and plasma carbonyl groups [CG]) and measures of antioxidant defense, such as the enzyme glutathione peroxidase (GPx) and low molecular scavengers (erythrocyte-reduced glutathione [GSH], alpha-tocopherol and beta-carotene) were determined. Children were categorized in groups by the standard deviation score of body mass index (SDS-BMI). Twenty children were non-obese (SDS-BMIor =1.33), and the 48 obese children (SDS-BMIor =2) were further divided in…
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)…
Iridoid extracts from Ajuga iva increase the antioxidant enzyme activities in red blood cells of rats fed a cholesterol-rich diet.
2010
The lyophilized aqueous extract of Ajuga iva (Ai) is able to reduce oxidative stress, which may prevent lipid peroxidation in hypercholesterolemic rats. Iridoids (I) were isolated from Ai. We hypothesized that the antioxidant defense status in red blood cells (RBC) and tissues in rats fed a cholesterol-rich diet and treated with Ai may be correlated to these compounds. Male Wistar rats (n = 32) weighing 120 +/- 5 g were fed a diet containing 1% cholesterol for 15 days. After this phase, hypercholesterolemic (HC) rats were divided into groups, fed the same diet, and received either the same or different doses (5, 10, or 15 mg/kg body weight by intraperitoneal injection) of I for 15 days. Com…