Search results for "Oxidation."

Oxidative stress is related to frailty, not to age or sex, in a geriatric population

2017

Age-associated frailty is a geriatric syndrome. Frail individuals are vulnerable and lack capacity to manage external stressors. Frailty is associated with oxidative stress, but it has not been addressed in a large controlled human cohort. We aimed to ascertain whether indicators of oxidative damage to lipids and proteins are biomarkers of frailty, after adjusting for age, sex, and other possible confounders. We measured lipid and protein oxidation in the Toledo Study for Healthy Aging participants (N=742, aged 65–95), classified as frail, prefrail and nonfrail according to the Fried criteria. We found that age- and sex-adjusted levels of MDA and protein carbonylation in plasma proved to be…

Pharmacological properties of physical exercise in the elderly.

2013

Scientific evidence links physical activity to several benefits. Recently, we proposed the idea that exercise can be regarded as a drug. As with many drugs, dosage is of great importance. However, to issue a public recommendation of physical activity in aging is not an easy task. Exercise in the elderly needs to be carefully tailored and individualized with the specific objectives of the person or group in mind. The beneficial effects of exercise in two of the main age-related diseases, sarcopenia and Alzheimer's Disease, are dealt with at the beginning of this report. Subsequently, dosage of exercise and the molecular signaling pathways involved in its adaptations are discussed. Exercise a…

Metal concentrations and detoxification mechanisms in Solea solea and Solea senegalensis from NW Mediterranean fishing grounds

2013

10 pages, 5 figures, 4 tables

Impaired glutathione redox status is associated with decreased survival in two organophosphate-poisoned marine bivalves

2002

Biomonitoring organophosphate (OP) exposure in marine environments is generally achieved by the measurement of acetylcholinesterase activity in bivalves like mussels. However, there is evidence that indicates that oxidative stress may be implied in OP toxicity. The aim of this study was to evaluate the relationship between survival from the OP insecticide fenitrothion and glutathione levels in marine bivalves. Mussels (Mytilus galloprovincialis Lam.) and scallops (Flexopecten flexuosus Poli) were exposed, in a time to death test, to their LC85 of fenitrothion for 96 h. OP-poisoned mussels showed reduced (GSH) and oxidised (GSSG) glutathione depletion in the digestive gland, muscle and gills…

Maintenance of GSH content in primary astrocyte cultures under oxidative stress conditions.

1993

Deciphering metal-induced oxidative damages on glycated albumin structure and function

2014

Background: Metal ions such as copper or zinc are involved in the development of neurodegenerative pathologies and metabolic diseases such as diabetes mellitus. Albumin structure and functions are impaired following metal-and glucose-mediated oxidative alterations. The aim of this study was to elucidate effects of Cu(II) and Zn(II) ions on glucose-induced modifications in albumin by focusing on glycation, aggregation, oxidation and functional aspects. Methods: Aggregation and conformational changes in albumin were monitored by spectroscopy, fluorescence and microscopy techniques. Biochemical assays such as carbonyl, thiol groups, albumin-bound Cu, fructosamine and amine group measurements w…

Thermal aggregation of glycated bovine serum albumin

2010

International audience; Aggregation and glycation processes in proteins have a particular interest in medicine fields and in food technology. Serum albumins are model proteins which are able to self-assembly in aggregates and also sensitive to a non-enzymatic glycation in cases of diabetes. In this work, we firstly reported a study on the glycation and oxidation effects on the structure of bovine serum albumin (BSA). The experimental approach is based on the study of conformational changes of BSA at secondary and tertiary structures by FTIR absorption and fluorescence spectroscopy, respectively. Secondly, we analysed the thermal aggregation process on BSA glycated with different glucose con…

Functional citric acid cycle in an arcA mutant of Escherichia coli during growth with nitrate under anoxic conditions

1998

The operation of the citric acid cycle of Escherichia coli during nitrate respiration (anoxic conditions) was studied by measuring end products and enzyme activities. Excretion of products other than CO2, such as acetate or ethanol, was taken as an indication for a non-functional cycle. From glycerol, approximately 0.3 mol acetate was produced; the residual portion was completely oxidized, indicating the presence of a partially active citric acid cycle. In an arcA mutant devoid of the transcriptional regulator ArcA, glycerol was completely oxidized with nitrate as an electron acceptor, demonstrating derepression and function of the complete pathway. Glucose, on the other hand, was excreted …

Specific stress-induced storage of trehalose, glycerol and D-arabitol in response to oxidative and osmotic stress in Candida albicans.

2012

Candida albicans exponential yeast cells are able to face environmental challenges by mounting a rapid and efficient "general stress response". Here we show that one of the main components of this response consists of the intracellular protective accumulation of the non-reducing disaccharide trehalose and two polyols, glycerol and D-arabitol, an accumulation that occurs in a stress-specific dependent manner. Thus, oxidative exposures promoted a marked increase in both trehalose and D-arabitol in the wild type strain, RM-100, whereas the glycerol content remained virtually unaffected with respect to basal levels. In contrast, osmotic challenges induced the significant storage of glycerol acc…

Modeling of the process of moisture loss during the storage of dried apricots

2011

[EN] Moisture content is a reference parameter for dried food because the growth of most microorganisms is inhibited below certain water activity levels. In addition, it has a determining influence on the evolution of important parameters, such as color and flavor, and on other properties and deterioration reactions, such as texture, oxidation processes and nutritional value. During the storage of some dried fruits, moisture is produced due to Maillard reactions and exchanged with the surrounding environment through the packaging. The evolution of dried foods during their shelf life depends on the storage conditions. The aim of this study is to analyze the evolution of the moisture content …