Search results for " STRESS"
showing 10 items of 3936 documents
Oral administration of vitamin C decreases muscle mitochondrial biogenesis and hampers training-induced adaptations in endurance performance
2008
Background Exercise practitioners often take vitamin C supplements because intense muscular contractile activity can result in oxidative stress, as indicated by altered muscle and blood glutathione concentrations and increases in protein, DNA, and lipid peroxidation. There is, however, considerable debate regarding the beneficial health effects of vitamin C supplementation. Objective This study was designed to study the effect of vitamin C on training efficiency in rats and in humans. Design The human study was double-blind and randomized. Fourteen men (27-36 y old) were trained for 8 wk. Five of the men were supplemented daily with an oral dose of 1 g vitamin C. In the animal study, 24 mal…
The influence of micronutrients on oral and general health
2011
Abstract Objective The aim of the present clinical pilot study was to examine the influence of a combination of micronutrients on individuals with high stress experience. Methods 40 healthy students (28 female, 12 male) with a mean age of 27.1 ± 3.0 years, experiencing high examination stress, were chosen. After approval of the ethics commission, one group of students (n = 19) took a combination of micronutrients (Orthomol vital m/f) for three months, whereas other students (n = 21) served as control group. All participants underwent at the beginning and at the end of the trial a dental examination, a determination of 10 periodontal pathogens, a salivary and a blood analysis. In addition, t…
Antioxidant Activity of Vitamin A within Lipid Environments
1998
New information about deleterious effects of free radicals on cell compartments, and a growing amount of associations between free radicals and various pathological conditions, have produced considerable interest in the biological defense systems against oxidative injury. The antioxidant properties of vitamin A, known for decades (Monaghan and Schmitt, 1932), have been reinvestigated in recent years in chemical as well as in biological systems. Its lipid nature and the localization within the lipophilic compartment of membranes and lipoproteins make vitamin A effective in reducing lipid peroxidation by acting as a chain-breaking antioxidant.
Vitamin A deficiency alters rat lung alveolar basement membrane: reversibility by retinoic acid.
2010
Vitamin A is essential for lung development and pulmonary cell differentiation and its deficiency results in alterations of lung structure and function. Basement membranes (BMs) are also involved in those processes, and retinoic acid, the main biologically active form of vitamin A, influences the expression of extracellular matrix macromolecules. Therefore, we have analyzed the ultrastructure and collagen content of lung alveolar BM in growing rats deficient in vitamin A and the recovering effect of all-trans retinoic acid. Male weanling pups were fed a retinol-adequate or -deficient diet until they were 60 days old. A group of vitamin A-deficient pups were recovered by daily intraperitonea…
alpha-Tocopherol, MDA-HNE and 8-OHdG levels in liver and heart mitochondria of adriamycin-treated rats fed with alcohol-free beer.
2008
Different studies indicate that oxidative stress and mitochondrial damage are key factors in different pathogenic process. The aim of this study was to investigate the possible protective role of alcohol-free beer on adriamycin-induced (ADR) heart and liver toxicity using biomarkers of oxidative stress. This effect was compared with the effect of alcohol beer intake and with a control group. Rats were randomly divided into six groups. The first group received no adriamycin, was fed with water and was regarded as the control group; the second group was injected with a ADR (two cycles of 5mg/kg); the third and fourth groups were fed with alcohol-free and beer for 21 days, respectively and the…
Vitamin A deficiency causes oxidative damage to liver mitochondria in rats.
2000
Mitochondrial damage in rat liver induced by chronic vitamin A-deficiency was studied using three different groups of rats: (i) control rats, (ii) rats fed a vitamin A-free diet until 50 d after birth and (iii) vitamin A-deficient rats re-fed a control diet for 30 d. No statistical difference in body weight and food intake was found between control and vitamin A-deficient rats. Liver GSH concentration was similar in both groups. However, in vitamin A-deficient rats, the mitochondrial GSH/GSSG ratio was significantly lower and the levels of malondialdehyde (MDA) and 8-oxo-7, 8-dihydro-2'-deoxyguanosine (oxo8dG) were higher when compared to control rats. These values were partially restored i…
Intraoperative alteration of the total clearance of ascorbic acid in plasma
2003
Ascorbic acid (AA) is an important antioxidant in the plasma and has the tendency to postoperatively reduced values. This could be caused by an increased antioxidative activity of AA as a radical scavenger since operations are a well-known scenario of oxidative stress with increased radical production. There is some evidence for an intraoperative onset of oxidative stress which could be related to an increased antioxidative activity of AA. Therefore, the total clearance (Cltot) of AA was calculated pre- and intraoperatively in 20 neurosurgical patients. At both times plasma samples were taken before, and 15, 30, 60 and 120 minutes after an iv. AA-bolus of 4 mg/kg AA/body weight. Cltot of AA…
Is At Least One Vitamin Helping Our Vasculature?
2014
See related article, pp 1290–1298 Cardiovascular risk factors such as diabetes mellitus, arterial hypertension, chronic smoking, and hypercholesterolemia are cardiovascular risk factors known to be associated with endothelial dysfunction, a condition that may predict long-term progression of atherosclerosis as well as cardiovascular event rates (for review, see Munzel et al1) Although the mechanisms underlying this phenomenon are complex and multifactorial, there is growing body of evidence that oxidative stress attributable to increased production of reactive oxygen–derived free radicals may play a pivotal role in this process.2 Increased superoxide production by enzyme systems such as the…
Parent-Implemented Hanen Program It Takes Two to Talk®: An Exploratory Study in Spain
2021
Parent-implemented interventions are a highly common approach for enhancing communication and linguistic abilities of late talkers, involving a population that shows a small expressive vocabulary in the absence of other deficits that could explain it. This study aimed to compare the outcomes of a parent-implemented language intervention, It Takes Two to Talk®—The Hanen Program® for Parents (ITTT), to a clinician-directed therapy. Participants were 17 families and their late-talking children: 10 families took part in ITTT and 7 in the clinician-directed modality. The outcomes in the social communication domain were more favorable for the ITTT group, but there were no significant differences …
INTEGRATIVE APPROACH BETWEEN GENE VARIANTS, NEUROENDOCRINE EFFECTORS AND ANXIETY RESPONSE: A PILOT STUDY
2016
The aim of this study is to investigate the neurobiology of stress/emotionality, creating a multidisciplinary assessment model, which can help to provide psychological and physiological responses depending on the genetic background related to sport performances, social closeness and performance anxiety management in team sports. We enrolled 20 female volleyball players aged 13 ± 1 years old played in two different teams during a regional championship final. Saliva collection was carried out before and after the match. In order to evaluate the neuroendocrine effectors involved in stress and performance, we analyzed cortisol and progesterone levels through Elisa standard kit as well as HSP70 …