Search results for " STRESS"
showing 10 items of 3936 documents
4-dimethylamino-3′,4′-dimethoxychalcone downregulates iNOS expression and exerts anti-inflammatory effects
2001
Abstract Reactive oxygen and nitrogen species contribute to the pathophysiology of inflammatory conditions. We have studied the effects of a novel superoxide scavenger, 4-dimethylamino-3′,4′-dimethoxychalcone (CH11) in macrophages and in vivo. CH11 has been shown to inhibit the chemiluminescence induced by zymosan in mouse peritoneal macrophages and the cytotoxic effects of superoxide. In the same cells, the modulation by superoxide of nitric oxide (NO) production in response to zymosan was investigated. CH11 was more effective than the membrane-permeable scavenger Tiron for inhibition of inducible nitric oxide synthase (iNOS) protein expression and nitrite production. We have shown that CH…
Disruption of the Candida albicans ATC1 gene encoding a cell-linked acid trehalase decreases hypha formation and infectivity without affecting resist…
2007
In Candida albicans, the ATC1 gene, encoding a cell wall-associated acid trehalase, has been considered as a potentially interesting target in the search for new antifungal compounds. A phenotypic characterization of the double disruptant atc1Delta/atc1Delta mutant showed that it was unable to grow on exogenous trehalose as sole carbon source. Unlike actively growing cells from the parental strain (CAI4), the atc1Delta null mutant displayed higher resistance to environmental insults, such as heat shock (42 degrees C) or saline exposure (0.5 M NaCl), and to both mild and severe oxidative stress (5 and 50 mM H(2)O(2)), which are relevant during in vivo infections. Parallel measurements of int…
Oxidative burst and neutrophil elastase contribute to clearance of Aspergillus fumigatus pneumonia in mice.
2014
Polymorphonuclear neutrophils (PMN) are important for the control of invasive aspergillosis (IA), a major threat to immunocompromised individuals. For clearance of Aspergillus fumigatus infections, PMN employ their potent oxidative and non-oxidative mechanisms. To clarify the relative contribution of these mechanisms, we analyzed p47(phox-/-), gp91(phox-/-) and elastase (ELA) deficient mice (ELANE) after intratracheal infection with A. fumigatus. Infected p47(phox-/-) and gp91(phox-/-) mice died within 4 days and had a significant higher fungal burden in the lungs compared to wild-type controls. Interestingly, the survival of ELANE mice after infection was unimpaired suggesting that ELA is …
Farmed Gilthead Sea Bream (Sparus aurata) by-Products Valorization: Viscera Oil ω-3 Enrichment by Short-Path Distillation and In Vitro Bioactivity Ev…
2021
This study shows a pilot scale protocol aimed to obtain an omega 3-enriched oil after the processing of farmed gilthead sea bream viscera (SBV)
Antioxidant Pathways in Alzheimers Disease: Possibilities of Intervention
2011
Alzheimer's disease (AD) is closely related to the occurrence of oxidative stress. It was claimed that all pathophysiological mechanisms involved in the onset and progression of AD are related to oxidative stress. Thus, it is important to evaluate if there is oxidative stress as well as the mechanism by which this happens in AD patients as well as in animal models of AD. Extracellular plaques of amyloid b peptides (Aβ), a hallmark of the disease, have been postulated to be more protective than damaging in terms of oxidative stress because they may be chemical sinks in which heavy metals are placed. More than a decade ago we reasoned that damage due to Ab might be caused not by extracellular…
Oxidative stress of alternariol in Caco-2 cells
2014
Alternariol (AOH) is a mycotoxin produced by fungus Alternaria. It is found in a wide variety of fruits and cereals products. AOH is able to damage human health. The aim of this study was to evaluate the cytotoxicity of AOH in human colon adenocarcinoma (Caco-2) cells. Moreover, some events related to oxidative stress were evaluated: reactive oxygen species (ROS) generated by oxidation of 2',7'-dichlorodihydrofluorescein diacetate; peroxidation of lipid (LPO) by malondialdehyde (MDA) production; and antioxidant enzymatic capability of catalase (CAT) and superoxide dismutase (SOD). Cytotoxicity of AOH (from 3.125 to 100 μM) was determined during 24, 48 and 72 h of exposure by different endpo…
Evaluation of the antioxidant capacity, furan compounds and cytoprotective/cytotoxic effects upon Caco-2 cells of commercial Colombian coffee.
2017
Abstract Antioxidant capacity (AC), total phenolics (TPs), furan compounds (HMF and furfural F) and cytoprotective/cytotoxic effects upon Caco-2 cells (MTT, cell cycle and reactive oxygen species (ROS)) were evaluated in Colombian coffee (2 ground and 4 soluble samples). The AC (ABTS and FRAP), TPs and HMF ranged between 124–722, 95–802 μmoles Trolox/g, 21–100 mg gallic acid/g and 69–2900 mg/kg, respectively. Pretreatment of cells for 24 h with lyophilized coffee infusions at the highest dose without cytotoxic effects (500 μg/mL) significantly prevented the decrease in cell viability compared to control stress with H2O2 (5 mM/2 h), recovering viability to values between 34% and 45% and rest…
Antioxidant effect derived from bioaccessible fractions of fruit beverages against H2O2-induced oxidative stress in Caco-2 cells
2008
Abstract This work evaluates the effect of bioaccessible fractions from fruit beverages against oxidative stress (OS) in Caco-2 cells. A fruit beverage (grape + orange + apricot) (with/without milk and/or iron/zinc) was subjected to in vitro gastrointestinal digestion, and bioaccessible fractions were incubated with Caco-2 cell cultures. Following preincubation, OS was induced with 5 mM H 2 O 2 . Intracellular reactive oxygen species (ROS), mitochondrial potential (Δ ψ m ), mitochondrial metabolism (MTT test), intracellular reduced glutathione (GSH) and superoxide dismutase activity (SOD) were measured. The data evidenced viable cultures with increased mitochondrial metabolism and GSH-Rd ac…
Oxidative stress and DNA damage in agricultural workers after exposure to pesticides
2021
Abstract Background Recent epidemiological studies on workers describe that exposure to pesticides can induce oxidative stress by increased production of free radicals that can accumulate in the cell and damage biological macromolecules, for example, RNA, DNA, DNA repair proteins and other proteins and/or modify antioxidant defense mechanisms, as well as detoxification and scavenger enzymes. This study aimed to assess oxidative stress and DNA damage among workers exposed to pesticides. Methods For this purpose, 52 pesticide exposed workers and 52 organic farmers were enrolled. They were assessed: the pesticide exposure, thiobarbituric acid reactive substances (TBARS), total glutathione (TG)…
Antioxidant Bioactivity of Extracts from Beach Cast Leaves of Posidonia oceanica (L.) Delile
2021
The marine environment is a generous source of biologically active compounds useful for human health. In 50 years, about 25,000 bioactive marine compounds have been identified, with an increase of 5% per year. Peculiar feature of algae and plants is the production of secondary metabolites, such as polyphenols, synthesized as a form of adaptation to environmental stress. Posidonia oceanica is a Mediterranean endemic and dominant seagrass and represents a biologically, ecologically and geologically important marine ecosystem. Within this study, methanolic and ethanolic extracts were generated from fresh and dried Posidonia