Search results for "Reactive"
showing 10 items of 1469 documents
Antifungal drugs influence neutrophil effector functions
2019
There is a growing body of evidence for immunomodulatory side effects of antifungal agents on different immune cells, e.g., T cells. Therefore, the aim of our study was to clarify these interactions with regard to the effector functions of polymorphonuclear neutrophils (PMN). Human PMN were preincubated with fluconazole (FLC), voriconazole (VRC), posaconazole (POS), isavuconazole (ISA), caspofungin (CAS), micafungin (MFG), conventional amphotericin B (AMB), and liposomal amphotericin B (LAMB). PMN then were analyzed by flow cytometry for activation, degranulation, and phagocytosis and by dichlorofluorescein assay to detect reactive oxygen species (ROS). Additionally, interleukin-8 (IL-8) re…
Effects of Ultrasound-Assisted Extraction and Solvent on the Phenolic Profile, Bacterial Growth, and Anti-Inflammatory/Antioxidant Activities of Medi…
2020
© 2020 by the authors.
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…
Drugs modulating the biological effects of peroxynitrite and related nitrogen species.
2007
The term “reactive nitrogen species” includes nitrogen monoxide, commonly called nitric oxide, and some other remarkable chemical entities (peroxynitrite, nitrosoperoxycarbonate, etc.) formed mostly from nitrogen monoxide itself in biological environments. Regardless of the specific mechanisms implicated in their effects, however, it is clear that an integrated pharmacological approach to peroxynitrite and related species is only just beginning to take shape. The array of affected chemical and pathological processes is extremely broad. One of the most conspicuous mechanisms observed thus far has been the scavenging of the peroxynitrite anion by molecules endowed with antioxidant activity. T…
Tiliroside and gnaphaliin inhibit human low density lipoprotein oxidation.
2004
Two flavonoids, gnaphaliin and tiliroside, isolated from Helichrysum italicum, were studied in vitro for their capacity to inhibit Cu(2+)-induced human low density lipoprotein (LDL) and diluted plasma oxidation. LDL oxidation was monitored by conjugated diene, thiobarbituric acid-reactive substances (TBARS) formation and electrophoretic mobility on agarose gel. Gnaphaliin and tiliroside increased the lag-phase for diene conjugate production in a dose-dependent manner. The reduction of TBARS production confirmed the antioxidant activity of gnaphaliin and tiliroside with 50% inhibitory concentration (IC(50)) values of 8.0+/-3.9 microM and 7.0+/-2.6 microM respectively. Furthermore, the flavon…
Molecular mechanisms of the cardiovascular protective effects of polyphenols
2012
Epidemiological studies have reported a greater reduction in cardiovascular risk and metabolic disorders associated with diets rich in polyphenols. The antioxidant effects of polyphenols are attributed to the regulation of redox enzymes by reducing reactive oxygen species production from mitochondria, NADPH oxidases and uncoupled endothelial NO synthase in addition to also up-regulating multiple antioxidant enzymes. Although data supporting the effects of polyphenols in reducing oxidative stress are promising, several studies have suggested additional mechanisms in the health benefits of polyphenols. Polyphenols from red wine increase endothelial NO production leading to endothelium-depende…
Moderate exercise is an antioxidant: Upregulation of antioxidant genes by training
2006
Exercise causes oxidative stress only when exhaustive. Strenuous exercise causes oxidation of glutathione, release of cytosolic enzymes, and other signs of cell damage. However, there is increasing evidence that reactive oxygen species (ROS) not only are toxic but also play an important role in cell signaling and in the regulation of gene expression. Xanthine oxidase is involved in the generation of superoxide associated with exhaustive exercise. Allopurinol (an inhibitor of this enzyme) prevents muscle damage after exhaustive exercise, but also modifies cell signaling pathways associated with both moderate and exhaustive exercise in rats and humans. In gastrocnemius muscle from rats, exerc…
Free radical biology of the cardiovascular system
2012
Most cardiovascular diseases (CVDs), as well as age-related cardiovascular alterations, are accompanied by increases in oxidative stress, usually due to increased generation and/or decreased metabolism of ROS (reactive oxygen species; for example superoxide radicals) and RNS (reactive nitrogen species; for example peroxynitrite). The superoxide anion is generated by several enzymatic reactions, including a variety of NADPH oxidases and uncoupled eNOS (endothelial NO synthase). To relieve the burden caused by this generation of free radicals, which also occurs as part of normal physiological processes, such as mitochondrial respiratory chain activity, mammalian systems have developed endogen…