Search results for " STRESS"
showing 10 items of 3936 documents
Potential therapeutic effects of natural heme oxygenase-1 inducers in cardiovascular diseases.
2013
Significance: Many physiological effects of natural antioxidants, their extracts or their major active components, have been reported in recent decades. Most of these compounds are characterized by a phenolic structure, similar to that of α-tocopherol, and present antioxidant properties that have been demonstrated both in vitro and in vivo. Polyphenols may increase the capacity of endogenous antioxidant defenses and modulate the cellular redox state. Such effects may have wide-ranging consequences for cellular growth and differentiation. Critical Issues: The majority of in vitro and in vivo studies conducted so far have attributed the protective effect of bioactive polyphenols to their chem…
Regression Modeling of the Antioxidant-to-Nephroprotective Relation Shows the Pivotal Role of Oxidative Stress in Cisplatin Nephrotoxicity
2021
The clinical utility of the chemotherapeutic drug cisplatin is significantly limited by its nephrotoxicity, which is characterized by electrolytic disorders, glomerular filtration rate decline, and azotemia. These alterations are consequences of a primary tubulopathy causing injury to proximal and distal epithelial cells, and thus tubular dysfunction. Oxidative stress plays a role in cisplatin nephrotoxicity and cytotoxicity, but its relative contribution to overall toxicity remains unknown. We studied the relation between the degree of oxidative reduction (provided by antioxidant treatment) and the extent of nephrotoxicity amelioration (i.e., nephroprotection) by means of a regression anal…
Delivery of liquorice extract by liposomes and hyalurosomes to protect the skin against oxidative stress injuries.
2015
Liquorice extract, obtained by percolation in ethanol of Glycyrrhiza glabra L. roots, was incorporated in liposomes and hyalurosomes, new phospholipid-sodium hyaluronate vesicles, and their protective effect against oxidative stress skin damages was probed. As a comparison, raw glycyrrhizin was also tested. All the vesicles were small in size (≤ 100 nm), with a highly negative zeta potential ensuring long-term stability, and able to incorporate a high amount of the extract. In vitro tests showed that the liquorice extract loaded in vesicles was able to scavenge DPPH free radical (80% inhibition) and to protect 3T3 fibroblasts against H2O2-induced oxidative stress, restoring the normal condi…
Increased Stress Resistance and Lifespan in Chaenorhabditis elegans Wildtype and Knockout Mutants—Implications for Depression Treatment by Medicinal …
2021
Depression and anxiety disorders are widespread diseases, and they belong to the leading causes of disability and greatest burdens on healthcare systems worldwide. It is expected that the numbers will dramatically rise during the COVID-19 pandemic. Established medications are not sufficient to adequately treat depression and are not available for everyone. Plants from traditional medicine may be promising alternatives to treat depressive symptoms. The model organism Chaenorhabditis elegans was used to assess the stress reducing effects of methanol/dichlormethane extracts from plants used in traditional medicine. After initial screening for antioxidant activity, nine extracts were selected f…
Antioxidant activity of 5-FU and new fluorinated uracil derivates
2017
The intake of antioxidants has increased in the last years in order to treat some pathologies associated with oxidative stress such as cancer, diabetes mellitus, atherosclerosis, myocardial infarction, acute pancreatitis, Parkinson's and Alzheimer's disease among others. In colorectal cancer, a widely antineoplastic drug used is the fluorinated uracil molecule 5-Fluorouracile (5-FU). The aim of this study is to assess the antioxidant capacity observed by the inhibition of lipid peroxidation by 5-FU and other fluorinated uracil derivates: 6-[Difluoro(phenyl)methyl]-3-(2,4,6-trifluorophenyl)pyrimidine-2,4(1H,3H)-dione (S-81), 3-[2-Chloroethyl]-6-[difluoro(phenyl)methyl]pyrimidine-2,4(1H,3H)-d…
Use of Saccharomyces cerevisiae and Caenorhabditis elegans as model organisms to study the effect of cocoa polyphenols in the resistance to oxidative…
2011
Developing functional foods to improve the quality of life for elderly people has great economic and social impact. Searching for and validating ingredients with in vivo antioxidant effects is one of the key steps in developing this kind of food. Here we describe the combined use of simple biological models and transcriptomics to define the functional intracellular molecular targets of a polyphenol-enriched cocoa powder. Cocoa powder supplemented culture medium led to increased resistance to oxidative stress, in both the budding yeast Saccharomyces cerevisiae and the nematode Caenorhabditis elegans, and, in the latter, lifespan was also increased. These effects are fully dependent on the po…
Oxidative stress protection by manganese complexes of tail-tied aza-scorpiand ligands.
2015
The Mn2+ coordination chemistry of double scorpiand ligands in which two polyazacyclophane macrocycles have been connected by pyridine, phenanthroline and bipyridine spacers has been studied by potentiometry, paramagnetic NMR and electrochemistry. All ligands show high stability with Mn2+ and the complexes were formed in a wide pH range. DFT calculations support the structures and coordination geometries derived from the study. A remarkable antioxidant activity was evidenced for these systems by the McCord-Fridovich assay and in Escherichiacoli sodAsodB deficient bacterial cells. The three systems were tested as anti-inflammatory drugs in human macrophages measuring the accumulation of cyto…
Organic Nitrates and Nitrate Tolerance—State of the Art and Future Developments
2010
The hemodynamic and antiischemic effects of nitroglycerin (GTN) are lost upon chronic administration due to the rapid development of nitrate tolerance. The mechanism of this phenomenon has puzzled several generations of scientists, but recent findings have led to novel hypotheses. The formation of reactive oxygen and nitrogen species in the mitochondria and the subsequent inhibition of the nitrate-bioactivating enzyme mitochondrial aldehyde dehydrogenase (ALDH-2) appear to play a central role, at least for GTN, that is, bioactivated by ALDH-2. Importantly, these findings provide the opportunity to reconcile the two “traditional” hypotheses of nitrate tolerance, that is, the one postulating …
Extraction of polyphenols in Himanthalia elongata and determination by high performance liquid chromatography with diode array detector prior to its …
2016
Abstract Several studies have demonstrated the antioxidant capacity of seaweeds, which can be used for the development of biopharmaceuticals with extensive medical application. Antioxidant therapies appear to attenuate the organic deterioration originated by an excessive oxidative stress, which could prevent the harmful effects of various injuries such as ischemia-reperfusion (I/R) among others. Marine brown seaweeds play a significant role, as they are the only organisms on earth producing phlorotannins, which are polyphenols that exhibit important biological activity. To ensure obtaining an extract with the greatest antioxidant activity, some variables that affect the extraction of polyph…
Antioxidant Properties of a Supercritical Fluid Extract of the Halophyte Mesembryanthemum nodiflorum L. from Sicilian Coasts: Nutraceutical and Cosme…
2020
The aim of this paper was to obtain different extracts from the aerial parts of Mesembryanthemum nodiflorum, comparing traditional extraction (using solvents with increasing polarity such as hexane, ethanol 80%, acetone 70% and water) with an eco-friendly technique (supercritical fluid extraction (SFE))