Search results for "ANTIOXIDANTS"
showing 10 items of 827 documents
Comparative analysis of stress responses of H9c2 rat cardiomyoblasts following treatment with doxorubicin and tBOOH
2011
Abstract Cardiotoxicity is the major dose-limiting adverse effect of anthracyclines and is hypothesized to result from damage induced by reactive oxygen species (ROS) or inhibition of topoisomerase II. Here, we comparatively analyzed the effect of doxorubicin and the organic peroxide tertiary-butylhydroperoxide (tBOOH) on stress responses of rat cardiomyblast cells (H9c2). Moreover, we investigated the impact of serum factors and the novel prototypical protein kinase CK2 inhibitor resorufin on the sensentivity of H9c2 cells exposed to doxorubicin or tBOOH. Measuring cell viability by use of the WST assay as well as cell cycle progression and apoptotic death by FACS-based methods, we found t…
Prevention of 7-ketocholesterol-induced side effects by natural compounds
2018
Cholesterol oxidation products, also named oxysterols, can be formed either by cholesterol auto-oxidation, enzymatically or both. Among these oxysterols, 7-ketocholesterol (7KC) is mainly formed during radical attacks that take place on the carbon 7 of cholesterol. As increased levels of 7KC have been found in the tissues, plasma and/or cerebrospinal fluid of patients with major diseases, especially age-related diseases (cardiovascular diseases, eye diseases, neurodegenerative diseases), some cancers, and chronic inflammatory diseases, it is suspected that 7KC, could contribute to their development. Since 7KC, provided by the diet or endogenously formed, is not or little efficiently metabol…
The Recent Crystal Structure of Human Tyrosinase Related Protein 1 (HsTYRP1) Solves an Old Problem and Poses a New One
2017
Show your metal: l-Tyrosine is converted into the protective antioxidative polymer melanin in a sequence of reactions. In humans, the catalytic pathway starts with the tyrosinase HsTYR and two tyrosinase-related proteins HsTYRP1 and HsTYRP2. All three enzymes have the same active site but the latter two contain two zinc ions instead of copper ions.
Increased oxidative stress and impaired antioxidant response in Lafora disease.
2014
15 páginas, 10 figuras
Piclamilast inhibits the pro-apoptotic and anti-proliferative responses of A549 cells exposed to H(2)O(2) via mechanisms involving AP-1 activation.
2012
Reactive oxygen species (ROS) are involved in the pathogenesis of many inflammatory diseases such as chronic obstructive pulmonary disease (COPD). They can alter the expression of genes involved in cellular damage by activating transcription factors, including the NF-κB and the activator protein 1 (AP-1). Phosphodiesterase type 4 (PDE4) inhibitors have anti-inflammatory and antioxidant effects, as described in in vivo and in vitro COPD models. This study analysed the effects of piclamilast, a selective PDE4 inhibitor, on modulating the global gene expression profile in A549 cells exposed to H(2)O(2).Changes in gene expression were analysed using high-density Affymetrix microarrays and valid…
Antioxidant Bibenzyl Derivatives from Notholaena nivea Desv.
2011
Four new bibenzyl derivatives were isolated, together with other known bibenzyls, by bioassay-guided fractionation of a CHCl3-MeOH extract of Notholaena nivea Desv. (Pteridaceae) aerial parts. The structures were elucidated by NMR, ESIMS and other spectral analyses. Their antioxidative effects towards superoxide, lipidic peroxidation and the 2,2'- azino-bis-3- ethilbenzothiazoline-6-sulfonic acid (ABTS) radical were assayed. Results showed that the compound 3,12-dihydroxy-5-methoxybibenzyl (6) is the most active compound in the ABTS free-radical scavenging test, while in the coupled oxidation of ȕ-carotene and linoleic acid assay the compound 5,12-dihydroxy-3-methoxydibenzyl-6- carboxylic a…
Aza- and Azo-Stilbenes: Bio-Isosteric Analogs of Resveratrol
2020
Several series of natural polyphenols are described for their biological and therapeutic potential. Natural stilbenoid polyphenols, such as trans-resveratrol, pterostilbene and piceatannol are well-known for their numerous biological activities. However, their moderate bio-availabilities, especially for trans-resveratrol, prompted numerous research groups to investigate innovative and relevant synthetic resveratrol derivatives. This review is focused on isosteric resveratrol analogs aza-stilbenes and azo-stilbenes in which the C=C bond between both aromatic rings was replaced with C=N or N=N bonds, respectively. In each series, synthetic ways will be displayed, and structural sights will be…
Oxidative Stress and Respiratory System: Pharmacological and Clinical Reappraisal of N-Acetylcysteine
2014
Abstract The large surface area for gas exchange makes the respiratory system particularly susceptible to oxidative stress-mediated injury. Both endogenous and exogenous pro-oxidants (e.g. cigarette smoke) trigger activation of leukocytes and host defenses. These mechanisms interact in a ìmultilevel cycleî responsible for the control of the oxidant/antioxidant homeostasis. Several studies have demonstrated the presence of increased oxidative stress and decreased antioxidants (e.g. reduced glutathione [GSH]) in subjects with chronic obstructive pulmonary disease (COPD), but the contribution of oxidative stress to the pathophysiology of COPD is generally only minimally discussed. The aim of t…
Future Directions in the Pharmacologic Therapy of Chronic Obstructive Pulmonary Disease
2005
Current therapy for chronic obstructive pulmonary disease (COPD) fails to alter its relentless progression. This remains a significant challenge and unmet need. A recent advance is the demonstration that treatment with a fixed dose of an inhaled corticosteroid and a long-acting beta2-agonist in COPD improves lung function and quality of life, and reduces exacerbation more effectively than either drug alone. Other improvements include the introduction of tiotropium, a once-daily anticholinergic. In advanced clinical development are other once-daily bronchodilators and combinations of anticholinergic drugs and beta2-agonists. Increased understanding of the pathogenesis of COPD has led to nove…
Antioxidants: Role in the prevention and treatment of bronchopulmonary dysplasia
2022
Bronchopulmonary dysplasia (BPD) is one of the major causes of chronic respiratory diseases among infants. Both pharmacological and nonpharmacological approaches have been proposed for its management. Since oxidative stress is known to play a pivotal role in the pathogenesis of BPD, it is reasonable to consider the potential of antioxidant strategies in the prevention and treatment of this condition. Indeed, antioxidants can prevent or inhibit substrate oxidation. Some studies have evaluated the efficacy of the exogenous administration of vitamins and micronutrients in reducing the propagation of free radicals through their scavenging capacity. Nonetheless, encouraging preclinical results d…