Showing papers in "Free Radical Biology and Medicine in 2004"

TL;DR: A clear understanding of the mechanisms of action of flavonoids, either as antioxidants or modulators of cell signalling, and the influence of their metabolism on these properties are key to the evaluation of these potent biomolecules as anticancer agents, cardioprotectants, and inhibitors of neurodegeneration.

TL;DR: Future investigations are expected to reveal that a balance between positive and negative factors regulates ARE-mediated gene expression and induction, and a complete mechanism of signal transduction from antioxidants and xenobiotics to the transcription factors, such as Nrf2, that bind to ARE.

TL;DR: The current knowledge regarding potential dietary flavonoid/phenolic-induced toxicity concerns, including their pro-oxidant activity, mitochondrial toxicity (potential apoptosis-inducing properties), and interactions with drug-metabolizing enzymes are summarized.

TL;DR: Observations suggest a hypothesis for the main, ancestral function of uncoupling proteins: to cause mild uncoupled and so diminish mitochondrial superoxide production, hence protecting against disease and oxidative damage at the expense of a small loss of energy.

TL;DR: Observations indicated that the mechanism that modulates Nrf2-Keap1 interaction is pivotal for the cellular sensing mechanism for electrophiles.

TL;DR: The results of kinetic studies and electron turnover experiments suggest that Cd may bind between semiubiquinone and cy tochrome b566 of the Q0 site of cytochrome b of complex III, resulting in accumulation of semiUBiquinones at theQ0 site, providing a possible mechanism for Cd-induced generation of ROS in mitochondria.

TL;DR: This review covers recent advances in metal-induced generation of reactive oxygen species; the receptors, kinases, and nuclear transcription factors affected by metals andMetal-induced oxidative stress; and global cellular phenomena associated with metal- induced ROS production and gene expression.

TL;DR: The results challenge the dogma that nitrate is biologically inert and instead suggest that a complete reverse pathway for generation of NO from nitrate exists.

TL;DR: A reevaluation of the concept of oral bioavailability applied to the dietary flavonoids is presented and the fate of the naturally occurring glycosides, their enzymatic hydrolysis, as well as the resulting aglycones are examined.

TL;DR: The results demonstrate that flavonoids are able to traverse the blood-brain barrier in vivo, however, the permeability of certain flavonoid in vivo is influenced by their lipophilicity and interactions with efflux transporters.

TL;DR: The results suggest that zinc supplementation may lead to down regulation of the inflammatory cytokines through upregulation of the negative feedback loop A20 to inhibit induced NF-kappaB activation.

TL;DR: The mechanisms controlling this activation process as reported in recent studies will be examined and discussed, with particular emphasis on those affecting Nrf2 stability at the molecular level.

TL;DR: In this paper, the metabolism of chlorogenic acid, naringin, and rutin, representative members of three common families of dietary polyphenols, the hydroxycinnamates, the flavanones, and the flavonols, respectively, was studied in an in vitro mixed culture model of the human colonic microflora.

TL;DR: Intervention to increase the paraoxonases (cellular and humoral) by dietary or pharmacological means can reduce macrophage foam cell formation and attenuate atherosclerosis development.

TL;DR: Green tea catechin polyphenols, formerly thought to be simple radical scavengers, are now considered to invoke a spectrum of cellular mechanisms of action related to their neuroprotective activity, including pharmacological activities like iron chelation, scavenging of radicals, activation of survival genes and cell signaling pathways, and regulation of mitochondrial function and possibly of the ubiquitin-proteasome system.

TL;DR: This review summarizes the evidence that implicates ROS as key regulators of MMP production and the importance of these interactions in disease pathologies.

TL;DR: In vitro and in vivo production of 4HNE in response to pro-oxidant exposure has been demonstrated using antibodies to protein adducts of the lipid aldehyde, suggesting a role for protein modification by 4H NE in the pathogenesis of several diseases.

TL;DR: It is concluded that much, if not all, of the pro-oxidant activity of aluminum might be explained by the formation of an aluminum superoxide semireduced radical ion.

TL;DR: The present article systematically review the hitherto published evidence that promoter polymorphisms in the HO-1 gene exert functional importance by influencing the level ofHO-1 expression in different organ systems to suggest an important endogenous protective factor.

TL;DR: The newly described role of hemoglobin as a nitrite reductase is discussed in the context of blood flow regulation, oxygen sensing, and nitrite-based therapeutics.

TL;DR: This concept suggests that for many types of tumors antioxidants could be used to diminish the invasive capability of malignant cells.

TL;DR: A new concept is presented that cyt c actuates both of these oxidative roles through a uniform mechanism: its specific interactions with each of these phospholipids result in the conversion and activation of cyt c, transforming it from an innocuous electron transporter into a calamitous peroxidase capable of oxidizing the activating phospholIPids.

TL;DR: It is shown that a tris-malonic acid derivative of the fullerene C3 is capable of removing the biologically important superoxide radical with a rate constant, approximately 100-fold slower than the superoxide dismutases (SOD), a family of enzymes responsible for endogenous dismutation of superoxide.

TL;DR: Cognitive aging should be slowed, and possibly even reversed, by appropriately increasing levels of antioxidants or decreasing overproduction of free radicals in the body.

TL;DR: This review focuses on the emerging role of oxidative stress and mitochondrial dysfunction both as a consequence and as a cause of epileptic seizures.

TL;DR: This interpretation is supported by a strong linear correlation between the magnitude of the blood pressure effect caused by infusion of cross-linked recombinant hemoglobin tetramers in vivo and the rate of NO dioxygenation by these proteins measured in vitro.

TL;DR: A nascent body of epidemiological data suggests that gamma-tocopherol is a better negative risk factor for certain types of cancer and myocardial infarction than is a alpha-tocypes, and argues for thorough experimental and epidemiological reappraisal of desmethyl tocopherols, especially within the contexts of cardiovascular disease and cancer biology.

TL;DR: Recent studies from the laboratories strongly suggest that HNE is a key signaling molecule and that GSTs, being determinants of its intracellular concentrations, can regulate stress-mediated signaling.

TL;DR: Cocoa polyphenols may increase the concentration of HDL cholesterol, whereas chocolate fatty acids may modify the fatty acid composition of LDL and make it more resistant to oxidative damage.

TL;DR: Markers of inflammation were increased dramatically in response to the run regardless of treatment group and AO supplementation prevented endurance exercise-induced lipid peroxidation but had no effect on inflammatory markers.