Regulation of antioxidant enzymes: a significant role for melatonin

Journal of Pineal Research, Journal Year: 2003, Volume and Issue: 36(1), P. 1 - 9

Published: Dec. 11, 2003

Abstract: Antioxidant enzymes form the first line of defense against free radicals in organisms. Their regulation depends mainly on oxidant status cell, given that oxidants are their principal modulators. However, other factors have been reported to increase antioxidant enzyme activity and/or gene expression. During last decade, melatonin has shown possess genomic actions, regulating expression several genes. Melatonin also influences both and cellular mRNA levels for these enzymes. In present report, we review studies which document influence antioxidative glutathione peroxidase, superoxide dismutases catalase under physiological conditions elevated oxidative stress. We analyze possible mechanisms by regulates

Language: Английский

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Oxidative stress impairs oocyte quality and melatonin protects oocytes from free radical damage and improves fertilization rate

Journal of Pineal Research, Journal Year: 2007, Volume and Issue: 44(3), P. 280 - 287

Published: Oct. 29, 2007

We investigated the relationship between oxidative stress and poor oocyte quality whether antioxidant melatonin improves quality. Follicular fluid was sampled at retrieval during in vitro fertilization embryo transfer (IVF-ET). Intrafollicular concentrations of 8-hydroxy-2'-deoxyguanosine (8-OHdG) women with high rates degenerate oocytes were significantly higher than those low oocytes. As there a negative correlation intrafollicular 8-OHdG melatonin, 18 patients undergoing IVF-ET given (3 mg/day), vitamin E (600 mg/day) or both E. hexanoyl-lysine adduct reduced by these treatments. One hundred fifteen who failed to become pregnant rate (< =50%) previous cycle divided into two groups next procedure; 56 treatment 59 without treatment. The improved compared cycle. However, not changed Oocytes recovered from preovulatory follicles mice incubated H2O2 for 12 hr. percentage mature first polar body addition (300 microm). inhibitory effect blocked simultaneous melatonin. In conclusion, causes toxic effects on maturation protects stress. Melatonin is likely improve rates.

Language: Английский

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Reducing oxidative/nitrosative stress: a newly-discovered genre for melatonin

Critical Reviews in Biochemistry and Molecular Biology, Journal Year: 2009, Volume and Issue: 44(4), P. 175 - 200

Published: July 6, 2009

The discovery of melatonin and its derivatives as antioxidants has stimulated a very large number studies which have, virtually uniformly, documented the ability these molecules to detoxify harmful reactants reduce molecular damage. These observations have clear clinical implications given that numerous age-related diseases in humans an important free radical component. Moreover, major theory explain processes aging invokes radicals their causative agents. conditions, coupled with loss organisms age, suggest some aspects may be aggravated by diminished levels advanced age. Another corollary this is administration melatonin, uncommonly low toxicity profile, could theoretically defer progression possibly forestall signs aging. Certainly, research next decade will help define role determining successful While increasing life span not necessarily goal investigative efforts, improving health quality aged should aim research.

Language: Английский

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Melatonin and the ovary: physiological and pathophysiological implications

Fertility and Sterility, Journal Year: 2008, Volume and Issue: 92(1), P. 328 - 343

Published: Sept. 19, 2008

Language: Английский

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Circadian Rhythm Connections to Oxidative Stress: Implications for Human Health

Antioxidants and Redox Signaling, Journal Year: 2012, Volume and Issue: 19(2), P. 192 - 208

Published: Dec. 2, 2012

Significance: Oxygen and circadian rhythmicity are essential in a myriad of physiological processes to maintain homeostasis, from blood pressure sleep/wake cycles, down cellular signaling pathways that play critical roles health disease. If the human body or cells experience significant stress, their ability regulate internal systems, including redox levels rhythms, may become impaired. At as well organismal levels, impairment regulation rhythms lead number adverse effects, manifestation variety diseases such heart diseases, neurodegenerative conditions, cancer. Recent Advances: Researchers have come an understanding basics rhythm mechanism, importance numerous species oxidative stress components. The effects dysregulated been subject intense investigations since they were first discovered, recent into molecular mechanisms linking two started elucidate bases connection. Critical Issues: While much is known about mechanics systems front where interact has had very little research focused on it. This review discusses idea these together intricately involved healthy body, Future Directions: We believe for more efficacious management both components pathogenesis, targeting tandem would be far successful. Antioxid. Redox Signal. 19, 192–208

Language: Английский

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Circadian Rhythms, Oxidative Stress, and Antioxidative Defense Mechanisms

Chronobiology International, Journal Year: 2003, Volume and Issue: 20(6), P. 921 - 962

Published: Jan. 1, 2003

Endogenous circadian and exogenously driven daily rhythms of antioxidative enzyme activities low molecular weight antioxidants (LMWAs) are described in various phylogenetically distant organisms. Substantial amplitudes detected several cases, suggesting the significance rhythmicity avoiding excessive oxidative stress. Mammalian and/or avian glutathione peroxidase and, as a consequence, reductase follow rhythm melatonin. Another hint for an involvement melatonin control redox processes is seen its high‐affinity binding to cytosolic quinone 2, previously believed be receptor. Although protection by pharmacological doses repeatedly reported, explanations these findings still insufficient their physiological chronobiological relevance not yet settled. Recent data indicate role avoidance mitochondrial radical formation, function which may prevail over direct scavenging. Rhythmic changes damage protein lipid molecules also reported. Enhanced modification accompanied marked increase amplitude this parameter Drosophila mutant rosy, deficient LMWA urate. Preliminary evidence diminishing stress comes from clock mutants. In Drosophila, moderately enhanced arrhythmic null per0, but even more elevated, periodic found short‐period pers, synchronized LD 12:12. Remarkably large increases damage, along with impairment tissue integrity and—obviously insufficient—compensatory elevations protective enzymes observed particularly vulnerable organ, Harderian gland, another tau, Syrian hamster. Mice per2 gene homolog reported cancer‐prone, finding might relate dinoflagellate Lingulodinium polyedrum [Gonyaulax polyedra], treatments that cause result strong suppressions metabolite 5‐methoxytryptamine (5‐MT) secondary effects on overt rhythmicity. The glow maximum, depending presence elevated 5‐MT at end subjective night, decreases dose‐dependent manner already under moderate, non‐lethal stress, restored replenishing Therefore, general effect consist declines easily oxidizable signaling such melatonin, can have consequences intraorganismal organization expression rhythms. redox‐sensitive input into core oscillator via modulation NPAS2/BMAL1 or CLK/BMAL1 heterodimer DNA influence cellular balance, including clock.

Language: Английский

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Melatonin in higher plants: occurrence and possible functions

Journal of Pineal Research, Journal Year: 2005, Volume and Issue: 39(4), P. 333 - 341

Published: Sept. 12, 2005

Abstract: Melatonin may be ubiquitous in the plant kingdom. This review considers evaluation of methods melatonin determination material and possible functions plants. Concerning methods, only reliable techniques are liquid chromatography – mass spectrometry or gas after some purification steps extract. was shown to delay flower induction photoperiodic plants dinoflagellate Lingulodinium it replaces, part, requirement darkness for cyst formation. also have a function as an antioxidant possess auxin‐like effects. Finally, act signal interaction with herbivores pests. Further research is needed clarify these potential functions.

Language: Английский

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The circadian clock within the heart: potential influence on myocardial gene expression, metabolism, and function

AJP Heart and Circulatory Physiology, Journal Year: 2005, Volume and Issue: 290(1), P. H1 - H16

Published: Dec. 22, 2005

It is becoming increasingly clear that the intrinsic properties of both heart and vasculature exhibit dramatic oscillations over course day. Diurnal variations in responsiveness cardiovascular system to environmental stimuli are mediated by a complex interplay between extracellular (i.e., neurohumoral factors) intracellular circadian clock) influences. The clock composed series transcriptional modulators together allow cell perceive time day, thereby enabling preparation for an anticipated stimulus. These molecular timepieces have been characterized recently within vascular smooth muscle cells cardiomyocytes, giving rise multitude hypotheses relating potential role(s) as modulator physiological pathophysiological events. For example, evidence strongly supports hypothesis modulates myocardial metabolism, which turn facilitates anticipation diurnal workload, substrate availability, and/or energy supply-to-demand ratio. purpose this review therefore summarize our current understanding events governing heart, with special emphasis on intramyocardial clock. Whether impairment mechanism contributes toward disease associated hypertension, diabetes mellitus, shift work, sleep apnea, obesity will be discussed.

Language: Английский

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Oxidative Stress in Endurance Flight: An Unconsidered Factor in Bird Migration

PLoS ONE, Journal Year: 2014, Volume and Issue: 9(5), P. e97650 - e97650

Published: May 15, 2014

Migrating birds perform extraordinary endurance flights, up to 200 h non-stop, at a very high metabolic rate and while fasting. Such an intense prolonged physical activity is normally associated with increased production of reactive oxygen nitrogen species (RONS) thus risk oxidative stress. However, now it was unknown whether flight evokes We measured marker damage (protein carbonyls, PCs) enzymatic antioxidant capacity (glutathione peroxidase, GPx) in the European robin (Erithacus rubecula), nocturnal migrant, on its way non-breeding grounds. Both markers were significantly higher robins caught out their than conspecifics during day resting. Independently time day, both showed concentrations individuals reduced muscles. Adults had GPx first-year first migration. These results show for that free-flying migrants experience stress up-regulate one component capacity. discuss avoiding may be overlooked factor shaping bird migration strategies, e.g. by disfavouring long non-stop flights extensive catabolism

Language: Английский

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Melatonin reduces glial reactivity in the hippocampus, cortex, and cerebellum of streptozotocin-induced diabetic rats

Free Radical Biology and Medicine, Journal Year: 2003, Volume and Issue: 35(7), P. 797 - 804

Published: Oct. 1, 2003

Language: Английский

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