Melatonin as an antioxidant: under promises but over delivers

Journal of Pineal Research, Год журнала: 2016, Номер 61(3), С. 253 - 278

Опубликована: Авг. 8, 2016

Melatonin is uncommonly effective in reducing oxidative stress under a remarkably large number of circumstances. It achieves this action via variety means: direct detoxification reactive oxygen and nitrogen species indirectly by stimulating antioxidant enzymes while suppressing the activity pro-oxidant enzymes. In addition to these well-described actions, melatonin also reportedly chelates transition metals, which are involved Fenton/Haber-Weiss reactions; doing so, reduces formation devastatingly toxic hydroxyl radical resulting reduction stress. Melatonin's ubiquitous but unequal intracellular distribution, including its high concentrations mitochondria, likely aid capacity resist cellular apoptosis. There credible evidence suggest that should be classified as mitochondria-targeted antioxidant. prevent damage associated physiological debilitation well documented numerous experimental ischemia/reperfusion (hypoxia/reoxygenation) studies especially brain (stroke) heart (heart attack). Melatonin, antiradical mechanisms, toxicity noxious prescription drugs methamphetamine, drug abuse. Experimental findings indicate renders treatment-resistant cancers sensitive various therapeutic agents may useful, due multiple delaying perhaps treating age-related diseases dehumanizing conditions. has been effectively used combat stress, inflammation apoptosis restore tissue function human trials; efficacy supports more extensive use wider studies. The high-safety profile bolsters conclusion. current feeling authors that, view widely diverse beneficial functions have reported for melatonin, merely epiphenomena fundamental, yet-to-be identified basic action(s) ancient molecule.

Язык: Английский

---

Extrapineal melatonin: sources, regulation, and potential functions

Cellular and Molecular Life Sciences, Год журнала: 2014, Номер 71(16), С. 2997 - 3025

Опубликована: Фев. 19, 2014

Язык: Английский

---

Antioxidative Protection by Melatonin: Multiplicity of Mechanisms from Radical Detoxification to Radical Avoidance

Endocrine, Год журнала: 2005, Номер 27(2), С. 119 - 130

Опубликована: Янв. 1, 2005

Язык: Английский

---

Non‐vertebrate melatonin

Journal of Pineal Research, Год журнала: 2003, Номер 34(4), С. 233 - 241

Опубликована: Март 26, 2003

Melatonin has been detected in bacteria, eukaryotic unicells, macroalgae, plants, fungi and various taxa of invertebrates. Although precise determinations are missing many these organisms the roles melatonin still unknown, investigations some species allow more detailed conclusions. Non-vertebrate is not necessarily circadian, if so, always peaking at night, although nocturnal maxima frequently found. In cases under study, major biosynthetic pathway identical with that vertebrates. Mimicking photoperiodic responses concentration changes upon temperature decreases have studied detail only dinoflagellates. an involvement photoperiodism seems conceivable but requires further support. No stimulation flowering demonstrated to date. A participation antioxidative protection might be possible aerobic non-vertebrates, evidence for a contribution physiological levels mostly missing. Protection from stress by oxidotoxins or/and extensions lifespan shown very different organisms, such as dinoflagellate Lingulodinium, ciliate Paramecium, rotifer Philodina Drosophila. can taken up food, findings implications ecophysiology well human nutrition and, regard high medicinal also pharmacology.

Язык: Английский

---

Melatonin: A Mitochondrial Targeting Molecule Involving Mitochondrial Protection and Dynamics

International Journal of Molecular Sciences, Год журнала: 2016, Номер 17(12), С. 2124 - 2124

Опубликована: Дек. 16, 2016

Melatonin has been speculated to be mainly synthesized by mitochondria. This speculation is supported the recent discovery that aralkylamine N-acetyltransferase/serotonin N-acetyltransferase (AANAT/SNAT) localized in mitochondria of oocytes and isolated generate melatonin. We have also melatonin a mitochondria-targeted antioxidant. It accumulates with high concentration against gradient. probably achieved an active transportation via mitochondrial transporter(s). protects scavenging reactive oxygen species (ROS), inhibiting permeability transition pore (MPTP), activating uncoupling proteins (UCPs). Thus, maintains optimal membrane potential preserves functions. In addition, biogenesis dynamics regulated most cases, reduces fission elevates their fusion. Mitochondrial exhibit oscillatory pattern which matches circadian secretory rhythm pinealeocytes other cells. Recently, found promote mitophagy improve homeostasis

Язык: Английский

---

Phytomelatonin: a review

Journal of Experimental Botany, Год журнала: 2008, Номер 60(1), С. 57 - 69

Опубликована: Ноя. 25, 2008

Melatonin (N-acetyl-5-methoxytryptamine) has been detected in a number of plant species. Indeed, there exists evidence that this classically-considered animal indole is actually both synthesized and taken up by plants. Among the actions melatonin may carry out tissues, its role as an antioxidant or growth promoter most strongly supported experimental evidence. Other suggested functional implications include co-ordination photoperiodic responses regulation reproductive physiology, defence cells against apoptosis induced harsh environmental conditions, participation free radical scavenging agent and/or up-regulator certain protective enzymes senescent process. This review presents detailed summary investigations have performed to date (phytomelatonin) field. The purpose bring reader on what known about plants encourage scientists investigate novel research topic; would certainly assist solving numerous questions still remain regarding

Язык: Английский

---

Phytomelatonin: Assisting Plants to Survive and Thrive

Molecules, Год журнала: 2015, Номер 20(4), С. 7396 - 7437

Опубликована: Апрель 22, 2015

This review summarizes the advances that have been made in terms of identified functions melatonin plants. Melatonin is an endogenously-produced molecule all plant species investigated. Its concentration organs varies different tissues, e.g., roots versus leaves, and with their developmental stage. As animals, pathway synthesis plants utilizes tryptophan as essential precursor molecule. inducible when they are exposed to abiotic stresses (extremes temperature, toxins, increased soil salinity, drought, etc.) well biotic (fungal infection). aids root growth, leaf morphology, chlorophyll preservation fruit development. There also evidence exogenously-applied improves seed germination, growth crop yield its application products post-harvest shows ripening may improve food quality. Since was only discovered two decades ago, there still a great deal learn about functional significance It hope authors current will serve stimulus for scientists join endeavor clarifying function this phylogenetically-ancient particularly reference mechanisms by which mediates multiple actions.

Язык: Английский

---

Dual sources of melatonin and evidence for different primary functions

Frontiers in Endocrinology, Год журнала: 2024, Номер 15

Опубликована: Май 14, 2024

This article discusses data showing that mammals, including humans, have two sources of melatonin exhibit different functions. The best-known source melatonin, herein referred to as Source #1, is the pineal gland. In this organ, production circadian with maximal synthesis and release into blood cerebrospinal fluid occurring during night. Of total amount produced in we speculate less than 5% synthesized by rhythm has primary function influencing clock at level suprachiasmatic nucleus (the CSF melatonin) clockwork all peripheral organs via receptor-mediated actions. A second (Source # 2) from multiple tissues throughout body, probably being mitochondria these cells. constitutes bulk mammals concerned metabolic regulation. review emphasizes action determining re-dox homeostasis, but it other critical effects well. Extrapineal does not a released acts locally its cell origin possibly paracrine matter on adjacent factors control/influence extrapineal sites are unknown. We propose concentration cells determined subcellular redox state may be inducible under stressful conditions plant

Язык: Английский

---

Tryptophan is a precursor for melatonin and serotonin biosynthesis in in vitro regenerated St. John's wort ( Hypericum perforatum L. cv. Anthos) plants

Plant Cell Reports, Год журнала: 2000, Номер 19(7), С. 698 - 704

Опубликована: Июнь 13, 2000

Язык: Английский

---

Melatonin increases survival and inhibits oxidative and amyloid pathology in a transgenic model of Alzheimer's disease

Journal of Neurochemistry, Год журнала: 2003, Номер 85(5), С. 1101 - 1108

Опубликована: Май 14, 2003

Increased levels of a 40-42 amino-acid peptide called the amyloid beta protein (A beta) and evidence oxidative damage are early neuropathological markers Alzheimer's disease (AD). Previous investigations have demonstrated that melatonin is decreased during aging process patients with AD more profound reductions this hormone. It has also been recently shown protects neuronal cells from A beta-mediated inhibits formation fibrils in vitro. However, direct relationship between biochemical pathology had not demonstrated. We used transgenic mouse model amyloidosis monitored over time effects administering on brain beta, abnormal nitration, survival mice. report here administration partially inhibited expected time-dependent elevation beta-amyloid, reduced nitration proteins, increased treated These findings may bear relevance to pathogenesis therapy AD.

Язык: Английский

---