Melatonin: an ancient molecule that makes oxygen metabolically tolerable

@article{Manchester2015MelatoninAA,
  title={Melatonin: an ancient molecule that makes oxygen metabolically tolerable},
  author={Lucien C. Manchester and Ana Coto-Montes and Jos{\'e} Antonio Boga and Lars Peter H. Andersen and Zhou Zhou and Annia Galano and Jerry Vriend and Dun-Xian Tan and Russel Joseph Reiter},
  journal={Journal of Pineal Research},
  year={2015},
  volume={59}
}
Melatonin is remarkably functionally diverse with actions as a free radical scavenger and antioxidant, circadian rhythm regulator, anti‐inflammatory and immunoregulating molecule, and as an oncostatic agent. We hypothesize that the initial and primary function of melatonin in photosynthetic cyanobacteria, which appeared on Earth 3.5–3.2 billion years ago, was as an antioxidant. The evolution of melatonin as an antioxidant by this organism was necessary as photosynthesis is associated with the… 
Melatonin Synthesis and Function: Evolutionary History in Animals and Plants
TLDR
In present day animals, via receptor-mediated means, melatonin functions in the regulation of sleep, modulation of circadian rhythms, enhancement of immunity, as a multifunctional oncostatic agent, etc., while retaining its ability to reduce oxidative stress by processes that are, in part, receptor-independent.
Melatonin as a mitochondria-targeted antioxidant: one of evolution’s best ideas
TLDR
Melatonin’s high concentrations and multiple actions as an antioxidant provide potent antioxidant protection to these organelles which are exposed to abundant free radicals, particularly when they are under high oxidative stress conditions.
Mitochondria: Central Organelles for Melatonin′s Antioxidant and Anti-Aging Actions
TLDR
Melatonin is optimally positioned to scavenge the radicals and reduce the degree of oxidative damage, and in light of the “free radical theory of aging”, high melatonin levels in mitochondria would be expected to protect against age-related organismal decline.
Melatonin: An Alternative Signal to Antioxidant Enzyme Modulation in Plants
TLDR
Exogenous melatonin improves plant tolerance against drought, unfavorable temperatures, salinity, heavy metals stress, acid rain, and pathogen attack and Nitric oxide-melatonin and phytohormone crosstalk provides new avenue of research which might decipher molecular mechanisms of melatonin signaling in plants.
Melatonin: a master regulator of plant development and stress responses.
TLDR
The biosynthesis of melatonin from tryptophan is described, as well as its various degradation pathways in plants, and it is proposed that melatonin is a master regulator in plants.
An Overview of Melatonin as an Antioxidant Molecule: A Biochemical Approach
TLDR
Melatonin prevents degenerative changes in the central nervous system in models of Alzheimer's and Parkinson’s disease and reduces free radical damage to DNA which may lead to cancer and many other situations.
Melatonin: A Multifunctional Factor in Plants
TLDR
The biosynthesis pathway, growth and development regulation, and the environment stress response ofmelatonin in plants are summarized and future research directions and priorities of melatonin in animals and plants are speculated.
Melatonin Mediates Enhancement of Stress Tolerance in Plants
TLDR
Melatonin acted as a powerful growth regulator, bio-stimulator, and antioxidant, which delayed leaf senescence, lessened photosynthesis inhibition, and improved redox homeostasis and the antioxidant system under abiotic and biotic stress conditions.
Melatonin as a Potential Therapeutic Agent: The 1980s
TLDR
It was found that inhibition of GABA type A receptor activity blocked melatonin effect on circadian rhythmicity and locomotor activity in hamsters, analgesia in mice, and anticonvulsant activity and anxiolysis in rats.
Melatonin: A Mitochondrial Targeting Molecule Involving Mitochondrial Protection and Dynamics
TLDR
Melatonin protects mitochondria by scavenging reactive oxygen species (ROS), inhibiting the mitochondrial permeability transition pore (MPTP), and activating uncoupling proteins (UCPs) and maintains the optimal mitochondrial membrane potential and preserves mitochondrial functions.
...
...

References

SHOWING 1-10 OF 248 REFERENCES
Mitochondria and chloroplasts as the original sites of melatonin synthesis: a hypothesis related to melatonin's primary function and evolution in eukaryotes
TLDR
It is the hypothesis that mitochondria and chloroplasts are the original sites of melatonin synthesis in the early stage of endosymbiotic organisms; this synthetic capacity was carried into host eukaryotes by the above‐mentioned bacteria and preserved during evolution.
Melatonin in plants.
TLDR
Because physiologic concentrations of melatonin in the blood are known to correlate with the total antioxidant capacity of the serum, consuming food-stuffs containing melatonin may be helpful in lowering oxidative stress.
The changing biological roles of melatonin during evolution: from an antioxidant to signals of darkness, sexual selection and fitness
TLDR
The changing biological roles of melatonin seem to have evolved from its primary function as an antioxidant, which may indicate senescence in terms of a bio‐clock in many organisms.
One molecule, many derivatives: A never‐ending interaction of melatonin with reactive oxygen and nitrogen species?
TLDR
This review focuses on melatonin metabolism which includes the synthetic rate‐limiting enzymes, synthetic sites, potential regulatory mechanisms, bioavailability in humans, mechanisms of breakdown and functions of its metabolites.
The universal nature, unequal distribution and antioxidant functions of melatonin and its derivatives.
TLDR
The findings from experimental models of numerous diseases overwhelming confirm that this indoleamine would likely have great benefit in aiding humans suffering with conditions that have as their basis tissue and molecular damage resulting from oxygen and nitrogen-based reactants.
Circadian Rhythms, Oxidative Stress, and Antioxidative Defense Mechanisms
TLDR
A general effect of oxidative stress may consist in declines of easily oxidizable signaling molecules such as melatonin, and this can have consequences on the circadian intraorganismal organization and expression of overt rhythms.
Melatonin: a well‐documented antioxidant with conditional pro‐oxidant actions
TLDR
Although the vast majority of studies proved the antioxidant capacity of melatonin and its derivatives, a few studies using cultured cells found that melatonin promoted the generation of ROS at pharmacological concentrations in several tumor and nontumor cells; thus, melatonin functioned as a conditional pro‐oxidant.
Functional Pleiotropy of the Neurohormone Melatonin: Antioxidant Protection and Neuroendocrine Regulation
  • R. Reiter
  • Biology
    Frontiers in Neuroendocrinology
  • 1995
TLDR
The pineal hormone melatonin exhibits remarkable functional versatility and its ability to cross all morphophysiological barriers and to enter every cell, and all subcellular compartments, potentially have important implications for a wide variety of age-related diseases and to aging itself.
Reducing oxidative/nitrosative stress: a newly-discovered genre for melatonin
TLDR
Research in the next decade will help to define the role of melatonin in age-related diseases and in determining successful aging, and improving health and the quality of life in the aged should be an aim of this research.
Melatonin as an antioxidant and its semi-lunar rhythm in green macroalga Ulva sp.
TLDR
Experimental data provide, for the first time, experimental data that support both an antioxidant role for melatonin and its semi-lunar rhythm in macroalgae.
...
...