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Betreff:
MELATONIN..re
aging & oxygen toxicity..(note Alz & Parkinsons)Reiter...1997 |
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Von: JCMPelican @aol.com |
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Datum: Thu, 14 Jun 2007 01:51:38 EDT |
Aging and oxygen toxicity: Relation
to changes in melatonin
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Journal |
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Publisher |
Springer
Netherlands |
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ISSN |
0161-9152
(Print) 1574-4647 (Online) |
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Issue |
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DOI |
10.1007/s11357-997-0020-2 |
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Pages |
201-213 |
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Subject
Collection |
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SpringerLink
Date |
Wednesday,
May 31, 2006 |
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Department of Cellular and Structural Biology, The University of Texas
Health Science Center, 7703 Floyd Curl Drive, San Antonio, Texas, 78284-7762 |
Abstract: Melatonin (N-acetyl-5-methoxytryptamine) is a chemical
mediator produced in the pineal gland and other sites in the body. The
melatonin found in the blood is derived almost exclusively from the pineal
gland. Since the pineal synthesizes melatonin primarily at night, blood levels
of the indole are also higher at night (5–15 fold) than during the day. Some
individuals on a nightly basis produce twice as much melatonin as others of the
same age. Throughout life, the melatonin rhythm gradually wanes such that, in
advanced age, melatonin production is usually at a minimum.
Melatonin was recently found to be a free
radical scavenger and antioxidant. It has been shown, in the experimental
setting, to protect against both free radical induced DNA damage and oxidative
stress-mediated lipid peroxidation. Pharmacologically, melatonin has been shown
to reduce oxidative damage caused by such toxins as the
chemical carcinogen safrole, carbon tetrachloride, paraquat, bacterial
lipopolysaccharide, kainic acid, δ-aminolevulinic and amyloid β
peptide of Alzheimer’s disease as well as a model of
Parkinson’s disease involving the drug
1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP).
Additionally, the oxidative damage
caused by agents such as ionizing radiation and excessive
exercise is reduced by melatonin. Since free radical-induced molecular
injury may play a significant role in aging, melatonin’s ability to
protect against it suggests a potential
function of melatonin in deferring aging
and age-related, free radical-based diseases. Besides its
ability to abate oxidative damage, other beneficial features of melatonin may
be important in combating the signs of aging; these include
melatonin’s immune-stimulating function, its sleep-promoting
ability, its function as an anti-viral agent, and general
protective actions at the cellular level. Definitive tests of the
specific functions of physiological levels of melatonin in processes of aging
are currently being conducted.
References secured to
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[ Emphasis added by Joanne Mueller....6-13-07....
jcmpelican@aol.com ]