Melatonin is one of the most important antioxidant molecules and certainly the most ancient, as it has been part of biological life for over 3 billion years. It’s present in prokaryotes, which are bacteria, and even in plants. In the human body — aside from having direct antioxidant effects — it also stimulates the synthesis of glutathione and other important antioxidants like superoxide dismutase and catalase.
Melatonin has been here forever … and
its functions have evolved. It has learned to work successfully with
other molecules during this three-billion-year evolution. One of the
molecules with which it collaborates is glutathione … But the
antioxidant activity of melatonin is extremely diverse.
It in
fact is a very good radical scavenger. There are other radical
scavengers — vitamin C, vitamin E and so forth — but melatonin is
superior to those. But beyond that, it stimulates antioxidative enzymes,
especially in mitochondria. Mitochondria are small organelles in the
cell that generate the bulk of the free radicals.
So, it’s very
important to have a good antioxidant at the level of the mitochondria
and melatonin happens to be located and is, in fact, synthesized in the
mitochondria. Melatonin scavenges radicals that are generated, but it
also stimulates something called sirtuin-3, which activates or
deacetylates super oxide dismutase (SOD), which is a very important
antioxidative enzyme.
It also removes free radicals and prevents
the degeneration of the mitochondria, and why this is so important is
because mitochondria are really the center of the action within a cell.
In other words, there’s strong evidence that aging, frailty of aging,
senescence of cells as we age, relate to molecular damage at the level
of the mitochondria, and melatonin seems to be very efficient at
protecting mitochondria from that damage.”
Melatonin increases
glutathione through a genomic effect on the enzyme that regulates the
synthesis of gamma glutamylcysteine synthase, the rate limiting enzyme
in glutathione synthesis. Melatonin activates that enzyme.
Glutathione
tends to be found in high concentrations in cells, although some is
also found, to a lesser degree, in the extracellular space and the
mitochondria. Meanwhile, 95% of the melatonin in your body is
concentrated within the mitochondria inside the cells.
Its
antioxidant effects are quite diverse, but include preventing free
radical generation by enhancing the efficiency of the electron transport
chain so fewer electrons leach onto oxygen molecules to generate super
oxide antiradical....<<<Read More>>>...