4 Headache Medicine, v.8, n.1, p.4-5, Jan./Feb./Mar. 2017
he secretion of melatonin by the pineal gland undergoes a significant
influence of light. In the absence of light, there is a release of melatonin, a hormone
that exerts major physiological actions to maintain a healthy life. During the last 100
thousand years, the brain of Homo sapiens was under a natural control of the amount
of light that reach the eyes, e.g., near the equator a circadian rhythm of approximately
12 hours of daylight: 12 hours darkness. A drastic change in the light-dark cycle
occurred in the last 200 years. The population in the big cities regularly is continuously
working at night in bright environments, watching television, playing on the computer;
thus, a series of activities are performed with an artificial light source on, actually
inhibiting the secretion of melatonin by the pineal gland.
The way that the eyes use to inform the cells of the body that is day or night is
done by the decrease or increase, respectively, in the concentration of melatonin in
the blood. With present-day technology and varied sources of artificial light, there is
an inadequate pattern of signaling to the organism of the external environment. This
reduction in the duration of darkness (absence of light), often irregular, perturbs and
confounds the brain interpretation of natural phenomena that would regulate
physiological functions as in the example of the sleep cycle, hormonal secretion,
among other biological cycles.
Some scientists suggest that after 45 years of age melatonin should be
supplemented because there is a significant drop in blood concentration of this
hormone in the fifth decade of life. Melatonin has been used for several conditions,
such as insomnia, in the fight against pain, as an antineoplastic drug and to attenuate
the production of free radicals, used thus to prevent aging.
Paulo Faro,
(1)
in this issue, is commenting two excellent articles
(2,3)
published by
Brazilian colleagues on melatonin and indomethacin. The molecular structure of
melatonin is very similar to that of indomethacin, and, curiously, some types of
headache can be individually treated by both drugs.
Following the suggestion of Mario Peres, I have used melatonin to treat various
forms of headache, including cluster headache and migraine associated or not to
overuse of analgesic, recommending oral intake at 7:00 p.m. In addition, since
melatonin's biological half-life is approximately 30 to 100 minutes a second dose
may be repeated a few hours later.
Pineal gland, melatonin and the illuminated nights in the
XXI century
Glândula pineal, melatonina e as noites iluminadas do
século XXI
T
EDITORIAL
Headache Medicine, v.8, n.1, p.4-5, Jan./Feb./Mar. 2017 5
Marcelo Valença
Neurosurgery and Neurology Unit, Federal University of Pernambuco
Recife - Pernambuco, Brazil
Editor da Headache Medicine
As the good news recently revealed by AVISA (Agência Nacional de Vigilância
Sanitária), we now know that melatonin was authorized in Brazil to be produced by
compounding pharmacies.
REFERENCES
1. Santos PSF. Indometacina e Melatonina: duas irmãs que continuam reinando. Headache Med 2017;
(1):26-7.
2. Bordini EC, Bordini CA, Woldeamanuel YW, Rapoport AM. Indomethacin Responsive Headaches: Exhaustive
Systematic Review with Pooled Analysis and Critical Appraisal of 81 Published Clinical Studies. Headache.
2016 Feb;56(2):422-35.
3. Gonçalves AL, Martini Ferreira A, Ribeiro RT, Zukerman E, Cipolla-Neto J, Peres MF. Randomised clinical
trial comparing melatonin 3 mg, amitriptyline 25 mg and placebo for migraine prevention. J Neurol
Neurosurg Psychiatry. 2016 Oct;87(10):1127-32.
PINEAL GLAND, MELATONIN AND THE ILLUMINATED NIGHTS IN THE XXI CENTURY
