Melatonin: the hormone that controls sleep and seasonal rhythms.

Seven uses and functions of this hormone.

It is a well-known fact that humans, like all other animals, need to sleep.. Sleep is a basic physiological function, a mechanism that allows the organism (and especially the brain) to rest and repair itself. However, sleep is not a single, unchanging process, but goes through different phases along the way. Moreover, it is a process that is not voluntary, but depends on circadian rhythms.

These rhythms regulate the sleep-wake cycle according to the biological needs of the organism and the time of day. This regulation, as well as the seasonal patterns that occur in other animals, are mainly due to the action of a hormone: melatonin

Melatonin: what are we talking about?

Melatonin is a hormone secreted mainly by the epiphysis or pineal gland from tryptophan and serotonin. It is a very fat-soluble hormone, with great facility to penetrate the blood-brain barrier and inside the cells. This hormone is generated when the retina perceives the absence of light, producing the maximum peak of this hormone during the night and decreasing in the presence of light.

The process of melatonin production is as follows: the retina senses the presence or absence of light, passing this information to the optic nerve, then to the suprachiasmatic nucleus and from there to the superior cervical ganglion, which reaches the epiphysis. The latter proceeds to carry out a series of reactions that culminate in the production of melatonin, which is distributed throughout the rest of the organism. Apart from its origin in the brain, it also appears in the retina, liver, kidneys, intestine, immune cells and in the female endometrium.

Melatonin receptors

Melatonin has its receptors in various parts of the body, both inside and outside the brain.The melatonin receptors in the brain, both inside and outside the brain, produce different effects on the functioning of the body. The brain melatonin receptors have an effect on circadian rhythms, the non-neural receptors influence reproduction, and finally the peripheral receptors have different effects depending on their location.

Thus, the functions of melatonin are many and varied, affecting various systems of the organism, although the function for which it is best known and studied is that of the control of circadian rhythms, mainly carrying out a chronological action.It mainly carries out a chronobiological action in the suprachiasmatic nucleus. That is to say, this hormone contributes to establish in which moments we pass from sleep to wakefulness and vice versa. The maximum production usually occurs concretely around an hour and a half after falling asleep, contributing to induce deep sleep.

Effects beyond sleep

Apart from the function of regulating the sleep-wake cycle, recent research has shown that this hormone has a great utility in numerous systems. It is actively involved in the regulation of seasonal and reproductive phenomena, such as estrus in animals. It also plays a role in long-term memory enhancement..

The immune system is also affected by this hormone (its efficiency is reduced during its absence) and it has an important antioxidant effect that counteracts the excess of free radicals. Thus, this hormone also participates in the processes of growth and aging.

Exogenous use of melatonin

Although it is an endogenous hormone, manufactured by the body itself, melatonin has been artificially synthesized and marketed as an endogenous hormone, melatonin has been artificially synthesized and marketed as a dietary supplement. dietary supplement (although it is not yet permitted as a drug due to the little research available and the inconclusive results obtained so far).

Some of the uses that have been given to it are the following:

1. sleep disorders 2.

Melatonin has been used as a treatment for sleep disorders.. Specifically, it is noted for its ability to improve sleep adjustment in cases of jet lagIt has been shown that when administered around bedtime at the point of destination, jet lag is considerably reduced. For this reason it is widely used in circadian rhythm disorders. It also produces benefits in delayed sleep phase syndrome, as well as in sleep disturbances in the case of individuals who work late at night.

However, in the case of primary insomnia or insomnia secondary to another disorder, while it has been shown to decrease sleep latency and improve the has been shown to decrease sleep latency and improve the amount of time slept, in some studies it has not been shown to reduce sleep latency and improve the amount of time slept.In some studies it has not shown a greater effect than placebo, being more effective the use of benzodiazepines and always prioritizing sleep hygiene.

Some research shows that the administration of this substance produces improvement in other disorders due to the improvement in sleep patterns, such as autism or infantile epilepsy. However, further research would be required.

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2. Action on reproduction and growth

It has been observed that melatonin administration is linked not only to sleep patterns, but also to other seasonal processes.

In animals, it has been shown to affect and modulate oestrus periods.. In humans, it has been observed that the administration of this hormone affects growth, making it evident that it has an effect on the time of onset of puberty. An excess of this hormone can delay puberty, while a deficiency can cause it to advance.

3. Headaches

Research indicates that melatonin supplementation can act preventively to avoid migraines..

4. Mood disorders

Different studies have shown the efficacy of melatonin application to improve the condition of patients with depressive disorders, especially in the case of seasonal affective disorder.

5. Aging and dementias

Melatonin production is not constant throughout life, with a significant and progressive decline from adolescence to the end of life (which helps explain why the elderly have shorter and more frequent sleep periods).There is a significant and progressive decrease from adolescence to the end of life (which helps to explain why the elderly have shorter and more frequent sleep periods).

In addition, much of the effects of aging are due to the presence of free radicals. Furthermore, different types of free radicals and oxidation have also been linked to dementia processes such as Alzheimer's or Parkinson's disease.

Since melatonin has been shown to be one of the major endogenous antioxidants available to us, several tests have shown that the administration of melatonin decreases oxidative damage in the different systems of the organism, thereby may be an aid in delaying brain aging and prolonging intellectual function in dementia. in dementia cases.

6. Cancer

The application of melatonin in some Cancer patients seems to reduce tumor growth and prolong survival, being observed as a possible treatment to be combined with chemotherapy. This effect seems to be due to antiproliferative properties and to the potentiation of the effects of chemotherapy, especially in cases of cancers that depend on reproductive cells.

7. Other inconclusive research

As mentioned above, melatonin has certain effects on the immune system, acting as a modulator of the immune system.. In addition to being a potent antioxidant, it has been found to act on receptors on T lymphocytes, contributing to the production of immunoglobulin.

It has been studied the possibility that it may contribute to slow HIV replication, so that it could be applied as a booster treatment. Its usefulness in cases of different cancers has also been explored. However, the results are inconclusive.

Bibliographic references:

• Benitez-King, G.; Ramirez-Rodriguez, G.; Ortiz, L. et al. (2004) The neuronal cytoskeleton as a potential therapeutic target in neurodegenerative diseases and schizophrenia. Curr Drug Targets CNS Neurol Disord; 3: 515-533.

• Boutin, J.; Audinot, V.; Ferry, G. and Delagrange, P. (2005). "Molecular tools to study melatonin pathways and actions.". Trends Pharmacol Sci 26(8): 412-9.

• Carrillo, A.; Guerrero,J.M.; Lardone, P.J. et al. (2005). A review of the multiple actions of melatonin on the immune system. Endocrine, vol. 27, 189-200.

• Dodick, D.W. & Capobianco, D.J. (2001). "Treatment and management of cluster headache".Curr Pain Headache Rep5 (1): 83-91.

• Guerrero, J.M.; Carrillo, A. and Lardone, P. (2007). Melatonin. Research and Science. 30-38

• Martinez, B.; Sanchez, Y.; Urra, K.; Thomas, Y.D. & Burgos, J.L.(2012). Dark hormone. Rev Latinoamer Patol Clin, Vol. 59, 4, pp 222-232.

• Lewis, A. (2006). Melatonin and the Biological Clock. New York, NY: Mc Graw-Hill; p. 7.

• Portugal, F.L et al. (2010) Ação da melatonina sobre a apoptose e fator de crescimento endotelial vascular no córtex da adrenal de ratas pinealectomizadas. Rev Bras Ginecol Obstet. 32 (8).

• Reiter, R.J.; Tan, D.X.; Gitto, E. et al. (2004). Pharmacological utility of melatonin in reducing oxidative cellular and molecular damage. Polish Journal of Pharmacology and Pharmacy, vol.56, 159-170.

• Reyes, B.M.; Velázquez-Panigua, M. and Prieto-Gómez, B. (2009). Melatonin and neuropathologies. Rev.Fac.Med. UNAM, Vol.52, 3. Center for Genomic Sciences. School of Medicine, UNAM.