Melatonin is a hormone synthesized by the pineal gland and then secreted into the blood. It is synthesized through a series of enzymatic reactions, having as a precursor molecule the essential amino acid, tryptophan. It is composed and released in the dark, while not in the light.
Light affects melatonin in two ways: cyclic light-dark alternations modify the rate of melatonin secretion, while short bursts of light of sufficient intensity and duration abruptly suppress its production. Melatonin secretion increases in the dark and reaches its maximum levels around midnight, while at noon it decreases. Thus, it is considered that it participates in the adaptation of the organism to the light-dark cycle of the environment and there are indications that it regulates the biological rhythms.
Studies have suggested that it affects the hormonal function of the anterior and posterior pituitary gland and that nocturnal secretion of melatonin is increased in premenopausal women who use birth control pills.
Beneficial Effects Of Melatonin
Jet Lag Syndrome
Jet Lag is characterized by recurrent sleep disturbance, which causes excessive drowsiness or insomnia and is justified by the lack of synchronization between the sleep program and wakefulness, that are imposed by the needs of the environment. Studies suggest that giving melatonin to people with jet lag syndrome reduces the number of days it takes to get back to normal sleep patterns and boosts alertness.
Melatonin And Sleep Disorders
Melatonin can be used to treat sleep disorders. In situations where endogenous melatonin secretion is reduced, exogenous melatonin administration may reduce sleep disturbances.
Antioxidant Role of Melatonin
The antioxidant action of melatonin is performed through its metabolites. This enables it to protect the body from oxidative stress. Rapid consumption of melatonin in intense stress may be a defense mechanism of the body, in which melatonin is used as a defense molecule against oxidative damage.
Melatonin And Skin Protection
The human skin is an essential defense “wall” against a wide variety of environmental toxins. In this way, it helps maintain homeostasis. However, it often shows signs of degeneration, which lead to the aging phenotype and cause many other pathological processes. In fact, when the skin is exposed to toxic agents and chemicals, such as radiation, various chemicals, pollution and microorganisms, it needs protective chemical molecules. Melatonin plays an important role in maintaining good skin health. It is a powerful free radical scavenger with antioxidant and anti-inflammatory function. Melatonin has also been shown to help significantly in wound healing and to treat many skin conditions, such as atopic dermatitis, seborrheic dermatitis and vitiligo.
Melatonin And Cardiovascular System
It is well known, from clinical studies, that patients with coronary heart disease have reduced melatonin levels. High levels of LDL cholesterol are also associated with low levels of melatonin. Cardiovascular protection of melatonin, in combination with its antioxidant activity, has been observed in experimental models of myocardial infarction. Furthermore, those with hypertension have been shown to have a reduced rate of melatonin production. Several studies have suggested that melatonin administration in patients with hypertension reduced diastolic and systolic blood pressure.
Melatonin And Gastrointestinal System
Intense stress alters the gastrointestinal tract. Melatonin inhibits the development of these lesions and accelerates the healing of acute gastric ulcers. Blood flow to the gastric mucosa is increased thanks to the antioxidant action of melatonin.
Melatonin And Neurological Disorders
With age, melatonin levels decrease. Decreased melatonin levels are associated with the development of neurological disorders, such as Parkison’s and Alzheimer’s disease. Oxidative stress is heavily involved in the pathogenesis of these diseases. The antioxidant activity of melatonin could help treat patients who suffer from these diseases.
Melatonin And Diabetes
Diabetes mellitus is characterized by the increased presence of oxygen free radicals. Insulin resistance is attributed to the presence of these oxidizing bodies. Melatonin administration can significantly delay the complications which are caused by diabetes, such as retinopathy and kidney disease, as it balances free radicals and has antioxidant properties.
Administration of Melatonin
Melatonin is a hormone synthesized by the pineal gland and has beneficial properties, thus benefiting the human body in various ways. It is a key regulator of circadian rhythms and recent data suggest that it has antioxidant activity. Its anti-inflammatory properties allow melatonin to regulate mitochondrial homeostasis, inhibit apoptosis and enhance hair follicle growth. All these properties emphasize the important role that melatonin plays in protecting the skin from damage caused by external factors. It goes without saying that taking natural (biomimetic) melatonin should be supervised by a specialist doctor, who is responsible for the individual administration of this hormone. Only through this personalized pathway the human body will be able to enjoy all the benefits of melatonin.
- Cipolla-Neto, J.; Amaral, F.G.D. Melatonin as a hormone: New physiological and clinical insights. Endocr. Rev. 2018, 39, 990–1028.
- Do Amaral, F.G.; Cipolla-Neto, J. A brief review about melatonin, a pineal hormone. Arch. Endocrinol. Metab. 2018, 62, 472–479.
- Bouatia-Naji, N.; Bonnefond, A.; Cavalcanti-Proença, C.; Sparsø, T.; Holmkvist, J.; Marchand, M.; Delplanque, J.; Lobbens, S.; Rocheleau, G.; Durand, E.; et al. A variant near MTNR1B is associated with increased fasting plasma glucose levels and type 2 diabetes risk. Nat. Genet. 2009, 41, 89–94.
- Jonsson, L.; Ljunggren, E.; Bremer, A.; Pedersen, C.; Landén, M.; Thuresson, K.; Giacobini, M.; Melke, J.
- Mutation screening of melatonin-related genes in patients with autism spectrum disorders. BMC Med. Genom. 2010, 3, 10.
- Campos, L.A.; Cipolla-Neto, J.; Amaral, F.G.; Michelini, L.C.; Bader, M.; Baltatu, O.C.
- The Angiotensin-melatonin axis. Int. J. Hypertens 2013, 2013, 521783.
- Baltatu, O.C.; Amaral, F.G.; Campos, L.A.; Cipolla-Neto, J. Melatonin, mitochondria and hypertension. Cell Mol. Life Sci. 2017, 74, 3955–3964.
- Jiki, Z.; Lecour, S.; Nduhirabandi, F. Cardiovascular benefits of dietary melatonin: A myth or a reality? Front. Physiol. 2018, 9, 528.
- Ramos, E.; Patiño, P.; Reiter, R.J.; Gil-Martín, E.; López-Muñoz, F.; Romero, A. Melatonin: A hypothesis for Kawasaki disease treatment. Med. Hypotheses 2018, 119, 6–10.
- Dominguez-Rodriguez, A.; Abreu-Gonzalez, P.; Avanzas, P. The role of melatonin in acute myocardialinfarction. Front. Biosci. 2012, 17, 2433–2441.
- Dominguez-Rodriguez, A.; Abreu-Gonzalez, P.; Reiter, R.J. Clinical aspects of melatonin in the acute coronarysyndrome. Curr. Vasc. Pharm. 2009, 7, 367–373.
- Slominski, A.T.; Hardeland, R.; Zmijewski, M.A.; Slominski, R.M.; Reiter, R.J.; Paus, R. Melatonin: Acutaneousperspective on its production, metabolism, and functions. J. Investig. Dermatol. 2018, 138, 490–499.
- Slominski, A.; Tobin, D.J.; Zmijewski, M.A.; Wortsman, J.; Paus, R. Melatonin in the skin: Synthesis,metabolism and functions. Trends Endocrinol. Metab. 2008, 19, 17–24.menstrual cycle in premenopausal women. Clin Endocrinol 1998, 49:209-216
Leave a Reply