Metabolic syndrome, dyssomnia, and melatonin

In recent years, there has been an interest in studying the specifics of the relationships between metabolic syndrome (MetS), sleep disorders and melatonin (MEL). Dyssomnia and insomnia are important risk factors for insulin resistance, obesity, MetS, and type 2 diabetes mellitus with a degree of influence similar to traditional factors. Thus, the treatment of dyssomnia is one of the key tasks in the prevention and treatment of MetS. The regulation of sleep and circadian rhythms by exogenous intervention (in particular, the use of melatonergic drugs) is likely to play a central role in the prevention and treatment of dyssomnia in MetS. MEL acts as a powerful antioxidant that can cross the blood-brain barrier, suppress oxidative stress, chronic inflammation, and interact with the gut microbiome. From a clinical point of view, an imbalance of MEL may indicate a “darkness deficit”. It has been proven that the neurohormone has systemic effects due to its mechanisms of action, the potential to influence the course of many chronic diseases. Currently, melatonergic drugs are approved exclusively for the treatment of insomnia, jetlag, and depression accompanied by sleep disorders. However, MEL potentially has therapeutic properties in the treatment of neurodegenerative diseases, post-traumatic stress disorder, neuropsychiatric disorders, dementia, autoimmune and allergic diseases. The increasing need for the use of MEL products has prompted the search for safe but environmentally friendly medicines. It is reported that phytomelatonin may have advantages related to improved bioavailability and efficacy. The purpose of this review is to analyze the specifics of the relationship between MetS, dyssomnia, and MEL. The search was conducted in Scopus, Science Direct (from Else­vier), and PubMed, including MEDLINE databases. The keywords used were “metabolic syndrome”, “dyssomnia”, “insomnia”, “obstructive sleep apnea”, and “melatonin”. We conducted a manual search of the bibliography of publications to identify research results that were eluded during the online search.