Circadian Rhythms, Melatonin and Depression

Abstract

The master biological clock situated in the suprachiasmatic nuclei of the anterior hypothalamus plays a vital role in orchestrating the circadian rhythms of multiple biological processes. Increasing evidence points to a role of the biological clock in the development of depression. In seasonal depression and in bipolar disorders it seems likely that the circadian system plays a vital role in the genesis of the disorder. For major unipolar depressive disorder (MDD) available data suggest a primary involvement of the circadian system but further and larger studies are necessary to conclude. Melatonin and melatonin agonists have chronobiotic effects, which mean that they can readjust the circadian system. Seasonal affective disorders and mood disturbances caused by circadian malfunction are theoretically treatable by manipulating the circadian system using chronobiotic drugs, chronotherapy or bright light therapy. In MDD, melatonin alone has no antidepressant action but novel melatoninergic compounds demonstrate antidepressant properties. Of these, the most advanced is the novel melatonin agonist agomelatine, which combines joint MT1 and MT2 agonism with 5-HT(2C) receptor antagonism. Adding a chronobiotic effect to the inhibition of 5-HT(2C) receptors may explain the rapid impact of agomelatine on depression, since studies showed that agomelatine had an early impact on sleep quality and alertness at awakening. Further studies are necessary in order to better characterize the effect of agomelatine and other novel melatoninergic drugs on the circadian system of MDD patients. In summary, antidepressants with intrinsic chronobiotic properties offer a novel approach to treatment of depression.

Involuntary admissions in Italy: the impact of seasonality

“…Other studies showed, in addition to the main peak in spring/summer, a lower frequency of manic involuntary admissions in autumn (Cassidy & Carroll 2002;Lee et al 2002;Morken et al 2002;Volpe and Del Porto 2006;Lee et al 2007;Volpe et al 2010;Yang et al 2013;Geoffroy et al 2014). Furthermore, patients with bipolar disorder and seasonal-affective disorder have a higher light sensitivity compared to healthy controls and patients affected by major depressive disorder, as a result of melatoninergic, serotoninergic and dopaminergic neurotransmissions (Nathan et al 1999;Quera Salva et al 2011). Moreover, another factor influencing environmental regulation of biorhythm is represented by changes in photoperiod through different seasons (Abreu & Braganca 2015).…”

Circadian rhythm characteristics, poor sleep quality, daytime sleepiness and common psychiatric disorders among Thai college students

“…Melatonin, which is a hormone produced in the pineal gland of the brain (Reiter, 1991), has the ability to manipulate circadian systems (Quera Salva et al, 2011) and affect internal neurohormonal regulation (Chelminski et al, 1999). Studies have shown that individuals with low levels of endogenous melatonin (those who do not have the normal nocturnal peak in secretion) are more likely to have symptoms of CPDs (Malhi & Kuiper, 2013).…”

Tipología circadiana y problemas de salud mental

“…Las relaciones existentes entre la tipología circadiana y los diversos problemas de salud mental analizados apuntan a una implicación de la tipología circadiana en el inicio, curso, remisión y recaída de dichas alteraciones, por lo que ésta debería tenerse en cuenta en la evaluación y tratamiento de pacientes, así como en la prevención de estos problemas en población de riesgo. La terapia cronobiológica (hábitos conductuales, terapia lumínica o terapia farmacológica con melatonina) se postula como una novedosa herramienta que puede resultar de gran utilidad en el tratamiento de diversos problemas de salud mental tales como el trastorno por uso de sustancias y los trastornos de ansiedad (Adan, 2013), trastornos del estado de ánimo (Anderson, 2010;Quera-Salva et al, 2011;Wirz-Justice, 2003;Wirz-Justice et al, 2005), TDAH (Rybak, McNeely, Mackenzie, Jain y Levitan, 2006), problemas de sueño (Gammack, 2008;Kledzik y Thome, 2011) y esquizofrenia (Kledzik y Thome, 2011), si bien se requieren estudios con muestras amplias de sujetos que permitan desarrollar recomendaciones de consenso.…”