Rhythm and mood: Relationships between the circadian clock and mood-related behavior.

Abstract

Mood disorders are multifactorial and heterogeneous diseases caused by the interplay of several genetic and environmental factors. In humans, mood disorders are often accompanied by abnormalities in the organization of the circadian system, which normally synchronizes activities and functions of cells and tissues. Studies on animal models suggest that the basic circadian clock mechanism, which runs in essentially all cells, is implicated in the modulation of biological phenomena regulating affective behaviors. In particular, recent findings highlight the importance of the circadian clock mechanisms in neurological pathways involved in mood, such as monoaminergic neurotransmission, hypothalamus-pituitary-adrenal axis regulation, suprachiasmatic nucleus and olfactory bulb activities, and neurogenesis. Defects at the level of both, the circadian clock mechanism and system, may contribute to the etiology of mood disorders. Modification of the circadian system using chronotherapy appears to be an effective treatment for mood disorders. Additionally, understanding the role of circadian clock mechanisms, which affect the regulation of different mood pathways, will open up the possibility for targeted pharmacological treatments.

Happiness and Defense Styles in Psychiatrists

“…This association remained in the multivariate analysis. In this regard, it is known that there is a strong causal relationship between changes in both directions in the circadian rhythm disorders and mood (Schnell et al, 2014) and also known is the negative relationship between the presence of mental disorders, specifically depression, and happiness (Binder and Coad, 2013). Thus, while having a good level of happiness should provide good sleep quality, sleeping well should also contribute to the feeling of subjective well-being.…”

Genetic Disruption of Circadian Rhythms in the Suprachiasmatic Nucleus Causes Helplessness, Behavioral Despair, and Anxiety-like Behavior in Mice

“…Mechanistic connections between disturbed circadian clocks and mood regulation have been evaluated before in rodent models (7,8,11). However, in previous studies, it was unclear whether circadian or noncircadian changes led to abnormal mood-related behavior (13).…”

A lifetime of neurogenesis in the olfactory system

“…Finally, an interesting future question may concern circadian rhythms, which are disrupted with aging (Goergen et al, 2002; Campos Costa et al, 2013). Circadian rhythms also regulate neurogenesis (Schnell et al, 2014) and OB activity (Granados-Fuentes et al, 2006); hence, a disregulation of clock genes such as Per1 and Per2 may be a source of explanation for the decline in proliferation observed with aging in the olfactory epithelia.…”