Mood phenotypes in rodent models with circadian disturbances

Area of Science:

• Neuroscience
• Chronobiology
• Psychiatry

Background:

• Circadian rhythms, regulated by the internal circadian clock, govern numerous physiological functions, including sleep-wake cycles and body temperature.
• Beyond basic physiology, circadian clock regulation extends to higher brain functions, with growing evidence linking it to mood disorders like depression.
• The precise mechanisms underlying the connection between the circadian clock and depression remain largely unclear.

Purpose of the Study:

• To review and synthesize findings from rodent models exhibiting disrupted circadian rhythms.
• To investigate the impact of these circadian disturbances on depression-related behaviors and responses.
• To elucidate the potential causal link between circadian clock dysfunction and the development of depression.

Main Methods:

• Overview of existing literature on rodent models with experimentally induced circadian rhythm disturbances.
• Analysis of studies utilizing clock gene mutations to model circadian disruption.
• Examination of research employing artifactual interventions to alter circadian timing in rodents.

Main Results:

• Rodent models with disrupted circadian rhythms display various depression-related responses.
• Specific clock gene mutations are associated with altered mood and behavior.
• Environmental or artificial interventions affecting circadian timing can induce or exacerbate depression-like phenotypes in animal models.

Conclusions:

• Rodent models with circadian disturbances provide valuable insights into the functional relationship between the circadian clock and depression.
• These models support a causal link between circadian system disruption and depression.
• Further research using these models is crucial for understanding the neurobiological underpinnings of circadian-related mood disorders.