About this Research Topic
Correct regulation and maintenance of physiological processes, such as cardiovascular and renal activities, hepatic metabolism, sleep and immune functions are required for the efficiency and survival of organisms. In addition, the activities associated with these physiological processes are organized in a daily manner: During times of behavioral activity, corresponding to the daytime in diurnal animals including humans, physiology is given over to catabolic processes, whereas during behavioral quiescence, night for humans and other diurnal species, anabolic functions of growth, repair and consolidation dominate.
Circadian clocks regulate most physiological functions in a broad spectrum of organisms ranging from bacteria to humans. They generate daily changes (circadian rhythms) in biochemical, physiological and behavioral processes. In order to maximize an organism’s efficiency, circadian clocks are synchronized, or entrained, to the external day-night cycle by environmental time cues, such as light, and behavioral or physiological feedback, such as food timing and exercise. Circadian systems can be divided into three conceptual components: 1) Pacemakers, dedicated to generating and sustaining circadian rhythms by receiving and integrating signals from external and internal time cues; 2) Input pathways, through which time cues are perceived and act upon pacemakers; and 3) Output mechanisms, via which a pacemaker exerts its influence on wider physiology and behavior. Disrupting circadian function has profound effects on survival and health and is linked to a plethora of diseases, including obesity and diabetes, respiratory and cardiovascular diseases, cancer, and disorders affecting sleep, mood and mental health. Moreover, a number of chronobiological links and implications exist for the current global coronavirus pandemic.
This Research Topic will focus on novel molecular and physiological mechanisms underlying the regulation of circadian clock systems, aiming to further understand the manner in which defects in such regulation are related to deficits in physiology and behavior that lead to disease and ill-health. Submissions may feature current topical areas including, but not limited to, the chronobiology of metabolism, food-timing and exercise, circadian immunology, melatonin and biology of the gut microbiome. We may also expect to attract submissions related to circadian function in skin and muscle tissue, the roles of dopamine and GABA in circadian biology, membrane physiology, and the involvement of circadian processes in neurodegenerative diseases, as well as sleep, mood and affective disorders. Given the importance of respiratory biology for the manifestation of COVID-19, and recent advances over the last decade related to circadian function in the respiratory tract, focused largely on immunological issues, we would also anticipate receiving submissions related to this area with current, particularly wide-reaching, global implications.
Submissions are expected to span a range of interdisciplinary approaches, covering levels of organization from molecular mechanisms to physiology and behavior, applied to a variety of experimental systems and model organisms. Original research, reviews and commentaries will all be considered.
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.