Shedding some light on the relationship between chronobiology and aging.

The life of most organisms is, beyond other influences, controlled by two central biological events: Biological rhythms based on the timely regulation of physiological processes, and the biology of aging. Circadian rhythms (CRs) are established by a genetically encoded circadian program, controlling a multitude of biological cycles and enabling an individual to adjust to periodic environmental changes during daytime, seasons, and lifetime. Thus, its conserved nature allows to synchronize metabolic, endocrine, behavioral, and complex intracellular events across a 24-hour day/night cycle.

Aging is an equally complex process, which is affected by a plethora of exogenous and endogenous factors, and which impacts virtually all crucial biological processes by a progressive loss of cellular functions. It is well established that aging interferes with the regulation of the circadian system, which, in return, contributes to the manifestation and progression of aging-related diseases. Furthermore, age-independent alterations of the circadian system can result in premature aging of vertebrates and invertebrates, suggesting a direct mutual interrelation between both processes.

However, it is not well studied in how far changes in the expression of CR core genes and their downstream targets are responsible for age-related variations in CR regulation. Moreover, it is unclear to what extent these changes in CR gene regulatory patterns may overlap in distinct tissues and species. A related open question remains as to whether a conserved age-related pattern of CR gene expression alterations might exist that will be common to and retraceable across different species and tissues.

In how far CR regulation is causal to or a consequence of the aging process still remains to be explored.

In our study (that we just have published as a research article in the Journal Aging US) we yield a comprehensive new dataset linking CR factors to physiological aging across evolutionarily distinct species. Our results will support to dissect the alterations in chronobiology associated to latent or manifest disease conditions from CR characteristics in healthy aging and contribute to the identification of interventions that can improve the well-being of the elderly and extend a healthy lifespan.