[The inter-individual variability of circadian period length in human skin cells].

The Period Length of Fibroblast Circadian Gene Expression Varies Widely among Human Individuals

Mammalian circadian behavior is governed by a central clock in the suprachiasmatic nucleus of the brain hypothalamus, and its intrinsic period length is believed to affect the phase of daily activities. Measurement of this period length, normally accomplished by prolonged subject observation, is difficult and costly in humans. Because a circadian clock similar to that of the suprachiasmatic nuc...

Inter-individual Variability of Coumarin 7-hydroxylation (CYP2A6 activity) in an Iranian Population

Amyloid-β–Induced Changes in Molecular Clock Properties and Cellular Bioenergetics

Ageing is an inevitable biological process that results in a progressive structural and functional decline, as well as biochemical alterations that altogether lead to reduced ability to adapt to environmental changes. As clock oscillations and clock-controlled rhythms are not resilient to the aging process, aging of the circadian system may also increase susceptibility to age-related pathologie...

Persistent Cell-Autonomous Circadian Oscillations in Fibroblasts Revealed by Six-Week Single-Cell Imaging of PER2::LUC Bioluminescence

Biological oscillators naturally exhibit stochastic fluctuations in period and amplitude due to the random nature of molecular reactions. Accurately measuring the precision of noisy oscillators and the heterogeneity in period and strength of rhythmicity across a population of cells requires single-cell recordings of sufficient length to fully represent the variability of oscillations. We found ...

Wavelet Analysis Reveals Period Wandering in Circadian Neurons

Period variability in circadian oscillators is a consequence of the stochastic nature of the underlying chemical processes. This variability is significant when considering the interaction of circadian neurons in the suprachiasmatic nucleus (SCN) and their response to external signals. We use the Morlet continuous wavelet transform to measure the period of the noisy nonstationary circadian osci...