Evening exposure to blue light stimulates the expression of the clock gene <i>PER2</i> in humans
European Journal of NeurosciencePublished 1 February 2006
Christian Cajochen, Corinne Jud, Mirjam Münch, Szymon Kobialka, Anna Wirz‐Justice, Urs Albrecht
Citations144
SJR quartileQ2
SJR score1.15
SNIP0.94
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TL;DR
The demonstration of a functional circadian machinery in human buccal samples and its response to light opens the door for investigation of human circadian rhythms at the gene level and their associated disorders.
Abstract
We developed a non-invasive method to measure and quantify human circadian PER2 gene expression in oral mucosa samples and show that this gene oscillates in a circadian (= about a day) fashion. We also have the first evidence that induction of human PER2 expression is stimulated by exposing subjects to 2 h of light in the evening. This increase in PER2 expression was statistically significant in comparison to a non-light control condition only after light at 460 nm (blue) but not after light exposure at 550 nm (green). Our results indicate that the non-image-forming visual system is involved in human circadian gene expression. The demonstration of a functional circadian machinery in human buccal samples and its response to light opens the door for investigation of human circadian rhythms at the gene level and their associated disorders.
Keywords
MedicineAgricultural and Biological SciencesNeuroscience
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