Circadian disruption induced by light at night accelerates aging and promotes tumorigenesis in rats
Circadian disruption induced by light at night accelerates aging and promotes
tumorigenesis in rats
Irina A. Vinogradova, Vladimir N. Anisimov, Andrey V. Bukalev, Anna V.Semenchenko, Mark A. Zabezhinski
Abstract: We evaluated the effect of various light/dark regimens on the survival, life span and tumorigenesis in rats. Two hundred eight male and 203 females LIO rats were subdivided into 4 groups and kept at various light/dark regimens: standard 12:12 light/dark (LD); natural lighting of the North-West of Russia (NL); constant light (LL), and constant darkness (DD) since the age of 25 days until natural death. We found that exposure to NL and LL regimens accelerated development of metabolic syndrome and spontaneous tumorigenesis, shortened life span both in male and females rats as compared to the standard LD regimen. We conclude that circadian disruption induced by light-at-night accelerates aging and promotes tumorigenesis in rats. This observation supports the conclusion of the International Agency Research on Cancer that shiftwork that involves circadian disruption is probably carcinogenic to humans.