title: [Aging and circadian clock gene expression in peripheral tissues in rats].
abstract: Aging is associated with alterations of the circadian rhythms (shortened amplitude and phase-advance). We studied by quantitative RT-PCR the influence of aging on the expression of circadian clock genes (Clock, Bmal1, Cry1,2, Per1-3) in peripheral tissues (liver and heart) of middle-aged (13 months) and old (27 months) rats of the Wag/Rij strain exposed to a 12 hours light/12 hours dark cycle. Rats were killed at the light-dark transition (8 am and 8 pm). In the liver, Per, Cry et Bmal1 genes showed a morning/evening difference of expression; in addition, old rats exhibited a significant decrease of Per gene expression in the evening vs middle-aged rats. The heart showed similar profiles with only a tendency toward a decrease of Per expression and an increased Bmal1 expression in the evening in old rats. These results show that aging is associated with circadian gene expression changes.
authors.affiliation: Service de radioanalyse, hôpital cardiologique, 59, boulevard Pinel, 69677 Bron cedex, France. francine.claustrat@chu-lyon.fr
authors.forename: F
authors.initials: F
authors.lastname: Claustrat
authors.forename: I
authors.initials: I
authors.lastname: Fournier
authors.forename: G
authors.initials: G
authors.lastname: Geelen
authors.forename: J
authors.initials: J
authors.lastname: Brun
authors.forename: B
authors.initials: B
authors.lastname: Corman
authors.forename: B
authors.initials: B
authors.lastname: Claustrat
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D002940:Circadian Rhythm / Q000502:physiology*; D056931:Cryptochromes; D005260:Female; D005420:Flavoproteins / Q000235:genetics; D005786:Gene Expression Regulation / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic
chemical_list: C538965:Cry1 protein, rat; D056931:Cryptochromes; D005420:Flavoproteins