title: Feeding cues and injected nutrients induce acute expression of multiple clock genes in the mouse liver.
abstract: The circadian clock is closely associated with energy metabolism. The liver clock can rapidly adapt to a new feeding cycle within a few days, whereas the lung clock is gradually entrained over one week. However, the mechanism underlying tissue-specific clock resetting is not fully understood. To characterize the rapid response to feeding cues in the liver clock, we examined the effects of a single time-delayed feeding on circadian rhythms in the liver and lungs of Per2::Luc reporter knockin mice. After adapting to a night-time restricted feeding schedule, the mice were fed according to a 4, 8, or 13 h delayed schedule on the last day. The phase of the liver clock was delayed in all groups with delayed feeding, whereas the lung clock remained unaffected. We then examined the acute response of clock and metabolism-related genes in the liver using focused DNA-microarrays. Clock mutant mice were bred under constant light to attenuate the endogenous circadian rhythm, and gene expression profiles were determined during 24 h of fasting followed by 8 h of feeding. Per2 and Dec1 were significantly increased within 1 h of feeding. Real-time RT-PCR analysis revealed a similarly acute response in hepatic clock gene expression caused by feeding wild type mice after an overnight fast. In addition to Per2 and Dec1, the expression of Per1 increased, and that of Rev-erbα decreased in the liver within 1 h of feeding after fasting, whereas none of these clock genes were affected in the lung. Moreover, an intraperitoneal injection of glucose combined with amino acids, but not either alone, reproduced a similar hepatic response. Our findings show that multiple clock genes respond to nutritional cues within 1 h in the liver but not in the lung.
authors: National Food Research Institute, National Agriculture and Food Research Organization, Tsukuba, Japan. oike@affrc.go.jp
authors: Hideaki
authors: H
authors: Oike
authors: Kanji
authors: K
authors: Nagai
authors: Tatsunobu
authors: T
authors: Fukushima
authors: Norio
authors: N
authors: Ishida
authors: Masuko
authors: M
authors: Kobori
mesh_terms: D000596:Amino Acids / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism; D002940:Circadian Rhythm / Q000187:drug effects / Q000235:genetics; D005247:Feeding Behavior / Q000502:physiology*; D005947:Glucose / Q000008:administration & dosage / Q000494:pharmacology; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008168:Lung; D051379:Mice; D008807:Mice, Inbred BALB C; D008817:Mice, Mutant Strains; D056953:Nuclear Receptor Subfamily 1, Group D, Member 1 / Q000235:genetics / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D056950:Period Circadian Proteins / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors
chemical_list: D000596:Amino Acids; D051792:Basic Helix-Loop-Helix Proteins; D005947:Glucose; D018398:Homeodomain Proteins; D056953:Nuclear Receptor Subfamily 1, Group D, Member 1; D056950:Period Circadian Proteins; C491539:Bhlhe40 protein, mouse; C498262:Nr1d1 protein, mouse; C539023:Per1 protein, mouse; C513312:Per2 protein, mouse