title: Feeding period restriction alters the expression of peripheral circadian rhythm genes without changing body weight in mice.
abstract: Accumulating evidence suggests that the circadian clock is closely associated with metabolic regulation. However, whether an impaired circadian clock is a direct cause of metabolic dysregulation such as body weight gain is not clearly understood. In this study, we demonstrate that body weight gain in mice is not significantly changed by restricting feeding period to daytime or nighttime. The expression of peripheral circadian clock genes was altered by feeding period restriction, while the expression of light-regulated hypothalamic circadian clock genes was unaffected by either a normal chow diet (NCD) or a high-fat diet (HFD). In the liver, the expression pattern of circadian clock genes, including Bmal1, Clock, and Per2, was changed by different feeding period restrictions. Moreover, the expression of lipogenic genes, gluconeogenic genes, and fatty acid oxidation-related genes in the liver was also altered by feeding period restriction. Given that feeding period restriction does not affect body weight gain with a NCD or HFD, it is likely that the amount of food consumed might be a crucial factor in determining body weight. Collectively, these data suggest that feeding period restriction modulates the expression of peripheral circadian clock genes, which is uncoupled from light-sensitive hypothalamic circadian clock genes.
authors.affiliation: School of Biological Sciences, Institute of Molecular Biology and Genetics, Center for Adipose Tissue Remodeling, Seoul National University, Seoul, Korea.
authors.forename: Hagoon
authors.initials: H
authors.lastname: Jang
authors.forename: Gung
authors.initials: G
authors.lastname: Lee
authors.forename: Jinuk
authors.initials: J
authors.lastname: Kong
authors.forename: Goun
authors.initials: G
authors.lastname: Choi
authors.forename: Yoon Jeong
authors.initials: YJ
authors.lastname: Park
authors.forename: Jae Bum
authors.initials: JB
authors.lastname: Kim
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001835:Body Weight / Q000502:physiology*; D002784:Cholesterol / Q000097:blood; D002940:Circadian Rhythm / Q000235:genetics* / Q000502:physiology; D056925:Circadian Rhythm Signaling Peptides and Proteins / Q000378:metabolism*; D017931:DNA Primers / Q000235:genetics; D059305:Diet, High-Fat; D005248:Feeding Methods; D005786:Gene Expression Regulation / Q000235:genetics / Q000502:physiology*; D007031:Hypothalamus / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D060888:Real-Time Polymerase Chain Reaction; D013997:Time Factors; D014280:Triglycerides / Q000097:blood
chemical_list: D056925:Circadian Rhythm Signaling Peptides and Proteins; D017931:DNA Primers; D014280:Triglycerides; D002784:Cholesterol