title: Regular feeding plays an important role in cholesterol homeostasis through the liver circadian clock.
abstract: BACKGROUND
  Peripheral clock control and the relevance of the circadian rhythm to physiology and disease are major questions in mammalian circadian biology.
  
  
  OBJECTIVE
  We examined the physiological functions of the liver clock.
  
  
  RESULTS
  We established a suppressed feeding schedule regimen constituting a high-cholesterol diet delivered every 6 hours without changes in energy and cholesterol intake. We found that rats exposed to this regimen developed hypercholesteremia. In the liver, the rhythmicity of expression of several clock genes was disrupted. Furthermore, the nocturnal expression of the CYP7A1 gene, which encodes the rate-limiting enzyme for the conversion of cholesterol to bile acids, was shifted to a diurnal pattern. Indeed, suppression of a regular feeding rhythm increased the secretion rate of very-low-density lipoprotein cholesterol from the liver and decreased the excretion of fecal bile acids.
  
  
  CONCLUSIONS
  Our results demonstrated that not only the amount and quality of food but also the timing of meals has crucial health implications.
authors: Department of Applied Molecular Biosciences, Laboratory of Nutritional Biochemistry, Nagoya University, Nagoya 464-8601, Japan.
authors: Daisuke
authors: D
authors: Yamajuku
authors: Shingo
authors: S
authors: Okubo
authors: Tomonori
authors: T
authors: Haruma
authors: Takahiko
authors: T
authors: Inagaki
authors: Yuji
authors: Y
authors: Okuda
authors: Tomoko
authors: T
authors: Kojima
authors: Keiji
authors: K
authors: Noutomi
authors: Seiichi
authors: S
authors: Hashimoto
authors: Hiroaki
authors: H
authors: Oda
mesh_terms: D000818:Animals; D001647:Bile Acids and Salts / Q000378:metabolism; D015243:Cholesterol, VLDL / Q000378:metabolism*; D002940:Circadian Rhythm; D004036:Diet, Atherogenic; D005248:Feeding Methods; D006706:Homeostasis; D008099:Liver / Q000201:enzymology* / Q000378:metabolism; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013254:Steroid 17-alpha-Hydroxylase / Q000378:metabolism*
chemical_list: D001647:Bile Acids and Salts; D015243:Cholesterol, VLDL; D013254:Steroid 17-alpha-Hydroxylase