title: Effects of spaced feeding on gene expression of hepatic transaminase and gluconeogenic enzymes in rats.
abstract: Blood alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities are widely used as sensitive markers of liver toxicity. However, these activities are also recognized to be altered by hormonal and nutritional modifications. We investigated the relationships between the activity and gene expression of the hepatic transaminases and the state of hepatic amino acid/glucose/fatty acid metabolism in the ad libitum fed (ALF) and spaced-fed (SF) rats. Acceleration of hepatic gluconeogenesis and fatty acid oxidation was noted in the SF rats. Expression of hepatic clock gene was also altered in the SF rats. Hepatic transaminase activities in the SF rats were higher than those in the ALF rats. These alterations were due to increases in the synthesis of hepatic ALT and AST proteins. In conclusion, the increased transaminase protein synthesis in the liver of the SF rats was considered to be related to the acceleration of hepatic gluconeogenesis under the conditions of spaced feeding.
authors.affiliation: Toxicology Research Lab., Central Pharmaceutical Research Institute, JAPAN TOBACCO INC., 23 Naganuki Hadano, Kanagawa 257-0024, Japan. akio.kobayashi@jt.com
authors.forename: Akio
authors.initials: A
authors.lastname: Kobayashi
authors.forename: Hideaki
authors.initials: H
authors.lastname: Yokoyama
authors.forename: Jiro
authors.initials: J
authors.lastname: Kataoka
authors.forename: Tomio
authors.initials: T
authors.lastname: Ishida
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Kuno
authors.forename: Shoichiro
authors.initials: S
authors.lastname: Sugai
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Sakakibara
authors.forename: Kayoko
authors.initials: K
authors.lastname: Shimoi
mesh_terms: D000410:Alanine Transaminase / Q000097:blood / Q000235:genetics*; D000596:Amino Acids / Q000378:metabolism; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood / Q000235:genetics*; D001683:Biological Clocks / Q000235:genetics*; D005227:Fatty Acids / Q000378:metabolism; D005247:Feeding Behavior / Q000502:physiology*; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D005943:Gluconeogenesis / Q000502:physiology*; D005947:Glucose / Q000378:metabolism; D008099:Liver / Q000201:enzymology*; D051381:Rats; D013997:Time Factors
chemical_list: D000596:Amino Acids; D005227:Fatty Acids; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D005947:Glucose