Differential Dose Response of mTOR Signaling to Oral Administration of Leucine in Skeletal Muscle and Liver of Rats

• Published in: Bioscience, biotechnology, and biochemistry Vol. 77; no. 4; pp. 839 - 842
• Main Authors: YOSHIZAWA, Fumiaki, MOCHIZUKI, Shinji, SUGAHARA, Kunio
• Format: Journal Article
• Language: English
• Published: England Japan Society for Bioscience, Biotechnology, and Agrochemistry 2013; Oxford University Press
• Subjects: 70-kDa ribosomal protein S6 kinase (S6K1); Administration, Oral; Animals; Dose-Response Relationship, Drug; eukaryotic initiation factor 4E-binding protein 1 (4E-BP1); leucine; Leucine - administration & dosage; Leucine - pharmacology; liver; Liver - cytology; Liver - drug effects; Male; Muscle, Skeletal - cytology; Muscle, Skeletal - drug effects; Rats; Rats, Wistar; Signal Transduction - drug effects; skeletal muscle; TOR Serine-Threonine Kinases - metabolism
• ISSN: 0916-8451; 1347-6947
• DOI: 10.1271/bbb.120737

Phosphorylation of eukaryotic initiation factor 4E-binding protein 1 (4E-BP1) and 70-kDa ribosomal protein S6 kinase (S6K1) in the rat liver increased in proportion to the amount of leucine administered, ranging from 0.169 to 1.35 g/kg of body weight. In the skeletal muscle, phosphorylation of these factors reached a plateau at 0.675 g/kg of body weight. The sensitivity of mammalian target of rapamycin (mTOR) signaling to leucine in the skeletal muscle appeared to be higher than that in the liver.