title: Effects of diet and exercise on muscle and liver intracellular lipid contents and insulin sensitivity in type 2 diabetic patients.
abstract: Insulin resistance is associated with the circulating free fatty acid (FFA) level and intracellular lipid content in muscle and liver. We investigated the effect of 2-wk diet and exercise therapy on total adiposity, circulating FFA, intracellular lipid content in muscle and liver, and peripheral insulin sensitivity. Type 2 diabetic patients were divided into a diet group (n = 7) and a diet plus exercise group (n = 7). We performed a hyperinsulinemic-euglycemic clamp study before and after treatment. Intramyocellular lipid (IMCL) in the tibialis anterior muscle and intrahepatic lipid (IHL) were evaluated by (1)H-magnetic resonance spectroscopy. Fasting FFA were not altered, and total body fat showed a slight, but significant, decrease in both groups after treatment. IMCL was decreased by 19%, and the glucose infusion rate was increased by 57% in the diet plus exercise group, whereas neither IMCL nor glucose infusion rate was significantly altered in the diet group. However, IHL showed a significant decrease in both groups. In summary, we found that 2 wk of diet and exercise decreased IMCL and increased muscle insulin-mediated glucose uptake, whereas diet with or without exercise decreased IHL. These effects were evident despite a small decrease in body fat and were observed independently of fasting FFA levels.
authors.affiliation: Department of Medicine, Metabolism and Endocrinology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Tamura
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Sato
authors.forename: Jong Bock
authors.initials: JB
authors.lastname: Choi
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Watada
authors.forename: Masataka
authors.initials: M
authors.lastname: Niwa
authors.forename: Junichiro
authors.initials: J
authors.lastname: Kinoshita
authors.forename: Aiko
authors.initials: A
authors.lastname: Ooka
authors.forename: Naoki
authors.initials: N
authors.lastname: Kumashiro
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Igarashi
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Kyogoku
authors.forename: Tadayuki
authors.initials: T
authors.lastname: Maehara
authors.forename: Masahiko
authors.initials: M
authors.lastname: Kawasumi
authors.forename: Takahisa
authors.initials: T
authors.lastname: Hirose
authors.forename: Ryuzo
authors.initials: R
authors.lastname: Kawamori
mesh_terms: D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism; D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism / Q000503:physiopathology*; D003927:Diet, Diabetic; D015444:Exercise / Q000502:physiology*; D005260:Female; D015309:Glucose Clamp Technique; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D006946:Hyperinsulinism / Q000097:blood; D007328:Insulin / Q000494:pharmacology / Q000600:supply & distribution; D050356:Lipid Metabolism; D008099:Liver / Q000378:metabolism*; D008111:Liver Function Tests; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism*
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007328:Insulin