title: Prevention of hyperglycemia in Zucker diabetic fatty rats by exercise training: effects on gene expression in insulin-sensitive tissues determined by high-density oligonucleotide microarray analysis.
abstract: Exercise training (ET) causes metabolic improvement in the prediabetic and diabetic states. However, only little information exists on the changes to ET at the transcriptional level in insulin-sensitive tissues. We have investigated the gene expression changes in skeletal muscle, liver, fat, and pancreatic islets after ET in male Zucker diabetic fatty (ZDF) rats. Eighteen ZDF rats (7 weeks old) were divided in a control and ET group. Exercise was performed using a motorized treadmill (20 m/min 1 hour daily for 6 days a week). Blood glucose, weight, and food intake were measured weekly. After 5 weeks, blood samples, soleus muscle, liver, visceral fat (epididymal fat pads), and islet tissue were collected. Gene expression was quantified with Affymetrix RG-U34A array (16 chips). Exercise training ameliorates the development of hyperglycemia and reduces plasma free fatty acid and the level of glucagon-insulin ratio (P < .05). In skeletal muscle, the expression of 302 genes increased, whereas that of 119 genes decreased. These changes involved genes related to skeletal muscle plasticity, Ca(2+) signals, energy metabolism (eg, glucose transporter 1, phosphorylase kinase), and other signaling pathways as well as genes with unknown functions (expressed sequence tags). In the liver, expression of 148 genes increased, whereas that of 199 genes decreased. These were primarily genes involved in lipogenesis and detoxification. Genes coding for transcription factors were changed in parallel in skeletal muscle and liver tissue. Training did not markedly influence the gene expression in islets. In conclusion, ET changes the expression of multiple genes in the soleus muscle and liver tissue and counteracts the development of diabetes, indicating that ET-induced changes in gene transcription may play an important role en the prevention of diabetes.
authors.affiliation: Department of Endocrinology and Metabolism C, Aarhus Sygehus THG, Aarhus University Hospital, Tage Hansens Gade 2, Aarhus, Denmark. michele.colombo@ki.au.dk
authors.forename: Michele
authors.initials: M
authors.lastname: Colombo
authors.forename: Soeren
authors.initials: S
authors.lastname: Gregersen
authors.forename: Mogens
authors.initials: M
authors.lastname: Kruhoeffer
authors.forename: Andreas
authors.initials: A
authors.lastname: Agger
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Xiao
authors.forename: Per Bendix
authors.initials: PB
authors.lastname: Jeppesen
authors.forename: Torben
authors.initials: T
authors.lastname: Orntoft
authors.forename: Thorkil
authors.initials: T
authors.lastname: Ploug
authors.forename: Henrik
authors.initials: H
authors.lastname: Galbo
authors.forename: Kjeld
authors.initials: K
authors.lastname: Hermansen
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D003924:Diabetes Mellitus, Type 2 / Q000517:prevention & control*; D020869:Gene Expression Profiling; D006943:Hyperglycemia / Q000517:prevention & control*; D007515:Islets of Langerhans / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010805:Physical Conditioning, Animal; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D011924:Rats, Zucker; D015398:Signal Transduction; D014781:Viscera / Q000378:metabolism
chemical_list: D001786:Blood Glucose; D012333:RNA, Messenger