title: Beneficial effect of galanin on insulin sensitivity in muscle of type 2 diabetic rats.
abstract: The aim of this study was to determine whether enhanced galanin (GAL) release induced by exercise would elevate insulin sensitivity and glucose transporter 4 (GLUT4) concentration in the plasma membranes of skeletal muscle in type 2 diabetic rats. We used M35, a GAL antagonist to antagonize the GAL function and swimming training for four weeks to increase GAL release of rats. The blood samples were analyzed for GAL and insulin concentration. The euglycemic-hyperinsulinemic clamp test was conducted for an index of glucose infusion rates. Additionally, skeletal muscle was collected and processed for GLUT4 mRNA level and GLUT4 concentration. The present findings showed that plasma GAL levels after swimming training in all three trained groups were higher compared with each sedentary control and each preswimming level. The insulin levels after swimming in both M35 treatment groups were elevated compared with each diabetic control and each pretraining level. Moreover, M35 treatment reduced glucose infusion rates compared with each diabetic control, but swimming enhanced the rates in all trained groups compared with each sedentary control. Furthermore, M35 treatment reduced GLUT4 concentration and GLUT4 mRNA levels compared with each diabetic control. The ratio of GLUT4 contents in plasma membranes to total cell membranes in both drug groups were lower compared with each diabetic control. These results suggest that endogenous GAL may enhance GLUT4 contents and promote GLUT4 transportation from intracellular membrane pools to plasma membranes. GAL is an important hormone to regulate insulin sensitivity in skeletal muscle from type 2 diabetic rats.
authors.affiliation: Department of Physical Education, Anhui Defence Vacation College, Luan, Anhui Province, 237011, PR China.
authors.forename: Biao
authors.initials: B
authors.lastname: He
authors.forename: Mingyi
authors.initials: M
authors.lastname: Shi
authors.forename: Ling
authors.initials: L
authors.lastname: Zhang
authors.forename: Guangzhi
authors.initials: G
authors.lastname: Li
authors.forename: Lingxiang
authors.initials: L
authors.lastname: Zhang
authors.forename: Hu
authors.initials: H
authors.lastname: Shao
authors.forename: Jian
authors.initials: J
authors.lastname: Li
authors.forename: Penghua
authors.initials: P
authors.lastname: Fang
authors.forename: Yinping
authors.initials: Y
authors.lastname: Ma
authors.forename: Qiaojia
authors.initials: Q
authors.lastname: Shi
authors.forename: Yumei
authors.initials: Y
authors.lastname: Sui
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001786:Blood Glucose; D001920:Bradykinin / Q000031:analogs & derivatives / Q000627:therapeutic use; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy / Q000209:etiology / Q000473:pathology* / Q000534:rehabilitation; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D019004:Galanin / Q000097:blood* / Q000627:therapeutic use; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology; D015309:Glucose Clamp Technique / Q000379:methods; D051275:Glucose Transporter Type 4 / Q000097:blood / Q000235:genetics; D007328:Insulin / Q000378:metabolism*; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000473:pathology; D010446:Peptide Fragments / Q000627:therapeutic use; D010805:Physical Conditioning, Animal / Q000379:methods; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013311:Streptozocin / Q000633:toxicity; D013550:Swimming
chemical_list: D001786:Blood Glucose; D051275:Glucose Transporter Type 4; D007328:Insulin; D010446:Peptide Fragments; D012333:RNA, Messenger; C495694:Slc2a4 protein, rat; C074069:galanin-(1-13)-bradykinin-(2-9)-amide; D013311:Streptozocin; D019004:Galanin; D001920:Bradykinin