Topiramate treatment causes skeletal muscle insulin sensitization and increased Acrp30 secretion in high-fat-fed male Wistar rats.
We show that Topiramate (TPM) treatment normalizes whole body insulin sensitivity in high-fat diet (HFD)-fed male Wistar rats. Thus drug treatment markedly lowered glucose and insulin levels during glucose tolerance tests and caused increased insulin sensitization in adipose and muscle tissues as assessed by euglycemic clamp studies. The insulin-stimulated glucose disposal rate increased twofold (indicating enhanced muscle insulin sensitivity), and suppression of circulating FFAs increased by 200 to 300%, consistent with increased adipose tissue insulin sensitivity. There were no effects of TPM on hepatic insulin sensitivity in these TPM-treated HFD-fed rats. In addition, TPM administration resulted in a three- to fourfold increase in circulating levels of total and high-molecular-weight (HMW) adiponectin (Acrp30). Western blot analysis revealed normal AMPK (Thr(172)) phosphorylation in liver with a twofold increased phospho-AMPK in skeletal muscle in TPM-treated rats. In conclusion, 1) TPM treatment prevents overall insulin resistance in HFD male Wistar rats; 2) drug treatment improved insulin sensitivity in skeletal muscle and adipose tissue associated with enhanced AMPK phosphorylation; and 3) the tissue "specific" effects are associated with increased serum levels of adiponectin, particularly the HMW component.
Wilkes
Jason J
JJ
Division of Endocrinology and Metabolism, Department of Medicine, University of California-San Diego, 0673 UCSD, 9500 Gilman Drive, La Jolla, CA 92093, USA. jwilkes@gnf.org
Nguyen
M T Audrey
MT
Bandyopadhyay
Gautam K
GK
Nelson
Elizabeth
E
Olefsky
Jerrold M
JM
D055372:AMP-Activated Protein Kinases; D052242:Adiponectin / Q000097:blood / Q000378:metabolism; D000273:Adipose Tissue / Q000187:drug effects; D000818:Animals; D019440:Anti-Obesity Agents / Q000008:administration & dosage*; D001786:Blood Glucose / Q000032:analysis; D004041:Dietary Fats / Q000008:administration & dosage*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005632:Fructose / Q000008:administration & dosage / Q000031:analogs & derivatives*; D015309:Glucose Clamp Technique; D007328:Insulin / Q000097:blood / Q000494:pharmacology*; D007333:Insulin Resistance; D008099:Liver / Q000201:enzymology; D008297:Male; D009097:Multienzyme Complexes / Q000378:metabolism; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000502:physiology; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D000077236:Topiramate
D052242:Adiponectin; C499920:Adipoq protein, rat; D019440:Anti-Obesity Agents; D001786:Blood Glucose; D004041:Dietary Fats; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D009097:Multienzyme Complexes; D000077236:Topiramate; D005632:Fructose; D017346:Protein Serine-Threonine Kinases; D055372:AMP-Activated Protein Kinases