title: Skeletal muscle apolipoprotein B expression reduces muscular triglyceride accumulation.
abstract: BACKGROUND
  Lipid accumulation in skeletal muscle is associated with impaired insulin sensitivity in type 2 diabetes. In cardiac myocytes, lipoprotein secretion controlled by apolipoproteinB (apoB) and microsomal triglyceride transfer protein (MTP) affects lipid homeostasis.
  
  
  METHODS
  In this study, we investigated whether expression of a human apoB transgene affects triglyceride accumulation and insulin sensitivity in skeletal muscle in fat fed obese mice.
  
  
  RESULTS
  Expression of apoB and MTP mRNA and the human apoB transgene was seen in skeletal muscle of the transgene mice. Human apoB transgenic mice accumulated 28% less triglycerides in skeletal myocytes after one year of fat-feeding as compared with WT mice (32 ± 5, n = 10 vs. 44 ± 4 nmol/mg ww, n = 13, p = 0.04). Moreover, expression of human apoB in fat-fed mice was associated with 32% (p = 0.02) and 37% (p = 0.01) lower plasma insulin levels after 9 and 12 months, respectively, improved intra peritoneal glucose tolerance after 6 months, and a trend towards increased insulin-stimulated glucose uptake in isolated skeletal muscle.
  
  
  CONCLUSIONS
  The data suggests that overexpression of apoB decreases skeletal muscle lipid accumulation and attenuates peripheral insulin resistance in obese mice.
authors.affiliation: Department of Clinical Biochemistry, Copenhagen University Hospital, Rigshospitalet , Denmark.
authors.forename: Emil D
authors.initials: ED
authors.lastname: Bartels
authors.forename: Thorkil
authors.initials: T
authors.lastname: Ploug
authors.forename: Joachim
authors.initials: J
authors.lastname: Størling
authors.forename: Thomas
authors.initials: T
authors.lastname: Mandrup-Poulsen
authors.forename: Lars B
authors.initials: LB
authors.lastname: Nielsen
mesh_terms: D000818:Animals; D001055:Apolipoproteins B / Q000235:genetics* / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance; D000078790:Insulin Secretion; D050356:Lipid Metabolism / Q000235:genetics; D008099:Liver / Q000378:metabolism; D008297:Male; D008820:Mice, Obese; D008822:Mice, Transgenic; D018482:Muscle, Skeletal / Q000502:physiology*; D009765:Obesity / Q000209:etiology / Q000378:metabolism* / Q000503:physiopathology; D010179:Pancreas / Q000378:metabolism; D014280:Triglycerides / Q000378:metabolism*
chemical_list: D001055:Apolipoproteins B; D001786:Blood Glucose; D007328:Insulin; D014280:Triglycerides
keywords: NIDDM; Obesity; apolipoprotein B; insulin resistance; skeletal muscle