title: Brown adipocyte progenitor population is modified in obese and diabetic skeletal muscle.
abstract: Brown adipose tissue mitochondria express the unique thermogenic uncoupling protein-1. Recently, brown adipocyte progenitors have been identified in the CD34+ cell population of human skeletal muscle. The aims of this study were firstly to determine if obesity and diabetes have altered amounts of muscle brown adipocyte progenitors and, secondly, to establish if the latter are correlated with clinical parameters of obesity and diabetes. Body mass index (BMI), plasma glucose, insulin, cholesterol and triglycerides as well as homeostasis model assessment were measured in lean (n=10), obese (n=18) and obese-diabetic (n=15) subjects and muscle biopsies were taken from the rectus abdominus. CD34 being also expressed on endothelial cells, we measured CD31, another endothelial marker, and expressed the brown adipocyte progenitors, as the CD34/CD31 mRNA ratio. The latter was significantly reduced in the obese vs lean subjects suggesting a smaller pool of brown adipocyte progenitors. More strikingly, for lean and obese subjects negative correlations were observed between the CD34/CD31 mRNA ratios and BMI, fasting insulin levels and homeostasis model assessment. These correlations highlight the potential physiological relevance of the muscle CD34/CD31 mRNA ratio.
authors.affiliation: School of Exercise and Nutrition Sciences, Deakin University, Burwood, New South Wales, Australia.
authors.forename: A P
authors.initials: AP
authors.lastname: Russell
authors.forename: M
authors.initials: M
authors.lastname: Crisan
authors.forename: B
authors.initials: B
authors.lastname: Léger
authors.forename: M
authors.initials: M
authors.lastname: Corselli
authors.forename: A J
authors.initials: AJ
authors.lastname: McAinch
authors.forename: P E
authors.initials: PE
authors.lastname: O'Brien
authors.forename: D
authors.initials: D
authors.lastname: Cameron-Smith
authors.forename: B
authors.initials: B
authors.lastname: Péault
authors.forename: L
authors.initials: L
authors.lastname: Casteilla
authors.forename: J-P
authors.initials: JP
authors.lastname: Giacobino
mesh_terms: D052437:Adipocytes, Brown / Q000378:metabolism*; D000328:Adult; D018952:Antigens, CD34 / Q000235:genetics / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D002784:Cholesterol / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000000981:diagnostic imaging / Q000378:metabolism*; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000378:metabolism*; D009765:Obesity / Q000000981:diagnostic imaging / Q000235:genetics / Q000378:metabolism*; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000235:genetics / Q000378:metabolism; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000378:metabolism; D011877:Radionuclide Imaging; D013234:Stem Cells / Q000378:metabolism*; D013851:Thinness / Q000378:metabolism*; D014280:Triglycerides / Q000097:blood
chemical_list: D018952:Antigens, CD34; D001786:Blood Glucose; D007328:Insulin; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D012333:RNA, Messenger; D014280:Triglycerides; D002784:Cholesterol