title: ALK7 expression is specific for adipose tissue, reduced in obesity and correlates to factors implicated in metabolic disease.
abstract: Human adipose tissue is a major site of expression of inhibin beta B (INHBB) which homodimerizes to form the novel adipokine activin B. Our aim was to determine if molecules needed for a local action of activin B are expressed in adipose tissue. Microarray analysis showed that adipose tissue expressed activin type I and II receptors and that the expression of activin receptor-like kinase 7 (ALK7) was adipose tissue specific. In obesity discordant siblings from the SOS Sib Pair study, adipose tissue ALK7 expression was higher in lean (n=90) compared to obese (n=90) subjects (p=4 x 10(-31)). Adipose tissue ALK7 expression correlated with several measures of body fat, carbohydrate metabolism and lipids. In addition, ALK7 and INHBB expression correlated but only in lean subjects and in subjects with normal glucose tolerance. We conclude that activin B may have local effects in adipose tissue and thereby influence obesity and its comorbidities.
authors.affiliation: Department of Molecular and Clinical Medicine and Center for Cardiovascular and Metabolic Research, The Sahlgrenska Academy, Göteborg, Sweden.
authors.forename: Lena M S
authors.initials: LM
authors.lastname: Carlsson
authors.forename: Peter
authors.initials: P
authors.lastname: Jacobson
authors.forename: Andrew
authors.initials: A
authors.lastname: Walley
authors.forename: Philippe
authors.initials: P
authors.lastname: Froguel
authors.forename: Lars
authors.initials: L
authors.lastname: Sjöström
authors.forename: Per-Arne
authors.initials: PA
authors.lastname: Svensson
authors.forename: Kajsa
authors.initials: K
authors.lastname: Sjöholm
mesh_terms: D030201:Activin Receptors, Type I / Q000235:genetics*; D030301:Activin Receptors, Type II / Q000235:genetics; D000273:Adipose Tissue / Q000201:enzymology*; D020869:Gene Expression Profiling; D006801:Humans; D028322:Inhibin-beta Subunits / Q000235:genetics; D009765:Obesity / Q000201:enzymology*; D020411:Oligonucleotide Array Sequence Analysis; D021122:Protein Subunits / Q000235:genetics; D014018:Tissue Distribution
chemical_list: C422402:INHBB protein, human; D021122:Protein Subunits; D028322:Inhibin-beta Subunits; C425423:ACVR1 protein, human; C424205:ACVR1C protein, human; D030201:Activin Receptors, Type I; D030301:Activin Receptors, Type II; C425585:activin receptor type II-A