Corticotropin-releasing hormone system in human adipose tissue.
Mounting evidence exists for a role of the CRH system in energy balance, including a direct influence on human adipocytes, the regulation of adipose 11 beta-hydroxysteroid dehydrogenase type 1 activity, and cortisol formation. We characterized the expression of CRH receptors 1 and 2 and CRH-like peptides stresscopin and urocortin in human adipose tissue in comparison with other peripheral tissues, adrenal, and heart. The effect of CRH on CRH receptor and CRH-like peptide expression was analyzed in isolated human adipocytes using quantitative TaqMan PCR. CRH receptors were detectable in fat tissue at mRNA and protein levels. CRH-R2 expression in fat was comparable with its expression in the heart, the organ with the highest CRH-R2 expression known. CRH-R1:CRH-R2 ratio varied according to fat-depot type; whereas CRH-R1 expression was higher in sc fat than in visceral fat, the opposite was true for CRH-R2. Adipose tissue also expressed urocortin and stresscopin, the predominant ligands of peripheral CRH-R2. CRH down-regulated CRH-R1 and CRH-R2 mRNA expression in isolated adipocytes. These data, together with the recently published observation that CRH regulates adipocyte metabolism by down-regulating 11 beta-hydroxysteroid dehydrogenase, indicate that a CRH system exists within human adipose tissue. This system could be implicated in energy homeostasis and in mediating the anorexic effects of CRH at adipose level.
Seres
Janette
J
German Diabetes Center, Heinrich Heine University of Duesseldorf, Duesseldorf 65 40225, Germany.
Bornstein
Stefan R
SR
Seres
Peter
P
Willenberg
Holger S
HS
Schulte
Klaus M
KM
Scherbaum
Werner A
WA
Ehrhart-Bornstein
Monika
M
D000273:Adipose Tissue / Q000187:drug effects / Q000378:metabolism*; D000311:Adrenal Glands / Q000378:metabolism; D000328:Adult; D002478:Cells, Cultured; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism* / Q000494:pharmacology; D015536:Down-Regulation; D005260:Female; D006801:Humans; D009206:Myocardium / Q000378:metabolism; D018019:Receptors, Corticotropin-Releasing Hormone / Q000378:metabolism*; D040521:Subcutaneous Tissue; D014018:Tissue Distribution; D054832:Urocortins; D014781:Viscera; D000099052:CRF Receptor, Type 1
C101531:CRF receptor type 2; D018019:Receptors, Corticotropin-Releasing Hormone; C426704:UCN3 protein, human; D054832:Urocortins; D000099052:CRF Receptor, Type 1; D003346:Corticotropin-Releasing Hormone