title: Constant expression of hexose-6-phosphate dehydrogenase during differentiation of human adipose-derived mesenchymal stem cells.
abstract: The reductase activity of 11beta-hydroxysteroid dehydrogenase type 1 (HSD11B1) plays an important role in the growth and differentiation of adipose tissue via the prereceptorial activation of glucocorticoids. This enzyme colocalizes with hexose-6-phosphate dehydrogenase (H6PD) at the luminal surface of the endoplasmic reticulum membrane, and the latter enzyme provides NADPH to the former, which can thus act as an 11beta-reductase. It was suggested that, during adipogenesis, the increased expression of H6PD causes a dehydrogenase-to-reductase switch in the activity of HSD11B1. However, only the expression of the HSD11B1 has been extensively studied, and little is known about the expression of H6PD. Here, we investigated the expression and the activity of H6PD in the course of the differentiation of human adipose-derived mesenchymal stem cells (ADMSCs) and murine 3T3-L1 cells. It was found that H6PD is already present in adipose-derived stem cells and in 3T3-L1 fibroblasts even before the induction of adipogenesis. Moreover, mRNA and protein levels, as well as the microsomal H6PD activities remained unchanged during the differentiation. At the same time a great induction of HSD11B1 was observed in both cell types. The observed constant expression of H6PD suggests that HSD11B1 acts as a reductase throughout the adipogenesis process in human ADMSCs and murine 3T3-L1 cells.
authors.affiliation: Department of Pathophysiology, Experimental Medicine and Public Health, University of Siena, Via A. Moro no. 1, 53100 Siena, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Senesi
authors.forename: Paola
authors.initials: P
authors.lastname: Marcolongo
authors.forename: Ivana
authors.initials: I
authors.lastname: Manini
authors.forename: Rosella
authors.initials: R
authors.lastname: Fulceri
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Sorrentino
authors.forename: Miklós
authors.initials: M
authors.lastname: Csala
authors.forename: Gábor
authors.initials: G
authors.lastname: Bánhegyi
authors.forename: Angelo
authors.initials: A
authors.lastname: Benedetti
mesh_terms: D043205:11-beta-Hydroxysteroid Dehydrogenase Type 1 / Q000096:biosynthesis / Q000235:genetics; D041721:3T3-L1 Cells; D050156:Adipogenesis; D000273:Adipose Tissue / Q000166:cytology* / Q000201:enzymology*; D000818:Animals; D002237:Carbohydrate Dehydrogenases / Q000096:biosynthesis / Q000235:genetics*; D002454:Cell Differentiation; D019070:Cell Lineage; D003348:Cortisone / Q000378:metabolism; D003349:Cortisone Reductase / Q000378:metabolism; D004790:Enzyme Induction; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000201:enzymology*; D051379:Mice; D010084:Oxidation-Reduction; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D012333:RNA, Messenger; D002237:Carbohydrate Dehydrogenases; C020552:galactose-6-phosphate dehydrogenase; D043205:11-beta-Hydroxysteroid Dehydrogenase Type 1; D003349:Cortisone Reductase; D003348:Cortisone; D006854:Hydrocortisone