title: STEAP4, a gene associated with insulin sensitivity, is regulated by several adipokines in human adipocytes.
abstract: We previously identified a six-transmembrane epithelial antigen of the prostate (STEAP) 4 as a novel plasma membrane protein that is downregulated in obese patients and may play a significant role in the development of human obesity. This study was designed to identify the biological characteristics of the STEAP4 gene in human adipocytes. On the basis of oil red O staining and the expression profiles of specific markers, we demonstrated that overexpression of STEAP4 did not affect adipogenesis. 2-Deoxy-D-[3H]-glucose uptake tests showed that STEAP4 promoted insulin-stimulated glucose uptake in mature human adipocytes. Further data from quantitative real-time RT-PCR and Western blotting revealed that the adipokines tumor necrosis factor alpha (TNFalpha), interleukin-6 (IL-6), and leptin, which have been implicated in insulin sensitivity regulation, regulate the expression of STEAP4. Our results demonstrate that STEAP4 does not influence human adipocyte differentiation, but it participates in regulating the insulin sensitivity of human adipocytes.
authors.affiliation: Department of Pediatrics, Nanjing Maternal and Child Health Hospital of Nanjing Medical University, Nanjing 210004, P.R. China.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Chen
authors.forename: Chun
authors.initials: C
authors.lastname: Zhu
authors.forename: Chenbo
authors.initials: C
authors.lastname: Ji
authors.forename: Yaping
authors.initials: Y
authors.lastname: Zhao
authors.forename: Chunmei
authors.initials: C
authors.lastname: Zhang
authors.forename: Fukun
authors.initials: F
authors.lastname: Chen
authors.forename: Chunlin
authors.initials: C
authors.lastname: Gao
authors.forename: Jingai
authors.initials: J
authors.lastname: Zhu
authors.forename: Lingmei
authors.initials: L
authors.lastname: Qian
authors.forename: Xirong
authors.initials: X
authors.lastname: Guo
mesh_terms: D017667:Adipocytes / Q000378:metabolism*; D054392:Adipokines / Q000378:metabolism*; D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D002460:Cell Line; D002648:Child; D005947:Glucose / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D007333:Insulin Resistance / Q000235:genetics; D015850:Interleukin-6 / Q000378:metabolism; D020738:Leptin / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D009765:Obesity / Q000378:metabolism / Q000503:physiopathology; D010088:Oxidoreductases / Q000235:genetics* / Q000378:metabolism*
chemical_list: D054392:Adipokines; D007328:Insulin; D015850:Interleukin-6; D020738:Leptin; D008565:Membrane Proteins; D010088:Oxidoreductases; C503310:STEAP4 protein, human; D005947:Glucose