Department of Pediatrics, Nanjing Maternal and Child Health Hospital of Nanjing Medical University, Nanjing 210004, P.R. China.
Int J Mol Med. 2010 Mar;25(3):361-7. doi: 10.3892/ijmm_00000353.
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.
我们之前鉴定了六跨膜上皮抗原的前列腺（STEAP）4 作为一种新型的质膜蛋白，在肥胖患者下调，可能在人类肥胖的发展中发挥重要作用。本研究旨在鉴定人类脂肪细胞中 STEAP4 基因的生物学特性。根据油红 O 染色和特定标记物的表达谱，我们证明 STEAP4 的过表达并不影响脂肪生成。2-脱氧-D-[3H]-葡萄糖摄取试验表明，STEAP4 促进成熟人脂肪细胞中胰岛素刺激的葡萄糖摄取。来自定量实时 RT-PCR 和 Western blot 的进一步数据表明，脂肪细胞因子肿瘤坏死因子 α（TNFalpha）、白细胞介素-6（IL-6）和瘦素，它们与胰岛素敏感性调节有关，调节 STEAP4 的表达。我们的结果表明，STEAP4 不影响人类脂肪细胞分化，但它参与调节人类脂肪细胞的胰岛素敏感性。
