Background: Protein tyrosine phosphatase 1B (PTPN1) dephosphorylates insulin receptors and attenuates insulin signaling. Polymorphisms in the coding sequence of PTPN1 have been variably associated with type 2 diabetes (T2D). We hypothesized that variations within the PTPN1 promoter might contribute to the development of T2D and related metabolic traits.
Methods: We screened 2.0 kb of PTPN1 promoter in 174 T2D patients and 412 controls using PCR and denaturing HPLC. Association analysis was performed between diabetes and related traits and single-nucleotide polymorphism genotypes. We functionally tested 2 variants (-1023C>A and -51delA) by measuring their influence on luciferase activity in HepG2 cells and performing the electrophoretic mobility shift assay (EMSA).
Results: One common (-1023C>A) and 6 rare (-51delA, -451A>G, -467T>C, -1045G>A, -1286-3bp-del, and -1291-9bp-del) variants were identified in the PTPN1 promoter. The -1023(C) allele had significant association with T2D that disappeared after we adjusted for established diabetes risk factors. The alleles of -1023C>A and -51delA variants did not show significant effects on the biochemical markers after adjustment for established diabetes risk factors in the nondiabetic and diabetic groups separately. The -51delA variant decreased luciferase gene expression in HepG2 cells by 2-fold. EMSA revealed a weaker binding of -51delA to specific protein family proteins compared with the A allele. The -1023C>A variant had no influence in either experiment.
Conclusions: The PTPN1 promoter variants -1023C>A and -51delA (which appears to be functional) were not associated with T2D or related traits in this study but must be investigated in a larger population to reveal any potential metabolic association.
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http://dx.doi.org/10.1373/clinchem.2007.088146 | DOI Listing |
Int Immunopharmacol
January 2024
Department of Pathophysiology, School of Basic Medical Science, Central South University, 110 Xiangya Road, Changsha 410083, China; Key Laboratory of Sepsis Translational Medicine of Hunan, Central South University, 110 Xiangya Road, Changsha 410083, China. Electronic address:
Objectives: To investigate the role of protein tyrosine phosphatase non-receptor type 1 (PTPN1) in mitophagy during sepsis and its underlying mechanisms and determine the therapeutic potential of PTPN1 inhibitors in endotoxemia-induced cardiac dysfunction.
Methods: A mouse model of endotoxemia was established by administering an intraperitoneal injection of lipopolysaccharide (LPS). The therapeutic effect of targeting PTPN1 was evaluated using its inhibitor Claramine (CLA).
Thromb Haemost
October 2022
Department of Cardiology, Cardiology I, University Medical Center Mainz, Mainz, Germany.
Background: Smooth muscle cell (SMC) phenotype switching plays a central role during vascular remodeling. Growth factor receptors are negatively regulated by protein tyrosine phosphatases (PTPs), including its prototype PTP1B. Here, we examine how reduction of PTP1B in SMCs affects the vascular remodeling response to injury.
View Article and Find Full Text PDFActa Biochim Biophys Sin (Shanghai)
April 2022
Department of Anesthesiology, the Third Hospital, Affiliated to the Xinjiang Medical University, Urumqi 830011, China.
Hyperglycemia-induced endothelial inflammation participates in the pathogenesis of cardiovascular complications in diabetics. Previous studies showed that protein tyrosine phosphatase 1B (PTP1B) and ETS proto-oncogene 1 (ets1) are involved in hyperglycemia-induced endothelial inflammation. In this study, we hypothesized that ets1 modulates PTP1B expression, thus playing a crucial role in hyperglycemia-induced vascular endothelial inflammation.
View Article and Find Full Text PDFNan Fang Yi Ke Da Xue Xue Bao
March 2022
Chongqing Key Laboratory of Lipid and Glucose Metabolism, Center for Lipid Research, Chongqing Medical University, Chongqing 400016, China.
Objective: To investigate the effect CD36 deficiency on muscle insulin signaling in mice fed a normal-fat diet and explore the possible mechanism.
Methods: Wild-type (WT) mice and systemic CD36 knockout (CD36) mice with normal feeding for 14 weeks (=12) were subjected to insulin tolerance test (ITT) after intraperitoneal injection with insulin (1 U/kg). Real-time PCR was used to detect the mRNA expressions of insulin receptor (IR), insulin receptor substrate 1/2 (IRS1/2) and protein tyrosine phosphatase 1B (PTP1B), and Western blotting was performed to detect the protein expressions of AKT, IR, IRS1/2 and PTP1B in the muscle tissues of the mice.
Curr Cancer Drug Targets
June 2022
Hefei Visionnox Technology Co., Ltd, Hefei 230012, China.
In vivo, tyrosine phosphorylation is a reversible and dynamic process governed by the opposing activities of protein tyrosine kinases and phosphatases. Defective or inappropriate operation of these proteins leads to aberrant tyrosine phosphorylation, which contributes to the development of many human diseases, including cancers. PTP1B, a non-transmembrane phosphatase, is generally considered a negative regulator of the metabolic signaling pathways and a promising drug target for type II diabetes and obesity.
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