ABSTRACT
OBJECTIVE: To observe whether and how N-myc downstream-regulated gene 1 (NDRG1) regulates placental angiogenesis via JEG-3 placental-derived cells. METHODS: Expression of NDRG1 in stably transfected JEG-3 cells was detected using western blot and real-time quantitative polymerase chain reaction. Angiogenesis was examined by tube formation assay. The levels of placental growth factor (PLGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) were examined using enzyme-linked immunosorbent assay. The expression of vascular endothelial growth factor (VEGF), PI3K, and AKT was examined by western blot. The relationship between PI3K and NDRG1 was detected by co-immunoprecipitation. RESULTS: NDRG1 was significantly down-regulated at both the mRNA and protein level by lentivirus (Lv)-NDRG1-shRNA (P < 0.001), whereas it was significantly up-regulated by Lv-NDRG1 (P < 0.001). NDRG1 knockdown significantly increase the expression of PLGF and VEGF in JEG-3 cells (P < 0.001), while NDRG1 knockdown significantly reduced the secretion of sFlt-1 (P < 0.001). NDRG1 was specific bound to PI3K, and NDRG1 knockdown significantly up-regulated the expressions of PI3K and AKT in JEG-3 cells (P < 0.001). CONCLUSION: NDRG1 suppresses angiogenesis in preeclampsia, and the PI3K/AKT signaling pathway may be involved in the regulation of angiogenesis by NDRG1.
Subject(s)
Cell Cycle Proteins/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Placenta/metabolism , Pre-Eclampsia/genetics , Angiogenesis Inhibitors/metabolism , Down-Regulation , Female , Gene Knockdown Techniques , Humans , Phosphatidylinositol 3-Kinases/metabolism , Pregnancy , Signal TransductionABSTRACT
OBJECTIVES: The purpose of this study was to investigate the expression of Filamin b in the placental placenta of patients with early or late onset pre-eclampsia (PE) and its potential effects on the pathophysiology of the disease. METHODS AND METHODS: Immunohistochemistry staining, western blot assays and real time PCR were used to detect the expression level of FLN-b. The expression levels of MMP-2, MMP-9 and ERK1/2 proteins from control and FLN-b-silenced JEG-3 cells were also detected by western blot and JEG-3 cell invasion. RESULTS: Compared with normal term pregnancies placentas, the FLN-b expression was significantly lower than that of women with PE, its level in late-onset PE is lower than in early-onset PE. In FLN-b-silenced JEG-3 cells, the protein levels of MMP-2, MMP-9 and phosphorylated ERK1/2 decreased markedly and the number of cells penetrating through the transwell chamber membrane is also greatly reduced. CONCLUSIONS: Down-regulation of FLN-b inhibits the ERK/MMP-2 and MMP-9 pathways, leading to trophoblastic invasion disorders in the PE placenta.
Subject(s)
Filamins/metabolism , MAP Kinase Signaling System/physiology , Matrix Metalloproteinase 9/metabolism , Placenta , Pre-Eclampsia/metabolism , Adult , Cell Line, Tumor , Female , Filamins/analysis , Filamins/genetics , Humans , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Placenta/chemistry , Placenta/cytology , Placenta/metabolism , Pregnancy , Trophoblasts/cytology , Young AdultABSTRACT
OBJECTIVE: The aim of this study was to investigate the expression of N-myc downstream-regulated gene1(NDRG1)in the placentas of pregnancies complicated with early-onset and late-onset preeclampsia (PE) and its underlying mechanism on the pathophysiology of PE. METHODS: The expressions of NDRG-1 in placentas of pregnancies complicated with early-onset PE and late-onset PE were detected using immunohistochemistry, western blot assays and fluorescence quantitative PCR. The expressions of MMP-2, MMP-9 and ERK1/2 protein were detected by western blot analysis and cell invasion assay was performed using transwell chambers in NDRG1 silenced JEG-3 cells. RESULTS: Compared with the normal term pregnancies, the expression of both NDRG1 mRNA and protein were significantly high in placentas from PE, and the expression of NDRG1 in early-onset PE was higher than that in late-onset PE. In NDRG1-silenced JEG-3 cells, MMP-2, MMP-9 and phosphorylation of ERK1/2 protein increased obviously and the number of cells that penetrated the membrane increased. CONCLUSION: Upregulation of NDRG1 is associated with impaired trophoblast invasion in PE by inhibition ERK/MMP-2 and MMP-9 Pathway.
Subject(s)
Cell Cycle Proteins/metabolism , Cell Movement/physiology , Intracellular Signaling Peptides and Proteins/metabolism , MAP Kinase Signaling System/physiology , Matrix Metalloproteinase 9/metabolism , Pre-Eclampsia/metabolism , Trophoblasts/metabolism , Up-Regulation , Cell Cycle Proteins/genetics , Cell Line , Female , Gene Silencing , Humans , Intracellular Signaling Peptides and Proteins/genetics , Matrix Metalloproteinase 2/genetics , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/genetics , Phosphorylation , Placenta/metabolism , Placenta/pathology , Pre-Eclampsia/genetics , Pre-Eclampsia/pathology , Pregnancy , Trophoblasts/pathologyABSTRACT
This paper presents an intelligent system allowing handicapped aphasiacs to perform basic communication tasks. It has the following three key features: (1) A 6-sensor data glove measures the finger gestures of a patient in terms of the bending degrees of his fingers. (2) A finger language recognition subsystem recognizes language components from the finger gestures. It employs multiple regression analysis to automatically extract proper finger features so that the recognition model can be fast and correctly constructed by a radial basis function neural network. (3) A coordinate-indexed virtual keyboard allows the users to directly access the letters on the keyboard at a practical speed. The system serves as a viable tool for natural and affordable communication for handicapped aphasiacs through continuous finger language input.
