Altered expression of plasminogen activator inhibitor type-1 (PAI-1), a major physiologic inhibitor of fibrinolysis, is implicated in the progression of atherosclerosis. Sphingosine 1-phosphate (S1P) regulates expression of diverse genes and alters expression of PAI-1 in several types of cells. However, the nature of posttranscriptional regulation of expression of PAI-1 by S1P has not yet been thoroughly elucidated. The present study was undertaken to determine whether S1P has important effects on the posttranscriptional regulation of PAI-1 expression. To evaluate this possibility, we determined promoter activity, mRNA levels, 3'-untranslated region (UTR) activity, and protein levels of PAI-1 in HepG2 cells. S1P increased PAI-1 promoter activity and the expression of PAI-1 mRNA within 4h of exposure. It decreased the expression of PAI-1 mRNA and the accumulation of PAI-1 protein into the media in 24h. Human PAI-1 mRNA exists in two subspecies (3.2 and 2.2kb). S1P decreased the baseline luciferase activity of the 1kb fragment of the 3' terminus (+2177 to 3176nt) of the 3'-UTR of the 3.2kb PAI-1 mRNA [3'-UTR (+2177-3176)]. S1P decreased expression of PAI-1 protein, presumably by regulating PAI-1 expression at the posttranscriptional level thereby affecting mRNA stability. SERPINE1 mRNA binding protein (SERBP1) and ARE3 in the 3'-UTR were involved in the posttranscriptional regulation by S1P. Our data suggest that S1P can destabilize 3.2kb PAI-1 mRNA through specific effects on the 3'-UTR. These effects appear to involve SERBP1 leading to decreased expression of PAI-1 protein.
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http://dx.doi.org/10.1016/j.bbagrm.2012.07.001 | DOI Listing |
Sci Rep
December 2024
Clinical Laboratory, Hebei General Hospital, Shijiazhuang, Hebei, China.
Objective: To explore the influence of SALL4 in cardiac fibroblasts on the progression of myocardial infarction.
Methods: Analysis of genes specifically expressed in myocardial infarction by bioinformatics methods; The impact of SALL4 on myocardial infarction was assessed using mouse ultrasound experiments and Masson staining; The effect of SALL4 on the expression levels of collagen-I and collagen-III in myocardial tissue was examined by immunohistochemical staining; The migration ability of cardiac fibroblasts was evaluated using a Transwell assay; The proliferative ability of cardiac fibroblasts was tested using a CCK-8 assay; The relative fluorescence intensity of α-SMA and CTGF in cardiac fibroblasts were checked through immunofluorescence staining experiment; The expression of SALL4, DOT1L, H3K79me2, P53, SHP2, YAP, nucleus-YAP, collagen-I, α-SMA, CTGF, and PAI-1 in myocardial tissues or cardiac fibroblasts was detected using western blot analysis.
Results: SALL4-specific high expression in myocardial infarction; SALL4 intensified the alterations in the heart structure of mice with myocardial infarction and worsened the fibrosis of myocardial infarction; SALL4 also promoted the expression of SALL4, DOT1L, H3K79me2, P53, SHP2, YAP, nucleus-YAP, collagen-I, collagen-III, α-SMA, CTGF, and PAI-1 in myocardial infarction tissues and cardiac fibroblasts; Subsequently, SALL4 could enhance the immunofluorescence intensity of α-SMA and CTGF; Moreover, SALL4 could promote the proliferation and migration of cardiac fibroblasts.
Cancer Genomics Proteomics
December 2024
University Medical Center Göttingen, Department of Gynecology and Obstetrics, Göttingen, Germany
Background/aim: G protein-coupled estrogen receptor 1 (GPER1) appears to play a tumor-suppressive role in cervical squamous cell carcinoma (CSCC)GPER1 suppression leads to significantly increased expression of serpin family E member 1 (SERPINE1)/protein plasminogen activator inhibitor type 1 (PAI-1). The question arises, what role does SERPINE1/PAI-1 play in GPER1-dependent tumorigenic potential of CSCC.
Materials And Methods: SiHa and C33A CSCC cells were treated with GPER1 agonist G1 or antagonist G36.
Decidualization of endometrial stromal cells is a prerequisite for successful embryo implantation and early pregnancy. Decidualization dysregulation results in implantation failure. In our previous study, we reported that PAI-1 is abnormally downregulated in the endometrial tissue samples of patients with recurrent implantation failure.
View Article and Find Full Text PDFJ Transl Med
December 2024
Chongqing Key Laboratory of Traditional Chinese Medicine for Prevention and Cure of Metabolic Diseases, College of Traditional Chinese Medicine, Chongqing Medical University, Chongqing, 400016, China.
Background: Scutellaria baicalensis Georgi, a traditional Chinese herb, is known for its various biological effects, including antibacterial, anti-inflammatory, antioxidative, and antitumor properties. However, the function and mechanisms of methanol extract of Scutellaria baicalensis Georgi (MESB) in treating hepatic fibrosis remain unclear.
Methods: This study utilized a CCl4-induced mouse model of hepatic fibrosis to assess the effects of MESB through histopathological analysis and serum tests.
Cell Death Dis
December 2024
Key Laboratory of Experimental Teratology, Ministry of Education, Department of Histology and Embryology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.
Acute kidney injury (AKI) caused by nephrotoxins, ischemia reperfusion (IR) or sepsis is associated with high morbidity and mortality. Unveiling new mechanisms underlying AKI can help develop new therapeutic strategy. Cullin 4B (CUL4B) is a scaffold protein in the CUL4B-RING E3 ubiquitin ligase (CRL4B) complex.
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