Plasminogen activator inhibitor-1 (PAI-1) plays an important role in the pathogenesis of obesity-driven type 2 diabetes mellitus and associated cardiovascular complications. Here, we show that perturbation of caveolar microdomains leads to insulin resistance and concomitant up-regulation of PAI-1 in 3T3L1 adipocytes. We present several lines of evidence showing that the phosphatidylinositol 3-kinase (PI3K) pathway negatively regulates PAI-1 gene expression. Insulin-induced PAI-1 gene expression is up-regulated by a specific inhibitor of PI3K. In addition, serum PAI-1 level is elevated in protein kinase Balpha-deficient mice, whereas it is reduced in p70 ribosomal S6 kinase 1-deficient mice. The PI3K pathway phosphorylates retinoblastoma protein (pRB), known to release free E2 (adenoviral protein) factor (E2F), which we have previously demonstrated to be a transcriptional repressor of PAI-1 gene expression. Accordingly, cell-penetrating peptides that disrupt pRB-E2F interaction, and thereby release free E2F, are able to suppress PAI-1 levels that are elevated during insulin-resistant conditions. This study identifies a caveolar-dependent signal pathway that up-regulates PAI-1 in insulin-resistant adipocytes and proposes a previously undescribed pharmacological paradigm of disrupting pRB-E2F interaction to suppress PAI-1 levels.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC535371PMC
http://dx.doi.org/10.1073/pnas.0405278101DOI Listing

Publication Analysis

Top Keywords

pai-1 gene
12
gene expression
12
pai-1
9
signal pathway
8
plasminogen activator
8
activator inhibitor-1
8
insulin-resistant adipocytes
8
pi3k pathway
8
release free
8
prb-e2f interaction
8

Similar Publications

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.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

LINC02257 regulates malignant phenotypes of colorectal cancer via interacting with miR-1273g-3p and YB1.

Cell Death Dis

December 2024

Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul, 06351, Republic of Korea.

Colorectal cancer (CRC) is the third most common cancer diagnosed and the second leading cause of cancer-related deaths. Emerging evidence has indicated that long non-coding RNAs (lncRNAs) are involved in the progression of various types of cancer. In this study, we aimed to identify potential causal lncRNAs in CRC through comprehensive multilevel bioinformatics analyses, coupled with functional validation.

View Article and Find Full Text PDF

Bruton tyrosine kinase promotes wound healing after myocardial infarction by inhibiting the transcription of u-PA.

Free Radic Biol Med

December 2024

Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China; Key Laboratory of Viral Heart Diseases, National Health Commission, Shanghai, China; Key Laboratory of Viral Heart Diseases, Chinese Academy of Medical Sciences, Shanghai, China; National Clinical Research Center for Interventional Medicine, Shanghai, China.

Backgrounds: Bruton tyrosine kinase (BTK), which is highly expressed in immune cells, plays a critical role in regulating the function of macrophages. A growing body of evidence has demonstrated that the accumulation of macrophages in cardiac tissue after myocardial infarction (MI) significantly affects wound healing and ventricular remodeling during the early phase of repair after MI. However, the role of BTK in cardiac repair post-MI, especially in macrophage-mediated repair, remains unclear.

View Article and Find Full Text PDF

: This study aims to investigate the role of congenital single nucleotide thrombophilia in young females with early recurrent pregnancy loss (RPL). : We studied 120 pregnant females with RPL and 80 matched females as a control with no RPL. Females were aged ≤ 35 years, had at least two consecutive first-trimester RPLs, and the acquired cause of RPL was excluded.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!