Plasminogen activator inhibitor type-1 (PAI-1) is the major physiologic regulator of the plasmin-based pericellular proteolytic cascade and a critical element in pathologic angiogenesis in vivo. PAI-1 controls stromal proteolysis (i.e., maintains an angiogenic """"""""scaffold"""""""") and stabilizes nascent capillary vessel structure. Our findings as well as others indicate that PAI-1 negatively modulates a plasmin/matrix metalloproteinase (MMP) cascade that regulates collagen degradation, capillary regression and endothelial apoptosis. Our continued definition of mechanistic controls on endothelial PAI-1 gene expression may lead to new therapies for the treatment of diseases in which exuberant or non-resolving angiogenesis is a major pathogenic feature (e.g., arthritis, psoriasis, cancer, cardiovascular and pulmonary fibrosis, diabetic retinopathy, macular degeneration, excessive scaring disorders). In the previous funding period, we established that TGF-p1- stimulated PAI-1 expression requires cooperative EGFR/pp60G""""""""s/c and MEK signaling and involved the rho kinase pp160ROCK. PAI-1 transcription in response to TGF-p1, moreover, required binding of upstream stimulatory factor (USF) to a critical E box motif (CACGTG) in the PAI-1 promoter. Chromatin immunopre- cipitation confirmed that PAI-1 is a direct USF target gene and that TGF-pl-induced PAI-1 expression involves a subtype switch (USF1->USF2) at the E box site. USF, furthermore, formed transient complexes with pERK and interference with EGFR, ppSO0""""""""5""""""""1 or p160ROCK activity or ERK/p38 signaling ablated induced PAI-1 expression. Importantly, targeted PAI-1 down-regulation with siRNA or antisense constructs or expression of dominant-negative USF mutants as well as use of PAI-1 neutralizing reagents accelerated plasminogen-induced collagen degradation and vessel regression. Our hypothesis is that TGF-B1 stimulates PAI-1 transcription through cooperative pathways that modulate the activation state of the EGFR and regulate MAP kinase/USF interactions. The following aims will address this hypothesis: (1) to characterize MAP kinase/USF interactions and phosphorylation site requirements in endothelial cells that regulate USF/DNA binding and PAI-1 transcription, (2) to determine the mechanism by which TGF-R.1 activates the EGFR and r/?o/p160ROCK signaling. Our continued clarification of mechanistic controls on PAI-1 gene expression may lead to new targeted therapies for diseases in which excessive or non-resolving angiogenesis is a major pathogenic feature.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM057242-12
Application #
7849725
Study Section
Surgery, Anesthesiology and Trauma Study Section (SAT)
Program Officer
Hagan, Ann A
Project Start
1998-05-01
Project End
2013-05-31
Budget Start
2010-06-01
Budget End
2013-05-31
Support Year
12
Fiscal Year
2010
Total Cost
$310,860
Indirect Cost
Name
Albany Medical College
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
190592162
City
Albany
State
NY
Country
United States
Zip Code
12208
Samarakoon, Rohan; Rehfuss, Alexandra; Khakoo, Nidah S et al. (2016) Loss of expression of protein phosphatase magnesium-dependent 1A during kidney injury promotes fibrotic maladaptive repair. FASEB J 30:3308-3320
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Simone, Tessa M; Higgins, Stephen P; Archambeault, Jaclyn et al. (2015) A small molecule PAI-1 functional inhibitor attenuates neointimal hyperplasia and vascular smooth muscle cell survival by promoting PAI-1 cleavage. Cell Signal 27:923-33
Higgins, Paul J; Shahzad, Aamir; Kennedy, Jeffrey (2015) Accredited translational medicine centre: Human renal fibrotic disease: Translational research at the Center for Cell Biology and Cancer Research (CCBCR), Albany Medical College, Albany, NY. New Horiz Transl Med 2:51-54
Simone, Tessa M; Higgins, Stephen P; Higgins, Craig E et al. (2014) Chemical Antagonists of Plasminogen Activator Inhibitor-1: Mechanisms of Action and Therapeutic Potential in Vascular Disease. J Mol Genet Med 8:
Simone, Tessa M; Higgins, Paul J (2014) Small Molecule PAI-1 Functional Inhibitor Attenuates Vascular Smooth Muscle Cell Migration and Survival: Implications for the Therapy of Vascular Disease. New Horiz Transl Med 2:16-19
Qi, Li; Higgins, Craig E; Higgins, Stephen P et al. (2014) The basic helix-loop-helix/leucine zipper transcription factor USF2 integrates serum-induced PAI-1 expression and keratinocyte growth. J Cell Biochem 115:1840-7
Overstreet, Jessica M; Samarakoon, Rohan; Meldrum, Kirstan K et al. (2014) Redox control of p53 in the transcriptional regulation of TGF-?1 target genes through SMAD cooperativity. Cell Signal 26:1427-36
Higgins, Paul J (2014) Balancing AhR-Dependent Pro-Oxidant and Nrf2-Responsive Anti-Oxidant Pathways in Age-Related Retinopathy: Is SERPINE1 Expression a Therapeutic Target in Disease Onset and Progression? J Mol Genet Med 8:101

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