scholarly journals TAZ activation drives fibroblast spheroid growth, expression of profibrotic paracrine signals, and context-dependent ECM gene expression

2017 ◽  
Vol 312 (3) ◽  
pp. C277-C285 ◽  
Author(s):  
Amy J. Jorgenson ◽  
Kyoung Moo Choi ◽  
Delphine Sicard ◽  
Karry M. J. Smith ◽  
Samantha E. Hiemer ◽  
...  
Keyword(s):  
Gene Expression ◽  
Hippo Pathway ◽  
Plasminogen Activator Inhibitor ◽  
Tissue Growth ◽  
Hanging Drop ◽  
Plasminogen Activator Inhibitor 1 ◽  
Spheroid Culture ◽  
Fibroblast Activation ◽  
Context Dependent ◽  
Hanging Drop Culture

Recent studies have implicated the Hippo pathway and its transcriptional effectors YAP and TAZ as necessary for fibroblast activation and tissue fibrosis. To test the specific and sufficient roles for TAZ in driving autonomous fibroblast activation, we cultured NIH3T3 fibroblasts expressing a doxycycline-inducible nuclear-localized mutant of TAZ (TAZ4SA) in scaffold-free 3D hanging drop spheroids, or on matrices of specified mechanical rigidity. Control NIH3T3 fibroblasts formed spheroids in hanging drop culture that remained stable and neither increased nor decreased in size significantly over 15 days. In contrast, TAZ4SA-transduced fibroblasts grew robustly in spheroid culture, and expressed enhanced levels of genes encoding profibrotic soluble factors connective tissue growth factor (CTGF), endothelin-1 (Et-1), and plasminogen activator inhibitor 1 (PAI-1). However, TAZ4SA expression was unable to enhance expression of extracellular matrix (ECM)-encoding genes Col1a1, Col1a2, Col3a1, or Fn1 in spheroid culture. Micromechanical testing indicated that spheroids composed of either control or TAZ4SA-expressing cells were highly compliant and indistinguishable in mechanical properties. In fibroblasts cultured on 2D matrices of compliance similar to spheroids, TAZ4SA expression was able to enhance contractile force generation, but was unable to enhance ECM gene expression. In contrast, culture on stiff hydrogels potentiated TAZ4SA enhancement of ECM expression. TAZ4SA enhancement of Col1a1 expression on soft matrices was potentiated by TGF-β1, while on stiff matrices it was abrogated by inhibition of myocardin-related transcription factor, demonstrating context-dependent crosstalk of TAZ with these pathways. These findings demonstrate sufficiency of TAZ activation for driving fibroblast proliferation, contraction, and soluble profibrotic factor expression, and mechanical context-dependent crosstalk of TAZ with other pathways in regulating Col1a1 expression.

Bezafibrate Induces Plasminogen Activator Inhibitor-1 Gene Expression in a CLOCK-Dependent Circadian Manner

2010 ◽  
Vol 78 (1) ◽  
pp. 135-141 ◽  
Author(s):  
Katsutaka Oishi ◽  
Satoru Koyanagi ◽  
Naoya Matsunaga ◽  
Koji Kadota ◽  
Eriko Ikeda ◽  
...  
Keyword(s):  
Gene Expression ◽  
Plasminogen Activator ◽  
Plasminogen Activator Inhibitor ◽  
Plasminogen Activator Inhibitor 1 ◽  
Activator Inhibitor

Early genetic responses in rat vascular tissue after simulated diving

2012 ◽  
Vol 44 (24) ◽  
pp. 1201-1207 ◽  
Author(s):  
Ingrid Eftedal ◽  
Arve Jørgensen ◽  
Ragnhild Røsbjørgen ◽  
Arnar Flatberg ◽  
Alf O. Brubakk
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Plasminogen Activator ◽  
Differential Gene Expression ◽  
Vascular Function ◽  
Plasminogen Activator Inhibitor ◽  
Fine Tuning ◽  
Plasminogen Activator Inhibitor 1 ◽  
Differential Gene ◽  
Activator Inhibitor

Diving causes a transient reduction of vascular function, but the mechanisms behind this are largely unknown. The aim of this study was therefore to analyze genetic reactions that may be involved in acute changes of vascular function in divers. Rats were exposed to 709 kPa of hyperbaric air (149 kPa Po2) for 50 min followed by postdive monitoring of vascular bubble formation and full genome microarray analysis of the aorta from diving rats ( n = 8) and unexposed controls ( n = 9). Upregulation of 23 genes was observed 1 h after simulated diving. The differential gene expression was characteristic of cellular responses to oxidative stress, with functions of upregulated genes including activation and fine-tuning of stress-responsive transcription, cytokine/cytokine receptor signaling, molecular chaperoning, and coagulation. By qRT-PCR, we verified increased transcription of neuron-derived orphan receptor-1 ( Nr4a3), plasminogen activator inhibitor 1 ( Serpine1), cytokine TWEAK receptor FN14 ( Tnfrsf12a), transcription factor class E basic helix-loop-helix protein 40 ( Bhlhe40), and adrenomedullin ( Adm). Hypoxia-inducible transcription factor HIF1 subunit HIF1-α was stabilized in the aorta 1 h after diving, and after 4 h there was a fivefold increase in total protein levels of the procoagulant plasminogen activator inhibitor 1 (PAI1) in blood plasma from diving rats. The study did not have sufficient power for individual assessment of effects of hyperoxia and decompression-induced bubbles on postdive gene expression. However, differential gene expression in rats without venous bubbles was similar to that of all the diving rats, indicating that elevated Po2 instigated the observed genetic reactions.

Regional Variation in Plasminogen Activator Inhibitor-1 Expression in Adipose Tissue from Obese Individuals

2000 ◽  
Vol 83 (04) ◽  
pp. 545-548 ◽  
Author(s):  
Vanessa Van Harmelen ◽  
Johan Hoffstedt ◽  
Per Lundquist ◽  
Hubert Vidal ◽  
Veronika Stemme ◽  
...  
Keyword(s):  
Gene Expression ◽  
Adipose Tissue ◽  
Visceral Adipose Tissue ◽  
Subcutaneous Adipose Tissue ◽  
Plasminogen Activator Inhibitor ◽  
Plasminogen Activator Inhibitor 1 ◽  
Visceral Adipose ◽  
Subcutaneous Adipose ◽  
Activator Inhibitor ◽  
Pai 1

SummaryHigh plasma plasminogen activator inhibitor-1 (PAI-1) activity is a frequent finding in obesity and adipose tissue has recently been suggested to be a source of circulating PAI-1 in humans. In the present study, differences in adipose tissue gene expression and protein secretion rate of PAI-1 between subcutaneous and visceral adipose tissue was analysed in specimens obtained from 22 obese individuals. The secretion rate of PAI-1 was two-fold higher in subcutaneous adipose tissue than in visceral adipose tissue (292 ± 50 vs 138 ± 24 ng PAI-1/107 cells, P <0.05). In accordance with the secretion data, subcutaneous adipose tissue contained about three-fold higher levels of PAI-1 mRNA than visceral adipose tissue (2.43 ± 0.37 vs 0.81 ± 0.12 attomole PAI-1 mRNA/µg total RNA, P <0.001). PAI-1 secretion from subcutaneous but not from visceral adipose tissue correlated significantly with cell size (r = 0.43, P <0.05). In summary, subcutaneous adipose tissue secreted greater amounts of PAI-1 and had a higher PAI-1 gene expression than visceral adipose tissue from the same obese individuals. Bearing in mind that subcutaneous adipose tissue is the largest fat depot these finding may be important for the coagulation abnormalities associated with obesity.

Role of connective tissue growth factor in the pathogenesis of diabetic nephropathy

2001 ◽  
Vol 359 (1) ◽  
pp. 77-87 ◽  
Author(s):  
Nadia Abdel WAHAB ◽  
Natalia YEVDOKIMOVA ◽  
Benjamin S. WESTON ◽  
Terry ROBERTS ◽  
Xin Jun LI ◽  
...  
Keyword(s):  
Diabetic Nephropathy ◽  
Growth Factor ◽  
Connective Tissue ◽  
High Glucose ◽  
Mesangial Cell ◽  
Plasminogen Activator Inhibitor ◽  
Tissue Growth ◽  
Mrna Levels ◽  
Plasminogen Activator Inhibitor 1 ◽  
Activator Inhibitor

We characterized a rabbit polyclonal antibody raised against human recombinant connective tissue growth factor (CTGF). The antibody recognised a higher molecular mass form (approx. 56kDa) of CTGF in mesangial cell lysates as well as the monomeric (36–38kDa) and lower molecular mass forms (< 30kDa) reported previously. Immunohistochemistry detected CTGF protein in glomeruli of kidneys of non-obese diabetic mice 14 days after the onset of diabetes, and this was prominent by 70 days. CTGF protein is also present in glomeruli of human patients with diabetic nephropathy. No CTGF was detected in either normal murine or human glomeruli. Transient transfection of a transformed human mesangial cell line with a CTGF–V5 epitope fusion protein markedly increased fibronectin and plasminogen activator inhibitor-1 synthesis in cultures maintained in normal glucose (4mM) conditions; a CTGF-antisense construct reduced the elevated synthesis of these proteins in high glucose (30mM) cultures. Culture of primary human mesangial cells for 14 days in high glucose, or in low glucose supplemented with recombinant CTGF or transforming growth factor β1, markedly increased CTGF mRNA levels and fibronectin synthesis. However, whilst co-culture with a CTGF-antisense oligonucleotide reduced the CTGF mRNA pool by greater than 90% in high glucose, it only partially reduced fibronectin mRNA levels and synthesis. A chick anti-CTGF neutralizing antibody had a similar effect on fibronectin synthesis. Thus both CTGF and CTGF-independent pathways mediate increased fibronectin synthesis in high glucose. Nevertheless CTGF expression in diabetic kidneys is likely to be a key event in the development of glomerulosclerosis by affecting both matrix synthesis and, potentially through plasminogen activator inhibitor-1, its turnover.

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