scholarly journals Thyroid Hormone Increases TGF-β1 in Cardiomyocytes Cultures Independently of Angiotensin II Type 1 and Type 2 Receptors

2010 ◽  
Vol 2010 ◽  
pp. 1-7 ◽  
Author(s):  
Gabriela Placoná Diniz ◽  
Marcela Sorelli Carneiro-Ramos ◽  
Maria Luiza Morais Barreto-Chaves

TH-induced cardiac hypertrophyin vivois accompanied by increased cardiac Transforming Growth Factor-β1 (TGF-β1) levels, which is mediated by Angiotensin II type 1 receptors (AT1R) and type 2 receptors (AT2R). However, the possible involvement of this factor in TH-induced cardiac hypertrophy is unknown. In this study we evaluated whether TH is able to modulate TGF-β1 in isolated cardiac, as well as the possible contribution of AT1R and AT2R in this response. The cardiac fibroblasts treated withT3did not show alteration on TGF-β1 expression. However, cardiomyocytes treated withT3presented an increase in TGF-β1 expression, as well as an increase in protein synthesis. The AT1R blockade prevented theT3-induced cardiomyocyte hypertrophy, while the AT2R blockage attenuated this response. TheT3-induced increase on TGF-β1 expression in cardiomyocytes was not changed by the use of AT1R and AT2R blockers. These results indicate that Angiotensin II receptors are not implicated inT3-induced increase on TGF-βexpression and suggest that the trophic effects exerted byT3on cardiomyocytes are not dependent on the higher TGF-β1 levels, since the AT1R and AT2R blockers were able to attenuate theT3-induced cardiomyocyte hypertrophy but were not able to attenuate the increase on TGF-β1 levels promoted byT3.

2001 ◽  
Vol 281 (5) ◽  
pp. C1457-C1467 ◽  
Author(s):  
Gaétan Thibault ◽  
Marie-Josée Lacombe ◽  
Lynn M. Schnapp ◽  
Alexandre Lacasse ◽  
Fatiha Bouzeghrane ◽  
...  

Using a novel pharmacological tool with125I-echistatin to detect integrins on the cell, we have observed that cardiac fibroblasts harbor five different RGD-binding integrins: α8β1, α3β1, α5β1, αvβ1, and αvβ3. Stimulation of cardiac fibroblasts by angiotensin II (ANG II) or transforming growth factor-β1 (TGF-β1) resulted in an increase of protein and heightening by 50% of the receptor density of α8β1-integrin. The effect of ANG II was blocked by an AT1, but not an AT2, receptor antagonist, or by an anti-TGF-β1 antibody. ANG II and TGF-β1 increased fibronectin secretion, smooth muscle α-actin synthesis, and formation of actin stress fibers and enhanced attachment of fibroblasts to a fibronectin matrix. The α8- and β1-subunits were colocalized by immunocytochemistry with vinculin or β3-integrin at focal adhesion sites. These results indicate that α8β1-integrin is an abundant integrin on rat cardiac fibroblasts. Its positive modulation by ANG II and TGF-β1 in a myofibroblast-like phenotype suggests the involvement of α8β1-integrin in extracellular matrix protein deposition and cardiac fibroblast adhesion.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1601-1601
Author(s):  
Sugata Hazra ◽  
Yagna P.R. Jarajapu ◽  
Li Liu ◽  
Sergio Caballero ◽  
Valerie Stepps ◽  
...  

Abstract Abstract 1601 Objective: The dysfunction of human diabetic CD34+ endothelial progenitor cells limits their utility in autologous cell therapy for vascular complications. Previously, we showed that transient inhibition of transforming growth factor-beta 1 (TGF-β1) enhances vascular reparative function of human CD34+ cells isolated from diabetics (Bhatwadekar et al, 2010). Expression of PAI-1, the major gene product of TGF-β1 activation, is increased by high glucose and insulin exposure in endothelial cells and PAI-1 has been shown to be increased in the serum of diabetics. We asked whether the beneficial effects of TGF-β1 blockade on CD34+ cells function were mediated by inhibition of PAI-1 and whether blocking of PAI-1 could correct diabetes associated dysfunction of these cells. Research Design and Methods: Plasma determinations of PAI-1 and TGF-β1 (both measured by ELISA) were compared in type 2 (n=17) and type 1 (n=7) diabetic patients. CD34+ cells from these individuals were isolated and analyzed for cell survival (in the presence and absence of growth factors), cell proliferation, cell cycle analysis and migration. The effect of TGF-β1 phosphorodiamidate morpholino oligomers (PMO) treatment on PAI-1 level was determined in CD34+ cells. In CD34+ cells, PAI-1 was blocked using either lentivirus expressing PAI-1 shRNA or PAI-1 siRNA. In vivo homing ability of PAI-1 inhibited CD34+ cells was assessed using an ocular model of ischemia/reperfusion (I/R) Injury. Results: Plasma PAI-1 level was increased in type 2 diabetic patients compared to type 1 (p<0.05) and directly correlated with TGF-β1 plasma levels (r= 0.44). TGF-β1 PMO treatment resulted in a reduction of PAI-1 mRNA expression (p=0.0018 in diabetic, p=0.05 in non-diabetic). PAI-1 blockade promoted EPC proliferation in vitro and bypassed the inhibitory effect of TGF-β1 on cell survival (p<0.001) even in the absence of growth factors. PAI-1 blockade enhanced the migration of these cells in response to SDF-1α in (p<0.01) compared to cells treated with scrambled siRNA and improved the in vivo re-endothelialization by CD34+ cells in the I/R model. Conclusions: Our results suggest that the cytostatic activity of TGF-β1 in CD34+ cells is mediated largely through PAI-1. Blocking PAI-1 corrects multiple defects in CD34+ cells from type 2 diabetic patients. This approach may offer a promising therapeutic strategy for restoring vascular reparative function in diabetic cells and facilitate their use in autologous cell therapy. Disclosures: No relevant conflicts of interest to declare.


1993 ◽  
Vol 20 (9) ◽  
pp. 555-562 ◽  
Author(s):  
Julie Blasioli ◽  
Athena Kladis ◽  
Iain J. Clarke ◽  
Duncan J. Campbell

2018 ◽  
Vol 96 (5) ◽  
pp. 527-534 ◽  
Author(s):  
Brice Ongali ◽  
Nektaria Nicolakakis ◽  
Xin-Kang Tong ◽  
Clotilde Lecrux ◽  
Hans Imboden ◽  
...  

Transgenic mice constitutively overexpressing the cytokine transforming growth factor-β1 (TGF-β1) (TGF mice) display cerebrovascular alterations as seen in Alzheimer’s disease (AD) and vascular cognitive impairment and dementia (VCID), but no or only subtle cognitive deficits. TGF-β1 may exert part of its deleterious effects through interactions with angiotensin II (AngII) type 1 receptor (AT1R) signaling pathways. We test such interactions in the brain and cerebral vessels of TGF mice by measuring cerebrovascular reactivity, levels of protein markers of vascular fibrosis, nitric oxide synthase activity, astrogliosis, and mnemonic performance in mice treated (6 months) with the AT1R blocker losartan (10 mg/kg per day) or the angiotensin converting enzyme inhibitor enalapril (3 mg/kg per day). Both treatments restored the severely impaired cerebrovascular reactivity to acetylcholine, calcitonin gene-related peptide, endothelin-1, and the baseline availability of nitric oxide in aged TGF mice. Losartan, but not enalapril, significantly reduced astrogliosis and cerebrovascular levels of profibrotic protein connective tissue growth factor while raising levels of antifibrotic enzyme matrix metallopeptidase-9. Memory was unaffected by aging and treatments. The results suggest a pivotal role for AngII in TGF-β1-induced cerebrovascular dysfunction and neuroinflammation through AT1R-mediated mechanisms. Further, they suggest that AngII blockers could be appropriate against vasculopathies and astrogliosis associated with AD and VCID.


2002 ◽  
Vol 283 (1) ◽  
pp. F173-F180 ◽  
Author(s):  
Guohua Ding ◽  
Krishna Reddy ◽  
Aditi A. Kapasi ◽  
Nicholas Franki ◽  
Nora Gibbons ◽  
...  

ANG II has been shown to modulate kidney cell growth and contribute to the pathobiology of glomerulosclerosis. Glomerular visceral epithelial cell (GEC) injury or loss is considered to play a pivotal role in the initiation and progression of glomerulosclerosis. In the present study, we investigated the effect of ANG II on GEC apoptosis. Rat GECs were incubated with increasing doses of ANG II for variable time periods. Apoptosis was evaluated by cell nucleus staining and DNA fragmentation assay. ANG II induced GEC apoptosis in a dose- and time-dependent manner. The proapoptotic effect was attenuated by the ANG II receptor type 1 antagonist losartan or the ANG II receptor type 2 antagonist PD-123319 and was completely blocked by incubation with the combined antagonists. Moreover, ANG II stimulated transforming growth factor (TGF)-β1 production as measured by ELISA. GECs exposed to TGF-β1 demonstrated a dose- and time-dependent increase in apoptosis. ANG II-induced apoptosis was significantly inhibited by addition of anti-TGF-β1 antibody. ANG II also upregulated the expression of Fas, FasL, and Bax and downregulated the expression of Bcl-2 in GECs. These studies suggest that ANG II induces GEC apoptosis by a mechanism involving TGF-β1 expression that may, importantly, contribute to the pathogenesis of glomerulosclerosis.


2017 ◽  
Vol 41 (5) ◽  
pp. 2004-2015 ◽  
Author(s):  
Zeng-xiang Dong ◽  
Lin Wan ◽  
Ren-jun Wang ◽  
Yuan-qi Shi ◽  
Guang-zhong Liu ◽  
...  

Background/Aims: Flavonol (–)-epicatechin (EPI) is present in high amounts in cocoa and tea products, and has been shown to exert beneficial effects on the cardiovascular system. However, the precise mechanism of EPI on cardiomyocyte hypertrophy has not yet been determined. In this study, we examined whether EPI could inhibit cardiac hypertrophy. Methods: We utilised cultured neonatal mouse cardiomyocytes and mice for immunofluorescence, immunochemistry, qRT-PCR, and western blot analyses. Results: 1µM EPI significantly inhibited 1µM angiotensin II (Ang II)-induced increase of cardiomyocyte size, as well as the mRNA and protein levels of ANP, BNP and β-MHC in vitro. The effects of EPI were accompanied with an up-regulation of SP1 and SIRT1, and were abolished by SP1 inhibition. Up-regulation of SP1 could block Ang II-induced increase in cardiomyocyte size, as well as the mRNA and protein levels of ANP, BNP and β-MHC, and increase the protein levels of SIRT1 in vitro. Moreover, 1 mg/kg body weight/day EPI significantly inhibited mouse cardiac hypertrophy induced by Ang II, which could be eliminated by SP1 inhibition in vivo. Conclusion: Our data indicated that EPI inhibited AngII-induced cardiac hypertrophy by activating the SP1/SIRT1 signaling pathway.


2001 ◽  
Vol 194 (6) ◽  
pp. 809-822 ◽  
Author(s):  
Chun Geun Lee ◽  
Robert J. Homer ◽  
Zhou Zhu ◽  
Sophie Lanone ◽  
Xiaoman Wang ◽  
...  

Interleukin (IL)-13 is a key mediator of tissue fibrosis caused by T helper cell type 2 inflammation. We hypothesized that the fibrogenic effects of IL-13 are mediated by transforming growth factor (TGF)-β. To test this hypothesis we compared the regulation of TGF-β in lungs from wild-type mice and CC10-IL-13 mice in which IL-13 overexpression causes pulmonary fibrosis. IL-13 selectively stimulated TGF-β1 production in transgenic animals and macrophages were the major site of TGF-β1 production and deposition in these tissues. IL-13 also activated TGF-β1 in vivo. This activation was associated with decreased levels of mRNA encoding latent TGF-β–binding protein-1 and increased mRNA encoding urinary plasminogen activator, matrix metalloproteinase (MMP)-9, and CD44. TGF-β1 activation was abrogated by the plasmin/serine protease antagonist aprotinin. It was also decreased in progeny of crosses of CC10-IL-13 mice and MMP-9 null mice but was not altered in crosses with CD44 null animals. IL-13–induced fibrosis was also significantly ameliorated by treatment with the TGF-β antagonist soluble TGFβR-Fc (sTGFβR-Fc). These studies demonstrate that IL-13 is a potent stimulator and activator of TGF-β1 in vivo. They also demonstrate that this activation is mediated by a plasmin/serine protease- and MMP-9–dependent and CD44-independent mechanism(s) and that the fibrogenic effects of IL-13 are mediated, in great extent, by this TGF-β pathway.


2021 ◽  
Vol 22 (18) ◽  
pp. 9944
Author(s):  
Yongwoon Lim ◽  
Anna Jeong ◽  
Duk-Hwa Kwon ◽  
Yeong-Un Lee ◽  
Young-Kook Kim ◽  
...  

Various heart diseases cause cardiac remodeling, which in turn leads to ineffective contraction. Although it is an adaptive response to injury, cardiac fibrosis contributes to this remodeling, for which the reactivation of quiescent myofibroblasts is a key feature. In the present study, we investigated the role of the p300/CBP-associated factor (PCAF), a histone acetyltransferase, in the activation of cardiac fibroblasts. An intraperitoneal (i.p.) injection of a high dose (160 mg/kg) of isoproterenol (ISP) induced cardiac fibrosis and reduced the amount of the PCAF in cardiac fibroblasts in the mouse heart. However, the PCAF activity was significantly increased in cardiac fibroblasts, but not in cardiomyocytes, obtained from ISP-administered mice. An in vitro study using human cardiac fibroblast cells recapitulated the in vivo results; an treatment with transforming growth factor-β1 (TGF-β1) reduced the PCAF, whereas it activated the PCAF in the fibroblasts. PCAF siRNA attenuated the TGF-β1-induced increase in and translocation of fibrosis marker proteins. PCAF siRNA blocked TGF-β1-mediated gel contraction and cell migration. The PCAF directly interacted with and acetylated mothers against decapentaplegic homolog 2 (SMAD2). PCAF siRNA prevented TGF-β1-induced phosphorylation and the nuclear localization of SMAD2. These results suggest that the increase in PCAF activity during cardiac fibrosis may participate in SMAD2 acetylation and thereby in its activation.


2019 ◽  
Vol 116 (1) ◽  
pp. 114-126 ◽  
Author(s):  
Xiaoying Yan ◽  
Ran Zhao ◽  
Xiaorong Feng ◽  
Jingzhou Mu ◽  
Ying Li ◽  
...  

Abstract Aims Sialylation is up-regulated during the development of cardiac hypertrophy. Sialyltransferase7A (Siat7A) mRNA is consistently over-expressed in the hypertrophic left ventricle of hypertensive rats independently of genetic background. The aims of this study were: (i) to detect the Siat7A protein levels and its roles in the pathological cardiomyocyte hypertrophy; (ii) to elucidate the effect of sialylation mediated by Siat7A on the transforming-growth-factor-β-activated kinase (TAK1) expression and activity in cardiomyocyte hypertrophy; and (iii) to clarify hypoxia-inducible factor 1 (HIF-1) expression was regulated by Siat7A and transactivated TAK1 expression in cardiomyocyte hypertrophy. Methods and results Siat7A protein level was increased in hypertrophic cardiomyocytes of human and rats subjected to chronic infusion of angiotensin II (ANG II). Delivery of adeno-associated viral (AAV9) bearing shRNA against rat Siat7A into the left ventricular wall inhibited ventricular hypertrophy. Cardiac-specific Siat7A overexpression via intravenous injection of an AAV9 vector encoding Siat7A under the cardiac troponin T (cTNT) promoter aggravated cardiac hypertrophy in ANG II-treated rats. In vitro, Siat7A knockdown inhibited the induction of Sialyl-Tn (sTn) antigen and cardiomyocyte hypertrophy stimulated by ANG II. Mechanistically, ANG II induced the activation of TAK1-nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signalling in parallel to up-regulation of Siat7A in hypertrophic cardiomyocytes. Siat7A knockdown inhibited activation of TAK1-NF-κB pathway. Interestingly, HIF-1α expression was increased in cardiomyocytes stimulated by ANG II but decreased after Siat7A knockdown. HIF-1α knockdown efficiently decreased TAK1 expression. ChIP and luciferase assays showed that HIF-1α transactivated the TAK1 promoter region (nt −1285 to −1274 bp) in the cardiomyocytes following ANG II stimulus. Conclusion Siat7A was up-regulated in hypertrophic myocardium and promoted cardiomyocyte hypertrophy via activation of the HIF-1α-TAK1-NF-κB pathway.


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