scholarly journals Pharmacological inhibition of autophagy by 3-MA attenuates hyperuricemic nephropathy

2018 ◽  
Vol 132 (21) ◽  
pp. 2299-2322 ◽  
Author(s):  
Jinfang Bao ◽  
Yingfeng Shi ◽  
Min Tao ◽  
Na Liu ◽  
Shougang Zhuang ◽  
...  
Keyword(s):  
Growth Factor ◽  
Signaling Pathways ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Growth Factor Receptor ◽  
Nuclear Factor Κb ◽  
Transforming Growth Factor Β1 ◽  
Renal Tissue ◽  
Tgf Β1

Autophagy has been identified as a cellular process of bulk degradation of cytoplasmic components and its persistent activation is critically involved in the renal damage induced by ureteral obstruction. However, the role and underlying mechanisms of autophagy in hyperuricemic nephropathy (HN) remain unknown. In the present study, we observed that inhibition of autophagy by 3-methyladenine (3-MA) abolished uric acid-induced differentiation of renal fibroblasts to myofibroblasts and activation of transforming growth factor-β1 (TGF-β1), epidermal growth factor receptor (EGFR), and Wnt signaling pathways in cultured renal interstitial fibroblasts. Treatment with 3-MA also abrogated the development of HN in vivo as evidenced by improving renal function, preserving renal tissue architecture, reducing the number of autophagic vacuoles, and decreasing microalbuminuria. Moreover, 3-MA was effective in attenuating renal deposition of extracellular matrix (ECM) proteins and expression of α-smooth muscle actin (α-SMA) and reducing renal epithelial cells arrested at the G2/M phase of cell cycle. Injury to the kidney resulted in increased expression of TGF-β1 and TGFβ receptor I, phosphorylation of Smad3 and TGF-β-activated kinase 1 (TAK1), and activation of multiple cell signaling pathways associated with renal fibrogenesis, including Wnt, Notch, EGFR, and nuclear factor-κB (NF-κB). 3-MA treatment remarkably inhibited all these responses. In addition, 3-MA effectively suppressed infiltration of macrophages and lymphocytes as well as release of multiple profibrogenic cytokines/chemokines in the injured kidney. Collectively, these findings indicate that hyperuricemia-induced autophagy is critically involved in the activation of renal fibroblasts and development of renal fibrosis and suggest that inhibition of autophagy may represent a potential therapeutic strategy for HN.

scholarly journals High-Throughput Screening Assay Identifies Small Molecules Capable of Modulating the BMP-2 and TGF-β1 Signaling Pathway

2016 ◽  
Vol 22 (1) ◽  
pp. 40-50 ◽  
Author(s):  
Corina-Adriana Ghebes ◽  
Jéré van Lente ◽  
Janine Nicole Post ◽  
Daniel B. F. Saris ◽  
Hugo Fernandes
Keyword(s):  
Growth Factor ◽  
Small Molecules ◽  
Signaling Pathways ◽  
High Throughput Screening ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β1 ◽  
Bone Morphogenetic Protein 2 ◽  
Screening Assay ◽  
High Throughput Screening Assay ◽  
Tgf Β1

Modulating the bone morphogenetic protein 2 (BMP-2) and transforming growth factor–β1 (TGF-β1) signaling pathways is essential during tendon/ligament (T/L) healing. Unfortunately, growth factor delivery in situ is far from trivial and, in many cases, the necessary growth factors are not approved for clinical use. Here we used a BMP-2 and a TGF-β1 reporter cell line to screen a library of 1280 Food and Drug Administration–approved small molecules and identify modulators of both signaling pathways. We identified four compounds capable of modulating BMP and TGF signaling on primary human tendon–derived cells (huTCs) and describe their effects on proliferation and differentiation of these cells.

Comparison of Release Profiles of Various Growth Factors from Biodegradable Carriers

1998 ◽  
Vol 530 ◽  
Author(s):  
Y. Tabata ◽  
M. Yamamoto ◽  
Y. Ikada
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β1 ◽  
The Body ◽  
Bone Morphogenetic Protein 2 ◽  
Biodegradable Hydrogel ◽  
Tgf Β1

AbstractA biodegradable hydrogel was prepared by glutaraldehyde crosslinking of acidic gelatin with an isoelectric point (IEP) of 5.0 as a carrier to release basic growth factors on the basis of polyion complexation. Basic fibroblast growth factor (bFGF), transforming growth factor β1 (TGF-β1), and bone morphogenetic protein-2 (BMP-2) were sorbed from their aqueous solution into the dried gelatin hydrogels to prepare respective growth factor-incorporating hydrogels. Under an in vitro non-degradation condition, approximately 20 % of incorporated bFGF and TGF-β1 was released from the hydrogels within initial 40 min, followed by no further release, whereas a large initial release of BMP-2 was observed. After subcutaneous implantation of the gelatin hydrogels incorporating 125I-labeled growth factor in the mouse back, the remaining radioactivity was measured to estimate the in vivo release profile of growth factors. Incorporation into gelatin hydrogels enabled bFGF and TGF-β1 to retain in the body for about 15 days and the retention period well correlated with that of the gelatin hydrogel. Taken together, it is likely that the growth factors ionically complexed with acidic gelatin were released in vivo as a result of hydrogel biodegradation. On the contrary, basic BMP-2 did not ionically interact with acidic gelatin, resulting in no sustained released by the present biodegradable carrier system.

scholarly journals Therapeutic Effects of an Inhibitor of Thioredoxin Reductase on Liver Fibrosis by Inhibiting the Transforming Growth Factor-β1/Smads Pathway

2021 ◽  
Vol 8 ◽  
Author(s):  
Wenxuan Jiao ◽  
Man Bai ◽  
Hanwei Yin ◽  
Jiayi Liu ◽  
Jing Sun ◽  
...  
Keyword(s):  
Growth Factor ◽  
Liver Fibrosis ◽  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Thioredoxin Reductase ◽  
Transforming Growth Factor Β1 ◽  
Therapeutic Effects ◽  
Pathological State ◽  
Tgf Β1

Liver fibrosis is an important stage in the progression of liver injury into cirrhosis or even liver cancer. Hepatic stellate cells (HSCs) are induced by transforming growth factor-β1 (TGF-β1) to produce α-smooth muscle actin (α-SMA) and collagens in liver fibrosis. Butaselen (BS), which was previously synthesized by our group, is an organic selenium compound that exerts antioxidant and tumor cell apoptosis–promoting effects by inhibiting the thioredoxin (Trx)/thioredoxin reductase (TrxR) system. The aim of this study was to investigate the potential effects of BS on liver fibrosis and explore the underlying molecular mechanisms of its action. Liver fibrosis models were established using male BALB/c mice through intraperitoneal injection of CCl4. BS was administered orally once daily at a dose of 36, 90, or 180 mg/kg. Silymarin (Si), which is a drug used for patients with nonalcoholic fatty liver disease and nonalcoholic steatohepatitis, was administered at a dose of 30 mg/kg per day as a control. The action mechanisms of BS against liver fibrosis progression were examined in HSCs. The study revealed that the activity and expression levels of TrxR were elevated in the mouse liver and serum after CCl4-induced liver fibrosis. Oral administration of BS relieved the pathological state of mice with liver fibrosis, showing significant therapeutic effects against liver fibrosis. Moreover, BS not only induced HSC apoptosis but also inhibited the production of α-SMA and collagens by HSCs by downregulating the TGF-β1 expression and blocking the TGF-β1/Smads pathway. The results of the study indicated that BS inhibited liver fibrosis by regulating the TGF-β1/Smads pathway.

scholarly journals Characterization of human PDGFR-β-positive pericytes from IPF and non-IPF lungs

2018 ◽  
Vol 315 (6) ◽  
pp. L991-L1002 ◽  
Author(s):  
Carole L. Wilson ◽  
Sarah E. Stephenson ◽  
Jean Paul Higuero ◽  
Carol Feghali-Bostwick ◽  
Chi F. Hung ◽  
...  
Keyword(s):  
Growth Factor ◽  
Lung Fibrosis ◽  
Transforming Growth Factor ◽  
Human Lung ◽  
Smooth Muscle Actin ◽  
Growth Factor Receptor ◽  
Transforming Growth Factor Β ◽  
Marker Profile ◽  
Molecular Patterns

Pericytes are key regulators of the microvasculature through their close interactions with the endothelium. However, pericytes play additional roles in tissue homeostasis and repair, in part by transitioning into myofibroblasts. Accumulation of myofibroblasts is a hallmark of fibrotic diseases such as idiopathic pulmonary fibrosis (IPF). To understand the contribution and role of pericytes in human lung fibrosis, we isolated these cells from non-IPF control and IPF lung tissues based on expression of platelet-derived growth factor receptor-β (PDGFR-β), a common marker of pericytes. When cultured in a specialized growth medium, PDGFR-β+ cells retain the morphology and marker profile typical of pericytes. We found that IPF pericytes migrated more rapidly and invaded a basement membrane matrix more readily than control pericytes. Exposure of cells to transforming growth factor-β, a major fibrosis-inducing cytokine, increased expression of α-smooth muscle actin and extracellular matrix genes in both control and IPF pericytes. Given that pericytes are uniquely positioned in vivo to respond to danger signals of both systemic and tissue origin, we stimulated human lung pericytes with agonists having pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patterns (DAMPs). Both control and IPF lung pericytes increased expression of proinflammatory chemokines in response to specific PAMPs and DAMPs released from necrotic cells. Our results suggest that control and IPF lung pericytes are poised to react to tissue damage, as well as microbial and fibrotic stimuli. However, IPF pericytes are primed for migration and matrix invasion, features that may contribute to the function of these cells in lung fibrosis.

Transforming growth factor-β1 induces cerebrovascular dysfunction and astrogliosis through angiotensin II type 1 receptor-mediated signaling pathways

2018 ◽  
Vol 96 (5) ◽  
pp. 527-534 ◽  
Author(s):  
Brice Ongali ◽  
Nektaria Nicolakakis ◽  
Xin-Kang Tong ◽  
Clotilde Lecrux ◽  
Hans Imboden ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Angiotensin Ii ◽  
Growth Factor ◽  
Signaling Pathways ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β1 ◽  
Cerebrovascular Reactivity ◽  
Cerebrovascular Dysfunction ◽  
Tgf Β1

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.

scholarly journals Thrombospondin 1 does not activate transforming growth factor β1 in a chemically defined system or in smooth-muscle-cell cultures

2000 ◽  
Vol 350 (1) ◽  
pp. 291-298 ◽  
Author(s):  
David J. GRAINGER ◽  
Emma K. FROW
Keyword(s):  
Cell Culture ◽  
Smooth Muscle ◽  
Growth Factor ◽  
Matrix Metalloproteinase ◽  
Smooth Muscle Cell ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β1 ◽  
Matrix Metalloproteinase 2 ◽  
Tgf Β1

The cytokine transforming growth factor β1 (TGF-β1) is secreted in a latent form that has no known biological activity. The conversion of latent TGF-β1 into its biologically active 25kDa form is thought to be an important step in the regulation of TGF-β activity both in cell culture and in vivo. Thrombospondin (TSP)-1, a 360kDa platelet α-granule and extracellular matrix protein, has been shown to participate in TGF-β1 activation. We have used a chemically defined system to examine the mechanism of TSP-1-mediated TGF-β1 activation. However, the addition of two different preparations of TSP-1 to recombinant small latent TGF-β1 in the test tube resulted in only a very small increase in the proportion of the TGF-β1 able to bind to the TGF-β type II receptor: from 0.1% to a maximum of 0.4%. This small effect was not specific for TSP-1: matrix metalloproteinase 2, tissue inhibitor of matrix metalloproteinase 2 and active plasminogen activator inhibitor 1, but not transglutaminase, human serum albumin or immunoglobulin, had quantitatively similar effects on latent TGF-β1. Furthermore, no change in the activity associated with small latent TGF-β1 was noted in either mink lung epithelial cell or rat aortic smooth-muscle cell culture systems in the presence of TSP-1 (or TSP-1-derived peptides). We conclude that TSP-1, either alone or in the presence of cultured smooth-muscle cells (a cell type known to activate latent TGF-β in vitro and in vivo) is unable to activate latent TGF-β1. Any TSP-mediated activation of TGF-β1 must depend on additional factor(s) not present in our systems.

scholarly journals Interleukin-13 Induces Tissue Fibrosis by Selectively Stimulating and Activating Transforming Growth Factor β1

2001 ◽  
Vol 194 (6) ◽  
pp. 809-822 ◽  
Author(s):  
Chun Geun Lee ◽  
Robert J. Homer ◽  
Zhou Zhu ◽  
Sophie Lanone ◽  
Xiaoman Wang ◽  
...  
Keyword(s):  
Growth Factor ◽  
Serine Protease ◽  
Transforming Growth Factor ◽  
Transgenic Animals ◽  
Transforming Growth Factor Β1 ◽  
Tissue Fibrosis ◽  
Helper Cell Type ◽  
Tgf Β1

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.

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