scholarly journals Antifibrotic Effect of Marine Ovothiol in an In Vivo Model of Liver Fibrosis

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Mariarita Brancaccio ◽  
Giuseppe D’Argenio ◽  
Vincenzo Lembo ◽  
Anna Palumbo ◽  
Immacolata Castellano
Keyword(s):  
Liver Fibrosis ◽  
Matrix Protein ◽  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Extracellular Matrix Protein ◽  
In Vivo Model ◽  
Protein Accumulation ◽  
Antifibrotic Effect

Liver fibrosis is a complex process caused by chronic hepatic injury, which leads to an excessive increase in extracellular matrix protein accumulation and fibrogenesis. Several natural products, including sulfur-containing compounds, have been investigated for their antifibrotic effects; however, the molecular mechanisms underpinning their action are partially still obscure. In this study, we have investigated for the first time the effect of ovothiol A, π-methyl-5-thiohistidine, isolated from sea urchin eggs on an in vivo murine model of liver fibrosis. Mice were intraperitoneally injected with carbon tetrachloride (CCl4) to induce liver fibrosis and treated with ovothiol A at the dose of 50 mg/kg 3 times a week for 2 months. Treatment with ovothiol A caused a significant reduction of collagen fibers as observed by histopathological changes and serum parameters compared to mice treated with control solution. This antifibrotic effect was associated to the decrease of fibrogenic markers involved in liver fibrosis progression, such as the transforming growth factor (TGF-β), the α-smooth muscle actin (α-SMA), and the tissue metalloproteinases inhibitor (TIMP-1). Finally, we provided evidence that the attenuation of liver fibrosis by ovothiol A treatment can be regulated by the expression and activity of the membrane-bound γ-glutamyl-transpeptidase (GGT), which is a key player in maintaining intracellular redox homoeostasis. Overall, these findings indicate that ovothiol A has significant antifibrotic properties and can be considered as a new marine drug or dietary supplement in potential therapeutic strategies for the treatment of liver fibrosis.

scholarly journals mTOR inhibitors potentially reduce TGF-β2-induced fibrogenic changes in trabecular meshwork cells

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nozomi Igarashi ◽  
Megumi Honjo ◽  
Makoto Aihara
Keyword(s):  
Trabecular Meshwork ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Mtor Inhibitors ◽  
In Vivo Model ◽  
Type I ◽  
Fibrotic Response ◽  
Alpha Smooth Muscle Actin

AbstractWe examined the effects of mTOR inhibitors on the fibrotic response induced by transforming growth factor-beta2 (TGF-β2) in cultured human trabecular meshwork (hTM) cells. TGF-β2-induced expression of fibronectin, collagen type I, alpha 1 chain (COL1A1), and alpha-smooth muscle actin (αSMA) in hTM cells was examined in the presence or absence of mTOR inhibitors using quantitative real-time polymerase chain reaction, Western blotting, and immunohistochemistry. The migration rates of hTM cells were examined in the presence of TGF-β2 with or without mTOR inhibitors. An in vitro study showed that the expression of fibronectin, COL1A1, and αSMA was upregulated by TGF-β2 treatment of hTM cells; such upregulation was significantly suppressed by mTOR inhibitors. The inhibitors significantly reduced the migration rate of TGF-β2-stimulated hTM cells. mTOR inhibitors may usefully reduce the fibrotic response of hTM cells and we may have to explore if it is also effective in in vivo model.

scholarly journals Direct observation of structure and dynamics during phase separation of an elastomeric protein

2017 ◽  
Vol 114 (22) ◽  
pp. E4408-E4415 ◽  
Author(s):  
Sean E. Reichheld ◽  
Lisa D. Muiznieks ◽  
Fred W. Keeley ◽  
Simon Sharpe
Keyword(s):  
Phase Separation ◽  
Matrix Protein ◽  
Molecular Mechanisms ◽  
Bulk Water ◽  
Extracellular Matrix Protein ◽  
Elastic Fibers ◽  
Cross Linking ◽  
Structure And Dynamics ◽  
Chemical Cross Linking

Despite its growing importance in biology and in biomaterials development, liquid–liquid phase separation of proteins remains poorly understood. In particular, the molecular mechanisms underlying simple coacervation of proteins, such as the extracellular matrix protein elastin, have not been reported. Coacervation of the elastin monomer, tropoelastin, in response to heat and salt is a critical step in the assembly of elastic fibers in vivo, preceding chemical cross-linking. Elastin-like polypeptides (ELPs) derived from the tropoelastin sequence have been shown to undergo a similar phase separation, allowing formation of biomaterials that closely mimic the material properties of native elastin. We have used NMR spectroscopy to obtain site-specific structure and dynamics of a self-assembling elastin-like polypeptide along its entire self-assembly pathway, from monomer through coacervation and into a cross-linked elastic material. Our data reveal that elastin-like hydrophobic domains are composed of transient β-turns in a highly dynamic and disordered chain, and that this disorder is retained both after phase separation and in elastic materials. Cross-linking domains are also highly disordered in monomeric and coacervated ELP3 and form stable helices only after chemical cross-linking. Detailed structural analysis combined with dynamic measurements from NMR relaxation and diffusion data provides direct evidence for an entropy-driven mechanism of simple coacervation of a protein in which transient and nonspecific intermolecular hydrophobic contacts are formed by disordered chains, whereas bulk water and salt are excluded.

scholarly journals PASS-Predicted Hepatoprotective Activity ofCaesalpinia sappanin Thioacetamide-Induced Liver Fibrosis in Rats

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Farkaad A. Kadir ◽  
Normadiah M. Kassim ◽  
Mahmood Ameen Abdulla ◽  
Behnam Kamalidehghan ◽  
Fatemeh Ahmadipour ◽  
...  
Keyword(s):  
Liver Fibrosis ◽  
Transforming Growth Factor ◽  
Antioxidant Activities ◽  
Smooth Muscle Actin ◽  
Immunohistochemical Analysis ◽  
Hepatoprotective Activity ◽  
Nuclear Antigen ◽  
Sprague Dawley ◽  
Liver Fibrogenesis

The antifibrotic effects of traditional medicinal herbCaesalpinia sappan(CS) extract on liver fibrosis induced by thioacetamide (TAA) and the expression of transforming growth factorβ1 (TGF-β1),α-smooth muscle actin (αSMA), and proliferating cell nuclear antigen (PCNA) in rats were studied. A computer-aided prediction of antioxidant and hepatoprotective activities was primarily performed with the Prediction Activity Spectra of the Substance (PASS) Program. Liver fibrosis was induced in male Sprague Dawley rats by TAA administration (0.03% w/v) in drinking water for a period of 12 weeks. Rats were divided into seven groups: control, TAA, Silymarin (SY), and CS 300 mg/kg body weight and 100 mg/kg groups. The effect of CS on liver fibrogenesis was determined by Masson’s trichrome staining, immunohistochemical analysis, and western blotting.In vivodetermination of hepatic antioxidant activities, cytochrome P450 2E1 (CYP2E1), and matrix metalloproteinases (MPPS) was employed. CS treatment had significantly increased hepatic antioxidant enzymes activity in the TAA-treated rats. Liver fibrosis was greatly alleviated in rats when treated with CS extract. CS treatment was noted to normalize the expression of TGF-β1,αSMA, PCNA, MMPs, and TIMP1 proteins. PASS-predicted plant activity could efficiently guide in selecting a promising pharmaceutical lead with high accuracy and required antioxidant and hepatoprotective properties.

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 Loss of STAT5 causes liver fibrosis and cancer development through increased TGF-β and STAT3 activation

2009 ◽  
Vol 206 (4) ◽  
pp. 819-831 ◽  
Author(s):  
Atsushi Hosui ◽  
Akiko Kimura ◽  
Daisuke Yamaji ◽  
Bing-mei Zhu ◽  
Risu Na ◽  
...  
Keyword(s):  
Liver Fibrosis ◽  
Messenger Rna ◽  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
Null Mouse ◽  
Protein Levels ◽  
Β Protein ◽  
Ccl4 Treatment ◽  
The Stability

The molecular mechanisms underlying the development of hepatocellular carcinoma are not fully understood. Liver-specific signal transducer and activator of transcription (STAT) 5A/B–null mice (STAT5-LKO) were treated with carbon tetrachloride (CCl4), and histological analyses revealed liver fibrosis and tumors. Transforming growth factor (TGF)–β levels and STAT3 activity were elevated in liver tissue from STAT5-LKO mice upon CCl4 treatment. To define the molecular link between STAT5 silencing and TGF-β up-regulation, as well as STAT3 activation, we examined STAT5-null mouse embryonic fibroblasts and primary hepatocytes. These cells displayed elevated TGF-β protein levels, whereas messenger RNA levels remained almost unchanged. Protease inhibitor studies revealed that STAT5 deficiency enhanced the stability of mature TGF-β. Immunoprecipitation and immunohistochemistry analyses demonstrated that STAT5, through its N-terminal sequences, could bind to TGF-β and that retroviral-mediated overexpression of STAT5 decreased TGF-β levels. To confirm the in vivo significance of the N-terminal domain of STAT5, we treated mice that expressed STAT5 lacking the N terminus (STAT5-ΔN) with CCl4. STAT5-ΔN mice developed CCl4-induced liver fibrosis but no tumors. In conclusion, loss of STAT5 results in elevated TGF-β levels and enhanced growth hormone–induced STAT3 activity. We propose that a deregulated STAT5–TGF-β–STAT3 network contributes to the development of chronic liver disease.

scholarly journals Galectin-3 modulates phagocytosis-induced stellate cell activation and liver fibrosis in vivo

2012 ◽  
Vol 302 (4) ◽  
pp. G439-G446 ◽  
Author(s):  
Joy X. Jiang ◽  
Xiangling Chen ◽  
Daniel K. Hsu ◽  
Kornelia Baghy ◽  
Nobuko Serizawa ◽  
...  
Keyword(s):  
Liver Fibrosis ◽  
Cell Activation ◽  
Transforming Growth Factor ◽  
Stellate Cell ◽  
Smooth Muscle Actin ◽  
In Vivo Studies ◽  
Enzyme Linked Immunosorbent Assay ◽  
Apoptotic Cells ◽  
Galectin 3

Hepatic stellate cells (HSC), the key fibrogenic cells of the liver, transdifferentiate into myofibroblasts upon phagocytosis of apoptotic hepatocytes. Galectin-3, a β-galactoside-binding lectin, is a regulator of the phagocytic process. In this study, our aim was to study the mechanism by which extracellular galectin-3 modulates HSC phagocytosis and activation. The role of galectin-3 in engulfment was evaluated by phagocytosis and integrin binding assays in primary HSC. Galectin-3 expression was studied by real-time PCR and enzyme-linked immunosorbent assay, and in vivo studies were done in wild-type and galectin-3−/− mice. We found that HSC from galectin-3−/− mice displayed decreased phagocytic activity, expression of transforming growth factor-β1, and procollagen α1(I). Recombinant galectin-3 reversed this defect, suggesting that extracellular galectin-3 is required for HSC activation. Galectin-3 facilitated the αvβ3 heterodimer-dependent binding, indicating that galectin-3 modulates HSC phagocytosis via cross-linking this integrin and enhancing the tethering of apoptotic cells. Blocking integrin αvβ3 resulted in decreased phagocytosis. Galectin-3 expression and release were induced in active HSC engulfing apoptotic cells, and this was mediated by the nuclear factor-κB signaling. The upregulation of galectin-3 in active HSC was further confirmed in vivo in bile duct-ligated (BDL) rats. Galectin-3−/− mice displayed significantly decreased fibrosis, with reduced expression of α-smooth muscle actin and procollagen α1(I) following BDL. In summary, extracellular galectin-3 plays a key role in liver fibrosis by mediating HSC phagocytosis, activation, and subsequent autocrine and paracrine signaling by a feedforward mechanism.

scholarly journals The Effects of Platelet-Derived Growth Factor Antagonism in Experimental Glomerulonephritis Are Independent of the Transforming Growth Factor–β System

2002 ◽  
Vol 13 (3) ◽  
pp. 658-667 ◽  
Author(s):  
Tammo Ostendorf ◽  
Uta Kunter ◽  
Claudia van Roeyen ◽  
Steven Dooley ◽  
Nebojsa Janjic ◽  
...  
Keyword(s):  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Matrix Protein ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β ◽  
Platelet Derived Growth Factor ◽  
Renal Diseases ◽  
Protein Accumulation ◽  
Type I

ABSTRACT. Platelet-derived growth factor B-chain (PDGF-B)– and transforming growth factor beta (TGF-β)–mediated accumulation of extracellular matrix proteins contributes to many progressive renal diseases. In vivo, specific antagonism of either PDGF-B or TGF-β in experimental mesangioproliferative glomerulonephritis resulted in an almost complete inhibition of matrix protein accumulation, which suggests an interaction between signaling pathways of these two growth factors. Because nothing is known on the nature of this possible interaction, PDGF-B was antagonized in the rat anti–Thy 1.1 model of glomerulonephritis by use of specific aptamers and its effects on the TGF-β system were investigated. Antagonism of PDGF-B led to a significant reduction of glomerular matrix accumulation compared with scrambled aptamer-treated nephritic controls. PDGF-B antagonism had no effect on the overexpression of glomerular TGF-β mRNA, TGF-β protein, or the expression of TGF-β receptor type I and II mRNA. By immunohistology, it was possible to detect overexpression of the cytoplasmic TGF-β signaling molecules Smad2 (agonistic) and Smad7 (antagonistic) in glomeruli of nephritic control rats which peaked on day 7 after disease induction, i.e., the peak of mesangial cell proliferation in this model. However, immunohistology and Western blot analysis again revealed no difference in the glomerular expression of both Smad proteins between PDGF-B antagonized and nonantagonized nephritic animals. In addition, no difference in the glomerular expression of phosphorylated Smad2 (P-Smad2) was detected between the differently treated nephritic groups. These observations suggest that the effects of PDGF-B antagonism are independent of TGF-β in mesangioproliferative glomerulonephritides.

Cryptolepine derivative-6h inhibits liver fibrosis in TGF-β1-induced HSC-T6 cells by targeting the Shh pathway

2016 ◽  
Vol 94 (9) ◽  
pp. 987-995 ◽  
Author(s):  
Ying-Hua He ◽  
Zeng Li ◽  
Ming-Ming Ni ◽  
Xing-Yan Zhang ◽  
Ming-Fang Li ◽  
...  
Keyword(s):  
Liver Fibrosis ◽  
Transforming Growth Factor Beta ◽  
Molecular Mechanisms ◽  
Type I Collagen ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Type I ◽  
African Countries ◽  
Shh Pathway ◽  
Tgf Β1

Liver fibrosis is a worldwide problem with a significant morbidity and mortality. Cryptolepis sanguinolenta (family Periplocaceae) is widely used in West African countries for the treatment of malaria, as well as for some other diseases. However, the role of C. sanguinolenta in hepatic fibrosis is still unknown. It has been reported that Methyl-CpG binding protein 2 (MeCP2) had a high expression in liver fibrosis and played a central role in its pathobiology. Interestingly, we found that a cryptolepine derivative (HZ-6h) could inhibit liver fibrosis by reducing MeCP2 expression, as evidenced by the dramatic downregulation of α-smooth muscle actin (α-SMA) and type I collagen alpha-1 (Col1α1) in protein levels in vitro. Meanwhile, we also found that HZ-6h could reduce the cell viability and promote apoptosis of hepatic stellate cells (HSCs) treated with transforming growth factor beta 1(TGF-β1). Then, we investigated the potential molecular mechanisms and found that HZ-6h blocked Shh signaling in HSC-T6 cells, resulting in the decreased protein expression of Patched-1 (PTCH-1), Sonic hedgehog (Shh), and glioma-associated oncogene homolog 1 (GLI1). In short, these results indicate that HZ-6h inhibits liver fibrosis by downregulating MeCP2 through the Shh pathway in TGF-β1-induced HSC-T6 cells.

Effect of Age and Frequency on Intervertebral Disc Cell Response to Dynamic Compression

2007 ◽  
Author(s):  
Casey L. Korecki ◽  
Catherine K. Kuo ◽  
Rocky S. Tuan ◽  
James C. Iatridis
Keyword(s):  
Extracellular Matrix ◽  
Intervertebral Disc ◽  
Mechanical Stimulation ◽  
Matrix Protein ◽  
Dynamic Compression ◽  
Model Systems ◽  
Extracellular Matrix Protein ◽  
Tissue Culture Cell ◽  
Protein Accumulation

The intervertebral disc (IVD) is a unique orthopaedic tissue consisting of at least two cell types: fibroblast-like annulus fibrosus (AF) cells and chondrocyte-like nucleus pulposus (NP) cells. Culture of cells in 3D gel matrices (such as alginate or agarose), maintains the normal morphology and ECM molecule production of chondrocytes for extended periods of time and also allows the application of various forms of mechanical stimulation, such as hydrostatic or compressive loading. In vivo studies have shown IVD cells to be responsive to frequency, duration, and amplitude of mechanical load [1]. IVD literature on mechanobiology uses varying methodologies to apply dynamic loads (compression, hydrostatic forces), with different times of mechanical stimulation, differences in model systems (in vivo, tissue culture, cell culture), species, and ages, and an optimal loading protocol to stimulate extracellular matrix protein accumulation is unknown. The overall goal of this work is to evaluate the potential, and perhaps even feasibility, of mechanical stimulation for extracellular matrix (ECM) regeneration using intervertebral disc cells. Also of interest is whether cells from mature tissue are capable of serving as a potential cell source for future IVD regeneration [2,3].

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