Transforming growth factor-β1 downregulation of Smad1 gene  expression in rat hepatic stellate cells

Smads are intracellular signaling molecules of the transforming growth factor-β (TGF-β) superfamily that play an important role in the activation of hepatic stellate cells (HSCs) and hepatic fibrosis. Excepting the regulation of Smad7, receptor-regulated Smad gene expression is still unclear. We employed rat HSCs to investigate the expression and regulation of the Smad1 gene, which is a bone morphogenetic protein (BMP) receptor-regulated Smad. We found that the expression and phosphorylation of Smad1 are increased during the activation of HSCs. Moreover, TGF-β significantly inhibits Smad1 gene expression in HSCs in a time- and dose-dependent manner. Furthermore, although both TGF-β1 and BMP2 stimulate the activation of HSCs, they have different effects on HSC proliferation. In conclusion, Smad1 expression and phosphorylation are increased during the activation of HSCs and TGF-β1 significantly inhibits the expression of the Smad1 gene.

Download Full-text

Acetaldehyde stimulates the activation of latent transforming growth factor-β1 and induces expression of the type II receptor of the cytokine in rat cultured hepatic stellate cells

Biochemical Journal ◽

10.1042/bj20020949 ◽

2002 ◽

Vol 368 (3) ◽

pp. 683-693 ◽

Cited By ~ 61

Author(s):

Anping CHEN

Keyword(s):

Gene Expression ◽

Growth Factor ◽

Hepatic Stellate Cells ◽

Transforming Growth Factor ◽

Stellate Cells ◽

Transforming Growth Factor Β1 ◽

Collagen Gene ◽

Type Ii ◽

Underlying Mechanisms ◽

Tgf Β1

Acetaldehyde, the major active metabolite of alcohol, induces the activation of hepatic stellate cells (HSC), leading to over-production of α1(I) collagen and ultimately causing hepatic fibrosis. The underlying mechanisms of this process remain largely unknown. Transforming growth factor-β1 (TGF-β1) is a potent inducer of α1(I) collagen production. Accumulating evidence has shown a potential role for TGF-β1 in alcohol-induced hepatic fibrogenesis. The aims of this study were to determine the effect of acetaldehyde on TGF-β signalling, to elucidate the underlying mechanisms as well as to evaluate its role in expression of α1(I) collagen gene in cultured HSC. It was hypothesized that acetaldehyde activated TGF-β signalling by inducing the expression of elements in the TGF-β signal transduction pathway, which might contribute to α1(I) collagen gene expression in cultured HSC. Initial results revealed that acetaldehyde activated TGF-β signalling in cultured HSC. Additional studies demonstrated that acetaldehyde stimulated the secretion and activation of latent TGF-β1, and induced the expression of the type II TGF-β receptor (Tβ-RII). Further experiments found cis- and trans-activating elements responsible for Tβ-RII gene expression induced by acetaldehyde. Activation of TGF-β signalling by acetaldehyde contributed to α1(I) collagen gene expression in cultured HSC. In summary, this report demonstrated that acetaldehyde stimulated TGF-β signalling by increasing the secretion and activation of latent TGF-β1 as well as by inducing the expression of Tβ-RII in cultured HSC. Results from this report provided a novel insight into mechanisms by which acetaldehyde stimulated the expression of α1(I) collagen in HSC and a better understanding of effects of alcohol (or acetaldehyde) on hepatic fibrogenesis.

Download Full-text

Tanshinone IIA alters the transforming growth factor-β1/Smads pathway in angiotensin II-treated rat hepatic stellate cells

Journal of International Medical Research ◽

10.1177/0300060520926358 ◽

2020 ◽

Vol 48 (6) ◽

pp. 030006052092635

Author(s):

Guo-wei Wei ◽

Ke-yue Li ◽

Ke-li Tang ◽

Cheng-Xian Shi

Keyword(s):

Angiotensin Ii ◽

Growth Factor ◽

Protein Expression ◽

Hepatic Stellate Cells ◽

Transforming Growth Factor ◽

Stellate Cells ◽

Transforming Growth Factor Β1 ◽

Tanshinone Iia ◽

Mrna And Protein Expression ◽

Tgf Β1

Objective To investigate the effects of tanshinone IIA on the transforming growth factor-β1 (TGF-β1)/Smads signaling pathway in angiotensin II-treated hepatic stellate cells (HSCs). Methods HSCs were cultured and treated with angiotensin II (10 μM) or angiotensin II (10 μM) plus tanshinone IIA (3, 10, or 30 μM). Cells were incubated for 48 hours and proliferation was determined with the Cell Counting Kit-8. The relative mRNA expression of TGF-β1, Smad4, and Smad7 was measured by quantitative real-time PCR, and the relative protein expression levels were investigated by western blotting. Results After angiotensin II treatment, cell proliferation was significantly accelerated. Furthermore, both the mRNA and protein expression of TGF-β1 and Smad4 was significantly up-regulated, while the mRNA and protein expression of Smad7 was significantly down-regulated compared with the control cells. Tanshinone IIA inhibited the observed effects of angiotensin II in a concentration-dependent manner, with significant inhibition exerted by tanshinone IIA at 10 and 30 μM. Conclusions Angiotensin II promotes the proliferation of HSCs, possibly by regulating the expression of components along the TGF-β1/Smads signaling pathway. Tanshinone IIA inhibits the angiotensin II-induced activation of this pathway, and may, therefore, have preventive and therapeutic effects in liver fibrosis.

Download Full-text

Stem cells for cardiac regeneration and possible roles of the transforming growth factor-β superfamily

BioMolecular Concepts ◽

10.1515/bmc.2011.049 ◽

2012 ◽

Vol 3 (1) ◽

pp. 99-106 ◽

Cited By ~ 6

Author(s):

Nanako Kawaguchi

Keyword(s):

Stem Cells ◽

Growth Factor ◽

Cell Biology ◽

Transforming Growth Factor ◽

Methyl Cellulose ◽

Transforming Growth Factor Β ◽

Transforming Growth Factor Β1 ◽

Cardiac Stem Cells ◽

Dependent Manner ◽

Tgf Β1

AbstractHeart failure is a leading cause of death worldwide. Studies of stem cell biology are essential for developing efficient treatments. Recently, we established and characterized c-kit-positive cardiac stem cells from the adult rat heart. Using a MethoCult culture system with a methyl-cellulose-based medium, stem-like left-atrium-derived pluripotent cells could be regulated to differentiate into skeletal/cardiac myocytes or adipocytes with almost 100% purity. Microarray and pathway analyses of these cells showed that transforming growth factor-β1 (TGF-β1) and noggin were significantly involved in the differentiation switch. Furthermore, TGF-β1 may act as a regulator for this switch because it simultaneously inhibits adipogenesis and activates myogenesis in a dose-dependent manner. However, the effect of TGF-β varies with developmental stage, dosage, and timing of treatment. In the present review, the findings of recent studies, in particular the use of c-kit-positive cardiac stem cells, are discussed. The effects of the TGF-β superfamily on differentiation, especially on adipogenesis and/or myogenesis, have important implications for future regenerative medicine.

Download Full-text

SMAD and p38 MAPK Signaling Pathways Independently Regulate α1(I) Collagen Gene Expression in Unstimulated and Transforming Growth Factor-β-stimulated Hepatic Stellate Cells

Journal of Biological Chemistry ◽

10.1074/jbc.m409381200 ◽

2005 ◽

Vol 280 (11) ◽

pp. 10055-10064 ◽

Cited By ~ 112

Author(s):

Shigeki Tsukada ◽

John K. Westwick ◽

Kenichi Ikejima ◽

Nobuhiro Sato ◽

Richard A. Rippe

Keyword(s):

Gene Expression ◽

Growth Factor ◽

P38 Mapk ◽

Hepatic Stellate Cells ◽

Transforming Growth Factor ◽

Stellate Cells ◽

Transforming Growth Factor Β ◽

Mapk Signaling ◽

Collagen Gene ◽

Mapk Signaling Pathways

Download Full-text

Integrin αVβ1 Regulates Procollagen I Production through a Non-canonical Transforming Growth Factor β Signaling Pathway in Human Hepatic Stellate Cells

Biochemical Journal ◽

10.1042/bcj20200749 ◽

2021 ◽

Author(s):

Zuoning Han ◽

Yanling Ma ◽

Gary Cao ◽

Zhengping Ma ◽

Ruihua Chen ◽

...

Keyword(s):

Growth Factor ◽

Liver Fibrosis ◽

Hepatic Stellate Cells ◽

Transforming Growth Factor ◽

Specific Inhibitor ◽

Stellate Cells ◽

Transforming Growth Factor Β ◽

Current Data ◽

Human Hscs ◽

Tgf Β1

Hepatic stellate cells (HSCs) are thought to play key roles in the development of liver fibrosis. Extensive evidence has established the concept that αV integrins are involved in the activation of latent transforming growth factor β (TGF-β), a master regulator of the fibrotic signaling cascade. Based on mRNA and protein expression profiling data, we found that αVβ1 integrin is the most abundant member of the αV integrin family in either quiescent or TGF-β1-activated primary human HSCs. Unexpectedly, either a selective αVβ1 inhibitor, Compound 8 (C8), or a pan-αV integrin inhibitor, GSK3008348, decreased TGF-β1-activated procollagen I production in primary human HSCs, in which the role of β1 integrin was confirmed by ITGB1 siRNA. In contrast to an Activin receptor-like kinase 5 (Alk5) inhibitor, C8 and GSK3008348 failed to inhibit TGF-β1 induced SMAD3 and SMAD2 phosphorylation, but inhibited TGF-β-induced phosphorylation of ERK1/2 and STAT3, suggesting that αVβ1 integrin is involved in non-canonical TGF-β signaling pathways. Consistently, ITGB1 siRNA significantly decreased phosphorylation of ERK1/2. Furthermore, a selective inhibitor of MEK1/2 blocked TGF-β1 induced phosphorylation of ERK1/2 and decreased TGF-β1 induced procollagen I production, while a specific inhibitor of STAT3 had no effect on TGF-β1 induced procollagen I production. Taken together, current data indicate that αVβ1 integrin can regulate TGF-β signaling independent of its reported role in activating latent TGF-β. Our data further support that αVβ1 inhibition is a promising therapeutic target for the treatment of liver fibrosis.

Download Full-text

Alteration of protein glycosylation in human hepatic stellate cells activated with transforming growth factor-β1

Journal of Proteomics ◽

10.1016/j.jprot.2012.05.040 ◽

2012 ◽

Vol 75 (13) ◽

pp. 4114-4123 ◽

Cited By ~ 42

Author(s):

Yannan Qin ◽

Yaogang Zhong ◽

Liuyi Dang ◽

Minzhi Zhu ◽

Hanjie Yu ◽

...

Keyword(s):

Growth Factor ◽

Hepatic Stellate Cells ◽

Transforming Growth Factor ◽

Stellate Cells ◽

Transforming Growth Factor Β1 ◽

Protein Glycosylation

Download Full-text

Cellular crosstalk mediated by platelet-derived growth factor BB and transforming growth factor β during hepatic injury activates hepatic stellate cells

Canadian Journal of Physiology and Pharmacology ◽

10.1139/cjpp-2017-0768 ◽

2018 ◽

Vol 96 (8) ◽

pp. 728-741 ◽

Cited By ~ 7

Author(s):

Sowmya Mekala ◽

SubbaRao V. Tulimilli ◽

Ramasatyaveni Geesala ◽

Kanakaraju Manupati ◽

Neha R. Dhoke ◽

...

Keyword(s):

Growth Factor ◽

Hepatic Stellate Cells ◽

Hepg2 Cells ◽

Molecular Mechanisms ◽

Transforming Growth Factor ◽

Stellate Cells ◽

Transforming Growth Factor Β ◽

Platelet Derived Growth Factor ◽

Hepatic Tissue

Apoptotic hepatocytes release factors that activate hepatic stellate cells (HSCs), thereby inducing hepatic fibrosis. In the present study, in vivo and in vitro injury models were established using acetaminophen, ethanol, carbon tetrachloride, or thioacetamide. Histology of hepatotoxicant-induced diseased hepatic tissue correlated with differential expression of fibrosis-related genes. A marked increase in co-staining of transforming growth factor β receptor type II (TGFRIIβ) – desmin or α-smooth muscle actin – platelet-derived growth factor receptor β (PDGFRβ), markers of activated HSCs, in liver sections of these hepatotoxicant-treated mice also depicted an increase in Annexin V – cytokeratin expressing hepatocytes. To understand the molecular mechanisms of disease pathology, in vitro experiments were designed using the conditioned medium (CM) of hepatotoxicant-treated HepG2 cells supplemented to HSCs. A significant increase in HSC proliferation, migration, and expression of fibrosis-related genes and protein was observed, thereby suggesting the characteristics of an activated phenotype. Treating HepG2 cells with hepatotoxicants resulted in a significant increase in mRNA expression of platelet-derived growth factor BB (PDGF-BB) and transforming growth factor β (TGFβ). CM supplemented to HSCs resulted in increased phosphorylation of PDGFRβ and TGFRIIβ along with its downstream effectors, extracellular signal-related kinase 1/2 and focal adhesion kinase. Neutralizing antibodies against PDGF-BB and TGFβ effectively perturbed the hepatotoxicant-treated HepG2 cell CM-induced activation of HSCs. This study suggests PDGF-BB and TGFβ as potential molecular targets for developing anti-fibrotic therapeutics.

Download Full-text