scholarly journals Hypoxia-inducible factor may induce the development of liver fibrosis in Budd–Chiari syndrome by regulating CD248/endosialin expression: A hypothesis

2018 ◽  
Vol 6 (2) ◽  
pp. 66-69 ◽  
Author(s):  
Ye Tian ◽  
Han Deng ◽  
Lei Han ◽  
Sijun Hu ◽  
Xingshun Qi

AbstractBudd-Chiari syndrome (BCS) leads to the development of liver fibrosis in most of the cases. However, the mechanism of BCS-related liver fibrosis is unclear, and it may be largely different from that induced by chronic viral hepatitis. Hepatic stellate cell (HSC) and its specific marker CD248/endosialin are known to play an important regulatory role in the development of liver fibrosis. Additionally, hypoxia microenvironment and hypoxia-inducible factor (HIF) are involved in the regulation of CD248/endosialin. Therefore, we hypothesize that hypoxia microenvironment which develops due to BCS can regulate the expression of CD248/endosialin in HSC via HIF signaling pathway, which then affects the function of HSC and development of liver fibrosis. To confirm the hypothesis, two major investigations are necessary: (1) in the BCS animal model and clinical studies, the relationship between the severity of liver fibrosis and the expression of HIF and CD248/endosialin in HSC will be explored; and (2) in thein vitrocell system, the effect of hypoxic microenvironment, HIF-1α or HIF-2α, on the expression of CD248/endosialin in HSC will be explored. It will be important to elucidate whether HIF signaling pathway regulates the expression of CD248/endosialin, thereby inducing the development of BCS-related liver fibrosis.

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Shenzong Rao ◽  
Jie Xiang ◽  
Jingsong Huang ◽  
Shangang Zhang ◽  
Min Zhang ◽  
...  

Abstract Background PRC1 (Protein regulator of cytokinesis 1) regulates microtubules organization and functions as a novel regulator in Wnt/β-catenin signaling pathway. Wnt/β-catenin is involved in development of liver fibrosis (LF). We aim to investigate effect and mechanism of PRC1 on liver fibrosis. Methods Carbon tetrachloride (CCl4)-induced mice LF model was established and in vitro cell model for LF was induced by mice primary hepatic stellate cell (HSC) under glucose treatment. The expression of PRC1 in mice and cell LF models was examined by qRT-PCR (quantitative real-time polymerase chain reaction), western blot and immunohistochemistry. MTT assay was used to detect cell viability, and western blot to determine the underlying mechanism. The effect of PRC1 on liver pathology was examined via measurement of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and hydroxyproline, as well as histopathological analysis. Results PRC1 was up-regulated in CCl4-induced mice LF model and activated HSC. Knockdown of PRC1 inhibited cell viability and promoted cell apoptosis of activated HSC. PRC1 expression was regulated by Wnt3a signaling, and PRC1 could regulate downstream β-catenin activation. Moreover, PRC1 could activate glioma-associated oncogene homolog 1 (GLI1)-dependent osteopontin expression to participate in LF. Adenovirus-mediated knockdown of PRC1 in liver attenuated LF and reduced collagen deposition. Conclusions PRC1 aggravated LF through regulating Wnt/β-catenin mediated GLI1-dependent osteopontin expression, providing a new potential therapeutic target for LF treatment.


2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Min Liu ◽  
Youwei Xu ◽  
Xu Han ◽  
Lianhong Yin ◽  
Lina Xu ◽  
...  

Abstract The present work aimed to investigate the activities and underlying mechanisms of dioscin against alcoholic liver fibrosis (ALF). In vivo liver fibrosis in mice was induced by an alcoholic liquid diet and in vitro studies were performed on activated HSC-T6 and LX2 cells treated with lipopolysaccharide. Our results showed that dioscin significantly attenuated hepatic stellate cells (HSCs) activation, improved collagen accumulation and attenuated inflammation through down-regulating the levels of myeloid differentiation factor 88 (MyD88), nuclear factor κB (NF-κB), interleukin (IL)-1, IL-6 and tumour necrosis factor-α by decreasing Toll-like receptor (TLR)4 expression both in vivo and in vitro. TLR4 overexpression was also decreased by dioscin, leading to the markedly down-regulated levels of MyD88, NF-κB, transforming growth factor-β1 (TGF-β1), α-smooth muscle actin (α-SMA) and type I collagen (COL1A1) in cultured HSCs. Suppression of cellular MyD88 by ST2825 or abrogation of NF-κB by pyrrolidine dithiocarbamate eliminated the inhibitory effects of dioscin on the levels of TGF-β1, α-SMA and COL1A1. In a word, dioscin exhibited potent effects against ALF via altering TLR4/MyD88/NF-κB signaling pathway, which provided novel insights into the mechanisms of this compound as an antifibrogenic candidate for the treatment of ALF in the future.


QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Mohammed F Montasser ◽  
Eman M Barakat ◽  
Mohamed S Ghazy ◽  
Sara M Abdelhakam ◽  
Hend E Ebada ◽  
...  

Abstract Aim of the work To test the reliability of fibroscan in detection of fibrosis in patients with Budd Chiari syndrome before and after endovascular intervention (after elimination of hepatic congestion). Background transient elastography (TE) is a noninvasive methodology that has been used to monitor liver stiffness in patients with chronic viral hepatitis. One of the limitations for accurate assessment of liver fibrosis by TE is the liver congestion. Liver congestion can result from Budd Chiari syndrome (BCS).The treatment of BCS is through restoring the flow of the blood between the portal vein to the inferior vena cava, which will lead to decongestion of the liver.TE, will be tested after liver decongestion for proper detection of liver fibrosis. Patients and methods This was a prospective cohort study conducted on 25 Egyptian patients with confirmed diagnosis of primary Budd-Chiari Syndrome (BCS) in the period from June 2017 to September 2019. TE was performed three days before endovascular intervention and three months after it. Liver biopsy was taken during the intervention for assessment of METAVIR score. Comparison was done between TE assessments before and after intervention in detection of the degree of liver fibrosis in comparison to METAVIR score measured in liver biopsy. Results FVLM was the most common hypercoagulable cause in the involved patients. There was significant drop in Liver Stiffness Measurements (LSM) measured three months post-intervention indicating improvement of liver fibrosis after relieving liver congestion but still not correlated to the METAVIR scores measured in the liver biopsy. Conclusion Liver congestion has high impact on Liver stiffness measurement giving overestimation which improves significantly after decongestion of the liver by the endovascular intervention.


Gut ◽  
2021 ◽  
pp. gutjnl-2021-325065
Author(s):  
Chen-Ting Hung ◽  
Tung-Hung Su ◽  
Yen-Ting Chen ◽  
Yueh-Feng Wu ◽  
You-Tzung Chen ◽  
...  

Background and objectivesLiver fibrosis (LF) occurs following chronic liver injuries. Currently, there is no effective therapy for LF. Recently, we identified thioredoxin domain containing 5 (TXNDC5), an ER protein disulfide isomerase (PDI), as a critical mediator of cardiac and lung fibrosis. We aimed to determine if TXNDC5 also contributes to LF and its potential as a therapeutic target for LF.DesignHistological and transcriptome analyses on human cirrhotic livers were performed. Col1a1-GFPTg, Alb-Cre;Rosa26-tdTomato and Tie2-Cre/ERT2;Rosa26-tdTomato mice were used to determine the cell type(s) where TXNDC5 was induced following liver injury. In vitro investigations were conducted in human hepatic stellate cells (HSCs). Col1a2-Cre/ERT2;Txndc5fl/fl (Txndc5cKO) and Alb-Cre;Txndc5fl/fl (Txndc5Hep-cKO) mice were generated to delete TXNDC5 in HSCs and hepatocytes, respectively. Carbon tetrachloride treatment and bile duct ligation surgery were employed to induce liver injury/fibrosis in mice. The extent of LF was quantified using histological, imaging and biochemical analyses.ResultsTXNDC5 was upregulated markedly in human and mouse fibrotic livers, particularly in activated HSC at the fibrotic foci. TXNDC5 was induced by transforming growth factor β1 (TGFβ1) in HSCs and it was both required and sufficient for the activation, proliferation, survival and extracellular matrix production of HSC. Mechanistically, TGFβ1 induces TXNDC5 expression through increased ER stress and ATF6-mediated transcriptional regulation. In addition, TXNDC5 promotes LF by redox-dependent JNK and signal transducer and activator of transcription 3 activation in HSCs through its PDI activity, activating HSCs and making them resistant to apoptosis. HSC-specific deletion of Txndc5 reverted established LF in mice.ConclusionsER protein TXNDC5 promotes LF through redox-dependent HSC activation, proliferation and excessive extracellular matrix production. Targeting TXNDC5, therefore, could be a potential novel therapeutic strategy to ameliorate LF.


2018 ◽  
Vol 51 (5) ◽  
pp. 2111-2122 ◽  
Author(s):  
Yi-Bing Hu ◽  
Xiao-Ting Ye ◽  
Qing-Qing Zhou ◽  
Rong-Quan Fu

Background/Aims: Sestrin 2 is associated with the pathophysiology of several diseases. The aim of this study was to investigate the effects and potential mechanisms of Sestrin 2 in rat hepatic stellate cells (HSCs) during liver fibrogenesis. Methods: In this study, Sestrin 2 protein expression was detected in rat HSC-T6 cells challenged with transforming growth factor-β (TGF-β) and in mice treated with carbon tetrachloride (CCl4), a well-known model of hepatic fibrosis. Next, HSC-T6 cells and fibrotic mice were transfected with lentivirus. The mRNA expression levels of markers of liver fibrosis [alpha-smooth muscle actin (α-SMA) and collagen 1A1 (Col1A1)] were analyzed by quantitative reverse transcription–polymerase chain reaction (RT-PCR). Cell death and proliferation were evaluated by the MTT assay, and biochemical markers of liver damage in serum [alanine transaminase (ALT) and aspartate transaminase (AST)] were also measured using a biochemical analyzer. Histopathological examination was used to evaluate the degree of liver fibrosis, and protein expression [phospho-adenosine monophosphate-activated protein kinase (p-AMPK), AMPK, phospho-mammalian target of rapamycin (p-mTOR), and mTOR] was determined by western blotting. Results: We found that Sestrin 2 was elevated in both the HSC-T6 cell and hepatic fibrosis models. In vitro, overexpression of Sestrin 2 attenuated the mRNA levels of α-SMA and Col1A1, suppressed α-SMA protein expression, and modulated HSC-T6 cell proliferation. In vivo, overexpression of Sestrin 2 reduced the ALT and AST levels as well as the α-SMA and Col1A1 protein expression in the CCl4 model of liver fibrosis. Moreover, the degree of liver fibrosis was ameliorated. Interestingly, overexpression of Sestrin 2 increased p-AMPK but decreased p-mTOR protein expression. Conclusion: Our findings indicate that Sestrin 2 may attenuate the activation of HSCs and ameliorate liver fibrosis, most likely via upregulation of AMPK phosphorylation and suppression of the mTOR signaling pathway.


2018 ◽  
Vol 51 (3) ◽  
pp. 1389-1398 ◽  
Author(s):  
Lili Zhu ◽  
Tingting Ren ◽  
Zixin Zhu ◽  
Mingliang  Cheng ◽  
Qiuju Mou ◽  
...  

Background/Aims: Hepatic stellate cells (HSCs) are the primary cell type responsible for liver fibrosis. Our study proved that thymosin beta 4 (Tβ4) has anti-fibrogenic effects in HSCs through PI3K/AKT pathway. However, the underlying mechanisms are not fully elucidated. Circular RNAs (circRNAs) play important roles in fine-tuning gene expression and are often deregulated in cancers. However, the expression profile and clinical significance of in liver fibrosis is still unknown. Therefore, we hypothesize that Tβ4 influences circRNAs in liver fibrosis. Methods: Circular RNA microarray was conducted to identify Tβ4-related circRNAs. Pathway analysis and miRNA response elements analysis was conducted to predict the potential roles of differentially expressed circRNAs in liver fibrosis. CCK8 assays and flow cytometric assays were conducted to clarify the role of circRNA in liver fibrosis. Bioinformatics analysis and in vitro experiments were conducted to clarify the mechanism of circRNA-mediated gene regulation in liver fibrosis. Results: A total of 644 differentially expressed circRNAs were identified between the Tβ4-depleted LX-2 cells and the control LX2 cells. The expression of circRNA-0067835 was significantly increased in the Tβ4-depleted LX-2 cells compared with control. Knockdown of circRNA-0067835 observably decreased LX-2 cell proliferation by causing G1 arrest and promoting apoptosis. Bioinformatics online programs predicted that circRNA-0067835 acted as miR-155 sponge to regulate FOXO3a expression, which was validated using luciferase reporter assay. Conclusion: Our experiments showed that circRNA-0067835 regulated liver fibrosis progression by acting as a sponge of miR-155 to promote FOXO3a expression, indicating that circRNA-0067835 may serve as a potential therapeutic target for patients with liver fibrosis.


2021 ◽  
Author(s):  
Yan Lin ◽  
Mingjing Wang ◽  
Zhen Xiao ◽  
Zhiyan Jiang

Abstract Adenoid hypertrophy (AH) can cause harmful effects on untreated children, which include mouth breathing, chronic intermittent hypoxia, sleep disordered breathing (SDB), and even some behavioral problems. However, the molecular mechanisms underlying this pathophysiological process have remained poorly understood. In this study, with use of a variety of biochemical approaches including gene silencing and transiently ectopic protein expression, we examined the molecular effectors involved in this process in an in vitro model of human tonsil epithelial cells (HTECs). We found that a hypoxic condition caused a dramatic upregulation of SUMO-1 expression, a member of the ubiquitin-like protein family, which in turn stabilized hypoxia-inducible factor (HIF)-1α by sumoylating this HIF subunit and thus preventing its ubiquitination and degradation in HTECs. We also found that activating HIF-1α promoted permeability of HTEC cells as well as production and secretion of a variety of proinflammatory cytokines including IL-6, IL-8, and TNF-α, and pro-angiogenic growth factor VEGF. Furthermore, our data showed that hypoxia-induced inflammation was markedly inhibited by M2 macrophages that possess potent anti-inflammatory function. Our results suggest that selectively inhibiting the SUMO-1-HIF-1α signaling pathway leads to inflammatory responses in human tonsil epithelial cells, which might be a novel therapeutic approach for managing hypoxia-induced SDB resulting from AH.


Author(s):  
Enis Kostallari ◽  
Bo Wei ◽  
Delphine Sicard ◽  
Jiahui Li ◽  
Shawna A. Cooper ◽  
...  

The fibrogenic wound-healing response in liver increases stiffness. Stiffness mechano-transduction in turn amplifies fibrogenesis. Here, we aimed to understand the distribution of stiffness in fibrotic liver, how it impacts hepatic stellate cell (HSC) heterogeneity and identify mechanisms by which stiffness amplifies fibrogenic responses. Magnetic resonance elastography and atomic force microscopy demonstrated a heterogenous distribution of liver stiffness at macroscopic and microscopic levels, respectively, in a carbon tetrachloride (CCl4) mouse model of liver fibrosis as compared to controls. High stiffness was mainly attributed to extracellular matrix dense areas. To identify a stiffness-sensitive HSC sub-population, we performed scRNA-seq on primary HSCs derived from healthy versus CCl4-treated mice. A sub-cluster of HSCs was matrix-associated with the most upregulated pathway in this sub-population being focal adhesion signaling, including a specific protein termed four and a half LIM domains protein 2 (FHL2). In vitro, FHL2 expression was increased in primary human HSCs cultured on stiff matrix as compared to HSCs on soft matrix. Moreover, FHL2 knockdown inhibited fibronectin and collagen 1 expression, whereas its overexpression promoted matrix production. In summary, we demonstrate stiffness heterogeneity at the whole organ, lobular, and cellular level which drives an amplification loop of fibrogenesis through specific focal adhesion molecular pathways.


Cells ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 1003 ◽  
Author(s):  
Lambrecht ◽  
Verhulst ◽  
Reynaert ◽  
van Grunsven

Background: The current diagnosis of early-stage liver fibrosis often relies on a serological or imaging-based evaluation of the stage of fibrosis, sometimes followed by an invasive liver biopsy procedure. Novel non-invasive experimental diagnostic tools are often based on markers of hepatocyte damage, or changes in liver stiffness and architecture, which are late-stage characteristics of fibrosis progression, making them unsuitable for the diagnosis of early-stage liver fibrosis. miRNAs control hepatic stellate cell (HSC) activation and are proposed as relevant diagnostic markers. Methods: We investigated the possibility of circulating miRNAs, which we found to be dysregulated upon HSC activation, to mark the presence of significant liver fibrosis (F ≥ 2) in patients with chronic alcohol abuse, chronic viral infection (HBV/HCV), and non-alcoholic fatty liver disease (NAFLD). Results: miRNA-profiling identified miRNA-451a, miRNA-142-5p, Let-7f-5p, and miRNA-378a-3p to be significantly dysregulated upon in vitro HSC activation, and to be highly enriched in their extracellular vesicles, suggesting their potential use as biomarkers. Analysis of the plasma of patients with significant liver fibrosis (F ≥ 2) and no or mild fibrosis (F = 0-1), using miRNA-122-5p and miRNA-29a-3p as positive control, found miRNA-451a, miRNA-142-5p, and Let-7f-5p, but not miRNA-378a-3p, able to distinguish between the two patient populations. Using logistic regression analysis, combining all five dysregulated circulating miRNAs, we created the miRFIB-score with a predictive value superior to the clinical scores Fibrosis-4 (Fib-4), aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio, and AST to platelet ratio index (APRI). The combination of the miRFIB-score with circulating PDGFRβ-levels further increased the predictive capacity for the diagnosis of significant liver fibrosis. Conclusions: The miRFIB- and miRFIBp-scores are accurate tools for the diagnosis of significant liver fibrosis in a heterogeneous patient population.


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