scholarly journals Raf Kinase Inhibitory Protein Down-Expression Exacerbates Hepatic Fibrosis In Vivo and In Vitro

2016 ◽  
Vol 40 (1-2) ◽  
pp. 49-61 ◽  
Author(s):  
Quanfang Huang ◽  
Chunhong Liang ◽  
Ling Wei ◽  
Jinlan Nie ◽  
Shengjuan Lu ◽  
...  

Background/Aims: Raf kinase inhibitory protein (RKIP) is closely associated with numerous tumors and participates in their development through regulating the growth, apoptosis, invasion and metastasis of tumor cells. However, the role of RKIP in chronic liver injury and particularly in liver fibrosis is still unclear. Methods: In the present study, hepatic fibrosis was induced by porcine serum (PS) in rats and primary hepatic stellate cells (HSCs) were isolated from rat livers. Moreover, locostatin was used to interfere with RKIP expression. Results: RKIP expression was significantly inhibited by locostatin in both liver tissues of rats and primary HSCs. Down-regulating RKIP expression resulted in serious liver injury, extensive accumulation of collagen, and significant increase in the levels of ALT, AST and TNF-α during liver fibrosis in rats. Moreover, down-regulating RKIP significantly promoted HSCs proliferation and colony formation in vitro. Reduced RKIP significantly increased the production of collagen and the level of α-SMA as well as the expression of MMP-1 and MMP-2 in both liver tissues and primary HSCs. Furthermore, down-regulating RKIP promoted the activation of the ERK and TLR4 signaling pathways. Conclusion: Our findings clearly indicate an inverse correlation between RKIP level and the degree of the liver injury and fibrosis. The decrease in RKIP expression may exacerbate chronic liver injury and liver fibrosis.

2021 ◽  
Vol 22 (4) ◽  
pp. 2041
Author(s):  
Ji Hye Yang ◽  
Sae Kwang Ku ◽  
IL Je Cho ◽  
Je Hyeon Lee ◽  
Chang-Su Na ◽  
...  

Hepatic fibrosis occurs when liver tissue becomes scarred from repetitive liver injury and inflammatory responses; it can progress to cirrhosis and eventually to hepatocellular carcinoma. Previously, we reported that neoagarooligosaccharides (NAOs), produced by the hydrolysis of agar by β-agarases, have hepatoprotective effects against acetaminophen overdose-induced acute liver injury. However, the effect of NAOs on chronic liver injury, including hepatic fibrosis, has not yet been elucidated. Therefore, we examined whether NAOs protect against fibrogenesis in vitro and in vivo. NAOs ameliorated PAI-1, α-SMA, CTGF and fibronectin protein expression and decreased mRNA levels of fibrogenic genes in TGF-β-treated LX-2 cells. Furthermore, downstream of TGF-β, the Smad signaling pathway was inhibited by NAOs in LX-2 cells. Treatment with NAOs diminished the severity of hepatic injury, as evidenced by reduction in serum alanine aminotransferase and aspartate aminotransferase levels, in carbon tetrachloride (CCl4)-induced liver fibrosis mouse models. Moreover, NAOs markedly blocked histopathological changes and collagen accumulation, as shown by H&E and Sirius red staining, respectively. Finally, NAOs antagonized the CCl4-induced upregulation of the protein and mRNA levels of fibrogenic genes in the liver. In conclusion, our findings suggest that NAOs may be a promising candidate for the prevention and treatment of chronic liver injury via inhibition of the TGF-β/Smad signaling pathway.


2013 ◽  
Vol 305 (8) ◽  
pp. C789-C799 ◽  
Author(s):  
Ariane Mallat ◽  
Sophie Lotersztajn

Liver fibrosis is the common scarring reaction associated with chronic liver injury that results from prolonged parenchymal cell injury and/or inflammation. The fibrogenic response is characterized by progressive accumulation of extracellular matrix components enriched in fibrillar collagens and a failure of matrix turnover. This process is driven by a heterogeneous population of hepatic myofibroblasts, which mainly derive from hepatic stellate cells and portal fibroblasts. Regression of fibrosis can be achieved by the successful control of chronic liver injury, owing to termination of the fibrogenic reaction following clearance of hepatic myofibroblasts and restoration of fibrolytic pathways. Understanding of the complex network underlying liver fibrogenesis has allowed the identification of a large number of antifibrotic targets, but no antifibrotic drug has as yet been approved. This review will highlight recent advances regarding the mechanisms that regulate liver fibrogenesis and fibrosis regression, with special focus on novel signaling pathways and the role of inflammatory cells. Translation of these findings to therapies will require continued efforts to develop multitarget therapeutic approaches that will improve the grim prognosis of liver cirrhosis.


2009 ◽  
Vol 50 ◽  
pp. S257
Author(s):  
S. De Minicis ◽  
C. Rychlicki ◽  
L. Trozzi ◽  
S. Saccomanno ◽  
C. Candelaresi ◽  
...  

2020 ◽  
Vol 4 (5) ◽  
pp. 906-917
Author(s):  
Lauren G. Poole ◽  
Asmita Pant ◽  
Holly M. Cline‐Fedewa ◽  
Kurt J. Williams ◽  
Bryan L. Copple ◽  
...  

2019 ◽  
Vol 20 (19) ◽  
pp. 4872 ◽  
Author(s):  
Zhao ◽  
Li ◽  
Feng ◽  
Zhang ◽  
Yuan ◽  
...  

A major fraction (MPT-W), eluted by deionized water, was extracted from mycelium polysaccharides of Termitomyces albuminosus (MPT), and its antioxidant, anti-fibrosis, and anti-inflammatory activities in CCl4-induced chronic liver injury mice, as well as preliminary characterizations, were evaluated. The results showed that MPT-W was a polysaccharide of α- and β-configurations containing xylose (Xyl), fucose (Fuc), mannose (Man), galactose (Gal), and glucose (Glc) with a molar ratio of 0.29:8.67:37.89:35.98:16.60 by gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared (FT-IR) spectroscopy. Its molecular weight (Mw), obtained by high-performance gel permeation chromatography (HPGPC), was 1.30 × 105 Da. The antioxidant assays in vitro showed that MPT-W displayed scavenging free-radical abilities. Based on the data of in vivo experiments, MPT-W could inhibit TGFβ1/Smad3 and NF-κB pathways; decrease the level and activity of cytochrome P4502E1 (CYP2E1), malonaldehyde (MDA) and serum enzyme; activate the HO-1/Nrf2 pathway; and increase antioxidant enzymes to protect the liver in CCl4-induced chronic liver injury mice. Therefore, MPT-W could be a potentially natural and functional resource contributing to antioxidant, hepatoprotective, and anti-inflammatory effects with potential health benefits.


2020 ◽  
Vol 40 (03) ◽  
pp. 307-320
Author(s):  
Michitaka Matsuda ◽  
Ekihiro Seki

AbstractChronic liver injury due to viral hepatitis, alcohol abuse, and metabolic disorders is a worldwide health concern. Insufficient treatment of chronic liver injury leads to fibrosis, causing liver dysfunction and carcinogenesis. Most cases of hepatocellular carcinoma (HCC) develop in the fibrotic liver. Pathological features of liver fibrosis include extracellular matrix (ECM) accumulation, mesenchymal cell activation, immune deregulation, and angiogenesis, all of which contribute to the precancerous environment, supporting tumor development. Among liver cells, hepatic stellate cells (HSCs) and macrophages play critical roles in fibrosis and HCC. These two cell types interplay and remodel the ECM and immune microenvironment in the fibrotic liver. Once HCC develops, HCC-derived factors influence HSCs and macrophages to switch to protumorigenic cell populations, cancer-associated fibroblasts and tumor-associated macrophages, respectively. This review aims to summarize currently available data on the roles of HSCs and macrophages in liver fibrosis and HCC, with a focus on their interaction.


2020 ◽  
Vol 12 (539) ◽  
pp. eaaw8523 ◽  
Author(s):  
JingHong Wan ◽  
Emmanuel Weiss ◽  
Sanae Ben Mkaddem ◽  
Morgane Mabire ◽  
Pierre-Marie Choinier ◽  
...  

Sustained hepatic and systemic inflammation, particularly originating from monocytes/macrophages, is a driving force for fibrosis progression to end-stage cirrhosis and underlies the development of multiorgan failure. Reprogramming monocyte/macrophage phenotype has emerged as a strategy to limit inflammation during chronic liver injury. Here, we report that LC3-associated phagocytosis (LAP), a noncanonical form of autophagy, protects against hepatic and systemic inflammation during chronic liver injury in rodents, with beneficial antifibrogenic effects. LAP is enhanced in blood and liver monocytes from patients with fibrosis and cirrhosis. Pharmacological inhibition of LAP components in human monocytes from patients with cirrhosis or genetic disruption of LAP in mice with chronic liver injury exacerbates both the inflammatory signature in isolated human monocytes and the hepatic inflammatory profile in mice, resulting in enhanced liver fibrosis. Mechanistically, patients with cirrhosis showed increased monocyte expression of Fc fragment of IgG receptor IIA (FcγRIIA) and enhanced engulfment of immunoglobulin G in LC3+ phagosomes that triggers an FcγRIIA/Src homology region 2 domain–containing phosphatase-1 (SHP-1) inhibitory immunoreceptor tyrosine-based activation motif (ITAMi) anti-inflammatory pathway. Mice overexpressing human FcγRIIA in myeloid cells show enhanced LAP in response to chronic liver injury and resistance to inflammation and liver fibrosis. Activation of LAP is lost in monocytes from patients with multiorgan failure and restored by specifically targeting ITAMi signaling with anti-FcγRIIA F(ab′)2 fragments, or with intravenous immunoglobulin (IVIg). These data suggest the existence of an ITAMi-mediated mechanism by which LAP might protect against inflammation. Sustaining LAP may open therapeutic perspectives for patients with chronic liver disease.


2020 ◽  
Vol 73 ◽  
pp. S527
Author(s):  
Adil Bhat ◽  
Sudrishti Chaudhary ◽  
Gaurav Yadav ◽  
Anupama Parasar ◽  
Chhagan Bihari ◽  
...  

2012 ◽  
Vol 303 (4) ◽  
pp. G498-G506 ◽  
Author(s):  
Jörn M. Schattenberg ◽  
Michael Nagel ◽  
Yong Ook Kim ◽  
Tobias Kohl ◽  
Marcus A. Wörns ◽  
...  

Chronic liver disease promotes hepatocellular injury involving apoptosis and triggers compensatory regeneration that leads to the activation of quiescent stellate cells in the liver. The deposition of extracellular matrix from activated myofibroblasts promotes hepatic fibrosis and the progression to cirrhosis with deleterious effects on liver physiology. The role of apoptosis signaling pathways in the development of fibrosis remains undefined. The aim of the current study was to determine the involvement of the caspase-8 homologue cellular FLICE-inhibitory protein (cFLIP) during the initiation and progression of fibrosis. Liver injury and fibrosis from carbon tetrachloride (CCl4) and thioacetamide (TAA) were examined in mice exhibiting a hepatocyte-specific deletion of cFLIP ( flip −/−). Acute liver injury from CCl4 and TAA were enhanced in flip −/− mice. This was accompanied by increased activation of caspase-3 and -9, pronounced phosphorylation of JNK, and decreased phosphorylation of Erk. Deletion of the cJun NH2-terminal kinase 2 (JNK2) in flip −/− mice protected from injury. Hepatic fibrosis was increased at baseline in 12-wk-old flip −/− mice, and progression of fibrosis from TAA was accelerated compared with the wild type. In conclusion, deletion of cFLIP in hepatocytes leads to increased fibrosis and accelerated fibrosis progression. This is accompanied by increased injury involving the activation of caspases and JNK2. Thus predisposition to liver injury involving increased hepatocellular apoptosis is a critical mediator of accelerated fibrogenesis, and prevention of liver injury will be a most important measure for patients with chronic liver disease.


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