• BMB Reports
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• v.53 no.8
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• pp.425-430
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• 2020

Tumor necrosis factor-inducible gene 6 protein (TSG-6) is a cytokine secreted by mesenchymal stem cells (MSCs) and regulates MSC stemness. We previously reported that TSG-6 changes primary human hepatic stellate cells (pHSCs) into stem-like cells by activating yes-associated protein-1 (YAP-1). However, the molecular mechanism behind the reprogramming action of TSG-6 in pHSCs remains unknown. Cluster of differentiation 44 (CD44) is a transmembrane protein that has multiple functions depending on the ligand it is binding, and it is involved in various signaling pathways, including the Wnt/β-catenin pathway. Given that β-catenin influences stemness and acts downstream of CD44, we hypothesized that TSG-6 interacts with the CD44 receptor and stimulates β-catenin to activate YAP-1 during TSG-6-mediated transdifferentiation of HSCs. Immunoprecipitation assays showed the interaction of TSG-6 with CD44, and immunofluorescence staining analyses revealed the colocalization of TSG-6 and CD44 at the plasma membrane of TSG-6-treated pHSCs. In addition, TSG-6 treatment upregulated the inactive form of phosphorylated glycogen synthase kinase (GSK)-3β, which is a negative regulator of β-catenin, and promoted nuclear accumulation of active/nonphosphorylated β-catenin, eventually leading to the activation of YAP-1. However, CD44 suppression in pHSCs following CD44 siRNA treatment blocked the activation of β-catenin and YAP-1, which inhibited the transition of TSG-6-treated HSCs into stem-like cells. Therefore, these findings demonstrate that TSG-6 interacts with CD44 and activates β-catenin and YAP-1 during the conversion of TSG-6-treated pHSCs into stem-like cells, suggesting that this novel pathway is an effective therapeutic target for controlling liver disease.

• The Korea Journal of Herbology
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• v.28 no.4
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• pp.49-55
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• 2013

Objectives : Mori Folium was popularly used as one of the traditional medicinal herbs. Although M. Folium has been cultivated for rearing silkworm historically, it's use has been expanded as natural therapeutic agent for the treatment of filariasis, diabetes and dropsy in East Asia. However, little has been known about the effect of M. Folium on liver fibrosis. Therefore, we would like to explore an anti-fibrogenic potential of M. Folium extract (MFE) using immortalized human hepatic stellate cell line, LX-2 cells. Methods : We examined the effects of MFE on the transforming growth factor ${\beta}1$ ($TGF{\beta}1$)-induced liver fibrosis in LX-2 cells. Cell viability, Smad binding element-driven luciferase activity, phosphorylations level of Smad 2/3, and expression level of $TGF{\beta}1$-dependent target genes were monitored in the MFE-treated LX-2 cells. Results : Up to 30 ${\mu}g/ml$ MFE treatment did not show any possible toxic effect in LX-2 cells. MFE inhibited $TGF{\beta}1$-inducible Smad binding element-driven luciferase activity and decreased the $TGF{\beta}1$-inducible phosphorylations of Smad 2 and Smad 3 in hepatic stellate cell in a dose dependent manner. Furthermore, increases of plasminogen activator inhibitor type 1, $TGF{\beta}1$ and matrix metalloproteinases 2 genes by $TGF{\beta}1$ were also attenuated by MFE treatment. Conclusions : These findings suggested that MFE would be used as a potential therapeutic agent for the treatment liver fibrosis, which might be mediated by the inhibition of $TGF{\beta}1$-inducible Smad 2/3 transactivation and target genes expression.

• Laboraroty Animal Research
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• v.34 no.4
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• pp.133-139
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• 2018

Nonalcoholic steatohepatitis (NASH) is becoming common chronic liver disease because of the increasing global prevalence of obesity and consequently Nonalcoholic fatty liver disease (NAFLD). However, the mechanism for progression of NAFLD to NASH and then cirrhosis is not completely understood, yet. The triggering of these hepatic diseases is thought from hepatocyte injury caused by over-accumulated lipid toxicity. Injured hepatocytes release damage-associated molecular patterns (DAMPs), which can stimulate the Kupffer cells (KCs), liver-resident macrophages, to release pro-inflammatory cytokines and chemokines, and recruit monocyte-derived macrophages (MDMs). The increased activation of KCs and recruitment of MDMs accelerate the progression of NAFLD to NASH and cirrhosis. Therefore, characterization for activation of hepatic macrophages, both KCs and MDMs, is a baseline to figure out the progression of hepatic diseases. The purpose of this review is to discuss the current understanding of mechanisms of NAFLD and NASH, mainly focusing on characterization and function of hepatic macrophages and suggests the regulators of hepatic macrophages as the therapeutic target in hepatic diseases.

• Biomolecules & Therapeutics
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• v.28 no.4
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• pp.320-327
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• 2020

In current study, we aimed to investigate whether the gentiopicroside (GPS) derived from Gentiana manshurica Kitagawa could block the progression of alcoholic hepatic steatosis to fibrosis induced by chronic ethanol intake. C57BL/6 mice were fed an ethanol-containing Lieber-DeCarli diet for 4 weeks. LX-2 human hepatic stellate cells were treated with GPS 1 h prior to transforming growth factor-β (TGF-β) stimulation, and murine hepatocyte AML12 cells were pretreated by GPS 1 h prior to ethanol treatment. GPS inhibited the expression of type I collagen (collagen I), α-smooth muscle actin (α-SMA) and tissue inhibitor of metal protease 1 in ethanol-fed mouse livers with mild fibrosis. In addition, the imbalanced lipid metabolism induced by chronic ethanol-feeding was ameliorated by GPS pretreatment, characterized by the modulation of lipid accumulation. Consistently, GPS inhibited the expression of collagen I and α-SMA in LX-2 cells stimulated by TGF-β. Inhibition of lipid synthesis and promotion of oxidation by GPS were also confirmed in ethanol-treated AML12 cells. GPS could prevent hepatic steatosis advancing to the inception of a mild fibrosis caused by chronic alcohol exposure, suggesting GPS might be a promising therapy for targeting the early stage of alcoholic liver disease.

• Journal of Life Science
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• v.27 no.2
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• pp.233-240
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• 2017

Previously, we have shown that Schisandra chinensis (Turcz.) Baill. (S. chinensis) has a protective effect against endoplasmic reticulum (ER) stress-induced hepatic steatosis. Gomisin A is a bioactive phytoestrogen derived from S. chinensis. In the present study, the in vitro and in vivo effects of gomisin A on ER stress and hepatic steatosis were investigated. We quantified the expression of markers of ER stress, including glucose regulated protein 78 (GRP78), C/EBP homolog protein (CHOP), and X-box-binding protein-1 (XBP-1), in HepG2 cells treated with tunicamycin or palmitate. Tunicamycin treatment in HepG2 cells induced the expression of markers of ER stress, including GRP78, CHOP, and XBP-1c. However, treatment with gomisin A reduced the expression of markers of ER stress. These inhibitory effects were also observed in palmitate-incubated HepG2 cells. The in vivo inhibitory effects of gomisin A were assessed in mice injected with tunicamycin or fed with a high fat diet (HFD). Gomisin A reduced the expression of markers of ER stress and decreased triglyceride levels in the livers of mice after tunicamycin injection or HFD feeding. Furthermore, gomisin A decreased the expression of inflammatory genes in palmitate-incubated HepG2 cells and the liver of HFD-fed obese mice. These results suggest that gomisin A inhibits ER stress and ameliorates hepatic steatosis induced by ER stress.

• Toxicological Research
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• v.21 no.2
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• pp.141-150
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• 2005

1,3-Dichloro-2-propanol (1,3-DCP) is known as chloride chemicals and causes severe hepatotoxic agent. The Ito cells and Kupffer's cells of the liver in the 5 old F344 Rats were exposed to 1,3-DCP gas chamber for 6 hours/ a day, 5 days/ a week, and 13 weeks, in the 0, 5, 20, 80 ppm, respectively. After then the body weights, liver weights, and relative liver weight to body weight were measured, and the hepatic tissues were prepared by the routine and Immunostain method, and observed by the LM, and EM. In the results, there were severe body weight decrease (p<0.05) in the 80 ppm of the male and female rats. The relative liver weights to the body weight were increased relate with exposed 1,3-DCP concentration (P<0.001). Inflammatory cells, infiltration was observed at the perivascular area in the 20 ppm exposed group, and bilirubin pigment infiltration, bile duct hyperplasia, inflammation hepatocytic necrosis, fibrosis were observed in the 80 ppm exposure group. In the 80 ppm exposure group, disarrangement of the endothelial cells, erythrocytes and hepatic cell fragment in the Disse space and numerous migration macrophages were observed in the necrotic area by EM observation. In the immunostained hepatic tissues positive stained ED1 cells were extremely increased (P<0.05) in central vein area, but ED2 was weakly positive immunostained in the 80 ppm exposed group. Immunostained desmin was observed in the Ito cell. It was no difference in the low and medium exposed group but it was typical increase in the necrotic area. In conclusion, These results suggest that NOAEL of 1,3-DCP may be 5 ppm in rats and the Immunostained of desmin, ED1 and ED2 positive cells activated in the inflammatory liver were related to the exposure volume and density. The increase of the Ito cells were related to the severe phagocytosis of the Kupffer's cells.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.4
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• pp.333-339
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• 2014

Exendin-4 (Ex-4), a glucagon-like peptide-1 receptor (GLP-1R) agonist, has been known to reverse hepatic steatosis in ob/ob mice. Although many studies have evaluated molecular targets of Ex-4, its mechanism of action on hepatic steatosis and fibrosis has not fully been determined. In the liver, glucose transporter 4 (GLUT4) is mainly expressed in hepatocytes, endothelial cells and hepatic stellate cells (HSCs). In the present study, the effects of Ex-4 on GLUT4 expression were determined in the liver of ob/ob mice. Ob/ob mice were treated with Ex-4 for 10 weeks. Serum metabolic parameters, hepatic triglyceride levels, and liver tissues were evaluated for hepatic steatosis. The weights of the whole body and liver in ob/ob mice were reduced by long-term Ex-4 treatment. Serum metabolic parameters, hepatic steatosis, and hepatic fibrosis in ob/ob mice were reduced by Ex-4. Particularly, Ex-4 improved hepatic steatosis by enhancing GLUT4 via GLP-1R activation in ob/ob mice. Ex-4 treatment also inhibited hepatic fibrosis by decreasing expression of connective tissue growth factor in HSCs of ob/ob mice. Our data suggest that GLP-1 agonists exert a protective effect on hepatic steatosis and fibrosis in obesity and type 2 diabetes.

• Journal of Yeungnam Medical Science
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• v.37 no.2
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• pp.136-140
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• 2020

Immunoglobulin G4 (IgG4)-associated autoimmune hepatitis (AIH) is a very rare subtype of autoimmune hepatitis and characterized by marked elevated serum IgG and hepatic infiltration of IgG4-expressing plasma cells. Pathologic confirmation of hepatic IgG4-expressing plasma cells is usually required for the final diagnosis of IgG4-associated AIH. Herein, we report the case of a 47-year-old female diagnosed with autoantibody-negative IgG4-associated AIH mimicking lymphoproliferative disorders.

• The Journal of Internal Korean Medicine
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• v.31 no.3
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• pp.415-424
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• 2010

Objectives : This study was performed to investigate the anti-fibrogenic effect of Angelica Gigantis Radix on cultured rat hepatic stellate cells. Materials and Methods : Hepatic stellate cells(HSC-T6) were treated with various concentrations of Angelica Gigantis Radix extract for both 24 and 48 hours. The extraction was done either with distilled water or 80% EtOH. After the treatment, cell viability, cell proliferation, procollagen production and the mRNA expression of the ASMA, TIMP1, TIMP2, procollagen Type 1a2, and Cytokine IL-6 production were measured by using MTT assay, BrdU assay, RT-PCR, procollagen Type I C-peptide EIA and IL-6 ELISA assay. Results : The cell viability treated with water extraction was significantly increased, but there were no significant changes treated with 80% EtOH extraction. The cell proliferation treated with water extraction decreased only in the 24 hours group, while there were significant decreases either in the 24 and 48 hours groups treated with 80% EtOH extraction. The mRNA expressions of the ASMA, TIMP2 and procollagen 1a2 decreased in a concentration-dependent manner in the 48 hours group. Procollagen production decreased in a concentration-dependent manner in both the 24 and 48 hours groups. Cytokine IL-6 production increased in a concentration-dependent manner in both the 24 and 48 hours groups. Conclusion : These results suggest that Angelica Gigantis Radix is beneficial in the treatment of cirrhotic patients as well as for patients with chronic hepatitis.

• The Journal of Korean Medicine
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• v.38 no.2
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• pp.53-60
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• 2017

Objectives: Beakdugu-tang (BDGT) consists of three medicinal herbs, and this prescription has long been used in treatment of various digestant problem in Korea. In this study, we designed to clarify mechanisms by which Korean traditional digestive medicine, BDGT, may exert anti-hepatic steatosis effects via improved insulin resistance cell model in human hepatocellular carcinoma (HepG2) and monocyte (THP-1). Materials and methods: The preparation of BDGT and constituents were extracted with 70% ethanol. HepG2 and THP-1 were treated with different concentrations of BDGT and constituents in the presence and absence of stimulants such as free fatty acids (FFAs) and oxidized low-density lipoprotein (ox-LDL), respectively. Results: The BDGT and its constituents inhibited the FFAs-stimulated lipid accumulation in HepG2 cells. Ethanol extracts of Amomum cardamomum (ACE) improved the ox-LDL induced insulin resistance in THP-1 cells. Also, treatment of monocytic cells with ACE increased anti-hepatic steatosis related gene levels including ABCA, ABCG and SR-B1. Conclusion: The results suggest that the ethanol extract of BDGT and its constituents potently inhibit the FFAs- and ox-LDL induced liver steatosis via improved insulin resistance.