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Hepatic fibrosis, as a common stage of multiple liver diseases, currently has no effective drug treatment. Emerging evidence shows that miRNAs participate in the progression of liver fibrosis. However, the potential role of miRNAs in hepatic fibrosis is not yet fully understood. Herein, we first confirmed that miR-345-5p expression was significantly decreased in activated hepatic stellate cells (HSCs) and fibrotic livers. Functional analysis showed that overexpression of miR-345-5p in human LX-2 cells suppressed the expression of profibrotic markers and cellular proliferation in vitro. Using a dual-luciferase assay, we demonstrated that miR-345-5p regulates HSC activation by targeting the 3'UTR of HIF-1α mRNA. In addition, overexpression of miR-345-5p in vivo alleviated murine liver fibrosis induced by carbon tetrachloride (CCl4) injection, high-fat diet (HFD) feeding and bile duct ligation (BDL). Furthermore, overexpression of miR-345-5p downregulated the expression of HIF-1α and fibrosis markers in livers from different fibrosis models. Collectively, we conclude that miR-345-5p mediates the activation of HSCs by targeting HIF-1α, which subsequently modulates TGFβ/Smad2/Smad3 signaling. Thus, miR-345-5p may become a novel therapeutic target for the treatment of liver fibrosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Although excessive mitochondrial fission is linked to cell activation, its significance in hepatic stellate cells (HSCs) activation and liver fibrosis is unknown. Here we show that excessive mitochondrial fission triggers HSCs activation and liver fibrosis degradation by the epigenetic regulation. We used a combination of in vitro and in vivo models including HSCs, clinical cases, and CCl 4 -induced liver fibrosis mice to investigate the regulation and function of mitochondrial fission in HSCs activation and liver fibrosis. Herein, we show that DNMT3A and Drp1 is up regulated in fibrosis livers and mice liver fibrosis tissues, while PGC-1α was decreased. Interestingly, down expression of DNMT3A substantially reduced Drp1 levels, collagen accumulation, and interstitial fibrosis, while significantly increased PGC-1α levels. Furthermore, silencing DNMT3A remarkably inhibits HSCs activation and mitochondrial fission both in vivo and in vitro. Mechanistically, co-immunoprecipitation analysis revealed that DNMT3A bound to pull down the protein of PGC-1α. These findings indicated that epigenetic control of mitochondrial fission enables HSCs activation in liver fibrosis via PGC-1α-Drp1 pathway, and provide new insight into the relationship between mitochondrial fission and liver fibrosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. and Mitochondria Research Society. All rights reserved.)

Simple Summary: The incidence of hepatocellular carcinoma (HCC) in patients with non-alcoholic fatty liver disease (NAFLD) has increased in recent years. Compared to HCC caused by other chronic liver diseases, NAFLD-related HCC is often detected later, because it more commonly arises before cirrhosis has occurred. Because of this late diagnosis, NAFLD-related HCC is often more advanced at time of diagnosis, resulting in fewer curative treatment options. Most research in the pathogenesis of HCC has focused on the disease processes in hepatocytes, the most abundant type of liver cells. However, other cell types, such as cells of the immune system and cells that regulate connective tissue formation, also play an important role in the development of NAFLD-related HCC, both by contributing to the development of HCC itself and by interfering with the immune system's ability to attack cancer cells. In this paper, we review the role of different cell types in the development of NAFLD-related HCC. Hepatocellular carcinoma (HCC) in the setting of non-alcoholic fatty liver disease (NAFLD)-related cirrhosis and even in the pre-cirrhotic state is increasing in incidence. NAFLD-related HCC has a poor clinical outcome as it is often advanced at diagnosis due to late diagnosis and systemic treatment response is poor due to reduced immune surveillance. Much of the focus of molecular research has been on the pathological changes in hepatocytes; however, immune cells, hepatic stellate cells, liver sinusoidal endothelial cells and the extracellular matrix may play important roles in the pathogenesis of NAFLD-related HCC as well. Here, we review the role of non-parenchymal cells in the liver in the pathogenesis of HCC in the context of NAFLD-NASH, with a particular focus on the innate and the adaptive immune system, fibrogenesis and angiogenesis. We review the key roles of macrophages, hepatic stellate cells (HSCs), T cells, natural killer (NK) cells, NKT cells and liver sinusoidal endothelial cells (LSECs) and the role of the extracellular matrix in hepatocarcinogenesis within the steatotic milieu. [ABSTRACT FROM AUTHOR]

Liver fibrosis is a common feature of progressive liver disease and is manifested as a dynamic series of alterations in both the biochemical and biophysical properties of the liver. Hepatic stellate cells (HSCs) reside within the perisinusoidal space of the liver sinusoid and are one of the main drivers of liver fibrosis, yet it remains unclear how changes to the sinusoidal microenvironment impact HSC phenotype in the context of liver fibrosis. Cellular microarrays were used to examine and deconstruct the impacts of bio-chemo-mechanical changes on activated HSCs in vitro. Extracellular matrix (ECM) composition and stiffness were found to act individually and in combination to regulate HSC fibrogenic phenotype and proliferation. Hyaluronic acid and collagen III promoted elevated collagen I expression while collagen IV mediated a decrease. Previously activated HSCs exhibited reduced lysyl oxidase (Lox) expression as array substrate stiffness increased, with less dependence on ECM composition. Collagens III and IV increased HSC proliferation, whereas hyaluronic acid had the opposite effect. Meta-analysis performed on these data revealed distinct phenotypic clusters (e.g. low fibrogenesis/high proliferation) as a direct function of their microenvironmental composition. Notably, soft microenvironments mimicking healthy tissue (1 kPa), promoted higher levels of intracellular collagen I and Lox expression in activated HSCs, compared to stiff microenvironments mimicking fibrotic tissue (25 kPa). Collectively, these data suggest potential HSC functional adaptations in response to specific bio-chemo-mechanical changes relevant towards the development of therapeutic interventions. These findings also underscore the importance of the microenvironment when interrogating HSC behavior in healthy, disease, and treatment settings. STATEMENT OF SIGNIFICANCE: In this work we utilized high-throughput cellular microarray technology to systematically interrogate the complex interactions between HSCs and their microenvironment in the context of liver fibrosis. We observed that HSC phenotype is regulated by ECM composition and stiffness, and that these phenotypes can be classified into distinct clusters based on their microenvironmental context. Moreover, the range of these phenotypic responses to microenvironmental stimuli is substantial and a direct consequence of the combinatorial pairing of ECM protein and stiffness signals. We also observed a novel role for microenvironmental context in affecting HSC responses to potential fibrosis therapeutics., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021. Published by Elsevier Ltd.)

Background: Hepatic stellate cells (HSCs) are reported to play significant roles in the development of liver fibrosis. Heme oxygenase-1 (HO-1) is a key rate-limiting enzyme, which could decrease collagen synthesis and liver damage. Nevertheless, it was yet elusive towards the function and mechanism of HO-1., Methods: An HO-1 inducer Hemin or an HO-1 inhibitor ZnPP-IX was used to treat the activated HSC-T6, respectively. MTT assay was adopted to detect cell proliferation. Immunocytochemical staining was employed to test the levels of alpha-smooth muscle actin ( α -SMA), peroxisome proliferator-activated receptor- γ (PPAR γ ), and nuclear factor-kappa B (NF-kappa B) levels in HSC-T6. HO-1, PPAR γ , and NF- κ B expression levels were measured by qRT-PCR and Western blotting. ELISA was then used to detect the levels of transforming growth factor- (TGF-) beta 1 (TGF- β 1), interleukin-6 (IL-6), serum hyaluronic acid (HA), and serum type III procollagen aminopeptide (PIIIP)., Results: HSC-T6 proliferation was inhibited in Hemin-treated HSCs. The levels of α -SMA, HA, and PIIIP and the production of ECM were lower in Hemin-treated HSCs, whereas those could be rescued by ZnPP-IX. NF- κ B activation was decreased, but PPAR γ expression was increased after HO-1 upregulation. Furthermore, the levels of TGF- β 1 and IL-6, which were downstream of activated NF- κ B in HSC-T6, were reduced. The PPAR-specific inhibitor GW9662 could block those mentioned effects., Conclusions: Our data demonstrated that HO-1 induction could inhibit HSC proliferation and activation by regulating PPAR γ expression and NF- κ B activation directly or indirectly, which makes it a promising therapeutic target for liver fibrosis., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2022 Hui Yang et al.)

Hepatic stellate cell activation, characterized by hyperproliferation and increased release of collagens, is a critical event during the initiation and development of hepatic fibrosis. The deregulated genes among different expression profiles based on online datasets were analyzed, attempting to identify novel potential biomarkers and treatment targets for hepatic fibrosis. The abnormal upregulation of mouse peptidylprolyl isomerase C (Ppic) within the CCl 4 -caused hepatic fibrosis model in mice was identified according to bioinformatics and experimental analyses. The knockdown of Ppic in the CCl 4 -caused liver fibrosis murine model significantly improved CCl 4 -caused liver damage, decreased the fibrotic area, reduced ECM deposition, and reduced the hydroxyproline levels. The knockdown of Ppic in TGF-β-stimulated mouse hepatic stellate cells inhibited cell proliferation and decreased ECM levels. Through direct targeting, miR-137-3p negatively regulated Ppic expression. Contrastingly to Ppic knockdown, miR-137-3p inhibition further promoted cell proliferation and boosted ECM levels; the effects of miR-137-3p inhibition could be partially reversed by Ppic knockdown. Altogether, mmu-miR-137-3p directly targets Ppic and forms a regulatory axis with Ppic, modulating CCl 4 -caused hepatic fibrosis in mice and TGF-β-caused mouse hepatic stellate cell activation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The interaction between various types of hepatic cells is related to liver fibrosis. Recent studies demonstrated that fine particulate matter (PM2.5) exposure is an important risk factor for the occurrence of liver fibrosis, but its molecular mechanism is still obscure. In this study, we aimed to investigate whether transforming growth factor- β1 (TGF- β1) secreted from PM2.5-treated hepatocytes (L-O2) are shuttled to hepatic stellate cells (HSCs) and to establish their effects on HSCs. We have observed that the conditioned medium from L-O2 cells stimulated with PM2.5 induced the activation of LX-2 cells, and at the same time, the same results were obtained when we co-cultured LX-2 in PM2.5-exposed L-O2 cells. In addition, analysis of L-O2 cells stimulated with PM2.5 revealed significant increases in TGF-β1 expression. Moreover, we found that the TGF-β1 receptor inhibitor, SB-525334, decreases the proliferation and migration of LX-2 cells in the co-culture system. In addition, the expression of α-smooth muscle actin and type I collagen in LX-2 cells induced by PM2.5-treated L-O2 cells were also blocked by pretreated with SB-525334. These observations imply that PM2.5 induces TGF- β1expression in hepatocytes, which leads to HSCs activation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Copyright of Tianjin Medical Journal is the property of Tianjin Medical Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Microcystin-leucine-arginine (MC-LR), produced by cyanobacteria, accumulates in the liver through blood circulation. We investigated the impact of MC-LR on liver fibrosis. Mice received a daily injection of MC-LR at various concentrations for 14 consecutive days aa and then mouse liver was obtained for histopathological and immunoblot analysis. Next, a human hepatic stellate cell line (LX-2) was treated with MC-LR at various concentrations followed by measurement of cell viability, cell cycle and relevant protein expression levels. Our data confirmed the induction of mouse liver fibrosis after exposure to MC-LR at 15 μg/kg and 30 μg/kg. Furthermore, we demonstrated that LX-2 cells could uptake MC-LR, resulting in cell proliferation and differentiation through impacting the Hedgehog signaling after the treatment of MC-LR at 50 nM. Our data supported that MC-LR could induce liver fibrosis by modulating the expression of the transcription factor Gli2 in the Hedgehog signaling in hepatic stellate cells., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Hepatic fibrosis is characterized by abnormal accumulation of extracellular matrix (ECM). Hepatic stellate cells (HSCs) are the primary cells that produce ECM in response to hepatic injury, and transforming growth factor-beta (TGF-β) has been regarded as the central stimulus responsible for HSC-mediated ECM production. In the present study, we attempted to identify a critical factor in HSC activation and the underlying mechanism. By analyzing online microarray expression profiles, we found that the expression of high-affinity cationic amino acid transporter 1 (CAT1) was upregulated in hepatic fibrosis models and activated HSCs. We isolated and identified mouse HSCs (MHSCs) and found that in these cells, CAT1 was most highly upregulated by TGF-β1 stimulation in both time- and dose-dependent manners. In vitro, CAT1 overexpression further enhanced, while CAT1 silencing inhibited, the effect of TGF-β1 in promoting MHSC activation. In vivo, CAT1 silencing significantly improved the hepatic fibrosis induced by both CCl4 and non-alcoholic fatty liver disease (NAFLD). In summary, CAT1 was significantly upregulated in TGF-β1-activated MHSCs and mice with hepatic fibrosis. CAT1 silencing inhibited TGF-β1-induced MHSC activation in vitro and fibrogenic changes in vivo. CAT1 is a promising target for hepatic fibrosis treatment that requites further investigation in human cells and clinical practice., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Liver fibrosis results from excessive accumulation of extracellular matrix (ECM) proteins that distort the hepatic architecture. Progression of liver fibrosis results in cirrhosis and liver failure, and often, liver transplantation is required. The decellularized liver tissue contains different components that mimic the natural hepatic environment. We hypothesized that a decellularized liver hydrogel can be used to replace the necrotic hepatocytes and damaged ECM. Therefore, our aim in this study is to develop a therapy for treating liver fibrosis. Mice livers were decellularized and processed to form a hepatic hydrogel. We evaluated the biocompatibility and bioactivity of the hydrogel. The ability of the hydrogel to enhance the migration of hepatocytes and endothelial cells was investigated. Human hepatic stellate cell line (LX-2) activated by transforming growth factor-β1 (TGF-β1) was used as in vitro model for fibrogenesis. Then, the hydrogel was injected into the liver parenchyma of mice after the induction of liver fibrosis using thioacetamide. The resulting hydrogel maintained a complex composition, which included glycosaminoglycans, collagen, elastin, and growth factors. Hepatocytes and endothelial cells were shown to migrate toward the hydrogel in vitro. Liver hydrogel improved TGF-β1-induced LX-2 cells activation via blocking the TGF-β1/Smad pathway. The matrix was delivered successfully in vivo and enhanced the reduction of fibrosis and recovery to a nearly normal structure. In conclusion, we have demonstrated that the liver hydrogel can be utilized as an injectable biomaterial for liver tissue engineering in order to reduce the degree of fibrosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Activated hepatic stellate cells (HSCs) play a central role in fibrillary collagen production, the primary cause of liver fibrosis. Although it is known that primary cultured HSCs are activated by plastic culture dish stiffness, HSC activation and quiescent-state-reversion mechanisms are still unclear. In this study, we used cultured normal rat HSCs on 3.2 kPa collagen normal liver stiffness equivalent gel, to determine whether high glucose or high succinate conditions induce HSC activation, and examined whether activated HSCs reverted to a quiescent state when suppressed by GPR91 antagonists or TGF-β1 receptor inhibitors. We measured the gene expression levels of α-SMA and type I collagen HSC activation markers using real-time PCR. Our data indicated that high glucose conditions induced HSC activation, and showed that under continuous high glucose exposure HSC activation progressed. A GPR91 antagonist, 2 d, and a TGF-β1 receptor inhibitor, SB525334, suppressed the Col1α mRNA expression level of these activated HSCs. Similarly, under extended high succinate exposure, 2 d and SB525334 reduced Col1α mRNA expression levels of activated HSCs. From the above, we determined that even though HSCs had already been activated by high glucose or succinate conditions which persisted after activation, the GPR91 antagonist and the TGF-β1 receptor inhibitor were able to reduce the production of type I collagen from activated HSCs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Objective: Hepatic stellate cells (HSC) activation and proliferation mediated the pathogenic development of hepatic fibrosis (HF). However, the underlying mechanisms remain poorly understood. In this study, we aimed to investigate the miR-29a-3p and its effects on PIK3R3 expression in HF pathogenesis., Methods: LX-2 cells treated with TGF-β1 was used as the in vitro HF model. The expression of microRNAs and proteins in LX-2 cells were detected by quantitative RT-PCR and western blotting. Then, miR-29a-3p expression in LX-2 cells were altered via transfection with specific mimics or inhibitors, followed by cell proliferation measured through CCK-8, Edu staining and colony formation. The dual luciferase reporter assay was done to assess binding of miR-29a-3p with PIK3R3 gene sequences. Moreover, PIK3R3 gene overexpression in LX-2 cell was realized through transfection with recombinant pcDNA3.0-PIK3R3 plasmids., Results: Successful establishment of cellular HF model was validated through the increased Col-I and a-SMA expression in TGF-β1-treated LX-2 cells shown by qRT-PCR and Western blot. In such model, miR-29a-3p expression in LX-2 cells showed the greatest decrease among four candidate microRNAs in response to TGF-β1 treatment. Also, miR-29a-3p directly binds with the 3' UTR region of the PIK3R3 gene to suppress its expression in LX-2 cells. Furthermore, PIK3R3 gene overexpression effectively abrogated the changes of LX-2 cell proliferation, AKT phosphorylation and Col-I and a-SMA expression caused by miR-29a-3p mimics., Conclusion: MiR-29a-3p regulates hepatic stellate cell proliferation and hepatic fibrosis pathogenesis by targeting PIK3R3 expression and modulating the PI-3K/AKT signaling., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Vitamin A is stored as retinyl esters (REs) in lipid droplets of hepatic stellate cells (HSCs). To date, two different pathways are known to facilitate the breakdown of REs: (i) Hydrolysis of REs by neutral lipases, and (ii) whole lipid droplet degradation in autolysosomes by acid hydrolysis. In this study, we evaluated the contribution of neutral and acid RE hydrolases to the breakdown of REs in human HSCs. (R)-Bromoenol lactone (R-BEL), inhibitor of adipose triglyceride lipase (ATGL) and patatin-like phospholipase domain-containing 3 (PNPLA3), the hormone-sensitive lipase (HSL) inhibitor 76-0079, as well as the serine-hydrolase inhibitor Orlistat reduced neutral RE hydrolase activity of LX-2 cell-lysates between 20 and 50%. Interestingly, in pulse-chase experiments, R-BEL, 76-0079, as well as Orlistat exerted little to no effect on cellular RE breakdown of LX-2 cells as well as primary human HSCs. In contrast, Lalistat2, a specific lysosomal acid lipase (LAL) inhibitor, virtually blunted acid in vitro RE hydrolase activity of LX-2 cells. Accordingly, HSCs isolated from LAL-deficient mice showed RE accumulation and were virtually devoid of acidic RE hydrolase activity. In pulse-chase experiments however, LAL-deficient HSCs, similar to LX-2 cells and primary human HSCs, were not defective in degrading REs. In summary, results demonstrate that ATGL, PNPLA3, and HSL contribute to neutral RE hydrolysis of human HSCs. LAL is the major acid RE hydrolase in HSCs. Yet, LAL is not limiting for RE degradation under serum-starvation. Together, results suggest that RE breakdown of HSCs is facilitated by (a) so far unknown, non-Orlistat inhibitable RE-hydrolase(s)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Arsenic trioxide (ATO) can bind directly to the human promyelocytic leukemia (PML) protein, leading to modification of PML by SUMOs. UBC9 is the only known E2-conjugating enzyme involved in SUMOylation. PML degradation via RNF4, an E3 ubiquitin ligases family member. PML is key organizer of nuclear bodies (NBs) that regulate many biological processes such as senescence, and DNA damage. ATO can activate the TGFβ/Smad signaling pathway, causing liver fibrosis. However, the roles of PML Sumoylation in ATO-induced liver fibrosis remain unclear., Objective: This study aimed to investigate the role of PML Sumoylation in the ATO-induced HSCs activation and to improve the mechanism of ATO-induced liver fibrosis., Methods: Hepatic stellate cells (HSCs) were treated with 2 μmol/L ATO. Cell viability was detected by CCK-8 analysis. Immunoblot analysis and real-time quantitative PCR were used to detect the expression of IL-1β, TNF-α, TGF-β1, p-Smad2/3, α-SMA, Collagen I and PML SUMOylation after silencing PML, UBC9, and RNF4, respectively. The formation of PML-NBs was observed by immunofluorescence staining., Results: 2 and 5 μmol/L ATO intervention increased HSCs cell viability. ATO was able to significantly trigger PML SUMOylation and the formation of PML-NBs. Inhibition of SUMOylated PML by silencing UBC9, subsequently preventing the downregulation of HSCs activation indicators induced by ATO (P < 0.05). Conversely, enhancing SUMOylated PML accumulation by silencing RNF4, activating TGFβ/Smad signaling pathway, eventually promoting the induction of liver fibrosis., Conclusion: These results indicated that PML SUMOylation plays a critical role in the development of liver fibrosis induced by ATO., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest. The authors are solely responsible for the writing and content of the paper. The author's affiliation is as shown on the cover page., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Vitamin A (retinol) is important for normal growth, vision and reproduction. It has a role in the immune response and the development of metabolic syndrome. Most of the retinol present in the body is stored as retinyl esters within lipid droplets in hepatic stellate cells (HSCs). In case of liver damage, HSCs release large amounts of stored retinol, which is partially converted to retinoic acid (RA). This surge of RA can mediate the immune response and enhance the regeneration of the liver. If the damage persists activated HSCs change into myofibroblast-like cells producing extracellular matrix, which increases the chance of tumorigenesis to occur. RA has been shown to decrease proliferation and metastasis of hepatocellular carcinoma. The levels of RA and RA signaling are influenced by the possibility to esterify retinol towards retinyl esters. This suggests a complex regulation between different retinoids, with an important regulatory role for HSCs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Hepatic stellate cells (HSCs) play vital roles in tumorigenesis and progression of hepatocellular carcinoma (HCC). However, there remains a lack of high-throughput studies on gene expression alterations in HCC cells in response to direct interactions with HSCs. In this study, we established a direct co-culture model of HSCs and HCC cells. We found that the expression of a set of miRNAs, most notably miR-1246, was triggered by HSCs. RORα was confirmed as the target gene of miR-1246. Either overexpression of miR-1246 or knockdown of RORα enhanced the proliferation, invasiveness, and metastatic capability of HCC both in vitro and in vivo, through Wnt/β-catenin pathway activation and promotion of epithelial-mesenchymal transition (EMT). Moreover, upregulation of miR-1246 and repression of RORα were prominent features of aggressive clinical HCC. The miR-1246-RORα-Wnt/β-catenin axis is a novel pathway through which HSCs accelerate HCC progression., Competing Interests: Declaration of competing interest This paper has not been submitted elsewhere for consideration of publication. The authors certify that they have participated sufficiently in the work to take public responsibility for the appropriateness of the experimental design and method, and the collection, analysis, and interpretation of the data. All authors have reviewed the final version of the manuscript and approved to submit it to your journal. There is no conflict of interest of any authors in relation to the submission., (Copyright © 2020 Elsevier B.V. All rights reserved.)

This paper was aimed to observe the interventional effect of Sedum sarmentosum total flavanones on hepatic fibrosis and its possible mechanism through the subcutaneous injection of CCl&#95;4 in rats. Sixty male SD rats were randomly divided into normal control group, model group, low-dose, medium-dose, high-dose S. sarmentosum total flavanones groups(100, 200, 400 mg·kg~(-1)) and silymarin group(200 mg·kg~(-1)). The model of liver fibrosis was established by subcutaneous injection of rats with 40% CCl&#95;4. After the modeling, the drug groups were intragastrically administered with corresponding drugs once a day for consecutively five weeks, while the normal group and the model group were given 0.9% sodium chloride solution during the same period. After the experiment, the general conditions of rats and the pathological changes of liver tissues were observed, and the contents of serum ALT, AST, HA and LN were measured. Besides, the expressions of the protein and relevant mRNA of Smad2/3, Smad4 and α-SMA in rats were detected. Compared with model group, S. sarmentosum total flavanones could significantly increase the rats' body weight, inhibit the increase of liver and spleen index in rats of liver fibrosis, reduce the levels of ALT, AST, HA and LN, and alleviate pathological changes. Meanwhile, compared with the model group, the protein expressions of Smad2/3, Smad4 and α-SMA as well as relevant mRNA expressions in S. sarmentosum total flavanones group were obviously decreased, while Smad7 expression was markedly increased. As a result, S. sarmentosum total flavanones could significantly alleviate CCl&#95;4-induced liver fibrosis, and its anti-hepatic fibrosis mechanism may be related to intervention with Smads pathway, so as to inhibit the activation of HSC.

Liver fibrosis is a common pathological consequence of liver injury, which increases liver failure-related morbidity and mortality. Hence, anti-fibrotic treatment is urgently needed. Oxidative stress plays a pivotal role in the progression of liver fibrosis. Thus, targeting ROS may be an effective strategy for liver fibrosis treatment. In this study, we investigated four benzoquinones derivatives, including 5-isopropyl-2-methyl-1,4-benzoquinone (TQ), 2-tert-butyl-1,4-benzoquinone ( t Bu-Q) 2,5-dimethyl-p-benzoquinone (Dime-Q) and p-benzoquinone (Ph-Q), as well as the evaluation of their antioxidant activity and anti-fibrotic effects on activated hepatic stellate cells and TAA-induced mice. Electrochemical analysis showed that all compounds possessed antioxidant property. The result was first confirmed by in vitro experiments, which revealed potential anti-fibrotic activity of all four compounds at the cellular level. Benzoquinone derivatives act as ROS-scavenging molecules, which modulated the TLR4-CD14 signaling pathway to inhibit the expression of procaspase-1 and IL-1β in cells, induced apoptosis via a mitochondrial pathway by upregulating the ratio of Bax/Bcl-2 and by activating caspase-3, as well as inhibited the expression of the anti-apoptotic proteins FLIP and XIAP in activated LX-2 cells. In addition, a TAA (Thioacetamide)-induced mouse model was used to further validate the results. Treatment with benzoquinone derivatives significantly decreased the levels of liver injury markers and lipid peroxidation caused by excessive ROS, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), and malondialdehyde (MDA). Moreover, treatment with benzoquinone derivatives significantly inhibited extracellular matrix (ECM) deposition and downregulated the mRNA and protein expression of liver fibrosis markers, such as collagen I, alpha-smooth muscle actin (α-SMA), and TIMP-1. In summary, these results indicate that benzoquinone derivatives may act as potential therapeutic drugs against liver fibrosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The core of hepatic fibrosis is the activation of hepatic stellate cells. Through the lipopolysaccharide/TLR4/MyD88/NF-KB signal transduction pathway, the inflammatory response in the liver is directly enhanced, and then returns to promote the activation of hepatic stellate cells. And TLR4/MyD88/NF-κB signaling pathway can directly regulate the activation of NLRP3 inflammasome and is an important pathway for activating hepatic stellate cells. TLR4/MyD88/NF-κB/NLRP3 inflammasome pathway is regulated by upstream microRNAs. These miR-NAs can significantly regulate the inflammatory response of the liver and the activation behavior of hepatic stellate cells, affecting the formation of liver fibrosis. Previous studies have found that the active ingredient of Guangxi specialty ethnic medicine, plumbagin, has a definite anti liver fibrosis effect, but its mechanism of action is not clear. This paper provides a review of the research progress on the above issues, and further research ideas have been derived from this, stating that" the anti liver fibrosis effect of plumbagin is achieved by regulating miRNA/TLR4/MyD88/NF-κB inflammatory pathway and activating downstream NLRP3 inflammasome". [ABSTRACT FROM AUTHOR]

Copyright of Tianjin Medical Journal is the property of Tianjin Medical Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: Carvedilol is a nonselective beta-blocker used to reduce portal hypertension. This study investigated the effects and potential mechanisms of carvedilol in angiotensin II- (Ang II-) induced hepatic stellate cell (HSC) proliferation and contraction., Methods: The effect of carvedilol on HSC proliferation was measured by Cell Counting Kit-8 (CCK-8). Cell cycle progression and apoptosis in HSCs were determined by flow cytometry. A collagen gel assay was used to confirm HSC contraction. The extent of liver fibrosis in mice was evaluated by hematoxylin-eosin (H&E) and Sirius Red staining. Western blot analyses were performed to detect the expression of collagen I, collagen III, α -smooth muscle actin ( α -SMA), Ang II type I receptor (AT1R), RhoA, Rho-kinase 2 (ROCK2), and others., Results: The results showed that carvedilol inhibited HSC proliferation and arrested the cell cycle at the G0/G1 phase in a dose-dependent manner. Carvedilol also modulated Bcl-2 family proteins and increased apoptosis in Ang II-treated HSCs. Furthermore, carvedilol inhibited HSC contraction induced by Ang II, an effect that was associated with AT1R-mediated RhoA/ROCK2 pathway interference. In addition, carvedilol reduced α -SMA expression and collagen deposition and attenuated liver fibrosis in carbon tetrachloride (CCl 4 )-treated mice. The in vivo data further confirmed that carvedilol inhibited the expression of angiotensin-converting enzyme (ACE), AT1R, RhoA, and ROCK2., Conclusions: The results indicated that carvedilol dose-dependently inhibited Ang II-induced HSC proliferation by impeding cell cycle progression, thus alleviating hepatic fibrosis. Furthermore, carvedilol could inhibit Ang II-induced HSC contraction by interfering with the AT1R-mediated RhoA/ROCK2 pathway., Competing Interests: The authors declare that there are no conflicts of interest regarding the publication of this paper., (Copyright © 2019 Ying Wu et al.)

The contractile force of hepatic stellate cells plays a very important role in liver damage, hepatitis and fibrosis. In this paper, a method based on polydimethylsiloxane (PDMS) thin micropillar arrays is proposed to measure the contractile force of human hepatic stellate cell line LX-2, which enables dynamic measurement of the subcellular distribution of force magnitude and direction. First, thin micropillar arrays on glass bottom dish were fabricated using two-step casting process in order to meet the working distance requirement of 100× objective lens. After hydrophilic treatment and protein imprint, cells were seeded on the micropillar arrays. LX-2 cells, which were quiesced by growth in serum-free medium, were activated by adding fetal bovine serum (FBS). The deflections of the micropillars were achieved by image processing technique, and then the contractile force of cells exerted on the micropillars was calculated according to mechanical simulation results, and was analyzed under both quiescent and activated conditions. The experimental results show that the average traction force of quiescent cells is about 20 nN, while the contractile force of activated cells increased to 110 nN upon adding FBS. This method can quantify the contractile force of LX-2 cell on subcellular scale in both quiescent and activated states, which may benefit pathology study and drug screen for chronic liver diseases resulted from liver fibrosis.

Hepatic sinusoidal endothelial cell is a highly differentiated cell in hepatic sinusoid, and plays an important role in the occurrence and development of hepatic fibrosis. The dysfunction of hepatic sinusoidal endothelial cells is considered to be the key cause of a variety of liver diseases. At present, the researches on hepatic fibrosis at home and abroad are mainly focused on inhibiting the activation of hepatic stellate cells and accelerating the hydrolysis of extracellular matrix. However, there are few studies on the important role of the structure and function of hepatic sinusoidal endothelial cells in hepatic fibrosis. This paper reviews the research progress on the effect of hepatic sinusoidal endothelial cells on hepatic fibrosis and its regulatory mechanism in recent years. This paper summarizes the results of the research on the structural characteristics of hepatic sinusoidal endothelial cells, secretion of fibrosis-related cytokines and regulation of hepatic stellate cells activation in the development of hepatic fibrosis. [ABSTRACT FROM AUTHOR]

Hepatitis B virus (HBV) infection is a liver disorder that can result in cirrhosis, liver failure and hepatocellular carcinoma. HBV infection remains a major global health problem, as it affects more 350 million people chronically and kills roughly 600,000 people annually. Drugs currently used against HBV include IFN-α that decreases viremia, inflammation and the growth of liver fibrosis, and adefovir that decreases the viral load. Each of these drugs can have severe side-effects. In the present paper, we consider the treatment of chronic HBV by a combination of IFN-α and adefovir, and raise the following question: What should be the optimal ratio between IFN-α and adefovir in order to achieve the best 'efficacy' under constraints on the total amount of the drugs; here the efficacy is measured by the reduction of the levels of inflammation and of fibrosis? We develop a mathematical model of HBV pathogenesis by a system of partial differential equations (PDEs) and use the model to simulate a 'synergy map' which addresses the above question.

Background: Numerous documents have indicated a critical role of autophagy in alcoholic liver fibrosis (ALF), but few papers have reported its function in hepatic stellate cells (HSCs) activation. The current study aimed to investigate the regulation effect of autophagy in HSCs activation, in further to explore the underlying mechanism involved., Methods: HSC-T6 cells were treated with ethanol, 3-MA (autophagy inhibitor) or rapamycin (autophagy inducer), and cells were also transfected with si-Nrf2 or si-Keap1. Moreover, ALF animal model was established and Nrf-2 (-/-) , Keap1 (-/-) mice were purchased. The level of autophagy, the expression of α-SMA and CoL1A1, and Nrf2 antioxidant response were evaluated in stellate cells and livers., Results: Ethanol treatment in cultured cells increased autophagy, oxidative stress level and promoted HSCs activation. Inhibition of autophagy reversed alcohol-induced HSCs activation and suppressed HSCs oxidative stress. Nrf2-Keap1-ARE pathway was involved in HSCs activation and oxidative stress regulated by autophagy. In addition, through in vivo study, we found that inhibition of autophagy could alleviate alcoholic fatty liver injury in ALF model mice and Nrf2 signaling was involved in autophagy regulated HSCs activation., Conclusion: These data implicated mechanisms underlying autophagy in regulating the fibrogenic response in HSCs activation., (Copyright © 2018 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.)

Cholestatic liver injury results from impaired bile flow or metabolism and promotes hepatic inflammation and fibrogenesis. Toxic bile acids that accumulate in cholestasis induce apoptosis and contribute to early cholestatic liver injury, which is amplified by accompanying inflammation. The aim of the current study was to evaluate the role of the antiapoptotic caspase 8-homolog cellular FLICE-inhibitory (cFLIP) protein during acute cholestatic liver injury. Transgenic mice exhibiting hepatocyte-specific deletion of cFLIP (cFLIP -/- ) were used for in vivo and in vitro analysis of cholestatic liver injury using bile duct ligation (BDL) and the addition of bile acids ex vivo. Loss of cFLIP in hepatocytes promoted acute cholestatic liver injury early after BDL, which was characterized by a rapid release of proinflammatory and chemotactic cytokines (TNF, IL-6, IL-1β, CCL2, CXCL1, and CXCL2), an increased presence of CD68 + macrophages and an influx of neutrophils in the liver, and resulting apoptotic and necrotic hepatocyte cell death. Mechanistically, liver injury in cFLIP -/- mice was aggravated by reactive oxygen species, and sustained activation of the JNK signaling pathway. In parallel, cytoprotective NF-κB p65, A20, and the MAPK p38 were inhibited. Increased injury in cFLIP -/- mice was accompanied by activation of hepatic stellate cells and profibrogenic regulators. The antagonistic caspase 8-homolog cFLIP is a critical regulator of acute, cholestatic liver injury. NEW & NOTEWORTHY The current paper explores the role of a classical modulator of hepatocellular apoptosis in early, cholestatic liver injury. These include activation of NF-κB and MAPK signaling, production of inflammatory cytokines, and recruitment of neutrophils in response to cholestasis. Because these signaling pathways are currently exploited in clinical trials for the treatment of nonalcoholic steatohepatitis and cirrhosis, the current data will help in the development of novel pharmacological options in these indications.

With the arrival of atomic force microscopy (AFM) about thirty years ago, this new imaging tool opened up a new area for the exploration of biological samples, ranging from the tissue and cellular level down to the supramolecular scale. Commercial instruments of this new imaging technique began to appear in the five years following its discovery in 1986 by Binnig, Quate & Gerber. From that point onwards the AFM has attracted many liver biologists, and the number of publications describing structure-function relationships on the diverse set of liver cells has grown steadily ever since. It is therefore timely to reflect on the achievements of AFM in disclosing the cellular architecture of hepatocytes, liver sinusoidal endothelial cells, Kupffer cells, stellate cells and liver-associated natural killer cells. In this thematic paper, we present new data and provide an in-depth overview of the current AFM literature on liver cell biology. We furthermore include a future outlook on how this scanning probe imaging tool and its latest developments can contribute to clarify various structural and functional aspects of cells in liver health and disease., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Schistosomiasis is characterized by egg deposition, granulomatous inflammatory reaction and then subsequent hepatic fibrosis formation. Activated HSCs are regarded as the main effector cells in the progression of liver fibrosis and induction of senescence in hepatic stellate cells (HSCs) is vital to the reversion of hepatic fibrosis. Our previous work has showed that S. japonicum egg antigen p40 (Sjp40) could promote HSCs senescence via a STAT3/p53/p21 mechanism. In this paper, the major aim was to explore whether there are other signaling pathways in the process of Sjp40-induced HSCs aging and the underlying effect of SKP2/P27 signal pathway in this procedure. We observed the Sjp40-induced decrease of α-SMA and the senescence of LX-2 cells, and Sjp40 could upregulate P27 and downregulate the protein level of SKP2. The senescence induced by Sjp40 might be reversed in LX-2 cells that treated with P27-specific siRNA or with SKP2-special over-expression plasmid. In addition, we also demonstrated that the decreased expression of P-Rb and α-SMA induced by Sjp40 were partly restored by SKP2-overexpression. These data suggest that Sjp40 might inhibit HSCs activation by promoting cellular senescence via SKP2/P27 signaling pathway, which put forward novel mechanism in the treatment of liver fibrosis.

Nanomaterials are widely used in biomedical applications such as drug delivery, bioimaging, and photothermal therapy. For example, graphene oxide (GO) nanomaterials are among the most popular drug delivery vehicles in treating liver diseases due to their tunable chemical/physical properties, and biocompatibility. However, it has been reported that nanomaterials tend to accumulate in livers. The biophysical impact of the accumulation in liver cells remains unclear, and it may cause the liver fibrosis in the long run. The activation of hepatic stellate cells (HSCs) is one of the key initial steps of liver fibrosis. In this paper, we explored the geometric effect (nanosheets vs. quantum dots) of GO nanomaterials on human HSCs, in terms of cell viability, fibrotic degree, mobility and regulation pathways. Our study showed that GO nanosheets could significantly reduce HSCs cell viability and mobility. The protein expression levels of TGFβRⅡ/Smad2/Smad3 decreased, corresponding to a trend of attenuating fibrotic degree. However, the expression level of α-SMA, a maker protein of fibrosis, increased and contradicted with the projection. Further investigation on mitochondria showed that GO nanosheets disrupted mitochondria membrane and membrane potentials. We found that while modulating fibrotic effect through the TGF-β pathway, GO nanosheets induced oxidative stress and activated HSCs through reactive oxygen species(ROS)pathway. This was confirmed by the decreased expression level of α-SMA after co-incubation of GO nanosheets and n-acetyl cysteine (NAC) with HSCs. GO quantum dots decreased α-SMA expression level at 100 mg/l, along with decrease in GAPDH expression level and constant expression level of β-actin. The correlation between GAPDH and α-SMA remains to be explored. Our study suggested that the biophysical impacts of GO nanomaterials on HSCs are geometry-dependent. Both GO nanosheets and quantum dots can be adapted for attenuating liver fibrosis with further investigation on mechanisms. • The effect of graphene oxide nanomaterials on hepatic stellate cells is geometry-dependent. • Graphene oxide nanosheets triggered TGF-β pathway with disruption of cytoskeleton. • Graphene oxide nanosheets increased oxidative stress by physical interaction with mitochondria. • Graphene oxide nanosheets triggered two counteracting regulation pathways that offset anti-fibrotic effect. • Graphene oxide quantum dots demonstrated anti-fibrotic effect and distinctly decreased GAPDH expression level. [ABSTRACT FROM AUTHOR]

Background: The adenosine-adenosine receptor pathway plays important roles in the immune system and inflammation. Four adenosine receptors (i.e., A1R, A2AR, A2BR, and A3R) have been identified. However, the roles of these receptors were different in the disease progress and even play opposite roles in the same disease. This study aims to investigate the roles of A1R/A2AR/A2BR/A3R activation in liver fibrosis. Methods: Intraperitoneal injection of CCl4 into C57BL/6 mice was used to induce liver fibrosis in the models. Adenosine receptor agonists CCPA, CGS21680, BAY 60-6583, and namodenoson were used for A1R/A2AR/A2BR/A3R activation, respectively. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were used to evaluate the liver function. Hematoxylin and eosin (H&E) staining was used to investigate the pathological damage. Masson staining and Sirius Red staining were performed to evaluate the degree of collagen deposition. CCK8 and scratch assays were used to investigate the proliferation and migration ability of hepatic stellate cells (HSCs). Results: By using liver fibrosis mouse models, we observed that the A1R and A2AR agonists aggravated liver fibrosis, characterized by increasing ALT and AST levels, more serious liver pathological damage, and collagen deposition. However, the A2BR and A3R agonists alleviated liver fibrosis. Moreover, the A1R and A2AR agonist treatment promotes the proliferation and migration of HSC line LX2, while A2BR and A3R agonist treatment inhibited LX2 proliferation and migration. Consistently, A1R and A2AR agonist treatment elevated the expression of a-SMA and Col1a1 in LX2, whereas A2BR and A3R agonist treatment inhibited the expression of a-SMA and Col1a1 in LX2 cells. Additionally, 5'-N-ethylcarboxamidoadenosine (NECA), a metabolically stable adenosine analog, alleviated liver fibrosis and inhibited LX2 cell activity, proliferation, and migration. Conclusion: This study demonstrated the different roles of A1R/A2AR/A2BR/A3R during liver fibrosis development via regulating the HSC activity and proliferation. [ABSTRACT FROM AUTHOR]

Liver fibrosis is a serious global health issue for which effective treatment remains elusive. Chemical-induced hepatocyte-like cells (ciHeps) have emerged as an appealing source for cell transplantation therapy, although they present several challenges such as the risk of lung thromboembolism or hemorrhage. Apoptotic vesicles (apoVs), small membrane vesicles generated during the apoptosis process, have gained attention for their role in regulating various physiological and pathological processes. In this study, we generated ciHep-derived apoVs (ciHep-apoVs) and investigated their therapeutic potential in alleviating liver fibrosis. Our findings revealed that ciHep-apoVs induced the transformation of macrophages into an anti-inflammatory phenotype, effectively suppressed the activity of activated hepatic stellate cells (aHSCs), and enhanced the survival of hepatocytes. When intravenously administered to mice with liver fibrosis, ciHep-apoVs were primarily engulfed by macrophages and myofibroblasts, leading to a reduction in liver inflammation and fibrosis. Proteomic and miRNA analyses showed that ciHep-apoVs were enriched in various functional molecules that modulate crucial cellular processes, including metabolism, signaling transduction, and ECM-receptor interactions. ciHep-apoVs effectively suppressed aHSCs activity through the synergistic inhibition of glycolysis, the PI3K/AKT/mTOR pathway, and epithelial-to-mesenchymal transition (EMT) cascades. These findings highlight the potential of ciHep-apoVs as multifunctional nanotherapeutics for liver fibrosis and provide insights into the treatment of other liver diseases and fibrosis in other organs. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the effect of exosomes derived from gastric cancer cells on the phenotypic transformation of hepatic stellate cells (HSCs) and the effect of HSC activation on the malignant behavior of gastric cancer cells, including its molecular mechanism. Methods: Exosomes derived from the human gastric adenocarcinoma cell line AGS were extracted and purified by polymer precipitation and ultrafiltration, respectively. The exosomes' morphologic characteristics were observed using transmission electron microscopy, particle size was determined through nanoparticle-tracking analysis, and marker proteins were detected using western blotting. Exosome uptake by LX-2 HSCs was observed through fluorescence-based tracing. Reverse transcription quantitative PCR (RT-qPCR) was used to detect the messenger RNA (mRNA) expression of alpha-smooth muscle actin (α-SMA) and fibroblast activation protein (FAP). Using functional assays, the effects of LX-2 HSC activation on the biological behavior of malignant gastric cancer cells were evaluated. The effects of LX-2 HSC activation on the protein expression of epithelial–mesenchymal transition (EMT)-related genes and β-catenin were evaluated via western blotting. Results: The extracted particles conformed to the definitions of exosomes and were thus considered gastric cancer cell-derived exosomes. Fluorescence-based tracing successfully demonstrated that exosomes were enriched in LX-2 HSCs. RT-qPCR revealed that the mRNA expression of the cancer-associated fibroblast markers α-SMA and FAP was significantly increased. LX-2 HSC activation considerably enhanced gastric cancer cell proliferation, invasion, and migration. Western blotting showed that the expression of the EMT-related epithelial marker E-cadherin was significantly downregulated, whereas the expression of interstitial markers (N-cadherin and vimentin) and β-catenin was remarkably upregulated in gastric cancer cells. Conclusion: Exosomes derived from gastric cancer cells promoted phenotypic transformation of HSCs and activated HSCs to become tumor-associated fibroblasts. Gastric cancer cell-derived cells significantly enhanced gastric cancer cell proliferation, invasion, and migration after HSC activation, which may promote EMT of gastric cancer cells through the Wnt/β-catenin pathway. [ABSTRACT FROM AUTHOR]

Accumulating data reveal that garlic has beneficial effects against chronic liver disease. We previously reported that diallyl trisulfide (DATS), the primary organosulfur compound in garlic, reduced fibrosis and attenuated oxidative stress in rat fibrotic liver. The present study was aimed at elucidating the underlying mechanisms. The primary rat hepatic stellate cells (HSCs) were cultured and stimulated with hydrogen peroxide (H 2 O 2 ) for inducing HSC activation under oxidative stress. We examined the effects of DATS on the profibrogenic properties and oxidative stress in H 2 O 2 -treated HSCs. The results showed that DATS suppressed and reduced fibrotic marker expression in HSCs. DATS arrested cell cycle at G2/M checkpoint associated with downregulating cyclin B1 and cyclin-dependent kinase 1, induced caspase-dependent apoptosis, and reduced migration in HSCs. Moreover, intracellular levels of reactive oxygen species and lipid peroxide were decreased by DATS, but intracellular levels of glutathione were increased in HSCs. Furthermore, DATS significantly elevated hydrogen sulfide (H 2 S) levels within HSCs, but iodoacetamide (IAM) reduced H 2 S levels and significantly abrogated DATS production of H 2 S within HSCs. IAM also abolished all the inhibitory effects of DATS on the profibrogenic properties and oxidative stress in HSCs. Altogether, we demonstrated an H 2 S-associated mechanism underlying DATS inhibition of profibrogenic properties and alleviation of oxidative stress in HSCs. Modulation of H 2 S production may represent a therapeutic remedy for liver fibrosis., Competing Interests: The authors declare that there is no conflict of interests regarding the publication of this paper.

Background: Liver fibrosis was viewed as a reversible process. The activation of hepatic stellate cells (HSCs) is a key event in the process of liver fibrosis. The induction of senescence of HSCs would accelerate the clearance of the activated HSCs. Previously, we demonstrated that soluble egg antigens (SEA) of Schistosoma japonicum promoted the senescence of HSCs via STAT3/P53/P21 pathway. In this paper, our study was aimed to explore whether there are other signaling pathways in the process of SEA-induced HSCs aging and the underlying effect of SKP2/P27 signal on senescent HSCs., Methodology/principal Findings: Human hepatic stellate cell line, LX-2 cells, were cultured and stimulated with SEA. Western blot and cellular immunofluorescence analysis were performed to determine the expression of senescence-associated protein, such as P27, SKP2 and FoxO3a. Besides, RNA interfering was applied to knockdown the expression of related protein. The senescence of HSCs was determined by senescence-associated β-gal staining. We found that SEA increased the expression of P27 protein, whereas it inhibited the expression of SKP2 and FoxO3a. Knockdown of P27 as well as overexpression of SKP2 both suppressed the SEA-induced senescence of HSCs. In addition, the nuclear translocation of FoxO3a from the nucleus to the cytoplasm was induced by SEA stimulation., Conclusions/significance: The present study demonstrates that SEA promotes HSCs senescence through the FoxO3a/SKP2/P27 pathway., Competing Interests: The authors have declared that no competing interests exist.

Independent of their etiology, all chronic liver diseases ultimately lead to liver cirrhosis, which is a major health problem worldwide. The underlying molecular mechanisms are still poorly understood and no efficient treatment strategies are available. This paper introduces the sinusoidal pressure hypothesis (SPH), which identifies an elevated sinusoidal pressure (SP) as cause of fibrosis. SPH has been mainly derived from recent studies on liver stiffness. So far, pressure changes have been exclusively seen as a consequence of cirrhosis. According to the SPH, however, an elevated SP is the major upstream event that initiates fibrosis via biomechanic signaling by stretching of perisinusoidal cells such as hepatic stellate cells or fibroblasts (SPH part I: initiation). Fibrosis progression is determined by the degree and time of elevated SP. The SPH predicts that the degree of extracellular matrix eventually matches SP with critical thresholds > 12 mmHg and > 4 wk. Elevated arterial flow and final arterialization of the cirrhotic liver represents the self-perpetuating key event exposing the low-pressure-organ to pathologically high pressures (SPH part II: perpetuation). It also defines the "point of no return" where fibrosis progression becomes irreversible. The SPH is able to explain the macroscopic changes of cirrhotic livers and the uniform fibrotic response to various etiologies. It also opens up new views on the role of fat and disease mechanisms in other organs. The novel concept will hopefully stimulate the search for new treatment strategies., Competing Interests: Conflict-of-interest statement: No conflict of interest to report.

Hepatic fibrosis is a naturally occurring wound-healing reaction, with an imbalance of extracellular matrix (ECM) during tissue repair response, which can further deteriorate to hepatocellular carcinoma without timely treatment. Inhibiting activated hepatic stellate cell (HSC) proliferation and inducing apoptosis are the main methods for the treatment of liver fibrosis. In our previous study, we found that the TOA-glycine derivative (G-TOA) had exhibited more significant inhibitory activity against HepG2 cells and better hydrophilicity than TOA, ligustrazine (TMP), and oleanolic acid (OA). However, inhibiting activated HSC proliferation and inducing apoptosis by G-TOA had not been reported. In this paper, the selective cytotoxicity of G-TOA was evaluated on HSC-T6 cells and L02 cells, and apoptosis mechanisms were explored. It was found that G-TOA could selectively inhibit the proliferation of activated HSC-T6 cells, induce morphological changes, early apoptosis, and mitochondrial membrane potential depolarization, increase intracellular free calcium levels, downregulate the expression of NF-κB/p65 and COX-2 protein, and decrease the ratio of Bcl-2/Bax, thereby inducing HSC-T6 cell apoptosis. Thence, G-TOA might be a potential antifibrosis agent for the therapy of hepatic fibrosis, provided that it exerts anti-fibrosis effects on activated HSC-T6 cells.