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Background: Absent in melanoma 2 (AIM2) inflammasome-dependent pyroptosis and neutrophil extracellular traps (NETs) have been implicated in chronic liver disease (CLD). However, the specific intrahepatic cell type that undergoes AIM2 inflammasome-dependent pyroptosis and how their interaction augments hepatic inflammation/fibrosis remains unclear., Methods: The expression and correlation of AIM2 inflammasome-dependent pyroptosis-related indicators and NETs were analyzed in biopsy tissue and blood specimens from chronic hepatitis patients (CHs). Cell-based experiments were conducted to investigate their interaction. In vitro and in vivo experiments were used to analyze their effects on the progression of hepatic inflammation/fibrosis as well as their clinical importance., Results: Elevated levels of AIM2 inflammasome-dependent pyroptosis indicators and NETs were detected in biopsy tissue and blood specimens. Circulating NETs were positively correlated with pyroptosis-related indicators, and both were related with disease severity. Confocal imaging revealed that AIM2 was mainly localized to hepatic macrophages, indicating that hepatic macrophages were the major cell type that underwent pyroptosis. NETs were directly engulfed by macrophages and then stimulated AIM2 inflammasome-dependent macrophage pyroptosis in vitro, which amplified the activation of hepatic stellate cells (HSCs) and increased collagen deposition. Administration of the NETs degradation agent DNase I or the AIM2 inflammasome activation inhibitor ODN A151 effectively alleviated chronic liver inflammation/fibrosis progression in vivo., Conclusions: NETs-induced AIM2 inflammasome-dependent pyroptosis in macrophages facilitates liver inflammation/fibrosis progression. The identified NET-AIM2 inflammasome cascade could serve as a novel therapeutic target for hepatic inflammation/fibrosis progression., Competing Interests: Declarations. Ethics approval and consent to participate: This study was approved by the Ethical Committee of the Second Hospital Affiliated with Chongqing Medical University (No. 2023–019). Consent for publication: All listed authors consent to the submission, and all data are used with the consent of the person generating the data. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

This study aims to explore the regulating effect and mechanism of naringenin (NGN) on the hepatic stellate cells (HSCs) apoptosis and its preventive effects on MASH fibrosis. C57BL/6 mice were subjected to either high-fat diet (HFD) plus carbon tetrachloride (CCl 4 ) injection (HFD + CCl 4 ) for 8 weeks to induce a MASH fibrosis model or bile duct ligation (BDL) to establish a liver fibrosis model, NGN was administered by gavage. LX2 cells were stimulated by oleic acid (OA) and lipopolysaccharide (LPS) (OA + LPS) to study the effects of NGN on activated hepatic stellate cell (HSC). Additionally, LO2 cells stimulated with OA + LPS were used to assess the protective effects of NGN on lipotoxicity of hepatocytes. Our in vivo results showed that NGN administration effectively inhibited mouse liver fibrosis in both of the MASH model and BDL model. The in vitro results indicate that NGN directly inhibited HSCs activation and promoted apoptosis of the activated HSCs, while it suppressed the apoptosis of LO2 cells induced by OA + LPS. The underlying mechanisms were mainly elucidated through the reduction of TAK1 phosphorylation, leading to the downregulation of p-JNK and p-ERK expression. This in turn, inhibited the phosphorylation of FoxO3a and promoted the nuclear localization of FoxO3a. Consequently, this may enhance the transcription of apoptosis-related genes, resulting in the apoptosis of activated HSCs. In conclusion, NGN ameliorates MASH fibrosis by enhancing apoptosis of the activated HSCs. The inhibitory effects of NGN on the TAK1/MAPK/FoxO3a pathway were demonstrated as its preventive mechanisms against MASH fibrosis., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Rong Qi reports was provided by National Natural Science Foundation of China. If there are other authors, they 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 © 2024 Elsevier Inc. All rights reserved.)

Hepatic stellate cells (HSCs) are pericytes of the liver responsible for liver fibrosis and cirrhosis, which are the end stages of chronic liver diseases. TGF-β activates HSCs, leading to the differentiation of myofibroblasts in the process of liver fibrosis. While the heterogeneity of HSCs is appreciated in the fibrotic liver, it remains elusive which HSC subsets mainly contribute to fibrosis. Here, we show that the expression of the pericyte marker FoxD1 specifically marks a subset of HSCs in FoxD1-fate tracer mice. HSCs fate-mapped by FoxD1 were preferentially localized in the portal and peripheral areas of both the homeostatic and fibrotic liver induced by carbon tetrachloride. Furthermore, the deletion of Cbfβ, which is necessary for TGF-β signaling, in FoxD1-expressing cells ameliorated liver fibrosis. Thus, we identified an HSC subset that preferentially responds to liver injuries., 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 © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Ageing is an inevitable and multifaceted biological process that impacts a wide range of cellular and molecular mechanisms, leading to the development of various diseases, such as liver fibrosis. Liver fibrosis progresses to cirrhosis, which is an advanced form due to high amounts of extracellular matrix and restoration of normal liver structure with failure to repair damaged tissue and cells, marking the end of liver function and total liver failure, ultimately death. The most important factors are reactive oxygen species (ROS) and cellular senescence. Oxidative stress is defined as an impairment by ROS, which are by-products of the mitochondrial electron transport chain and other key molecular pathways that induce cell damage and can activate cellular senescence pathways. Cellular senescence is characterized by pro-inflammatory cytokines, growth factors, and proteases secreted by senescent cells, collectively known as the senescence-associated secretory phenotype (SASP). The presence of senescent cells, which disrupt tissue architecture and function and increase senescent cell production in liver tissues, contributes to fibrogenesis. Hepatic stellate cells (HSCs) are activated in response to chronic liver injury, oxidative stress, and senescence signals that drive excessive production and deposition of extracellular matrix. This review article aims to provide a comprehensive overview of the pathogenic role of ROS and cellular senescence in the aging liver and their contribution to fibrosis., Competing Interests: Declarations Competing interest The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Liver fibrosis, a common feature of most chronic liver diseases, poses significant health risks and results from various etiologies. While microRNAs (miRNAs) have demonstrated promising anti-fibrotic potential through the direct regulation of target genes, their therapeutic mechanisms remain incompletely understood. In this study, we identified miR-199a, initially discovered in anti-liver fibrotic exosomes, as a key modulator that alleviates thioacetamide-induced liver fibrosis in a mouse model. Consistent with its in vivo effects, treatment with an miR-199a mimic effectively inhibited the activation and function of human hepatic stellate cells (HSCs)-central drivers of liver fibrosis-as well as HSC proliferation and viability in vitro. Notably, miR-199a-3p exerted these anti-fibrotic effects by directly downregulating its biologically relevant target, cyclin-dependent kinase 17 (CDK17). Depletion of CDK17 alone in activated HSCs was sufficient to suppress their activation, function, proliferation, and viability, mirroring the effects of miR-199a mimic treatment. Conversely, overexpression of CDK17 reversed all cellular effects induced by miR-199a mimic treatment. Our findings highlight the miR-199a-3p-CDK17 regulatory axis and suggest that targeting CDK17 in activated HSCs could be a promising therapeutic strategy for liver fibrosis., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: SIRT7 is a class III HDACs deacetylase which plays critical roles in various biological processes. Aberrant SIRT7 expression is associated with tumorigenesis and disease progression while role of SIRT7 in hepatic fibrosis remain elusive., Methods: SIRT7 expression was examined in fibrotic liver sample via WB and IHC. Myeloid cell-specific knockout (SIRT7 MKO ) mice were generated by crossing SIRT7 flox/flox mice with LysM-Cre mice. Primary hepatic stellate cells (HSCs) was isolated to examine stellate cells activation. SIRT7 and SMAD2/3 interaction were analyzed by immunoprecipitation. SB525334 was used to prevent SMAD2/3 phosphorylation., Results: SIRT7 expression was decreased during chronic liver disease progression but was increased in liver cancer. IHC staining indicated that SIRT7 was primarily expressed in non-parenchymal cells in both fibrotic and cirrhotic liver. Knockout SIRT7 in myeloid cells resulted in significant elevation of serum ALT and liver fibrosis, but mildly affected hepatic inflammation after CCl4 treatment. We further observed significant elevation of elevation of stellate cell activation and SMAD2/3 activation in SIRT7 MKO mice. By using primary HSCs and stellate cell line, we confirmed that SIRT7 interacted with SMAD2/3, induced its deacetylation and was critical in regulation of SMAD2/3 activation and stellate cell activation upon TGF-β stimulation. Pharmacological inhibition of SMAD2/3 reversed the hyperactivation of SIRT7 MKO HSCs after TGF-β stimulation, and abolished stellate cell activation and liver fibrosis in SIRT7 MKO mice., Conclusion: Our findings revealed previously unidentified role of SIRT7 in regulating HSCs activation via modulating TGF-β/SMAD2/3 signaling pathway. Targeting SIRT7 might offer novel therapeutic option against liver fibrosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no affiliations with or involvement in any organization or entity with any financial interest in the subject matter or materials discussed in this manuscript., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Gaudichaudione H (GH) is a natural small molecular compound isolated from Garcinia oligantha Merr. (Clusiaceae). Being an uncommon rare caged polyprenylated xanthone, the potential pharmacological functions of GH remain to be fully elucidated currently. In this study, we primarily focused on identifying potential bioavailable targets and elucidating related therapeutic actions. Herein, the network pharmacology analysis, metabolomics analysis and genome-wide mRNA transcription assay were performed firstly to predict the major pharmacological action and potential targets of GH. To confirm the hypothesis, gene knockout model was created using CRISPR/Cas9 method. The pharmacological action of GH was evaluated in vitro and in vivo. Firstly, our results of network pharmacology analysis and omics assay indicated that GH significantly activated NRF2 signaling pathway, and the function could be associated with liver disease treatment. Then, the pharmacological action of GH was evaluated in vitro and in vivo. The treatment with GH significantly increased the protein levels of NRF2 and promoted the transcription of NRF2 downstream genes. Further analysis suggested that GH regulated NRF2 through an autophagy-mediated non-canonical mechanism. Additionally, the administration of GH effectively protected the liver from carbon tetrachloride (CCl 4 )-induced liver fibrosis and inflammation, which depended on the activation of NRF2 in hepatic stellate cells and inflammatory cells respectively. Collectively, our findings underscore the potential therapeutic effect of GH on alleviating hepatic fibrosis and inflammation through the augmentation of NRF2 signaling pathway, providing a promising avenue for the treatment of liver fibrosis and inflammation in clinical settings., 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 © 2024 Elsevier Inc. All rights reserved.)

This study evaluated the cellular heterogeneity and molecular mechanisms of hepatocellular carcinoma (HCC). Single cell RNA sequencing (scRNA-seq), transcriptomic data, histone lactylation-related genes were collected from public databases. Cell-cell interaction, trajectory, pathway, and spatial transcriptome analyses were executed. Differential expression and survival analyses were conducted. Western blot, Real-time reverse transcription PCR (qRT-PCR), and Cell Counting Kit 8 (CCK8) assay were used to detect the expression of αSMA, AKR1B10 and its target genes, and verify the roles of AKR1B10 in HCC cells. Hepatic stellate cell (HSC) subgroups strongly interacted with tumor cell subgroups, and their spatial distribution was heterogeneous. Two candidate prognostic genes (AKR1B10 and RMRP) were obtained. LONP1, NPIPB3, and ZSWIM6 were determined as AKR1B10 targets. Besides, the expression levels of AKR1B10 and αSMA were significantly increased in LX-2 + HepG2 and LX-2 + HuH7 groups compared to those in LX-2 group, respectively. sh-AKR1B10 significantly inhibited the HCC cell proliferation and change the expression of AKR1B10 target genes, Bcl-2, Bax, Pan Kla, and H3K18la at protein levels. Our findings unveil the pivotal role of HSCs in HCC pathogenesis through regulating histone lactylation., 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 © 2024 Elsevier B.V. All rights reserved.)

Hepatic stellate cells (HSCs) play a role in hepatic fibrosis and sphingosine kinase (SphK) is involved in biological processes. As studies on the regulatory mechanisms and functions of SphK in HSCs during liver fibrosis are currently limited, this study aimed to elucidate the regulatory mechanism and connected pathways of SphK upon HSC activation. The expression of SphK1 was higher in HSCs than in hepatocytes, and upregulated in activated primary HSCs. SphK1 was also increased in liver homogenates of carbon tetrachloride-treated or bile duct ligated mice and in transforming growth factor-β (TGF-β)-treated LX-2 cells. TGF-β-mediated SphK1 induction was due to Smad3 signaling in LX-2 cells. SphK1 modulation altered the expression of liver fibrogenesis-related genes. This SphK1-mediated profibrogenic effect was dependent on SphK1/sphingosine-1-phosphate/sphingosine-1-phosphate receptor signaling through ERK. Epigallocatechin gallate blocked TGF-β-induced SphK1 expression and hepatic fibrogenesis by attenuating Smad and MAPK activation. SphK1 induced by TGF-β facilitates HSC activation and liver fibrogenesis, which is reversed by epigallocatechin gallate. Accordingly, SphK1 and related signal transduction may be utilized to treat 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 © 2024 Elsevier Inc. All rights reserved.)

Primary biliary cholangitis (PBC) is a chronic autoimmune liver disease characterized by multilineage immune dysregulation, which subsequently causes inflammation, fibrosis, and even cirrhosis of liver. Due to the limitation of traditional assays, the local hepatic immunopathogenesis of PBC has not been fully characterized. Here, we utilize single-cell RNA sequencing technology to depict the immune cell landscape and decipher the molecular mechanisms of PBC patients. We reveal that cholangiocytes and hepatic stellate cells are involved in liver inflammation and fibrosis. Moreover, Kupffer cells show increased levels of inflammatory factors and decreased scavenger function related genes, while T cells exhibit enhanced levels of inflammatory factors and reduced cytotoxicity related genes. Interestingly, we identify a liver-resident Th1-like population with JAK-STAT activation in the livers of both PBC patients and murine PBC model. Finally, blocking the JAK-STAT pathway alleviates the liver inflammation and eliminates the liver-resident Th1-like cells in the murine PBC model. In conclusion, our comprehensive single-cell transcriptome profiling expands the understanding of pathological mechanisms of PBC and provides potential targets for the treatment of PBC in patients., (© 2024. The Author(s).)

Background: Cirrhosis leads to portal hypertension (PHT), affecting survival with limited treatment options. This study investigated Imperatorin (IMP), a furanocoumarin with anti-inflammatory and hypotensive properties, for its therapeutic role and mechanisms in cirrhotic PHT., Methods: Hepatic stellate cells (HSCs) inhibition by IMP was evaluated using LX-2 cell line. Rat cirrhosis was induced via CCl 4 for 16 weeks. Experimental group were orally administered IMP (15/25 mg/kg/day) for 4 weeks. We subsequently examined portal pressure (PP), cirrhosis, inflammation, angiogenesis, and vascular remodeling. Network pharmacology was employed for mechanistic insights., Results: IMP significantly inhibited the fibrogenesis in HSCs and suppressed cell viability. CCl 4 exposure induced cirrhosis, inflammation, angiogenesis, vascular remodeling and PHT. IMP significantly reduced PP from 22.85 ± 3.88 mmHg to 6.67 ± 0.6 mmHg, diminished collagen deposition and pro-fibrotic factor expression, alleviated inflammation, and improved liver function. Vessel wall thickness in superior mesenteric arteries was restored, and intra-/extrahepatic angiogenesis was inhibited via VEGF and vWF. Furthermore, IMP induced sinusoidal vasodilation by upregulating eNOS and GCH1. Enrichment analysis indicated that IMP was involved in various biological processes associated with cirrhosis, such as the regulation of blood pressure, tissue remodeling, response to inflammation, and regulation of angiogenesis, etc. Additionally, IMP suppressed hepatic expression of TGF-β both in vitro and in vivo, which was further supported by KEGG analysis., Conclusion: Our research demonstrated that IMP significantly mitigated cirrhosis PHT by reducing hepatic fibrosis and inflammation, curbing angiogenesis and vascular remodeling, and promoting vasodilation. This protective mechanism appears to be facilitated through the downregulation of TGF-β., 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 © 2024. Published by Elsevier B.V.)

The peptide hormone kisspeptin attenuates liver steatosis, metabolic dysfunction-associated steatohepatitis (MASH), and fibrosis in mouse models by signaling via the kisspeptin 1 receptor (KISS1R). However, whether kisspeptin impacts fibrogenesis in the human liver is not known. We investigated the impact of a potent kisspeptin analog (KPA) on fibrogenesis using human precision-cut liver slices (hPCLS) from fibrotic livers from male patients, in human hepatic stellate cells (HSCs), LX-2, and in primary mouse HSCs. In hPCLS, 48 h and 72 h of KPA (3 nM, 100 nM) treatment decreased collagen secretion and lowered the expression of fibrogenic and inflammatory markers. Immunohistochemical studies revealed that KISS1R is expressed and localized to HSCs in MASH/fibrotic livers. In HSCs, KPA treatment reduced transforming growth factor b (TGFβ)-the induced expression of fibrogenic and inflammatory markers, in addition to decreasing TGFβ-induced collagen secretion, cell migration, proliferation, and colony formation. Mechanistically, KISS1R signaling downregulated TGFβ signaling by decreasing SMAD2/3 phosphorylation via the activation of protein phosphatases, PP2A, which dephosphorylates SMAD 2/3. This study revealed for the first time that kisspeptin reverses human hepatic fibrogenesis, thus identifying it as a new therapeutic target to treat hepatic fibrosis.

Schistosomiasis affects over 250 million people worldwide, with the highest prevalence at the age of 10-14 years. The influence of the host's age on the severity of liver damage is unclear. We infected male 8, 14, and 20-week-old mice with S. mansoni . Hepatic damage, inflammation, fibrosis, and metabolism were analyzed by RT-qPCR, Western blotting, ELISA, immunohistochemistry, and mechanistic transwell chamber experiments using S. mansoni eggs and human hepatic stellate cells (HSCs) or primary mouse hepatocytes. Major results were validated in human biopsies. We found that hepatosplenomegaly, granuloma size, egg load, inflammation, fibrosis, and glycogen stores all improved with the increasing age of the host. However, serum alanine transaminase (ALT) levels were lowest in young mice infected with S. mansoni . Hepatic carbohydrate exploitation was characterized by a shift towards Warburg-like glycolysis in S. mansoni -infected animals. Notably, S. mansoni eggs stimulated hepatic stellate cells to an alternatively activated phenotype (GFAP + /desmin + /αSMA - ) that secretes IL-6 and MCP-1. The reduction of fibrosis in older age likely depends on the fine-tuning of regulatory and inflammatory cytokines, alternative HSC activation, and the age-dependent preservation of hepatic energy stores. The current results emphasize the significance of investigations on the clinical relevance of host age-dependent liver damage in patients with schistosomiasis.

Liver fibrosis, which is caused by viral infection, toxic exposure, and autoimmune diseases, is a chronic liver disease. Plasminogen activator inhibitor-1 (PAI-1) is a serine protease inhibitor of tissue-type plasminogen activator (tPA) and urokinase plasminogen activator, which convert plasminogen into plasmin. Therefore, PAI-1 suppresses fibrinolysis by blocking plasmin synthesis and is involved in liver fibrosis via extracellular matrix deposition. Small leucine zipper protein (sLZIP) acts as a transcription factor and plays critical roles in many cellular processes. However, the role of sLZIP in liver fibrosis remains unclear. In this study, we investigated the role of sLZIP in regulating PAI-1 transcription and liver fibrosis. sLZIP knockdown enhanced the expression of PAI-1 at the mRNA and protein levels. sLZIP knockdown also increased PAI-1 secretion and suppressed blood clot lysis by blocking tPA activity. Moreover, conditioned medium derived from sLZIP knockdown cells downregulated the expression of matrix metalloprotease (MMP)-2 and MMP-9 in the presence of tPA in hepatic stellate cells (HSCs). Liver-specific sLZIP knockout mice showed deteriorated liver fibrosis compared to control mice in a bile duct ligation-induced fibrosis model. These findings demonstrate that sLZIP functions as a negative regulator of liver fibrosis by suppressing PAI-1 transcription and HSC activation., Competing Interests: Declaration of competing interest We confirm that all authors fulfill all conditions required for authorship. We also confirm that there is no potential conflict of interest as described in the Instruction for Authors. All authors have read and approved the manuscript., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background & Aims: Activation of hepatic stellate cells (HSCs) is the key process underlying liver fibrosis. Unveiling its molecular mechanism may provide an effective target for inhibiting liver fibrosis. Protein ubiquitination is a dynamic and reversible process. Deubiquitinases (DUBs) catalyze the removal of ubiquitin chains from substrate proteins, thereby inhibiting the biological processes regulated by ubiquitination signals. However, there are few studies revealing the role of deubiquitination in the activation of HSCs., Methods & Results: Single-cell RNA sequencing (scRNA-seq) revealed significantly decreased USP18 expression in activated HSCs when compared to quiescent HSCs. In mouse primary HSCs, continuous activation of HSCs led to a gradual decrease in USP18 expression whilst restoration of USP18 expression significantly inhibited HSC activation. Injection of USP18 lentivirus into the portal vein of a CCl 4 -induced liver fibrosis mouse model confirmed that overexpression of USP18 can significantly reduce the degree of liver fibrosis. In terms of mechanism, we screened some targets of USP18 in mouse primary HSCs and found that USP18 could directly bind to TAK1. Furthermore, we demonstrated that USP18 can inhibit TAK1 activity by interfering with the K63 ubiquitination of TAK1., Conclusions: Our study demonstrated that USP18 inhibited HSC activation and alleviated liver fibrosis via modulation of TAK1 activity; this may prove to be an effective target for inhibiting liver fibrosis., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024. Published by Elsevier Inc.)

A series of 2,6,9-trisubstituted purine derivatives were designed and synthesized with diverse chemical moieties. Through a comprehensive biological evaluation, we identified 4-(6-(methylamino)-2-(phenylethynyl)-9H-purin-9-yl)phenol (6a) as a promising A 2A AR antagonist with potent antifibrotic properties. Compound 6a demonstrated significant efficacy in inhibiting CRE promoter activity and in reducing the expression of fibrogenic marker proteins and downstream effectors of A 2A AR activation, surpassing the A 2A AR antagonist ZM241385 and initial screening hits, 9-benzyl-N-methyl-2-(phenylethynyl)-9H-purin-6-amine (5a) and 9-((benzyloxy)methyl)-N-methyl-2-(phenylethynyl)-9H-purin-6-amine (5j). Further validation revealed that compound 6a effectively inhibited fibrogenic marker proteins induced by A 2A AR overexpression or TGF-β1 treatment in hepatic stellate cells, alongside reducing PKA and CREB phosphorylation. These findings suggest that compound 6a exerts its antifibrotic action by modulating the cAMP/PKA/CREB pathway through A 2A AR inhibition. Overall, our study provides valuable insights for the development of novel therapeutics that target hepatic fibrosis through A 2A AR antagonism., 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 © 2024. Published by Elsevier Ltd.)

The role of peroxisome proliferator-activated receptor (PPAR)β/δ in hepatic fibrosis remains a subject of debate. Here, we examined the effects of a PPARβ/δ agonist on the pathogenesis of liver fibrosis and the activation of hepatic stellate cells (HSCs), the main effector cells in liver fibrosis, in response to the pro-fibrotic stimulus transforming growth factor-β (TGF-β). The PPARβ/δ agonist GW501516 completely prevented glucose intolerance and peripheral insulin resistance, blocked the accumulation of collagen in the liver, and attenuated the expression of inflammatory and fibrogenic genes in mice fed a choline-deficient high-fat diet (CD-HFD). The antifibrogenic effect of GW501516 observed in the livers CD-HFD-fed mice could occur through an action on HSCs since primary HSCs isolated from Ppard -/- mice showed increased mRNA levels of the profibrotic gene Col1a1. Moreover, PPARβ/δ activation abrogated TGF-β1-mediated cell migration (an indicator of cell activation) in LX-2 cells (immortalized activated human HSCs). Likewise, GW501516 attenuated the phosphorylation of the main downstream intracellular protein target of TGF-β1, suppressor of mothers against decapentaplegic (SMAD)3, as well as the levels of the SMAD3 co-activator p300 via the activation of AMP-activated protein kinase (AMPK) and the subsequent inhibition of extracellular signal-regulated kinase-1/2 (ERK1/2) in LX-2 cells. Overall, these findings uncover a new mechanism by which the activation of AMPK by a PPARβ/δ agonist reduces TGF-β1-mediated activation of HSCs and fibrosis via the reduction of both SMAD3 phosphorylation and p300 levels., Competing Interests: Declaration of Competing Interest None., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Nonalcoholic fatty liver disease (NAFLD) is a liver disease causing different progressive pathological changes. Trimethylamine N-oxide (TMAO), a product of gut microbiota metabolism, is a specific agonist of the protein kinase R-like endoplasmic reticulum kinase (PERK) pathway, one of the endoplasmic reticulum stress (ERS) pathways. TMAO has been associated with the occurrence and development of NAFLD based on the results of previous studies, but whether the simple consumption of TMAO can directly induce NAFLD and its underlying mechanism remain unclear. To investigate this question, we constructed an animal model in which adult male zebrafish were fed a controlled diet containing 1 % or 3 % TMAO for 20 weeks. Eventually, we observed that TMAO caused lipid accumulation, inflammatory infiltration, liver injury and liver fibrosis in zebrafish livers; meanwhile, the PERK signaling pathway was activated in the zebrafish livers. This finding was further confirmed in HepG2 cells and hepatic stellate cells models. In conclusion, this study found that TMAO directly induced different pathological states of NAFLD in zebrafish liver, and the activation of PERK pathway is an important mechanism, which may provide crucial strategies for the diagnosis and treatment of NAFLD., 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 © 2024 Elsevier B.V. All rights reserved.)

Background & Aims: Toll-like receptor 9 (Tlr9) is a pathogen recognition receptor detecting unmethylated DNA derivatives of pathogens and damaged host cells. It is therefore an important modulator of innate immunity. Here we investigated the role of Tlr9 in fibrogenesis and progression of hepatocellular carcinoma in chronic liver disease., Materials and Methods: We treated mice with a constitutive deletion of Tlr9 (Tlr9 -/- ) with DEN/CCl 4 for 24 weeks. As a second model, we used hepatocyte-specific Nemo knockout (Nemo Δhepa ) mice and generated double knockout (Nemo Δhepa Tlr9 -/- ) animals., Results: We show that Tlr9 is in the liver primarily expressed in Kupffer cells, suggesting a key role of Tlr9 in intercellular communication during hepatic injury. Tlr9 deletion resulted in reduced liver fibrosis as well as tumor burden. We observed down-regulation of hepatic stellate cell activation and consequently decreased collagen production in both models. Tlr9 deletion was associated with decreased apoptosis and compensatory proliferation of hepatocytes, modulating the initiation and progression of hepatocarcinogenesis. These findings were accompanied by a decrease in interferon-β and an increase in chemokines having an anti-tumoral effect., Conclusions: Our data define Tlr9 as an important receptor involved in fibrogenesis, but also in the initiation and progression of hepatocellular carcinoma during chronic liver diseases., 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 © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

The mechanisms underlying the remarkable capacity of the liver to regenerate are still not completely understood. Particularly, the cross-talk between cytokines and cellular components of the process is of utmost importance because they represent potential avenues for diagnostics and therapeutics. WNT1-inducible-signaling pathway protein 1 (WISP1) is a cytokine member of the CCN family, a family of proteins that play many different roles in liver pathophysiology. WISP1 also belongs to the earliest and strongest upregulated genes in mouse livers after CCl 4 intoxication and has recently been shown to be secreted by tumor cells and to bind to type 1 collagen to cause its linearization in vitro and in tumor tissue in vivo. We show that WISP1 expression is strongly induced by TGFβ, a critical cytokine in wound healing processes. Additionally, secretion of WISP1 protein by hepatic stellate is increased in cells upon TGFβ stimulation (~seven-fold increase). Furthermore, WISP1 facilitates the migration of mouse hepatic stellate cells through collagen in vitro. However, in WISP1 knockout mice, no difference in stellate cell accumulation in damaged liver tissue and no influence on fibrosis was obtained, probably because the knockout of WISP1 was compensated by other factors in vivo.

Activation of extracellular matrix-producing hepatic stellate cells (HSCs) is a key event in liver fibrogenesis. We showed that the expression of the heme-thiolate monooxygenase cytochrome P450 1B1 (CYP1B1) was elevated in human and mouse fibrotic livers and activated HSCs. Systemic or HSC-specific ablation and pharmacological inhibition of CYP1B1 attenuated HSC activation and protected male but not female mice from thioacetamide (TAA)-, carbon tetrachloride (CCl 4 )-, or bile duct ligation (BDL)-induced liver fibrosis. Metabolomic analysis revealed an increase in the disaccharide trehalose in CYP1B1-deficient HSCs resulting from intestinal suppression of the trehalose-metabolizing enzyme trehalase, whose gene we found to be a target of RARα. Trehalose or its hydrolysis-resistant derivative lactotrehalose exhibited potent antifibrotic activity in vitro and in vivo by functioning as an HSC-specific autophagy inhibitor, which may account for the antifibrotic effect of CYP1B1 inhibition. Our study thus reveals an endobiotic function of CYP1B1 in liver fibrosis in males, mediated by liver-intestine cross-talk and trehalose. At the translational level, pharmacological inhibition of CYP1B1 or the use of trehalose/lactotrehalose may represent therapeutic strategies for liver fibrosis.

Pregnane X receptor (PXR) is a xenobiotic-sensing nuclear receptor that plays a key role in drug metabolism. Recently, PXR was found to attenuate the development of liver cancer by suppressing epithelial-mesenchymal transition (EMT) in liver cancer cells in a mouse model of two-stage chemical carcinogenesis. To elucidate the role of PXR in the EMT of liver cancer cells, we focused on its role in hepatic stellate cells (HSCs), which are components of the tumor microenvironment in hepatocellular carcinoma (HCC). Human HSC-derived LX-2 cells stably expressed destabilization domain (DD)-fused human PXR (hPXR-LX2 cells). Human HCC-derived HepG2 cells were transfected with the EMT marker VIM promoter-regulated reporter plasmid and co-cultured with hPXR-LX2 cells or treated with hPXR-LX2-derived conditioned medium (CM). Co-culture or CM treatment increased reporter activity in HepG2 cells. This induction was attenuated upon PXR activation in hPXR-LX2 cells by treatment with the DD-stabilizing chemical Shield-1 and the human PXR ligand rifampicin. PXR activation in hPXR-LX2 cells exhibited inhibition of TGF-β1-induced transdifferentiation, supported by observations of morphological changes and protein or mRNA levels of the transdifferentiation markers COL1A1 and FN1. PXR activation in hPXR-LX2 cells also attenuated the mRNA levels of the key transdifferentiation factor, POSTN. Treatment of hPXR-LX2 cells with recombinant POSTN restored the PXR-mediated suppression of transdifferentiation. Reporter assays with the POSTN promoter showed that PXR inhibited the NF-κB-mediated transcription of POSTN. Consequently, PXR activation in HSCs is expected to inhibit transdifferentiation by down-regulating POSTN expression, thereby suppressing EMT of liver cancer cells., (© 2024 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.)

Background: The tumor microenvironment (TME) exerts profound effects on tumor progression and therapeutic efficacy. In hepatocellular carcinoma (HCC), the TME is enriched with cancer-associated fibroblasts (CAFs), which secrete a plethora of cytokines, chemokines, and growth factors that facilitate tumor cell proliferation and invasion. However, the intricate architecture of the TME in HCC, as well as the mechanisms driving interactions between tumor cells and CAFs, remains largely enigmatic., Methods: We analyzed 10 spatial transcriptomics and 12 single-cell transcriptomics samples sourced from public databases, complemented by 20 tumor tissue samples from liver cancer patients obtained in a clinical setting., Results: Our findings reveal that tumor cells exhibiting high levels of SPP1 are preferentially localized adjacent to hepatic stellate cells (HSCs). The SPP1 secreted by these tumor cells interacts with the CD44 receptor on HSCs, thereby activating the PI3K/AKT signaling pathway, which promotes the differentiation of HSCs into CAFs. Notably, blockade of the CD44 receptor effectively abrogates this interaction. Furthermore, in vivo studies demonstrate that silencing SPP1 expression in tumor cells significantly impairs HSC differentiation into CAFs, leading to a reduction in tumor volume and collagen deposition within the tumor stroma., Conclusions: This study delineates the SPP1-CD44 signaling axis as a pivotal mechanism underpinning the interaction between tumor cells and CAFs. Targeting this pathway holds potential to mitigate liver fibrosis and offers novel therapeutic perspectives for liver cancer management., (© 2024. The Author(s).)

Background: Dysregulated lipid oxidation occurs in several pathological processes characterized by cell proliferation and migration. Nonetheless, the molecular mechanism of lipid oxidation is not well appreciated in liver fibrosis, which is accompanied by enhanced fibroblast proliferation and migration., Methods: We investigated the causes and consequences of lipid oxidation in liver fibrosis using cultured cells, animal models, and clinical samples., Results: Increased ecto-nucleotide pyrophosphatase/phosphodiesterase (ENPP1) expression caused increased lipid oxidation, resulting in the proliferation and migration of hepatic stellate cells (HSCs) that lead to liver fibrosis, whereas fibroblast-specific ENPP1 knockout reversing these results. Elevated ENPP1 and N 6 -methyladenosine (m 6 A) levels were associated with high expression of Wilms tumor 1 associated protein (WTAP). Mechanistically, WTAP-mediated m 6 A methylation of the 3'UTR of ENPP1 mRNA and induces its translation dependent of YTH domain family proteins 1 (YTHDF1). Additionally, ENPP1 could interact with hypoxia inducible lipid droplet associated (HILPDA) directly; overexpression of ENPP1 further recruits HILPDA-mediated lipid oxidation, thereby promotes HSCs proliferation and migration, while inhibition of ENPP1 expression produced the opposite effect. Clinically, increased expression of WTAP, YTHDF1, ENPP1, and HILPDA, and increased m 6 A mRNA content, enhanced lipid oxidation, and increased collagen deposition in human liver fibrosis tissues., Conclusions: We describe a novel mechanism in which WTAP catalyzes m 6 A methylation of ENPP1 in a YTHDF1-dependent manner to enhance lipid oxidation, promoting HSCs proliferation and migration and liver fibrosis., (© 2024. The Author(s).)

Infection with Schistosoma japonicum (S. japonicum) is an important zoonotic parasitic disease that causes liver fibrosis in both human and domestic animals. The activation of hepatic stellate cells (HSCs) is a crucial phase in the development of liver fibrosis, and inhibiting their activation can alleviate this progression. Total flavonoids of litchi seed (TFL) is a naturally extracted drug, and modern pharmacological studies have shown its anti-fibrotic and liver-protective effects. However, the role of TFL in schistosomiasis liver fibrosis is still unclear. This study investigated the therapeutic effects of TFL on liver fibrosis in S. japonicum infected mice and explored its potential mechanisms. Animal study results showed that TFL significantly reduced the levels of Interleukin-1β (IL-1β), Tumor Necrosis Factor-α (TNF-α), Interleukin-4 (IL-4), and Interleukin-6 (IL-6) in the serum of S. japonicum infected mice. TFL reduced the spleen index of mice and markedly improved the pathological changes in liver tissues induced by S. japonicum infection, decreasing the expression of alpha-smooth muscle actin (α-SMA), Collagen I and Collagen III protein in liver tissues. In vitro studies indicated that TFL also inhibited the activation of HCSs induced by Transforming Growth Factor-β1 (TGF-β1) and reduced the levels of α-SMA. Gut microbes metagenomics study revealed that the composition, abundance, and functions of the mice gut microbiomes changed significantly after S. japonicum infection, and TLF treatment reversed these changes. Therefore, our study indicated that TFL alleviated granulomatous lesions and improved S. japonicum induced liver fibrosis in mice by inhibiting the activation of HSCs and by improving the gut microbiomes., Competing Interests: Declaration of Competing Interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work. There is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

The liver is innervated by primary sensory nerve fibres releasing the neuropeptide calcitonin gene-related peptide (CGRP). Elevated plasma levels of CGRP have been found in patients with liver fibrosis or cirrhosis. We hypothesised that signalling of CGRP and its receptors might regulate liver fibrosis and propose a novel potential target for the treatment. In this study, hepatic expression of CGRP and its receptor component, the receptor activity-modifying protein 1 (RAMP1), was dramatically increased in diseased livers of patients. In a murine liver fibrosis model, deficiency of RAMP1 resulted in attenuated fibrogenesis characterized by less collagen deposition and decreased activity of hepatic stellate cells (HSC). Mechanistically, activity of the TGFβ1 signalling core component Smad2 was severely impaired in the absence of RAMP1, and Yes-associated protein (YAP) activity was found to be diminished in RAMP1-deficient liver parenchyma. In vitro, stimulation of the HSC line LX-2 cells with CGRP induces TGFβ1 production and downstream signalling as well as HSC activation documented by increased α-SMA expression and collagen synthesis. We further demonstrate in LX-2 cells that CGRP promotes YAP activation and its nuclear translocation subsequent to TGFβ1/Smad2 signals. These data support a promotive effect of CGRP signalling in liver fibrosis via stimulation of TGFβ1/Smad2 and YAP activity., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: A two-way relationship exists between type 2 diabetes (T2DM) and human nonalcoholic steatohepatitis (NASH). Several diabetic NASH models have the disadvantages of long cycles or inconsistent with the actual incidence of human disease, which would be costly and time-consuming to investigate disease pathogenesis and develop drugs. Therefore, there is an urgent need to establish a diabetic NASH mouse model., Methods: The combination between Fructose-palmitate-cholesterol diet (FPC) and Streptozotocin (STZ) (FPC+STZ) was used to construct diabetic NASH mouse model. The in vivo effects of silencing acid-sensitive Ion Channel 1a (ASIC1a) were examined with an adeno-associated virus 9 (AAV9) carrying ASIC1a short hairpin RNA (shRNA) in FPC+STZ model., Results: The mice fed with FPC for 12 weeks had insulin resistance, hyperinsulinemia, lipid accumulation, and increased hepatic levels of inflammatory factors. However, it still did not develop remarkable liver fibrosis. Most interestingly, noticeable fibrotic scars were observed in the liver of mice from FPC+STZ group. Furthermore, insulin therapy significantly ameliorated FPC+STZ-induced NASH-related liver fibrosis, indicating that hyperglycemia is of great significance in NASH development and progression. Importantly, ASIC1a was found to be involved in the pathogenesis of diabetic NASH as demonstrated that silencing ASIC1a in HSCs significantly ameliorated FPC+STZ-induced NASH fibrosis. Mechanistically, ASIC1a interacted with Poly Adp-adenosine ribose polymerase (PARP1) to promote HSC activation by inducing autophagy., Conclusion: A FPC diet combined with an injection of STZ induces a diabetic NASH mouse model in a shorter period. Targeting ASIC1a may provide a novel therapeutic target for the treatment of diabetic NASH., Competing Interests: Declaration of Competing Interest The author declares that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Masson SAS.)

Hepatic stellate cells (HSCs) secrete extracellular matrix for collagen deposition, contributing to liver fibrosis. Ferroptosis is a novel type of programmed cell death induced by iron overload-dependent lipid peroxidation. Regulation of ferroptosis in hepatic stellate cells (HSCs) may have therapeutic potential for liver fibrosis. Here, we found that Maf bZIP transcription factor G (MafG) was upregulated in human and murine liver fibrosis. Interestingly, MafG knockdown increased HSCs ferroptosis, while MafG overexpression conferred resistance of HSCs to ferroptosis. Mechanistically, MafG physically interacted with non-muscle myosin heavy chain IIa (MYH9) to transcriptionally activate lipocalin 2 (LCN2) expression, a known suppressor for ferroptosis. Site-directed mutations of MARE motif blocked the binding of MafG to LCN2 promoter. Re-expression of LCN2 in MafG knockdown HSCs restored resistance to ferroptosis. In bile duct ligation (BDL)-induced mice model, we found that treatment with erastin alleviated murine liver fibrosis by inducing HSC ferroptosis. HSC-specific knowdown MafG based on adeno-associated virus 6 (AAV-6) improved erastin-induced HSC ferroptosis and alleviation of liver fibrosis. Taken together, MafG inhibited HSCs ferroptosis to promote liver fibrosis through transcriptionally activating LCN2 expression. These results suggest that MafG/MYH9-LCN2 signaling pathway could be a novel targets for the treatment of liver fibrosis., (© 2024. The Author(s), under exclusive licence to ADMC Associazione Differenziamento e Morte Cellulare.)

Liver fibrosis is a common pathological process in the progression of several chronic liver diseases to cirrhosis and hepatocellular carcinoma. Therefore, the development of medications that can repress the progress of liver fibrosis is essential. We discovered that initially, 12β-( m -methyl-benzoyl)-11,12-dihydro oleanolic acid (12d-OA), a farnesoid X receptor (FXR) modulator, possessed potential anti-fibrotic properties. Through an in-depth study, we revealed that 12d-OA not only inhibited the expression of fibrogenic markers in the LX-2 cells and HSC-T6 cells but also exhibited significant protective effects against liver injury and liver fibrosis in bile duct ligation (BDL) rats. Further exploration of its molecular mechanism indicated that 12d-OA exerted antifibrotic activity by inhibiting the extracellular signal-regulated kinase (ERK)/stress-activated protein kinase (p38) signaling pathways. Consequently, the great effects of 12d-OA in vitro and in vivo suggest that it may be a good candidate for liver fibrosis.

Objective: To explore the effect and mechanism of Dahuang Zhechong Pill (DHZCP) on liver fibrosis., Methods: Liver fibrosis cell model was induced by transforming growth factor-β (TGF-β) in hepatic stellate cells (HSC-T6). DHZCP medicated serum (DMS) was prepared in rats. HSC-T6 cells were divided into the control (15% normal blank serum culture), TGF-β (15% normal blank serum + 5 ng/mL TGF-β), DHZCP (15% DMS + 5 ng/mL TGF-β), DHZCP+PDTC [15% DMS + 4 mmol/L ammonium pyrrolidine dithiocarbamate (PDTC)+ 5 ng/mL TGF-β], and PDTC groups (4 mmol/L PDTC + 5 ng/mL TGF-β). Cell activity was detected by cell counting kit 8 and levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the cell supernatant were determined by enzyme-linked immunosorbnent assay. Western blot was used to measure the expressions of p38 mitogen-activated protein kinase/nuclear factor kappa B/transforming growth factor-β1 (p38 MAPK/NF-κ B/TGF-β1) pathway related proteins, and the localization and expressions of these proteins were observed by immunofluorescence staining., Results: DHZCP improves the viability of cells damaged by TGF-β and reduces inflammatory cytokines and ALT and AST levels in the supernatant of HSC-T6 cells induced with TGF-β (P<0.05 or P<0.01). Compared with the TGF-β group, NF-κ B p65 levels in the DHZCP group were decreased (P<0.05). p38 MAPK and NF-κ B p65 levels in the DHZCP+PDTC were also reduced (P<0.01). Compared with the TGF-β group, the protein expression of Smad2 showed a downward trend in the DHZCP, DHZCP+PDTC, and PDTC groups (all P<0.01), and the decreasing trend of Samd3 was statistically significant only in DHZCP+PDTC group (P<0.01), whereas Smad7 was increased (P<0.05 or P<0.01)., Conclusion: DHZCP can inhibit the process of HSC-T6 cell fibrosis by down-regulating the expression of p38 MAPK/NF-κ B/TGF-β1 pathway., Competing Interests: Conflict of Interest. The authors declare that they have no competing interests., (© 2024. The Chinese Journal of Integrated Traditional and Western Medicine Press and Springer-Verlag GmbH Germany, part of Springer Nature.)

Hepatic stellate cells (HSCs) are a major source of fibrogenic cells and play a central role in liver fibrogenesis. HSC activation depends on metabolic activation, for which it is well established that fatty acid oxidation (FAO) sustains their rapid proliferative rate. Studies have indicated that tanshinones inhibit HSC activation, however, the anti-fibrosis mechanisms of tanshinones are remain unclear. Herein, we reported that cryptotanshinone (CTS), a lipid-soluble ingredient of Salvia miltiorrhiza Bunge, exhibited the strongest inhibitory effects on HSC-LX2 proliferation and activation. CTS could induce lipocyte phenotype in mouse primary HSC and HSC-LX2. Transcriptomic sequencing and qPCR revealed that CTS regulated fatty acid metabolism and inhibited CPT1A and CPT1B expression. Target prediction suggested CTS regulates lipid metabolism by targeting STAT3. Mechanistically, the level of ATP and acetyl-CoA were reduced by the treatment of CTS, indicating that CTS could inhibit the level of FAO. Furthermore, CTS could inhibit the phosphorylation and nuclear translocation of STAT3. Additionally, CPT1A overexpression reversed the efficacy of CTS. Finally, CTS (40 mg/kg/day) attenuated CCl 4 -induced liver fibrosis and inhibited collagen production and HSC activation. Moreover, the results of immunofluorescence showed that α-SMA and p-STAT3 were co-located, and CTS could reduce the levels of p-STAT3 and α-SMA. In summary, CTS alleviated liver fibrosis by inhibiting the p-STAT3/CPT1A-dependent FAO both in vitro and in vivo, making it a potential candidate drug 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 © 2024 Elsevier B.V. All rights reserved.)

The activation of hepatic stellate cells (HSCs) is central to the occurrence and development of liver fibrosis. Our previous studies showed that autophagy promotes HSC activation and ultimately accelerates liver fibrosis. Unc-51-like autophagy activating kinase 1 (ULK1) is an autophagic initiator in mammals, and N 6 -methyladenosine (m 6 A) modification is closely related to autophagy. In this study, we find that the m 6 A demethylase fat mass and obesity-associated protein (FTO), which is the m 6 A methylase with the most significant difference in expression, is upregulated during HSC activation and bile duct ligation (BDL)-induced hepatic fibrosis. Importantly, we identify that FTO overexpression aggravates HSC activation and hepatic fibrosis via autophagy. Mechanistically, compared with other autophagy-related genes, ULK1 is a target of FTO because FTO mainly mediates the m 6 A demethylation of ULK1 and upregulates its expression, thereby enhancing autophagy and the activation of HSCs. Notably, the m 6 A reader YTH domain-containing protein 2 (YTHDC2) decreases ULK1 mRNA level by recognizing the m 6 A binding site and ultimately inhibiting autophagy and HSC activation. Taken together, our findings highlight m 6 A-dependent ULK1 as an essential regulator of HSC autophagy and reveal that ULK1 is a novel potential therapeutic target for hepatic fibrosis treatment.

Apigenin (API) is a natural flavonoid compound with antioxidant, anti fibrotic, anti-inflammatory and other effects, but there is limited research on the effect of API on liver fibrosis. This study aims to explore the effect and potential mechanism of API on liver fibrosis induced by CCl4 in mice. The results indicate that API reduces oxidative stress levels, inhibits hepatic stellate cell (HSC) activation, and exerts anti liver fibrosis effects by regulating the PKM2-HIF-1α pathway. We observed that API alleviated liver tissue pathological damage and collagen deposition in CCl4 induced mouse liver fibrosis model, promoting the recovery of liver function in mice with liver fibrosis. In addition, the API inhibits the transition of Pyruvate kinase isozyme type M2 (PKM2) from dimer to tetramer formation by regulating the EGFR-MEK1/2-ERK1/2 pathway, thereby preventing dimer from entering the nucleus and blocking PKM2-HIF-1α access. This change leads to a decrease in malondialdehyde (MDA) and Catalase (CAT) levels and an increase in glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) levels, as well as total antioxidant capacity (T-AOC) in the liver of liver fibrosis mice. At the same time, API downregulated the expression of α-smooth muscle actin (α-SMA), Vimentin and Desmin in the liver tissue of mice with liver fibrosis, inhibited the activation of HSC, and reduced collagen deposition. These results indicate that API can inhibit HSC activation and alleviate CCl4 induced liver fibrosis by inhibiting the PKM2-HIF-1α pathway and reducing oxidative stress, laying an important foundation for the development and clinical application of API as a novel drug for treating 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 © 2024 Elsevier Inc. All rights reserved.)

Sulfenylation is a reversible oxidative posttranslational modification (PTM) of proteins on cysteine residues. Despite the dissection of various biological functions of cysteine sulfenylation, its roles in hepatic fibrosis remain elusive. Here, we report that EphB2, a receptor tyrosine kinase previously implicated in liver fibrosis, is regulated by cysteine sulfenylation during the fibrotic progression of liver. Specifically, EphB2 is sulfenylated at the residues of Cys636 and Cys862 in activated hepatic stellate cells (HSCs), leading to the elevation of tyrosine kinase activity and protein stability of EphB2 and stronger interactions with focal adhesion kinase for the activation of downstream mitogen-activated protein kinase signaling. The inhibitions of both EphB2 kinase activity and cysteine sulfenylation by idebenone (IDE), a marketed drug with potent antioxidant activity, can markedly suppress the activation of HSCs and ameliorate hepatic injury in two well-recognized mouse models of liver fibrosis. Collectively, this study reveals cysteine sulfenylation as a new type of PTM for EphB2 and sheds a light on the therapeutic potential of IDE for the treatment of liver fibrosis., (© 2024. The Author(s).)

Excessive transforming growth factor β1 (TGF-β1) secreted by activated hepatic stellate cells (aHSCs) aggravates liver fibrosis via over-activation of TGF-β1-mediated signaling pathways in a TGF-β type I receptor (TβRI) dependent manner. TβRI with the C-terminal valine truncated (RIPΔ), as a novel TβRI-mimicking peptide, is an appealing anti-fibrotic candidate by competitive binding of TGF-β1 to block TGF-β1 signal transduction. Platelet-derived growth factor receptor β (PDGFβR) is highly expressed on the surface of aHSCs in liver fibrosis. Herein, we designed a novel RIPΔ variant Z-RIPΔ (PDGFβR-specific affibody Z PDGFβR fused to the N-terminus of RIPΔ) for liver fibrosis therapy, and expect to improve the anti-liver fibrosis efficacy by specifically inhibiting the TGF-β1 activity in aHSCs. Target peptide Z-RIPΔ was prepared in Escherichia coli by SUMO fusion system. Moreover, Z-RIPΔ specifically bound to TGF-β1-activated aHSCs, inhibited cell proliferation and migration, and reduced the expression of fibrosis markers (α-SMA and FN) and TGF-β1 pathway-related effectors (p-Smad2/3 and p-p38) in vitro. Furthermore, Z-RIPΔ specifically targeted the fibrotic liver, alleviated the liver histopathology, mitigated the fibrosis responses, and blocked TGF-β1-mediated Smad and p38 MAPK cascades. More importantly, Z-RIPΔ exhibited a higher fibrotic liver-targeting capacity and stronger anti-fibrotic effects than its parent RIPΔ. Besides, Z-RIPΔ showed no obvious toxicity effects in treating both an in vitro cell model and an in vivo mouse model of liver fibrosis. In conclusion, Z-RIPΔ represents a promising targeted candidate for liver fibrosis therapy., Competing Interests: Declaration of competing interest I would like to declare on behalf of my co-authors that all the authors declare that they have no known competing interests. The manuscript is approved by all authors for publication. All the authors listed have approved the manuscript that is enclosed., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Aims: The study aims to investigate the role and underlying mechanisms of tricetin in regulating hepatic stellate cells (HSCs) activation., Main Methods: We treated human hepatic stellate cells line LX-2 and freshly isolated primary mouse hepatic stellate cells (mHSCs) with tricetin, pharmacological inhibitors and siRNAs, western blot, immunofluorescence, quantitative PCR were used to evaluate the expression of fibrotic markers, autophagy levels and Nrf2 (nuclear factor E2-related factor 2) signaling., Key Findings: Herein, we demonstrated that tricetin strongly attenuated the proliferation, migration, lipid droplets (LDs) loss and fibrotic markers Col 1a1 (type I α 1 collagen) and α-SMA (α-smooth muscle actin) expression in LX-2 cells. Moreover, tricetin time- and dose-dependently provoked autophagic formation in LX-2 cells. Autophagy inhibition by pharmacological intervention or genetic ATG5 (autophagy related 5) silencing facilitated tricetin-induced downregulation of profibrotic markers in LX-2 cells. Additionally, tricetin treatment reduced reactive oxygen species (ROS) accumulation, promoted Nrf2 signaling in LX-2 cells and pretreatment with ROS scavenger NAC partially reversed tricetin-induced autophagy and enhanced tricetin-mediated HSCs inactivation. Nrf2 silencing partially reversed tricetin-mediated inhibition of α-SMA expression. Finally, utilizing primary mouse hepatic stellate cells (mHSCs), we demonstrated that tricetin also induced autophagy activation, repressed TGF-β1-induced LDs loss and fibrotic marker expression and pretreatment with CQ further sensitized these effects., Significance: Our study indicates that tricetin's actions may represent an effective strategy to treat liver fibrosis and help identify novel therapeutic targets, especially in combination with autophagy inhibitors., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The combination of lineage tracing and immunohistochemistry has helped to identify subpopulations and fate of hepatic stellate cells (HSC) in murine liver. HSC are sinusoidal pericytes that act as myofibroblast precursors after liver injury. Single cell RNA sequencing approaches have recently helped to differentiate central and portal HSC. A specific Cre line to lineage trace portal HSC has not yet been described. We used three Cre lines (Lrat-Cre, PDGFRβ-CreER T2 and SMMHC-CreER T2 ) known to label mesenchymal cells including HSC in combination with a tdTomato-expressing reporter. All three Cre lines labeled populations of HSC as well as smooth muscle cells (SMC). Using the SMMHC-CreER T2 , we identified a subtype of HSC in the periportal area of the hepatic lobule (termed zone 1-HSC). We lineage traced tdTomato-expressing zone 1-HSC over 1 year, described fibrotic behavior in two fibrosis models and investigated their possible role during fibrosis. This HSC subtype resides in zone 1 under healthy conditions; however, zonation is disrupted in preclinical models of liver fibrosis (CCl 4 and MASH). Zone 1-HSC do not transform into αSMA-expressing myofibroblasts. Rather, they participate in sinusoidal capillarization. We describe a novel subtype of HSC restricted to zone 1 under physiological conditions and its possible function after liver injury. In contrast to the accepted notion, this HSC subtype does not transform into αSMA-positive myofibroblasts; rather, zone 1-HSC adopt properties of capillary pericytes, thereby participating in sinusoidal capillarization., (© 2024. The Author(s).)

The liver is a complex organ that performs vital functions in the body. Despite its extraordinary regenerative capacity compared to other organs, exposure to chemical, infectious, metabolic and immunologic insults and toxins renders the liver vulnerable to inflammation, degeneration and fibrosis. Abnormal wound healing response mediated by aberrant signaling pathways causes chronic activation of hepatic stellate cells (HSCs) and excessive accumulation of extracellular matrix (ECM), leading to hepatic fibrosis and cirrhosis. Fibrosis plays a key role in liver carcinogenesis. Once thought to be irreversible, recent clinical studies show that hepatic fibrosis can be reversed, even in the advanced stage. Experimental evidence shows that removal of the insult or injury can inactivate HSCs and reduce the inflammatory response, eventually leading to activation of fibrolysis and degradation of ECM. Thus, it is critical to understand the role of gene-environment interactions in the context of liver fibrosis progression and regression in order to identify specific therapeutic targets for optimized treatment to induce fibrosis regression, prevent HCC development and, ultimately, improve the clinical outcome.

Non-alcoholic fatty liver disease (NAFLD) is a clinicopathologic syndrome characterized by excessive fat deposition in hepatocytes and a major cause of end-stage liver disease. Autophagy is a metabolic pathway responsible for degrading cytoplasmic products and damaged organelles, playing a pivotal role in maintaining the homeostasis and functionality of hepatocytes. Recent studies have shown that pharmacological intervention to activate or restore autophagy provides benefits for liver function recovery by promoting the clearance of lipid droplets (LDs) in hepatocytes, decreasing the production of pro-inflammatory factors, and inhibiting activated hepatic stellate cells (HSCs), thus improving liver fibrosis and slowing down the progression of NAFLD. This article summarizes the physiological process of autophagy, elucidates the close relationship between NAFLD and autophagy, and discusses the effects of drugs on autophagy and signaling pathways from the perspectives of hepatocytes, kupffer cells (KCs), and HSCs to provide assistance in the clinical management of NAFLD., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Shen, Yang, Wang, Chen, Chen, Zhang, Xiong and Leng.)

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., (Copyright © 2024 Copyright: © 2024 Journal of Cancer Research and Therapeutics.)

The relevance of aberrant serum IgG N-glycosylation in liver fibrosis has been identified; however, its causal effect remains unclear. Because hepatic stellate cells (HSCs) contribute substantially to liver fibrosis, we investigated whether and through which mechanisms IgG N-glycosylation affects the fibrogenic properties of HSCs. Analysis of serum IgG 1 N-glycome from 151 patients with chronic hepatitis B or liver cirrhosis revealed a positive correlation between Ishak fibrosis grading and IgG 1 with agalactosyl N-glycoforms on the crystallizable fragment (Fc). Fc gamma receptor (FcγR) IIIa was observed in cultured human HSCs and HSCs in human liver tissues, and levels of FcγRIIIa in HSCs correlated with the severity of liver fibrosis. Additionally, agalactosyl IgG treatment caused HSCs to have a fibroblast-like morphology, enhanced migration and invasion capabilities, and enhanced expression of the FcγRIIIa downstream tyrosine-protein kinase SYK. Furthermore, agalactosyl IgG treatment increased fibrogenic factors in HSCs, including transforming growth factor (TGF)-β1, total collagen, platelet-derived growth factor subunit B and its receptors, pro-collagen I-α1, α-smooth muscle actin, and matrix metalloproteinase 9. These effects were more pronounced in HSCs that stably expressed FCGR3A and were reduced in FCGR3A knockout cells. Agalactosyl IgG and TGF-β1 each increased FCGR3A in HSCs. Furthermore, serum TGF-β1 concentrations in patients were positively correlated with agalactosyl IgG 1 levels and liver fibrosis severity, indicating a positive feedback loop involving agalactosyl IgG, HSC-FcγRIIIa, and TGF-β1. In conclusion, agalactosyl IgG promotes fibrogenic characteristics in HSCs through FcγRIIIa. © 2024 The Pathological Society of Great Britain and Ireland., (© 2024 The Pathological Society of Great Britain and Ireland.)

Metabolic dysfunction-associated steatohepatitis (MASH) is characterized by infiltration of monocyte-derived macrophages (MdMs) into the liver; however, the function of these macrophages is largely unknown. We previously demonstrated that a population of MdMs, referred to as hepatic lipid-associated macrophages (LAMs), assemble into aggregates termed hepatic crown-like structures in areas of liver fibrosis. Intriguingly, decreasing MdM recruitment resulted in increased liver fibrosis, suggesting that LAMs contribute to antifibrotic pathways in MASH. In this study, we determined that hepatic crown-like structures are characterized by intimate interactions between activated hepatic stellate cells (HSCs) and macrophages in a collagen matrix in a mouse model of MASH. MASH macrophages displayed collagen-degrading capacities, and HSCs derived from MASH livers promoted expression of LAM marker genes and acquisition of a collagen-degrading phenotype in naive macrophages. These data suggest that crosstalk between HSCs and macrophages may contribute to collagen degradation MASH., (Copyright © 2024 by The American Association of Immunologists, Inc.)

Liver fibrosis, a progressive process of fibrous scarring, results from the accumulation of extracellular matrix proteins (ECM). If left untreated, it often progresses to diseases such as cirrhosis and hepatocellular carcinoma. Lycorine, a natural alkaloid derived from medicinal plants, has shown diverse bioactivities by targeting JAK2/STAT3 signaling, but its pharmacological effects and potential molecular mechanisms in liver fibrosis remains largely unexplored. The purpose of this study is to elucidate the pharmacological activity and molecular mechanism of lycorine in anti-hepatic fibrosis. Findings indicate that lycorine significantly inhibited hepatic stellate cells (HSCs) activation by reducing the expression of α-SMA and collagen-1. In vivo, lycorine treatment alleviated carbon tetrachloride (CCl 4 ) -induced mice liver fibrosis, improving liver function, decreasing ECM deposition, and inhibiting fibrosis-related markers' expression. Mechanistically, it was found that lycorine exerts protective activity through the JAK2/STAT3 and PI3K/AKT signaling pathways, as evidenced by transcriptome sequencing technology and small molecule inhibitors. These results underscore lycorine's potential as a therapeutic drug for 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 © 2024 Elsevier Inc. All rights reserved.)

Hepatic fibrosis is the basis of multiple liver diseases and may eventually develop into hepatocellular carcinoma. Hepatic stellate cell (HSC) activation is a driving factor of hepatic fibrogenesis. In the liver microenvironment, liver cells and others play a crucial role in HSC activation. The liver tissues of CCl4-induced rats show excessive fibrosis, inflammation, and cell apoptosis. Yin Yang 1 (YY1) was highly expressed in hepatic fibrosis rats and TGF-β1-treated liver cells. In animal experiments, YY1 knockdown effectively attenuated CCl 4 -induced liver injury and pyroptosis-related IL-1β and IL-18 expression. In cellular experiments, NLRP3 inflammasome-mediated pyroptosis was activated by TGF-β1 treatment, while YY1 knockdown significantly inhibited the activation of the NLRP3 inflammasome, pyroptosis, and the secretion of IL-1β and IL-18. In addition, our data showed that TGF-β1-treated liver cell conditional medium markedly induced HSC activation, which was rescued by YY1 knockdown in liver cells. YY1 overexpression in liver cells contributed to the activation of TGF-β1-treated liver cell conditional medium in HSCs, however, this effect of YY1 was attenuated by NLRP3 inhibition. Overall, YY1 overexpression in liver cells contributed to HSC activation by facilitating IL-1β and IL-18 production via activating NLRP3 inflammasome-mediated pyroptosis, thus aggravating hepatic fibrogenesis. Our data indicate that YY1 may be a novel target for the treatment of hepatic fibrosis and associated liver diseases., (©The Author(s) 2024. Open Access. This article is licensed under a Creative Commons CC-BY International License.)

Background and Aim: Hydronidone (HDD) is a novel pirfenidone derivative developed initially to reduce hepatotoxicity. Our previous studies in animals and humans have demonstrated that HDD treatment effectively attenuates liver fibrosis, yet the underlying mechanism remains unclear. This study aimed to investigate whether HDD exerts its anti-fibrotic effect by inducing apoptosis in activated hepatic stellate cells (aHSCs) through the endoplasmic reticulum stress (ERS)-associated mitochondrial apoptotic pathway., Methods: The carbon tetrachloride (CCl 4 )- and 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced liver fibrosis models were used for in vivo studies. In vitro studies were conducted using the human hepatic stellate cell line LX-2. The apoptotic effect of HDD on aHSCs was examined using TUNEL and flow cytometry assays. The small interfering RNA (siRNA) technique was employed to downregulate the expression of interest genes., Results: HDD treatment significantly promoted apoptosis in aHSCs in both the CCl 4 - and DDC-induced liver fibrosis in mice and LX-2 cells. Mechanistic studies revealed that HDD triggered ERS and subsequently activated the IRE1α-ASK1-JNK pathway. Furthermore, the influx of cytochrome c from the mitochondria into the cytoplasm was increased, leading to mitochondrial dysfunction and ultimately triggering apoptosis in aHSCs. Notably, inhibition of IRE1α or ASK1 by siRNA partially abrogated the pro-apoptotic effect of HDD in aHSCs., Conclusions: The findings of both in vivo and in vitro studies suggest that HDD induces apoptosis in aHSCs via the ERS-associated mitochondrial apoptotic pathway, potentially contributing to the amelioration of liver fibrosis., (© 2024 The Author(s). Journal of Gastroenterology and Hepatology published by Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

Background: Non-alcoholic steatohepatitis (NASH) and liver fibrosis are progressive conditions associated with non-alcoholic fatty liver disease (NAFLD), characterized by hepatocyte pyroptosis and hepatic stellate cell (HSC) activation. Gentiopicroside (GPS) has emerged as a potential treatment for NASH, yet its underlying mechanism remains unclear., Aim: To confirm that GPS can improve NASH and liver fibrosis by blocking the NLRP3 signaling pathway STUDY DESIGN: Initially, different animal models were used to study the effects and mechanisms of GPS on NASH and fibrosis. Subsequent in vitro experiments utilized co-cultures and other techniques to delve deeper into its mechanism, followed by validation of the findings in mouse liver tissues., Methods: C57BL/6 mice were fed high-fat, high-cholesterol (HFHC), or methionine-choline-deficient (MCD) diets to induce NASH and fibrosis. RAW264.7 cells and born marrow bone marrow-derived macrophages (BMDMs) were stimulated with LPS and ATP to induce inflammation, then co-cultured with primary hepatocytes and HSCs, treated with GPS, and its efficacy and mechanism were analyzed., Results: In vivo, GPS alleviated NASH and liver fibrosis by inhibiting the NLRP3 pathway. In vitro, GPS attenuated inflammation induced by BMDMs by inhibiting TLR4 and NLRP3 signaling pathways, and Co-culture studies suggested that GPS reduced hepatocyte pyroptosis and HSC activation, which was also confirmed in liver tissues CONCLUSION: GPS improves NASH and liver fibrosis by inhibiting the TLR4 and NLRP3 signaling pathways. The specific mechanism may be related to the suppression of macrophage-mediated inflammatory responses, thereby reducing hepatocyte pyroptosis and HSC 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 © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Liver fibrosis is a condition characterized by aberrant proliferation of connective tissue in the liver resulting from diverse etiological factors. G protein-coupled receptor GPR55 has recently been identified as a regulator of liver diseases. Herein, we report the discovery of a cyclic peptide P1-1 that antagonizes GPR55 and suppresses collagen secretion in hepatic stellate cells. The alanine scanning and docking study was carried out to predict the binding mode and allowed for further structural optimization of peptide antagonists for GPR55. The subsequent in vivo study demonstrated that P1-1 ameliorates CCl 4 -induce and MCD-diet-induce acute liver inflammation and fibrosis. Further study indicates that P1-1 reduces reactive oxygen species (ROS) production, attenuates ER stress, and inhibits mitochondria-associated hepatocyte apoptosis. In this work, we provided the first successful example of antagonizing GPR55 for liver inflammation and fibrosis, which validates GPR55 as a promising target for the treatment of liver fibrosis and affords a high-potent GPR55 antagonist P1-1 as a potential therapeutic candidate.

The burden of chronic liver disease is globally increasing at an alarming rate. Chronic liver injury leads to liver inflammation and fibrosis (LF) as critical determinants of long-term outcomes such as cirrhosis, liver cancer, and mortality. LF is a wound-healing process characterized by excessive deposition of extracellular matrix (ECM) proteins due to the activation of hepatic stellate cells (HSCs). In the healthy liver, quiescent HSCs metabolize and store retinoids. Upon fibrogenic activation, quiescent HSCs transdifferentiate into myofibroblasts; lose their vitamin A; upregulate α-smooth muscle actin; and produce proinflammatory soluble mediators, collagens, and inhibitors of ECM degradation. Activated HSCs are the main effector cells during hepatic fibrogenesis. In addition, the accumulation and activation of profibrogenic macrophages in response to hepatocyte death play a critical role in the initiation of HSC activation and survival. The main source of myofibroblasts is resident HSCs. Activated HSCs migrate to the site of active fibrogenesis to initiate the formation of a fibrous scar. Single-cell technologies revealed that quiescent HSCs are highly homogenous, while activated HSCs/myofibroblasts are much more heterogeneous. The complex process of inflammation results from the response of various hepatic cells to hepatocellular death and inflammatory signals related to intrahepatic injury pathways or extrahepatic mediators. Inflammatory processes modulate fibrogenesis by activating HSCs and, in turn, drive immune mechanisms via cytokines and chemokines. Increasing evidence also suggests that cellular stress responses contribute to fibrogenesis. Recent data demonstrated that LF can revert even at advanced stages of cirrhosis if the underlying cause is eliminated, which inhibits the inflammatory and profibrogenic cells. However, despite numerous clinical studies on plausible drug candidates, an approved antifibrotic therapy still remains elusive. This state-of-the-art review presents cellular and molecular mechanisms involved in hepatic fibrogenesis and its resolution, as well as comprehensively discusses the drivers linking liver injury to chronic liver inflammation and LF.

Liver fibrosis is a significant health concern globally due to its association with severe liver conditions like cirrhosis and liver cancer. Histone lactylation has been implicated in the progression of hepatic fibrosis, but its specific role in liver fibrosis, particularly regarding H3K18 lactylation, remained unclear. To investigate this, we established in vivo and in vitro models of liver fibrosis using carbon tetrachloride (CCl4) injection in rats and stimulation of hepatic stellate cells (HSCs) with TGF-β1, respectively. We found that histone lactylation, particularly H3K18 lactylation, was upregulated in both CCl4-induced rats and TGF-β1-activated HSCs, indicating its potential involvement in liver fibrosis. Further experiments revealed that lactate dehydrogenase A (LDHA) knockdown inhibited H3K18 lactylation and had a beneficial effect on liver fibrosis by suppressing HSC proliferation, migration, and extracellular matrix (ECM) deposition. This suggests that H3K18 lactylation promotes liver fibrosis progression. Chromatin immunoprecipitation (ChIP) and luciferase reporter assays demonstrated that H3K18 lactylation facilitated the transcription of SOX9, a transcription factor associated with fibrosis. Importantly, overexpression of SOX9 counteracted the effects of LDHA silencing on activated HSCs, indicating that SOX9 is downstream of H3K18 lactylation in promoting liver fibrosis. In summary, this study uncovers a novel mechanism by which H3K18 lactylation contributes to liver fibrosis by activating SOX9 transcription. This finding opens avenues for exploring new therapeutic strategies for hepatic fibrosis targeting histone lactylation pathways., 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 © 2024 Elsevier Inc. All rights reserved.)

Hepatic stellate cells (HSCs) activation is a key event in the development of liver fibrosis, and blockage of the activation of HSCs has been shown to alleviate liver fibrosis. Sophoridine, a bioactive alkaloid found in many Chinese herbs, exhibits a broad spectrum of pharmacological effects, but its activities are not strong. In this study, a series of structurally modified derivatives of sophoridine were designed and synthesized. Among them, sophoridine α-aryl propionamide derivative ZM600 displayed a significant inhibitory effect on the activation of HSCs. The in vivo experiment demonstrated that ZM600 markedly ameliorated carbon tetrachloride (CCl 4 ) and bile duct ligation (BDL)-induced liver fibrosis with a significant improvement of extracellular matrix deposition. Mechanism investigations revealed that ZM600 specifically inhibited the activation of NF-κB, PI-3K/AKT, and TGF-β/Smads signaling pathways. These results suggest that ZM600 has a protective effect on liver fibrosis, which provides a new candidate for the treatment of liver fibrosis.