Mechanisms of hepatic fibrogenesis

The SLIT/ROBO Pathway in Liver Fibrosis and Cancer

Liver fibrosis is a common outcome of most chronic liver insults/injuries that can develop into an irreversible process of cirrhosis and, eventually, liver cancer. In recent years, there has been significant progress in basic and clinical research on liver cancer, leading to the identification of various signaling pathways involved in tumorigenesis and disease progression. Slit glycoprotein (SLIT)1, SLIT2, and SLIT3 are secreted members of a protein family that accelerate positional interactions between cells and their environment during development. These proteins signal through Roundabout receptor (ROBO) receptors (ROBO1, ROBO2, ROBO3, and ROBO4) to achieve their cellular effects. The SLIT and ROBO signaling pathway acts as a neural targeting factor regulating axon guidance, neuronal migration, and axonal remnants in the nervous system. Recent findings suggest that various tumor cells differ in SLIT/ROBO signaling levels and show varying degrees of expression patterns during tumor angiogenesis, cell invasion, metastasis, and infiltration. Emerging roles of the SLIT and ROBO axon-guidance molecules have been discovered in liver fibrosis and cancer development. Herein, we examined the expression patterns of SLIT and ROBO proteins in normal adult livers and two types of liver cancers: hepatocellular carcinoma and cholangiocarcinoma. This review also summarizes the potential therapeutics of this pathway for anti-fibrosis and anti-cancer drug development.

Euryachincoside, a Novel Phenolic Glycoside with Anti-Hepatic Fibrosis Activity from Eurya chinensis

Eurya chinensis has been recorded as a folk medicine traditionally used for treatment of a variety of symptoms. However, the phytochemical and pharmacological investigations of this plant are still scarce. A novel phenolic glycoside named Euryachincoside (ECS) was isolated by chromatographic separation from E. chinensis, and its chemical structure was identified by analysis of HRMS and NMR data. Its anti-hepatic fibrosis effects were evaluated in both HSC-T6 (rat hepatic stellate cells) and carbon tetrachloride (CCl₄)-induced mice with Silybin (SLB) as the positive control. In an in vitro study, ECS showed little cytotoxicity and inhibited transforming growth factor-beta (TGF-β)-induced Collagen I (Col1) along with alpha-smooth muscle actin (α-SMA) expressions in HSC-T6. An in vivo study suggested ECS significantly ameliorated hepatic injury, secretions of inflammatory cytokines, and collagen depositions. Moreover, ECS markedly mediated Smad2/3, nuclear factor kappa B (NF-κB) and nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathways both in vitro and vivo. These present findings confirmed that ECS is a novel phenolic glycoside from E. chinensis with promising curative effects on hepatic fibrosis, and its mechanisms may include decreasing extracellular matrix accumulation, reducing inflammation and attenuating free radicals via Smad2/3, NF-κB and Nrf2 signaling pathways, which may shed light on the exploration of more effective phenolic glycoside-based anti-fibrotic agents.

Role and mechanism of DNA methylation and its inhibitors in hepatic fibrosis

Liver fibrosis is a repair response to injury caused by various chronic stimuli that continually act on the liver. Among them, the activation of hepatic stellate cells (HSCs) and their transformation into a myofibroblast phenotype is a key event leading to liver fibrosis, however the mechanism has not yet been elucidated. The molecular basis of HSC activation involves changes in the regulation of gene expression without changes in the genome sequence, namely, via epigenetic regulation. DNA methylation is a key focus of epigenetic research, as it affects the expression of fibrosis-related, metabolism-related, and tumor suppressor genes. Increasing studies have shown that DNA methylation is closely related to several physiological and pathological processes including HSC activation and liver fibrosis. This review aimed to discuss the mechanism of DNA methylation in the pathogenesis of liver fibrosis, explore DNA methylation inhibitors as potential therapies for liver fibrosis, and provide new insights on the prevention and clinical treatment of liver fibrosis.

Chinese Herbal Formula Ruangan Granule Enhances the Efficacy of Entecavir to Reverse Advanced Liver Fibrosis/Early Cirrhosis in Patients with Chronic HBV Infection: A Multicenter, Randomized Clinical Trial

BACKGROUND

Nucleotide analogs treatment can reverse liver fibrosis in chronic hepatitis B (CHB). However, it has limited effect on fibrosis resolution in patients with CHB, particularly in preventing progression to hepatocellular carcinoma (HCC). Ruangan granule (RG), a Chinese herbal formula, has proven to produce a therapeutic effect against liver fibrosis in animal experiment. Thus, we aimed to evaluate the effect of our Chinese herbal formula (RG) combined with entecavir (ETV) to reverse advanced liver fibrosis/early cirrhosis from CHB.

METHODS

A total of 240 CHB patients with histologically confirmed advanced liver fibrosis/early cirrhosis from 12 centers were randomly and blindly allocated to consume either ETV (0.5mg/day) plus RG (2 times/day) or control (ETV) for 48 weeks (wk) treatment. Changes in histopathology, serology and imageology were observed. Liver fibrosis reversion, defined as a reduction in the Knodell HAI score by ≥2 points and Ishak score by ≥1 grade, was assessed.

RESULTS

The rate of fibrosis regression and inflammation remission after 48 wk of treatment in histopathology was significantly higher in the ETV + RG group (38.73% vs. 23.94%, P=0.031). The ultrasonic semiquantitative scores decreased by ≥2 points and were 41 (28.87%) and 15 (21.13%) in the ETV+RG and ETV groups, respectively (P=0.026). The ETV+RG group had a significantly lower Fibrosis-4 score (FIB-4) index (P=0.028). There was a significant difference between the ETV+RG and ETV groups in the liver function normalization rate (P <0.01). Moreover, ETV plus RG combination treatment further reduced the risk of HCC in median 55-month follow-up (P <0.01).

CONCLUSIONS

This study illustrates that the Chinese herbal formula RG with ETV can improve advanced liver fibrosis/early cirrhosis regression in patients with CHB, further reducing the risk of HCC.

Research and progress of inflammasomes in nonalcoholic fatty liver disease

With the development of the social economy, unhealthy living habits and eating styles are gradually affecting people's health in recent years. As a chronic liver disease, NAFLD is deeply affected by unhealthy living habits and eating styles and has gradually become an increasingly serious public health problem. As a protein complex in clinical research, the inflammasomes play a crucial role in the development of NAFLD, atherosclerosis, and other diseases. This paper reviews the types, composition, characteristics of inflammasomes, and molecular mechanism of the inflammasome in NAFLD. Meanwhile, the paper reviews the drugs and non-drugs that target NLRP3 inflammasome in the treatment of NAFLD in the past decades. we also analyzed and summarized the related experimental models, mechanisms, and results of NAFLD. Although current therapeutic strategies for NAFLD are not effective, we expect that we will be able to find an appropriate treatment to address this problem in the future with further research on inflammasome.

SNAI1-activated long non-coding RNA LINC01711 promotes hepatic fibrosis cell proliferation and migration by regulating XYLT1

Liver fibrosis is the result of the accumulation of extracellular matrix (ECM) that cannot be cleared. Bioinformatic analysis showed that LINC01711 was significantly overexpressed in hepatic fibrosis. The regulatory mechanism of LINC01711 was clarified and confirmed the transcription factors associated with LINC01711. Functionally, LINC01711 promoted LX-2 cell proliferation and migration, indicating that it exerts effects promoting the progression of hepatic fibrosis. Mechanistically, LINC01711 increased the expression of xylosyltransferase 1 (XYLT1), which is an important protein for constructing the ECM. We also confirmed that SNAI1 activated LINC01711 transcription. Taking these findings together, LINC01711 was induced by SNAI1 and promoted the proliferation and migration of LX-2 cells via XYLT1. This study will help to understand the function of LINC01711 and its regulatory mechanism in hepatic fibrosis.

Flavonoid constituents and protective efficacy of Citrus reticulate (Blanco) leaves ethanolic extract on thioacetamide-induced liver injury rats

Context: Oxidative stress leads to deleterious processes in the liver that resulted in liver diseases.Objective: To evaluate antioxidant activity and hepatoprotective potential of ethanolic leaves extract of Citrus reticulate against hepatic dysfunction induced by thioacetamide (TAA).Materials and Methods: Flavonoid constituents were isolated from the ethanol extract by chromatographic techniques and identified by the spectroscopic analyses. Antioxidant activity was determined using DPPH assay. Hepatotoxicity was induced in rats via intraperitoneal injection of TAA and the ethanol extract was orally administrated at a dose of 100 mg/kg/day for four weeks. Serum biomarkers, hepatic antioxidant enzymes, tumour necrosis factor-alpha (TNF-α), hepatic hydroxyproline levels, and histopathology were examined.Results: Ten known flavonoids were identified, among of them, 6,3`-dimethoxyluteolin and 8,3`-dimethoxyluteolin possessed the highest antioxidant activity. The substantially elevated serum enzymatic levels of ALT, ALP, and bilirubin were found to be restored towards normalisation significantly by the plant extract. Furthermore, the markers including MDA, GSH, SOD, NO, and protein carbonyl which were close to oxidative damage, were restored. Meanwhile, the extract treatment decreased TNF-α level and also was able to reverse the induced fibrosis by significantly reducing the hydroxyproline content. Moreover, histopathological studies further substantiate the protective effect of the extract.Conclusion: C. reticulate leaves extract is a rich source of phytochemicals with in vitro and in vivo protective effects.

Hepatocyte Ninjurin2 promotes hepatic stellate cell activation and liver fibrosis through the IGF1R/EGR1/PDGF-BB signaling pathway

BACKGROUND

Liver fibrogenesis is orchestrated by the paracrine signaling interaction between several resident cell types regulating the activation of hepatic stellate cells (HSCs). However, the molecular mechanisms underlying paracrine regulation are largely unknown. The aim of this study is to elucidate the role of Ninjurin2 in the crosstalk between hepatocytes and HSCs and better understand the implications of Ninjurin2 in liver fibrosis.

METHODS

Ninj2 knockout mice (Ninj2^-/-) and hepatocyte-specific Ninj2 overexpression mice (Ninj2^Hep-tg) were constructed and followed by the induction of liver fibrosis using methionine- and choline-deficient (MCD) diet. The relationship between Ninjurin2 and liver fibrosis phenotype was evaluated in vivo by measurement of fibrotic markers and related genes. We used an in vitro transwell cell co-culture model to examine the impact of Ninjurin2 in hepatocytes on the crosstalk to HSCs. The interaction of Ninjurin2 and IGF1R and the regulation of PI3K-AKT-EGR1 were analyzed in vivo and in vitro. Finally, an inhibitory Ninjurin2 peptide was injected intravenously via the tail vein to investigate whether inhibiting of Ninjurin2 cascade can attenuate MCD diet-induced liver fibrosis in mice.

RESULTS

We found that hepatic Ninjurin2 expression was significantly increased in fibrotic human liver and MCD diet-induced liver injury mouse models. In the mouse model, hepatocyte-specific overexpression of Ninj2 exacerbates MCD-induced liver fibrosis, while global Ninj2 knockout reverses the phenotype. To mimic hepatocyte-HSC crosstalk during liver fibrosis, we used co-culture systems containing hepatocytes and HSCs and determined that Ninjurin2 overexpression in hepatocytes directly activates HSCs in vitro. Mechanistically, Ninjurin2 directly interacts with insulin-like growth factor 1 receptor (IGF1R) and increases the hepatocyte secretion of the fibrogenic cytokine, platelet-derived growth factor-BB (PDGF-BB) through IGF1R-PI3K-AKT-EGR1 cascade. Inhibition of PDGFRB signaling in HSCs can abolish the profibrogenic effect of Ninjurin2. In addition, we demonstrated that a specific inhibitory Ninjurin2 peptide containing an N-terminal adhesion motif mitigates liver fibrosis and improves hepatic function in the mouse models by negatively regulating the sensitivity of IGF1R to IGF1 in hepatocytes.

CONCLUSION

Hepatic Ninjurin2 plays a key role in liver fibrosis through paracrine regulation of PDGF-BB/PDGFRB signaling in HSCs, and the results suggesting Ninjurin2 may be a potential therapeutic target.

Moquiniastrum polymorphum subsp. polymorphum extract inhibits the proliferation of an activated hepatic stellate cell line (GRX) by regulating the p27 pathway to generate cell cycle arrest

ETHNOPHARMACOLOGICAL RELEVANCE

The chosen plant and its extracts have been an alternative in the treatment of several inflammatory and oxidant diseases, and is therefore a viable option for the treatment of hepatic fibrosis.

AIM OF THE STUDY

This study aimed to use Moquiniastrum polymorphum subsp. polymorphum, mainly the ethanolic extract and fractions, in the treatment of hepatic fibrosis.

MATERIALS AND METHODS

Extracts were prepared from dried leaves in 100% ethanol (ET) and fractionated with an increased polarity solvent (dichloromethane to methanol). The quantification of compounds in the extracts was characterized by GCMS. The decrease in cell proliferation and the cytotoxicity of the extracts were evaluated together with the mechanisms of apoptosis and autophagy. The expression of genes associated with decreased fibrosis and cell cycle control was assessed and the production of lipid droplets was quantified by Oil Red O staining.

RESULTS

The experiments showed that treatment with ET and fraction 1 (F1) inhibited the expression of CDKIs (CCDN1, CDK2, CDK4 and CDK6) through an increase in p27, related to an increase in autophagic vesicles. The extract and F1 were able to decrease proliferation and revert the activated state of GRX cells to their quiescent state.

CONCLUSION

Our results suggest that extracts obtained from Moquiniastrum polymorphum subsp. polymorphum have a potential therapeutic effect against liver fibrosis.

A standardized pomegranate fruit extract ameliorates thioacetamide-induced liver fibrosis in rats via AGE-RAGE-ROS signaling

This work aimed to investigate a possible mechanism that may mediate the hepatoprotective effects of pomegranate fruit extract (PFE) against thioacetamide (THIO)-induced liver fibrosis in rats. Male Sprague Dawley rats were randomly allocated into four groups (n = 8 each): control; PFE (150 mg/kg/day, orally); THIO (200 mg/kg, i.p, 3 times a week); and THIO and PFE-treated groups. Oral PFE treatment decreased liver/body weight ratio by 12.4%, diminished serum function levels of ALT, AST, ALP, LDH, and total bilirubin, increased serum albumin, boosted hepatic GSH (by 35.6%) and SOD (by 17.5%), and significantly reduced hepatic levels of ROS, MDA, 4-HNE, AGEs, and RAGE in THIO-fibrotic rats relative to untreated THIO group. Moreover, PFE administration downregulated the hepatic levels of profibrotic TGF-β1 (by 23.0%, P < 0.001) and TIMP-1 (by 41.5%, P < 0.001), attenuated α-SMA protein expression, decreased serum HA levels (by 41.3%), and reduced the hepatic levels of the fibrosis markers hydroxyproline (by 26.0%, P < 0.001), collagen type IV (by 44.3%, P < 0.001) and laminin (by 43.4%, P < 0.001) compared to the untreated THIO group. The histopathological examination has corroborated these findings, where PFE decreased hepatic nodule incidence, attenuated portal necroinflammation and reduced extent of fibrosis. These findings may suggest that oral PFE administration could slow the progression of hepatic fibrogenesis via reducing hepatic levels of AGEs, RAGE, ROS, TGF-β1, and TIMP-1.

Lipocalin-2 activates hepatic stellate cells and promotes nonalcoholic steatohepatitis in high-fat diet-fed Ob/Ob mice

BACKGROUND AND AIMS

In obesity and type 2 diabetes mellitus, leptin promotes insulin resistance and contributes to the progression of NASH via activation of hepatic stellate cells (HSCs). However, the pathogenic mechanisms that trigger HSC activation in leptin-deficient obesity are still unknown. This study aimed to determine how HSC-targeting lipocalin-2 (LCN2) mediates the transition from simple steatosis to NASH.

APPROACH AND RESULTS

Male wild-type (WT) and ob/ob mice were fed a high-fat diet (HFD) for 20 weeks to establish an animal model of NASH with fibrosis. Ob/ob mice were subject to caloric restriction or recombinant leptin treatment. Double knockout (DKO) mice lacking both leptin and lcn2 were also fed an HFD for 20 weeks. In addition, HFD-fed ob/ob mice were treated with gadolinium trichloride to deplete Kupffer cells. The LX-2 human HSCs and primary HSCs from ob/ob mice were used to investigate the effects of LCN2 on HSC activation. Serum and hepatic LCN2 expression levels were prominently increased in HFD-fed ob/ob mice compared with normal diet-fed ob/ob mice or HFD-fed WT mice, and these changes were closely linked to liver fibrosis and increased hepatic α-SMA/matrix metalloproteinase 9 (MMP9)/signal transducer and activator of transcription 3 (STAT3) protein levels. HFD-fed DKO mice showed a marked reduction of α-SMA protein compared with HFD-fed ob/ob mice. In particular, the colocalization of LCN2 and α-SMA was increased in HSCs from HFD-fed ob/ob mice. In primary HSCs from ob/ob mice, exogenous LCN2 treatment induced HSC activation and MMP9 secretion. By contrast, LCN2 receptor 24p3R deficiency or a STAT3 inhibitor reduced the activation and migration of primary HSCs.

CONCLUSIONS

LCN2 acts as a key mediator of HSC activation in leptin-deficient obesity via α-SMA/MMP9/STAT3 signaling, thereby exacerbating NASH.

Research progress of metformin in the treatment of liver fibrosis

Liver fibrosis is a disease with significant morbidity and mortality. It is a chronic pathological process characterized by an imbalance of extracellular matrix production and degradation in liver tissue. Metformin is a type of hypoglycemic biguanide drug, which can be used in the treatment of liver fibrosis, but its anti-fibrotic effect and mechanism of action are unclear. The purpose of this article is to review the research progress of metformin in the treatment of liver fibrosis and to provide a theoretical basis for its application in the treatment of liver fibrosis.

Upregulation of GLT25D1 in Hepatic Stellate Cells Promotes Liver Fibrosis via the TGF-β1/SMAD3 Pathway In Vivo and In vitro

BACKGROUND AND AIMS

Collagen β(1-O) galactosyltransferase 25 domain 1 (GLT25D1) is associated with collagen production and glycosylation, and its knockout in mice results in embryonic death. However, its role in liver fibrosis remains elusive, particularly in hepatic stellate cells (HSCs), the primary collagen-producing cells associated with liver fibrogenesis. Herein, we aimed to elucidate the role of GLT25D1 in HSCs.

METHODS

Bile duct ligation (BDL)-induced mouse liver fibrosis models, primary mouse HSCs (mHSCs), and transforming growth factor beta 1 (TGF-β1)-stimulated LX-2 human hepatic stellate cells were used in in vivo and in vitro studies. Stable LX-2 cell lines with either GLT25D1 overexpression or knockdown were established using lentiviral transfection. RNA-seq was performed to investigate the genomic differences. HPLC-MS/MS were used to identify glycosylation sites. Scanning electronic microscopy (SEM) and second-harmonic generation/two-photon excited fluorescence (SHG/TPEF) were used to image collagen fibril morphology.

RESULTS

GLT25D1 expression was upregulated in nonparenchymal cells in human cirrhotic liver tissues. Meanwhile, its knockdown attenuated collagen deposition in BDL-induced mouse liver fibrosis and inhibited mHSC activation. GLT25D1 was overexpressed in activated versus quiescence LX-2 cells and regulated in vitro LX-2 cell activation, including proliferation, contraction, and migration. GLT25D1 also significantly increased liver fibrogenic gene and protein expression. GLT25D1 upregulation promoted HSC activation and enhanced collagen expression through the TGF-β1/SMAD signaling pathway. Mass spectrometry showed that GLT25D1 regulated the glycosylation of collagen in HSCs, affecting the diameter of collagen fibers.

CONCLUSIONS

Collectively, the upregulation of GLT25D1 in HSCs promoted the progression of liver fibrosis by affecting HSCs activation and collagen stability.

Protective role of resveratrol against VCM-induced hepatotoxicity in male wistar rats

Background: Vancomycin is a glycopeptide antibiotic with a high risk of acute liver injury. Resveratrol is believed to protect the liver against toxicity. Aim: To investigate the ability of resveratrol to attenuate vancomycin-induced liver toxicity in rats injected with vancomycin. Method: Twenty-four adult male Wistar rats were distributed into three groups. The control group received only a vehicle, while the treated group received either vancomycin 200 (mg/kg, i. p.) only or vancomycin (200 mg/kg, i. p.) with resveratrol (20 mg/kg, oral gavage). All groups received their dose once daily for 7 days. Hepatic damage was assessed by measuring biochemical parameter levels in serum, aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH). Also, antioxidants and inflammation biomarkers such as Interleukin-6 (IL-6), malondialdehyde (MDA), nitric oxide (NO), and glutathione (GSH) were measured. Furthermore, the vancomycin-induced pathological changes in the liver were evaluated by histopathological studies. Results: In the vancomycin-treated group, hepatic serum biomarkers such as AST, ALT, ALP, IL-6, and MDA were elevated, while NO and GSH were depleted. However, resveratrol co-treatment with vancomycin prevented the elevation of AST, ALT, ALP, IL-6, and MDA and it protected the liver from NO and GSH depletion. Also, regarding vancomycin-induced degeneration of hepatocytes, resveratrol co-treatment with vancomycin prevented such degeneration and improved mononuclear cells in the liver. Conclusion: The results showed that oral administration of resveratrol has a significant hepatoprotective effect against vancomycin-induced hepatotoxicity.

Biochanin A in murine Schistosoma mansoni infection: effects on inflammation, oxidative stress and fibrosis

Biochanin A (BCA) is a multifunctional natural compound that possesses anti-infective, anti-inflammatory, anti-oxidative and hepatoprotective effects. The aim of the study was to assess the therapeutic efficacy of BCA on Schistosoma mansoni-infected mice. Fifty mice were divided into six different groups as non-infected, non-infected BCA-treated, infected untreated, early infected BCA-treated (seven days post-infection (dpi)), late infected BCA-treated 60 dpi and infected praziquantel (PZQ)-treated groups. Parasitological, histopathological examination and immunohistochemical staining of transforming growth factor (TGF)-β, inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX-2) were investigated in liver sections. Cytochrome P450 (CYP450) gene expression of S. mansoni was evaluated by quantitative real-time polymerase chain reaction (RT-qPCR). A single dose of BCA significantly reduced worm burden in early (82.14%) and late infection (77.74%), mean tissue egg load in early (7.27 ± 0.495) and late BCA administration (7.63 ± 0.435) and decreased granuloma size. CYP450 mRNA expression was significantly reduced in early BCA treatment as compared to late treatment which emphasizes that early administration of BCA had more pronounced effects on worms than late administration. Both early and late BCA administration led to significant reduction in inflammatory cytokines as TGF and iNOS. Although the reduction of TGF and iNOS in BCA-treated mice was superior to PZQ, no statistically significant differences were noted. However, a significant downregulation of COX2 was noted in hepatocytes as compared to both infected control and PZQ-treated mice. BCA has schistosomicidal, anti-inflammatory, antioxidant and anti-fibrotic effects and could be regarded as a potential drug in schistosomiasis treatment.

Busting the myth of methotrexate chronic hepatotoxicity

Methotrexate is a key component of the treatment of inflammatory rheumatic diseases and the mainstay of therapy in rheumatoid arthritis. Hepatotoxicity has long been a concern for prescribers envisaging long-term treatment with methotrexate for their patients. However, the putative liver toxicity of methotrexate should be evaluated in the context of advances in our knowledge of the pathogenesis and natural history of liver disease, especially non-alcoholic fatty liver disease (NAFLD). Notably, patients with NAFLD are at increased risk for methotrexate hepatotoxicity, and methotrexate can worsen the course of NAFLD. Understanding the mechanisms of acute hepatotoxicity can facilitate the interpretation of elevated concentrations of liver enzymes in this context. Liver fibrosis and the mechanisms of fibrogenesis also need to be considered in relation to chronic exposure to methotrexate. A number of non-invasive tests for liver fibrosis are available for use in patients with rheumatic disease, in addition to liver biopsy, which can be appropriate for particular individuals. On the basis of the available evidence, practical suggestions for pretreatment screening and long-term monitoring of methotrexate therapy can be made for patients who have (or are at risk for) chronic liver disease.

The non-selective Rho-kinase inhibitors Y-27632 and Y-33075 decrease contraction but increase migration in murine and human hepatic stellate cells

BACKGROUND

The Rho-kinase ROCK II plays a major role in the activation of hepatic stellate cells (HSC), which are the key profibrotic and contractile cells contributing to the development of chronic liver disease. Inhibition of ROCK II ultimately blocks the phosphorylation of the myosin light chain (MLC) and thus inhibits stress fibre assembly and cell contraction. We investigated the effects of the ROCK inhibitors Y-33075 as well as Y-27632 in murine and human hepatic stellate cells.

METHODS

Primary isolated HSC from FVB/NJ mice and the immortalized human HSC line TWNT-4 were culture-activated and incubated with Y-27632 and Y-33075 (10nM to 10μM) for 24h. Protein expression levels were analyzed by Western Blots and transcriptional levels of pro-fibrotic markers and proliferative markers were evaluated using real-time qPCR. Migration was investigated by wound-healing assay. Proliferation was assessed by BrdU assay. Contraction of HSC was measured using 3D collagen matrices after incubation with Y-27632 or Y-33075 in different doses.

RESULTS

Both Rho-kinase inhibitors, Y-27632 and Y-33075, reduced contraction, fibrogenesis and proliferation in activated primary mouse HSC (FVB/NJ) and human HSC line (TWNT-4) significantly. Y-33075 demonstrated a 10-times increased potency compared to Y-27632. Surprisingly, both inhibitors mediated a substantial and unexpected increase in migration of HSC in FVB/NJ.

CONCLUSION

ROCK inhibition by the tested compounds decreased contraction but increased migration. Y-33075 proved more potent than Y27632 in the inhibition of contraction of HSCs and should be further evaluated in chronic liver disease.

Protein Acetylation Increased Risk of Fibrosis-Related Liver Cancer

Objective

The occurrence of liver fibrosis and fibrosis-related liver cancer is the reason for the increase in morbidity and mortality worldwide. Transforming growth factor-β2 (TGF-β2) is an important mediator of chronic liver fibrosis. This study aims to find the molecular mechanism that mediates HBV infection and induces TGF-β2 and verifies that CREB binding protein acetylation mediates HBV infection and induces TGF-β2 expression.

Methods

The acetylated proteins were extracted from HepG2-NTCP cells and HBV-infectedHepG2-NTCP cells. The acetylated proteins were screened by modification enrichment technology and database search. Protein annotation, motif analysis of modification sites, and protein function enrichment analysis of these proteins were performed to roughly clarify the location and function of these acetylated modification proteins in cells. Acylated proteins enriched in the TGF-β pathway were obtained by KEGG pathway enrichment analysis. The effect of the selected acetylated modification protein on the TGF-β pathway was verified by experiments, that is, the target protein gene was knocked out by siRNA, and the expression level of the TGF-β2 was detected by qRT-PCR.

Results

Proteins were extracted from HepG2-NTCP cells and HepG2-NTCP cells infected with HBV, and differential acetylation modification proteins were screened. The target protein CREB binding protein was screened by modification enrichment technology and database search. The aggregation analysis of TGF-β pathway showed that CREB binding protein was acetylated at amino acid positions 434 and 439, and enriched in the TGF-β signaling pathway. siRNA targeting CREB binding protein was transfected, and the expression of TGF-β2 in cells was detected by qRT-PCR and western blot, respectively. It was verified that HBV infection-inducedCREB-binding protein acetylation regulated the high expression of TGF-β2.

Conclusion

After HBV infection, CREBBP acetylation was up-regulated, which promoted the high expression of TGF-β2.

Metabolic Role of Autophagy in the Pathogenesis and Development of NAFLD

Non-alcoholic fatty liver disease (NAFLD) is a spectrum of liver disease, ranging from simple steatosis to hepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Liver fibrosis, which portends a poor prognosis in NAFLD, is characterized by the excessive accumulation of extracellular matrix (ECM) proteins resulting from abnormal wound repair response and metabolic disorders. Various metabolic factors play crucial roles in the progression of NAFLD, including abnormal lipid, bile acid, and endotoxin metabolism, leading to chronic inflammation and hepatic stellate cell (HSC) activation. Autophagy is a conserved process within cells that removes unnecessary or dysfunctional components through a lysosome-dependent regulated mechanism. Accumulating evidence has shown the importance of autophagy in NAFLD and its close relation to NAFLD progression. Thus, regulation of autophagy appears to be beneficial in treating NAFLD and could become an important therapeutic target.

Cancer Stem Cell and Hepatic Stellate Cells in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common liver cancer. It is highly lethal and has high recurrence. Death among HCC patients occur mainly due to tumor progression, recurrence, metastasis, and chemoresistance. Cancer stem cells (CSCs) are cell subpopulations within the tumor that promote invasion, recurrence, metastasis, and drug resistance. Hepatic stellate cells (HSCs) are important components of the tumor microenvironment (TME) responsible for primary secretory ECM proteins during liver injury and inflammation. These cells promote fibrogenesis, infiltrate the tumor stroma, and contribute to HCC development. Interactions between HSC and CSC and their microenvironment help promote carcinogenesis through different mechanisms. This review summarizes the roles of CSCs and HSCs in establishing the TME in primary liver tumors and describes their involvement in HCC chemoresistance.

Hyperphosphorylation of EGFR/ERK signaling facilitates long-term arsenite-induced hepatocytes epithelial-mesenchymal transition and liver fibrosis in sprague-dawley rats

Arsenic is a well known environmental hazardous material, chronic arsenic exposure results in different types of liver damage. Among them, liver fibrosis has become a research hotspot because of its reversibility, while the underlying mechanism is still unclear. Previous studies revealed that EGFR/ERK signaling appears to play an important role in fibrosis diseases. In this study, sprague-dawley rats were exposed to different doses of arsenite for 36 weeks to investigate the roles of EGFR/ERK signaling on arsenite-induced liver fibrogenesis. Our results showed that long-term arsenite exposure induced liver fibrosis, accompanied by hepatic stellate cells (HSCs) activation, excessive serum secretion of extracellular matrix (ECM), and hepatocytes epithelial-mesenchymal transformation (EMT). In addition, arsenite exposure caused hyperphosphorylation of EGFR/ERK signaling in liver tissue of rats, indicating that EGFR/ERK signaling may be involved in arsenite-induced liver fibrosis. Indeed, erlotinib (a specific phosphorylation inhibitor of EGFR) intervention significantly decreased arsenite induced hyperphosphorylation of EGFR/ERK signaling, thereby suppressed hepatocytes EMT process and alleviated liver fibrogenesis in arsenite exposed rats. In summary, the present study provides evidences showing that hyperphosphorylation of EGFR/ERK signaling facilitates long-term arsenite-induced hepatocytes EMT and liver fibrosis in rats, which brings new insights into the pathogenesis of arsenic-induced liver injury.

Integrative analysis implicates the significance of m6A in the liver fibrosis of biliary atresia by regulating THY1

Whether N6-methyladenosine (m6A) is involved in biliary atresia (BA) remains undefined. Herein, we comprehensively evaluated the m6A profile in BA. When compared with normal controls, BA had an elevated m6A level with upregulated m6A writers. The m6A level was correlated with liver function, stage of fibrosis and jaundice clearance in BA. Methylated RNA immunoprecipitation sequencing (MeRIP-seq) demonstrated an altered m6A topology in BA. MeRIP-seq and RNA sequencing filtered out 130 m6A-modified genes, which were enriched in fibrogenetic pathways. MeRIP-qPCR in vivo and interventions of LX-2 and primary HSCs in vitro validated the regulatory role of m6A on COL1A1 and THY1. THY1+ myofibroblasts expanded in portal area of BA, and highly expressed profibrogenic genes (COL1A1, MMP2, PDGFRA, and DCN). THY1 was correlated with liver fibrosis and jaundice clearance in BA. Bulk array (GSE46960, GSE15235), single-cell RNA sequencing (GSE136103), primary HSC interventions, and co-immunoprecipitation revealed that THY1 was correlated with extracellular matrix organization, promoted HSC activation, showed higher interactions with integrins on myeloid cells in cholestatic fibrosis, and was correlated with native liver survival in BA. Our study highlights the significance of m6A in BA-induced liver fibrogenesis by regulating THY1, shedding new light on the novel therapies to alleviate liver fibrosis by targeting m6A/THY1 axis in BA.

Depletion of Tgfbr2 in hepatocytes alleviates liver fibrosis and restores hepatic function in fibrotic mice

OBJECTIVES

Previous studies have demonstrated the pivotal role of transforming growth factor (TGF)-β signaling in activating hepatic stellate cells during liver fibrosis. In this study we aimed to demonstrate the effects and underlying mechanism of TGF-β signaling in hepatocytes on hepatic fibrogenesis.

METHODS

Hepatocyte-specific Tgfbr2-knockout (Tgfbr2^HKO ) mice were generated by AAV8-TBG-Cre injection via the tail vein of Tgfbr2^f/f mice. CCl₄ was injected intraperitoneally twice a week for 4 weeks to establish the fibrotic mouse model. The expression of the fibrogenesis markers was evaluated by immunohistochemistry, western blot, and real-time polymerase chain reaction (PCR). RNA-seq analysis was used to detect the transcriptional profiles of primary hepatocytes isolated from Tgfbr2^HKO mice and control mice.

RESULTS

The expression of TβR2 (Tgfbr2) was markedly upregulated in hepatocytes of the fibrotic liver. Tgfbr2 depletion in hepatocytes decreased the expressions of profibrogenic markers (Col1a1 and Acta2) in the CCl₄ -treated fibrotic liver. RNA-seq analysis revealed that Tgfbr2 deletion in hepatocytes significantly reduced the inflammatory response and suppressed epithelial-mesenchymal transition of hepatocytes accompanied by upregulation of the metabolic pathways during liver fibrosis. Moreover, the expressions of hepatocyte nuclear factors (HNFs), including Hnf4α, Foxa1, Foxa2, and Foxa3, which are important for maintaining liver metabolism and homeostasis, were decreased in fibrotic livers and significantly increased after Tgfbr2 blockade.

CONCLUSION

Blocking the TGF-β signaling pathway in hepatocytes reduces hepatic fibrosis and improves hepatic function in fibrotic livers.

Effects of exosomes of mesenchymal stem cells on cholesterol-induced hepatic fibrogenesis

Objectives

Free cholesterol in the diet can cause liver fibrosis by accumulating in Hepatic stellate cells (HSCs). The rate of mortality of this disease is high worldwide and there is no definite remedy for it, but might be treated by anti-fibrotic therapies. MSCs-derived exosomes are known as the new mechanism of cell-to-cell communication, showing that exosomes can be used as a new treatment. In this study, we investigated the ability of exosomes of WJ-MSCs as a new remedy to reduce cholesterol-induced liver fibrosis in the LX2 cell line.

Materials and Methods

MSCs were isolated from Wharton's jelly of the umbilical cord and the exosomes were extracted. The LX2 cell line was cultured in DMEM medium with 10% FBS, then cells were treated with 75 and 100 μM concentrations of cholesterol for 24 hr. The mRNA expression of TGF-β, αSMA, and collagen1α genes, and the level of Smad3 protein were measured to assess liver fibrosis.

Results

Cholesterol increased the expression of TGF-β, αand -SMA, and collagen1α genes by increasing the phosphorylation of the Smad3 protein. Treatment with Exosomes significantly reduced the expression of TGF-β, α-SMA, and collagen1α genes (fibrosis genes). Treatment with exosomes prevented the activation of HSCs by inhibiting the phosphorylation of the Smad3 protein.

Conclusion

The exosomes of WJ-MSCs can inhibit the TGFβ/Smad3 signaling pathway preventing further activation of HSCs and progression of liver fibrosis. So, the exosomes of WJ-MSCs s could be introduced as a treatment for liver failure.

Roxarsone inhibits hepatic stellate cell activation and ameliorates liver fibrosis by blocking TGF-β1/Smad signaling pathway

Hepatic fibrosis is a pathological change caused by chronic liver injury and self-repair, and it is the inevitable stage of the development of chronic liver disease to cirrhosis or even liver cancer. Activation of hepatic stellate cells (HSCs) is a core event in the development of liver fibrosis and blockage of the activation of HSCs has been shown to alleviate liver fibrosis. Roxarsone, an organoarsenic additive, with antibiotic effect, growth promotion and improving feed efficiency, is widely used in livestock and animal production. The purpose of this study was to evaluate the therapeutic effect of Roxarsone on liver fibrosis and explore the possible mechanism. We found that Roxarsone could inhibit transforming growth factor-β1 (TGF-β1) induced the activation of HSCs and weaken the migration ability. Moreover, Roxarsone administration significantly ameliorated CCl₄-induced liver fibrosis in mice with improvement of liver function and decreases of deposition of extracellular matrix (ECM). Mechanism investigations revealed that Roxarsone specifically inhibited the activation of TGF-β1/Smad signaling pathway, but had no effect on MAPK and PI3K/AKT pathways. These results suggest that Roxarsone has a protective effect on liver fibrosis which provides a new candidate for the treatment of liver fibrosis.

Melatonin alleviates diet-induced steatohepatitis by targeting multiple cell types in the liver to suppress inflammation and fibrosis

The pathogenesis of nonalcoholic steatohepatitis (NASH), a severe stage of nonalcoholic fatty liver disease, is complex and implicates multiple cell interactions. However, therapies for NASH that target multiple cell interactions are still lacking. Melatonin (MEL) alleviates NASH with mechanisms not yet fully understood. Thus, we herein investigate the effects of MEL on key cell types involved in NASH, including hepatocytes, macrophages, and stellate cells. In a mouse NASH model with feeding of a methionine and choline-deficient (MCD) diet, MEL administration suppressed lipid accumulation and peroxidation, improved insulin sensitivity, and attenuated inflammation and fibrogenesis in the liver. Specifically, MEL reduced proinflammatory cytokine expression and inflammatory signal activation and attenuated CD11C+CD206- M1-like macrophage polarization in the liver of NASH mice. The reduction of proinflammatory response by MEL was also observed in the lipopolysaccharide-stimulated Raw264.7 cells. Additionally, MEL increased liver fatty acid β-oxidation, leading to reduced lipid accumulation, and restored the oleate-loaded primary hepatocytes. Finally, MEL attenuated hepatic stellate cell (HSC) activation and fibrogenesis in the liver of MCD-fed mice and in LX-2 human HSCs. In conclusion, MEL acts on multiple cell types in the liver to mitigate NASH-associated phenotypes, supporting MEL or its analog as potential treatment for NASH.

Genome-wide DNA methylation dynamics in carbon tetrachloride-induced mice liver fibrosis

Objectives

Many persistent harmful stimuli can result in chronic liver diseases, which lead to about 2 million deaths per year in the whole world. Liver fibrosis was found to exist in all kinds of chronic liver diseases. Many studies suggested that DNA methylation was associated with the pathogenesis of liver fibrosis. This study aimed to quantitatively detect DNA methylation changes in the whole genome in fibrotic liver tissues of mice.

Materials and Methods

Liver fibrosis was induced by intraperitoneal injection of carbon tetrachloride (CCl₄) for 4 weeks. A genome-wide methylome analysis was performed using 850K BeadChips assays. The methylation status of 27 CpG dinucleotides located in 3 genes was detected by pyrosequencing to confirm chip data accuracy, and mRNA expressions of these 3 genes were examined by RT-qPCR methods.

Results

A total of 130,068 differentially methylated sites (DMS, 58,474 hypermethylated, and 71,594 hypomethylated) between fibrotic liver tissues and control mice liver tissues were identified by the 850k BeadChips array. Consistency between pyrosequencing data and 850k BeadChips array data was observed (R=0.928; P<0.01). Apoptosis, positive regulation of transcription of Notch receptor target, and negative regulation of p38MAPK signal cascade activities were significantly enriched in the Gene Ontology (GO) analyses. Cholesterol metabolism, bile secretion, and more biosynthesis and metabolism pathways were enriched in KEGG pathway analyses. Ten key genes were identified by the Cytoscape plugin cytoHubba.

Conclusion

7850 genes were found to have methylation change in fibrotic liver tissues of mice, which facilitates future research for clinical application.

Glycocholic acid aggravates liver fibrosis by promoting the up-regulation of connective tissue growth factor in hepatocytes

AIMS

The precise role of bile acid in the progression of liver fibrosis has yet to be elucidated. In this study, common bile duct ligation was used as an in vivo mouse model for the evaluation of bile acids that promote liver connective tissue growth factor expression.

MAIN METHODS

Primary rat and mice hepatocytes, as well as primary rat hepatic stellate and HepaRG cells were evaluated as in vitro models for promoting the expression of connective tissue growth factor by bile acids.

KEY FINDINGS

Compared with taurochenodeoxycholic acid, glycochenodeoxycholic acid, and taurocholic acid, glycocholic acid (GCA) most strongly promoted the secretion of connective tissue growth factor in mouse primary hepatocytes, rat primary hepatocytes and HepaRGs. GCA did not directly promote the activation of hepatic stellate cells. The administration of GCA in mice with ligated bile ducts promotes the progression of liver fibrosis, which may promote the yes-associated protein of hepatocytes into the nucleus, resulting in the hepatocytes secreting more connective tissue growth factor for hepatic stellate cell activation. In conclusion, our data showed that GCA can induce the expression of connective tissue growth factor in hepatocytes by promoting the nuclear translocation of yes-associated protein, thereby activating hepatic stellate cells.

SIGNIFICANCE

Our findings help to elucidate the contribution of GCA to the progression of hepatic fibrosis in cholestatic disease and aid the clinical monitoring of cholestatic liver fibrosis development.

Hastatoside attenuatescarbon tetrachloride-induced liver fibrosis by targeting glycogen synthase kinase-3β

BACKGROUND

Hastatoside is an iridoid glycoside extracted from the herb, Verbena officinalis, that exerts various pharmacological effects, including anti-inflammatory, sleep-promoting, and analgesic effects. However, only a few studies have reported the efficacy of hastatoside in liver fibrosis. Liver fibrosis is a pathophysiological process, and its persistence can seriously affect the quality of life and well-being of the patients.

HYPOTHESIS/PURPOSE

This study aimed to investigate the role of hastatoside on liver fibrosis and its possible underlying mechanisms.

METHODS

C57BL/6 J mice with carbon tetrachloride (CCl₄)-induced hepatic fibrosis were used as the in vivo models. Histological features of the liver were observed using Masson's trichrome and hematoxylin-eosin staining. Alanine aminotransferase and aspartate aminotransferase levels and the hepatic fibrosis indices (type 3 procollagen, laminin, and hyaluronic acid) were measured using corresponding assay kits. LX-2 human hepatic stellate cells (HSCs) stimulated with the transforming growth factor β1 were used as the vitro models. Transfection of the glycogen synthase kinase (GSK)-3β small interfering RNA (siRNA) and β-catenin plasmids was also performed in vitro. Protein levels of GSK-3β, phospho-GSK-3β (Ser 9), α-smooth muscle actin, collagen type I alpha 1, c-Myc, cyclin D1, and β-catenin were determined via western blotting. Moreover, the p-GSK-3β:GSK-3β ratio was calculated to determine the GSK-3β activity.

RESULTS

Hastatoside prevented CCl₄-induced liver injury and histological damage. It inhibited the upregulation of α-SMA and Col1α1 levels in a CCl₄-induced mouse hepatic fibrosis model. In vitro, hastatoside inhibited the proliferation and activation of HSCs by decreasing the expression levels of cyclin D1 and c-Myc and the proportion of LX-2 cells activated in the G0/G1 phase. Molecular docking results showed that hastatoside bound to GSK-3β. Hastatoside significantly increased the GSK-3β activity and inhibited the downstream effector expression of β-catenin.

CONCLUSION

These findings suggest that hastatoside can bind to GSK-3β and promote its activity, while inhibiting the GSK-3β downstream effector expression of β-catenin, thereby inhibiting the activation and proliferation of HSCs, which further prevents the development of liver fibrosis. These results provide innovative insights into the underlying liver fibrosis. Moreover, hastatoside is a potential anti-fibrosis monomer that can potentially be used for the treatment of liver fibrosis.

Formulating elafibranor and obeticholic acid with phospholipids decreases drug-induced association of SPARC to extracellular vesicles from LX-2 human hepatic stellate cells

Chronic hepatic diseases often compromise liver function and are directly responsible for up to two million yearly deaths world-wide. There are yet no treatment options to solve this global medical need. Experimental drugs elafibranor (Ela) and obeticholic acid (OA) appeared promising in numerous earlier studies, but they recently struggled to show significant benefits in patients. Little is known on the drugs' impact on hepatic stellate cells (HSCs), key players in liver fibrogenesis. We recently reported a beneficial effect of polyenylphosphatidylcholines (PPCs)-rich formulations in reverting fibrogenic features of HSCs, including differences in their extracellular vesicles (EVs). Here, we newly formulated Ela and OA in PPC liposomes and evaluated their performance on the LX-2 (human HSC) cell line through our rigorous methods of EV-analysis, now expanded to include lipidomics. We show that direct treatments with Ela and OA increase EV-associated secreted protein acidic and cysteine rich (SPARC), a matricellular protein overexpressed in fibrogenesis. However, our results suggest that this potentially damaging drugs' action to HSCs could be mitigated when delivering them with lipid-based formulations, most notably with a PPC-rich phospholipid inducing specific changes in the cellular and EV phospholipid composition. Thus, EV analysis substantially deepens evaluations of drug performances and delivery strategies.

SARS-CoV-2-mediated liver injury: pathophysiology and mechanisms of disease

BACKGROUND

SARS-CoV-2-induced severe inflammatory response can be associated with severe medical consequences leading to multi-organ failure, including the liver. The main mechanism behind this assault is the aggressive cytokine storm that induces cytotoxicity in various organs. Of interest, hepatic stellate cells (HSC) respond acutely to liver injury through several molecular mechanisms, hence furthering the perpetuation of the cytokine storm and its resultant tissue damage. In addition, hepatocytes undergo apoptosis or necrosis resulting in the release of pro-inflammatory and pro-fibrogenic mediators that lead to chronic liver inflammation.

AIMS

The aim of this review is to summarize available data on SARS-CoV-2-induced liver inflammation in addition to evaluate the potential effect of anti-inflammatory drugs in attenuating SARS-CoV-2-induced liver inflammation.

METHODS

Thorough PubMed search was done to gather and summarize published data on SARS-CoV-2-induced liver inflammation. Additionally, various anti-inflammatory potential treatments were also documented.

RESULTS

Published data documented SARS-CoV-2 infection of liver tissues and is prominent in most liver cells. Also, histological analysis showed various features of tissues damage, e.g., hepatocellular necrosis, mitosis, cellular infiltration, and fatty degeneration in addition to microvesicular steatosis and inflammation. Finally, the efficacy of the different drugs used to treat SARS-CoV-2-induced liver injury, in particular the anti-inflammatory remedies, are likely to have some beneficial effect to treat liver injury in COVID-19.

CONCLUSION

SARS-CoV-2-induced liver inflammation is a serious condition, and drugs with potent anti-inflammatory effect can play a major role in preventing irreversible liver damage in COVID-19.

[An update of understanding of the hepatic vascular system and new research strategies]

Although the portal vessels, liver sinusoids, and central vessels are known to contain microvessels with different structures and functions, their changes and roles in liver fibrogenesis have not been fully understood. Recent studies suggest that in mouse models of liver fibrogenesis, vascular changes can occur at a very early stage, and different liver vessels undergo different changes and play different roles, as shown by a decreased number of portal vessels, increased sinusoid capillarization and increased central vessels. The increase of portal vessels alleviates liver fibrosis, while the increase of central vessels and sinusoid capillarization aggravates liver fibrosis. A full understanding of the regulatory mechanisms of each of these vessels is vital for treatment of liver fibrosis. A combined regulation of different endothelial cell (EC) regulatory signaling pathways for vascular normalization may provide new strategies for liver fibrosis therapy. Further studies of the changes and functions of blood vessels in different liver diseases, liver development and regeneration may bring about important breakthroughs. This review summarizes the changes of 3 hepatic microvessels and their roles in liver fibrogenesis and propose the major directions of future studies in this field.

Gemigliptin Alleviates Succinate-Induced Hepatic Stellate Cell Activation by Ameliorating Mitochondrial Dysfunction

BACKGRUOUND

Dipeptidyl peptidase-4 inhibitors (DPP-4Is) are used clinically as oral antidiabetic agents. Although DPP-4Is are known to ameliorate liver fibrosis, the protective mechanism of DPP-4Is in liver fibrosis remains obscure. In this study, gemigliptin was used to investigate the potential of DPP-4Is to alleviate the progression of liver fibrosis.

METHODS

To clarify the effects and mechanisms of gemigliptin, we conducted various experiments in LX-2 cells (immortalized human hepatic stellate cells [HSCs], the principal effectors of hepatic fibrogenesis), which were activated by succinate and exhibited elevated expression of α-smooth muscle actin, collagen type 1, and pro-inflammatory cytokines and increased cell proliferation. In vivo, we examined the effects and mechanisms of gemigliptin on a high-fat, high-cholesterol-induced mouse model of nonalcoholic steatohepatitis (NASH).

RESULTS

Gemigliptin decreased the expression of fibrogenesis markers and reduced the abnormal proliferation of HSCs. In addition, gemigliptin reduced the succinate-induced production of mitochondrial reactive oxygen species (ROS), intracellular ROS, and mitochondrial fission in HSCs. Furthermore, in the mouse model of NASH-induced liver fibrosis, gemigliptin alleviated both liver fibrosis and mitochondrial dysfunction.

CONCLUSION

Gemigliptin protected against HSC activation and liver fibrosis by alleviating mitochondrial dysfunction and ROS production, indicating its potential as a strategy for preventing the development of liver disease.

A hierarchical regulatory network ensures stable albumin transcription under various pathophysiological conditions

BACKGROUND AND AIMS

It remains unknown how patients with liver failure maintain essential albumin levels. Here, we delineate a hierarchical transcription regulatory network that ensures albumin expression under different disease conditions.

APPROACH AND RESULTS

We examined albumin levels in liver tissues and serum in 157 patients, including 84 with HCC, 38 decompensated cirrhosis, and 35 acute liver failure. Even in patients with liver failure, the average serum albumin concentrations were 30.55 g/L. In healthy subjects and patients with chronic liver diseases, albumin was expressed in hepatocytes. In patients with massive hepatocyte loss, albumin was expressed in liver progenitor cells (LPCs). The albumin gene (ALB) core promoter possesses a TATA box and nucleosome-free area, which allows constitutive RNA polymerase II binding and transcription initiation. Chromatin immunoprecipitation assays revealed that hepatocyte nuclear factor 4 alpha (HNF4α), CCAAT/enhancer-binding protein alpha (C/EBPα), and forkhead box A2 (FOXA2) bound to the ALB enhancer. Knockdown of either of these factors reduced albumin expression in hepatocytes. FOXA2 acts as a pioneer factor to support HNF4α and C/EBPα. In hepatocytes lacking HNF4α and C/EBPα expression, FOXA2 synergized with retinoic acid receptor (RAR) to maintain albumin transcription. RAR nuclear translocation was induced by retinoic acids released by activated HSCs. In patients with massive hepatocyte loss, LPCs expressed HNF4α and FOXA2. RNA sequencing and quantitative PCR analyses revealed that lack of HNF4α and C/EBPα in hepatocytes increased hedgehog ligand biosynthesis. Hedgehog up-regulates FOXA2 expression through glioblastoma family zinc finger 2 binding to the FOXA2 promoter in both hepatocytes and LPCs.

CONCLUSIONS

A hierarchical regulatory network formed by master and pioneer transcription factors ensures essential albumin expression in various pathophysiological conditions.

Mechanotransduction in the pathogenesis of non-alcoholic fatty liver disease

Mechanobiology is a domain of interdisciplinary research that aims to explore the impact of physical force, applied externally or internally, on cell and tissue function, including development, growth, and differentiation. Mechanotransduction is a term that describes how cells sense physical forces (such as compression, stretch, and shear stress), convert them into biochemical signals, and mount adaptive responses integrated by the nucleus. There is accumulating evidence that mechanical forces extensively inform the biological behaviour of liver cells in health and disease. Recent research has elucidated many cellular and molecular mechanisms involved in this process including the pleiotropic control and diverse effects of the paralogous transcription co-activators YAP/TAZ, which play a prominent role in mechanotransduction. The liver sinusoids represent a unique microenvironment in which cells are exposed to mechanical cues originating in the cytoskeleton and at interfaces with adjacent cells, the extracellular matrix, and vascular or interstitial fluids. In non-alcoholic fatty liver disease (NAFLD), hepatocellular lipid accumulation and ballooning, activation of inflammatory responses, dysfunction of liver sinusoidal endothelial cells, and transdifferentiation of hepatic stellate cells into a pro-contractile and pro-fibrotic phenotype have been associated with aberrant cycles of mechanosensing and mechanoresponses. The downstream consequences of disrupted mechanical homeostasis likely contribute to the progression of NAFLD and promote the development of portal hypertension, cirrhosis, and hepatocellular carcinoma. Identification of molecular targets involved in pathogenic mechanotransduction will allow for the development of novel strategies to prevent the progression of liver disease in NAFLD.

TRPM8 deficiency attenuates liver fibrosis through S100A9-HNF4α signaling

Background

Liver fibrosis represent a major global health care burden. Data emerging from recent advances suggest TRPM8, a member of the transient receptor potential (TRP) family of ion channels, plays an essential role in various chronic inflammatory diseases. However, its role in liver fibrosis remains unknown. Herein, we assessed the potential effect of TRPM8 in liver fibrosis.

Methods

The effect of TRPM8 was evaluated using specimens obtained from classic murine models of liver fibrosis, namely wild-type (WT) and TRPM8^−/− (KO) fibrotic mice after carbon tetrachloride (CCl₄) or bile duct ligation (BDL) treatment. The role of TRPM8 was systematically evaluated using specimens obtained from the aforementioned animal models after various in vivo and in vitro experiments.

Results

Clinicopathological analysis showed that TRPM8 expression was upregulated in tissue samples from cirrhosis patients and fibrotic mice. TRPM8 deficiency not only attenuated inflammation and fibrosis progression in mice but also helped to alleviate symptoms of cholangiopathies. Moreover, reduction in S100A9 and increase in HNF4α expressions were observed in liver of CCl₄- and BDL- treated TRPM8^−/− mice. A strong regulatory linkage between S100A9 and HNF4α was also noticed in L02 cells that underwent siRNA-mediated S100A9 knockdown and S100A9 overexpressing plasmid transfection. Lastly, the alleviative effect of a selective TRPM8 antagonist was confirmed in vivo.

Conclusions

These findings suggest TRPM8 deficiency may exert protective effects against inflammation, cholangiopathies, and fibrosis through S100A9-HNF4α signaling. M8-B might be a promising therapeutic candidate for liver fibrosis.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13578-022-00789-4.

SENP1 prevents steatohepatitis by suppressing RIPK1-driven apoptosis and inflammation

Activation of RIPK1-driven cell death and inflammation play important roles in the progression of nonalcoholic steatohepatitis (NASH). However, the mechanism underlying RIPK1 activation in NASH remains unclear. Here we identified SENP1, a SUMO-specific protease, as a key endogenous inhibitor of RIPK1. SENP1 is progressively reduced in proportion to NASH severity in patients. Hepatocyte-specific SENP1-knockout mice develop spontaneous NASH-related phenotypes in a RIPK1 kinase-dependent manner. We demonstrate that SENP1 deficiency sensitizes cells to RIPK1 kinase-dependent apoptosis by promoting RIPK1 activation following TNFα stimulation. Mechanistically, SENP1 deSUMOylates RIPK1 in TNF-R1 signaling complex (TNF-RSC), keeping RIPK1 in check. Loss of SENP1 leads to SUMOylation of RIPK1, which re-orchestrates TNF-RSC and modulates the ubiquitination patterns and activity of RIPK1. Notably, genetic inhibition of RIPK1 effectively reverses disease progression in hepatocyte-specific SENP1-knockout male mice with high-fat-diet-induced nonalcoholic fatty liver. We propose that deSUMOylation of RIPK1 by SENP1 provides a pathophysiologically relevant cell death-restricting checkpoint that modulates RIPK1 activation in the pathogenesis of nonalcoholic steatohepatitis.

Suppressing circ_0008494 inhibits HSCs activation by regulating the miR-185-3p/Col1a1 axis

Background: Hepatic fibrosis (HF) is characterized by activation of hepatic stellate cells (HSCs) and extensive deposition of extracellular matrix components, especially collagens. However, effective antifibrotic therapies are still lacking. Recently, circular RNAs (circRNAs) have been identified as novel regulators of HF. Methods: circRNAs profile was screened by RNA sequencing and the location of circ_0008494 was confirmed by fluorescence in situ hybridization assay in human HF tissues. Bioinformatics analysis was used for result prediction and dual-luciferase reporter, together with AGO-RIP and biotin-coupled miRNA capture assays, were used to determine miR-185-3p/collagen type I alpha 1 chain (Col1a1) as the target of circ_0008494. A stable circ_0008494-interfering human HSCs cell line was constructed and used to determine the regulatory mechanism of circ_0008494/miR-185-3p/Col1a1 axis. Results: circ_0008494 was abundantly and significantly over-expressed in human HF tissues and located at the cytoplasm of HSCs. Together, dual-luciferase reporter, AGO-RIP and biotin-coupled miRNA capture assays confirmed that circ_0008494 acted as a sponge of miR-185-3p. Cell functional experiments and rescue assays demonstrated suppressing circ_0008494 could inhibit activation, proliferation, migration of HSCs and promote their apoptosis through miR-185-3p. In particular, the HF indicator, Col1a1, was validated as the direct target of miR-185-3p and the suppression of circ_0008494 inhibited the expression of Col1a1 by releasing miR-185-3p. Conclusion: Knocking down circ_0008494 inhibited HSCs activation through the miR-185-3p/Col1a1 axis. circ_0008494 could be a promising treatment target for HF.

Hepatic kinome atlas: An in-depth identification of kinase pathways in liver fibrosis of humans and rodents

BACKGROUND AND AIMS

Resolution of pathways that converge to induce deleterious effects in hepatic diseases, such as in the later stages, have potential antifibrotic effects that may improve outcomes. We aimed to explore whether humans and rodents display similar fibrotic signaling networks.

APPROACH AND RESULTS

We assiduously mapped kinase pathways using 340 substrate targets, upstream bioinformatic analysis of kinase pathways, and over 2000 random sampling iterations using the PamGene PamStation kinome microarray chip technology. Using this technology, we characterized a large number of kinases with altered activity in liver fibrosis of both species. Gene expression and immunostaining analyses validated many of these kinases as bona fide signaling events. Surprisingly, the insulin receptor emerged as a considerable protein tyrosine kinase that is hyperactive in fibrotic liver disease in humans and rodents. Discoidin domain receptor tyrosine kinase, activated by collagen that increases during fibrosis, was another hyperactive protein tyrosine kinase in humans and rodents with fibrosis. The serine/threonine kinases found to be the most active in fibrosis were dystrophy type 1 protein kinase and members of the protein kinase family of kinases. We compared the fibrotic events over four models: humans with cirrhosis and three murine models with differing levels of fibrosis, including two models of fatty liver disease with emerging fibrosis. The data demonstrate a high concordance between human and rodent hepatic kinome signaling that focalizes, as shown by our network analysis of detrimental pathways.

CONCLUSIONS

Our findings establish a comprehensive kinase atlas for liver fibrosis, which identifies analogous signaling events conserved among humans and rodents.

The correlation between neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio with nonalcoholic fatty liver disease: a cross-sectional study

OBJECTIVE

The aim of this study is to investigate the correlation between neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) with nonalcoholic fatty liver disease (NAFLD).

METHODS

All subjects underwent medical check-ups, which included the measurement of basic clinical, biochemical tests and imaging tests. Univariate and multivariate logistic regression models and piece-wise linear regression were used to assess the relationship between NLR and PLR with NAFLD.

RESULTS

All participants were divided into two groups: the Non-NAFLD group and the NAFLD group. Univariate analysis model indicated PLR was negatively correlated with NAFLD (P &lt; 0.001) and NLR was not significantly associated with NAFLD (P &gt; 0.05). Multiple logistic regression showed that no correlation between NLR and PLR with NAFLD after adjusting all covariates (P &gt; 0.05). Interestingly, a nonlinear association was detected between NLR and PLR with NAFLD by piece-wise linear regression adjusting for all confounding factors. The inflection points of NLR and PLR were 1.23 and 42.29, respectively. On the left side of the inflection point (NLR &lt; 1.23), a positive correlation was detected between NLR and NAFLD (β = 2.35, 95% CI: 1.20~4.61, P = 0.013). And PLR was found to be negatively associated with NAFLD on the right side of the inflection point (β = 0.99, 95% CI: 0.98~0.99, P &lt; 0.001).

CONCLUSION

This study demonstrated that the relationship between NLR and PLR with NAFLD was nonlinear after adjusting for potential confounding factors. The result suggested that PLR ≥ 42.29 might be a protective factor of NAFLD, while NLR &lt; 1.23 might be a risk factor of NAFLD.

Fatty Liver/Adipose Tissue Dual-Targeting Nanoparticles with Heme Oxygenase-1 Inducer for Amelioration of Obesity, Obesity-Induced Type 2 Diabetes, and Steatohepatitis

Persistent uptake of high-calorie diets induces the storage of excessive lipid in visceral adipose tissue. Lipids secreted from obese adipose tissue are accumulated in peripheral tissues such as the liver, pancreas, and muscle, and impair insulin sensitivity causing type 2 diabetes mellitus (T2DM). Furthermore, the accumulation of inflammatory cytokines and lipids in the liver induces apoptosis and fibrogenesis, and ultimately causes nonalcoholic steatohepatitis (NASH). To modulate obese tissue environments, it is challenged to selectively deliver inducers of heme oxygenase-1 (HO-1) to adipose tissue with the aid of a prohibitin targeting drug delivery system. Prohibitin binding peptide (PBP), an oligopeptide targeting prohibitin rich in adipose tissue, is conjugated on the surface of Hemin- or CoPP-loaded poly(lactide-co-glycolide) nanoparticles (PBP-NPs). PBP-NPs efficiently differentiate lipid storing white adipocytes into energy-generating brown adipocytes in T2DM and NASH models. In addition, PBP-NPs are found to target prohibitin overexpressed fatty liver in the NASH model and inhibit hepatic uptake of circulating lipids. Furthermore, PBP-NPs switch phenotypes of inflammatory macrophages in damaged organs and lower inflammation. Taken together, dual-targeted induction of HO-1 in fatty adipose and liver tissues is proven to be a promising therapeutic strategy to ameliorate obesity, insulin resistance, and steatohepatitis by lowering lipids and cytokines.

Tracking matricellular protein SPARC in extracellular vesicles as a non-destructive method to evaluate lipid-based antifibrotic treatments

Uncovering the complex cellular mechanisms underlying hepatic fibrogenesis could expedite the development of effective treatments and noninvasive diagnosis for liver fibrosis. The biochemical complexity of extracellular vesicles (EVs) and their role in intercellular communication make them an attractive tool to look for biomarkers as potential alternative to liver biopsies. We developed a solid set of methods to isolate and characterize EVs from differently treated human hepatic stellate cell (HSC) line LX-2, and we investigated their biological effect onto naïve LX-2, proving that EVs do play an active role in fibrogenesis. We mined our proteomic data for EV-associated proteins whose expression correlated with HSC treatment, choosing the matricellular protein SPARC as proof-of-concept for the feasibility of fluorescence nanoparticle-tracking analysis to determine an EV-based HSCs’ fibrogenic phenotype. We thus used EVs to directly evaluate the efficacy of treatment with S80, a polyenylphosphatidylcholines-rich lipid, finding that S80 reduces the relative presence of SPARC-positive EVs. Here we correlated the cellular response to lipid-based antifibrotic treatment to the relative presence of a candidate protein marker associated with the released EVs. Along with providing insights into polyenylphosphatidylcholines treatments, our findings pave the way for precise and less invasive diagnostic analyses of hepatic fibrogenesis.

A method is developed to isolate and characterize extracellular vesicles (EVs) from human hepatic stellate cells and proteomics reveals that the matricellular protein SPARC may be used as an EV marker after lipid-based antifibrotic treatment.

Oxysterol misbalance critically contributes to Wilson disease pathogenesis

Wilson disease (WD) is a metabolic disorder caused by inactivation of the copper-transporting ATPase 2 (ATP7B) and copper (Cu) overload in tissues. Excess Cu causes oxidative stress and pathologic changes with poorly understood mechanistic connections. In Atp7b^-/- mice with established liver disease, Cu overload activates the stress-sensitive transcription factor Nrf2 (nuclear factor erythroid-derived 2-like 2). Nrf2 targets, especially sulfotransferase 1e1 (Sult1e1), are strongly induced and cause elevation of sulfated sterols, whereas oxysterols are decreased. This sterol misbalance results in inhibition of the liver X receptor (LXR) and up-regulation of LXR targets associated with inflammatory responses. Pharmacological inhibition of Sult1e1 partially reverses oxysterol misbalance and LXR inhibition. Contribution of this pathway to advanced hepatic WD was demonstrated by treating mice with an LXR agonist. Treatment decreased inflammation by reducing expression of proinflammatory molecules, diminished fibrosis by down-regulating the noncanonical transforming growth factor-β signaling pathway, and improved liver morphology and function. Thus, the identified pathway is an important driver of WD.

Effect of Curcumin on Attenuation of Liver Cirrhosis via Genes/Proteins and Pathways: A System Pharmacology Study

Background: Liver cirrhosis is a life-threatening seqsuel of many chronic liver disorders of varying etiologies. In this study, we investigated protein targets of curcumin in liver cirrhosis based on a bioinformatics approach. Methods: Gene/protein associations with curcumin and liver cirrhosis were probed in drug−gene and gene−diseases databases including STITCH/DGIdb/DisGeNET/OMIM/DISEASES/CTD/Pharos and SwissTargetPrediction. Critical clustering groups (MCODE), hub candidates and critical hub genes in liver cirrhosis were identified, and connections between curcumin and liver cirrhosis-related genes were analyzed via Venn diagram. Interaction of hub genes with curcumin by molecular docking using PyRx-virtual screening tools was performed. Results: MCODE analysis indicated three MCODEs; the cluster (MCODE 1) comprised 79 nodes and 881 edges (score: 22.59). Curcumin database interactions recognized 318 protein targets. Liver cirrhosis genes and curcumin protein targets analysis demonstrated 96 shared proteins, suggesting that curcumin may influence 20 candidate and 13 hub genes, covering 81% of liver cirrhosis critical genes and proteins. Thirteen shared proteins affected oxidative stress regulation, RNA, telomerase activity, cell proliferation, and cell death. Molecular docking analysis showed the affinity of curcumin binding hub genes (Binding affinity: ΔG < −4.9 kcal/mol). Conclusions: Curcumin impacted on several critical liver cirrhosis genes mainly involved in extracellular matrix communication, focal adhesion, and the response to oxidative stress.

Potential Therapeutic Implication of Herbal Medicine in Mitochondria-Mediated Oxidative Stress-Related Liver Diseases

Mitochondria are double-membrane organelles that play a role in ATP synthesis, calcium homeostasis, oxidation-reduction status, apoptosis, and inflammation. Several human disorders have been linked to mitochondrial dysfunction. It has been found that traditional therapeutic herbs are effective on alcoholic liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD) which are leading causes of liver cirrhosis and hepatocellular carcinoma. The generation of reactive oxygen species (ROS) in response to oxidative stress is caused by mitochondrial dysfunction and is considered critical for treatment. The role of oxidative stress, lipid toxicity, and inflammation in NAFLD are well known. NAFLD is a chronic liver disease that commonly progresses to cirrhosis and chronic liver disease, and people with obesity, insulin resistance, diabetes, hyperlipidemia, and hypertension are at a higher risk of developing NAFLD. NAFLD is associated with a number of pathological factors, including insulin resistance, lipid metabolic dysfunction, oxidative stress, inflammation, apoptosis, and fibrosis. As a result, the improvement in steatosis and inflammation is enough to entice researchers to look into liver disease treatment. However, antioxidant treatment has not been very effective for liver disease. Additionally, it has been suggested that the beneficial effects of herbal medicines on immunity and inflammation are governed by various mechanisms for lipid metabolism and inflammation control. This review provided a summary of research on herbal medicines for the therapeutic implementation of mitochondria-mediated ROS production in liver disease as well as clinical applications through herbal medicine. In addition, the pathophysiology of common liver disorders such as ALD and NAFLD would be investigated in the role that mitochondria play in the process to open new therapeutic avenues in the management of patients with liver disease.

CD133-Src-TAZ signaling stimulates ductal fibrosis following DDC diet-induced liver injury

Chronic liver injury follows inflammation and liver fibrosis; however, the molecular mechanism underlying fibrosis has not been fully elucidated. In this study, the role of ductal WW domain-containing transcription regulator 1 (WWTR1)/transcriptional coactivator with PDZ-binding motif (TAZ) was investigated after liver injury. Ductal TAZ-knockout (DKO) mice showed decreased liver fibrosis following a Diethyl 1,4-dihydro-2,4,6-trimethyl-3,5-pyridinedicarboxylate (DDC) diet compared to wild-type (WT) mice, as evidenced by decreased expression levels of fibrosis inducers, including connective tissue growth factor (Ctgf)/cellular communication network factor 2 (CCN2), cysteine-rich angiogenic inducer 61 (Cyr61/CCN1), and transforming growth factor beta 1 (Tgfb1), in DKO mice. Similarly, TAZ-knockout (KO) cholangiocyte organoids showed decreased expression of fibrosis inducers. Additionally, the culture supernatant of TAZ-KO cholangiocyte organoids decreased the fibrogenic gene expression in liver stellate cells. Further studies revealed that prominin 1 (PROM1/CD133) stimulated TAZ for fibrosis. After the administration of DDC diet, fibrosis was decreased in CD133-KO (CD133-KO) mice compared to that in WT mice. Similarly, CD133-KO cholangiocyte organoids showed decreased Ctgf, Cyr61, and Tgfb1 expression levels compared to WT cholangiocyte organoids. Mechanistically, CD133 stabilized TAZ via Src activation. Inhibition of Src decreased TAZ levels. Similarly, CD133-knockdown HCT116 cells showed decreased TAZ levels, but reintroduction of active Src recovered the TAZ levels. Taken together, our results suggest that TAZ facilitates liver fibrosis after a DDC diet via the CD133-Src-TAZ axis.

Femtosecond laser attenuates oxidative stress, inflammation, and liver fibrosis in rats: Possible role of PPARγ and Nrf2/HO-1 signaling

Liver fibrosis is the excessive accumulation of extracellular matrix (ECM) proteins that occurs in chronic liver injury. Inflammation and oxidative stress play a key role in fibrogenesis which can develop into cirrhosis and carcinoma. Low-level laser therapy (LLLT) has promising therapeutic effects against fibrogenesis; however, the specific underlying mechanism is not fully elucidated. We investigated the potential of LLLT to attenuate carbon tetrachloride (CCl₄)-induced liver fibrosis in rats, focusing on oxidative injury, inflammatory response, and the possible role of PPARγ and Nrf2/HO-1 signaling. Rats were given CCl₄ and exposed to LLLT twice/week for 6 weeks and blood and liver samples were collected for analysis. CCl₄ caused liver injury and fibrosis manifested by hepatocyte injury, steatosis, inflammatory cell infiltration, and accumulation of collagen, elevated serum transaminases and bilirubin, and decreased albumin. ROS, MDA, NO, NF-κB p65, TNF-α, iNOS, TGF-β1, and IL-6 were increased in the liver of CCl₄-administered rats. Exposure to LLLT ameliorated histopathological alterations, collagen deposition, and liver function markers, and downregulated hepatic α-SMA, collagen 1A1, and collagen 3A1. In Addition, LLLT decreased ROS, MDA, NO, NF-κB p65, TGF-β1, and pro-inflammatory mediators, and enhanced antioxidant defenses. These effects were associated with upregulated PPARγ, Nrf2, and HO-1, both gene and protein expression. In conclusion, LLLT attenuated liver fibrosis by suppressing ECM production and deposition, oxidative injury and inflammation, and upregulating PPARγ and Nrf2/HO-1 signaling.

Identification of potential hub genes of gastric cancer

BACKGROUND

Gastric cancer (GC) is a malignant tumor originated from gastric mucosa epithelium. It is the third leading cause of cancer mortality in China. The early symptoms are not obvious. When it is discovered, it has developed to the advanced stage, and the prognosis is poor. In order to screen for potential genes for GC development, this study obtained GSE118916 and GSE109476 from the gene expression omnibus (GEO) database for bioinformatics analysis.

METHODS

First, GEO2R was used to identify differentially expressed genes (DEG) and the functional annotation of DEGs was performed by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The Search Tool for the Retrieval of Interacting Genes (STRING) tool was used to construct protein-protein interaction (PPI) network and the most important modules and hub genes were mined. Real time quantitative polymerase chain reaction assay was performed to verify the expression level of hub genes.

RESULTS

A total of 139 DEGs were identified. The functional changes of DEGs are mainly concentrated in the cytoskeleton, extracellular matrix and collagen synthesis. Eleven genes were identified as core genes. Bioinformatics analysis shows that the core genes are mainly enriched in many processes related to cell adhesion and collagen.

CONCLUSION

In summary, the DEGs and hub genes found in this study may be potential diagnostic and therapeutic targets.