Novel Insights on Notch signaling pathways in liver fibrosis

miRNA-seq provides novel insight into the response to hyper- and hypo- salinity acclimation in Crassostrea hongkongensis

The Hong Kong oyster, Crassostrea hongkongensis, is a significant bivalve species with economic importance. It primarily inhabits the estuarine intertidal zones in southern China, making it susceptible to salinity fluctuations. Consequently, investigating the molecular mechanisms governing salinity regulation in C. hongkongensis is essential. In this study, we conducted miRNA-seq on C. hongkongensis to compare miRNA expression differences under varying salinities (5‰, 25‰, and 35‰). The miRNA sequencing revealed 51 known miRNAs and 95 novel miRNAs across nine small RNA libraries (S5, S25, and S35). Among these miRNAs, we identified 6 down-regulated differentially expressed (DE) miRNAs in response to hypo-salinity stress (5‰), while 1 up-regulated DE miRNA and 5 down-regulated DE miRNAs were associated with hyper-salinity stress (35‰). Additionally, we predicted 931 and 768 potential target genes for hypo- and hyper-salinity stress, respectively. Functional gene annotation indicated that the target genes under hypo-salinity stress were linked to vesicle-mediated transport and metal ion binding. Conversely, those under hyper-salinity stress were primarily involved in signal transduction and metabolic processes. These findings have provided insights into the regulatory role of miRNAs, their potential target genes and associated pathways in oyster hypo- and hyper-salinity stress, which establish a foundation for future studies on the roles of miRNAs in salinity acclimation mechanisms in C. hongkongensis.

Human umbilical cord-derived mesenchymal stem cells attenuate hepatic stellate cells activation and liver fibrosis

BACKGROUND

Liver cirrhosis, a prevalent chronic liver disease, is characterized by liver fibrosis as its central pathological process. Recent advancements highlight the clinical efficacy of umbilical cord mesenchymal stem cell (UC-MSC) therapy in the treatment of liver cirrhosis.

METHODS AND RESULTS

We investigated the pharmacodynamic effects of UC-MSCs and MSC conditional medium (MSC-CM) in vivo, utilizing a carbon tetrachloride (CCl4)-induced fibrotic rat model. Concurrently, we assessed the in vitro impact of MSCs and MSC-CM on various cellular process of hepatic stellate cells (HSCs), including proliferation, apoptosis, activation, immunomodulatory capabilities, and inflammatory factor secretion. Our results indicate that both MSCs and MSC-CM significantly ameliorate the pathological extent of fibrosis in animal tissues, reducing the collagen content, serum biochemical indices and fibrosis biomarkers. In vitro, MSC-CM significantly inhibited the activation of the HSC line LX-2. Notably, MSC-CM modulated the expression of type I procollagen and TGFβ-1 while increasing MMP1 expression. This modulation restored the MMP1/TIMP1 ratio imbalance and extracellular matrix deposition in TGFβ-1 induced fibrosis. Both MSCs and MSC-CM not only induced apoptosis in HSCs but also suppressed proliferation and inflammatory cytokine release from activated HSCs. Furthermore, MSCs and MSC-CM exerted a suppressive effect on total lymphocyte activation.

CONCLUSIONS

UC-MSCs and MSC-CM primarily modulate liver fibrosis severity by regulating HSC activation. This study provides both in vivo and in vitro pharmacodynamic evidence supporting the use of MSCs in liver fibrosis treatment.

A detailed overview of quercetin: implications for cell death and liver fibrosis mechanisms

Background

Quercetin, a widespread polyphenolic flavonoid, is known for its extensive health benefits and is commonly found in the plant kingdom. The natural occurrence and extraction methods of quercetin are crucial due to its bioactive potential.

Purpose

This review aims to comprehensively cover the natural sources of quercetin, its extraction methods, bioavailability, pharmacokinetics, and its role in various cell death pathways and liver fibrosis.

Methods

A comprehensive literature search was performed across several electronic databases, including PubMed, Embase, CNKI, Wanfang database, and ClinicalTrials.gov, up to 10 February 2024. The search terms employed were "quercetin", "natural sources of quercetin", "quercetin extraction methods", "bioavailability of quercetin", "pharmacokinetics of quercetin", "cell death pathways", "apoptosis", "autophagy", "pyroptosis", "necroptosis", "ferroptosis", "cuproptosis", "liver fibrosis", and "hepatic stellate cells". These keywords were interconnected using AND/OR as necessary. The search focused on studies that detailed the bioavailability and pharmacokinetics of quercetin, its role in different cell death pathways, and its effects on liver fibrosis.

Results

This review details quercetin's involvement in various cell death pathways, including apoptosis, autophagy, pyroptosis, necroptosis, ferroptosis, and cuproptosis, with particular attention to its regulatory influence on apoptosis and autophagy. It dissects the mechanisms through which quercetin affects these pathways across different cell types and dosages. Moreover, the paper delves into quercetin's effects on liver fibrosis, its interactions with hepatic stellate cells, and its modulation of pertinent signaling cascades. Additionally, it articulates from a physical organic chemistry standpoint the uniqueness of quercetin's structure and its potential for specific actions in the liver.

Conclusion

The paper provides a detailed analysis of quercetin, suggesting its significant role in modulating cell death mechanisms and mitigating liver fibrosis, underscoring its therapeutic potential.

Crosstalk of lysyl oxidase-like 1 and lysyl oxidase prolongs their half-lives and regulates liver fibrosis through Notch signal

BACKGROUND

Lysyl oxidase (LOX) family members (LOX and LOXL1 to 4) are crucial copper-dependent enzymes responsible for cross-linking collagen and elastin. Previous studies have revealed that LOX and LOXL1 are the most dramatically dysregulated LOX isoforms during liver fibrosis. However, the crosstalk between them and the underlying mechanisms involved in the profibrotic behaviors of HSCs, as well as the progression of liver fibrosis, remain unclear.

METHODS

pCol9GFP-HS4,5Tg mice, Loxl1fl/flGfapCre mice, human HSC line, and primary HSCs were enrolled to study the dysregulation pattern, profibrotic roles, and the potential mechanisms of LOX and LOXL1 interaction involved in the myofibroblast-like transition of HSCs and liver fibrogenesis.

RESULTS

LOX and LOXL1 were synergistically upregulated during liver fibrogenesis, irrespective of etiology, together orchestrating the profibrotic behaviors of HSCs. LOX and LOXL1 coregulated in HSCs, whereas LOXL1 dominated in the coregulation loop. Interestingly, the interaction between LOXL1 and LOX prolonged their half-lives, specifically enhancing the Notch signal-mediated myofibroblast-like transition of HSCs. Selective disruption of Loxl1 in Gfap+ HSCs deactivated the Notch signal, inhibited HSC activation, and relieved carbon tetrachloride-induced liver fibrosis.

CONCLUSIONS

Our current study confirmed the synergistic roles and the underlying mechanisms of LOXL1 and LOX crosstalk in the profibrotic behaviors of HSCs and liver fibrosis progression, providing experimental evidence for further clear mechanism-based anti-LOXL1 strategy development in the therapy of liver fibrosis.

Mi-BMSCs alleviate inflammation and fibrosis in CCl4-and TAA-induced liver cirrhosis by inhibiting TGF-β/Smad signaling

Cirrhosis is an aggressive disease, and over 80 % of liver cancer patients are complicated by cirrhosis, which lacks effective therapies. Transplantation of mesenchymal stem cells (MSCs) is a promising option for treating liver cirrhosis. However, this therapeutic approach is often challenged by the low homing ability and short survival time of transplanted MSCs in vivo. Therefore, a novel and efficient cell delivery system for MSCs is urgently required. This new system can effectively extend the persistence and duration of MSCs in vivo. In this study, we present novel porous microspheres with microfluidic electrospray technology for the encapsulation of bone marrow-derived MSCs (BMSCs) in the treatment of liver cirrhosis. Porous microspheres loaded with BMSCs (Mi-BMSCs) exhibit good biocompatibility and demonstrate better anti-inflammatory properties than BMSCs alone. Mi-BMSCs significantly increase the duration of BMSCs and exert potent anti-inflammatory and anti-fibrosis effects against CCl4 and TAA-induced liver cirrhosis by targeting the TGF-β/Smad signaling pathway to ameliorate cirrhosis, which highlight the potential of Mi-BMSCs as a promising therapeutic approach for early liver cirrhosis.

miR-541 is associated with the prognosis of liver cirrhosis and directly targets JAG2 to inhibit the activation of hepatic stellate cells

BACKGROUND

The activation of hepatic stellate cells (HSCs) has been emphasized as a leading event of the pathogenesis of liver cirrhosis, while the exact mechanism of its activation is largely unknown. Furthermore, the novel non-invasive predictors of prognosis in cirrhotic patients warrant more exploration. miR-541 has been identified as a tumor suppressor in hepatocellular carcinoma and a regulator of fibrotic disease, such as lung fibrosis and renal fibrosis. However, its role in liver cirrhosis has not been reported.

METHODS

Real-time PCR was used to detect miR-541 expression in the liver tissues and sera of liver cirrhosis patients and in the human LX-2. Gain- and loss-of-function assays were performed to evaluate the effects of miR-541 on the activation of LX-2. Bioinformatics analysis and a luciferase reporter assay were conducted to investigate the target gene of miR-541.

RESULTS

miR-541 was downregulated in the tissues and sera of patients with liver cirrhosis, which was exacerbated by deteriorating disease severity. Importantly, the lower expression of miR-541 was associated with more episodes of complications including ascites and hepatic encephalopathy, a shorter overall lifespan, and decompensation-free survival. Moreover, multivariate Cox's regression analysis verified lower serum miR-541 as an independent risk factor for liver-related death in cirrhotic patients (HR = 0.394; 95% CI: 0.164-0.947; P = 0.037). miR-541 was also decreased in LX-2 cells activated by TGF-β and the overexpression of miR-541 inhibited the proliferation, activation and hydroxyproline secretion of LX-2 cells. JAG2 is an important ligand of Notch signaling and was identified as a direct target gene of miR-541. The expression of JAG2 was upregulated in the liver tissues of cirrhotic patients and was inversely correlated with miR-541 levels. A rescue assay further confirmed that JAG2 was involved in the function of miR-541 when regulating LX-2 activation and Notch signaling.

CONCLUSIONS

Dysregulation of miR-541/JAG2 axis might be a as a new mechanism of liver fibrosis, and miR-541 could serve as a novel non-invasive biomarker and therapeutic targets for liver cirrhosis.

The Effect of Boric Acid and Sodium Pentaborate Pentahydrate-Treated Foreskin Derived Mesenchymal Stem Cells on Liver Fibrosis

Liver fibrosis is a worldwide public health problem due to its life-threatening complications, including portal hypertension, liver failure, cirrhosis, and hepatocellular carcinoma (HCC). Liver fibrosis is the net result of a complex excessive accumulation of extracellular matrix (ECM). Activation of hepatic stellate cells (HSCs) are the cause of deposition of ECM and are commonly recognized as a key step in liver fibrosis. The aim of this study was to investigate the effect of foreskin-derived mesenchymal stem cells treated with boron compounds on liver fibrosis. Rats were injected intraperitoneally with thioacetamide (TAA) at a dose of 150 mg/kg except sham and control groups' rats. Thioacetamide (TAA), foreskin-derived mesenchymal stem cells (TAA + FSDMSC), FSDMSC treated with boric acid (TAA + FSDMSC + BA), FSDMSC treated with sodium pentaborate pentahydrate (TAA + FSDMSC + NaB), control and sham groups were studied. Boron compound treated foreskin-derived mesenchymal stem cells were injected into the tail vein, and evaluations were conducted after 4 weeks and liver tissues were obtained for structural, immunohistochemical, and western blot studies and blood samples were taken for biochemical analysis. FSDMSC (BA) alleviates TAA-induced rats liver fibrosis, and BA showed a positive effect on foreskin-derived mesenchymal stem cells viability. After using BA-treated mesenchymal stem cells, we observed that there was regression in the fibrotic areas at TAA-induced liver fibrosis. The result demonstrates that the contribution of TAA + FSDMSC and TAA + FSDMSC (NaB) at the level of structure is not effective in regression of fibrosis in TAA-generated liver fibrosis. We concluded that FSDMSC treated with BA may be a factor in the regression of fibrosis.

New therapeutic approaches against pulmonary fibrosis

Pulmonary fibrosis is the end-stage change of a large class of lung diseases characterized by the proliferation of fibroblasts and the accumulation of a large amount of extracellular matrix, accompanied by inflammatory damage and tissue structure destruction, which also shows the normal alveolar tissue is damaged and then abnormally repaired resulting in structural abnormalities (scarring). Pulmonary fibrosis has a serious impact on the respiratory function of the human body, and the clinical manifestation is progressive dyspnea. The incidence of pulmonary fibrosis-related diseases is increasing year by year, and no curative drugs have appeared so far. Nevertheless, research on pulmonary fibrosis have also increased in recent years, but there are no breakthrough results. Pathological changes of pulmonary fibrosis appear in the lungs of patients with coronavirus disease 2019 (COVID-19) that have not yet ended, and whether to improve the condition of patients with COVID-19 by means of the anti-fibrosis therapy, which are the questions we need to address now. This review systematically sheds light on the current state of research on fibrosis from multiple perspectives, hoping to provide some references for design and optimization of subsequent drugs and the selection of anti-fibrosis treatment plans and strategies.

Liver fibrosis in fish research: From an immunological perspective

Liver fibrosis is a pathological process whereby the liver is subjected to various acute and chronic injuries, resulting in the activation of hepatic stellate cells (HSCs), an imbalance of extracellular matrix generation and degradation, and deposition in the liver. This review article summarizes the current understanding of liver fibrosis in fish research. Liver fibrosis is a common pathological condition that occurs in fish raised in aquaculture. It is often associated with poor water quality, stressful conditions, and the presence of pathogens. The review describes the pathophysiology of liver fibrosis in fish, including the roles of various cells and molecules involved in the development and progression of the disease. The review also covers the various methods used to diagnose and assess the severity of liver fibrosis in fish, including histological analysis, biochemical markers, and imaging techniques. In addition, the article discusses the current treatment options for liver fibrosis in fish, including dietary interventions, pharmaceuticals, and probiotics. This review highlights the need for more in-depth research in this area to better understand the mechanisms by which liver fibrosis in fish occurs and to develop effective prevention and treatment strategies. Finally, improved management practices and the development of new treatments will be critical to the sustainability of aquaculture and the health of farmed fish.

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.

Molecular mechanism by which the Notch signaling pathway regulates autophagy in a rat model of pulmonary fibrosis in pigeon breeder's lung

This study investigated the molecular mechanisms underlying the involvement of the Notch signaling pathway and autophagy in the development of pulmonary fibrosis in pigeon breeder's lung (PBL). Rats were divided into control (Ctrl), PBL model (M), M + D (Notch signaling inhibition), M + W (autophagy inhibition), and M + R (autophagy induction) groups. Lyophilized protein powder from pigeon shedding materials was used as an allergen to construct a fibrotic PBL rat model. The mechanism by which Notch signaling regulated autophagy in the pulmonary fibrosis of PBL was investigated by inhibiting the Notch pathway and interfering with autophagy. Pulmonary interstitial fibrosis was significantly greater in the M group and the M + W group than in the M + D and M + R groups. The expression of α-smooth muscle actin was significantly higher in the M, M + D, and M + W groups than in the Ctrl group (P < 0.05). The expression of the cell autophagy markers Beclin1 and LC3 was lower in the M, M + D, and M + W groups than in the Ctrl group (P < 0.05), whereas Beclin1 and LC3 expressions were higher in the M + D and M + R groups than in the M group. The levels of reactive oxygen species in serum and lung tissues were higher in the M, M + D, M + W, and M + R groups than in the Ctrl group (P < 0.05). The Notch signaling pathway is involved in the pathological process of pulmonary fibrosis in the rat model of PBL by regulating autophagy.

Intercellular communication among liver cells in the perisinusoidal space of the injured liver: Pathophysiology and therapeutic directions

Hepatic stellate cells (HSCs) in the perisinusoidal space are surrounded by hepatocytes, liver sinusoidal endothelial cells, Kupffer cells, and other resident immune cells. In the normal liver, HSCs communicate with these cells to maintain normal liver functions. However, after chronic liver injury, injured hepatocytes release several proinflammatory mediators, reactive oxygen species, and damage-associated molecular patterns into the perisinusoidal space. Consequently, such alteration activates quiescent HSCs to acquire a myofibroblast-like phenotype and express high amounts of transforming growth factor-β1, angiopoietins, vascular endothelial growth factors, interleukins 6 and 8, fibril forming collagens, laminin, and E-cadherin. These phenotypic and functional transdifferentiation lead to hepatic fibrosis with a typical abnormal extracellular matrix synthesis and disorganization of the perisinusoidal space of the injured liver. Those changes provide a favorable environment that regulates tumor cell proliferation, migration, adhesion, and survival in the perisinusoidal space. Such tumor cells by releasing transforming growth factor-β1 and other cytokines, will, in turn, activate and deeply interact with HSCs via a bidirectional loop. Furthermore, hepatocellular carcinoma-derived mediators convert HSCs and macrophages into protumorigenic cell populations. Thus, the perisinusoidal space serves as a critical hub for activating HSCs and their interactions with other cell types, which cause a variety of liver diseases such as hepatic inflammation, fibrosis, cirrhosis, and their complications, such as portal hypertension and hepatocellular carcinoma. Therefore, targeting the crosstalk between activated HSCs and tumor cells/immune cells in the tumor microenvironment may also support a promising therapeutic strategy.

The double-edged role of hydrogen sulfide in the pathomechanism of multiple liver diseases

In mammalian systems, hydrogen sulfide (H₂S)-one of the three known gaseous signaling molecules in mammals-has been found to have a variety of physiological functions. Existing studies have demonstrated that endogenous H₂S is produced through enzymatic and non-enzymatic pathways. The liver is the body's largest solid organ and is essential for H₂S synthesis and elimination. Mounting evidence suggests H₂S has essential roles in various aspects of liver physiological processes and pathological conditions, such as hepatic lipid metabolism, liver fibrosis, liver ischemia‒reperfusion injury, hepatocellular carcinoma, hepatotoxicity, and acute liver failure. In this review, we discuss the functions and underlying molecular mechanisms of H₂S in multiple liver pathophysiological conditions.

Promising traditional Chinese medicine for the treatment of cholestatic liver disease process (cholestasis, hepatitis, liver fibrosis, liver cirrhosis)

ETHNOPHARMACOLOGICAL RELEVANCE

Cholestatic liver disease (CLD) is mainly characterized by cholestasis. If not treated, it will deteriorate to cholestatic hepatitis, liver fibrosis, liver cirrhosis, and even liver failure. CLD has a high clinical incidence, and limited treatment with single therapy. In the long-term clinical exploration, traditional Chinese medicine (TCM) has been corroborated with unique therapeutic effects on the CLD process.

AIM OF THIS REVIEW

This paper summarizes the effective single and compound TCMs for the treatment of CLD. According to 4 important clinical stages of CLD: cholestasis, hepatitis, liver fibrosis, liver cirrhosis, pharmacological effects and mechanisms of 5 typical TCM examples are reviewed, aims to provide basis for clinical drug selection in different processes of CLD.

MATERIALS AND METHODS

Relevant scientific articles regarding therapeutic effects of TCM for the CLD were collected from different databases. We collated three single herbs including Artemisia scoparia Waldst. et Kit. or Artemisia capillaris Thunb. (Artemisiae Scopariae Herba, Yin Chen in Chinese), Paeonia lactiflora Pall. or Paeonia veitchii Lynch. (Paeoniae radix rubra, Chi Shao in Chinese), Poria cocos (Schw.) Wolf (Poria, Fu Ling in Chinese), and two compound herbs of Huang Qi Decoction (HQD) and Yin Chen Hao Decoction (YCHD) to studied and analyzed.

RESULTS

We proposed five promising TCMs treatments for the important developmental stages of CLD. Among them, Yin Chen is an essential medicine for protecting liver and gallbladder, and its TCM prescription is also a promising strategy for cholestasis. Based on clinical evidence, high-dose application of Chi Shao is a clinical special treatment of cholestasis hepatitis. Fu Ling can regulate immune cells and increase antibody levels in serum, which is expected to be an emerging therapy to prevent cholestatic liver fibrosis to cirrhosis. HQD can be used as routine clinical medicine for liver fibrosis. In addition, YCHD can exert better comprehensive advantages with multiple components, can treat the whole course of CLD and prevent it from developing to the end-stage.

CONCLUSION

Yin Chen, Chi Shao, Fu Ling, HQD and YCHD have shown good clinical efficacy in controlling the development of CLD. Clinically, it is easier to curb the development of CLD by adopting graded diagnosis and treatment measures. We suggest that CLD should be risk stratified in clinical treatment to ensure personalized treatment for patients, so as to slow down the development of the disease.

Overcoming therapeutic resistance to platinum-based drugs by targeting Epithelial–Mesenchymal transition

Platinum-based drugs (PBDs), including cisplatin, carboplatin, and oxaliplatin, have been widely used in clinical practice as mainstay treatments for various types of cancer. Although there is firm evidence of notable achievements with PBDs in the management of cancers, the acquisition of resistance to these agents is still a major challenge to efforts at cure. The introduction of the epithelial-mesenchymal transition (EMT) concept, a critical process during embryonic morphogenesis and carcinoma progression, has offered a mechanistic explanation for the phenotypic switch of cancer cells upon PBD exposure. Accumulating evidence has suggested that carcinoma cells can enter a resistant state via induction of the EMT. In this review, we discussed the underlying mechanism of PBD-induced EMT and the current understanding of its role in cancer drug resistance, with emphasis on how this novel knowledge can be exploited to overcome PBD resistance via EMT-targeted compounds, especially those under clinical trials.

Oxidative stress mediated by the TLR4/NOX2 signalling axis is involved in polystyrene microplastic-induced uterine fibrosis in mice

Microplastics (MPs), as a new environmental pollutant, have received widespread attention worldwide. Uterine fibrosis is one of the main factors of female reproductive disorders. However, it is unclear whether the female reproductive disorders caused by MPs are related to uterine fibrosis. Therefore, in this study, we constructed female mouse models exposed to polystyrene microplastics (PS-MPs). We found that PS-MP exposure resulted in endometrial thinning and severe collagen fibre deposition in female mice. Further mechanistic studies found that PS-MP exposure increased the expression of high mobility group Box 1 (HMGB1) and acetyl-HMGB1, further activating the Toll-like receptor 4/NADPH oxidase 2 (TLR4/NOX2) signalling axis and eventually causing oxidative stress. Afterwards, oxidative stress elicited the activation of Notch and the transforming growth factor β (TGF-β) signalling pathway, leading to increased levels of fibrotic proteins and collagen. Correspondingly, PS-MP treatment upregulated the expression of TLR4 and NOX2 and the level of reactive oxygen species (ROS) and increased the levels of fibrotic protein and collagen in mouse endometrial epithelial cells cultured in vitro. Conversely, inhibition of the TLR4/NOX2 signalling pathway effectively reduced the level of ROS in cells, weakened the upregulation of Notch and TGF-β signalling by PS-MPs, and efficiently reduced the expression of fibrotic and collagen genes. In summary, we demonstrated a new mechanism by which MPs induce uterine fibrosis in mice, that is, by inducing oxidative stress to activate the Notch and TGF-β signalling pathways by triggering the TLR4/NOX2 signalling axis. Targeting TLR4/NOX2 signalling may consequently prove to be an innovative therapeutic option that is effective in alleviating the reproductive toxicity of PS-MPs. Our study sheds new light on the reproductive toxicity of MPs and provides suggestions and references for comparative medicine and clinical medicine.

Mesenchymal stem cell homing to improve therapeutic efficacy in liver disease

Mesenchymal stem cell (MSC) transplantation, as an alternative strategy to orthotopic liver transplantation, has been evaluated for treating end-stage liver disease. Although the therapeutic mechanism of MSC transplantation remains unclear, accumulating evidence has demonstrated that MSCs can regenerate tissues and self-renew to repair the liver through differentiation into hepatocyte-like cells, immune regulation, and anti-fibrotic mechanisms. Multiple clinical trials have confirmed that MSC transplantation restores liver function and alleviates liver damage. A sufficient number of MSCs must be home to the target tissues after administration for successful application. However, inefficient homing of MSCs after systemic administration is a major limitation in MSC therapy. Here, we review the mechanisms and clinical application status of MSCs in the treatment of liver disease and comprehensively summarize the molecular mechanisms of MSC homing, and various strategies for promoting MSC homing to improve the treatment of liver disease.

Macrophage Polarization and Its Role in Liver Disease

Macrophages are important immune cells in innate immunity, and have remarkable heterogeneity and polarization. Under pathological conditions, in addition to the resident macrophages, other macrophages are also recruited to the diseased tissues, and polarize to various phenotypes (mainly M1 and M2) under the stimulation of various factors in the microenvironment, thus playing different roles and functions. Liver diseases are hepatic pathological changes caused by a variety of pathogenic factors (viruses, alcohol, drugs, etc.), including acute liver injury, viral hepatitis, alcoholic liver disease, metabolic-associated fatty liver disease, liver fibrosis, and hepatocellular carcinoma. Recent studies have shown that macrophage polarization plays an important role in the initiation and development of liver diseases. However, because both macrophage polarization and the pathogenesis of liver diseases are complex, the role and mechanism of macrophage polarization in liver diseases need to be further clarified. Therefore, the origin of hepatic macrophages, and the phenotypes and mechanisms of macrophage polarization are reviewed first in this paper. It is found that macrophage polarization involves several molecular mechanisms, mainly including TLR4/NF-κB, JAK/STATs, TGF-β/Smads, PPARγ, Notch, and miRNA signaling pathways. In addition, this paper also expounds the role and mechanism of macrophage polarization in various liver diseases, which aims to provide references for further research of macrophage polarization in liver diseases, contributing to the therapeutic strategy of ameliorating liver diseases by modulating macrophage polarization.

Effect of Hepatocyte Growth Factor-Transfected Human Umbilical Cord Mesenchymal Stem Cells on Hepatic Stellate Cells by Regulating Transforming Growth Factor-β1/Smads Signaling Pathway

Studies have shown that human umbilical cord mesenchymal stem cells (hUCMSCs) could ameliorate liver fibrosis (LF) through inhibiting the activation of hepatic stellate cells (HSCs). However, the specific mechanisms have not been studied clearly. The purpose of this study was to explore the possible mechanism of hepatocyte growth factor (HGF)-transfected hUCMSCs in inhibiting the proliferation and activation of HSCs-T6. The upper and lower double-cell coculture system was established among HGF-hUCMSCs, LV5-NC-hUCMSCs, hUCMSCs, and HSCs-T6 in experimental groups; HSCs-T6 were cultured alone as control group. After coculturing for 1, 2, and 3 days, results showed that HGF-transfected hUCMSCs could decrease cell viability of HSCs-T6 and promote apoptosis; inhibit their activation and reduce the expression of Collagen I, Collagen III, TGF-β1, Smad2 and Smad3, which may be related to inhibiting the activation of TGF-β1/Smads signaling pathway. These findings suggested that HGF-transfected hUCMSCs may be used as an alternative and novel therapeutic approach for the treatment of LF.

The Novel Chinese Medicine JY5 Formula Alleviates Hepatic Fibrosis by Inhibiting the Notch Signaling Pathway

Advanced liver fibrosis can lead to cirrhosis, resulting in an accelerated risk of hepatocellular carcinoma and liver failure. Fuzheng Huayu formula (FZHY) is a traditional Chinese medicine formula treated liver fibrosis in China approved by a Chinese State Food and Drug Administration (NO: Z20050546), composed of Salvia Miltiorrhiza bge., Prunus davidiana (Carr.) Franch., cultured Cordyceps sinensis (BerK.) Sacc. Mycelia, Schisandra chinensis (Turcz.) Baill., Pinus massoniana Lamb., and Gynostemma pentaphyllum (Thunb.) Makino. However, the main active substances and mechanism of FZHY are unclear. The aim of this study is to identify a novel anti-fibrotic compound, which consists of the main active ingredients of FZHY, and investigate its mechanism of pharmacological action. The main active ingredients of FZHY were investigated by quantitative analysis of FZHY extracts and FZHY-treated plasma and liver in rats. The anti-fibrotic composition of the main active ingredients was studied through uniform design in vivo, and its mechanism was evaluated in carbon tetrachloride (CCl₄)- and bile duct ligation (BDL)-induced liver fibrosis models in rats and mice, and transforming growth factor beta 1-induced LX-2 cell activation model in vitro. A novel Chinese medicine, namely JY5 formula, consisting of salvianolic acid B, schisantherin A, and amygdalin, the main active ingredients of FZHY, significantly alleviated hepatic hydroxyproline content and collagen deposition in CCl₄-and BDL-induced fibrotic liver in rats and mice. In addition, JY5 inhibited the activation of hepatic stellate cells (HSCs) by inactivating Notch signaling in vitro and in vivo. In this study, we found a novel JY5 formula, which exerted anti-hepatic fibrotic effects by inhibiting the Notch signaling pathway, consequently suppressing HSCs activation. These results provide an adequate scientific basis for clinical research and application of the JY5 formula, which may be a potential novel therapeutic candidate for liver fibrosis.

NOTCH3 rs1043996 Polymorphism Is Associated with the Occurrence of Alcoholic Liver Cirrhosis Independently of PNPLA3 and TM6SF2 Polymorphisms

Alcoholic liver cirrhosis (ALC) is the most common indication for liver transplantation (LT) in Croatia and presents a risk factor for the development of hepatocellular carcinoma (HCC). However, genetic susceptibility has not yet been systematically studied. We aimed to investigate the contribution of the risk polymorphisms PNPLA3 rs738409, EGF rs4444903, TM6SF2 rs58542926, MTHFR rs1801133, previously identified in other populations and, additionally, the contribution of Notch-related polymorphisms (NOTCH1 rs3124591, NOTCH3 rs1043996 and rs1044116, NOTCH4 rs422951). The study included 401 patients. The ALC group consisted of 260 LT candidates, 128 of whom had histopathologically confirmed HCC, and 132 of whom were without HCC. The control group included 141 patients without liver disease. Genotyping was performed by PCR using Taqman assays. The patients' susceptibility to ALC was significantly associated with PNPLA3 rs738409, TM6SF2 rs58542926, and NOTCH3 rs1043996 polymorphisms. These polymorphisms remained significantly associated with ALC occurrence in a logistic regression model, even after additional model adjustment for sex and age. Cirrhotic patients with the PNPLA3 GG genotype demonstrated higher activity of ALT aminotransferases than patients with CC or CG genotypes. The susceptibility to the development of HCC in ALC was significantly associated with PNPLA3 rs738409 and EGF rs4444903 polymorphisms, and logistic regression confirmed these polymorphisms as independent predictors.

A single-cell atlas of liver metastases of colorectal cancer reveals reprogramming of the tumor microenvironment in response to preoperative chemotherapy

Metastasis is the primary cause of cancer-related mortality in colorectal cancer (CRC) patients. How to improve therapeutic options for patients with metastatic CRC is the core question for CRC treatment. However, the complexity and diversity of stromal context of the tumor microenvironment (TME) in liver metastases of CRC have not been fully understood, and the influence of stromal cells on response to chemotherapy is unclear. Here we performed an in-depth analysis of the transcriptional landscape of primary CRC, matched liver metastases and blood at single-cell resolution, and a systematic examination of transcriptional changes and phenotypic alterations of the TME in response to preoperative chemotherapy (PC). Based on 111,292 single-cell transcriptomes, our study reveals that TME of treatment-naïve tumors is characterized by the higher abundance of less-activated B cells and higher heterogeneity of tumor-associated macrophages (TAMs). By contrast, in tumors treated with PC, we found activation of B cells, lower diversity of TAMs with immature and less activated phenotype, lower abundance of both dysfunctional T cells and ECM-remodeling cancer-associated fibroblasts, and an accumulation of myofibroblasts. Our study provides a foundation for future investigation of the cellular mechanisms underlying liver metastasis of CRC and its response to PC, and opens up new possibilities for the development of therapeutic strategies for CRC.

The ameliorative effect of niclosamide on bile duct ligation induced liver fibrosis via suppression of NOTCH and Wnt pathways

Liver fibrosis is the conjoint consequence of almost all chronic liver diseases. Cholestatic liver injury is a significant stimulus for fibrotic liver. This study was conducted to investigate the hepatoprotective effect of niclosamide as a NOTCH inhibitor and on the Wnt pathway against cholestatic liver fibrosis (CLF) which was experimentally induced by bile duct ligation (BDL). Rats were randomly divided into five main groups (6 per group): sham, BDL, BDL/niclosamide 5, BDL/niclosamide 10 and niclosamide 10 only group. Niclosamide was administered intraperitoneally (i.p.) for 4 weeks starting at the same day of surgery at doses 5 and 10 mg/kg. Liver function, cholestasis, oxidative stress, inflammation, liver fibrosis, NOTCH signaling pathway and Wnt pathway markers were assessed. Niclosamide (5 and 10 mg/kg) significantly reduced liver enzymes levels, oxidative stress, inflammation and phosphorylated signal transducer and activator of transcription3 (p-STAT3). Niclosamide (5 and 10 mg/kg) also significantly reduced NOTCH pathway (Jagged1, NOTCH2, NOTCH3, HES1, SOX9), Wnt pathway (Wnt5B, and Wnt10A), and fibrosis (transforming growth factor-beta1 (TGF-β1), alpha smooth muscle actin (α-SMA) and collagen deposition with more prominent effect of the higher dose 10 mg/kg. So, this study presents nicloamide as a promising antifibrotic agent in CLF through inhibition of NOTCH and Wnt pathways.

The Notch signaling pathway regulates macrophage polarization in liver diseases

The liver is not only the main metabolic site of exogenous compounds and drugs, but also an important immune organ in the human body. When a large number of nonself substances (such as drugs, alcohol, pathogens, microorganisms and their metabolites) enter the liver, they will cause serious liver diseases, including liver fibrosis, liver cirrhosis, liver failure, and hepatocellular carcinoma (HCC). Macrophages are the first line of defense against the invasion of exogenous pathogens and significant cellular components of the innate immune system. Macrophages have strong heterogeneity and plasticity. When different pathogens invade the body, they cause different types of polarization of macrophages through different molecular mechanisms. Notch signaling is considered to be the key regulator of the biological function of macrophages. Activating Notch signaling can regulate the differentiation of macrophages into M1 and play a role in promoting inflammation and antitumor activity, while blocking Notch signaling can polarize macrophages to M2, suppressing inflammation and promoting tumor growth. However, there are few studies on regulation of macrophage polarization by the Notch signaling pathway in liver diseases. Therefore, in this review, we will introduce the role of the Notch signaling pathway in regulating macrophage polarization in liver diseases.

The Application of Mesenchymal Stem Cells in the Treatment of Liver Diseases: Mechanism, Efficacy, and Safety Issues

Mesenchymal stem cell (MSC) transplantation is a novel treatment for liver diseases due to the roles of MSCs in regeneration, fibrosis inhibition and immune regulation. However, the mechanisms are still not completely understood. Despite the significant efficacy of MSC therapy in animal models and preliminary clinical trials, issues remain. The efficacy and safety of MSC-based therapy in the treatment of liver diseases remains a challenging issue that requires more investigation. This article reviews recent studies on the mechanisms of MSCs in liver diseases and the associated challenges and suggests potential future applications.

Regulatory long non-coding RNAs of hepatic stellate cells in liver fibrosis (Review)

Liver fibrosis (LF) is a continuous wound healing process caused by numerous chronic hepatic diseases and poses a major threat to human health. Activation of hepatic stellate cells (HSCs) is a critical event in the development of hepatic fibrosis. Long non-coding RNAs (lncRNAs) that are involved in HSC activation, participate in the development of LF and are likely to be therapeutic targets for LF. In the present review, the cellular signaling pathways of LF with respect to HSCs were discussed. In particular, this present review highlighted the current knowledge on the role of lncRNAs in activating or inhibiting LF, revealing lncRNAs that are likely to be biomarkers or therapeutic targets for LF. Additional studies should be performed to elucidate the potential of lncRNAs in the diagnosis and prognosis of LF and to provide novel therapeutic approaches for the reversion of LF.

Maladaptive regeneration - the reawakening of developmental pathways in NASH and fibrosis

With the rapid expansion of the obesity epidemic, nonalcoholic fatty liver disease is now the most common chronic liver disease, with almost 25% global prevalence. Nonalcoholic fatty liver disease ranges in severity from simple steatosis, a benign 'pre-disease' state, to the liver injury and inflammation that characterize nonalcoholic steatohepatitis (NASH), which in turn predisposes individuals to liver fibrosis. Fibrosis is the major determinant of clinical outcomes in patients with NASH and is associated with increased risks of cirrhosis and hepatocellular carcinoma. NASH has no approved therapies, and liver fibrosis shows poor response to existing pharmacotherapy, in part due to an incomplete understanding of the underlying pathophysiology. Patient and mouse data have shown that NASH is associated with the activation of developmental pathways: Notch, Hedgehog and Hippo-YAP-TAZ. Although these evolutionarily conserved fundamental signals are known to determine liver morphogenesis during development, new data have shown a coordinated and causal role for these pathways in the liver injury response, which becomes maladaptive during obesity-associated chronic liver disease. In this Review, we discuss the aetiology of this reactivation of developmental pathways and review the cell-autonomous and cell-non-autonomous mechanisms by which developmental pathways influence disease progression. Finally, we discuss the potential prognostic and therapeutic implications of these data for NASH and liver fibrosis.

Hawthorn Herbal Preparation from Crataegus oxyacantha Attenuates In Vivo Carbon Tetrachloride -Induced Hepatic Fibrosis via Modulating Oxidative Stress and Inflammation

Hawthorn (HAW) is a herbal preparation extracted from Crataegus oxyacantha. HAW has cardioprotective, antioxidants, anti-inflammatory, and anti-hypotensive effects. HAW’s effect on hepatic fibrosis remains, however, unknown. This study evaluated the impact of HAW on carbon tetrachloride (CCl4)-induced hepatic fibrosis in rats and elucidated its mechanisms. HAW reduced liver index and the serum liver enzyme markers and reduced liver damage, and fibrosis as confirmed by histopathological scoring of hematoxylin-eosin staining. Collagen deposition was reduced in HAW group compared to CCl4 group as confirmed by Masson staining, hydroxyproline content, and both mRNA and protein levels of alpha-smooth muscle actin, collagen 1 and 3. HAW also down regulated the gene expressions of inflammatory markers including interleukin-IL-1β, tumor necrosis factor-α, transforming growth factor-β 1, nuclear factor kappa-B, and cyclooxygenase-2 and decreased the myeloperoxidase activity. The effects of HAW was also associated with decreased levels of hepatic oxidative stress markers (malondialdehyde and P.Carbonyl) and with increased activity of superoxide dismutase. Those effects are possibly mediated by blocking the pro-oxidant machinery and down regulating the inflammatory and profibrotic responses. Finally, chlorogenic acid, epicatechin, rutin, vitexin quercetin, and iso quercetin were identified as the major species of polyphenols of the HAW herbal preparation used here. Therefore, HAW’s potent protecting effects against liver fibrosis predicts a significant beneficial application.

Astragaloside IV Synergizes with Ferulic Acid to Alleviate Hepatic Fibrosis in Bile Duct-Ligated Cirrhotic Rats

BACKGROUND

Due to the multi-factorial etiology of hepatic fibrosis, multi-target therapeutics based on combinatory drugs is known to be a promising strategy for the disease.

AIMS

The present study attempted to test the hypothesis that astragaloside IV combined with ferulic acid synergistically inhibits activation of hepatic stellate cells in vivo.

METHODS

Bile duct-ligated rats were treated with astragaloside IV or/and ferulic acid for 28 days. Liver fibrosis was measured by histological examination. The oxidative stress-related biomarkers were measured with spectrophotometry. Expressions of mRNA and protein were measured by real-time PCR and Western blotting.

RESULTS

Bile duct-ligated rat treatment with astragaloside IV and ferulic acid in combination resulted in synergistic alleviation of hepatic fibrosis. Simultaneously, activation of hepatic stellate cells was significantly inhibited by the combination therapy when compared with astragaloside IV or ferulic acid alone. Interestingly, astragaloside IV, but not ferulic acid, induced accumulation of Nrf2 in the nucleus, synthesized antioxidant enzymes through negative regulation of glycogen synthase kinase-3β, scavenged reactive oxygen species, and, in turn, suppressed hepatic stellate cells activation in bile duct-ligated rats. Conversely, ferulic acid, but not astragaloside IV, suppressed TGF-β1 and its receptors expression, which resulted in downregulation of Smad3 and Smad4.

CONCLUSIONS

These findings suggest that the combination of astragaloside IV and ferulic acid synergistically induces deactivation of hepatic stellate cells through inhibition of the TGF-β pathway and activation of the Nrf2 pathway, and suggest that combination of astragaloside IV and ferulic acid is a promising candidate for the treatment of hepatic fibrosis.

Malvidin induces hepatic stellate cell apoptosis via the endoplasmic reticulum stress pathway and mitochondrial pathway

Blueberries have great beneficial effects due to high level of anthocyanins, especially malvidin. Hepatic stellate cells (HSCs) can be activated and increase excessive extracellular matrix (ECM) components, which play a central role in liver fibrogenesis. Therefore, activated HSC's apoptosis can be induced to recover liver fibrosis. Malvidin's effects on apoptosis in rat activated hepatic stellate T6 cells (HSC-T6) in vitro were investigated here. High concentration of malvidin was found to significantly induce apoptosis, activate caspase-3, increase malondialdehyde, upregulate Bax, but downregulate Bcl-2. Moreover, malvidin upregulated the protein levels of some endoplasmic reticulum stress (ERS)-typical markers, including caspase-12, glucose-regulated protein 78 (GRP78), and CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP), suggesting that malvidin induced HSC apoptosis by the ERS apoptosis pathway as well as the mitochondrial-dependent pathway. These findings indicated that blueberry anthocyanins, especially malvidin, could induce activated hepatic stellate cell apoptosis and might act as one kind of functional food ingredient or a novel nutraceutical beneficial for liver health.

Matrine promotes hepatic oval cells differentiation into hepatocytes and alleviates liver injury by suppression of Notch signalling pathway

AIMS

Recent studies have shown that the hyperactive Notch pathway is involved in cirrhosis and hepatocellular carcinoma (HCC) development by regulating differentiation of hepatic oval cells (HOCs) into cancer cells. The aim of this study was to investigate whether matrine can alleviate liver injury and promote HOC differentiation into hepatocytes by suppression of Notch pathway.

MAIN METHODS

We evaluated the expression of Notch-1, Jagged-1, and Hes-1 in HCC tissue by immunohistochemistry. Stem cell characteristics of HOCs were evaluated by CCK-8, cell cycle, and apoptosis. The expression of Notch pathway, HOC markers and albumin (ALB) was detected by immunohistochemistry, QRT-PCR and western blotting. The effects of matrine in protecting liver in vivo were investigated in a rat Solt-Farber precancerous model.

KEY FINDINGS

We found an abnormal activated Notch pathway in HCC tissue, and the hyperactive Notch pathway was strongly associated with poor liver function in patients with cirrhosis with HCC. Using siNotch-1 to inhibit Notch pathway confirmed that Notch pathway could maintain stem cell characteristics of HOCs. Matrine inhibited stem cell characteristics of HOCs, the expression of Notch pathway and HOC markers but upregulated ALB. Matrine in combined with siNotch-1 RNA decreased the more potently inhibited HOC markers and Notch pathway. In rat Solt-Farber precancerous model, prophylactic application of matrine alleviated liver injury, downregulated Notch pathway and HOC markers, and upregulated ALB in a dose-dependent manner.

SIGNIFICANCE

Matrine could promote the differentiation of HOCs into hepatocytes by inhibiting the Notch signalling pathway and alleviate liver injury.

Single-cell technologies in hepatology: new insights into liver biology and disease pathogenesis

Liver disease is a major global health-care problem, affecting an estimated 844 million people worldwide. Despite this substantial burden, therapeutic options for liver disease remain limited, in part owing to a paucity of detailed analyses defining the cellular and molecular mechanisms that drive these conditions in humans. Single-cell transcriptomic technologies are transforming our understanding of cellular diversity and function in health and disease. In this Review, we discuss how these technologies have been applied in hepatology, advancing our understanding of cellular heterogeneity and providing novel insights into fundamental liver biology such as the metabolic zonation of hepatocytes, endothelial cells and hepatic stellate cells, and the cellular mechanisms underpinning liver regeneration. Application of these methodologies is also uncovering critical pathophysiological changes driving disease states such as hepatic fibrosis, where distinct populations of macrophages, endothelial cells and mesenchymal cells reside within a spatially distinct fibrotic niche and interact to promote scar formation. In addition, single-cell approaches are starting to dissect key cellular and molecular functions in liver cancer. In the near future, new techniques such as spatial transcriptomics and multiomic approaches will further deepen our understanding of disease pathogenesis, enabling the identification of novel therapeutic targets for patients across the spectrum of liver diseases.

La plasticidad del hepatocito y su relevancia en la fisiología y la patología hepática

El hígado es uno de los principales órganos encargados de mantener la homeostasis en vertebrados,  además de poseer una gran capacidad regenerativa. El hígado está constituido por diversos tipos celulares que de forma coordinada contribuyen para que el órgano funcione eficientemente. Los hepatocitos representan el tipo celular principal de este órgano y llevan a cabo la mayoría de sus actividades; además, constituyen una población heterogénea de células epiteliales con funciones especializadas en el metabolismo. El fenotipo de los hepatocitos está controlado por diferentes vías de señalización, como la vía del TGFβ/Smads, la ruta Hippo/YAP-TAZ y la vía Wnt/β-catenina, entre otras. Los hepatocitos son células que se encuentran normalmente en un estado quiescente, aunque cuentan con una plasticidad intrínseca que se manifiesta en respuesta a diversos daños en el hígado; así, estas células reactivan su capacidad proliferativa o cambian su fenotipo a través de procesos celulares como la transdiferenciación o la transformación, para contribuir a mantener la homeostasis del órgano en condiciones saludables o desarrollar diversas  patologías.

Implications of hydrogen sulfide in liver pathophysiology: Mechanistic insights and therapeutic potential

Background

Over the last several decades, hydrogen sulfide (H₂S) has been found to exert multiple physiological functions in mammal systems. The endogenous production of H₂S is primarily mediated by cystathione β-synthase (CBS), cystathione γ-lyase (CSE), and 3-mercaptopyruvate sulfurtransferase (3-MST). These enzymes are widely expressed in the liver tissues and regulate hepatic functions by acting on various molecular targets.

Aim of Review

In the present review, we will highlight the recent advancements in the cellular events triggered by H₂S under liver diseases. The therapeutic effects of H₂S donors on hepatic diseases will also be discussed.

Key Scientific Concepts of Review

As a critical regulator of liver functions, H₂S is critically involved in the etiology of various liver disorders, such as nonalcoholic steatohepatitis (NASH), hepatic fibrosis, hepatic ischemia/reperfusion (IR) injury, and liver cancer. Targeting H₂S-producing enzymes may be a promising strategy for managing hepatic disorders.

The role of microRNAs in the pathogenesis, grading and treatment of hepatic fibrosis in schistosomiasis

Schistosomiasis is a prevalent parasitic disease worldwide. The main pathological changes of hepatosplenic schistosomiasis are hepatic granuloma and fibrosis due to worm eggs. Portal hypertension and ascites induced by hepatic fibrosis are usually the main causes of death in patients with chronic hepatosplenic schistosomiasis. Currently, no effective vaccine exists for preventing schistosome infections. For quite a long time, praziquantel (PZQ) was widely used for the treatment of schistosomiasis and has shown benefit in treating liver fibrosis. However, drug resistance and chemical toxicity from PZQ are being increasingly reported in recent years; therefore, new and effective strategies for treating schistosomiasis-induced hepatic fibrosis are urgently needed. MicroRNA (miRNA), a non-coding RNA, has been proved to be associated with the development of many human diseases, including schistosomiasis. In this review, we present a balanced and comprehensive view of the role of miRNAs in the pathogenesis, grading, and treatment of schistosomiasis-associated hepatic fibrosis. The multiple regulatory roles of miRNAs, such as promoting or inhibiting the development of liver pathology in murine schistosomiasis are also discussed in depth. Additionally, miRNAs may serve as candidate biomarkers for diagnosing liver pathology of schistosomiasis and as novel therapeutic targets for treating schistosomiasis-associated hepatic fibrosis.

Reconstruction and analysis of competitive endogenous RNA network reveals regulatory role of long non‑coding RNAs in hepatic fibrosis

Hepatic fibrosis (HF), one of the leading global health problems, is defined as aberrant and excess production of extracellular matrix components. The pathogenesis of HF is complex and poorly understood. Long non‑coding RNAs (LncRNAs) can interact with microRNAs (miRNAs) as competing endogenous RNAs (ceRNAs) to regulate the expression of target genes, which play a significant role in the initiation and progression of HF. In the present study, the LncRNA‑associated ceRNA network was reconstructed based on LncRNA, miRNA and mRNA expression profiles that were downloaded from National Center for Biotechnology Information Gene Expression Omnibus. Bioinformatics assessments including Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed with Database for Annotation, Visualization and Integration Discovery. The ceRNA network was composed of 220 LncRNA nodes, 24 miRNA nodes, 164 mRNA nodes and 1,149 edges. Functional assays identified that a total of 338 GO terms and 25 pathways, including regulation of cytokine and collagen, and the transforming growth factor‑β and Toll‑like receptor signaling pathways, were significantly enriched. In addition, 4 LncRNAs (NONMMUT036242, XR_877072, XR_378619 and XR_378418) were highly related to HF and thereby chosen as key LncRNAs. The present study uncovered a ceRNA network that could further the understanding of the mechanisms underlying HF development and provide potential novel markers for clinical diagnosis and targets for treatment.

Matrine prevents the early development of hepatocellular carcinoma like lesions in rat liver

Matrine (C15H24N2O) is an alkaloid extracted from the Chinese herb Sophora flavescens that has anti-fibrotic and anti-cancer properties. The aim of the present study was to determine the chemopreventive effect of matrine on the development of primary hepatocellular carcinoma (HCC) and its possible association with the suppression of the Notch signaling pathway. The rats were randomly divided into four groups: Control, model, low-dose matrine and high-dose matrine groups. The model was established by combining a partial hepatectomy with diethylnitrosamine (DEN) + 2-acetylaminofluorene (2-AAF). Low- and high-dose matrine groups received intragastric administration of matrine (0.25 and 2.5 g/l of matrine, respectively). DEN + 2-AAF injections and hepatectomy were not performed in the control group. All rats were sacrificed 2, 4 and 7 weeks after hepatectomy. HCC-like histopathological lesions were detected using hematoxylin and eosin staining. The expression levels of α-1-fetoprotein (AFP), albumin (ALB), Notch1 and Hes1 were analyzed using immunohistochemistry. Hepatic lobule structure loss, liver tissue necrosis and inflammatory cell infiltration, and edema degeneration were observed in the model group. By contrast, hepatocyte cord structure was restored and hepatocyte edema degeneration was significantly reduced after 7 weeks of treatment with matrine. In addition, compared with the model group, matrine reduced the expression of AFP, increased the expression of ALB and reduced the expression of Notch1 and Hes1 (only for high-dose matrine; all P<0.05). The findings suggested that matrine could prevent the early development of HCC-like lesions in a rat model, possibly by modulating Notch pathway activation.

Research progress on the anti-hepatic fibrosis action and mechanism of natural products

Hepatic fibrosis is the most common pathological feature of most chronic liver diseases, and its continuous deterioration gradually develops into liver cirrhosis and eventually leads to liver cancer. At present, there are many kinds of drugs used to treat liver fibrosis. However, Western drugs tend to only target single genes/proteins and induce many adverse reactions. Most of the mechanisms and active ingredients of traditional Chinese medicine (TCM) are not clear, and there is a lack of unified diagnosis and treatment standards. Natural products, which are characterized by structural diversity, low toxicity, and origination from a wide range of sources, have unique advantages and great potential in anti-liver fibrosis. This article summarizes the work done over the previous decade, on the active ingredients in natural products that are reported to have anti-hepatic fibrosis effects. The effective anti-hepatic fibrosis ingredients identified can be generally divided into flavonoids, saponins, polysaccharides and alkaloids. Mechanisms of anti-liver fibrosis include inhibition of liver inflammation, anti-lipid peroxidation injury, inhibition of the activation and proliferation of hepatic stellate cells (HSCs), modulation of the synthesis and secretion of pro-fibrosis factors, and regulation of the synthesis and degradation of the extracellular matrix (ECM). This review provides suggestions for the development of anti-hepatic fibrosis drugs.

Delta-like ligand 4/DLL4 regulates the capillarization of liver sinusoidal endothelial cell and liver fibrogenesis

Liver sinusoidal endothelial cells (LSECs) undergo capillarization, or loss of fenestrae, and produce basement membrane during liver fibrotic progression. DLL4, a ligand of the Notch signaling pathway, is predominantly expressed in endothelial cells and maintains liver sinusoidal homeostasis. The aim of this study was to explore the role of DLL4 in LSEC capillarization. The expression levels of DLL4 and the related genes, capillarization markers and basement membrane proteins were assessed by immunohistochemistry, immunofluorescence, RT-PCR and immunoblotting as appropriate. Fenestrae and basement membrane formation were examined by electron microscopy. We found DLL4 was up-regulated in the LSECs of human and CCl4-induced murine fibrotic liver, consistent with LSEC capillarization and liver fibrosis. Primary murine LSECs also underwent capillarization in vitro, with concomitant DLL4 overexpression. Bioinformatics analysis confirmed that DLL4 induced the production of basement membrane proteins in LSECs, which were also increased in the LSECs from 4 and 6-week CCl4-treated mice. DLL4 overexpression also increased the coverage of liver sinusoids by hepatic stellate cells (HSCs) through endothelin-1 (ET-1) synthesis. The hypoxic conditions that was instrumental in driving DLL4 overexpression in the LSECs. Consistent with the above findings, DLL4 silencing in vivo alleviated LSEC capillarization and CCl4-induced liver fibrosis. In conclusion, DLL4 mediates LSEC capillarization and the vicious circle between fibrosis and pathological sinusoidal remodeling.

Overexpression of miRNA-25-3p inhibits Notch1 signaling and TGF-β-induced collagen expression in hepatic stellate cells

During chronic liver injury hepatic stellate cells (HSCs), the principal source of extracellular matrix in the fibrotic liver, transdifferentiate into pro-fibrotic myofibroblast-like cells - a process potentially regulated by microRNAs (miRNAs). Recently, we found serum miRNA-25-3p (miR-25) levels were upregulated in children with Cystic Fibrosis (CF) without liver disease, compared to children with CF-associated liver disease and healthy individuals. Here we examine the role of miR-25 in HSC biology. MiR-25 was detected in the human HSC cell line LX-2 and in primary murine HSCs, and increased with culture-induced activation. Transient overexpression of miR-25 inhibited TGF-β and its type 1 receptor (TGFBR1) mRNA expression, TGF-β-induced Smad2 phosphorylation and subsequent collagen1α1 induction in LX-2 cells. Pull-down experiments with biotinylated miR-25 revealed Notch signaling (co-)activators ADAM-17 and FKBP14 as miR-25 targets in HSCs. NanoString analysis confirmed miR-25 regulation of Notch- and Wnt-signaling pathways. Expression of Notch signaling pathway components and endogenous Notch1 signaling was downregulated in miR-25 overexpressing LX-2 cells, as were components of Wnt signaling such as Wnt5a. We propose that miR-25 acts as a negative feedback anti-fibrotic control during HSC activation by reducing the reactivity of HSCs to TGF-β-induced collagen expression and modulating the cross-talk between Notch, Wnt and TGF-β signaling.

Dynamic Changes of the Aspartate Aminotransferase-to-Platelet Ratio and Transient Elastography in Predicting a Histologic Response in Patients With Chronic Hepatitis B After Entecavir Treatment

OBJECTIVES

To evaluate the dynamic changes of the aspartate aminotransferase (AST)-to-platelet ratio and transient elastography (FibroScan; Echosens, Paris, France) in predicting a histologic response in patients with chronic hepatitis B (CHB) after entecavir treatment.

METHODS

A total of 148 patients with CHB were enrolled. Patient information was collected. All patients received liver biopsy and FibroScan before and after 96 weeks of entecavir treatment.

RESULTS

Baseline liver biopsy results showed that there were 7 patients without liver fibrosis (fibrosis stage F0; 4.7%), 51 patients with mild liver fibrosis (F1; 34.5%), and 90 patients with advanced liver fibrosis (>F1; 60.9%). The liver stiffness value and AST-to-platelet ratio increased significantly as the METAVIR score of the patients increased from F0 to F4 (P < .001). After antiviral therapy for 96 weeks, the average liver stiffness value measured by FibroScan and the AST-to-platelet ratio showed a significant decrease. When we use a decreased liver stiffness value to predict a histologic response, the area under the receiver operating characteristic curve was 0.70 (95% confidence interval, 0.61-0.79; P < .001), and the sensitivity and specificity were 74.3% and 68.8%, respectively. The decrease of the AST-to-platelet ratio also could predict the histologic response of patients with CHB; the area under the receiver operating characteristic curve was 0.77 (95% confidence interval, 0.69-0.86; P < .001) with sensitivity of 76.2% and specificity of 70.2%. A multivariate analysis indicated that a high hepatitis B virus DNA viral load (odds ratio, 1.44; P = .04) and high METAVIR score (odds ratio, 1.38; P = .02) were independent risk factors for the histologic response.

CONCLUSIONS

Both the AST-to-platelet ratio and FibroScan value can effectively predict a histologic response in patients with CHB during entecavir treatment. Therefore, they can be used to monitor these patients during antiviral treatment to avoid multiple liver biopsies.

Overexpression of Tumor Necrosis Factor-Like Ligand 1 A in Myeloid Cells Aggravates Liver Fibrosis in Mice

Macrophages are the master regulator of the dynamic fibrogenesis-fibrosis resolution paradigm. TNF-like ligand 1 aberrance (TL1A) was found to be able to induce intestinal inflammation and fibrosis. Furthermore, significantly increased TL1A had been detected in liver tissues and mononuclear cells of patients with primary biliary cirrhosis (PBC). This study was to investigate the effect of myeloid cells with constitutive TL1A expression on liver fibrogenesis. We found that TL1A expressions in liver tissues and macrophages were significantly increased in mice with liver fibrosis induced by injection of carbon tetrachloride (CCl₄). TL1A overexpression in myeloid cells induced liver function injury, accelerated the necrosis and apoptosis of hepatocytes, recruited macrophages, and promoted activation of hepatic stellate cells (HSCs) and fibrosis. In vitro results of our study showed that TL1A overexpression in macrophages promoted secretion of platelet-derived growth factor-BB (PDGF-BB), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β). Culturing macrophages with TL1A overexpression could accelerate the activation and proliferation of primary HSCs. These results indicated that constitutive TL1A expression in myeloid cells exacerbated liver fibrosis, probably through macrophage recruitment and secretion of proinflammatory and profibrotic cytokines.

Hydrogen Sulfide as a Novel Regulatory Factor in Liver Health and Disease

Hydrogen sulfide (H₂S), a colorless gas smelling of rotten egg, has long been recognized as a toxic gas and environment pollutant. However, increasing evidence suggests that H₂S acts as a novel gasotransmitter and plays important roles in a variety of physiological and pathological processes in mammals. H₂S is involved in many hepatic functions, including the regulation of oxidative stress, glucose and lipid metabolism, vasculature, mitochondrial function, differentiation, and circadian rhythm. In addition, H₂S contributes to the pathogenesis and treatment of a number of liver diseases, such as hepatic fibrosis, liver cirrhosis, liver cancer, hepatic ischemia/reperfusion injury, nonalcoholic fatty liver disease/nonalcoholic steatohepatitis, hepatotoxicity, and acute liver failure. In this review, the biosynthesis and metabolism of H₂S in the liver are summarized and the role and mechanism of H₂S in liver health and disease are further discussed.

Notch inhibition enhances graft-versus-leukemia while reducing graft-versus-host disease

Graft-versus host disease (GVHD) remains the most significant complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Dissociation of graft versus-leukemia (GVL) activity from GVHD has yet to be achieved. In this study, we used γ-secretase inhibitor (GSIs, DAPT) to inhibit Notch signaling in GVHD and GVL murine model. We found that CD11c⁺CD80⁺ dendritic cells (DCs) were up-regulated but did not enhance GVHD. Regulatory T cells (Tregs) and central memory T cells that express high levels of CD62L and CD44 had an expansion after Notch inhibition. Reduced Tumor Necrosis Factor-α and increased Interferon-γ production were found, which might be ascribed to the expansion of Tregs and central memory T cells, and result in increased sensitivity of tumor cells to cytotoxic T lymphocyte activity. Fas Receptor-Fas Ligand interaction plays a critical role in GVL instead of aGVHD. Fas Ligand expressions were similar in recipients with or without Notch inhibition, suggesting that GVL activity was maintained. We showed that Notch inhibition could enhances GVL while reducing GVHD via modulating host DCs and donor T cell activity, and the production of inflammatory cytokines.

Role of Metabolism in Hepatic Stellate Cell Activation and Fibrogenesis

Activation of hepatic stellate cell (HSC) involves the transition from a quiescent to a proliferative, migratory, and fibrogenic phenotype (i.e., myofibroblast), which is characteristic of liver fibrogenesis. Multiple cellular and molecular signals which contribute to HSC activation have been identified. This review specially focuses on the metabolic changes which impact on HSC activation and fibrogenesis.

Inhibition of Mastermind-like 1 alleviates liver fibrosis induced by carbon tetrachloride in rats

Mastermind-like 1 (MAML1) functions in critical transcriptional coactivation in Notch and Wnt/β-catenin signal pathways, which participate in hepatic fibrosis. This study is aimed to reveal the potential role of MAML1 in liver fibrosis and identify its underlying mechanism. In present research, the enhanced expression of MAML1 was found in the fibrotic liver tissues in carbon tetrachloride (CCl4)-induced hepatic fibrosis in rats, and MAML1 expression increased gradually during the activation of hepatic stellate cells (HSCs) isolated from the normal rat. Further studies showed that blocking MAML1 expression efficiently decreased the expression of α-SMA and collagen I (Col1a1) in HSCs. Interestingly, MAML1 may modulate HSCs activation via interrupting both Notch and Wnt/β-catenin signal transductions, and the inhibition of MAML1 by a recombinant adeno-associated virus type 1 vector carrying shRNA targeting MAML1 alleviated CCl4-induced hepatic fibrosis in rats. These findings suggest that the selective regulation of MAML1 expression may be a feasible therapeutic approach to reverse liver fibrosis.

Impact statement

Liver fibrosis is a common wound-healing response to all kinds of liver injuries. Hepatic stellate cells (HSCs) activation is the key event during liver fibrogenesis. Thus, the elucidation of mechanisms for regulating HSCs activation is helpful for identifying novel anti-fibrotic targets and strategies. MAML1, an important component of Notch signal, functions in critical transcriptional coactivation in the Notch and Wnt/β-catenin signal pathways. In the present study, we investigated the potential function of MAML1 during hepatic fibrogenesis in rats. Our results demonstrated that MAML1 participates in liver fibrosis through modulating HSCs activation via interrupting both the Notch and Wnt/β-catenin signal transductions. Additionally, the inhibition of MAML1 markedly attenuated CCl4-induced hepatic fibrogenesis in rats. Our results shed a light for the exploitation of a new therapeutic strategy for hepatic fibrosis via targeting MAML1.