Liver fibrosis. Biochem J. 2008;411:1-18. [PMID: 18333835 DOI: 10.1042/bj20071570]

Transformation of macrophages into myofibroblasts in fibrosis-related diseases: emerging biological concepts and potential mechanism

Macrophage-myofibroblast transformation (MMT) transforms macrophages into myofibroblasts in a specific inflammation or injury microenvironment. MMT is an essential biological process in fibrosis-related diseases involving the lung, heart, kidney, liver, skeletal muscle, and other organs and tissues. This process consists of interacting with various cells and molecules and activating different signal transduction pathways. This review deeply discussed the molecular mechanism of MMT, clarified crucial signal pathways, multiple cytokines, and growth factors, and formed a complex regulatory network. Significantly, the critical role of transforming growth factor-β (TGF-β) and its downstream signaling pathways in this process were clarified. Furthermore, we discussed the significance of MMT in physiological and pathological conditions, such as pulmonary fibrosis and cardiac fibrosis. This review provides a new perspective for understanding the interaction between macrophages and myofibroblasts and new strategies and targets for the prevention and treatment of MMT in fibrotic diseases.

Non-invasive in vivo imaging of changes in Collagen III turnover in myocardial fibrosis

Heart failure (HF) affects 64 million people globally with enormous societal and healthcare costs. Myocardial fibrosis, characterised by changes in collagen content drives HF. Despite evidence that collagen type III (COL3) content changes during myocardial fibrosis, in vivo imaging of COL3 has not been achieved. Here, we discovered the first imaging probe that binds to COL3 with high affinity and specificity, by screening candidate peptide-based probes. Characterisation of the probe showed favourable magnetic and biodistribution properties. The probe's potential for in vivo molecular cardiac magnetic resonance imaging was evaluated in a murine model of myocardial infarction. Using the new probe, we were able to map and quantify, previously undetectable, spatiotemporal changes in COL3 after myocardial infarction and monitor response to treatment. This innovative probe provides a promising tool to non-invasively study the unexplored roles of COL3 in cardiac fibrosis and other cardiovascular conditions marked by changes in COL3.

A, Alkhamiss AS, Hamad RS, Abdel-Reheim MA, Ellethy AT, Elsisi HA, Alsharidah M, Elghandour SR, Elnawawy T, Abdelhady R. Hedgehog signaling is a promising target for the treatment of hepatic fibrogenesis: a new management strategy using itraconazole-loaded nanoparticles

Liver fibrosis is a disease with a great global health and economic burden. Existing data highlights itraconazole (ITRCZ) as a potentially effective anti-fibrotic therapy. However, ITRCZ effect is hindered by several limitations, such as poor solubility and bioavailability. This study aimed to formulate and optimize chitosan nanoparticles (Cht NPs) loaded with ITRCZ as a new strategy for managing liver fibrosis. ITRCZ-Cht NPs were optimized utilizing a developed 22 full factorial design. The optimized formula (F3) underwent comprehensive in vitro and in vivo characterization. In vitro assessments revealed that F3 exhibited an entrapment efficiency of 89.65% ± 0.57%, a 169.6 ± 1.77 nm particle size, and a zeta potential of +15.93 ± 0.21 mV. Furthermore, in vitro release studies indicated that the release of ITRCZ from F3 adhered closely to the first-order model, demonstrating a significant enhancement (p-value < 0.05) in cumulative release compared to plain ITRCZ suspension. This formula increased primary hepatocyte survival and decreased LDH activity in vitro. The in vivo evaluation of F3 in a rat model of liver fibrosis revealed improved liver function and structure. ITRCZ-Cht NPs displayed potent antifibrotic effects as revealed by the downregulation of TGF-β, PDGF-BB, and TIMP-1 as well as decreased hydroxyproline content and α-SMA immunoexpression. Anti-inflammatory potential was evident by reduced TNF-α and p65 nuclear translocation. These effects were likely ascribed to the modulation of Hedgehog components SMO, GLI1, and GLI2. These findings theorize ITRCZ-Cht NPs as a promising formulation for treating liver fibrosis. However, further investigations are deemed necessary.

CCL20 and CD8A as potential diagnostic biomarkers for HBV-induced liver fibrosis in chronic hepatitis B

Background

The main cause of the liver fibrosis (LF) remains hepatitis B virus (HBV) infection, especially in China. Histologically, liver fibrosis still occurs progressively in chronic hepatitis B (CHB) patients, even if HBV-DNA is negative or undetectable. The diagnosis of LF is beneficial to control the development of it, also it may promote the reversal of LF. Although liver biopsy is the gold standard of diagnosis in LF at present, it isa traumatic diagnosis. There are no diagnostic biomarkers as yet for the condition. It is badly in need of biomarkers clinically, which is simple to test, minimally invasive, highly specific, and sensitive. Early detection of HBV-LF development is crucial in the prevention, treatment, and prognosis prediction of HBV-LF. Cytokines are closely associated with both immune regulation and inflammation in the progression of hepatitis B virus associated-liver fibrosis (HBV-LF). In this bioinformatic study, we not only analyzed the relationship between HBV-LF and immune infiltration, but also identified key genes to uncover new therapeutic targets.

Objectives

To find potential biomarkers for liver fibrosis in the development of chronic hepatic B patients.

Materials and methods

We obtained two sets of data including CHB/healthy control and CHB/HBV-LF from the Integrated Gene Expression (GEO) database to select for differential expression analysis. Protein-protein interaction (PPI) network was also generated, while key genes and important gene modules involved in the occurrence and development of HBV-LF were identified. These key genes were analyzed by functional enrichment analysis, module analysis, and survival analysis. Furthermore, the relationship between these two diseases and immune infiltration was explored.

Results

Among the identified genes, 150 were individually associated with CHB and healthy control in the differential gene expression (DGE) analysis. While 14 with CHB and HBV-LF. It was also analyzed in the Robust rank aggregation (RRA) analysis, 34 differential genes were further identified by Cytohubba. Among 34 differential genes, two core genes were determined: CCL20 and CD8A. CCL20 was able to predict CHB positivity (area under the receiver operating characteristic curve [AUC-ROC] = 0.883, 95% confidence interval [CI] 0.786-0.963), while HBV-LF positivity ([AUC-ROC] = 0.687, 95% confidence interval [CI] 0.592-0.779). And CD8A was able to predict CHB positivity ([AUC-ROC] = 0.960, 95% confidence interval [CI] 0.915-0.992), while HBV-LF positivity ([AUC-ROC] = 0.773, 95% confidence interval [CI] 0.680-0.856). Relationship between CCL20 gene expression and LF grades was P < 0.05, as well as CD8A.

Conclusion

CCL20 and CD8A were found to be potential biomarkers and therapeutic targets for HBV-LF. It is instructive for research on the progression of LF in HBV patients, suppression of chronic inflammation, and development of molecularly targeted-therapy for HBV-LF.

The application of a novel platform of multiparametric magnetic resonance imaging in a bioenvironmental toxic carbon tetrachloride-induced mouse model of liver fibrosis

The use of multiparametric magnetic resonance imaging (MRI) to distinguish complex histopathological changes in liver fibrosis has not yet been systematically established. The purpose of this study is to gauge the efficacy of a cutting-edge MRI platform for evaluating ecotoxicologically hazardous carbon tetrachloride (CCl4) induced liver fibrosis, while also scrutinizing the relationship between MRI and its histopathological features. Thirty-six mice were randomly divided into 6 groups, each with 6 mice. Control mice received an intraperitoneal injection of olive oil, while the experimental mice received different doses of intraperitoneal injection of CCl4. Both sets underwent this process twice per week over a duration of 5 weeks. MRI measurements encompassed T1WI, T2WI, T1 mapping, T2 mapping, T2* mapping. Liver fibrosis and inflammation were assessed and classified using Metavir and activity scoring systems. CCl4 successfully induced liver fibrosis in mice, showing an increasing extent of liver fibrosis and liver function damage with the increasing dosage of CCl4. Compared with the control group, T1, ΔT1, and T2 in the experimental group were considerably elevated (P < 0.05) than those in the control group. Spearman's correlation showed that the correlation of Native T1 and △T1 with fibrosis (r = 0.712, 0.678) was better than with inflammation (r = 0.688, 0.536). T2 correlation with inflammation (r = 0.803) was superior to fibrosis (r = 0.568). ROC analysis showed that the AUC of Native T1 was highest (0.906), followed by ΔT1 (0.852), while the AUC increased to 0.945 when all relevant MRI parameters were combined. T1 is the most potent MRI parameter for evaluating CCl4-induced liver fibrosis, followed by ΔT1. Meanwhile, T2 may not be suitable for evaluating liver fibrosis but is more suitable for evaluating liver inflammation.

Segmental analysis of liver cirrhosis with different etiologies: a study based on iodine mixed imaging in port-venous phase

BACKGROUND

Computed tomography (CT) in port-venous phase can display the intra-hepatic vessels, and may provide the possibility for segment function evaluation for cirrhosis.

PURPOSE

To assess the value of iodine mixed imaging of dual-source dual-energy CT in port-venous phase in segmental evaluation of liver cirrhosis with different etiologies.

MATERIAL AND METHODS

Patients diagnosed with liver cirrhosis were enrolled. Patients without cirrhosis were included as a control group. Each patient underwent iodine-contrast enhanced multi-phase dual-energy CT scanning. Parameters were analyzed by SPSS, version 22.0, and Medcalc.

RESULTS

In total, 256 patients were investigated, including 114 Child-Pugh A, 51 Child-Pugh B, 41 Child-Pugh C and 50 control patients. Total iodine content (ICt)/body surface area (BSA) in the cirrhosis group was significantly lower than the control group (P < 0.05) and the standardized-iodine parameter (SI) of each segment decreased with cirrhosis progression. In Child-Pugh A and B, SI increased more significantly in the caudal and lateral segment in A (alcholism) than in the V (virus-related) and N (non-alcoholic steatohepatitis) groups (P < 0.001). ICt/BSA showed the best diagnosis power of cirrhosis with an area under the curve of 0.765, sensitivity of 76.0% and specificity of 71.8%.

CONCLUSION

Blood flow compensated in the left lateral and caudal lobe in the early stage of liver cirrhosis. The compensation in alcoholism in the middle and early stages is significantly higher than that of V and N cirrhosis. Iodine mixed imaging in portal phase may provide the possibility of an incremental value in segmented blood flow perfusion and functional evaluation of liver cirrhosis on a morphological basis.

The role of SPARC (secreted protein acidic and rich in cysteine) in the pathogenesis of obesity, type 2 diabetes, and non-alcoholic fatty liver disease

Secreted protein acidic and rich in cysteine (SPARC) is an extracellular matrix glycoprotein with pleiotropic functions, which is expressed in adipose, hepatic, muscular, and pancreatic tissue. Particularly, several studies demonstrated that SPARC is an important player in the context of obesity, diabetes, and fatty liver disease including advanced hepatic fibrosis and hepatocellular carcinoma. Evidence in murine and human samples indicates that SPARC is involved in adipogenesis, cellular metabolism, extracellular matrix modulation, glucose and lipid metabolism, among others. Furthermore, studies in SPARC knockout mouse model showed that SPARC contributes to adipose tissue formation, non-alcoholic fatty liver disease (NAFLD), and diabetes. Hence, SPARC may represent a novel and interesting target protein for future therapeutic interventions or a biomarker of disease progression. This review summarizes the role of SPARC in the pathophysiology of obesity, and extensively revised SPARC functions in physiological and pathological adipose tissue deposition, muscle metabolism, liver, and diabetes-related pathways.

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.

Evaluation of nonalcoholic fatty liver disease (NAFLD) in severe obesity using noninvasive tests and imaging techniques

The prevalence of nonalcoholic fatty liver disease (NAFLD) and the more severe and inflammatory type, nonalcoholic steatohepatitis (NASH), is increasing rapidly. Especially in high-risk patients, that is those with obesity, metabolic syndrome, and type 2 diabetes mellitus, the prevalence of NAFLD can be as high as 80% while NASH may be present in 20% of these subjects. With the worldwide increase of obesity, it is most likely that these numbers will rise. Since advanced stages of NAFLD and NASH are strongly associated with morbidity and mortality-in particular, cardiovascular disease, liver cirrhosis, and hepatocellular carcinoma-it is of great importance to identify subjects at risk. A great variety of noninvasive tests has been published to diagnose NAFLD and NASH, especially using blood- and imaging-based tests. Liver biopsy remains the gold standard for NAFLD/NASH. This review aims to summarize the different mechanisms leading to NASH and liver fibrosis, the different noninvasive liver tests to diagnose and evaluate patients with severe obesity.

Recent advances and challenges in graphene-based nanocomposite scaffolds for tissue engineering application

Graphene-based nanocomposites have recently attracted increasing attention in tissue engineering because of their extraordinary features. These biocompatible substances, in the presence of an apt microenvironment, can stimulate and sustain the growth and differentiation of stem cells into different lineages. This review discusses the characteristics of graphene and its derivatives, such as their excellent electrical signal transduction, carrier mobility, outstanding mechanical strength with improving surface characteristics, self-lubrication, antiwear properties, enormous specific surface area, and ease of functional group modification. Moreover, safety issues in the application of graphene and its derivatives in terms of biocompatibility, toxicity, and interaction with immune cells are discussed. We also describe the applicability of graphene-based nanocomposites in tissue healing and organ regeneration, particularly in the bone, cartilage, teeth, neurons, heart, skeletal muscle, and skin. The impacts of special textural and structural characteristics of graphene-based nanomaterials on the regeneration of various tissues are highlighted. Finally, the present review gives some hints on future research for the transformation of these exciting materials in clinical studies.

Hura crepitans stem bark extract: A potential remedy to sub-acute liver damage

ETHNOPHARMACOLOGICAL SIGNIFICANCE AND AIM

Hura crepitans is commonly used to treat liver diseases in Nigeria and Ghana. Previous studies have supported its ethnomedicinal use in protecting the liver. The present study aimed at assessing the effect of H. crepitans stem bark on the subacute carbon tetrachloride (CCl₄)-induced liver damage in rats.

MATERIALS AND METHODS

The protective activities of ethanolic extract of H. crepitans stem bark was evaluated in CCl₄-induced subacute liver damage in rats (1:1 v/v in olive oil, intraperitoneally (i.p.), twice weekly for 8 weeks). Blood samples were obtained from the rats and used for some biochemical analysis such as liver function test (Aspartate transaminase, AST; Alanine aminotransferase, ALT; and Alkaline phosphatase, ALP), liver fibrotic indices (Aspartate platelet ratio index, APRI; AST/ALT and AST/PLT ratios) and oxidative stress markers (Malondialdehyde, MDA; Reduced glutathione, GSH; Glutathione S-transferase, GST; Glutathione peroxidase, GPx; and superoxide dismutase, SOD). Histopathological analyses were carried out to determine the expression of pro-inflammatory (NF-κB, COX-2, IL-17 and IL-23) using immunohistochemical techniques.

RESULTS

Oral administration of H. crepitans to CCl₄-induced hepatic injured rats significantly decreased oxidative stress, increased the levels of SOD, GSH, GST and GPx with reduced MDA levels. The plant also mitigated liver injury as evidenced in the significantly reduced levels of AST, ALT and ALP, while it inhibited the inflammatory process via the inhibition of NF-κB, and consequently down-regulateed the pro-inflammatory cytokines COX-2, IL-17 and IL-23, respectively. Biochemical observations were supported by improvement in liver microarchitecture.

CONCLUSION

The Hura crepitans demonstrated antioxidant, antiinflammatory and antifibrotic effect in hepatic injured rats. The study in a way justifies the traditional use of the plant for the treatment of subacute liver diseases in Nigerian Traditional medicine.

Fibrosis and hepatic regeneration mechanism

Liver cirrhosis is the final stage of continuous hepatic inflammatory activity derived by viral, metabolic or autoimmune origin. In the last years, cirrhosis was considered a unique and static condition; recently was accepted some patients subgroups with different liver injury degrees that coexist under the same diagnosis, with implications about the natural disease history. The liver growth factor (LGF) is a potent in vivo and in vitro mitogenic agent and an inducer of hepatic regeneration (HR) through the hepatocytes DNA synthesis. The clinical implications of the LGF levels in cirrhosis, are not clear and even with having a fundamental role in the liver regeneration processes, the studies suggest that it could be a cirrhosis severity marker, in acute liver failure and in chronic hepatitis. Its role as predictor of mortality in fulminant hepatic insufficiency patients has been suggested. HR is one of the most enigmatic and fascinating biological phenomena. The rapid volume and liver function restoration after a major hepatectomy (>70%) or severe hepatocellular damage and its strict regulation of tissue damage response after the cessation, is an exclusive property of the liver. HR is the clinical applications fundament, such as extensive hepatic resections (>70% of the liver parenchyma), segmental transplantation or living donor transplantation, sequential hepatectomies, isolated portal embolization or associated with in situ hepatic transection, temporary artificial support in acute liver failure and the possible cell therapy clinical applications.

The inhibitory effect of PLGA-encapsulated berberine on hepatotoxicity and α-smooth muscle actin (α-SMA) gene expression

BACKGROUND

Liver injury results in excessive extracellular matrix (ECM) deposition in the liver, which is mainly produced by hepatic stellate cells (HSC). Alpha-smooth muscle actin (α-SMA) and liver enzymes are the two hallmarks of liver injury. Previously, it has been confirmed that berberine (BBR) attenuates liver injury. This study aimed to investigate the protective effect of Poly Lactic-co-Glycolic Acid (PLGA) encapsulated BBR against liver injury.

METHODS

Nanoprecipitation, encapsulation, and physio-chemical characterization of BBR-PLGA nanoparticles (BBR-PLGA-NP) have been done. The protective effects of BBR-PLGA-NPs and BBR against carbon tetrachloride (CCl4)-treated Wistar rats were investigated. The serum levels of alanine aminotransferase and aspartate transaminase were measured, and the expression level of α-SMA was quantified by qRT-PCR. To evaluate the liver changes, morphological and histological staining was done.

RESULTS

BBR-PLGA-NPs markedly reduced serum ALT and AST in rats treated with CCl4. Although the expression level of α-SMA was downregulated in the CCl4-injected rats that were treated with BBR, α-SMA expression in this group was still remarkably higher than the control group. α-SMA mRNA was significantly under-expressed (p < 0.05) by BBR-PLGA-NPs and the hepatic histology revealed BBR-PLGA-NPs made further improvements than free BBR.

CONCLUSION

The use of nanoparticle to encapsulate BBR is a worthy approach to enhance the curative effect of BBR against liver injuries, which donate a safe and effective drug delivery strategy to treat liver injuries.

Engineering and Monitoring 3D Cell Constructs with Time-Evolving Viscoelasticity for the Study of Liver Fibrosis In Vitro

Liver fibrosis is generally associated with an over-production and crosslinking of extracellular matrix proteins, causing a progressive increase in both the elastic and viscous properties of the hepatic tissue. We describe a strategy for mimicking and monitoring the mechano-dynamics of the 3D microenvironment associated with liver fibrosis. Cell-laden gelatin hydrogels were crosslinked with microbial transglutaminase using a purpose-designed cytocompatible two-step protocol, which allows for the exposure of cells to a mechanically changing environment during culturing. A bioreactor was re-engineered to monitor the mechanical properties of cell constructs over time. The results showed a shift towards a more elastic (i.e., solid-like) behaviour, which is likely related to an increase in cell stress. The method effectively mimics the time-evolving mechanical microenvironment associated with liver fibrosis and could provide novel insights into pathophysiological processes in which both elastic and viscous properties of tissues change over time.

Glycyrrhizin Attenuates Portal Hypertension and Collateral Shunting via Inhibition of Extrahepatic Angiogenesis in Cirrhotic Rats

Portal hypertension develops along with liver cirrhosis then induces the formation of portal-systemic collaterals and lethal complications. Extrahepatic angiogenesis plays an important role. Glycyrrhizin has been found to exhibit anti-angiogenic features, which leads to its extensive use. However, the relevant effects of glycyrrhizin on liver cirrhosis and portal hypertension have not been evaluated. This study thus aimed to investigate the impact of glycyrrhizin on portal hypertension-related derangements in cirrhotic rats. Male Sprague-Dawley rats received bile duct ligation (BDL) to induce cirrhosis or sham operation as control. The rats were subdivided to receive glycyrrhizin (150 mg/kg/day, oral gavage) or vehicle beginning on the 15th day post operation, when BDL-induced liver fibrosis developed. The effects of glycyrrhizin were determined on the 28th day, the typical timing of BDL-induced cirrhosis. Glycyrrhizin significantly reduced portal pressure (p = 0.004). The splanchnic inflow as measured by superior mesenteric arterial flow decreased by 22% (p = 0.029). The portal-systemic collateral shunting degree reduced by 30% (p = 0.024). The mesenteric angiogenesis and phospho-VEGFR2 protein expression were also downregulated (p = 0.038 and 0.031, respectively). Glycyrrhizin did not significantly influence the liver biochemistry data. Although glycyrrhizin tended to reverse liver fibrosis, statistical significance was not reached (p = 0.069). Consistently, hepatic inflow from portal side, hepatic vascular resistance, and liver fibrosis-related protein expressions were not affected. Glycyrrhizin treatment at the stage of hepatic fibrosis still effectively attenuated portal hypertension and portosystemic collateral shunting. These beneficial effects were attributed to, at least in part, the suppression of mesenteric angiogenesis by VEGF signaling pathway downregulation.

Schisantherin A ameliorates liver fibrosis through TGF-β1mediated activation of TAK1/MAPK and NF-κB pathways in vitro and in vivo

BACKGROUD

Schisandra chinensis, a traditional Chinese medicine for liver protection, can significantly improve liver fibrosis. However, it is still unclear which active components in Schisandra chinensis play an anti-fibrosis role.

PURPOSE

The purpose of present study was to observe the anti-fibrosis effect of schisantherin A (SCA) on liver fibrosis and explore its underlying mechanism.

METHODS

The liver fibrosis model of mice was constructed by the progressive intraperitoneal injection of thioacetamide (TAA), and SCA (1, 2, and 4 mg/kg) was administered by gavage for 5 weeks. The biochemical indicators and inflammatory cytokines were measured, changes in the pathology of the mice liver were observed by hematoxylin & eosin (H&E) and Masson stainings for studying the anti-fibrosis effect of SCA. A hepatic stellate cell (HSCs) activation model induced by transforming growth factor-β1 (TGF-β1) was established, and the effect of SCA on the HSCs proliferation was observed by MTT assay. The expressions of target proteins related to transforming growth factor-β-activated kinase 1 (TAK1)/mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) pathways were evaluated by western blotting, immunohistochemistry or immunofluorescence analysis, to explore the potential mechanism of SCA.

RESULTS

SCA could significantly ameliorate the pathological changes of liver tissue induced by TAA, and reduce the serum transaminase level, the hydroxyproline level and the expression of α-smooth muscle actin (α-SMA) and collagen 1A1 (COL1A1) proteins in the liver tissue. SCA could significantly lower the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) in the serum and liver tissue, and down-regulate the expression of target proteins related to TAK1/MAPK and NF-κB pathways in the liver tissue. The in vitro studies demonstrated that SCA significantly inhibited the proliferation and activation of HCS-T6 cells induced by TGF-β1, decreased TNF-α and IL-6 levels, and inhibited the TAK1 activation induced by TGF-β1 and then the expression of MAPK and NF-κB signaling pathway-related proteins.

CONCLUSION

Together, SCA can ameliorate the liver fibrosis induced by TAA and the HSC-T6 cell activation induced by TGF-β1 in mice, and its mechanism may be to inhibit the HSCs activation and inflammatory response by inhibiting TGF-β1 mediated TAK1/MAPK and signal pathways.

The Role of Viruses in Carcinogenesis and Molecular Targeting: From Infection to Being a Component of the Tumor Microenvironment

About a tenth of all cancers are caused by viruses or associated with viral infection. Recent global events including the coronavirus disease-2019 (COVID-19) pandemic means that human encounter with viruses is increased. Cancer development in individuals with viral infection can take many years after infection, demonstrating that the involvement of viruses in cancer development is a long and complex process. This complexity emanates from individual genetic heterogeneity and the many steps involved in cancer development owing to viruses. The process of tumorigenesis is driven by the complex interaction between several viral factors and host factors leading to the creation of a tumor microenvironment (TME) that is ideal and promotes tumor formation. Viruses associated with human cancers ensure their survival and proliferation through activation of several cellular processes including inflammation, migration, and invasion, resistance to apoptosis and growth suppressors. In addition, most human oncoviruses evade immune detection and can activate signaling cascades including the PI3K-Akt-mTOR, Notch and Wnt pathways associated with enhanced proliferation and angiogenesis. This expert review examines and synthesizes the multiple biological factors related to oncoviruses, and the signaling cascades activated by these viruses contributing to viral oncogenesis. In particular, I examine and review the Epstein-Barr virus, human papillomaviruses, and Kaposi's sarcoma herpes virus in a context of cancer pathogenesis. I conclude with a future outlook on therapeutic targeting of the viruses and their associated oncogenic pathways within the TME. These anticancer strategies can be in the form of, but not limited to, antibodies and inhibitors.

Fibrotic Events in the Progression of Cholestatic Liver Disease

Cholestatic liver diseases including primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are associated with active hepatic fibrogenesis, which can ultimately lead to the development of cirrhosis. However, the exact relationship between the development of liver fibrosis and the progression of cholestatic liver disease remains elusive. Periductular fibroblasts located around the bile ducts seem biologically different from hepatic stellate cells (HSCs). The fibrotic events in these clinical conditions appear to be related to complex crosstalk between immune/inflammatory mechanisms, cytokine signalling, and perturbed homeostasis between cholangiocytes and mesenchymal cells. Several animal models including bile duct ligation (BDL) and the Mdr2-knockout mice have improved our understanding of mechanisms underlying chronic cholestasis. In the present review, we aim to elucidate the mechanisms of fibrosis in order to help to identify potential diagnostic and therapeutic targets.

Congestion Area of the Right Lobe Graft in Living Donor Liver Transplantation: Quantitative Evaluation of Hemodynamics Using Computed Tomography Perfusion

BACKGROUND

The hemodynamics of congestion areas in the right lobe graft after living donor liver transplantation (LDLT) remains unclear. The aim of this study was to elucidate the hemodynamics of congestion areas in the right lobe graft after LDLT using computed tomography (CT) perfusion imaging and the dual-input maximum slope method.

METHODS

Sixteen recipients underwent CT perfusion of the liver and portal phase abdominal to pelvic CT 1week after LDLT using a right lobe graft. The attenuation of segments V and VIII on the portal venous phase abdominal to the pelvic CT scan was classified into 3 categories: hyperattenuation, iso-attenuation, and hypoattenuation. Mean arterial blood flow (AF, mL/min/100 mL tissue), portal blood flow (PF, mL/min/100 mL tissue), and perfusion index (%) [PI = AF/(AF + PF) × 100] were compared between the hyperattenuation group and iso-attenuation group. The independent t test was used for these statistical analyses.

RESULTS

On the portal phase abdominal scan, 15 segments, 16 segments, and 1 segment showed hyperattenuation, iso-attenuation, and hypoattenuation, respectively. The mean AF and PI of the hyperattenuation group (44.4 ± 24.4, 30.2 ± 13.5) were significantly higher than those of the iso-attenuation group (28.0 ± 7.8, 19.9 ± 6.2) (P < .05, P < .05).

CONCLUSIONS

The congested liver segments showed high AF and high PI on CT perfusion imaging. This method enables the feasible quantification of the hemodynamics and the description of focal hemodynamic change in the graft after LDLT.

Metabolic Dysfunction-Associated Fatty Liver Disease (MAFLD)-A Condition Associated with Heightened Sympathetic Activation

Metabolic dysfunction-associated fatty liver disease (MAFLD) is the most common liver disease affecting a quarter of the global population and is often associated with adverse health outcomes. The increasing prevalence of MAFLD occurs in parallel to that of metabolic syndrome (MetS), which in fact plays a major role in driving the perturbations of cardiometabolic homeostasis. However, the mechanisms underpinning the pathogenesis of MAFLD are incompletely understood. Compelling evidence from animal and human studies suggest that heightened activation of the sympathetic nervous system is a key contributor to the development of MAFLD. Indeed, common treatment strategies for metabolic diseases such as diet and exercise to induce weight loss have been shown to exert their beneficial effects at least in part through the associated sympathetic inhibition. Furthermore, pharmacological and device-based approaches to reduce sympathetic activation have been demonstrated to improve the metabolic alterations frequently present in patients with obesity, MetSand diabetes. Currently available evidence, while still limited, suggests that sympathetic activation is of specific relevance in the pathogenesis of MAFLD and consequentially may offer an attractive therapeutic target to attenuate the adverse outcomes associated with MAFLD.

α-mangostin preserves hepatic microvascular architecture in fibrotic rats as shown by scanning electron microscopy of vascular corrosion casts

Liver fibrosis is a dynamic condition caused by wound-healing in which scar tissue replaces the liver parenchyma following repetitive injuries. It is hypothesized that α-mangostin (AM), the major constituent of the xanthone fraction in extracts of Garcinia mangostana L., may protect the hepatic microvascular bed from thioacetamide (TAA)-induced fibrosis. In the present study, rats were divided into 4 groups: Control rats received no treatment; TAA-treated rats received 150 mg/kg TAA 3 times per week intraperitoneally; AM-treated rats received 75 mg/kg AM twice per week intraperitoneally; and TAA+AM-treated rats received both TAA and AM as described above. Rat livers were processed either for light microscopy or for vascular corrosion casting after 30 and 60 days of treatment. Vascular parameters were measured by 3D morphometry analysis of scanning electron micrographs. AM attenuated hepatocellular injuries and delayed both periportal and pericentral fibrosis in the TAA-treated rats. The comparison of findings at day 30 and 60 showed that TAA-induced fibrotic changes were progressive in time, and that the beneficial effects of AM only became apparent after prolonged treatment. The livers of rats treated with both TAA and AM had less space surrounding the portal vessels, improved preservation of the hepatic microvascular pattern, and minimally altered sinusoidal patterns with few signs of terminal portal venule remodeling. AM therefore partially protected the liver against hepatotoxin-induced fibrosis and the associated microvascular changes. The mechanism of the protective effect of AM on the liver remains to be investigated.

MRI Measures of Murine Liver Fibrosis

BACKGROUND

An imaging method that allows quantitative fibrosis estimates is needed to facilitate the diagnosis of chronic liver disease. Amide proton transfer (APT) and tissue sodium concentration (TSC) estimates could meet this need.

HYPOTHESIS

APT and TSC estimates correlate with fibrosis in a mouse model of chronic liver disease.

STUDY TYPE

Prospective.

PHANTOMS/ANIMAL MODEL

Male C57Bl/6 mice given CCl₄ or vehicle (N = 8 each) twice weekly for 16 weeks.

FIELD STRENGTH/SEQUENCE

Liver T₁ (Look-Locker gradient recalled echo [GRE] sequence), T₂ (multiecho spin echo sequence), T_1rho (fast spin echo sequence with 500 Hz spin locking pulse), and APT (GRE sequence with off-resonance pulses) data were acquired at 7 T at 12 and 16 weeks. Liver sodium data (multiple echo GRE sequence) were acquired at 12 weeks at 9.4 T.

ASSESSMENT

Liver proton T₁ , T₂ , T_1rho , APT, sodium T₂ *, and TSC were calculated. Histological measures included Sirius Red, hematoxylin and eosin, liver hydroxyproline content, and serum alanine transaminase (ALT).

STATISTICAL TESTS

Welch's two-sided t-test was used to test for differences between control and CCl₄ -treated groups for serum ALT, hydroxyproline, Sirius Red staining, T₁ , T₂ , T_1rho , APT, TSC, and sodium T₂ *. Pearson's correlations between liver T₁ , APT, TSC, or sodium T₂ * with Sirius Red staining and hydroxyproline levels were calculated.

RESULTS

APT was significantly different (P < 0.05) between groups in the left liver lobe at 16 weeks (CCl₄ : 8.0% ± 1.2%, controls: 6.2% ± 1.0%), as were average liver TSC at 12 weeks (CCl₄ : 38 mM ± 5 mM, controls: 27 mM ± 2 mM), and average sodium liver T₂ * at 12 weeks (CCl₄ : 10 msec ± 1.0 msec, controls: 12 msec ± 1.9 msec). APT, TSC, and sodium T₂ * correlated significantly (P < 0.05) with Sirius Red staining and hydroxyproline levels.

DATA CONCLUSION

Liver TSC and APT significantly correlated with histopathologic markers of fibrosis in this mouse model.

EVIDENCE LEVEL

1 TECHNICAL EFFICACY: Stage 3.

Hepatitis C Virus Cure in Human Immunodeficiency Virus Coinfection Dampens Inflammation and Improves Cognition Through Multiple Mechanisms

BACKGROUND

Chronic inflammation in human immunodeficiency virus (HIV)/hepatitis C virus (HCV) coinfection increases cognitive impairment. With newer, direct-acting antiviral therapies for HCV, our objective was to determine whether chronic inflammation would be decreased and cognition improved with HCV sustained viral response (SVR) in coinfection.

METHODS

We studied 4 groups longitudinally: 7 HCV-monoinfected and 12 HIV/HCV-coinfected persons before and after treatment for HCV, 12 HIV-monoinfected persons, and 9 healthy controls. We measured monocyte activation and gene expression, monocyte-derived exosome micro-ribonucleic acid (miRNA) expression, plasma inflammation, and cognitive impairment before and after therapy.

RESULTS

Plasma soluble CD163 and neopterin were decreased in HCV mono- and coinfected persons. Blood CD16+ monocytes were decreased in coinfection after HCV treatment. Global deficit score improved 25% in coinfection with the visual learning/memory domain the most improved. Hepatitis C virus SVR decreased monocyte interferon genes MX1, IFI27, and CD169 in coinfection and MX1, LGALS3BP, and TNFAIP6 in HCV monoinfection. Monocyte exosomes from coinfected persons increased in microRNA (miR)-19a, miR-221, and miR-223, all of which were associated with decreasing inflammation and nuclear factor-κB activation.

CONCLUSIONS

Hepatitis C virus cure in coinfection brings monocyte activation to levels of HIV alone. Cognitive impairment is significantly improved with cure but not better than HIV infection alone, which strong suggests that cognitive impairment was driven by both HIV and HCV.SummaryHCV cure in HIV coinfection improves monocyte and plasma activation markers and increases cognitive function in the visual learning/memory domain.

Non-alcoholic fatty liver disease: An overview of risk factors, pathophysiological mechanisms, diagnostic procedures, and therapeutic interventions

Non-alcoholic fatty liver disease (NAFLD) is a disorder of excessive fat accumulation in the liver, known as steatosis, without alcohol overconsumption. NAFLD can either manifest as simple steatosis or steatohepatitis, known as non-alcoholic steatohepatitis (NASH), which is accompanied by inflammation and possibly fibrosis. Furthermore, NASH might progress to hepatocellular carcinoma. NAFLD and NASH prevalence is in a continuous state of growth, and by 2018, NAFLD became a devastating metabolic disease with a global pandemic prevalence. The pathophysiology of NAFLD and NASH is not fully elucidated, but is known to involve the complex interplay between different metabolic, environmental, and genetic factors. In addition, unhealthy dietary habits and pre-existing metabolic disturbances together with other risk factors predispose NAFLD development and progression from simple steatosis to steatohepatitis, and eventually to fibrosis. Despite their growing worldwide prevalence, to date, there is no FDA-approved treatment for NAFLD and NASH. Several off-label medications are used to target disease risk factors such as obesity and insulin resistance, and some medications are used for their hepatoprotective effects. Unfortunately, currently used medications are not sufficiently effective, and research is ongoing to investigate the beneficial effects of different drugs and phytochemicals in NASH. In this review article, we outline the different risk factors and pathophysiological mechanisms involved in NAFLD, diagnostic procedures, and currently used management techniques.

MiR-15b and miR-16 suppress TGF-β1-induced proliferation and fibrogenesis by regulating LOXL1 in hepatic stellate cells

Activation of hepatic stellate cells (HSCs) is an important event during the progress of liver fibrosis. MicroRNA (miR)-15b and miR-16 have been found to be involved in activation of HSCs. However, the roles of miR-15b/16 in liver fibrosis remain unclear. The expression of miR-15b/16 was decreased in TGF-β1-stimulated LX-2 cells. Overexpression of miR-15b/16 in LX-2 cells suppressed TGF-β1-induced cell proliferation and the expression levels of tissue inhibitor of metalloproteinase type 1, collagen type I, and α-smooth muscle actin. The activation of Smad2/3 caused by TGF-β1 was repressed by miR-15b/16 overexpression. The two miRNAs directly bound to the 3'-UTR of lysyl oxidase-like 1 (LOXL1) and suppressed the LOXL1 expression. Furthermore, knockdown of LOXL1 attenuated miR-15b/16 downregulation-induced cell proliferation, fibrogenic response and phosphorylation of Smad2/3. Collectively, miR-15b/16 exhibited anti-fibrotic activity through regulation of Smad2/3 pathway.

Noninvasive assessment of liver fibrosis by dual-layer spectral detector CT

PURPOSE

To elucidate the diagnostic ability of liver fibrosis using (1) liver parenchymal iodine density on equilibrium computed tomographic imaging and (2) extracellular volume (ECV) measured by dual-layer spectral detector CT.

METHODS

From April 2018 to June 2019, 68 patients [mean age, 62 years; 39 males, 29 females] underwent dynamic contrast-enhanced CT by a dual-layer spectral detector CT system before liver transplantation or liver resection. The iodine densities of liver parenchyma (I _liver) and aorta (I _aorta) were independently measured by two radiologists at the equilibrium phase. The iodine-density ratio (I-ratio) (I _liver/ I _aorta) and the CT-ECV were calculated. Spearman's rank correlation coefficient was used to analyze the relationship between the I-ratio or the CT-ECV and the fibrosis stage. A receiver operating characteristic (ROC) curve analysis was performed to determine the accuracy of the I-ratio and the CT-ECV for discriminating fibrosis stages.

RESULTS

For both readers, the I-ratio and the CT-ECV increased significantly as the fibrosis stage advanced (I-ratio: rho = 0.380 and 0.443, p < 0.01; CT-ECV: rho = 0.423 and 0.469, p < 0.01). The CT-ECV showed better diagnostic accuracy for staging fibrosis, and the area under the ROC curve values for discriminating F4 stage were 0.884 and 0.925. The two readers' cutoff values of the CT-ECV for diagnosing fibrosis as F4 were 26.2 % and 29.3 %, with 95.0 % and 90.0 % sensitivity and 72.9 % and 85.4 % specificity, respectively.

CONCLUSION

The liver parenchymal iodine density on the equilibrium phase and the CT-ECV can be useful for predicting a high stage of liver fibrosis.

A Review of Liver Fibrosis and Emerging Therapies

With the increasing burden of liver cirrhosis, the most advanced stage of hepatic fibrosis, there is a need to better understand the pathological processes and mechanisms to target specific treatments to reverse or cease fibrosis progression. Antiviral therapy for hepatitis B and C has effectively treated underlying causes of chronic liver disease and has induced fibrosis reversal in some; however, this has not been targeted for the majority of aetiologies for cirrhosis including alcohol or nonalcoholic steatohepatitis. Fibrosis, characterised by the accumulation of extracellular matrix proteins, is caused by chronic injury from toxic, infectious, or metabolic causes. The primary event of fibrogenesis is increased matrix production and scar formation mediated by the hepatic stellate cell, which is the principal cell type involved. Experimental models using rodent and human cell lines of liver injury have assisted in better understanding of fibrogenesis, especially in recognising the role of procoagulant factors. This has led to interventional studies using anticoagulants in animal models with reversal of fibrosis as the primary endpoint. Though these trials have been encouraging, no antifibrotic therapies are currently licenced for human use. This literature review discusses current knowledge in the pathophysiology of hepatic fibrosis, including characteristics of the extracellular matrix, signalling pathways, and hepatic stellate cells. Current types of experimental models used to induce fibrosis, as well as up-to-date anticoagulant therapies and agents targeting the hepatic stellate cell that have been trialled in animal and human studies with antifibrotic properties, are also reviewed.

CD14+ monocytes and CD163+ macrophages correlate with the severity of liver fibrosis in patients with chronic hepatitis C

Hepatic fibrosis is a crucial pathological process involved in the development of chronic hepatitis C (CHC) and may progress to liver cirrhosis and hepatocellular carcinoma. Activated peripheral blood monocytes and intrahepatic macrophages further promote hepatic fibrogenesis by releasing proinflammatory and profibrogenic cytokines. The present study aimed to investigate the role of peripheral CD14⁺ monocytes and intrahepatic CD163⁺ macrophages in hepatitis C virus (HCV)-associated liver fibrosis and clarify whether serum soluble CD163 (sCD163) may serve as a fibrosis marker in patients with CHC. A total of 87 patients with CHC and 20 healthy controls were recruited. Serum sCD163 levels were measured by ELISA. Frequencies of peripheral CD14⁺ monocytes and inflammatory cytokines expressed by CD14⁺ monocytes were analyzed by flow cytometry. The degree of fibrosis in human liver biopsies was graded using the Metavir scoring system and patients were stratified into two groups based on those results (F<2 vs. F≥2). Hepatic expression of CD163 was examined by immunohistochemical staining. The diagnostic values of sCD163, aspartate aminotransferase to platelet ratio index (APRI), fibrosis 4 score (FIB-4) and the aspartate aminotransferase to alanine aminotransferase ratio (AAR) in significant fibrosis (F≥2) were evaluated and compared using receiver operating characteristic (ROC) curves. The results indicated that the serum sCD163 levels and the frequency of CD14⁺ monocytes were significantly higher in the patients than that in the controls and positively correlated with liver fibrosis. The level of serum sCD163 was consistent with hepatic CD163 expression in the liver sections from patients. The frequencies of interleukin (IL)-8- and tumor necrosis factor-α-expressing monocytes were increased and that of IL-10-expressing monocytes was decreased in the patients. The area under the ROC curve (AUROC) for sCD163, APRI, FIB-4 and AAR was 0.876, 0.785, 0.825 and 0.488, respectively, and the AUROC for sCD163 was significantly higher than those for APRI and AAR. In conclusion, sCD163 may serve as a novel marker for assessing the degree of liver fibrosis in HCV-infected patients.

Renal injury and hepatic effects from the methylimidazolium ionic liquid M8OI in mouse

The ionic liquid 1-octyl-3-methylimidazolium (M8OI) has been found in the environment and identified as a hazard for triggering the liver disease primary biliary cholangitis (PBC). Given limited toxicity data for M8OI and other structurally-related ionic liquids, target organs for M8OI toxicity were examined. Adult male C57Bl6 mice were acutely exposed to 0-10 mg/kg body weight M8OI via 2 intraperitoneal injections (time zero and 18 h) and effects examined at 24 h. At termination, tissue histopathology, serum and urinary endpoints were examined. No overt pathological changes were observed in the heart and brain. In contrast, focal and mild to multifocal and moderate degeneration with a general trend for an increase in severity with increased dose was observed in the kidney. These changes were accompanied by a dose-dependent increased expression of Kim1 in kidney tissue, marked elevations in urinary Kim1 protein and a dose-dependent increase in serum creatinine. Hepatic changes were limited to a significant dose-dependent loss of hepatic glycogen and a mild but significant increase in portal tract inflammatory recruitment and/or fibroblastic proliferation accompanied by a focal fibrotic change. Cultured mouse tissue slices reflected these in vivo effects in that dose-dependent injury was observed in kidney slices but not in the liver. Kidney slices accumulated higher levels of M8OI than liver slices (e.g. at 10 μM, greater than 4 fold) and liver slices where markedly more active in the metabolism of M8OI. These data indicate that the kidney is a target organ for the toxic effects of M8OI accompanied by mild cholangiopathic changes in the liver after intraperitoneal administration.

Differentiating mild and substantial hepatic fibrosis from healthy controls: a comparison of diffusion kurtosis imaging and conventional diffusion-weighted imaging

BACKGROUND

Early and accurate detection of liver fibrosis are important for clinical treatment.

PURPOSE

To compare the diagnostic accuracy of liver diffusion kurtosis imaging (DKI) and conventional diffusion-weighted imaging (cDWI) in differentiating patients with mild and substantial fibrosis from normal individuals.

MATERIAL AND METHODS

Twenty-seven healthy volunteers with no fibrosis (S0) and 45 patients with mild (S1) or substantial (S2) liver fibrosis underwent DWI with multiple b-values. Liver mean apparent diffusion (MD) and mean kurtosis (MK) values derived from DKI and apparent diffusion coefficient (ADC) derived from cDWI were measured and compared. Their discriminative abilities were analyzed and compared by receiver operating characteristic (ROC) curve analysis.

RESULTS

Significant differences in MD and ADC values were found between groups (P < 0.05). MD value was statistically different between S0 and S1 (P = 0.028) and S0 and S2 (P = 0.005). ADC value was statistically different between S0 and S2 (P = 0.012). MK value was similar between groups (P = 0.646). MD and ADC values significantly correlated with fibrosis stages (r_s = -0.668, -0.341; P < 0.01). MK values had no correlation with fibrosis stages (r_s = 0.180; P = 0.130). The area under ROC curves (AUC) for MD and ADC was 0.937 and 0.707 for characterization of S1-2 and 0.817 and 0.658 for S2, respectively. MD performed better than ADC for characterization of S1-2 and S2 (P < 0.05).

CONCLUSION

Differentiating patients with mild or substantial fibrosis from normal individuals is feasible using DKI, which performs better than cDWI.

A case of focal confluent hepatic fibrosis in the patient with hepatitis C virus-related liver cirrhosis: a mimic of cholangiolocellular carcinoma

During routine ultrasound examination, a hyperechoic mass was detected in the anterior segment of the liver in an 80-year-old woman with hepatitis C virus-related cirrhosis. Computed tomography and magnetic resonance imaging findings suggested a malignant tumor with abundant fibrous stroma, similar to cholangiolocellular carcinoma. However, subsequent partial hepatectomy revealed a mass characterized by abundant fibrosis without tumor cells, dilated blood vessels, and marginal ductular reaction. Accordingly, focal confluent fibrosis was diagnosed. Generally, the diagnosis of focal confluent fibrosis is straightforward because of its well-established imaging characteristics. However, its differentiation from a malignant tumor can occasionally be difficult because of variation in presentation depending on the amount of fibrous stroma and the degree of inflammatory cell infiltration. In the present case, diagnosis was difficult because the lesion was more localized than usual, presenting a mass-like shape, and there was obvious hyperintensity on T2-weighted imaging and ring-shaped hyperintensity on diffusion-weighted imaging. Moreover, hepatic capsular retraction was indistinct, which can be one of the key findings of focal confluent fibrosis. When a hepatic mass is associated with a fibrous lesion, focal confluent fibrosis should be considered in the differential diagnosis, even though the lesion is associated with several atypical findings.

The effects of inhibiting the activation of hepatic stellate cells by lignan components from the fruits of Schisandra chinensis and the mechanism of schisanhenol

Liver fibrosis is a pathological manifestation induced by chronic liver injury and may cause cirrhosis and liver cancer with the chronic progression of fibrosis. During the onset and progression of liver fibrosis, the activation of hepatic stellate cells (HSCs) is the core mechanism for the secretion of many extracellular matrices to induce fibrosis. Lignans are reportedly the main effective components of Schisandra chinensis with good anti-fibrosis effects. In this study, we compared the inhibiting effects of the seven lignan components from S. chinensis on HSC activation. We found that the seven lignans inhibited the activation of human HSCs (LX-2) in various degrees. Among all lignans, schisanhenol showed the best effect in inhibiting the activation of LX-2 with a dose-effect relationship. Sal also inhibited the phosphorylations of Smad1, Smad2, Smad3, extracellular regulated protein kinase (ERK), c-Jun N-terminal kinase (JNK), p38, and nuclear transcription factor-κB (NF-κB), as well as downregulated Smad4. All these findings suggested that schisanhenol may ameliorate liver fibrosis by inhibiting the transforming growth factor β (TGF-β)/Smad and mitogen-activated protein kinase (MAPK) signaling pathways. Remarkably, schisanhenol may be a potential anti-liver fibrosis drug and warrants further research.

Up-regulation of microRNA-30b/30d cluster represses hepatocyte apoptosis in mice with fulminant hepatic failure by inhibiting CEACAM1

Recently, impacts of microRNAs have been unraveled in human diseases, and we aimed to confirm the role of miR-30b/30d in fulminant hepatic failure (FHF). Expression of miR-30b/30d and CEACAM1 in serum of FHF patients and healthy people was measured by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis. Mice FHF models were established by injection of D-Galn and lipopolysaccharide, and were treated with miR-30b/30d mimics. Oxidative stress, liver injury, and inflammatory reaction in mouse liver tissues were measured using oxidative stress-related factor kits, hematoxylin-eosin staining and enzyme-linked immunosorbent assay, respectively. Moreover, cell cycle distribution and apoptosis of hepatocytes of mice were determined by flow cytometry, and the target relation between miR-30b/30d and CEACAM1 was confirmed by bioinformatic method and dual luciferase reporter gene assay. MiR-30b/30d expression was positively, and CEACAM1 expression was negatively related to prognosis of FHF patients. Up-regulation of miR-30b/30d attenuated oxidative stress, liver injury, and inflammatory reaction, and improved survival rate of FHF mice. Furthermore, elevated miR-30b/30d ameliorated apoptosis and cell cycle arrest of hepatocytes of FHF mice. CEACAM1 was a target gene of miR-30b/30d. This study highlights that up-regulated miR-30b/30d attenuates the progression of FHF by targeting CEACAM1, which may be helpful to FHF treatment.

The toxicity of the methylimidazolium ionic liquids, with a focus on M8OI and hepatic effects

Ionic liquids are a diverse range of charged chemicals with low volatility and often liquids at ambient temperatures. This characteristic has in part lead to them being considered environmentally-friendly replacements for existing volatile solvents. However, methylimidazolium ionic liquids are slow to break down in the environment and a recent study at Newcastle detected 1 octyl 3 methylimidazolium (M8OI) - an 8 carbon variant methylimidazolium ionic liquid - in soils in close proximity to a landfill site. The current M8OI toxicity database in cultured mammalian cells, in experimental animal studies and in model indicators of environmental impact are reviewed. Selected analytical data from the Newcastle study suggest the soils in close proximity to the landfill site, an urban soil lacking overt contamination, had variable levels of M8OI. The potential for M8OI - or a structurally related ionic liquid - to trigger primary biliary cholangitis (PBC), an autoimmune liver disease thought to be triggered by an unknown agent(s) in the environment, is reviewed.

Sex Differences, Cocaine Use, and Liver Fibrosis Among African Americans in the Miami Adult Studies on HIV Cohort

Background: HIV infection disproportionally affects African Americans. Liver disease is a major cause of non-HIV morbidity and mortality in this population. Substance abuse accelerates HIV disease and may facilitate progression of liver disease. This study investigated the relationship between sex differences and cocaine use with liver injury, characterized as hepatic fibrosis. Materials and Methods: A cross-sectional study was conducted on 544 African Americans [369 people living with HIV (PLWH) and 175 HIV seronegative] from the Miami Adult Studies on HIV (MASH) cohort. Cocaine use was determined with a validated self-reported questionnaire and confirmed with urine screen. Fasting blood was used to estimate liver fibrosis using the noninvasive fibrosis-4 (FIB-4) index. Results: Men living with HIV had 1.79 times higher odds for liver fibrosis than women living with HIV (p = 0.038). African American women had higher CD4 count (p = 0.001) and lower HIV viral load (p = 0.011) compared to African American men. Fewer women (PLWH and HIV seronegative) smoked cigarettes (p = 0.002), and fewer had hazardous or harmful alcohol use (p < 0.001) than men. Women also had higher body mass index (kg/m²) (p < 0.001) compared to men. No significant association was noted among HIV seronegative participants for liver fibrosis by sex differences or cocaine use. Among African Americans living with HIV, cocaine users were 1.68 times more likely to have liver fibrosis than cocaine nonusers (p = 0.044). Conclusions: Sex differences and cocaine use appear to affect liver disease among African Americans living with HIV pointing to the importance of identifying at-risk individuals to improve outcomes of liver disease.

Liver injury monitoring, fibrosis staging and inflammation grading using T1rho magnetic resonance imaging: an experimental study in rats with carbon tetrachloride intoxication

Background

To investigate the merit of T1rho relaxation for the evaluation of liver fibrosis, inflammatory activity, and liver injury monitoring in a carbon tetrachloride (CCl₄)-induced rat model.

Methods

Model rats from CCl₄-induced liver fibrosis (fibrosis group: n = 41; regression group: n = 20) and control (n = 11) groups underwent black blood T1rho magnetic resonance (MR) imaging (MRI). Injection of CCl₄ was done twice weekly for up to 12 weeks in the fibrosis group and for up to 6 weeks in the regression group. MR scanning time points were at baseline and at 2, 4, 6, 8, 10 and 12 weeks after CCl₄ injection in the fibrosis group and at baseline and at 2, 4, 6 (CCl₄ withdrawal), 7, 8, 10 and 12 weeks in the regression group.

Results

In the fibrosis group, liver T1rho values increased gradually within week 8 and then decreased. In the regression group, T1rho values dropped gradually after the withdrawal of CCl₄ and fell below those at baseline. The T1rho values at S0 were lower than those at any other stage (all P < 0.05). The T1rho values at G0 were significantly lower than those at any other grade, and G1 was lower than G2 (all P < 0.01). The T1rho values mildly correlated with fibrosis stages (r = 0.362) and moderately correlated with grades of inflammation (r = 0.568). The T1rho values of rats with the same inflammation grades showed no significant difference among different fibrosis stages, and the T1rho values at S3 showed a significant difference among different grades of inflammation (P = 0.024). Inflammation grade was an independent variable associated with T1rho values (P < 0.001).

Conclusion

T1rho MRI can be used to monitor CCl₄-induced liver injury, and inflammatory activity had a greater impact on liver T1rho values than fibrosis.

FABP4 and MMP9 levels identified as predictive factors for poor prognosis in patients with nonalcoholic fatty liver using data mining approaches and gene expression analysis

Nonalcoholic fatty liver (NAFLD) may progress to nonalcoholic steatohepatitis (NASH) and ultimately to cirrhosis and hepatocellular carcinoma (HCC). Prognostic markers for these conditions are poorly defined. The aim of this study was to identify predictive gene markers for the transition from NAFL to NASH and then to poorer conditions. Gene expression omnibus datasets associated with a prediction analysis algorithm were used to create a matrix composed of control subject (n = 52), healthy obese (n = 51), obese with NAFL (n = 42) and NASH patients (n = 37) and 19,085 genes in order to identify specific genes predictive of the transition from steatosis to NASH and from NASH to cirrhosis and HCC and thus patients at high risk of complications. A validation cohort was used to validate these results. We identified two genes, fatty acid binding protein-4 (FABP4) and matrix metalloproteinase-9 (MMP9), which respectively allowed distinguishing patients at risk of progression from NAFL to NASH and from NASH to cirrhosis and HCC. Thus, NAFL patients expressing high hepatic levels of FABP4 and NASH patients expressing high hepatic levels of MMP9 are likely to experience disease progression. Therefore, using FABP4 and MMP9 as blood markers could help to predict poor outcomes and/or progression of NAFL during clinical trial follow-up.

The Upstream Pathway of mTOR-Mediated Autophagy in Liver Diseases

Autophagy, originally found in liver experiments, is a cellular process that degrades damaged organelle or protein aggregation. This process frees cells from various stress states is a cell survival mechanism under stress stimulation. It is now known that dysregulation of autophagy can cause many liver diseases. Therefore, how to properly regulate autophagy is the key to the treatment of liver injury. mechanistic target of rapamycin (mTOR)is the core hub regulating autophagy, which is subject to different upstream signaling pathways to regulate autophagy. This review summarizes three upstream pathways of mTOR: the phosphoinositide 3-kinase (PI3K)/protein kinase (AKT) signaling pathway, the adenosine monophosphate-activated protein kinase (AMPK) signaling pathway, and the rat sarcoma (Ras)/rapidly accelerated fibrosarcoma (Raf)/mitogen-extracellular activated protein kinase kinase (MEK)/ extracellular-signal-regulated kinase (ERK) signaling pathway, specifically explored their role in liver fibrosis, hepatitis B, non-alcoholic fatty liver, liver cancer, hepatic ischemia reperfusion and other liver diseases through the regulation of mTOR-mediated autophagy. Moreover, we also analyzed the crosstalk between these three pathways, aiming to find new targets for the treatment of human liver disease based on autophagy.

Inhibition of Heme Oxygenase Antioxidant Activity Exacerbates Hepatic Steatosis and Fibrosis In Vitro

The progression of non-alcoholic fatty liver disease (NAFLD) and the development of hepatic fibrosis is caused by changes in redox balance, leading to an increase of reactive oxygen species (ROS) levels. NAFLD patients are at risk of progressing to non-alcoholic steatohepatitis (NASH), associated to cardiovascular diseases (CVD), coronary heart disease and stroke. Heme Oxygenase-1 (HO-1) is a potent endogenous antioxidant gene that plays a key role in decreasing oxidative stress. The present work was directed to determine whether use of an inhibitor of HO-1 activity affects lipid metabolism and fibrosis process in hepatic cells. Oil Red assay and mRNA analysis were used to evaluate the triglycerides content and the lipid metabolism pathway in HepG2 cells. ROS measurement, RT-PCR and Soluble collagen assay were used to assess the intracellular oxidant, the fibrosis pathway and the soluble collagen in LX2 cells. The activity of HO-1 was inhibited using Tin Mesoporphyrin IX (SnMP). Our study demonstrates that a non-functional HO system results in an increased lipid storage and collagen release in hepatocytes. Consequently, an increase of HO-1 levels may provide a therapeutic approach to address the metabolic alterations associated with NAFLD and its progression to NASH.

Human Liver-Derived Stem Cells Improve Fibrosis and Inflammation Associated with Nonalcoholic Steatohepatitis

Cell therapy may be regarded as a feasible alternative to whole organ transplantation to treat end-stage liver diseases. Human liver stem cells (HLSCs) are a population of cells easily obtainable and expandable from a human adult liver biopsy. HLSCs share with mesenchymal stromal cells the same phenotype, gene expression profile, and differentiation capabilities. In addition, HLSCs show a specific commitment to the hepatic phenotype. Injection of HLSCs into immunodeficient mice fed with a methionine-choline-deficient diet to induce nonalcoholic steatohepatitis ameliorates liver function and morphology. In particular, HLSC treatment induced a reduction of liver fibrosis and inflammation at morphological and molecular levels. Moreover, HLSCs were able to persist for up to 3 weeks after the injection. In conclusion, HLSCs have healing effects in a model of chronic liver disease.

Alogliptin alleviates liver fibrosis via suppression of activated hepatic stellate cell

Liver fibrosis occurs in most types of chronic liver diseases. The understanding of the pathogenesis of liver fibrosis has grown considerably, but the effective treatments are still lacking. Alogliptin, a classical Dipeptidyl peptidase-4 (DPP4) inhibitor with great effects on type 2 diabetes, has shown the potential to protect liver, but its effects on the progression of liver fibrosis have not been clarified. Herein, we explored the anti-fibrosis effects of alogliptin. In vitro, we demonstrated that alogliptin suppressed the activation of LX-2 upon transforming growth factor-β (TGF-β) challenge. In vivo, chronic treatment with alogliptin alleviated hepatic steatosis and protected from the liver injury in ob/ob mice, which delayed the progression of liver fibrosis. Furthermore, alogliptin significantly relieved the hepatic fibrosis in CCl4-induced liver fibrosis mouse model. In conclusion, our results demonstrate that negatively modulation of alogliptin on hepatic stellate cell (HSC) activation might contribute to liver fibrosis alleviation. Our research provides the potential possibility of alogliptin on the application for liver fibrosis therapy and suggests that DPP4 may be a novel target for liver fibrosis therapy.

Lanostane-type triterpenoids from the fruiting bodies of Ganoderma applanatum

Twelve previously undescribed lanostane-type triterpenoids, including three triterpenoids with a γ-lactone ring, namely applanlactones A‒C, four highly oxygenated lanostane triterpenoids, namely methyl applaniate A and applanoic acids B‒D, as well as five C21 nortriterpenoids, applanones A‒E were isolated from the fruiting bodies of Ganoderma applanatum (Pers.) Pat.. Their structures were elucidated by 1D, 2D NMR and MS spectra, as well as X-ray crystallographic analyses. Meanwhile, applanlactone A, methyl applaniate A and applanoic acid B showed inhibitory effects for the proliferation of hepatic stellate cells (HSCs) induced by transforming growth factor-β1 (TGF-β1) in vitro.

Protective Effect of Phaleria macrocarpa Water Extract (Proliverenol) against Carbon Tetrachloride-Induced Liver Fibrosis in Rats: Role of TNF-α and TGF-β1

Phaleria macrocarpa is one of the Indonesian herbal plants which has been shown to have a hepatoprotective effect. This study was conducted to evaluate the protective effect of water extract of mahkota dewa (Phaleria macrocarpa) in liver fibrosis and to elucidate its mechanism of action. Male Sprague-Dawley rats were treated with carbon tetrachloride (CCl₄) for 8 weeks to induce liver fibrosis. Rats were randomly divided into 6 groups (n=5), i.e., control group, CCl4 group, CCl4 + NAC group, CCl4 + various doses of water extract of Phaleria macrocarpa (50, 100, and 150 mg/kg body weight). Aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), liver histopathology, malondialdehyde (MDA), ratio GSH/GSSG, Tumor Necrosis Factor- (TNF-) α, and Transforming Growth Factor- (TGF-) β ₁ were analyzed. This study demonstrated that water extract of Phaleria macrocarpa and NAC significantly protected CCl₄-induced liver injury as demonstrated by reduced AST, ALT, ALP, and fibrosis percentage compared with the CCl₄-only group. In addition, water extract of Phaleria macrocarpa and NAC significantly reduced the levels of MDA, TNF-α, and TGF-β ₁ as well as increasing the ratio of GSH/GSSG. Water extract of Phaleria macrocarpa prevents CCl₄-induced fibrosis in rats. The prevention of liver fibrosis was at least in part through its antioxidant and anti-inflammatory activities and through its capacity to inhibit hepatic stellate cells (HSC) activation by reducing fibrogenic cytokine TGF-β ₁.

Mononuclear phagocyte system in hepatitis C virus infection

The mononuclear phagocyte system (MPS), which consists of monocytes, dendritic cells (DCs), and macrophages, plays a vital role in the innate immune defense against pathogens. Hepatitis C virus (HCV) is efficient in evading the host immunity, thereby facilitating its development into chronic infection. Chronic HCV infection is the leading cause of end-stage liver diseases, liver cirrhosis, and hepatocellular carcinoma. Acquired immune response was regarded as the key factor to eradicate HCV. However, innate immunity can regulate the acquired immune response. Innate immunity-derived cytokines shape the adaptive immunity by regulating T-cell differentiation, which determines the outcome of acute HCV infection. Inhibition of HCV-specific T-cell responses is one of the most important strategies for immune system evasion. It is meaningful to illustrate the role of innate immune response in HCV infection. With the MPS being the important factor in innate immunity, therefore, understanding the role of the MPS in HCV infection will shed light on the pathophysiology of chronic HCV infection. In this review, we outline the impact of HCV infection on the MPS and cytokine production. We discuss how HCV is detected by the MPS and describe the function and impairment of MPS components in HCV infection.

Evaluation of elastography combined with serological indexes for hepatic fibrosis in patients with chronic hepatitis B

AIM

To investigate the value of ultrasound elastography combined with serological indexes in diagnosing liver fibrosis and assessing its severity.

METHODS

A total of 338 chronic hepatitis B (CHB) patients were divided into a disease group (patients with hepatic fibrosis) and control group (subjects without hepatic fibrosis). The disease group was further divided into S1-S4 according to the degree of fibrosis. Independent risk factors for hepatic fibrosis were analyzed using multivariate logistic regression. The diagnostic values of hepatic fibrosis from different indicators were compared using receiver operating characteristic (ROC) curves. The combination of elastography and serological indexes was explored to assess the severity of hepatic fibrosis.

RESULTS

The multivariate logistic regression analysis results revealed that shear wave velocity (SWV), hyaluronic acid (HA), type IV collagen (CIV) and aspartate aminotransferase-to-platelet ratio index (APRI) significantly affected the occurrence of hepatic fibrosis. The ROC curve revealed that the accuracy of the diagnosis of hepatic fibrosis for SWV and HA were 87.3% and 84.8%, respectively. The accuracy of SWV combined with HA was 88.9%. The multiple linear regression analysis revealed that SWV, aspartate aminotransferase (AST)/alanine aminotransferase (ALT), HA, CIV, APRI and fibrosis index based on the 4 factor (FIB-4) were screened as statistically significant independent factors. The established regression equation was: Fibrosis level = -4.046 + 1.024 × SWV + 1.170 × AST/ALT + 0.011 × HA + 0.020 × CIV + 0.719 × APRI + 0.379 × FIB-4.

CONCLUSION

SWV combined with serological indexes can improve the accuracy of diagnosis for CHB hepatic fibrosis. Serum indexes can help diagnose the degree of hepatic fibrosis.

AAV serotype 8-mediated liver specific GNMT expression delays progression of hepatocellular carcinoma and prevents carbon tetrachloride-induced liver damage

Glycine N-methyltransferase (GNMT) is abundantly expressed in normal livers and plays a protective role against tumor formation. GNMT depletion leads to progression of hepatocellular carcinoma (HCC). In this study, we investigated the activity of ectopic GNMT delivered using recombinant adeno-associated virus (AAV) gene therapy in mouse models of liver cirrhosis and HCC. Injection of AAV serotype 8 (AAV8) vector carrying the GNMT gene (AAV8-GNMT) in Gnmt^−/− mice increased GNMT expression and downregulated pro-inflammatory responses, resulting in reduced liver damage and incidence of liver tumors. Moreover, AAV8-GNMT resulted in the amelioration of carbon tetrachloride (CCl₄)-induced liver fibrosis in BALB/c mice. We showed that AAV8-GNMT protected hepatocytes from CCl₄-induced liver damage.  AAV8-GNMT significantly attenuated the levels of pro-fibrotic markers and increased efficiency of hepatocyte proliferation. These results suggest that correction of hepatic GNMT by gene therapy of AAV8-mediated gene enhancement may provide a potential strategy for preventing and delaying development of liver diseases.