Target For Liver Disease Research Articles

Abstract 5330: Intestine-specific homeobox edits macrophage polarization in the disease microenvironment by activating inflammasome activity

Abstract Inflammasome activity has a pivotal role in the innate immune system, highlighting its importance in the development of various inflammatory diseases, including cancers. However, the specific impact of inflammasome-produced cytokines from tumor cells on disease progression remains uncertain. In this study, we show that the expression levels of inflammasome-related genes (NLRP1 and NLRP3), combined with levels of the intestine-specific homeobox (ISX), significantly correlate with factors like lesion count, disease stage, and lymph vascular invasion. Tumor cells enhance the secretion of key cytokines such as IL-1β and IL-18, exacerbating disease progression via the ISX-TWIST1 complex. In terms of mechanism, transcriptomic analysis and molecular evidence reveal that ISX interacts with the basic helix-loop-helix (bHLH) domain of TWIST1 through its homeobox domain. This interaction forms a transcriptional complex that activates inflammasomes by directly binding to the conserved sequence "-GGDWYR-" in promoter regions of several NF-κB and inflammasome-related genes (NFKBs, RELs, NLRP1, NLRP3, NEK7, AIM2, and ASC). Elevated levels of IL-18, induced by active inflammasomes, lead to the shift of M0 macrophages into the M2-like phenotype within the hepatic microenvironment. In mice with liver-specific ISX mutations, inflammasome-related genes and activities were eliminated, stopping disease progression in an acute hepatic disease model. These findings underscore the critical role of the ISX-TWIST1 complex in liver disease and tumor progression on both mechanistic and clinical levels. They also offer new insights for potential preventive and therapeutic targets in liver disease. Citation Format: Li-Ting Wang, Shih-Hsien Hsu. Intestine-specific homeobox edits macrophage polarization in the disease microenvironment by activating inflammasome activity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5330.

GAS6/TAM Axis as Therapeutic Target in Liver Diseases.

TAM (TYRO3, AXL, and MERTK) protein tyrosine kinase membrane receptors and their vitamin K-dependent ligands GAS6 and protein S (PROS) are well-known players in tumor biology and autoimmune diseases. In contrast, TAM regulation of fibrogenesis and the inflammation mechanisms underlying metabolic dysfunction-associated steatohepatitis (MASH), cirrhosis, and, ultimately, liver cancer has recently been revealed. GAS6 and PROS binding to phosphatidylserine exposed in outer membranes of apoptotic cells links TAMs, particularly MERTK, with hepatocellular damage. In addition, AXL and MERTK regulate the development of liver fibrosis and inflammation in chronic liver diseases. Acute hepatic injury is also mediated by the TAM system, as recent data regarding acetaminophen toxicity and acute-on-chronic liver failure have uncovered. Soluble TAM-related proteins, mainly released from activated macrophages and hepatic stellate cells after hepatic deterioration, are proposed as early serum markers for disease progression. In conclusion, the TAM system is becoming an interesting pharmacological target in liver pathology and a focus of future biomedical research in this field.

GepLiver: an integrative liver expression atlas spanning developmental stages and liver disease phases

Chronic liver diseases usually developed through stepwise pathological transitions under the persistent risk factors. The molecular changes during liver transitions are pivotal to improve liver diagnostics and therapeutics yet still remain elusive. Cumulative large-scale liver transcriptomic studies have been revealing molecular landscape of various liver conditions at bulk and single-cell resolution, however, neither single experiment nor databases enabled thorough investigations of transcriptomic dynamics along the progression of liver diseases. Here we establish GepLiver, a longitudinal and multidimensional liver expression atlas integrating expression profiles of 2469 human bulk tissues, 492 mouse samples, 409,775 single cells from 347 human samples and 27 liver cell lines spanning 16 liver phenotypes with uniformed processing and annotating methods. Using GepLiver, we have demonstrated dynamic changes of gene expression, cell abundance and crosstalk harboring meaningful biological associations. GepLiver can be applied to explore the evolving expression patterns and transcriptomic features for genes and cell types respectively among liver phenotypes, assisting the investigation of liver transcriptomic dynamics and informing biomarkers and targets for liver diseases.

Ferroptosis as an emerging therapeutic target in liver diseases.

Ferroptosis is an iron-dependently nonapoptotic cell death characterized by excessive accumulation of lipid peroxides and cellular iron metabolism disturbances. Impaired iron homeostasis and dysregulation of metabolic pathways are contributors to ferroptosis. As a major metabolic hub, the liver synthesizes and transports plasma proteins and endogenous fatty acids. Also, it acts as the primary location of iron storage for hepcidin generation and secretion. To date, although the intricate correlation between ferroptosis and liver disorders needs to be better defined, there is no doubt that ferroptosis participates in the pathogenesis of liver diseases. Accordingly, pharmacological induction and inhibition of ferroptosis show significant potential for the treatment of hepatic disorders involved in lipid peroxidation. In this review, we outline the prominent features, molecular mechanisms, and modulatory networks of ferroptosis and its physiopathologic functions in the progression of liver diseases. Further, this review summarizes the underlying mechanisms by which ferroptosis inducers and inhibitors ameliorate liver diseases. It is noteworthy that natural active ingredients show efficacy in preclinical liver disease models by regulating ferroptosis. Finally, we analyze crucial concepts and urgent issues concerning ferroptosis as a novel therapeutic target in the diagnosis and therapy of liver diseases.

Eukaryotic Ribosomal Protein S5 of the 40S Subunit: Structure and Function

The ribosomal protein RPS5 is one of the prime proteins to combine with RNA and belongs to the conserved ribosomal protein family. It plays a substantial role in the process of translation and also has some non-ribosome functions. Despite the enormous studies on the relationship between the structure and function of prokaryotic RPS7, the structure and molecular details of the mechanism of eukaryotic RPS5 remain largely unexplored. This article focuses on the structure of RPS5 and its role in cells and diseases, especially the binding to 18S rRNA. The role of RPS5 in translation initiation and its potential use as targets for liver disease and cancer are discussed.

NOX as a Therapeutic Target in Liver Disease.

The nicotinamide adenine dinucleotide phosphate hydrogen oxidase (NADPH oxidase or NOX) plays a critical role in the inflammatory response and fibrosis in several organs such as the lungs, pancreas, kidney, liver, and heart. In the liver, NOXs contribute, through the generation of reactive oxygen species (ROS), to hepatic fibrosis by acting through multiple pathways, including hepatic stellate cell activation, proliferation, survival, and migration of hepatic stellate cells; hepatocyte apoptosis, enhancement of fibrogenic mediators, and mediation of an inflammatory cascade in both Kupffer cells and hepatic stellate cells. ROS are overwhelmingly produced during malignant transformation and hepatic carcinogenesis (HCC), creating an oxidative microenvironment that can cause different and various types of cellular stress, including DNA damage, ER stress, cell death of damaged hepatocytes, and oxidative stress. NOX1, NOX2, and NOX4, members of the NADPH oxidase family, have been linked to the production of ROS in the liver. This review will analyze some diseases related to an increase in oxidative stress and its relationship with the NOX family, as well as discuss some therapies proposed to slow down or control the disease’s progression.

The role of ZNF143 overexpression in rat liver cell proliferation

BackgroundZinc finger protein 143(ZNF143), a member of the Krüppel C2H2-type zinc finger protein family, is strongly associated with cell cycle regulation and cancer development. A recent study suggested that ZNF143 plays as a transcriptional activator that promotes hepatocellular cancer (HCC) cell proliferation and cell cycle transition. However, the exact biological role of ZNF143 in liver regeneration and normal liver cell proliferation has not yet been investigated.MethodsIn our study, we constructed a stable rat liver cell line (BRL-3A) overexpressing ZNF143 and then integrated RNA-seq and Cleavage Under Targets and Tagmentation (CUT&Tag) data to identify the mechanism underlying differential gene expression.ResultsOur results show that ZNF143 expression is upregulated during the proliferation phase of liver regeneration after 2/3 partial hepatectomy (PH). The cell counting kit-8 (CCK-8) assay, EdU staining and RNA-seq data analyses revealed that ZNF143 overexpression (OE) significantly inhibited BRL-3A cell proliferation and cell cycle progression. We then performed CUT&Tag assays and found that approximately 10% of ZNF143-binding sites (BSs) were significantly changed genome-wide by ZNF143 OE. However, CCCTC-binding factor (CTCF) binding to chromatin was not affected. Interestingly, the integration analysis of RNA-seq and CUT&Tag data showed that some of genes affected by ZNF143 differential BSs are in the center of each gene regulation module. Gene ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses indicated that these genes are critical in the maintenance of cell identity.ConclusionThese results indicated that the expression level of ZNF143 in the liver is important for the maintenance of cell identity. ZNF143 plays different roles in HCC and normal liver cells and may be considered as a potential therapeutic target in liver disease.

MiR-223 as a Regulator and Therapeutic Target in Liver Diseases.

MicroRNAs (miRNAs) are endogenous non-coding single-stranded small molecule RNAs consisting of 20–24 nucleotides that are highly conserved in species evolution. Expression of miRNAs is strictly tissue-specific, and it is chronological in fungi and plants, as well as in animals. MiR-223 has been shown to play a key role in innate immunity, and dysregulation of its expression contributes to the pathogenesis of multiple inflammatory diseases, and cancers. In this article the biosynthesis and functions of miR-223 in innate immunity are reviewed, and the role of miR-223 in liver physiopathology and therapeutic prospects are highlighted.

Ischemia/Reperfusion Injury of Fatty Liver Is Protected by A2AR and Exacerbated by A1R Stimulation through Opposite Effects on ASK1 Activation.

Hepatic ischemia/reperfusion injury (IRI) is aggravated by steatosis and is a main risk factor in fatty liver transplantation. Adenosine receptors (ARs) are emerging as therapeutic targets in liver diseases. By using cellular and in vivo systems of hepatic steatosis and IRI, here we evaluated the effects of pharmacological A2AR and A1R activation. The A2AR agonist CGS21680 protected the primary steatotic murine hepatocyte from IR damage and the activation of ASK1 and JNK. Such an effect was attributed to a phosphatidylinositol-3-kinase (PI3K)/Akt-dependent inhibition of ASK1. By contrast, the A1R agonist CCPA enhanced IR damage, intracellular steatosis and oxidative species (OS) production, thereby further increasing the lipid/OS-dependent ASK1-JNK stimulation. The CGS2680 and CCPA effects were nullified by a genetic ASK1 downregulation in steatotic hepatoma C1C7 cells. In steatotic mice livers, CGS21680 protected against hepatic IRI and ASK1/JNK activation whereas CCPA aggravated hepatic steatosis and IRI, and enhanced ASK1 and JNK stimulation. These results evidence a novel mechanism of CGS21680-mediated hepatoprotection, i.e., the PI3K/AKT-dependent inhibition of ASK1, and they show that CGS21680 and CCPA reduces and enhances the IRI of fatty liver, respectively, by preventing or increasing the activation of the cytotoxic ASK1/JNK axis. They also indicate the selective employment of A2AR agonists as an effective therapeutic strategy to prevent IRI in human fatty liver surgery.

PPARs as Metabolic Sensors and Therapeutic Targets in Liver Diseases

Carbohydrates and lipids are two components of the diet that provide the necessary energy to carry out various physiological processes to help maintain homeostasis in the body. However, when the metabolism of both biomolecules is altered, development of various liver diseases takes place; such as metabolic-associated fatty liver diseases (MAFLD), hepatitis B and C virus infections, alcoholic liver disease (ALD), and in more severe cases, hepatocelular carcinoma (HCC). On the other hand, PPARs are a family of ligand-dependent transcription factors with an important role in the regulation of metabolic processes to hepatic level as well as in other organs. After interaction with specific ligands, PPARs are translocated to the nucleus, undergoing structural changes to regulate gene transcription involved in lipid metabolism, adipogenesis, inflammation and metabolic homeostasis. This review aims to provide updated data about PPARs’ critical role in liver metabolic regulation, and their involvement triggering the genesis of several liver diseases. Information is provided about their molecular characteristics, cell signal pathways, and the main pharmacological therapies that modulate their function, currently engaged in the clinic scenario, or in pharmacological development.

Histone deacetylase‑2: A potential regulator and therapeutic target in liver disease (Review).

Histone acetyltransferases are responsible for histone acetylation, while histone deacetylases (HDACs) counteract histone acetylation. An unbalanced dynamic between histone acetylation and deacetylation may lead to aberrant chromatin landscape and chromosomal function. HDAC2, a member of class I HDAC family, serves a crucial role in the modulation of cell signaling, immune response and gene expression. HDAC2 has emerged as a promising therapeutic target for liver disease by regulating gene transcription, chromatin remodeling, signal transduction and nuclear reprogramming, thus receiving attention from researchers and clinicians. The present review introduces biological information of HDAC2 and its physiological and biochemical functions. Secondly, the functional roles of HDAC2 in liver disease are discussed in terms of hepatocyte apoptosis and proliferation, liver regeneration, hepatocellular carcinoma, liver fibrosis and non-alcoholic steatohepatitis. Moreover, abnormal expression of HDAC2 may be involved in the pathogenesis of liver disease, and its expression levels and pharmacological activity may represent potential biomarkers of liver disease. Finally, research on selective HDAC2 inhibitors and non-coding RNAs relevant to HDAC2 expression in liver disease is also reviewed. The aim of the present review was to improve understanding of the multifunctional role and potential regulatory mechanism of HDAC2 in liver disease.

Free Fatty Acid Receptors as Mediators and Therapeutic Targets in Liver Disease.

Free fatty acid receptors (FFARs) are a class of G protein-coupled receptors (GPCRs) that have wide-ranging effects on human physiology. The four well-characterized FFARs are FFAR1/GPR40, FFAR2/GPR43, FFAR3/GPR41, and FFAR4/GPR120. Short-chain (<6 carbon) fatty acids target FFAR2/GPR43 and FFAR3/GPR41. Medium- and long-chain fatty acids (6–12 and 13–21 carbon, respectively) target both FFAR1/GPR40 and FFAR4/GPR120. Signaling through FFARs has been implicated in non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), intestinal failure-associated liver disease (IFALD), and a variety of other liver disorders. FFARs are now regarded as targets for therapeutic intervention for liver disease, diabetes, obesity, hyperlipidemia, and metabolic syndrome. In this review, we provide an in-depth, focused summary of the role FFARs play in liver health and disease.

The Roles of Neutrophils in the Pathogenesis of Liver Diseases.

Neutrophils are the largest population of circulating leukocytes and the first responder against invading pathogens or other danger signals. Sophisticated machineries help them play critical roles in immunity and inflammation, including phagocytosis, superoxide production, cytokine and chemokine production, degranulation, and formation of neutrophil extracellular traps (NETs). After maturation and release from the bone marrow, neutrophils migrate to inflamed tissues in response to many stimuli. Increasing evidences indicate that neutrophils are critically involved in the pathogenesis of liver diseases, including liver cancer, thus making them promising target for the treatment of liver diseases. Here, we would like to provide the latest finding about the role of neutrophils in liver diseases and discuss the potentiality of neutrophils as target for liver diseases.

Non-coding RNA crosstalk with nuclear receptors in liver disease

The dysregulation of nuclear receptors (NRs) underlies the pathogenesis of a variety of liver disorders. Non-coding RNAs (ncRNAs) are defined as RNA molecules transcribed from DNA but not translated into proteins. MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are two types of ncRNAs that have been extensively studied for regulating gene expression during diverse cellular processes. NRs as therapeutic targets in liver disease have been exemplified by the successful application of their pharmacological ligands in clinics. MiRNA-based reagents or drugs are emerging as flagship products in clinical trials. Advancing our understanding of the crosstalk between NRs and ncRNAs is critical to the development of diagnostic and therapeutic strategies. This review summarizes recent findings on the reciprocal regulation between NRs and ncRNAs (mainly on miRNAs and lncRNAs) and their implication in liver pathophysiology, which might be informative to the translational medicine of targeting NRs and ncRNAs in liver disease.

Netting Liver Disease: Neutrophil Extracellular Traps in the Initiation and Exacerbation of Liver Pathology.

The liver plays a vital role in the immune system. Its unique position in the portal circulation and the architecture of the hepatic sinusoids, in combination with the wide-ranged population of immunocompetent cells, make the liver function as an immune filter. To aid in pathogen clearance, once challenged, the liver initiates the rapid recruitment of a wide variety of inflammatory cells, including neutrophils. These neutrophils, in conjunction with platelets, facilitate the release of neutrophil extracellular traps (NETs), which are web-like structures of decondensed nuclear DNA, histones, and neutrophil proteins. NETs function as both a physical and a chemical barrier, binding and killing pathogens circulating in the blood stream. In addition to their antimicrobial role, NETs also bind platelets, activate coagulation, and exacerbate host inflammatory response. This interplay between inflammation and coagulation drives microvascular occlusion, ischemia, and (sterile) damage in liver disease. Although direct clinical evidence of this interplay is scarce, preliminary studies indicate that NETs contribute to progression of liver disease and (thrombotic) complications. Here, we provide an overview of the pathological mechanisms of NETs in liver disease. In addition, we summarize clinical evidence for NETs in different disease etiologies and complications of liver disease and discuss the possible implications for the use of NETs as a diagnostic marker and a therapeutic target in liver disease.

Matrix Metalloproteinases as Potential Biomarkers and Therapeutic Targets in Liver Diseases.

Chronic liver diseases, characterized by an excessive accumulation of extracellular matrix (ECM) resulting in scar tissue formation, are a growing health problem causing increasing morbidity and mortality worldwide. Currently, therapeutic options for tissue fibrosis are severely limited, and organ transplantation is the only treatment for the end-stage liver diseases. During liver damage, injured hepatocytes release proinflammatory factors resulting in the recruitment and activation of immune cells that activate quiescent hepatic stellate cells (HSCs). Upon activation, HSCs transdifferentiate into highly proliferative, migratory, contractile and ECM-producing myofibroblasts. The disrupted balance between ECM deposition and degradation leads to the formation of scar tissue referred to as fibrosis. This balance can be restored either by reducing ECM deposition (by inhibition of HSCs activation and proliferation) or enhancing ECM degradation (by increased expression of matrix metalloproteinases (MMPs)). MMPs play an important role in ECM remodeling and represent an interesting target for therapeutic drug discovery. In this review, we present the current knowledge about ECM remodeling and role of the different MMPs in liver diseases. MMP expression patterns in different stages of liver diseases have also been reviewed to determine their role as biomarkers. Finally, we highlight MMPs as promising therapeutic targets for the resolution of liver diseases.

MicroRNA-122 promotes cardiomyocyte hypertrophy via targeting FoxO3

Objective—microRNAs (miRNAs) have emerged as novel regulators for cardiac hypertrophy. MiR-122 is well recognized as a promising therapeutic target in liver disease, whereas recently plays important roles in cardiovascular diseases. The current study aimed to explore the effect of miR-122 on the pathogenesis of cardiomyocyte hypertrophy. Methods and results—The cardiomyocytes isolated from the neonatal rat ventricular cardiomyocytes (NRVMs) were collected and performed to Angiotensin II (Ang II) administration. We observed a dramatically increased miR-122 expression in hypertrophic cardiomyocytes. The NRVMs transfected with miR-122 mimic or negative control were utilized for the functional analysis. Overexpression of miR-122 increased the morphology size of cardiomyocytes and promoted the pro-hypertrophic genes expression, whereas downregulated the anti-hypertrophic genes upon Ang II stimulation. The bioinformatics analysis and luciferase reporter assays exhibited that miR-122 directly targeted FoxO3 and attenuated its gene level in hypertrophic cardiomyocytes. Moreover, miR-122 negatively regulated FoxO3 but promoted calcineurin signaling pathway activation. Importantly, FoxO3 overexpression significantly reversed the effect of miR-122 on cardiomyocyte hypertrophy. Conclusion—Collected, our finding demonstrated that miR-122 accelerated the development of cardiomyocytes hypertrophy partially via directly regulation of FoxO3-calcineurin pathway.

Vascular Targets for the Treatment of Portal Hypertension.

Portal hypertension is the main driver for severe complications in patients with liver cirrhosis. With improved understanding of molecular pathways that promote hepatic vascular remodeling, vasoconstriction, and sinusoidal capillarization potential vascular targets for the treatment of portal hypertension have been identified. Inhibition of vascular endothelial and platelet-derived growth factors-driven angiogenesis has been shown to reduce portal pressure and decrease hepatic inflammation. Angiopoietin/Tie signaling represents additional promising vascular targets in liver disease. The eNOS-NO-sGC-cGMP pathway modulates sinusoidal vasoconstriction and capillarization. Nuclear farnesoid X receptor (FXR) agonists decrease intrahepatic vascular resistance by inhibition of fibrogenesis and sinusoidal remodeling. Statins ameliorate endothelial dysfunction, decrease portal pressure, and reduce fibrogenesis. Anticoagulation with low-molecular heparin or anti-Xa inhibitors improved portal hypertension by deactivation of hepatic stellate cells and potentially via reduction of sinusoidal microthrombosis. This review summarizes important vascular targets for treatment of portal hypertension that have shown promising results in experimental studies.

Integrated Approaches for Identifying Molecular Targets in Liver Disease

Integrated Approaches for Identifying Molecular Targets in Liver Disease

Chemokine (C-C motif) ligand 2 gene ablation protects low-density lipoprotein and paraoxonase-1 double deficient mice from liver injury, oxidative stress and inflammation

The risk of non-alcoholic fatty liver disease increases with obesity. Vulnerability to oxidative stress and/or inflammation represents a crucial step in non-alcoholic fatty liver disease progression through abnormal metabolic responses. In this study, we investigated the role of CCL2 gene ablation in mice that were double deficient in low density lipoprotein receptor and in paraoxonase-1. Mass spectrometry methods were used to assess the liver metabolic response in mice fed either regular chow or a high-fat diet. Dietary fat caused liver steatosis, oxidative stress and the accumulation of pro-inflammatory macrophages in the livers of double deficient mice. We observed alterations in energy metabolism-related pathways and in metabolites associated with the methionine cycle and the glutathione reduction pathway. This metabolic response was associated with impaired autophagy. Conversely, when we established CCL2 deficiency, histologic features of fatty liver disease were abrogated, hepatic liver oxidative stress decreased, and anti-inflammatory macrophage marker expression levels increased. These changes were associated with the normalization of metabolic disturbances and increased lysosome-associated membrane protein 2, expression, which suggests enhanced chaperone-mediated autophagy. This study demonstrates that CCL2 is a key molecule for the development of metabolic and histological alterations in the liver of mice sensitive to the development of hyperlipidemia and hepatic steatosis, a finding with potential to identify new therapeutic targets in liver diseases.