Emricasan (IDN-6556) Lowers Portal Pressure in Patients With Compensated Cirrhosis and Severe Portal Hypertension

Therapeutic Potential of Emricasan, a Pan-Caspase Inhibitor, in Reducing Cell Death and Extracellular Matrix Accumulation in Fuchs Endothelial Corneal Dystrophy

Fuchs endothelial corneal dystrophy (FECD) is a progressive disorder characterized by endothelial cell loss and excessive extracellular matrix (ECM) accumulation leading to corneal dysfunction. Emricasan, a pan-caspase inhibitor, was investigated for its therapeutic potential in suppressing these pathological changes. Patient-derived FECD cells and stress-induced cell models were treated with emricasan to assess its effects on apoptosis and ECM production. Caspase-specific knockdown experiments were performed to identify key mediators. Col8a2Q455K/Q455K mice, model mice of early-onset FECD, received twice-daily administration of 0.1% emricasan eye drops from 8 to 28 weeks of age. Endothelial cell density, hexagonality, cell size variation, and guttae area were evaluated by contact specular microscopy, while transcriptomic changes were analyzed via RNA sequencing. Emricasan effectively reduced apoptosis and ECM production in vitro by selectively inhibiting caspase-7 without affecting canonical TGF-β signaling. In vivo, emricasan-treated mice exhibited significantly higher endothelial cell density, improved hexagonality, and reduced variation in cell size compared with controls. Transcriptome analysis revealed distinct gene expression changes in the corneal endothelium following emricasan treatment. These findings suggest that emricasan exerts dual protective effects by inhibiting caspase-7-mediated ECM accumulation and broadly suppressing apoptosis, highlighting its potential as a pharmacological therapy for FECD.

Pan-caspase inhibitors induce secretion of HIV-1 latency reversal agent lymphotoxin-alpha from cytokine-primed NK cells

The persistence of HIV-1 latency reservoirs in CD4+ T cells is a significant obstacle for curing HIV-1. Shock-and-kill strategies, which aim to reactivate latent HIV-1 followed by cytotoxic clearance, have shown limited success in vivo due to insufficient efficacy of latency reversal agents (LRAs) and off-target effects. Natural killer (NK) cells, with their ability to mediate cytotoxicity independent of antigen specificity, offer a promising avenue for enhancing the shock-and-kill approach. Previously, we observed that pan-caspase inhibitors induce NK cells to secrete an LRA in vitro. Here, we aimed to identify this LRA using a targeted proteomic approach. We identified lymphotoxin-α (LTα) as the key LRA secreted by NK cells following pan-caspase inhibitor treatment. LTα was shown to significantly induce HIV-1 LTR promoter activity, a hallmark of viral reactivation. Neutralization of LTα effectively abolished the observed LRA activity, confirming its central role. Moreover, cytokine-primed but not resting human primary NK cells exhibited LRA activity that could be neutralized with LTα neutralizing antibodies. Finally, pan-caspase inhibitor treatment did not decrease the ability of the cytokine-primed NK cells to kill target cells. These findings demonstrate that cytokine-primed NK cells, through LTα secretion, can effectively reactivate latent HIV-1 following pan-caspase inhibitor treatment, without compromising NK cell cytotoxicity. This highlights a potential enhancement strategy utilizing NK cells for shock-and-kill approaches in HIV-1 cure research.

From Pathophysiology to Practice: Evolving Pharmacological Therapies, Clinical Complications, and Pharmacogenetic Considerations in Portal Hypertension

Background: Portal hypertension is a major complication of chronic liver diseases, leading to serious issues such as esophageal variceal bleeding. The increase in portal vein pressure is driven by both an organic component and a functional component, including tonic contraction of hepatic stellate cells. These processes result in a pathological rise in intrahepatic vascular resistance, stemming from partial impairment of hepatic microcirculation, which is further exacerbated by abnormalities in extrahepatic vessels, including increased portal blood flow. Objectives: This review aims to provide a comprehensive overview of the evolving pharmacological therapies for portal hypertension, with consideration and discussion of pathophysiological mechanisms, clinical complications, and pharmacogenetic considerations, highlighting potential directions for future research. Methods: A review of recent literature was performed to evaluate current knowledge and potential therapeutic strategies in portal hypertension. Results: For over 35 years, non-selective beta-blockers have been the cornerstone therapy for portal hypertension by reducing portal vein inflow as an extrahepatic target, effectively preventing decompensation and variceal hemorrhages. However, since not all patients exhibit an adequate response to non-selective beta-blockers (NSBBs), and some may not tolerate NSBBs, alternative or adjunctive therapies that enhance the effects of NSBBs on portal pressure are being investigated in preclinical and early clinical studies. Conclusions: A better understanding of pharmacogenetic factors and pathophysiological mechanisms could lead to more individualized and effective treatments for portal hypertension. These insights highlight potential directions for future research.

Recent advances in promising drugs for primary prevention of gastroesophageal variceal bleeding with cirrhotic portal hypertension

BACKGROUND

Gastroesophageal variceal bleeding is one of the most severe complications of patients with cirrhosis. Although primary prevention drugs, including non-selective β-blockers, have effectively reduced the incidence of bleeding, their efficacy is limited due to side effects and related contraindications. With recent advances in precision medicine, precise drug treatment provides better treatment efficacy.

DATA SOURCES

Literature search was conducted in PubMed, MEDLINE and Web of Science for relevant articles published up to May 2022. Information on clinical trials was obtained from https://clinicaltrials.gov/ and http://www.chictr.org.cn/.

RESULTS

The in-depth understanding of the pathogenesis and advances of portal hypertension has enabled the discovery of multiple molecular targets for promising drugs. According to the site of action, these drugs could be classified into four classes: intrahepatic, extrahepatic, both intrahepatic and extrahepatic targets and others. All these classes of drugs offer advantages over traditional treatments in prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.

CONCLUSIONS

This review classified and summarized the promising drugs, which prevent gastroesophageal variceal bleeding by targeting specific markers of pathogenesis of portal hypertension, demonstrating the significance of using the precision medicine strategy to discover and develop promising drugs for the primary prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.

Current investigations for liver fibrosis treatment: between repurposing the FDA-approved drugs and the other emerging approaches

Long-term liver injuries lead to hepatic fibrosis, often progressing into cirrhosis, liver failure, portal hypertension, and hepatocellular carcinoma. There is currently no effective therapy available for liver fibrosis. Thus, continuous investigations for anti-fibrotic therapy are ongoing. The main theme of anti-fibrotic investigation during recent years is the rationale-based selection of treatment molecules according to the current understanding of the pathology of the disease. The research efforts are mainly toward repurposing current FDA-approved drugs targeting etiological molecular factors involved in developing liver fibrosis. In parallel, investigations also focus on experimental small molecules with evidence to hinder or reverse the fibrosis. Natural compounds, immunological, and genetic approaches have shown significant encouraging effects. This review summarizes the efficacy and safety of current under-investigation antifibrosis medications targeting various molecular targets, as well as the properties of antifibrosis medications, mainly in phase II and III clinical trials.

ROS/RNS as molecular signatures of chronic liver diseases

The liver can succumb to oxidant damage during the development of chronic liver diseases. Despite their physiological relevance to hepatic homeostasis, excessive reactive oxygen/nitrogen species (ROS/RNS) production under pathological conditions is detrimental to all liver constituents. Chronic oxidative stress coupled to unresolved inflammation sets in motion the activation of profibrogenic hepatic stellate cells (HSCs) and later pathogenesis of liver fibrosis, cirrhosis, and liver cancer. The liver antioxidant and repair systems, along with autophagic and ferroptotic machineries, are implicated in the onset and trajectory of disease development. In this review, we discuss the ROS/RNS-related mechanisms underlying liver fibrosis of distinct etiologies and highlight preclinical and clinical trials of antifibrotic therapies premised on remediating oxidative/nitrosative stress in hepatocytes or targeting HSC activation.

The Protective Effect of Nutraceuticals on Hepatic Ischemia-Reperfusion Injury in Wistar Rats

Nutraceuticals are bioactive compounds present in foods, utilized to ameliorate health, prevent diseases, and support the proper functioning of the human body. They have gained attention due to their ability to hit multiple targets and act as antioxidants, anti-inflammatory agents, and modulators of immune response and cell death. Therefore, nutraceuticals are being studied to prevent and treat liver ischemia-reperfusion injury (IRI). This study evaluated the effect of a nutraceutical solution formed by resveratrol, quercetin, omega-3 fatty acid, selenium, ginger, avocado, leucine, and niacin on liver IRI. IRI was performed with 60 min of ischemia and 4 h of reperfusion in male Wistar rats. Afterward, the animals were euthanized to study hepatocellular injury, cytokines, oxidative stress, gene expression of apoptosis-related genes, TNF-α and caspase-3 proteins, and histology. Our results show that the nutraceutical solution was able to decrease apoptosis and histologic injury. The suggested mechanisms of action are a reduction in gene expression and the caspase-3 protein and a reduction in the TNF-α protein in liver tissue. The nutraceutical solution was unable to decrease transaminases and cytokines. These findings suggest that the nutraceuticals used favored the protection of hepatocytes, and their combination represents a promising therapeutic proposal against liver IRI.

Targeting protein modifications in metabolic diseases: molecular mechanisms and targeted therapies

The ever-increasing prevalence of noncommunicable diseases (NCDs) represents a major public health burden worldwide. The most common form of NCD is metabolic diseases, which affect people of all ages and usually manifest their pathobiology through life-threatening cardiovascular complications. A comprehensive understanding of the pathobiology of metabolic diseases will generate novel targets for improved therapies across the common metabolic spectrum. Protein posttranslational modification (PTM) is an important term that refers to biochemical modification of specific amino acid residues in target proteins, which immensely increases the functional diversity of the proteome. The range of PTMs includes phosphorylation, acetylation, methylation, ubiquitination, SUMOylation, neddylation, glycosylation, palmitoylation, myristoylation, prenylation, cholesterylation, glutathionylation, S-nitrosylation, sulfhydration, citrullination, ADP ribosylation, and several novel PTMs. Here, we offer a comprehensive review of PTMs and their roles in common metabolic diseases and pathological consequences, including diabetes, obesity, fatty liver diseases, hyperlipidemia, and atherosclerosis. Building upon this framework, we afford a through description of proteins and pathways involved in metabolic diseases by focusing on PTM-based protein modifications, showcase the pharmaceutical intervention of PTMs in preclinical studies and clinical trials, and offer future perspectives. Fundamental research defining the mechanisms whereby PTMs of proteins regulate metabolic diseases will open new avenues for therapeutic intervention.

Apoptotic cell death in disease-Current understanding of the NCCD 2023

Apoptosis is a form of regulated cell death (RCD) that involves proteases of the caspase family. Pharmacological and genetic strategies that experimentally inhibit or delay apoptosis in mammalian systems have elucidated the key contribution of this process not only to (post-)embryonic development and adult tissue homeostasis, but also to the etiology of multiple human disorders. Consistent with this notion, while defects in the molecular machinery for apoptotic cell death impair organismal development and promote oncogenesis, the unwarranted activation of apoptosis promotes cell loss and tissue damage in the context of various neurological, cardiovascular, renal, hepatic, infectious, neoplastic and inflammatory conditions. Here, the Nomenclature Committee on Cell Death (NCCD) gathered to critically summarize an abundant pre-clinical literature mechanistically linking the core apoptotic apparatus to organismal homeostasis in the context of disease.

Metaflammation in glucolipid metabolic disorders: Pathogenesis and treatment

The public health issue of glucolipid metabolic disorders (GLMD) has grown significantly, posing a grave threat to human wellness. Its prevalence is rising yearly and tends to affect younger people. Metaflammation is an important mechanism regulating body metabolism. Through a complicated multi-organ crosstalk network involving numerous signaling pathways such as NLRP3/caspase-1/IL-1, NF-B, p38 MAPK, IL-6/STAT3, and PI3K/AKT, it influences systemic metabolic regulation. Numerous inflammatory mediators are essential for preserving metabolic balance, but more research is needed to determine how they contribute to the co-morbidities of numerous metabolic diseases. Whether controlling the inflammatory response can influence the progression of GLMD determines the therapeutic strategy for such diseases. This review thoroughly examines the role of metaflammation in GLMD and combs the research progress of related therapeutic approaches, including inflammatory factor-targeting drugs, traditional Chinese medicine (TCM), and exercise therapy. Multiple metabolic diseases, including diabetes, non-alcoholic fatty liver disease (NAFLD), cardiovascular disease, and others, respond therapeutically to anti-inflammatory therapy on the whole. Moreover, we emphasize the value and open question of anti-inflammatory-based means for treating GLMD.

Identification of novel prognostic biomarkers in the TF-enhancer-target regulatory network in hepatocellular carcinoma and immune infiltration analysis

Background: Hepatocellular carcinoma (HCC) remains notorious for its high malignancy, poor prognosis and high mortality. The exploration of novel therapeutic agents for HCC has remained challenging due to its complex aetiology. Therefore, it is necessary to elucidate the pathogenesis and mechanism of HCC for clinical intervention.

Methods: We collected data from several public data portals and systematically analysed the association between transcription factors (TFs), eRNA-associated enhancers and downstream targets. We next filtered the prognostic genes and established a novel prognosis-related nomogram model. Moreover, we explored the potential mechanisms of the identified prognostic genes. The expression level was validated by several ways.

Results: We first constructed a significant TF-enhancer-target regulatory network and identified DAPK1 as a coregulatory differentially expressed prognosis-related gene. We combined common clinicopathological factors and built a prognostic nomogram model for HCC. We found that our regulatory network was correlated with the processes of synthesizing various substances. Moreover, we explored the role of DAPK1 in HCC and found that it was associated with immune cell infiltration and DNA methylation. Several immunostimulators and targeting drugs could be promising immune therapy targets. The tumor immune microenvironment was analyzed. Finally, the lower DAPK1 expression in HCC was validated via the GEO database, UALCAN cohort, and qRT-PCR.

Conclusion: In conclusion, we established a significant TF-enhancer-target regulatory network and identified downregulated DAPK1 as an important prognostic and diagnostic gene in HCC. Its potential biological functions and mechanisms were annotated using bioinformatics tools.

The Role of Caspases in Alzheimer's Disease: Pathophysiology Implications and Pharmacologic Modulation

Alzheimer's disease (AD) is the most common neurodegenerative disorder worldwide. Although the main cause of the onset and development of AD is not known yet, neuronal death due to pathologic changes such as amyloid-β (Aβ) deposition, tau aggregation, neuroinflammation, oxidative stress, and calcium dyshomeostasis are considered to be the main cause. At the present, there is no cure for this insidious disorder. However, accurate identification of molecular changes in AD can help provide new therapeutic goals. Caspases are a group of proteases which are known because of their role in cellular apoptosis. In addition, different caspases are involved in other cellular responses to the environment, such as induction of inflammation. Emerging evidence suggest that these proteases play a central role in AD pathophysiology due to their role in the processing of amyloid-β protein precursor, tau cleavage, and neuroinflammation. Therefore, it seems that targeting caspases may be a suitable therapeutic option to slow the progression of AD. This review focuses on the role of caspases in AD pathophysiology and introduce results from studies targeted caspases in different models of AD.

New Insights of Early Brain Injury after Subarachnoid Hemorrhage: A Focus on the Caspase Family

Spontaneous subarachnoid hemorrhage (SAH), primarily caused by ruptured intracranial aneurysms, remains a prominent clinical challenge with a high rate of mortality and morbidity worldwide. Accumulating clinical trials aiming at the prevention of cerebral vasospasm (CVS) have failed to improve the clinical outcome of patients with SAH. Therefore, a growing number of studies have shifted focus to the pathophysiological changes that occur during the periods of early brain injury (EBI). New pharmacological agents aiming to alleviate EBI have become a promising direction to improve outcomes after SAH. Caspases belong to a family of cysteine proteases with diverse functions involved in maintaining metabolism, autophagy, tissue differentiation, regeneration, and neural development. Increasing evidence shows that caspases play a critical role in brain pathology after SAH. Therefore, caspase regulation could be a potential target for SAH treatment. Herein, we provide an overview pertaining to the current knowledge on the role of caspases in EBI after SAH, and we discuss the promising therapeutic value of caspase-related agents after SAH.

Natural killer cells induce HIV-1 latency reversal after treatment with pan-caspase inhibitors

The establishment of a latency reservoir is the major obstacle for a cure of HIV-1. The shock-and-kill strategy aims to reactivate HIV-1 replication in HIV -1 latently infected cells, exposing the HIV-1-infected cells to cytotoxic lymphocytes. However, none of the latency reversal agents (LRAs) tested so far have shown the desired effect in people living with HIV-1. We observed that NK cells stimulated with a pan-caspase inhibitor induced latency reversal in co-cultures with HIV-1 latently infected cells. Synergy in HIV-1 reactivation was observed with LRAs prostratin and JQ1. The supernatants of the pan-caspase inhibitor-treated NK cells activated the HIV-1 LTR promoter, indicating that a secreted factor by NK cells was responsible for the HIV-1 reactivation. Assessing changes in the secreted cytokine profile of pan-caspase inhibitor-treated NK cells revealed increased levels of the HIV-1 suppressor chemokines MIP1α (CCL3), MIP1β (CCL4) and RANTES (CCL5). However, these cytokines individually or together did not induce LTR promoter activation, suggesting that CCL3-5 were not responsible for the observed HIV-1 reactivation. The cytokine profile did indicate that pan-caspase inhibitors induce NK cell activation. Altogether, our approach might be-in combination with other shock-and-kill strategies or LRAs-a strategy for reducing viral latency reservoirs and a step forward towards eradication of functionally active HIV-1 in infected individuals.

Clinical Outcomes in Patients with Advanced Chronic Liver Disease and Hepatic Venous Pressure Gradient ≤ 10 mm Hg

BACKGROUND AND AIMS

Clinically significant portal hypertension (CSPH), defined as hepatic venous pressure gradient (HVPG) ≥ 10 mmHg predicts clinical decompensation (CD) in cirrhosis. A proportion of cirrhosis patients have HVPG 6-10 mmHg. Their natural history is largely unknown.

DESIGN

Consecutive patients with advanced chronic liver disease (aCLD) [histological cirrhosis(n = 196) or liver stiffness measurement (LSM) > 15 kPa(n = 65)] and HVPG 6-10 mmHg were included. Primary objective was to study their natural course and patterns of CD. We also analyzed the predictors of CD at presentation and on follow-up and response to carvedilol.

RESULTS

Of 261 patients with HVPG 6-10 mmHg, 129(49.4%) had CD at first presentation; 78(29.9%) had single and 51(19.5%) had ≥ 2 CD. The most common CDs were ascites(n = 77) and jaundice(n = 65). A baseline HVPG ≥ 8 mmHg was independently associated with greater risk of CD [HR:1.7; p-0.002, AUROC:0.85(95%CI-0.81-0.91)]. New CD developed in 14.4% patients with compensated aCLD (median duration-23.1 months). Despite comparable baseline HVPG, patients developing new CD had higher HVPG on follow-up(15.3 ± 3.7 vs. 8 ± 2.1 mmHg; p < 0.001). Baseline LSM > 26.6 kPa, portosystemic shunt and serum albumin independently predicted new CD. Overall HVPG response to carvedilol(n = 60) was 23.3%, independent of baseline CD and HVPG. Five-year mortality was higher with ≥ 2 CD compared to single or no CD (23.5, 10 and 3%, respectively; p < 0.001).

CONCLUSION

Nearly one-half of aCLD patients with HVPG 6-10 mmHg had CD, justifying the need to redefine CSPH. Interventions to reduce portal pressure in patients with HVPG ≥ 8 mmHg might improve long-term outcomes.

Current and investigational drugs in early clinical development for portal hypertension

Introduction

The development of portal hypertension leads to a majority of complications associated with chronic liver disease. Therefore, adequate treatment of portal hypertension is crucial in the management of such patients. Current treatment options are limited and consist mainly of medications that decrease the hyperdynamic circulation, such as non-selective beta blockers, and treatment of hypervolemia with diuretics. Despite these options, mortality rates have not improved over the last two decades. Newer, more effective treatment options are necessary to help improve survival and quality of life in these patients.

Areas covered

Multiple preclinical models and clinical studies have demonstrated potential efficacy of a variety of new treatment modalities. We introduce treatment options including the use of vasodilation promotors, vasoconstriction inhibitors, anticoagulants, antiangiogenics, and anti-inflammatory drugs. We examine the most recent studies for treatment options within these drug classes and offer insights as to which show the most promise in this field.

Methodology

Published studies that identified novel medical treatment options of portal hypertension were searched using PubMed (https://pubmed.ncbi.nlm.nih.gov/). Clinical trials listed in Clinicaltrials.gov were also searched with a focus on more recent and ongoing studies, including those with completed recruitment. Searching with key terms including "portal hypertension" as well as individually searching specific treatment medications that were listed in other publications was carried out. Finally, current societal guidelines and recent review articles relevant to the management of portal hypertension were evaluated, and listed references of interest were included.

Conclusion

Many ongoing early phase studies demonstrate promising results and may shape the field of portal hypertension management in future. As concrete results become available, larger RCTs will be required before making definitive conclusions regarding safety and efficacy and whether or not they can be incorporated into routine clinical practice. Statins, anticoagulants, and PDE inhibitors have been among the most studied and appear to be most promising.

Bioinformatic Data Mining for Candidate Drugs Affecting Risk of Bisphosphonate-Related Osteonecrosis of the Jaw (BRONJ) in Cancer Patients

Background. Bisphosphonate-related osteonecrosis of the jaw (BRONJ) leads to significant morbidity. Other coadministered drugs may modulate the risk for BRONJ. The present study aimed to leverage bioinformatic data mining to identify drugs that potentially modulate the risk of BRONJ in cancer. Methods. A GEO gene expression dataset of peripheral blood mononuclear cells related to BRONJ in multiple myeloma patients was downloaded, and differentially expressed genes (DEGs) in patients with BRONJ versus those without BRONJ were identified. A protein-protein interaction network of the DEGs was constructed using experimentally validated interactions in the STRING database. Overrepresented Gene Ontology (GO) molecular function terms and KEGG pathways in the network were analysed. Network topology was determined, and ‘hub genes’ with degree ≥2 in the network were identified. Known drug targets of the hub genes were mined from the ‘drug gene interaction database’ (DGIdb) and labelled as candidate drugs affecting the risk of BRONJ. Results. 751 annotated DEGs ( $\log \text{FC}\ge 1.5$ , $p<0.05$ ) were obtained from the microarray gene expression dataset GSE7116. A PPI network with 633 nodes and 168 edges was constructed. Data mining for drugs interacting with 49 gene nodes was performed. 37 drug interactions were found for 9 of the hub genes including TBP, TAF1, PPP2CA, PRPF31, CASP8, UQCRB, ACTR2, CFLAR, and FAS. Interactions were found for several established and novel anticancer chemotherapeutic, kinase inhibitor, caspase inhibitor, antiangiogenic, and immunomodulatory agents. Aspirin, metformin, atrovastatin, thrombin, androgen and antiandrogen drugs, progesterone, Vitamin D, and Ginsengoside 20(S)-Protopanaxadiol were also documented. Conclusions. A bioinformatic data mining strategy identified several anticancer, immunomodulator, and other candidate drugs that may affect the risk of BRONJ in cancer patients.

Investigational drugs in early clinical development for portal hypertension

INTRODUCTION

Advanced chronic liver disease is considered a reversible condition after removal of the primary aetiological factor. This has led to a paradigm shift in which portal hypertension (PH) is a reversible complication of cirrhosis. The pharmacologic management of PH is centered on finding targets to modify the natural history of cirrhosis and PH.

AREAS COVERED

This paper offers an overview of the use of pharmacological strategies in early clinical development that modify PH. Papers included were selected from searching clinical trials sites and PubMed from the last 10 years.

EXPERT OPINION

A paradigm shift has generated a new concept of PH in cirrhosis as a reversible complication of a potentially curable disease. Decreasing portal pressure to prevent decompensation and further complications of cirrhosis that may lead liver transplantation or death is a goal. Therapeutic strategies also aspire achieve total or partial regression of fibrosis thus eliminating the need for treatment or screening of PH.

New Drugs for Hepatic Fibrosis

The morbidity and mortality of hepatic fibrosis caused by various etiologies are high worldwide, and the trend is increasing annually. At present, there is no effective method to cure hepatic fibrosis except liver transplantation, and its serious complications threaten the health of patients and cause serious medical burdens. Additionally, there is no specific drug for the treatment of hepatic fibrosis, and many drugs with anti-hepatic fibrosis effects are in the research and development stage. Recently, remarkable progress has been made in the research and development of anti-hepatic fibrosis drugs targeting different targets. We searched websites such as PubMed, ScienceDirect, and Home-ClinicalTrials.gov and found approximately 120 drugs with anti-fibrosis properties, some of which are in phase Ⅱ or Ⅲ clinical trials. Additionally, although these drugs are effective against hepatic fibrosis in animal models, most clinical trials have shown poor results, mainly because animal models do not capture the complexity of human hepatic fibrosis. Besides, the effect of natural products on hepatic fibrosis has not been widely recognized at home and abroad. Furthermore, drugs targeting a single anti-hepatic fibrosis target are prone to adverse reactions. Therefore, currently, the treatment of hepatic fibrosis requires a combination of drugs that target multiple targets. Ten new drugs with potential for development against hepatic fibrosis were selected and highlighted in this mini-review, which provides a reference for clinical drug use.

Recombinant human thrombopoietin increases platelet count in severe thrombocytopenic patients with hepatitis B-related cirrhosis: Multicentre real-world observational study

Patients with hepatitis B-related cirrhosis complicated with thrombocytopenia have a higher risk of bleeding, which may lead to higher mortality. We aimed to explore the efficacy and safety of recombinant human thrombopoietin (rhTPO) in the treatment of hepatitis B-related cirrhosis complicated with severe thrombocytopenia. Patients with hepatitis B-related compensated liver cirrhosis complicated with severe thrombocytopenia were divided into four groups according to the treatment method for thrombocytopenia. Platelet counts, the appearance of bleeding symptoms and adverse events were evaluated during the observation period. Also during the observational period, the platelet counts in the prednisone group, rhTPO group and prednisone plus rhTPO group were higher than those in the no treatment group. Patients without splenomegaly reacted better to rhTPO. Fewer bleeding events of grade 2 or worse were observed in the three treatment groups compared to the no treatment group. The platelet counts at baseline and treatment with rhTPO and/or prednisone were factors associated with bleeding events of grade 2 or worse in multivariate analysis. There could be a potential advantage for the use of rhTPO plus prednisone based on higher platelet counts and fewer bleeding events. Treatment with rhTPO was more effective in patients without splenomegaly.

The impact of emricasan on chronic liver diseases: current data

Immoderate caspase-mediated apoptosis in chronic liver injury is a crucial driver of sustained HSC activation and worsening hepatic inflammation as well as fibrosis, with the ultimate outcome of liver cirrhosis and its consequences. Therefore, the inhibition of hepatocyte apoptosis by caspase cascade blockage may be a promising therapeutic strategy to achieve fibrosis regression in chronic liver diseases. Emricasan is a broad-spectrum, liver-targeted caspase inhibitor with a favorable pharmacokinetic profile, characterized by prolonged retention in the liver and low systemic exposure after oral administration. In animal models, emricasan had a clear intrahepatic anti-apoptotic effect with consequent elimination of circulating pro-inflammatory cytokines and favorable impact in liver fibrogenesis and portal pressure. Even though, this intrahepatic drug effect confirmed in human clinical trials, no clear linkage was emerged with portal hypertension, liver function or liver histology in both non-cirrhotic and cirrhotic patients except from a subgroup of patients with high MELD score (> 15) or severe HVPG (> 16 mmHg). As emricasan treatment appeared safe and well-tolerated, irrespective the severity of liver disease, more studies are required to clarify better these subgroups of patients who may benefit most from this drug.

Narrative review of current and emerging pharmacological therapies for nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) is the most common cause of chronic liver disease today, and it has now emerged as the leading etiology of end-stage liver disease requiring liver transplantation. It is a progressive form of non-alcoholic fatty liver disease which can not only progress to cirrhosis of liver and hepatocellular carcinoma (HCC), but is associated with increased cardiovascular risks too. Despite all the advances in the understanding of the risk factors and the pathogenetic pathways involved in the pathogenesis and progression of NASH, an effective therapy for NASH has not been developed yet. Although lifestyle modifications including dietary modifications and physical activity remain the mainstay of therapy, there is an unmet need to develop a drug or a combination of drugs which can not only reduce the fatty infiltration of the liver, but also arrest the development and progression of fibrosis and advancement to cirrhosis of liver and HCC. The pharmacologic therapies which are being developed target the various components believed to be involved in the pathogenesis of nonalcoholic fatty liver disease (NAFLD)/NASH which includes insulin resistance, lipid metabolism oxidative stress, lipid peroxidation, inflammatory and cell death pathways, and fibrosis. In this review, we summarize the current state of knowledge on pharmacotherapy of NASH, and also highlight the recent developments in the field, for optimizing the management and treatment of NASH.

A long way to go: caspase inhibitors in clinical use

Caspases are an evolutionary conserved family of cysteine-dependent proteases that are involved in many vital cellular processes including apoptosis, proliferation, differentiation and inflammatory response. Dysregulation of caspase-mediated apoptosis and inflammation has been linked to the pathogenesis of various diseases such as inflammatory diseases, neurological disorders, metabolic diseases, and cancer. Multiple caspase inhibitors have been designed and synthesized as a potential therapeutic tool for the treatment of cell death-related pathologies. However, only a few have progressed to clinical trials because of the consistent challenges faced amongst the different types of caspase inhibitors used for the treatment of the various pathologies, namely an inadequate efficacy, poor target specificity, or adverse side effects. Importantly, a large proportion of this failure lies in the lack of understanding various caspase functions. To overcome the current challenges, further studies on understanding caspase function in a disease model is a fundamental requirement to effectively develop their inhibitors as a treatment for the different pathologies. Therefore, the present review focuses on the descriptive properties and characteristics of caspase inhibitors known to date, and their therapeutic application in animal and clinical studies. In addition, a brief discussion on the achievements, and current challenges faced, are presented in support to providing more perspectives for further development of successful therapeutic caspase inhibitors for various diseases.

Novel Anti-inflammatory Treatments in Cirrhosis. A Literature-Based Study

Liver cirrhosis is a disease characterised by multiple complications and a poor prognosis. The prevalence is increasing worldwide. Chronic inflammation is ongoing in liver cirrhosis. No cure for the inflammation is available, and the current treatment of liver cirrhosis is only symptomatic. However, several different medical agents have been suggested as potential healing drugs. The majority are tested in rodents, but few human trials are effectuated. This review focuses on medical agents described in the literature with supposed alleviating and curing effects on liver cirrhosis. Twelve anti-inflammatory, five antioxidative, and three drugs with effects on gut microflora and the LPS pathway were found. Two drugs not categorised by the three former categories were found in addition. In total, 42 rodent studies and seven human trials were found. Promising effects of celecoxib, aspirin, curcumin, kahweol, pentoxifylline, diosmin, statins, emricasan, and silymarin were found in cirrhotic rodent models. Few indices of effects of etanercept, glycyrrhizin arginine salt, and mitoquinone were found. Faecal microbiota transplantation is in increasing searchlight with a supposed potential to alleviate cirrhosis. However, human trials are in demand to verify the findings in this review.

Clinical impact of sexual dimorphism in non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH)

NAFLD/NASH is a sex-dimorphic disease, with a general higher prevalence in men. Women are at reduced risk of NAFLD compared to men in fertile age, whereas after menopause women have a comparable prevalence of NAFLD as men. Indeed, sexual category, sex hormones and gender habits interact with numerous NAFLD factors including cytokines, stress and environmental factors and alter the risk profiles and phenotypes of NAFLD. In the present review, we summarized the last findings about the influence of sex on epidemiology, pathogenesis, progression in cirrhosis, indication for liver transplantation and alternative therapies, including lifestyle modification and pharmacological strategies. We are confident that an appropriate consideration of sex, age, hormonal status and sociocultural gender differences will lead to a better understanding of sex differences in NAFLD risk, therapeutic targets and treatment responses and will aid in achieving sex-specific personalized therapies.

Role of extracellular vesicles in liver diseases and their therapeutic potential

More than eight hundred million people worldwide have chronic liver disease, with two million deaths per year. Recurring liver injury results in fibrogenesis, progressing towards cirrhosis, for which there doesn't exists any cure except liver transplantation. Better understanding of the mechanisms leading to cirrhosis and its complications is needed to develop effective therapies. Extracellular vesicles (EVs) are released by cells and are important for cell-to-cell communication. EVs have been reported to be involved in homeostasis maintenance, as well as in liver diseases. In this review, we present current knowledge on the role of EVs in non-alcoholic fatty liver disease and non-alcoholic steatohepatitis, alcohol-associated liver disease, chronic viral hepatitis, primary liver cancers, acute liver injury and liver regeneration. Moreover, therapeutic strategies involving EVs as targets or as tools to treat liver diseases are summarized.

Portal hypertension in cirrhosis: Pathophysiological mechanisms and therapy

Portal hypertension, defined as increased pressure in the portal vein, develops as a consequence of increased intrahepatic vascular resistance due to the dysregulation of liver sinusoidal endothelial cells (LSECs) and hepatic stellate cells (HSCs), frequently arising from chronic liver diseases. Extrahepatic haemodynamic changes contribute to the aggravation of portal hypertension. The pathogenic complexity of portal hypertension and the unsuccessful translation of preclinical studies have impeded the development of effective therapeutics for patients with cirrhosis, while counteracting hepatic and extrahepatic mechanisms also pose a major obstacle to effective treatment. In this review article, we will discuss the following topics: i) cellular and molecular mechanisms of portal hypertension, focusing on dysregulation of LSECs, HSCs and hepatic microvascular thrombosis, as well as changes in the extrahepatic vasculature, since these are the major contributors to portal hypertension; ii) translational/clinical advances in our knowledge of portal hypertension; and iii) future directions.

Therapeutic pipeline in nonalcoholic steatohepatitis

Our understanding of nonalcoholic fatty liver disease pathophysiology continues to advance rapidly. Accordingly, the field has moved from describing the clinical phenotype through the presence of nonalcoholic steatohepatitis (NASH) and degree of fibrosis to deep phenotyping with a description of associated comorbidities, genetic polymorphisms and environmental influences that could be associated with disease progression. These insights have fuelled a robust therapeutic pipeline across a variety of new targets to resolve steatohepatitis or reverse fibrosis, or both. Additionally, some of these therapies have beneficial effects that extend beyond the liver, such as effects on glycaemic control, lipid profile and weight loss. In addition, emerging therapies for NASH cirrhosis would have to demonstrate either reversal of fibrosis with associated reduction in portal hypertension or at least delay the progression with eventual decrease in liver-related outcomes. For non-cirrhotic NASH, it is the expectation that reversal of fibrosis by one stage or resolution of NASH with no worsening in fibrosis will need to be accompanied by overall survival benefits. In this Review, we summarize NASH therapies that have progressed to phase II and beyond. We also discuss some of the potential clinical challenges with the use of these new therapies when approved.

Prevention of First Decompensation in Advanced Chronic Liver Disease

The first occurrence of decompensation constitutes a watershed moment in the natural history of chronic liver disease; it denotes a point of no return in a relevant proportion of patients. Preventive strategies may profoundly decrease cirrhosis-related morbidity and mortality. Removing the primary etiologic factor and cofactors, is key; however, a considerable proportion of patients require additional etiology-independent treatment strategies that target important pathomechanisms promoting decompensation (ie, portal hypertension and systemic inflammation). This article explains the importance of preventing first decompensation and summarizes the evidence for etiologic and etiology-independent (most important, nonselective beta-blockers and statins) therapies.

The Role of Hepatic Venous Pressure Gradient in the Management of Cirrhosis

Quantifying the degree of portal hypertension provides useful information to estimate prognosis and to evaluate new therapies for portal hypertension. This quantification is done in clinical practice with the measurement of the hepatic venous pressure gradient. This article addresses the applications of measuring portal pressure in cirrhosis, including the differential diagnosis of portal hypertension; estimation of prognosis in cirrhosis, including preoperative evaluation before hepatic and extrahepatic surgery; assessment of the response to drug therapy (mainly in the context of drug development); and assessing the regression of portal hypertension syndrome.

Multicenter, Double-Blind, Randomized Trial of Emricasan in Hepatitis C-Treated Liver Transplant Recipients With Residual Fibrosis or Cirrhosis

Despite achieving sustained virologic response (SVR) to hepatitis C virus (HCV) therapy, there remains a post liver transplantation population with advanced fibrosis/cirrhosis. Emricasan is an orally active, pan-caspase inhibitor that suppresses apoptosis and inflammation, potentially decreasing hepatic inflammation and fibrosis. We aimed to determine the safety and efficacy of emricasan (IDN-6556-07) in a double-blind, randomized, placebo-controlled, multicenter study in reducing or preventing the progression of hepatic fibrosis in HCV liver transplant recipients with residual fibrosis or cirrhosis after achieving SVR. A total of 64 participants were randomly assigned to receive 25 mg twice daily of emricasan or placebo in a 2:1 ratio for 24 months. 41 participants were randomly assigned to emricasan and 23 to placebo; 32 participants in the emricasan group (78.0%) and 19 who took a placebo (82.6%) completed the study. There was no difference in the primary endpoint (Ishak fibrosis stages F2-F5, improvement in fibrosis or stability; Ishak fibrosis stage F6, improvement) between the emricasan (77.1%) and placebo groups (74.1%); P = NS. There was no difference between the emricasan (54.5%) and placebo (60.7%) arms in the rate of fibrosis improvement alone. However, those in the prespecified F3 to F5 subgroup had higher rates of stability or improvement in fibrosis in the emricasan group (95.2%) compared with placebo (54.6%) (P = 0.01). The tolerability and safety profiles were similar in both groups. In conclusion, overall stability in the Ishak fibrosis stage was similar between emricasan and placebo groups at 24 months. However, there was improvement and/or stability in fibrosis stage in the prespecified F3 to F5 subgroup with emricasan versus placebo, suggesting that patients with moderate fibrosis may benefit with emricasan.

Regression of portal hypertension: underlying mechanisms and therapeutic strategies

Portal hypertension is the main non-neoplastic complication of chronic liver disease, being the cause of important life-threatening events including the development of ascites or variceal bleeding. The primary factor in the development of portal hypertension is a pathological increase in the intrahepatic vascular resistance, due to liver microcirculatory dysfunction, which is subsequently aggravated by extra-hepatic vascular disturbances including elevation of portal blood inflow. Evidence from pre-clinical models of cirrhosis has demonstrated that portal hypertension and chronic liver disease can be reversible if the injurious etiological agent is removed and can be further promoted using pharmacological therapy. These important observations have been partially demonstrated in clinical studies. This paper aims at providing an updated review of the currently available data regarding spontaneous and drug-promoted regression of portal hypertension, paying special attention to the clinical evidence. It also considers pathophysiological caveats that highlight the need for caution in establishing a new dogma that human chronic liver disease and portal hypertension is reversible.

Efficacy and safety of drugs for nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) is an inflammatory type of nonalcoholic fatty liver disease and is associated with the development and progression of cirrhosis. Lifestyle intervention is still the predominant treatment for NASH. So far, no drugs have been approved to treat NASH by the U.S. Food and Drug Administration (FDA). Vitamin E has been recommended for patients with NASH without type 2 diabetes mellitus (T2DM), whereas a combination of pioglitazone and vitamin E is recommended for patients with both NASH and T2DM. Encouragingly, drugs are currently being developed for different NASH mechanisms. Some of the drugs are at phase III clinical trials, including obeticholic acid (OCA), Elafibranor, Cenicriviroc, Selonsertib, Resmetirom, Emricasan and Aramchol. Due to its positive interim effect in attenuating the degree of hepatic fibrosis OCA was filing in FDA. However, it has been rejected by the U.S FDA and has been advised to conduct long-term studies. Therefore, in this article, we reviewed the efficacy and safety of drugs currently under clinical trials for NASH.

Strategies Targeting the Innate Immune Response for the Treatment of Hepatitis C Virus-Associated Liver Fibrosis

Direct-acting antivirals eliminate hepatitis C virus (HCV) in more than 95% of treated individuals and may abolish liver injury, arrest fibrogenesis, and reverse fibrosis and cirrhosis. However, liver regeneration is usually a slow process that is less effective in the late stages of fibrosis. What is more, fibrogenesis may prevail in patients with advanced cirrhosis, where it can progress to liver failure and hepatocellular carcinoma. Therefore, the development of antifibrotic drugs that halt and reverse fibrosis progression is urgently needed. Fibrosis occurs due to the repair process of damaged hepatic tissue, which eventually leads to scarring. The innate immune response against HCV is essential in the initiation and progression of liver fibrosis. HCV-infected hepatocytes and liver macrophages secrete proinflammatory cytokines and chemokines that promote the activation and differentiation of hepatic stellate cells (HSCs) to myofibroblasts that produce extracellular matrix (ECM) components. Prolonged ECM production by myofibroblasts due to chronic inflammation is essential to the development of fibrosis. While no antifibrotic therapy is approved to date, several drugs are being tested in phase 2 and phase 3 trials with promising results. This review discusses current state-of-the-art knowledge on treatments targeting the innate immune system to revert chronic hepatitis C-associated liver fibrosis. Agents that cause liver damage may vary (alcohol, virus infection, etc.), but fibrosis progression shows common patterns among them, including chronic inflammation and immune dysregulation, hepatocyte injury, HSC activation, and excessive ECM deposition. Therefore, mechanisms underlying these processes are promising targets for general antifibrotic therapies.

Efficacy and Safety of Emricasan in Liver Cirrhosis and/or Fibrosis

This study aimed to perform a meta-analysis to determine the efficacy and safety of emricasan. Nine databases were searched for clinical trials investigating the efficacy of emricasan treatment in patients with liver cirrhosis or fibrosis. A manual search was conducted to identify the missing trials. The quality of the included studies was assessed using the revised Cochrane risk of bias tool. Efficacy of emricasan treatment was defined as a positive change in apoptosis-related parameters from baseline to the last follow-up visit. Overall, emricasan treatment is more effective in patients with liver cirrhosis or fibrosis than placebo (standardized mean difference [SMD] [95% confidence intervals (CI)]=0.28 [0.14; 0.41]). No significant change in model for end-stage liver disease (MELD) score between the emricasan and placebo groups was noted (SMD [95% CI]=0.18 [-0.01; 0.36]; p=0.058). A 50 mg dose of emricasan had the highest efficacy rate compared to placebo (SMD [95% CI]=0.28 [0.06; 0.50]; p=0.012), followed by the 5 mg dosing regimen (SMD [95% CI]=0.28 [0.06; 0.50]; p=0.012). Treatment with emricasan resulted in significant reductions in ALT (mean difference (MD) [95% CI]=-5.89 [-10.59; -1.20]; p=0.014) and caspase3/7 levels (MD [95%CI]=-1215.93 [-1238.53; -1193.33]; p<0.001), respectively. No significant increase in the rate of overall adverse events was noted (OR [95% CI]=1.52 [0.97; 2.37]; p=0.069). Treatment with emricasan is more effective in improving liver function and apoptosis parameters compared to placebo, with a well-tolerated safety profile. However, due to the poor quality of the analyzed studies, the small number of trials and patients, and the short follow-up periods, more robust trials are still warranted.

Spontaneous Fluctuations in Liver Biochemistries in Patients with Compensated NASH Cirrhosis: Implications for Drug Hepatotoxicity Monitoring

INTRODUCTION

Patients with cirrhosis may have spontaneous fluctuations in liver enzymes, which may confound detection of drug-induced liver injury (DILI), but these fluctuations have not been described.

OBJECTIVE

We sought to quantify spontaneous liver enzyme abnormalities in patients with cirrhosis due to nonalcoholic steatohepatitis (NASH) enrolled in clinical trials.

METHODS

We examined the laboratory values of patients with compensated cirrhosis randomized to placebo in two clinical trials for NASH. Patients in one study were followed every 13 weeks up to week 57; patients in the other study were followed every 4 weeks up to week 120.

RESULTS

In total, 53 and 85 patients were randomized to placebo in the trials. Baseline alanine aminotransferase (ALT) was greater than the laboratory upper limit of normal (ULN) in 53% and 49% of participants, aspartate aminotransferase (AST) was > ULN in 49% and 59%, alkaline phosphatase was > ULN in 36% and 27%, and bilirubin was >ULN in 13% and 19%. During follow-up, ALT increased to 2× baseline in 8% and 15%, AST increased to 2× baseline in 6% and 21%, and bilirubin increased to 2× baseline in 9% and 18%. Alkaline phosphatase did not increase to 2× baseline for any patient. The maximum ALT was 3× ULN in 9% and 12%. ALT increased to 3× baseline in three patients and to 5× ULN in two patients. No patients had elevations consistent with Hy's law. The maximum ALT for patients with abnormal baseline values was higher [median 48 U/L (range 34-299) and 56 U/L (47-85)] than for those with normal baseline values [median 26.5 U/L (range 18-33) and 29 U/L (25.5-30.5)] in both studies, respectively, with p < 0.001.

CONCLUSION

Spontaneous liver enzyme abnormalities are common in patients with NASH cirrhosis in clinical trials, and these abnormalities rarely met criteria for DILI suspicion. Further work to better define these abnormalities and continued vigilance to detect DILI in this population is needed.

Pharmacological management of portal hypertension and its complications in children: lessons from adults and opportunities for the future

INTRODUCTION

Portal hypertension (PHT) and its complications in children are thought to be distinct from adult PHT in several areas, including the underlying bio-physiology of a child in which PHT develops, but also because of the pediatric-specific etiologies that drive disease progression. And yet pharmacologic approaches to PHT in children are mainly based on adult data, modified for pediatric practice. This reality has been driven by a lack of data specific to children.

AREAS COVERED

The authors discuss current therapeutic approaches to PHT in children, including management of acute gastrointestinal variceal bleed, pharmacotherapy in prophylaxis, and established and emerging therapies to combat systemic co-morbidities that result from PHT. The few areas where pediatric-specific data exist are highlighted and the many gaps in knowledge that remain unresolved are underscored.

EXPERT OPINION

Despite decades of experience, optimal management of pediatric PHT remains undefined. In large part, this can be directly linked to a lack of basic understanding related to the unique pathophysiology and natural history that defines PHT in children. As a result, meaningful research into the utility and effectiveness of pharmacotherapy in children with PHT remains in its infancy. Large, multi-center, prospective studies will be needed to begin to establish an infrastructure on which a pediatric-specific research agenda can be built.

Antihepatic Fibrosis Drugs in Clinical Trials

Liver fibrosis is not an independent disease. It refers to the abnormal proliferation of connective tissues in the liver caused by various pathogenic factors. Thus far, liver fibrosis has been considered to be associated with a set of factors, such as viral infection, alcohol abuse, non-alcoholic fatty liver disease, and autoimmune hepatitis, as well as genetic diseases. To date, clinical therapeutics for liver fibrosis still face challenges, as elimination of potential causes and conventional antifibrotic drugs cannot alleviate fibrosis in most patients. Recently, potential therapeutic targets of liver fibrosis, such as metabolism, inflammation, cell death and the extracellular matrix, have been explored through basic and clinical research. Therefore, it is extremely urgent to review the antihepatic fibrosis therapeutics for treatment of liver fibrosis in current clinical trials.

Review article: the impact of liver-directed therapies on the atherogenic risk profile in non-alcoholic steatohepatitis

BACKGROUND

Patients with non-alcoholic fatty liver disease (NAFLD), the most common cause of chronic liver disease, are at higher risk of cardiovascular disease (CVD) and associated mortality. Therefore, it is important to understand how new therapies for non-alcoholic steatohepatitis (NASH) may impact CVD risk factors in these patients.

AIMS

To summarise the effects of drug therapies on lipid and lipoprotein levels in patients with NASH and provide insight into the potential mechanisms for the observed changes.

METHODS

PubMed searches of the literature were performed and results were compiled.

RESULTS

Recent clinical trials have highlighted the safety and efficacy of drug candidates for the treatment of NASH. Several agents have shown improvements in the histological features of NASH and liver function. Pioglitazone, a drug that is currently available for type 2 diabetes and may be useful for NASH, exhibits beneficial effects on lipids. However, agents such as farnesoid X receptor agonists, which are in development for NASH, may adversely affect circulating lipids and lipoproteins.

CONCLUSIONS

NASH is a multi-system disease with a disproportionate CVD burden. Current and future drugs for NASH have had variable impact on the atherogenic risk profile. Potential co-administration of a statin may help mitigate the negative impact of some of these therapies on lipid and lipoprotein levels.

Targeting of BCL-2 Family Members during Anticancer Treatment: A Necessary Compromise between Individual Cell and Ecosystemic Responses?

The imbalance between BCL-2 homologues and pro-death counterparts frequently noted in cancer cells endows them with a cell autonomous survival advantage. To eradicate ectopic cells, inhibitors of these homologues (BH3 mimetics) were developed to trigger, during anticancer treatment, full activation of the canonical mitochondrial apoptotic pathway and related caspases. Despite efficiency in some clinical settings, these compounds do not completely fulfill their initial promise. We herein put forth that a growing body of evidence indicates that mitochondrial integrity, controlled by BCL-2 family proteins, and downstream caspases regulate other cell death modes and influence extracellular signaling by committed cells. Moreover, intercellular communications play a key role in spreading therapeutic response across cancer cell populations and in engaging an immune response. We thus advocate that BH3 mimetics administration would be more efficient in the long term if it did not induce apoptosis in all sensitive cells at the same time, but if it could instead allow (or trigger) death signal production by non-terminally committed dying cell populations. The development of such a trade-off strategy requires to unravel the effects of BH3 mimetics not only on each individual cancer cell but also on homotypic and heterotypic cell interactions in dynamic tumor ecosystems.

Dysregulation of Cell Death in Human Chronic Inflammation

Inflammation is a fundamental biological process mediating host defense and wound healing during infections and tissue injury. Perpetuated and excessive inflammation may cause autoinflammation, autoimmunity, degenerative disorders, allergies, and malignancies. Multimodal signaling by tumor necrosis factor receptor 1 (TNFR1) plays a crucial role in determining the transition between inflammation, cell survival, and programmed cell death. Targeting TNF signaling has been proven as an effective therapeutic in several immune-related disorders. Mouse studies have provided critical mechanistic insights into TNFR1 signaling and its potential role in a broad spectrum of diseases. The characterization of patients with monogenic primary immunodeficiencies (PIDs) has highlighted the importance of TNFR1 signaling in human disease. In particular, patients with PIDs have revealed paradoxical connections between immunodeficiency, chronic inflammation, and dysregulated cell death. Importantly, studies on PIDs may help to predict beneficial effects and side-effects of therapeutic targeting of TNFR1 signaling.

High l-Carnitine Ingestion Impairs Liver Function by Disordering Gut Bacteria Composition in Mice

This article studied the effects of high l-carnitine consumption on intestinal microbiota, liver function, and metabolite distribution in mice. 16S rRNA results showed that high l-carnitine supplementation could induce the accumulation of Anaerobiospirillum, Coriobacteriaceae, Akkermansia_muciniphila, and Helicobacter. High intake of l-carnitine also induced liver injury, which was proved by the increases in the serum AST and ALT activities, production of inflammatory liver cytokines (IL-1, IL-6, TNF-α, and TNF-β), lipid metabolism (TC, TG, HDL, and LDL) disorder, and decline in antioxidant ability (SOD, GSH-Px, MDA, and RAHFR). The correlation analysis results showed that Anaerobiospirillum, Akkermansia_muciniphila, and Helicobacter were strongly positively correlated with AST, IL-1, TNF-α, TNF-β, and MDA levels (r > 0.5, p < 0.01 or p < 0.05). All in all, high l-carnitine ingestion could induce a decline in the liver function by disorder in the gut bacteria composition, resulting in an increase in TMAO metabolism.

Randomized placebo-controlled trial of emricasan for non-alcoholic steatohepatitis-related cirrhosis with severe portal hypertension

BACKGROUND & AIMS

Emricasan, an oral pan-caspase inhibitor, decreased portal pressure in experimental cirrhosis and in an open-label study in patients with cirrhosis and severe portal hypertension, defined as a hepatic venous pressure gradient (HVPG) ≥12 mmHg. We aimed to confirm these results in a placebo-controlled study in patients with non-alcoholic steatohepatitis (NASH)-related cirrhosis.

METHODS

We performed a multicenter double-blinded study, randomizing 263 patients with NASH-related cirrhosis and baseline HVPG ≥12 mmHg to twice daily oral emricasan 5 mg, 25 mg, 50 mg or placebo in a 1:1:1:1 ratio for up to 48 weeks. The primary endpoint was change in HVPG (ΔHVPG) at week 24. Secondary endpoints were changes in biomarkers (aminotransferases, caspases, cytokeratins) and development of liver-related outcomes.

RESULTS

There were no significant differences in ΔHVPG for any emricasan dose vs. placebo (-0.21, -0.45, -0.58 mmHg, respectively) adjusted for baseline HVPG, compensation status, and non-selective beta-blocker use. Compensated patients (n = 201 [76%]) tended to have a greater decrease in HVPG (emricasan all vs. placebo, p = 0.06), the decrease being greater in those with higher baseline HVPG (p = 0.018), with a significant interaction between baseline HVPG (continuous, p = 0.024; dichotomous at 16 mmHg [median], p = 0.013) and treatment. Biomarkers decreased significantly with emricasan at week 24 but returned to baseline levels by week 48. New or worsening decompensating events (∼10% over median exposure of 337 days), progression in model for end-stage liver disease and Child-Pugh scores, and treatment-emergent adverse events were similar among treatment groups.

CONCLUSIONS

Despite a reduction in biomarkers indicating target engagement, emricasan was not associated with improvement in HVPG or clinical outcomes in patients with NASH-related cirrhosis and severe portal hypertension. Compensated patients with higher baseline HVPG had evidence of a small treatment effect. Emricasan treatment appeared safe and well-tolerated.

LAY SUMMARY

Cirrhosis (scarring of the liver) is the main consequence of non-alcoholic steatohepatitis (NASH). Cirrhosis leads to high pressure in the portal vein which accounts for most of the complications of cirrhosis. Reducing portal pressure is beneficial in patients with cirrhosis. We studied the possibility that emricasan, a drug that improves inflammation and scarring in the liver, would reduce portal pressure in patients with NASH-related cirrhosis and severe portal hypertension. Our results in a large, prospective, double-blind study could not demonstrate a beneficial effect of emricasan in these patients.

CLINICAL TRIAL NUMBER

Clinical Trials.gov #NCT02960204.

Novel targeted therapies for the management of liver fibrosis

Introduction: Prolonged liver injury results in tissue damage and replacement by extracellular matrix and fibrosis. Cirrhosis represents a leading cause of mortality worldwide and imposes a major financial burden on health-care systems. Fortunately, fibrogenesis has proven to be reversible if halted early, encouraging the development of novel anti-fibrotic agents that may accelerate histological restoration. Preclinical data have elucidated numerous potential therapeutic targets and many anti-fibrotic agents are currently at various stages of clinical research.Areas covered: The present review summarizes recent clinical data regarding anti-fibrotic drugs including monoclonal antibodies, targeted conjugates, and small molecule agents.Expert opinion: Although undeniable progress has been made in the development of anti-fibrotic agents in recent years, most data currently available are derived from preclinical and early clinical studies. The efficacy and safety of these agents will need to be corroborated by larger clinical trials, some of which are ongoing with results expected in the upcoming years. Combination therapy with agents targeting different pathways of fibrogenesis will also be of great interest for the future and will need to be explored in clinical trials.

Progress in promising anti-fibrotic therapies

Introduction: Liver cirrhosis is the most deleterious consequence of chronic liver diseases of different etiologies. Progression of liver diseases to cirrhosis, irrespective of etiology, involves chronic parenchymal injury, persistent activation of inflammatory response, sustained activation of fibrogenesis and wound-healing response. Despite intensive research on antifibrotic drugs, novel therapeutics specifically for liver have not been yet licensed. This review will examine compounds currently under development and key challenges in specific settings as for example that of NAFLD associated fibrosis.Areas covered: Results of the main phase II and III trial, including those with negative results, are presented and discussed. The endpoints selected and their limitations highlighted in order to suggest potential options to move forward.Expert opinion: Strategies based on single-molecule targets, associated so far with some disappointing results, may be unlikely to succeed in the context of such complex pathogenesis. Blocking at the same time different pathways that drive fibrosis progression may be required to provide significant benefit.

Pharmacological Therapy of Non-Alcoholic Fatty Liver Disease: What Drugs Are Available Now and Future Perspectives

The non-alcoholic fatty liver disease (NAFLD) is rapidly becoming the most common cause of chronic liver disease as well as the first cause of liver transplantation. NAFLD is commonly associated with metabolic syndrome (MetS), and this is the most important reason why it is extremely difficult to treat this disease bearing in mind the enormous amount of interrelationships between the liver and other systems in maintaining the metabolic health. The treatment of NAFLD is a key point to prevent NASH progression to advanced fibrosis, to prevent cirrhosis and to prevent the development of its hepatic complications (such as liver decompensation and HCC) and even extrahepatic one. A part of the well-known healthy effect of diet and physical exercise in this setting it is important to design the correct pharmaceutical strategy in order to antagonize the progression of the disease. In this regard, the current review has the scope to give a panoramic view on the possible pharmacological treatment strategy in NAFLD patients.

Pharmacologic Management of Portal Hypertension

Terlipressin, somatostatin, or octreotide are recommended as pharmacologic treatment of acute variceal hemorrhage. Nonselective β-blockers decrease the risk of variceal hemorrhage and hepatic decompensation, particularly in those 30% to 40% of patients with good hemodynamic response. Carvedilol, statins, and anticoagulants are promising agents in the management of portal hypertension. Recent advances in the pharmacologic treatment of portal hypertension have mainly focused on modifying an increased intrahepatic resistance through nitric oxide and/or modulation of vasoactive substances. Several novel pharmacologic agents for portal hypertension are being evaluated in humans.

Caspases in Cell Death, Inflammation, and Disease

Caspases are an evolutionary conserved family of cysteine proteases that are centrally involved in cell death and inflammation responses. A wealth of foundational insight into the molecular mechanisms that control caspase activation has emerged in recent years. Important advancements include the identification of additional inflammasome platforms and pathways that regulate activation of inflammatory caspases; the discovery of gasdermin D as the effector of pyroptosis and interleukin (IL)-1 and IL-18 secretion; and the existence of substantial crosstalk between inflammatory and apoptotic initiator caspases. A better understanding of the mechanisms regulating caspase activation has supported initial efforts to modulate dysfunctional cell death and inflammation pathways in a suite of communicable, inflammatory, malignant, metabolic, and neurodegenerative diseases. Here, we review current understanding of caspase biology with a prime focus on the inflammatory caspases and outline important topics for future experimentation.

Pharmacologic therapy for nonalcoholic steatohepatitis focusing on pathophysiology

The paradigm of chronic liver diseases has been shifting. Although hepatitis B and C viral infections are still the main causes of liver cirrhosis and hepatocellular carcinoma (HCC), the introduction of effective antiviral drugs may control or cure them in the near future. In contrast, the burden of nonalcoholic fatty liver disease (NAFLD) has been increasing for decades, and 25 to 30% of the general population in Korea is estimated to have NAFLD. Over 10% of NAFLD patients may have nonalcoholic steatohepatitis (NASH), a severe form of NAFLD. NASH can progress to cirrhosis and HCC. NASH is currently the second leading cause to be placed on the liver transplantation list in the United States. NAFLD is associated with obesity, type 2 diabetes, dyslipidemia, and metabolic syndrome. The pathophysiology is complex and associated with lipotoxicity, inflammatory cytokines, apoptosis, and insulin resistance. The only proven effective treatment is weight reduction by diet and exercise. However, this may not be effective for advanced fibrosis or cirrhosis. Therefore, effective drugs are urgently needed for treating these conditions. Unfortunately, no drugs have been approved for the treatment of NASH. Many pharmaceutical companies are trying to develop new drugs for the treatment of NASH. Some of them are in phase 2 or 3 clinical trials. Here, pharmacologic therapies in clinical trials, as well as the basic principles of drug therapy, will be reviewed, focusing on pathophysiology.