Aramchol in patients with nonalcoholic steatohepatitis: a randomized, double-blind, placebo-controlled phase 2b trial

Study on metabolic disorders in rat liver induced by different times after scalds

Previous studies have confirmed that burns and scalds can lead to metabolic disorders in the liver. However, the effects of severe burns at various time points on liver lipid metabolism disorders, as well as the relationship between these disorders and liver function, metabolism, and infection, have not yet been investigated.This study established a SD rat scald model, macroscopic observation of weight changes, histological staining, Western blot detection of fat browning and metabolic indicators, reverse transcription quantitative polymerase chain reaction analysis of the expression of liver new fat generation genes, determination of liver function and inflammatory indicators.The results show that steam scalding of 30 % of the back skin surface area of rats for 30, 20, and 10 s can result in severe skin scalds. Liver Oil Red O staining revealed fat deposition in the scald group, which became more pronounced with longer scald durations. The fat deposition was most evident on the fifth day post-scald and gradually returned to normal over time. This phenomenon is primarily attributed to elevated liver function indicators, including TBIL, ALT, and AST, in the scald group compared to the control group. Additionally, there was activation of peripheral blood inflammatory cells (WBC, MON, NEU,TNF-α, IL-6, and IL-10) and infiltration of inflammatory cells in the liver, along with liver cell edema. The honeycomb-like appearance of peripheral epididymal fat and the significant increase in the expression of lipolytic proteins (UCP1, ATGL, HSL, and P-HSL) were also observed, alongside abnormal expression of key genes (CES and SCD1) associated with liver neovascularization. The changes are caused by the combined effects of these factors.

Aramchol improves hepatic fibrosis in metabolic dysfunction-associated steatohepatitis: Results of multimodality assessment using both conventional and digital pathology

BACKGROUND AND AIMS

Antifibrotic trials rely on conventional pathology despite recognized limitations. We compared single-fiber digital image analysis with conventional pathology to quantify the antifibrotic effect of Aramchol, a stearoyl-CoA desaturase 1 inhibitor in development for metabolic dysfunction-associated steatohepatitis.

APPROACH AND RESULTS

Fifty-one patients with metabolic dysfunction-associated steatohepatitis enrolled in the open-label part of the ARMOR trial received Aramchol 300 mg BID and had paired pre-post treatment liver biopsies scored by consensus among 3 hepatopathologists, and separately assessed by a digital image analysis platform (PharmaNest) that generates a continuous phenotypic Fibrosis Composite Severity (Ph-FCS) score. Fibrosis improvement was defined as: ≥1 NASH Clinical Research Network (NASH-CRN) stage reduction; "improved" by ranked pair assessment; reduction in Ph-FCS ("any" for ≥0.3 absolute reduction and "substantial" for ≥25% relative reduction). Fibrosis improved in 31% of patients (NASH-CRN), 51% (ranked pair assessment), 74.5% (any Ph-FCS reduction), and 41% (substantial Ph-FCS reduction). Most patients with stable fibrosis by NASH-CRN or ranked pair assessment had a Ph-FCS reduction (a third with substantial reduction). Fibrosis improvement increased with treatment duration: 25% for <48 weeks versus 39% for ≥48 weeks by NASH-CRN; 43% versus 61% by ranked pair assessment, mean Ph-FCS reduction -0.54 (SD: 1.22) versus -1.72 (SD: 1.02); Ph-FCS reduction (any in 54% vs. 100%, substantial in 21% vs. 65%). The antifibrotic effect of Aramchol was corroborated by reductions in liver stiffness, Pro-C3, and enhanced liver fibrosis. Changes in Ph-FCS were positively correlated with changes in liver stiffness.

CONCLUSIONS

Continuous fibrosis scores generated in antifibrotic trials by digital image analysis quantify antifibrotic effects with greater sensitivity and a larger dynamic range than conventional pathology.

Insights into Clinical Trials for Drugs Targeting MASLD: Progress, Challenges, and Future Directions

The transition in terminology from fatty liver disease to metabolic dysfunction-associated steatotic liver disease (MASLD) marks a considerable evolution in diagnostic standards. This new definition focuses on liver fat accumulation in the context of overweight/obesity, type 2 diabetes, or metabolic dysfunction, without requiring the exclusion of other concurrent liver diseases. The new definition also provides clear guidelines for defining alcohol consumption in relation to the disease. MASLD is currently acknowledged as the most widespread liver disorder globally, affecting ~25% of the population. Despite the extensive array of clinical trials conducted in recent years, the number of approved treatments for metabolic dysfunction-associated fatty liver disease is very limited. In the review critically evaluates the results of clinical trials of related drugs and assesses the future directions for drug development trials. The renaming of MASLD presents new challenges and opportunities for the design of clinical trials and the selection of target populations for drug development.

Advances in research on metabolic dysfunction-associated steatotic liver disease

The global increase in obesity-related metabolic disorders has led to metabolic dysfunction-associated steatotic liver disease (MASLD) emerging as one of the most prevalent chronic liver disease worldwide. Despite growing concerns, the exact pathogenesis of MASLD remains unclear and no definitive treatments have been made available. Consequently, the need for comprehensive research on MASLD is more critical than ever. Gaining insight into the mechanisms of the disease can lay the groundwork for identifying new therapeutic targets and can facilitate the development of diagnostic tools that enable the early detection and intervention of MASLD. Research has discovered a multifactorial etiology for MASLD, suggesting that potential therapeutic strategies should be considered from a variety of perspectives. This review delves into the pathogenesis of MASLD, current diagnostic approaches, potential therapeutic targets, the status of clinical trials for emerging drugs, and the most promising treatment methods available today. With a focus on therapeutic targets, the aim is to offer fresh insights and guide for future research in the treatment of MASLD.

Adverse events of hepatic anti-fibrotic agents in phase 3 and above clinical trials: a descriptive analysis of the WHO-VigiAccess database

Introduction

Liver fibrosis is a pathological condition in response to chronic liver injuries. Currently, there is no Food and Drug Administration (FDA) approved pharmacotherapy for liver fibrosis. Advances in understanding hepatic fibrogenesis have led to the development of anti-fibrotic agents, and some of them have shown promise in phase 3 and above clinical trials. However, adverse drug reactions (ADRs) associated with emerging anti-fibrotic agents may hinder their efficacy and clinical applicability. This study assessed ADRs associated with anti-fibrotic agents as reported in the World Health Organization (WHO) VigiAccess database and compared the adverse reaction characteristics of these agents for optimizing therapeutic strategies.

Methods

A detailed search was conducted on ClinicalTrial.gov to identify phase 3 or 4 clinical trials involving hepatic anti-fibrotic agents. The ADR reports were retrieved from the WHO-VigiAccess database, with data categorized by demographic characteristics, geographic distribution, and System Organ Classes (SOCs). The most frequently reported ADRs were identified through descriptive analysis. Disproportionality analysis, measured by reporting odd ratio (ROR) and proportional reporting ratio (PRR), was performed to evaluate ADRs related to gastrointestinal disorders.

Results

Five hepatic anti-fibrotic agents (empagliflozin, liraglutide, candesartan, obeticholic acid, and resmetirom) were identified. A total of 130,567 ADR reports were analyzed, with empagliflozin, liraglutide, and candesartan showing significantly higher ADRs. The most frequently reported SOCs included gastrointestinal disorders (29.44%), general disorders (24.12%), and nervous system disorders (14.42%). Liraglutide demonstrated a higher risk of gastrointestinal ADRs (ROR: 4.629, 95% CI: 4.517-4.744; PRR: 3.566, 95% CI: 3.492-3.642) compared to the other agents. Severe ADRs were reported in empagliflozin, such as ketoacidosis and infections, while liraglutide was associated with pancreatitis and candesartan with acute kidney injury. Serious ADR rates varied, with candesartan reporting the highest proportion (7.28%).

Conclusion

While hepatic anti-fibrotic agents showed promise in addressing liver fibrosis, their ADR profiles underscore the importance of pharmacovigilance and personalized treatment approaches. Future efforts should focus on improving the pharmacovigilance system, expanding population diversity in trials, and conducting ongoing research and extensive post-marketing surveillance.

Drug Advances in NAFLD: Individual and Combination Treatment Strategies of Natural Products and Small-Synthetic-Molecule Drugs

Non-alcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease and is closely associated with metabolic diseases such as obesity, type 2 diabetes mellitus (T2DM), and metabolic syndrome. However, effective treatment strategies for NAFLD are still lacking. In recent years, progress has been made in understanding the pathogenesis of NAFLD, identifying multiple therapeutic targets and providing new directions for drug development. This review summarizes the recent advances in the treatment of NAFLD, focusing on the mechanisms of action of natural products, small-synthetic-molecule drugs, and combination therapy strategies. This review aims to provide new insights and strategies in treating NAFLD.

New Insights into AMPK, as a Potential Therapeutic Target in Metabolic Dysfunction-Associated Steatotic Liver Disease and Hepatic Fibrosis

AMP-activated protein kinase (AMPK) activators have garnered significant attention for their potential to prevent the progression of metabolic dysfunction-associated steatotic liver disease (MASLD) into liver fibrosis and to fundamentally improve liver function. The broad spectrum of pathways regulated by AMPK activators makes them promising alternatives to conventional liver replacement therapies and the limited pharmacological treatments currently available. In this study, we aim to illustrate the newly detailed multiple mechanisms of MASLD progression based on the multiple-hit hypothesis. This model posits that impaired lipid metabolism, combined with insulin resistance and metabolic imbalance, initiates inflammatory cascades, gut dysbiosis, and the accumulation of toxic metabolites, ultimately promoting fibrosis and accelerating MASLD progression to irreversible hepatocellular carcinoma (HCC). AMPK plays a multifaceted protective role against these pathological conditions by regulating several key downstream signaling pathways. It regulates biological effectors critical to metabolic and inflammatory responses, such as SIRT1, Nrf2, mTOR, and TGF-β, through complex and interrelated mechanisms. Due to these intricate connections, AMPK's role is pivotal in managing metabolic and inflammatory disorders. In this review, we demonstrate the specific roles of AMPK and its related pathways. Several agents directly activate AMPK by binding as agonists, while some others indirectly activate AMPK by modulating upstream molecules, including adiponectin, LKB1, and the AMP: ATP ratio. As AMPK activators can target each stage of MASLD progression, the development of AMPK activators offers immense potential to expand therapeutic strategies for liver diseases such as MASH, MASLD, and liver fibrosis.

Liver metabolism in human MASLD: A review of recent advancements using human tissue metabolomics

Global incidence of Metabolic dysfunction-Associated Steatotic Liver Disease (MASLD) is on the rise while treatments remain elusive. MASLD is a disease of dysregulated systemic and hepatic metabolism. Current understanding of disease pathophysiology as it relates to metabolome changes largely comes from studies on animal models and human plasma. However, human tissue data are crucial for transitioning from mechanisms to clinical therapies. The close relationship between MASLD and comorbidities like obesity, type 2 diabetes and dyslipidemia make it difficult to determine the contribution from liver disease itself. Here, we review recent metabolomics studies in liver tissue from human MASLD patients, which have predominately focused on lipid metabolism, but also include bile acid, tricarboxylic acid (TCA) cycle, and branched chain amino acid (BCAA) metabolism. Several clinical trials are underway to target various of these lipid-related pathways in MASLD. Although only the β-selective thyroid hormone receptor agonist resmetirom has so far been approved for use, many metabolism-targeting pharmaceuticals show promising results for halting disease progression, if not promoting outright reversal. Ultimately, the scarcity of human tissue data and the variability of confounding factors, like obesity, within and between cohorts are impediments to the pathophysiological understanding required for efficient development of metabolic treatments.

Targeting Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD): Available and Future Pharmaceutical Options

Metabolic dysfunction-associated steatotic liver disease (MASLD) affects an ever-increasing part of the global population, affecting millions of individuals worldwide. Despite the progress in the treatment of other liver diseases, there is a scarcity of liver-specific drugs targeting MASLD. In light of that, research has focused both on pipeline drugs targeting multiple different receptors implicated in the pathogenesis of the disease, as well as medications already approved for other indications, that might exert beneficial effects on MASLD. The fact that MASLD is associated with an increased prevalence of obesity and type 2 diabetes mellitus (T2DM) establishes a possible pathway with respect to already available pharmaceutical interventions for this group of patients, such as glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium-glucose co-transporter-2 inhibitors (SGLT2-is). Thus, the hitherto at hand, along with the upcoming members of these families, provide much-needed options for our arsenal. This review attempts to explore old and novel dimensions of the pharmaceutical treatment of MASLD in the continuous effort of the medical society to improve patient outcomes.

Diverting hepatic lipid fluxes with lifestyles revision and pharmacological interventions as a strategy to tackle steatotic liver disease (SLD) and hepatocellular carcinoma (HCC)

Steatotic liver disease (SLD) and Hepatocellular Carcinoma (HCC) are characterised by a substantial rewiring of lipid fluxes caused by systemic metabolic unbalances and/or disrupted intracellular metabolic pathways. SLD is a direct consequence of the interaction between genetic predisposition and a chronic positive energy balance affecting whole-body energy homeostasis and the function of metabolically-competent organs. In this review, we discuss how the impairment of the cross-talk between peripheral organs and the liver stalls glucose and lipid metabolism, leading to unbalances in hepatic lipid fluxes that promote hepatic fat accumulation. We also describe how prolonged metabolic stress builds up toxic lipid species in the liver, and how lipotoxicity and metabolic disturbances drive disease progression by promoting a chronic activation of wound healing, leading to fibrosis and HCC. Last, we provide a critical overview of current state of the art (pre-clinical and clinical evidence) regarding mechanisms of action and therapeutic efficacy of candidate SLD treatment options, and their potential to interfere with SLD/HCC pathophysiology by diverting lipids away from the liver therefore improving metabolic health.

The steatotic liver disease burden paradox: unravelling the key role of alcohol

The classification of steatotic liver disease (SLD) has evolved, incorporating all conditions characterized by hepatic lipid accumulation. SLD represents a continuum of disorders that are shaped by the dynamic factors of alcohol intake and cardiometabolic risk factors. This updated classification has profound implications for both the management and research of SLD, especially with the new distinct category of patients with both metabolic and alcohol-related liver disease. In this Perspective, we highlight the pivotal role of alcohol within the SLD framework. We introduce the 'SLD burden paradox': a concept illustrating the disparity in which metabolic dysfunction-associated steatotic liver disease is more prevalent, yet individuals with SLD and excessive alcohol intake (such as in metabolic and alcohol-related liver disease and in alcohol-related liver disease) account for greater global liver-related morbidity and mortality. We explore strategies to mitigate the effect of SLD on morbidity and mortality, emphasizing the importance of early detection and reducing stigma associated with alcohol intake. Our discussion extends to methods for assessing and monitoring alcohol intake together with the critical role of managing cardiometabolic risk factors in patients across the SLD spectrum. Conclusively, we advocate for a coordinated care framework that adopts a person-centric approach when managing SLD, aiming to improve outcomes and patient care.

MetALD: Does it require a different therapeutic option?

New guidelines for the definitions of steatotic liver disease have named the entity of metabolic dysfunction and alcohol-associated liver disease (MetALD) as an overlap condition of metabolic dysfunction-associated steatotic liver disease (MASLD) and alcohol-associated liver disease. There is a broad range of therapeutics in all stages of development for MASLD, but these therapeutics, in general, have not been studied in patients with significant ongoing alcohol use. In this review, we discuss the current understanding of the endogenous and exogenous risks for MASLD and MetALD. Rational strategies for therapeutic intervention in MetALD include biopsychosocial interventions, alcohol use cessation strategies, including the use of medications for alcohol use disorder, and judicious use of therapeutics for steatotic liver disease. Therapeutics with promise for MetALD include incretin-based therapies, FGF21 agonists, thyroid hormone receptor beta agonists, sodium-glucose co-transporter 2 inhibitors, and agents to modify de novo lipogenesis. Currently, glucagon-like peptide 1 receptor agonists and peroxisome proliferator-activated receptor γ agonists have the largest body of literature supporting their use in MASLD, and there is a paucity of agents in trials for alcohol-associated liver disease. From existing studies, it is not clear if unique therapeutics or a combinatorial approach are needed for MetALD. Further elucidation of the safety and benefits of MASLD-related therapies is of paramount importance for advancing therapeutics for MetALD in carefully designed inclusive clinical trials.

Current and experimental pharmacotherapy for the management of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease, with its incidence increasing in parallel with the global prevalence of obesity and type 2 diabetes mellitus. Despite our steadily increasing knowledge of its pathogenesis, there is as yet no available pharmacotherapy specifically tailored for NAFLD. To define the appropriate management, it is important to clarify the context in which the disease appears. In the case of concurrent metabolic comorbidities, NAFLD patients are treated by targeting these comorbidities, such as diabetes and obesity. Thus, GLP-1 analogs, PPAR, and SGLT2 inhibitors have recently become central to the treatment of NAFLD. In parallel, randomized trials are being conducted to explore new agents targeting known pathways involved in NAFLD progression. However, there is an imperative need to intensify the effort to design new, safe drugs with biopsy-proven efficacy. Of note, the main target of the pharmacotherapy should be directed to the regression of fibrotic NASH, as this histologic stage has been correlated with increased overall as well as liver-related morbidity and mortality. Herein we discuss the drugs currently at the forefront of NAFLD treatment.

Dawn of an era of effective treatments for MAFLD

Fatty liver disease is a commonly occurring disease resulting in hepatic and extrahepatic complications. To date, there have been few available treatments beyond conventional lifestyle modification. While lifestyle modifications resulting in weight loss >10% have shown to be beneficial for metabolic dysfunction‐associated steatohepatitis (MASH), for the majority of patients, this is difficult to achieve. The recent approval of resmetirom (a thyroid hormone receptor beta agonist) by the Food and Drug Administration following positive results for histological outcomes in a phase 3 trial has opened the door for new treatments for metabolic (dysfunction)‐associated fatty liver disease (MAFLD) and MASH. There are currently a number of phase 3 trials targeting a variety of signaling pathways involved in the pathogenesis of metabolic steatohepatitis that are also promising. This review focuses on the currently available treatments for MAFLD and MASH, ongoing phase 3 clinical trials, and unresolved controversies in clinical trials in this area.

Stearoyl-CoA desaturase-1: a potential therapeutic target for neurological disorders

Disturbances in the fatty acid lipidome are increasingly recognized as key drivers in the progression of various brain disorders. In this review article, we delve into the impact of Δ9 fatty acid desaturases, with a particular focus on stearoyl-CoA desaturase-1 (SCD1), within the setting of neuroinflammation, neurodegeneration, and brain repair. Over the past years, it was established that inhibition or deficiency of SCD1 not only suppresses neuroinflammation but also protects against neurodegeneration in conditions such as multiple sclerosis, Alzheimer's disease, and Parkinson's disease. This protective effect is achieved through different mechanisms including enhanced remyelination, reversal of synaptic and cognitive impairments, and mitigation of α-synuclein toxicity. Intriguingly, metabolic rerouting of fatty acids via SCD1 improves the pathology associated with X-linked adrenoleukodystrophy, suggesting context-dependent benign and harmful effects of SCD1 inhibition in the brain. Here, we summarize and discuss the cellular and molecular mechanisms underlying both the beneficial and detrimental effects of SCD1 in these neurological disorders. We explore commonalities and distinctions, shedding light on potential therapeutic challenges. Additionally, we touch upon future research directions that promise to deepen our understanding of SCD1 biology in brain disorders and potentially enhance the clinical utility of SCD1 inhibitors.

The gut-liver axis: emerging mechanisms and therapeutic approaches for nonalcoholic fatty liver disease and type 2 diabetes mellitus

Nonalcoholic fatty liver disease (NAFLD), more appropriately known as metabolic (dysfunction) associated fatty liver disease (MAFLD), a prevalent condition in type 2 diabetes mellitus (T2DM) patients, is a complex condition involving hepatic lipid accumulation, inflammation, and liver fibrosis. The gut-liver axis is closely linked to metabolic dysfunction, insulin resistance, inflammation, and oxidative stress that are leading to the cooccurrence of MAFLD and T2DM cardiovascular diseases (CVDs). The purpose of this review is to raise awareness about the role of the gut-liver axis in the progression of MAFLD, T2DM and CVDs with a critical analysis of available treatment options for T2DM and MAFLD and their impact on cardiovascular health. This study analysed over 100 articles on this topic, using online searches and predefined keywords, to understand and summarise published research. Numerous studies have shown a strong correlation between gut dysfunction, particularly the gut microbiota and its metabolites, and the occurrence and progression of MAFLD and type 2 diabetes mellitus (T2DM). Herein, this article also examines the impact of the gut-liver axis on MAFLD, T2DM, and related complications, focusing on the role of gut microbiota dysbiosis in insulin resistance, T2DM and obesity-related cardiovascular complications. The study suggests potential treatment targets for MAFLD linked to T2DM, focusing on cardiovascular outcomes and the molecular mechanism of the gut-liver axis, as gut microbiota dysbiosis contributes to obesity-related metabolic abnormalities.

Role of MASLD in CVD: A review of emerging treatment options

Metabolic dysfunction-associated steatotic liver disease (MASLD), represents a growing health concern due to its strong association with metabolic syndrome, obesity, and type 2 diabetes mellitus (T2DM). This condition, characterized by excessive fat accumulation in the liver not attributed to alcohol consumption, has emerged as a leading cause of chronic liver disease globally. MASLD significantly elevates the risk of major adverse cardiovascular events (MACE) through mechanisms like increased oxidative stress, insulin resistance, and chronic inflammation, all of which contribute to the development of atherosclerosis and endothelial dysfunction. Effective management of MASLD is crucial not only for liver health but also for cardiovascular disease (CVD) prevention. Lifestyle modifications, particularly weight loss achieved through dietary changes and increased physical activity, are the cornerstone of MASLD treatment. Additionally, pharmacological interventions, especially antihyperglycemic agents, play a pivotal role in treating MASLD in patients with T2DM. Novel therapeutic agents targeting various pathways of metabolic and liver dysfunction are under investigation, offering hope for more effective management strategies. This review explores the interconnectedness of MASLD and CVD, highlighting current and emerging therapeutic approaches.

MAFLD-related hepatocellular carcinoma: Exploring the potent combination of immunotherapy and molecular targeted therapy

Hepatocellular carcinoma (HCC) is a common cause of cancer-related mortality and morbidity globally, and with the prevalence of metabolic-related diseases, the incidence of metabolic dysfunction-associated fatty liver disease (MAFLD) related hepatocellular carcinoma (MAFLD-HCC) continues to rise with the limited efficacy of conventional treatments, which has created a major challenge for HCC surveillance. Immune checkpoint inhibitors (ICIs) and molecularly targeted drugs offer new hope for advanced MAFLD-HCC, but the evidence for the use of both types of therapy in this type of tumour is still insufficient. Theoretically, the combination of immunotherapy, which awakens the body's anti-tumour immunity, and targeted therapies, which directly block key molecular events driving malignant progression in HCC, is expected to produce synergistic effects. In this review, we will discuss the progress of immunotherapy and molecular targeted therapy in MAFLD-HCC and look forward to the opportunities and challenges of the combination therapy.

Hepatic stearoyl-CoA desaturase-1 deficiency induces fibrosis and hepatocellular carcinoma-related gene activation under a high carbohydrate low fat diet

Stearoyl-CoA desaturase-1 (SCD1) is a pivotal enzyme in lipogenesis, which catalyzes the synthesis of monounsaturated fatty acids (MUFA) from saturated fatty acids, whose ablation downregulates lipid synthesis, preventing steatosis and obesity. Yet deletion of SCD1 promotes hepatic inflammation and endoplasmic reticulum stress, raising the question of whether hepatic SCD1 deficiency promotes further liver damage, including fibrosis. To delineate whether SCD1 deficiency predisposes the liver to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC), we employed in vivo SCD1 deficient global and liver-specific mouse models fed a high carbohydrate low-fat diet and in vitro established AML12 mouse cells. The absence of liver SCD1 remarkably increased the saturation of liver lipid species, as indicated by lipidomic analysis, and led to hepatic fibrosis. Consistently, SCD1 deficiency promoted hepatic gene expression related to fibrosis, cirrhosis, and HCC. Deletion of SCD1 increased the circulating levels of Osteopontin, known to be increased in fibrosis, and alpha-fetoprotein, often used as an early marker and a prognostic marker for patients with HCC. De novo lipogenesis or dietary supplementation of oleate, an SCD1-generated MUFA, restored the gene expression related to fibrosis, cirrhosis, and HCC. Although SCD1 deficient mice are protected against obesity and fatty liver, our results show that MUFA deprivation results in liver injury, including fibrosis, thus providing novel insights between MUFA insufficiency and pathways leading to fibrosis, cirrhosis, and HCC under lean non-steatotic conditions.

Potential therapeutic strategies for MASH: from preclinical to clinical development

Current treatment paradigms for metabolic dysfunction-associated steatohepatitis (MASH) are based primarily on dietary restrictions and the use of existing drugs, including anti-diabetic and anti-obesity medications. Given the limited number of approved drugs specifically for MASH, recent efforts have focused on promising strategies that specifically target hepatic lipid metabolism, inflammation, fibrosis, or a combination of these processes. In this review, we examined the pathophysiology underlying the development of MASH in relation to recent advances in effective MASH therapy. Particularly, we analyzed the effects of lipogenesis inhibitors, nuclear receptor agonists, glucagon-like peptide-1 (GLP-1) receptor (GLP-1R) agonists, fibroblast growth factor mimetics, and combinatorial therapeutic approaches. We summarize these targets along with their preclinical and clinical candidates with the ultimate goal of optimizing the therapeutic prospects for MASH.

Genome-Wide Association Analysis Identifies LILRB2 Gene for Pathological Myopia

Pathological myopia (PM) is one of the leading causes of blindness, especially in Asia. To identify the genetic risk factors of PM, a two-stage genome-wide association study (GWAS) and replication analysis in East Asian populations is conducted. The analysis identified LILRB2 in 19q13.42 as a new candidate locus for PM. The increased protein expression of LILRB2/Pirb (mouse orthologous protein) in PM patients and myopia mouse models is validated. It is further revealed that the increase in LILRB2/Pirb promoted fatty acid synthesis and lipid accumulation, leading to the destruction of choroidal function and the development of PM. This study revealed the association between LILRB2 and PM, uncovering the molecular mechanism of lipid metabolism disorders leading to the pathogenesis of PM due to LILRB2 upregulation.

Review of current and new drugs for the treatment of metabolic-associated fatty liver disease

In the past 3 decades, metabolic-associated fatty liver disease (MAFLD) has emerged as a widespread liver condition, with its global prevalence on the rise. It ranks as a leading contributor to hepatocellular carcinoma (HCC) and necessitates liver transplantation. Under the multiple parallel hits model, the pathogenesis of MAFLD stems from various liver stressors, notably nutrient overload and sedentary lifestyles. While medical management for MAFLD is well-established, encompassing non-pharmaceutical and pharmaceutical interventions, determining the most effective pharmaceutical therapy has remained elusive. This review discusses diabetic medications for MAFLD treatment, emphasizing recent studies and emerging drugs while reviewing other nondiabetic agents. Emerging evidence suggests that combination therapies hold promise for resolving MAFLD and metabolic steatohepatitis (MASH) while managing side effects. Ongoing trials play a pivotal role in elucidating the effects of mono, dual, and triple receptor agonists in individuals with MASH. With the rising burden of MAFLD/MASH and its severe consequences, the need for effective treatments is more pressing than ever. This review provides a comprehensive overview of the current landscape of pharmaceutical interventions for MAFLD and MASH, shedding light on the potential of newer drugs especially diabetic medications and the importance of ongoing research in this field.

An insight into advances and challenges in the development of potential stearoyl Co-A desaturase 1 inhibitors

Stearoyl-CoA desaturase 1 (SCD1) is one of the key enzymes involved in lipid metabolism, plays a vital role in the synthesis of monounsaturated fatty acids (MUFAs) from saturated fatty acids (SFAs). Due to its promising therapeutic potential in treating metabolic disorders, cancers, and skin diseases there is an increasing interest in the development of novel inhibitors against SCD1. This review comprehensively explores the evolution of potential SCD1 inhibitors, focusing on systemic and liver-targeted inhibitors and discusses their structure-activity relationship (SAR) pattern. Among the various small molecules reported, natural products like sterculic acid have emerged as significant SCD1 inhibitors, highlighting the potential of naturally derived compounds in therapeutic development. This review also addresses the challenges in optimizing pharmacokinetic properties and reducing adverse effects, providing insights into the future directions for the development of potential novel SCD1 inhibitors with maximum therapeutic effect and minimum side effects.

Nonalcoholic Fatty Liver Disease and Cardiovascular Disease: Causation or Association

Nonalcoholic fatty liver disease (NAFLD) is a disease process that is gaining increasing recognition. The global prevalence of NAFLD is increasing in parallel with growing rates of risk factors for NAFLD such as hypertension, obesity, diabetes, and metabolic syndrome. NAFLD has been referred to as a risk factor for cardiovascular disease (CVD). As CVD is the leading cause of morbidity and mortality worldwide, there are constant efforts to describe and alleviate its risk factors. Although there is conflicting data supporting NAFLD as a causative or associative factor for CVD, NAFLD has been shown to be associated with structural, electrical, and atherosclerotic disease processes of the heart. Shared risk factors and pathophysiologic mechanisms between NAFLD and CVD warrant further explication. Pathologic mechanisms such as endothelial dysfunction, oxidative stress, insulin resistance, genetic underpinnings, and gut microbiota dysregulation have been described in both CVD and NAFLD. The mainstay of treatment for NAFLD is lifestyle intervention including physical exercise and hypocaloric intake in addition to bariatric surgery. Investigations into various therapeutic targets to alleviate hepatic steatosis and fibrosis by way of maintaining the balance between lipid synthesis and breakdown. A major obstacle preventing the success of many pharmacologic approaches has been the effects of these medications on CVD risk. The future of pharmacologic treatment of NAFLD is promising as effective medications with limited CVD harm are being investigated.

Breakthrough in the Treatment of Metabolic Associated Steatotic Liver Disease: Is it all over?

On March 14, 2024, after more than 25 years of intense research and a long series of failures, the Food and Drug Administration approved resmetirom as first drug for the treatment of non-alcoholic steatohepatitis (NASH) with fibrosis (now Metabolic-Associated Steatotic Liver Disease - MASLD). The present review covers this difficult process, finally providing a drug to complement lifestyle intervention, that has long been the sole approved therapeutic intervention. However, the availability of a drug shown to reduce disease progression in advanced stages of diseases opens a series of questions that deserve even more intense research. How to continue ongoing trials? How to generate an appropriate use of resmetirom in the community, limiting treatment according to predefined criteria and according to individual risk assessment? How to guarantee that both hepatic and non-hepatic comorbidities are appropriately targeted? How to define cost-effective strategies that might prevent the generation of unacceptable differences within the population, given the high costs of novel drugs and the extremely high numbers of candidates to treatment? Only a close surveillance of drug use in the real world, generated by insurance databases and national healthcare system registries, might provide adequate answers to these compelling questions.

Pathophysiological Relationship between Type 2 Diabetes Mellitus and Metabolic Dysfunction-Associated Steatotic Liver Disease: Novel Therapeutic Approaches

Type 2 diabetes mellitus (T2DM), often featuring hyperglycemia or insulin resistance, is a global health concern that is increasing in prevalence in the United States and worldwide. A common complication is metabolic dysfunction-associated steatotic liver disease (MASLD), the hepatic manifestation of metabolic syndrome that is also rapidly increasing in prevalence. The majority of patients with T2DM will experience MASLD, and likewise, individuals with MASLD are at an increased risk for developing T2DM. These two disorders may act synergistically, in part due to increased lipotoxicity and inflammation within the liver, among other causes. However, the pathophysiological mechanisms by which this occurs are unclear, as is how the improvement of one disorder can ameliorate the other. This review aims to discuss the pathogenic interactions between T2D and MASLD, and will highlight novel therapeutic targets and ongoing clinical trials for the treatment of these diseases.

Obesity and MASLD: Is weight loss the (only) key to treat metabolic liver disease?

Metabolic dysfunction-associated steatotic liver disease (MASLD) closely associates with obesity and type 2 diabetes. Lifestyle intervention and bariatric surgery aiming at substantial weight loss are cornerstones of MASLD treatment by improving histological outcomes and reducing risks of comorbidities. Originally developed as antihyperglycemic drugs, incretin (co-)agonists and SGLT2 inhibitors also reduce steatosis and cardiorenovascular events. Certain incretin agonists effectively improve histological features of MASLD, but not fibrosis. Of note, beneficial effects on MASLD may not necessarily require weight loss. Despite moderate weight gain, one PPARγ agonist improved adipose tissue and MASLD with certain benefit on fibrosis in post-hoc analyses. Likewise, the first THRβ-agonist was recently provisionally approved because of significant improvements of MASLD and fibrosis. We here discuss liver-related and metabolic effects induced by different MASLD treatments and their association with weight loss. Therefore, we compare results from clinical trials on drugs acting via weight loss (incretin (co)agonists, SGLT2 inhibitors) with those exerting no weight loss (pioglitazone; resmetirom). Furthermore, other drugs in development directly targeting hepatic lipid metabolism (lipogenesis inhibitors, FGF21 analogs) are addressed. Although THRβ-agonism may effectively improve hepatic outcomes, MASLD treatment concepts should consider all cardiometabolic risk factors for effective reduction of morbidity and mortality in the affected people.

A Precision Medicine Guided Approach to the Utilization of Biomarkers in MASLD

The new nomenclature of metabolic dysfunction-associated steatotic liver disease (MASLD) emphasizes a positive diagnosis based on cardiometabolic risk factors. This definition is not only less stigmatizing but also allows for subclassification and stratification, thereby addressing the heterogeneity of what was historically referred to as nonalcoholic fatty liver disease. The heterogeneity within this spectrum is influenced by several factors which include but are not limited to demographic/dietary factors, the amount of alcohol use and drinking patterns, metabolic status, gut microbiome, genetic predisposition together with epigenetic factors. The net effect of this dynamic and intricate system-level interaction is reflected in the phenotypic presentation of MASLD. Therefore, the application of precision medicine in this scenario aims at complex phenotyping with consequent individual risk prediction, development of individualized preventive strategies, and improvements in the clinical trial designs. In this review, we aim to highlight the importance of precision medicine approaches in MASLD, including the use of novel biomarkers of disease, and its subsequent utilization in future study designs.

New advances in drug development for metabolic dysfunction-associated diseases and alcohol-associated liver disease

Metabolic disorders are currently threatening public health worldwide. Discovering new targets and developing promising drugs will reduce the global metabolic-related disease burden. Metabolic disorders primarily consist of lipid and glucose metabolic disorders. Specifically, metabolic dysfunction-associated steatosis liver disease (MASLD) and alcohol-associated liver disease (ALD) are two representative lipid metabolism disorders, while diabetes mellitus is a typical glucose metabolism disorder. In this review, we aimed to summarize the new drug candidates with promising efficacy identified in clinical trials for these diseases. These drug candidates may provide alternatives for patients with metabolic disorders and advance the progress of drug discovery for the large disease burden.

Metabolic reprogramming in liver fibrosis

Chronic liver diseases, primarily metabolic dysfunction-associated steatotic liver disease (MASLD), harmful use of alcohol, or viral hepatitis, may result in liver fibrosis, cirrhosis, and cancer. Hepatic fibrogenesis is a complex process with interactions between different resident and non-resident heterogeneous liver cell populations, ultimately leading to deposition of extracellular matrix and organ failure. Shifts in cell phenotypes and functions involve pronounced transcriptional and protein synthesis changes that require metabolic adaptations in cellular substrate metabolism, including glucose and lipid metabolism, resembling changes associated with the Warburg effect in cancer cells. Cell activation and metabolic changes are regulated by metabolic stress responses, including the unfolded protein response, endoplasmic reticulum stress, autophagy, ferroptosis, and nuclear receptor signaling. These metabolic adaptations are crucial for inflammatory and fibrogenic activation of macrophages, lymphoid cells, and hepatic stellate cells. Modulation of these pathways, therefore, offers opportunities for novel therapeutic approaches to halt or even reverse liver fibrosis progression.

Emerging targets for therapy in ALD: Lessons from NASH

Alcohol-associated liver disease due to harmful alcohol use and NAFLD associated with metabolic syndrome are the 2 most common liver diseases worldwide. Control of respective risk factors is the cornerstone in the long-term management of these diseases. Furthermore, there are no effective therapies. Both diseases are characterized by metabolic derangements; thus, the focus of this review was to broaden our understanding of metabolic targets investigated in NAFLD, and how these can be applied to alcohol-associated liver disease. Conserved pathogenic pathways such as dysregulated lipid metabolism, cell death pathways including apoptosis and activation of innate immune cells, and stellate cells mediate both alcohol and NAFLDs, resulting in histological abnormalities of steatosis, inflammation, fibrosis, and cirrhosis. However, pathways such as gut microbiome changes, glucose metabolism and insulin resistance, inflammatory signaling, and microRNA abnormalities are distinct in these 2 diseases. In this review article, we describe conserved and distinct pathogenic pathways highlighting therapeutic targets that may be of potential in both diseases and those that are unique to each disease.

Efficacy of pharmacologic interventions on magnetic resonance imaging biomarkers in patients with nonalcoholic fatty liver disease: systematic review and network meta-analysis

BACKGROUND AND AIM

Several agents are under investigation for nonalcoholic fatty liver disease (NAFLD). We assessed the comparative efficacy of pharmacologic interventions for patients with NAFLD focusing on magnetic resonance imaging (MRI) biomarkers.

METHODS

We searched Medline, Embase, and CENTRAL. We included randomized controlled trials of more than 12 weeks of intervention that recruited patients with biopsy-confirmed or MRI-confirmed NAFLD and assessed the efficacy of interventions on liver fat content (LFC) and fibrosis by means of MRI. We performed random-effects frequentist network meta-analyses and assessed confidence in our estimates using the CINeMA (Confidence in Network Meta-Analysis) approach.

RESULTS

We included 47 trials (8583 patients). Versus placebo, thiazolidinediones were the most efficacious for the absolute change in LFC, followed by vitamin E, fibroblast growth factor (FGF) analogs, and glucagon-like peptide-1 receptor agonists (GLP-1 RAs) with mean differences ranging from -7.46% (95% confidence interval [-11.0, -3.9]) to -4.36% (-7.2, -1.5). No differences between drug classes were evident. Patients receiving GLP-1 RAs or glucose-dependent insulinotropic polypeptide (GIP)/GLP-1 RAs were more likely to achieve ≥30% relative reduction in LFC. Among agents, efruxifermin produced the largest reduction in LFC compared to placebo [-13.5% (-18.5, -8.5)], followed by pioglitazone, while being superior to most interventions. The effect of interventions on magnetic resonance elastography assessed fibrosis was small and insignificant. The confidence in our estimates was low to very low.

CONCLUSIONS

Several drug classes may reduce LFC in patients with NAFLD without a significant effect on fibrosis; nevertheless, trial duration was small, and confidence in the effect estimates was low.

Exploring the potential of drug repurposing for liver diseases: A comprehensive study

Drug repurposing involves the investigation of existing drugs for new indications. It offers a great opportunity to quickly identify a new drug candidate at a lower cost than novel discovery and development. Despite the importance and potential role of drug repurposing, there is no specific definition that healthcare providers and the World Health Organization credit. Unfortunately, many similar and interchangeable concepts are being used in the literature, making it difficult to collect and analyze uniform data on repurposed drugs. This research was conducted based on understanding general criteria for drug repurposing, concentrating on liver diseases. Many drugs have been investigated for their effect on liver diseases even though they were originally approved (or on their way to being approved) for other diseases. Some of the hypotheses for drug repurposing were first captured from the literature and then processed further to test the hypothesis. Recently, with the revolution in bioinformatics techniques, scientists have started to use drug libraries and computer systems that can analyze hundreds of drugs to give a short list of candidates to be analyzed pharmacologically. However, this study revealed that drug repurposing is a potential aid that may help deal with liver diseases. It provides available or under-investigated drugs that could help treat hepatitis, liver cirrhosis, Wilson disease, liver cancer, and fatty liver. However, many further studies are needed to ensure the efficacy of these drugs on a large scale.

Oligonucleotide therapies for nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) represents a severe disease subtype of nonalcoholic fatty liver disease (NAFLD) that is thought to be highly associated with systemic metabolic abnormalities. It is characterized by a series of substantial liver damage, including hepatocellular steatosis, inflammation, and fibrosis. The end stage of NASH, in some cases, may result in cirrhosis and hepatocellular carcinoma (HCC). Nowadays a large number of investigations are actively under way to test various therapeutic strategies, including emerging oligonucleotide drugs (e.g., antisense oligonucleotide, small interfering RNA, microRNA, mimic/inhibitor RNA, and small activating RNA) that have shown high potential in treating this fatal liver disease. This article systematically reviews the pathogenesis of NASH/NAFLD, the promising druggable targets proven by current studies in chemical compounds or biological drug development, and the feasibility and limitations of oligonucleotide-based therapeutic approaches under clinical or pre-clinical studies.

Emerging drugs for the treatment of hepatic fibrosis on nonalcoholic steatohepatitis

INTRODUCTION

Approved drug therapies for nonalcoholic steatohepatitis (NASH) are lacking, for which various agents are currently being tested in clinical trials. Effective drugs for liver fibrosis, the factor most associated with prognosis in NASH, are important.

AREAS COVERED

This study reviewed the treatment of NASH with a focus on the effects of existing drugs and new drugs on liver fibrosis.

EXPERT OPINION

Considering the complex pathophysiology of fibrosis in NASH, drug therapy may target multiple pathways. The method of assessing fibrosis is important when considering treatment for liver fibrosis in NASH. The Food and Drug Administration considers an important fibrosis endpoint to be histological improvement in at least one fibrosis stage while preventing worsening of fatty hepatitis. To obtain approval as a drug for NASH, efficacy needs to be demonstrated on endpoints such as liver-related events and myocardial infarction. Among the current therapeutic agents for NASH, thiazolidinedione, sodium-glucose co-transporter 2, and selective peroxisome proliferator-activated receptors α modulator have been reported to be effective against fibrosis, although further evidence is required. The effects of pan-peroxisome proliferator-activated receptors, obeticholic acid, and fibroblast growth factor-21 analogs on liver fibrosis in the development stage therapeutics for NASH are of particular interest.

Pharmacotherapeutic options for metabolic dysfunction-associated steatotic liver disease: where are we today?

INTRODUCTION

Metabolic dysfunction-associated steatotic liver disease (MASLD) is defined by hepatic steatosis and cardiometabolic risk factors like obesity, type 2 diabetes, and dyslipidemia. Persistent metabolic injury may promote inflammatory processes resulting in metabolic dysfunction-associated steatohepatitis (MASH) and liver fibrosis. Mechanistic insights helped to identify potential drug targets, thereby supporting the development of novel compounds modulating disease drivers.

AREAS COVERED

The U.S. Food and Drug Administration has recently approved the thyroid hormone receptor β-selective thyromimetic resmetirom as the first compound to treat MASH and liver fibrosis. This review provides a comprehensive overview of current and potential future pharmacotherapeutic options and their modes of action. Lessons learned from terminated clinical trials are discussed together with the first results of trials investigating novel combinational therapeutic approaches.

EXPERT OPINION

Approval of resmetirom as the first anti-MASH agent may revolutionize the therapeutic landscape. However, long-term efficacy and safety data for resmetirom are currently lacking. In addition, heterogeneity of MASLD reflects a major challenge to define effective agents. Several lead compounds demonstrated efficacy in reducing obesity and hepatic steatosis, while anti-inflammatory and antifibrotic effects of monotherapy appear less robust. Better mechanistic understanding, exploration of combination therapies, and patient stratification hold great promise for MASLD therapy.

Metabolic Dysfunction-Associated Steatotic Liver Disease: From Pathogenesis to Current Therapeutic Options

The epidemiological burden of liver steatosis associated with metabolic diseases is continuously growing worldwide and in all age classes. This condition generates possible progression of liver damage (i.e., inflammation, fibrosis, cirrhosis, hepatocellular carcinoma) but also independently increases the risk of cardio-metabolic diseases and cancer. In recent years, the terminological evolution from "nonalcoholic fatty liver disease" (NAFLD) to "metabolic dysfunction-associated fatty liver disease" (MAFLD) and, finally, "metabolic dysfunction-associated steatotic liver disease" (MASLD) has been paralleled by increased knowledge of mechanisms linking local (i.e., hepatic) and systemic pathogenic pathways. As a consequence, the need for an appropriate classification of individual phenotypes has been oriented to the investigation of innovative therapeutic tools. Besides the well-known role for lifestyle change, a number of pharmacological approaches have been explored, ranging from antidiabetic drugs to agonists acting on the gut-liver axis and at a systemic level (mainly farnesoid X receptor (FXR) agonists, PPAR agonists, thyroid hormone receptor agonists), anti-fibrotic and anti-inflammatory agents. The intrinsically complex pathophysiological history of MASLD makes the selection of a single effective treatment a major challenge, so far. In this evolving scenario, the cooperation between different stakeholders (including subjects at risk, health professionals, and pharmaceutical industries) could significantly improve the management of disease and the implementation of primary and secondary prevention measures. The high healthcare burden associated with MASLD makes the search for new, effective, and safe drugs a major pressing need, together with an accurate characterization of individual phenotypes. Recent and promising advances indicate that we may soon enter the era of precise and personalized therapy for MASLD/MASH.

New and emerging treatments for metabolic dysfunction-associated steatohepatitis

Metabolic dysfunction-associated steatohepatitis (MASH) is a leading etiology of chronic liver disease worldwide, with increasing incidence and prevalence in the setting of the obesity epidemic. MASH is also a leading indication for liver transplantation, given its associated risk of progression to end-stage liver disease. A key challenge in managing MASH is the lack of approved pharmacotherapy. In its absence, lifestyle interventions with a focus on healthy nutrition and regular physical activity have been the cornerstone of therapy. Real-world efficacy and sustainability of lifestyle interventions are low, however. Pharmacotherapy development for MASH is emerging with promising data from several agents with different mechanisms of action (MOAs) in phase 3 clinical trials. In this review, we highlight ongoing challenges and potential solutions in drug development for MASH and provide an overview of available data from emerging therapies across multiple MOAs.

Steatotic Liver Disease: Pathophysiology and Emerging Pharmacotherapies

Steatotic liver disease (SLD) displays a dynamic and complex disease phenotype. Consequently, the metabolic dysfunction-associated steatotic liver disease (MASLD)/metabolic dysfunction-associated steatohepatitis (MASH) therapeutic pipeline is expanding rapidly and in multiple directions. In parallel, noninvasive tools for diagnosing and monitoring responses to therapeutic interventions are being studied, and clinically feasible findings are being explored as primary outcomes in interventional trials. The realization that distinct subgroups exist under the umbrella of SLD should guide more precise and personalized treatment recommendations and facilitate advancements in pharmacotherapeutics. This review summarizes recent updates of pathophysiology-based nomenclature and outlines both effective pharmacotherapeutics and those in the pipeline for MASLD/MASH, detailing their mode of action and the current status of phase 2 and 3 clinical trials. Of the extensive arsenal of pharmacotherapeutics in the MASLD/MASH pipeline, several have been rejected, whereas other, mainly monotherapy options, have shown only marginal benefits and are now being tested as part of combination therapies, yet others are still in development as monotherapies. Although the Food and Drug Administration (FDA) has recently approved resmetirom, additional therapeutic approaches in development will ideally target MASH and fibrosis while improving cardiometabolic risk factors. Due to the urgent need for the development of novel therapeutic strategies and the potential availability of safety and tolerability data, repurposing existing and approved drugs is an appealing option. Finally, it is essential to highlight that SLD and, by extension, MASLD should be recognized and approached as a systemic disease affecting multiple organs, with the vigorous implementation of interdisciplinary and coordinated action plans. SIGNIFICANCE STATEMENT: Steatotic liver disease (SLD), including metabolic dysfunction-associated steatotic liver disease and metabolic dysfunction-associated steatohepatitis, is the most prevalent chronic liver condition, affecting more than one-fourth of the global population. This review aims to provide the most recent information regarding SLD pathophysiology, diagnosis, and management according to the latest advancements in the guidelines and clinical trials. Collectively, it is hoped that the information provided furthers the understanding of the current state of SLD with direct clinical implications and stimulates research initiatives.

A patient-based iPSC-derived hepatocyte model of alcohol-associated cirrhosis reveals bioenergetic insights into disease pathogenesis

Only ~20% of heavy drinkers develop alcohol cirrhosis (AC). While differences in metabolism, inflammation, signaling, microbiome signatures and genetic variations have been tied to the pathogenesis of AC, the key underlying mechanisms for this interindividual variability, remain to be fully elucidated. Induced pluripotent stem cell-derived hepatocytes (iHLCs) from patients with AC and healthy controls differ transcriptomically, bioenergetically and histologically. They include a greater number of lipid droplets (LDs) and LD-associated mitochondria compared to control cells. These pre-pathologic indicators are effectively reversed by Aramchol, an inhibitor of stearoyl-CoA desaturase. Bioenergetically, AC iHLCs have lower spare capacity, slower ATP production and their mitochondrial fuel flexibility towards fatty acids and glutamate is weakened. MARC1 and PNPLA3, genes implicated by GWAS in alcohol cirrhosis, show to correlate with lipid droplet-associated and mitochondria-mediated oxidative damage in AC iHLCs. Knockdown of PNPLA3 expression exacerbates mitochondrial deficits and leads to lipid droplets alterations. These findings suggest that differences in mitochondrial bioenergetics and lipid droplet formation are intrinsic to AC hepatocytes and can play a role in its pathogenesis.

Advances in management of metabolic dysfunction-associated steatotic liver disease: from mechanisms to therapeutics

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the leading cause of chronic liver disease that affects over 30% of the world's population. For decades, the heterogeneity of non-alcoholic fatty liver disease (NAFLD) has impeded our understanding of the disease mechanism and the development of effective medications. However, a recent change in the nomenclature from NAFLD to MASLD emphasizes the critical role of systemic metabolic dysfunction in the pathophysiology of this disease and therefore promotes the progress in the pharmaceutical treatment of MASLD. In this review, we focus on the mechanism underlying the abnormality of hepatic lipid metabolism in patients with MASLD, and summarize the latest progress in the therapeutic medications of MASLD that target metabolic disorders.

A revisit of drugs and potential therapeutic targets against non-alcoholic fatty liver disease: learning from clinical trials

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease, with a worldwide prevalence of 25%. Although numerous clinical trials have been conducted over the last few decades, an effective treatment has not been approved yet. Extensive research has accumulated a large amount of data and experience; however, the vast number of clinical trials and new therapeutic targets for NAFLD make it impossible to keep abreast of the relevant information. Therefore, a systematic analysis of the existing trials is necessary.

METHODS

Here, we reviewed clinical trials on NAFLD registered in the mandated federal database, ClinicalTrials.gov, to generate a detailed overview of the trials related to drugs and therapeutic targets for NAFLD treatment. Following screening for pertinence to therapy, a total of 440 entries were identified that included active trials as well as those that have already been completed, suspended, terminated, or withdrawn.

RESULTS

We summarize and systematically analyze the state, drug development pipeline, and discovery of treatment targets for NAFLD. We consider possible factors that may affect clinical outcomes. Furthermore, we discussed these results to explore the mechanisms responsible for clinical outcomes.

CONCLUSION

We summarised the landscape of current clinical trials and suggested the directions for future NAFLD therapy to assist internal medicine specialists in treating the whole clinical spectrum of this highly prevalent liver disease.

NAFLD and NASH: etiology, targets and emerging therapies

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) pose a significant threat to human health and cause a tremendous socioeconomic burden. Currently, the molecular mechanisms of NAFLD and NASH remain incompletely understood, and no effective pharmacotherapies have been approved. In the past five years, significant advances have been achieved in our understanding of the pathomechanisms and potential pharmacotherapies of NAFLD and NASH. Research advances include the investigation of the effects of the fibroblast growth factor 21 (FGF21) analog pegozafermin and the thyroid hormone receptor-β (THRβ) agonist resmetriom on hepatic fat content, NASH resolution and/or fibrosis regression. Future directions of NAFLD and NASH research (including combination therapy, organoids and humanized mouse models) are also discussed in this state-of-the-art review.

Two sides of the same coin: Non-alcoholic fatty liver disease and atherosclerosis

The prevalence of non-alcoholic fatty liver disease (NAFLD) and atherosclerosis remain high, which is primarily due to widespread adoption of a western diet and sedentary lifestyle. NAFLD, together with advanced forms of this disease such as non-alcoholic steatohepatitis (NASH) and cirrhosis, are closely associated with atherosclerotic-cardiovascular disease (ASCVD). In this review, we discussed the association between NAFLD and atherosclerosis and expounded on the common molecular biomarkers underpinning the pathogenesis of both NAFLD and atherosclerosis. Furthermore, we have summarized the mode of function and potential clinical utility of existing drugs in the context of these diseases.

Drug targets regulate systemic metabolism and provide new horizons to treat nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH), is the advanced stage of nonalcoholic fatty liver disease (NAFLD) with rapidly rising global prevalence. It is featured with severe hepatocyte apoptosis, inflammation and hepatic lipogenesis. The drugs directly targeting the processes of steatosis, inflammation and fibrosis are currently under clinical investigation. Nevertheless, the long-term ineffectiveness and remarkable adverse effects are well documented, and new concepts are required to tackle with the root causes of NASH progression. We critically assess the recently validated drug targets that regulate the systemic metabolism to ameliorate NASH. Thermogenesis promoted by mitochondrial uncouplers restores systemic energy expenditure. Furthermore, regulation of mitochondrial proteases and proteins that are pivotal for intracellular metabolic homeostasis normalize mitochondrial function. Secreted proteins also improve systemic metabolism, and NASH is ameliorated by agonizing receptors of secreted proteins with small molecules. We analyze the drug design, the advantages and shortcomings of these novel drug candidates. Meanwhile, the structural modification of current NASH therapeutics significantly increased their selectivity, efficacy and safety. Furthermore, the arising CRISPR-Cas9 screen strategy on liver organoids has enabled the identification of new genes that mediate lipid metabolism, which may serve as promising drug targets. In summary, this article discusses the in-depth novel mechanisms and the multidisciplinary approaches, and they provide new horizons to treat NASH.

Targeting the FGF19-FGFR4 pathway for cholestatic, metabolic, and cancerous diseases

Human fibroblast growth factor 19 (FGF19, or FGF15 in rodents) plays a central role in controlling bile acid (BA) synthesis through a negative feedback mechanism. This process involves a postprandial crosstalk between the BA-activated ileal farnesoid X receptor and the hepatic Klotho beta (KLB) coreceptor complexed with fibrobalst growth factor receptor 4 (FGFR4) kinase. Additionally, FGF19 regulates glucose, lipid, and energy metabolism by coordinating responses from functional KLB and FGFR1-3 receptor complexes on the periphery. Pharmacologically, native FGF19 or its analogs decrease elevated BA levels, fat content, and collateral tissue damage. This makes them effective in treating both cholestatic diseases such as primary biliary or sclerosing cholangitis (PBC or PSC) and metabolic abnormalities such as nonalcoholic steatohepatitis (NASH). However, chronic administration of FGF19 drives oncogenesis in mice by activating the FGFR4-dependent mitogenic or hepatic regenerative pathway, which could be a concern in humans. Agents that block FGF19 or FGFR4 signaling have shown great potency in preventing FGF19-responsive hepatocellular carcinoma (HCC) development in animal models. Recent phase 1/2 clinical trials have demonstrated promising results for several FGF19-based agents in selectively treating patients with PBC, PSC, NASH, or HCC. This review aims to provide an update on the clinical development of both analogs and antagonists targeting the FGF19-FGFR4 signaling pathway for patients with cholestatic, metabolic, and cancer diseases. We will also analyze potential safety and mechanistic concerns that should guide future research and advanced trials.

Key genes involved in nonalcoholic steatohepatitis improvement after bariatric surgery

Background

Nonalcoholic steatohepatitis (NASH) is the advanced stage of nonalcoholic fatty liver disease (NAFLD), one of the most prevalent chronic liver diseases. The effectiveness of bariatric surgery in treating NASH and preventing or even reversing liver fibrosis has been demonstrated in numerous clinical studies, but the underlying mechanisms and crucial variables remain unknown.

Methods

Using the GSE135251 dataset, we examined the gene expression levels of NASH and healthy livers. Then, the differentially expressed genes (DEGs) of patients with NASH, at baseline and one year after bariatric surgery, were identified in GSE83452. We overlapped the hub genes performed by protein-protein interaction (PPI) networks and DEGs with different expression trends in both datasets to obtain key genes. Genomic enrichment analysis (GSEA) and genomic variation analysis (GSVA) were performed to search for signaling pathways of key genes. Meanwhile, key molecules that regulate the key genes are found through the construction of the ceRNA network. NASH mice were induced by a high-fat diet (HFD) and underwent sleeve gastrectomy (SG). We then cross-linked the DEGs in clinical and animal samples using quantitative polymerase chain reaction (qPCR) and validated the key genes.

Results

Seven key genes (FASN, SCD, CD68, HMGCS1, SQLE, CXCL10, IGF1) with different expression trends in GSE135251 and GSE83452 were obtained with the top 30 hub genes selected by PPI. The expression of seven key genes in mice after SG was validated by qPCR. Combined with the qPCR results from NASH mice, the four genes FASN, SCD, HMGCS1, and CXCL10 are consistent with the biological analysis. The GSEA results showed that the 'cholesterol homeostasis' pathway was enriched in the FASN, SCD, HMGCS1, and SQLE high-expression groups. The high-expression groups of CD68 and CXCL10 were extremely enriched in inflammation-related pathways. The construction of the ceRNA network obtained microRNAs and ceRNAs that can regulate seven key genes expression.

Conclusion

In summary, this study contributes to our understanding of the mechanisms by which bariatric surgery improves NASH, and to the development of potential biomarkers for the treatment of NASH.

p63 controls metabolic activation of hepatic stellate cells and fibrosis via an HER2-ACC1 pathway

The p63 protein has pleiotropic functions and, in the liver, participates in the progression of nonalcoholic fatty liver disease (NAFLD). However, its functions in hepatic stellate cells (HSCs) have not yet been explored. TAp63 is induced in HSCs from animal models and patients with liver fibrosis and its levels positively correlate with NAFLD activity score and fibrosis stage. In mice, genetic depletion of TAp63 in HSCs reduces the diet-induced liver fibrosis. In vitro silencing of p63 blunts TGF-β1-induced HSCs activation by reducing mitochondrial respiration and glycolysis, as well as decreasing acetyl CoA carboxylase 1 (ACC1). Ectopic expression of TAp63 induces the activation of HSCs and increases the expression and activity of ACC1 by promoting the transcriptional activity of HER2. Genetic inhibition of both HER2 and ACC1 blunt TAp63-induced activation of HSCs. Thus, TAp63 induces HSC activation by stimulating the HER2-ACC1 axis and participates in the development of liver fibrosis.

Exploring the Multifaceted Landscape of MASLD: A Comprehensive Synthesis of Recent Studies, from Pathophysiology to Organoids and Beyond

Non-alcoholic fatty liver disease (NAFLD) is a widespread contributor to chronic liver disease globally. A recent consensus on renaming liver disease was established, and metabolic dysfunction-associated steatotic liver disease, MASLD, was chosen as the replacement for NAFLD. The disease's range extends from the less severe MASLD, previously known as non-alcoholic fatty liver (NAFL), to the more intense metabolic dysfunction-associated steatohepatitis (MASH), previously known as non-alcoholic steatohepatitis (NASH), characterized by inflammation and apoptosis. This research project endeavors to comprehensively synthesize the most recent studies on MASLD, encompassing a wide spectrum of topics such as pathophysiology, risk factors, dietary influences, lifestyle management, genetics, epigenetics, therapeutic approaches, and the prospective trajectory of MASLD, particularly exploring its connection with organoids.

Direct degradation and stabilization of proteins: New horizons in treatment of nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is featured with excessive hepatic lipid accumulation and its global prevalence is soaring. Nonalcoholic steatohepatitis (NASH), the severe systemic inflammatory subtype of NAFLD, is tightly associated with metabolic comorbidities, and the hepatocytes manifest severe inflammation and ballooning. Currently the therapeutic options for treating NASH are limited. Potent small molecules specifically intervene with the signaling pathways that promote pathogenesis of NASH. Nevertheless they have obvious adverse effects and show long-term ineffectiveness in clinical trials. It poses the fundamental question to efficiently and safely inhibit the pathogenic processes. Targeted protein degradation (TPD) belongs to the direct degradation strategies and is a burgeoning strategy. It utilizes the small molecules to bind to the target proteins and recruit the endogenous proteasome, lysosome and autophagosome-mediated degradation machineries. They effectively and specifically degrade the target proteins. It has exhibited promising therapeutic effects in treatment of cancer, neurodegenerative diseases and other diseases in a catalytic manner at low doses. We critically discuss the principles of multiple direct degradation strategies, especially PROTAC and ATTEC. We extensively analyze their emerging application in degradation of excessive pathogenic proteins and lipid droplets, which promote the progression of NASH. Moreover, we discuss the opposite strategy that utilizes the small molecules to recruit deubiquinases to stabilize the NASH/MASH-suppressing proteins. Their advantages, limitations, as well as the solutions to address the limitations have been analyzed. In summary, the innovative direct degradation strategies provide new insights into design of next-generation therapeutics to combat NASH with optimal safety paradigm and efficiency.