Angiotensin-receptor blockers as therapy for mild-to-moderate hypertension-associated non-alcoholic steatohepatitis

Interdisciplinary perspectives on the co-management of metabolic dysfunction-associated steatotic liver disease and coronary artery disease

Metabolic dysfunction-associated steatotic liver disease (MASLD) has emerged as a public health threat as it affects approximately 38% of the adult population worldwide, with its prevalence rising in step with that of obesity and type 2 diabetes. Beyond the implications of MASLD for liver health, it is also associated with cardiovascular and vascular dysfunction. Although the many shared risk factors and common metabolic milieu might indicate that cardiovascular disease and MASLD are discrete outcomes from common systemic pathogeneses, a growing body of evidence has identified a potential causal relationship between MASLD and coronary artery disease, which is the leading cause of morbidity and mortality in people with MASLD and all-cause mortality worldwide. This Review takes an interdisciplinary approach, drawing on hepatology, cardiology, endocrinology, and metabolic and internal medicine specialists to help to delineate the intricate interplay between MASLD and coronary artery disease. It sheds light on novel opportunities for targeted interventions and personalised management strategies.

Nonalcoholic steatohepatitis diagnosis and treatment from the perspective of patients and primary care physicians: a cross-sectional survey

BACKGROUND

The global prevalence of nonalcoholic steatohepatitis (NASH) is rising. Despite this, NASH is underdiagnosed and does not yet have approved pharmacological treatments. We sought to understand the path to diagnosis, patient interactions with healthcare professionals, treatment regimens, and disease management for patients with NASH.

METHODS

Cross-sectional online surveys of patients with a self-reported diagnosis of NASH and healthcare professionals treating patients with NASH were conducted from 10^th November 2020, to 1st January 2021. This manuscript focuses on responses from 152 patients with NASH and 101 primary care physicians (PCPs).

RESULTS

Patients (n = 152, mean age = 40, SD = 11) and healthcare professionals (n = 226) were located throughout the US. In the most common patient journey, 72% of patients had initial discussions about symptoms with a PCP but only 30% report receiving their NASH diagnosis from a PCP. Almost half of PCPs (47%) were not aware of any clinical practice guidelines for diagnosis and management of NASH. For ongoing management of NASH, PCPs most frequently prescribed lifestyle changes such as exercise (89%), lifestyle changes focused on diet (79%), and/or metformin (57%). Other healthcare professionals rarely referred patients to PCPs for treatment, but when they did, the primary reasons were patients struggling with lifestyle modifications (58%), needing to lose weight (46%), and needing treatment of comorbidities (42%).

CONCLUSIONS

PCPs may benefit from greater awareness of NASH and guidelines for its diagnosis and treatment. Given the absence of pharmacological treatments approved for NASH, PCPs can offer support in obesity management, comorbidity management, and risk stratification for liver disease progression.

An international Delphi consensus statement on metabolic dysfunction-associated fatty liver disease and risk of chronic kidney disease

BACKGROUND

With the rising global prevalence of fatty liver disease related to metabolic dysfunction, the association of this common liver condition with chronic kidney disease (CKD) has become increasingly evident. In 2020, the more inclusive term metabolic dysfunction-associated fatty liver disease (MAFLD) was proposed to replace the term non-alcoholic fatty liver disease (NAFLD). The observed association between MAFLD and CKD and our understanding that CKD can be a consequence of underlying metabolic dysfunction support the notion that individuals with MAFLD are at higher risk of having and developing CKD compared with those without MAFLD. However, to date, there is no appropriate guidance on CKD in individuals with MAFLD. Furthermore, there has been little attention paid to the link between MAFLD and CKD in the Nephrology community.

METHODS AND RESULTS

Using a Delphi-based approach, a multidisciplinary panel of 50 international experts from 26 countries reached a consensus on some of the open research questions regarding the link between MAFLD and CKD.

CONCLUSIONS

This Delphi-based consensus statement provided guidance on the epidemiology, mechanisms, management and treatment of MAFLD and CKD, as well as the relationship between the severity of MAFLD and risk of CKD, which establish a framework for the early prevention and management of these two common and interconnected diseases.

Comprehensive Review of Cardiovascular Disease Risk in Nonalcoholic Fatty Liver Disease

Nonalcoholic Fatty Liver Disease (NAFLD) is a growing global phenomenon, and its damaging effects in terms of cardiovascular disease (CVD) risk are becoming more apparent. NAFLD is estimated to affect around one quarter of the world population and is often comorbid with other metabolic disorders including diabetes mellitus, hypertension, coronary artery disease, and metabolic syndrome. In this review, we examine the current evidence describing the many ways that NAFLD itself increases CVD risk. We also discuss the emerging and complex biochemical relationship between NAFLD and its common comorbid conditions, and how they coalesce to increase CVD risk. With NAFLD's rising prevalence and deleterious effects on the cardiovascular system, a complete understanding of the disease must be undertaken, as well as effective strategies to prevent and treat its common comorbid conditions.

Pathophysiological Role of Chymase-Activated Matrix Metalloproteinase-9

Chymase present in mast cells can directly form matrix metalloproteinase (MMP)-9 from proMMP-9. Chymase-activated MMP-9 has been reportedly closely related to the pathogenesis of various diseases, and inflammation-related diseases in particular. Upregulated chymase and MMP-9 have been observed in tissues from patients and animal models of aortic aneurysm, inflammatory gastrointestinal and hepatic diseases, acute pancreatic failure, atopic dermatitis and rheumatoid arthritis. Chymase at these regions is only derived from mast cells, while MMP-9 is derived from macrophages and neutrophils in addition to mast cells. Chymase inhibitors attenuate MMP-9 formation from pro-MMP-9, and ameliorate the development and progression of these disorders, along with reduction in inflammatory cell numbers. MMP-9 activated by chymase might also be involved in angiogenesis in the tumor environment. Development of angiogenesis around several cancers is closely related to the expression of chymase and MMP-9, and postoperative survival curves have revealed that patients with a higher number of chymase positive cells have lower survival rates. In this review, we wanted to clarify the role of chymase-activated MMP-9, which might become an important therapeutic target for various inflammatory disorders.

Angiotensinogen Suppression: A New Tool to Treat Cardiovascular and Renal Disease

Multiple types of renin-angiotensin system (RAS) blockers exist, allowing interference with the system at the level of renin, angiotensin-converting enzyme, or the angiotensin II receptor. Yet, in particular, for the treatment of hypertension, the number of patients with uncontrolled hypertension continues to rise, either due to patient noncompliance or because of the significant renin rises that may, at least partially, overcome the effect of RAS blockade (RAS escape). New approaches to target the RAS are either direct antisense oligonucleotides that inhibit angiotensinogen RNA translation, or small interfering RNA (siRNA) that function via the RNA interference pathway. Since all angiotensins stem from angiotensinogen, lowering angiotensinogen has the potential to circumvent the RAS escape phenomenon. Moreover, antisense oligonucleotides and small interfering RNA require injections only every few weeks to months, which might reduce noncompliance. Of course, angiotensinogen suppression also poses a threat in situations where the RAS is acutely needed, for instance in women becoming pregnant during treatment, or in cases of emergency, when severe hypotension occurs. This review discusses all preclinical data on angiotensinogen suppression, as well as the limited clinical data that are currently available. It concludes that it is an exciting new tool to target the RAS with high specificity and a low side effect profile. Its long-term action might revolutionize pharmacotherapy, as it could overcome compliance problems. Preclinical and clinical programs are now carefully investigating its efficacy and safety profile, allowing an optimal introduction as a novel drug to treat cardiovascular and renal diseases in due time.

Angiotensin II type 1 receptor (AT1) blockade by Telmisartan attenuates hepatic steatosis in high-fat fed mice reducing Resistin, TRL4, and Myd88 expression

Background

Telmisartan is a non-peptide angiotensin II receptor antagonist which acts by ACE/AngII/AT1 axis blockade (ARB). In the last years increasing evidence of its metabolic benefits pointed out this drug as the most promising ARB for nonalcoholic fatty liver disease (NAFLD) treatment. The aim of the present study was to investigate the Telmisartan effect on treating NAFLD in mice fed with a high-fat diet evaluating liver gene modulation. Twenty-four male mice were divided into four groups and fed for 60 days with a standard diet (ST), standard diet plus TEL (ST+TEL 5 mg/kg/day by gavage for 4 weeks), high-fat diet (HFD), or high-fat diet plus TEL (HFD+TEL 5 mg/kg/day by gavage for 4 weeks). Body weight, lipid profile, insulin, alanine transaminase, and aspartate aminotransferase were evaluated. Liver histology was analyzed. US imaging was performed to access liver dimension and echogenicity and also epididymal fat pad thickness. The expression of proinflammatory resistin/TRL4/MYD88 pathway was analyzed.

Results

The main findings showed that TEL reduced the resistin, TRL4, and Myd88 liver expression in the HFD + TEL group when compared to the obese control group (HFD). Decreased hepatic steatosis in the HFD + TEL group demonstrated by US measurements of the liver longitudinal axis and echogenicity were observed. In addition, TEL reduced epididymal adipose pad thickness, body weight, transaminases, and improved glucose tolerance test and HDL cholesterol.

Conclusions

We observed that Telmisartan treatment improved metabolism, decreasing NAFLD.

Graphical Abstract

Telmisartan improves metabolic and lipid profile and liver steatosis of obese mice

Crosstalk between kidney and liver in non-alcoholic fatty liver disease: mechanisms and therapeutic approaches

Liver and kidney are vital organs that maintain homeostasis and injury to either of them triggers pathogenic pathways affecting the other. For example, non-alcoholic fatty liver disease (NAFLD) promotes the progression of chronic kidney disease (CKD), vice versa acute kidney injury (AKI) endorses the induction and progression of liver dysfunction. Progress in clinical and basic research suggest a role of excessive fructose intake, insulin resistance, inflammatory cytokines production, activation of the renin-angiotensin system, redox imbalance, and their impact on epigenetic regulation of gene expression in this context. Recent developments in experimental and clinical research have identified several biochemical and molecular pathways for AKI-liver interaction, including altered liver enzymes profile, metabolic acidosis, oxidative stress, activation of inflammatory and regulated cell death pathways. This review focuses on the current preclinical and clinical findings on kidney-liver crosstalk in NAFLD-CKD and AKI-liver dysfunction settings and highlights potential molecular mechanisms and therapeutic targets.

Trends in drug prescriptions for type 2 diabetes, hypertension, and dyslipidemia among adults with non-alcoholic fatty liver disease

INTRODUCTION AND OBJECTIVES

Clinical guidelines recommend specific drugs for type 2 diabetes (T2D), hypertension, and dyslipidemia in patients with non-alcoholic fatty liver disease (NAFLD) and/or non-alcoholic steatohepatitis (NASH). We aimed to investigate the differences in prescription trends of antidiabetic, antihypertensive, and lipid-lowering drugs among adult patients according to the presence of comorbid NAFLD and/or NASH.

METHODS

We conducted a cross-sectional analysis using a large claims database from January 2013 to December 2020.

RESULTS

Among 7,716,908 people, 47,157 patients with T2D, 180,050 with hypertension, and 191,348 with dyslipidemia were identified. A total of 8,897, 16,451, and 24,762 patients with NAFLD, as well as 435, 523, and 1033 patients with NASH, had T2D, hypertension, and dyslipidemia, respectively. Among antidiabetic drugs, sodium-glucose cotransporter-2 inhibitors (SGLT2is) and thiazolidine were more frequently prescribed to patients with NAFLD than to those without NAFLD (non-NAFLD) (thiazolidine: 1.4% and 2.8% and SGLT2is: 17.8% and 25.9% for non-NAFLD and NAFLD, respectively [2019-2020]). Among antihypertensive drugs, angiotensin II receptor antagonists exhibited a slightly higher prescription ratio in patients with NAFLD (33.6% vs. 39.0%). Regarding lipid-lowering drugs, fibrates were more frequently prescribed to patients with NAFLD (10.3% vs. 18.4%).

CONCLUSIONS

Specific drugs tended to be prescribed to patients with NAFLD. However, the differences in prescription ratios were not considerable. Further investigation is required to confirm the effects of drugs on the prognosis of patients with NAFLD or NASH.

Comprehensive Review and Updates on Holistic Approach Towards Non-Alcoholic Fatty Liver Disease Management with Cardiovascular Disease

PURPOSE OF REVIEW

The global prevalence of non-alcoholic fatty liver disease (NAFLD) presents an unmet need in treating these, often asymptomatic, individuals. In this review, we summarised NAFLD management and described recent developments in non-alcoholic steatohepatitis (NASH) therapeutics that can shape the future of NAFLD.

RECENT FINDINGS

A multi-disciplinary effort in promoting sustainable lifestyle measures is paramount, with the goal of either limiting energy surplus alone or in combination with targeting downstream pathways of inflammation and fibrosis. Several antidiabetic medications like PPAR-γ agonist and glucagon-like peptide receptor agonists have beneficial effects on the metabolic profile as well as NASH histology. Vitamin E has shown promise in specific groups of patients with the haptoglobin2 allele protein. Newer drugs have demonstrated promising results in NASH resolution and fibrosis improvement such as obeticholic acid, resmetirom, aramchol, efruxifermin, aldafermin and lanifibranor. Apart from discussing the results of late stage clinical trials and the possible challenges in managing these patients with limited approved therapies, we also discussed the specific management of comorbidities (diabetes, hypertension, hyperlipidaemia, cardiovascular diseases) in NAFLD patients. Treatment strategy needs to target improvements in liver-related outcomes and cardiometabolic profile.

Malaysian Society of Gastroenterology and Hepatology consensus statement on metabolic dysfunction-associated fatty liver disease

The Malaysian Society of Gastroenterology and Hepatology saw the need for a consensus statement on metabolic dysfunction-associated fatty liver disease (MAFLD). The consensus panel consisted of experts in the field of gastroenterology/hepatology, endocrinology, bariatric surgery, family medicine, and public health. A modified Delphi process was used to prepare the consensus statements. The panel recognized the high and increasing prevalence of the disease and the consequent anticipated increase in liver-related complications and mortality. Cardiovascular disease is the leading cause of mortality in MAFLD patients; therefore, cardiovascular disease risk assessment and management is important. A simple and clear liver assessment and referral pathway was agreed upon, so that patients with more severe MAFLD can be linked to gastroenterology/hepatology care, while patients with less severe MAFLD can remain in primary care or endocrinology, where they are best managed. Lifestyle intervention is the cornerstone in the management of MAFLD. The panel provided a consensus on the use of statin, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker, sodium-glucose cotransporter-2 inhibitor, glucagon-like peptide-1 agonist, pioglitazone, vitamin E, and metformin, as well as recommendations on bariatric surgery, screening for gastroesophageal varices and hepatocellular carcinoma, and liver transplantation in MAFLD patients. Increasing the awareness and knowledge of the various stakeholders on MAFLD and incorporating MAFLD into existing noncommunicable disease-related programs and activities are important steps to tackle the disease. These consensus statements will serve as a guide on MAFLD for clinicians and other stakeholders.

Atherosclerosis and Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a common disease defined by excess fat deposition in the liver. The course of NAFLD is not fully understood, however, some pathogenic mechanisms have been identified. Accumulation of fat in liver cells is associated with insulin resistance, central obesity, triglyceride accumulation in the liver and hepatic fatty acid metabolism dysregulation that cause steatosis. The other process leads to hepatocyte inflammation and necrosis, which leads to severe hepatic disease; non-alcoholic steatohepatitis. Many clinical studies have underlined the link between NAFLD and atherosclerosis. NAFLD may alter the balance lipid-glucose metabolism as well as increase the risk of hypertension and systemic inflammation. This results in a greater risk of vascular events. The present review considers the link between NAFLD and atherosclerosis.

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.

Noninvasive measure of treatment response in non-alcoholic steatohepatitis: Insights from EMMINENCE and meta-analysis

BACKGROUND AND AIM

Liver histology changes are the current gold standard for evaluating non-alcoholic steatohepatitis (NASH), but are limited by their invasiveness and variability for sampling and interpretation. We evaluated noninvasive biomarkers as an indication of histologic changes in NASH.

METHODS

Associations between 12-month biomarker and NASH Clinical Research Network histologic score changes in 339 patients with NASH in the EMMINENCE trial was examined with multivariable models and partial canonical correlation. A meta-analysis of 17 NASH trials including 3717 patients examined associations between these same changes and histologic response within treatment groups, and treatment effects on biomarkers and on liver histology. Biopsy measures assessed were changes in ballooning, steatosis, inflammation, and fibrosis, NASH improvement without worsening of fibrosis, and fibrosis improvement without worsening of NASH. All analytic methods suggest that a combination of aspartate aminotransferase (AST), cytokeratin-18 (CK-18 [M30 or M65]), and hemoglobin A1C (HbA1c) changes best predicts overall liver biopsy changes in response to interventions.

RESULTS

The weighted average of standardized mean changes (0.403 × AST, 0.314 × CK-18, 0.283 × HbA1c) facilitated comparisons of within-group responses and treatment effects among studies included in the meta-analysis. This composite in EMMINENCE discriminated between patients with and without NASH resolution without worsening fibrosis with area under the receiver-operator characteristic curve of 0.7880, and for fibrosis improvement without NASH worsening of 0.7553.

CONCLUSION

A composite score based on changes in AST, HbA1c, and CK-18 could serve as a surrogate for liver histologic improvement and an effective objective, noninvasive tool for comparative assessment of treatment effects of novel interventions.

Diabetic Kidney Disease, Cardiovascular Disease and Non-Alcoholic Fatty Liver Disease: A New Triumvirate?

Non-alcoholic fatty liver disease is a highly prevalent disease worldwide with a renowned relation to cardiovascular disease and chronic kidney disease. These diseases share a common pathophysiology including insulin resistance, oxidative stress, chronic inflammation, dysbiosis and genetic susceptibilities. Non-alcoholic fatty liver disease is especially prevalent and more severe in type 2 diabetes. Patients with non-alcoholic fatty liver disease should have liver fibrosis assessment in order to identify those at the highest risk of adverse outcomes so that appropriate management strategies can be implemented. Early diagnosis and treatment of non-alcoholic fatty liver disease could ameliorate the burden of cardiovascular disease and chronic kidney disease.

What proportion of people have a follow-up biopsy in randomized trials of treatments for non-alcoholic steatohepatitis?: A systematic review and meta-analysis

Background and aim

Trials of treatments for non-alcoholic steatohepatitis require endpoint assessment with liver biopsies. Previous large-scale trials have calculated their sample size expecting high retention but on average did not achieve this. We aimed to quantify the proportion of participants with a valid follow-up biopsy.

Methods

We conducted a systematic review of MEDLINE and Embase until May 2020 and included randomized clinical trials of any intervention in non-alcoholic steatohepatitis with at least 1-year follow-up. We were guided by Cochrane methods to run a meta-analysis with generalized linear mixed models with random effects.

Results

Forty-one trials (n = 6,695) were included. The proportion of participants with a valid follow-up biopsy was 82% (95%CI: 78%-86%, I² = 92%). There was no evidence of a difference by location, trial length, or by allocated treatment group. Reasons for missing follow-up biopsies were, in ranked order, related to participants (95 per 1,000 participants (95%CI: 69–129, I² = 92%), medical factors, protocol, trial conduct, and other/unclear. Biopsy-related serious adverse events occurred in 16 per 1,000 participants (95% CI: 8–33, I² = 54%). No biopsy-related deaths were reported.

Conclusions

The proportion of participants with a valid follow-up biopsy in therapeutic trials in non-alcoholic steatohepatitis is on average 82%, with around 1 in 10 participants declining a follow-up biopsy. These findings can inform adequately-powered trials.

Non-Alcoholic Fatty Liver Disease and Cardiovascular Comorbidities: Pathophysiological Links, Diagnosis, and Therapeutic Management

Non-alcoholic fatty liver disease (NAFLD) has a growing prevalence in recent years. Its association with cardiovascular disease has been intensively studied, and certain correlations have been identified. The connection between these two entities has lately aroused interest regarding therapeutic management. In order to find the best therapeutic options, a detailed understanding of the pathophysiology that links (NAFLD) to cardiovascular comorbidities is needed. This review focuses on the pathogenic mechanisms that are behind these two diseases and on the therapeutic management available at this time.

Interplay between Heart Disease and Metabolic Steatosis: A Contemporary Perspective

The liver-heart axis is a growing field of interest owing to rising evidence of complex bidirectional interplay between the two organs. Recent data suggest non-alcoholic fatty liver disease (NAFLD) has a significant, independent association with a wide spectrum of structural and functional cardiac diseases, and seems to worsen cardiovascular disease (CVD) prognosis. Conversely, the effect of cardiac disease on NAFLD is not well studied and data are mostly limited to cardiogenic liver disease. We believe it is important to further investigate the heart-liver relationship because of the tremendous global health and economic burden the two diseases pose, and the impact of such investigations on clinical decision making and management guidelines for both diseases. In this review, we summarize the current knowledge on NAFLD diagnosis, its systemic manifestations, and associations with CVD. More specifically, we review the pathophysiological mechanisms that govern the interplay between NAFLD and CVD and evaluate the relationship between different CVD treatments and NAFLD progression.

Treatments for NAFLD: State of Art

Non-alcoholic fatty liver disease (NAFLD) is to date the most common chronic liver disease in clinical practice and, consequently, a major health problem worldwide. It affects approximately 30% of adults in the general population and up to 70% of patients with type 2 diabetes (T2DM). Despite the current knowledge of the epidemiology, pathogenesis, and natural history of NAFLD, no specific pharmacological therapies are until now approved for this disease and, consequently, general strategies have been proposed to manage it. They include: (a) lifestyle change in order to promote weight loss by diet and physical activity, (b) control of the main cardiometabolic risk factors, (c) correction of all modifiable risk factors leading the development and progression of advanced forms of NAFLD, and (d) prevention of hepatic and extra-hepatic complications. In the last decade, several potential agents have been widely investigated for the treatment of NAFLD and its advanced forms—shedding some light but casting a few shadows. They include some glucose-lowering drugs (such as pioglitazone, glucagon-like peptide-1 (GLP-1) receptor agonists, sodium-glucose co-transporter-2 (SGLT-2) inhibitors), antioxidants (such as vitamin E), statins or other lipid lowering agents, bile and non-bile acid farnesoid X activated receptor (FXR) agonists, and others. This narrative review discusses in detail the different available approaches with the potential to prevent and treat NAFLD and its advanced forms.

ACE2: from protection of liver disease to propagation of COVID-19

Twenty years ago, the discovery of angiotensin-converting enzyme 2 (ACE2) was an important breakthrough dramatically enhancing our understanding of the renin-angiotensin system (RAS). The classical RAS is driven by its key enzyme ACE and is pivotal in the regulation of blood pressure and fluid homeostasis. More recently, it has been recognised that the protective RAS regulated by ACE2 counterbalances many of the deleterious effects of the classical RAS. Studies in murine models demonstrated that manipulating the protective RAS can dramatically alter many diseases including liver disease. Liver-specific overexpression of ACE2 in mice with liver fibrosis has proved to be highly effective in antagonising liver injury and fibrosis progression. Importantly, despite its highly protective role in disease pathogenesis, ACE2 is hijacked by SARS-CoV-2 as a cellular receptor to gain entry to alveolar epithelial cells, causing COVID-19, a severe respiratory disease in humans. COVID-19 is frequently life-threatening especially in elderly or people with other medical conditions. As an unprecedented number of COVID-19 patients have been affected globally, there is an urgent need to discover novel therapeutics targeting the interaction between the SARS-CoV-2 spike protein and ACE2. Understanding the role of ACE2 in physiology, pathobiology and as a cellular receptor for SARS-CoV-2 infection provides insight into potential new therapeutic strategies aiming to prevent SARS-CoV-2 infection related tissue injury. This review outlines the role of the RAS with a strong focus on ACE2-driven protective RAS in liver disease and provides therapeutic approaches to develop strategies to prevent SARS-CoV-2 infection in humans.

Chymase as a Possible Therapeutic Target for Amelioration of Non-Alcoholic Steatohepatitis

The development and progression of non-alcoholic steatohepatitis (NASH) are linked to oxidative stress, inflammation, and fibrosis of the liver. Chymase, a chymotrypsin-like enzyme produced in mast cells, has various enzymatic actions. These actions include activation of angiotensin II, matrix metalloproteinase (MMP)-9, and transforming growth factor (TGF)-β, which are associated with oxidative stress, inflammation, and fibrosis, respectively. Augmentation of chymase activity in the liver has been reported in various NASH models. Generation of hepatic angiotensin II and related oxidative stress is upregulated in NASH but attenuated by treatment with a chymase inhibitor. Additionally, increases in MMP-9 and accumulation of inflammatory cells are observed in NASH but are decreased by chymase inhibitor administration. TGF-β and collagen I upregulation in NASH is also attenuated by chymase inhibition. These results in experimental NASH models demonstrate that a chymase inhibitor can effectively ameliorate NASH via the reduction of oxidative stress, inflammation, and fibrosis. Thus, chymase may be a therapeutic target for amelioration of NASH.

Differences among patients with and without nonalcoholic fatty liver disease having elevated alanine aminotransferase levels at various stages of metabolic syndrome

Background

The prevalence of nonalcoholic fatty liver disease (NAFLD) in the non-obese population has increased and NAFLD is not always recognized in individuals with metabolic syndrome (MS). The risk of cirrhosis is higher in patients having NAFLD with elevated alanine aminotransferase (ALT) levels than in those having NAFLD with normal ALT levels.

Objective

To measure the differences in clinical factors associated with NAFLD having elevation of ALT among subjects with Non-MS, Pre-MS, and MS, and to measure differences in metabolites between MS subjects with and without NAFLD having elevation of ALT.

Methods

Among 7,054 persons undergoing health check-ups, we included 3,025 subjects who met the selection criteria. We measured differences in clinical factors for NAFLD having elevation of ALT among subjects with Non-MS, Pre-MS, and MS, and compared metabolites between subjects with and without NAFLD having elevation of ALT in 32 subjects with MS.

Results

The prevalence of NAFLD and NAFLD having elevation of ALT was significantly progressively greater in subjects with Non-MS, Pre-MS, and MS (p <0.001, respectively). In the Non-MS group, there were significant differences between subjects with and without NAFLD having elevation of ALT with respect to body mass index (BMI), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, hemoglobin A1c, uric acid, aspartate aminotransferase (AST); In the Pre-MS group, there were significant differences in BMI, hypertension, AST, and gamma-glutamyl transpeptidase (GGT); In the MS group, there were significant differences in HDL-C, impaired glucose tolerance, AST, and GGT. There were significant differences in levels of metabolites of nicotinamide, inosine, and acetyl-L-carnitine between MS subjects with and without NAFLD having elevation of ALT (all p <0.05).

Conclusions

Although NAFLD having elevation of ALT is important for development of NAFLD, differences in factors associated with NAFLD having elevation of ALT at various stages of MS should be considered. Additionally, several metabolites may play roles in the identification of risk for NAFLD in individuals with MS.

Effect of telmisartan and vitamin E on liver histopathology with non-alcoholic steatohepatitis: A randomized, open-label, noninferiority trial

Background and Aim

To compare the effect of telmisartan and vitamin E on liver histopathology of non‐alcoholic steatohepatitis (NASH) patients.

Methods

This noninferiority clinical trial was conducted for 1 year. Fatty liver patients with non‐alcoholic fatty liver disease (NAFLD) activity score (NAS) ≥ 5 (in liver biopsy) were selected. All methods were in accordance with the Declaration of Helsinki. Patients who received telmisartan and vitamin E were denoted as Group‐T and Group‐E, respectively. Forty patients >18 years old were assigned and divided into two groups (20 in each group). Histological improvements were primary outcome measures.

Results

Significant improvement in NAS score was noted in both groups (Group E [GE]: 6 ± 0.8 to 4.36 ± 1.4; P = 0.00 and Group T [GT]: 5.6 ± 0.7to 4.9 ± 1.2; P = 0.03). Fibrosis score improved from 1.6 ± 0.5 to 1.5 ± 0.5 in GE and from 1.7 ± 0.9 to 1.5 ± 0.7 in GT (P = 0.67 and 0.42, respectively). Steatosis improved in GE from 2.07 ± 0.6 to 1.14 ± 0.66 (P = 0.00) and in GT from 1.94 ± 0.57 to 1.56 ± 0.8 (P = 0.05). Lobular inflammation improved from 2.0 ± 0.4 to 1.6 ± 0.5 in GE (P = 0.02) and from 1.9 ± 0.3 to 1.8 ± 0.4 in GT (P = 0.58). Ballooning score in GE decreased from 1.9 ± 0.3 to 1.7 ± 0.5 (P = 0.03), and in GT, it reduced from 1.9 ± 0.1 to 1.5 ± 0.5 (P = 0.19). NAS improvement was similar in GE (1.6 ± 1.2) and GT (0.6 ± 1.1; P = 0.07) when controlled for weight reduction.

Conclusion

Telmisartan was similar to vitamin E in improving the histology of NASH patients.

Nonalcoholic Fatty Liver Disease and the Heart: JACC State-of-the-Art Review

Nonalcoholic fatty liver disease (NAFLD) and cardiovascular disease (CVD) are both manifestations of end-organ damage of the metabolic syndrome. Through multiple pathophysiological mechanisms, CVD and NAFLD are associated with each other. Systemic inflammation, endothelial dysfunction, hepatic insulin resistance, oxidative stress, and altered lipid metabolism are some of the mechanisms by which NAFLD increases the risk of CVD. Patients with NAFLD develop increased atherosclerosis, cardiomyopathy, and arrhythmia, which clinically result in cardiovascular morbidity and mortality. Defining the mechanisms linking these 2 diseases offers the opportunity to further develop targeted therapies. The aim of this comprehensive review is to examine the association between CVD and NAFLD and discuss the overlapping management approaches.

A Review Of Current And Upcoming Treatment Modalities In Non-Alcoholic Fatty Liver Disease And Non-Alcoholic Steatohepatitis

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the West. Non-alcoholic steatohepatitis (NASH) is the progressive form of NAFLD and can lead to cirrhosis, hepatocellular carcinoma, and is associated with increased cardiovascular risks. Multiple components and risk factors are thought to be involved in the pathogenesis of NAFLD and NASH. Optimal therapy has not yet been found, but many advances have been made with the discovery of potential therapeutic options. In this paper, we aim to provide a comprehensive review of approved, studied, and upcoming treatment options for NAFLD and NASH. Non-pharmacologic therapy (lifestyle modifications and bariatric surgery) and pharmacologic therapy are both reviewed. Pharmacologic therapy target components thought to be involved in the pathogenesis of this disease process including insulin resistance, oxidative stress, inflammation, lipid metabolism, and fibrosis are reviewed in this paper. Results of the emerging treatment targets in phase 2 and 3 clinical trials are also included.

Increased Serum Angiotensin II Is a Risk Factor of Nonalcoholic Fatty Liver Disease: A Prospective Pilot Study

Background and Aims

Nonalcoholic fatty liver disease (NAFLD) is one of the most prevalent chronic liver diseases. In this prospective study, we aim to explore the role of angiotensin II (Ang II) and NLRP3 inflammasome in NAFLD patients.

Methods

We prospectively enrolled 96 patients in our hospital from September 2014 to February 2016. Patients were divided into two groups (NAFLD group and Control group), and the serum Ang II level, IL-1β, IL-18, and lipids were analyzed. Correlation and multivariable analyses were used in order to identify the potential risk factors of NAFLD.

Results

Although the two groups share a similar demographic background, the Ang II level of NAFLD group patients was significantly higher than that of the Control group (42.18 ± 12.37 vs. 36.69 ± 13.90, p = 0.014) when abdominal ultrasound was used for grouping. This finding was confirmed when a FibroScan Cap value was selected to divide participants into the NAFLD group and Control group (41.16 ± 13.06 vs. 34.85 ± 12.64, p = 0.040). Multivariable analysis showed that Ang II level is an independent risk factor of NAFLD whether abdominal ultrasound (OR = 1.056, p = 0.037) or FibroScan Cap value (OR = 1.069, p = 0.013) was deemed as the diagnostic standard. Furthermore, stepwise regression analysis was carried out between Ang II with other parameters and we discovered that Ang II had a linear correlation with IL-1β.

Conclusion

Ang II levels of NAFLD patients significantly increased, and elevated Ang II level is an independent risk factor of NAFLD. Our preliminary results also indicate that Ang II may promote the development of NAFLD by activating NLRP3 inflammasome.

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.

Cardiovascular Risk in Fatty Liver Disease: The Liver-Heart Axis-Literature Review

According to the World Health Organization, cardiovascular disease (CVD) remains the leading cause of death worldwide, accounting for approximately 18 million deaths per year. Nevertheless, the worldwide prevalence of metabolic diseases, such as type 2 diabetes mellitus, obesity, and non-alcoholic fatty liver disease (NAFLD), also known to be common risk factors for CVD, have dramatically increased over the last decades. Chronic alcohol consumption is a major cause of chronic liver diseases (CLD) as well as being a major health care cost expenditure accounting for the spending of tremendous amounts of money annually. NAFLD has become one of the major diseases plaguing the world while standing as the most common cause of liver disease in the Western countries by representing about 75% of all CLD. Currently, the most common cause of death in NAFLD remains to be CVD. Several mechanisms have been suggested to be responsible for associating FLD with CVD through several mechanisms including low-grade systemic inflammation, oxidative stress, adipokines, endoplasmic reticulum stress, lipotoxicity and microbiota dysbiosis which may also be influenced by other factors such as genetic and epigenetic variations. Despite of all this evidence, the exact mechanisms of how FLD can causally contribute to CVD are not fully elucidated and much remains unknown. Moreover, the current literature supports the increasing evidence associating FLD with several cardiovascular (CV) adverse events including coronary artery disease, increased subclinical atherosclerosis risk, structural alterations mainly left ventricular hypertrophy, increased epicardial fat thickness, valvular calcifications including aortic valve sclerosis and mitral annular calcification and functional cardiac modifications mainly diastolic dysfunction in addition to cardiac arrhythmias such as atrial fibrillation and ventricular arrythmias and conduction defects including atrioventricular blocks and bundle branch blocks. Patients with FLD should be evaluated and managed accordingly in order to prevent further complications. Possible management methods include non-pharmacological strategies including life style modifications, pharmacological therapies as well as surgical management. This review aims to summarize the current state of knowledge regarding the pathophysiological mechanisms linking FLD with an increased CV risk, in addition to associated CV adverse events and current management modalities.

Endocrine Diseases and the Liver: An Update

The endocrine system is a complex interconnected system of organs that control corporeal processes and function. Primary endocrine organs are involved in hormonal production and secretion but rely on a bevy of signals from the hypothalamic-pituitary axis and secondary endocrine organs, such as the liver. In turn, proper hepatic function is maintained through hormonal signaling. Thus, the endocrine system and liver are codependent, and diseases affecting either organs can lead to alterations in function within their counterparts. This article explores the hepato-endocrine relationship, including the effects on endocrine diseases on the liver.

Telmisartan and/or chlorogenic acid attenuates fructose-induced non-alcoholic fatty liver disease in rats: Implications of cross-talk between angiotensin, the sphingosine kinase/sphingoine-1-phosphate pathway, and TLR4 receptors

Renin-angiotensin-aldosterone system (RAS) has been implicated in non-alcoholic fatty liver disease (NAFLD); the most common cause of chronic liver diseases. There is accumulating evidence that altered TLR4 and Sphingosine kinase 1(SphK1)/sphingosine1phosphate (S1P) signaling pathways are key players in the pathogenesis of NAFLD. Cross talk of the sphingosine signaling pathway, toll-4 (TLR4) receptors, and angiotensin II was reported in various tissues. Therefore, the aim of this study was to define the contribution of these two pathways to the hepatoprotective effects of telmisartan and/or chlorogenic acid (CGA) in NAFLD. CGA is a strong antioxidant that was previously reported to inhibit angiotensin converting enzyme. Male Wistar rats were treated with either high-fructose, with or without telmisartan, CGA, telmisartan + CGA for 8 weeks. Untreated NAFL rats showed characteristics of NAFLD, as evidenced by significant increase in the body weight, insulin resistance, and serum hepatotoxicity markers (Alanine and Aspartate transaminases) and lipids as compared to the negative control group, in addition to characteristic histopathological alterations. Treatment with either telmisartan and/or CGA improved aforementioned parameters, in addition to upregulation of antioxidant enzymes (Superoxide dismutase and Glutathione peroxidase). Effect of inhibiting RAS on both sphingosine pathway and TLR4 was evident by the suppressing effect of telmisartan and/or CGA on high fructose-induced upregulation of hepatic SPK1 and S1P, in addition to concomitant up-regulation of Sphingosine-1-Phosphate receptor (S1PR)3 protein level and increased expression of S1PR1 and TLR4. As TLR4 and SPK/S1P signaling pathways play important roles in the progression of liver inflammation, the effect on sphingosine pathway and TLR4 was associated with decreased concentrations of inflammatory markers, enzyme kB kinase (IKK), nuclear factor-kB and tumor necrosis factor-α as compared to untreated NAFL group. In conclusion, the present data strongly suggests the cross-talk between angiotensin, the Sphingosine SPK/S1P Axis and TLR4 Receptors, and their role in the pathogenesis of fructose-induced NAFLD, and the protection afforded by drugs inhibiting RAS.

An AGTR1 Variant Worsens Nonalcoholic Fatty Liver Disease and the Metabolic Syndrome

Nonalcoholic fatty liver disease and hypertension are closely related but there has been little genetic evidence to link them. In this issue, Musso et al. provide evidence that a common variant in AGTR1 (A1166C) is associated with both incident hypertension and nonalcoholic fatty liver disease, as well as nonalcoholic steatohepatitis, fibrosis, dyslipidemia, and insulin resistance. AGTR1 is strongly expressed in adipose, liver, and arteries. The mechanism of this gain-of-function variant is unclear but may include adipose or endothelial dysfunction and immune activation. Despite previous unsuccessful clinical trials of angiotensin receptor blockers in nonalcoholic steatohepatitis, individuals with the rs5186A>C variant may have greater benefit from this therapy.

High Fib4 index in patients with suspected NASH is associated with elevation of chymase-dependent angiotensin II-forming activity in circulating mononuclear leucocytes

Fatal hepatic disease is closely related to non-alcoholic fatty liver disease, especially non-alcoholic steatohepatitis (NASH). NASH is associated with cardiovascular events because it develops on the background of lifestyle-related diseases. Chymase-dependent angiotensin II-forming activity (dAIIFA) in circulating mononuclear leucocytes (CML) is a marker of local angiotensin II production and inflammation. This study investigated the association between CML chymase dAIIFA and NASH. Cardiovascular outpatients were recruited and the Fib4 index (F4I) was calculated. Patients with an F4I > 2.67 were classified into the high F4I group and these patients were strongly suspected to have NASH, while patients with an F4I < 1.30 were classified into the low F4I group. Patient background factors were compared between these groups. CML chymase dAIIFA was measured by ELISA using Nma/Dnp-modified angiotensin I. Among 499 patients, 16% were classified into the high F4I group. Compared with the low F4I group, the high F4I group had a significantly higher age, pancytopenia, more frequent diabetes mellitus, lower diastolic blood pressure, lower estimated glomerular filtration rate, higher brain natriuretic peptide, lower plasma aldosterone concentration, higher total AIIFA, higher CML chymase dAIIFA, and higher pulse wave velocity. Contrary to expectations, the body mass index, triglycerides, and low-density lipoprotein cholesterol were relatively low in the high F4I group. Many cardiovascular outpatients have a high F4I and can probably be categorized as NASH. The high F4I patients had few features of metabolic syndrome and were suspected to have elevated tissue chymase dAIIFA contributing to inflammation in the liver as well as in cardiovascular organs.

Rates of and Factors Associated With Placebo Response in Trials of Pharmacotherapies for Nonalcoholic Steatohepatitis: Systematic Review and Meta-analysis

BACKGROUND & AIMS

It is important to know the extent of the placebo effect in designing randomized controlled trials for patients with nonalcoholic steatohepatitis (NASH), to accurately calculate sample size and define treatment endpoints.

METHODS

We performed a systematic review and meta-analysis of the placebo groups from randomized controlled trials of adults with NASH that provided histologic and/or magnetic resonance image-based assessments. We identified trials through a comprehensive search of MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Scopus, from each database's inception through January 2, 2018.

RESULTS

We identified 39 randomized controlled trials, comprising 1463 patients who received placebo. Histologic assessment data (the nonalcoholic fatty liver disease activity scores, NAS) were available from 956 patients; magnetic resonance spectroscopy data were available from 295 patients and magnetic resonance proton density fat fraction measurements from 61 patients. Overall, 25% of patients given placebo had an improvement in NAS by 2 or more points (95% CI, 21%-29%) with a small amount of heterogeneity (I₂ = 27%). There were improvements by at least 1 point in steatosis scores of 33% ± 3% of patients, in hepatocyte ballooning scores of 30% ± 3% of patients, in lobular inflammation scores of 32% ± 3% of patients, and in fibrosis scores of 21% ± 3% of patients, with a moderate amount of heterogeneity among trials (I₂ range, 51%-63%). Patients given placebo had a statistically significant improvement in NAS (by 0.72 ± 0.19), with a large amount of heterogeneity (I₂ = 96%). Univariate and multivariate meta-regression showed that trials with a higher baseline NAS, those conducted in South America, and those in which patients had a decrease in body mass index, were associated with greater improvements in NAS among patients given placebo. Patients given placebo had significant reductions in intrahepatic triglyceride, measured by magnetic resonance spectroscopy (by 1.45% ± 0.54%) with moderate heterogeneity (I₂ = 40%), and in magnetic resonance proton density fat fraction (by 2.43 ± 0.89), without heterogeneity (I₂ = 0). Mean serum levels of alanine and aspartate aminotransferases decreased significantly (by 11.7 ± 3.8 U/L and 5.9 ± 2.1 U/L, respectively; P < .01 for both).

CONCLUSIONS

In a meta-analysis of randomized controlled trials of NASH, patients given placebo have significant histologic, radiologic, and biochemical responses. The placebo response should be considered in designing trials of agents for treatment of NASH.

Antifibrotics in liver disease: are we getting closer to clinical use?

The process of wound healing in response to chronic liver injury leads to the development of liver fibrosis. Regardless of etiology, the profound impact of the degree of liver fibrosis on the prognosis of chronic liver diseases has been well demonstrated. While disease-specific therapy, such as treatments for viral hepatitis, has been shown to reverse liver fibrosis and cirrhosis in both clinical trials and real-life practice, subsets of patients do not demonstrate fibrosis regression. Moreover, where disease-specific therapies are not available, the need for antifibrotics exists. Increased understanding into the pathogenesis of liver fibrosis sets the stage to focus on antifibrotic therapies attempting to: (1) Minimize liver injury and inflammation; (2) Inhibit liver fibrogenesis by enhancing or inhibiting target receptor-ligand interactions or intracellular signaling pathways; and (3) Promote fibrosis resolution. While no antifibrotic therapies are currently available, a number are now being evaluated in clinical trials, and their use is becoming closer to reality for select subsets of patients.

Non-alcoholic fatty liver disease and hypertension: coprevalent or correlated?

OBJECTIVE

To provide a comprehensive review summarizing the existing evidence on the association between nonalcoholic fatty liver disease (NAFLD) and hypertension (HT) independent of other components of metabolic syndrome.

METHODS

We searched the literature through Medline and the Cochrane Library for studies evaluating the relationship between hypertension and fatty liver disease.

RESULTS

Studies testing this association are limited, but agree that HT and fatty liver disease are inter-related independent of other components of the metabolic syndrome such as obesity and diabetes mellitus. Clinical evidence shows that NAFLD is associated with new-onset HT, whereas increased blood pressure is related to the development of fatty liver disease and the possible subsequent progression to liver fibrosis. Insulin resistance and activation of the renin-angiotensin-aldosterone system (RAAS) might provide potential pathophysiologic links between these clinical entities. Until further evidence is available, patients with HT should be meticulously evaluated and treated for fatty liver disease and vice versa. RAAS inhibitors have been tested in NAFLD, presenting a favorable profile by decreasing insulin resistance and fibrosis progression.

CONCLUSION

NAFLD and HT are associated independent of traditional cardiovascular risk factors. Insulin resistance appears to be the main linking mechanism. Although RAAS inhibitors are the most beneficial treatment option for HT in patients with NAFLD, randomized studies on the administration of these agents in HT patients with NAFDL are warranted to provide optimal treatment options in these high cardiovascular risk individuals.

Reduction of liver fibrosis by rationally designed macromolecular telmisartan prodrugs

At present there are no drugs for the treatment of chronic liver fibrosis that have been approved by the Food and Drug administration of the United States. Telmisartan, a small-molecule antihypertensive drug, displays antifibrotic activity, but its clinical use is limited because it causes systemic hypotension. Here, we report the scalable and convergent synthesis of macromolecular telmisartan prodrugs optimized for preferential release in diseased liver tissue. We optimized the release of active telmisartan in fibrotic liver to be depot-like (that is, a constant therapeutic concentration) through the molecular design of telmisartan brush-arm star polymers, and show that these lead to improved efficacy and to the avoidance of dose-limiting hypotension in both metabolically and chemically induced mouse models of hepatic fibrosis, as determined by histopathology, enzyme levels in the liver, intact-tissue protein markers, hepatocyte necrosis protection, and gene-expression analyses. In rats and dogs, the prodrugs are retained long-term in liver tissue and have a well-tolerated safety profile. Our findings support the further development of telmisartan prodrugs that enable infrequent dosing in the treatment of liver fibrosis.

Risk of cardiomyopathy and cardiac arrhythmias in patients with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a common, progressive liver disease that affects up to one-quarter of the adult population worldwide. The clinical and economic burden of NAFLD is mainly due to liver-related morbidity and mortality (nonalcoholic steatohepatitis, cirrhosis or hepatocellular carcinoma) and an increased risk of developing fatal and nonfatal cardiovascular disease, chronic kidney disease and certain types of extrahepatic cancers (for example, colorectal cancer and breast cancer). Additionally, there is now accumulating evidence that NAFLD adversely affects not only the coronary arteries (promoting accelerated coronary atherosclerosis) but also all other anatomical structures of the heart, conferring an increased risk of cardiomyopathy (mainly left ventricular diastolic dysfunction and hypertrophy, leading to the development of congestive heart failure), cardiac valvular calcification (mainly aortic-valve sclerosis), cardiac arrhythmias (mainly atrial fibrillation) and some cardiac conduction defects. This Review focuses on the association between NAFLD and non-ischaemia-related cardiac disease, discusses the putative pathophysiological mechanisms and briefly summarizes current treatment options for NAFLD that might also beneficially affect cardiac disease.

Oral vitamin-A-coupled valsartan nanomedicine: High hepatic stellate cell receptors accessibility and prolonged enterohepatic residence

So far, liver fibrosis still has no clinically-approved treatment. The loss of stored vitamin-A (V_A) in hepatic stellate cells (HSCs), the main regulators to hepatic fibrosis, can be applied as a mechanism for their targeting. Valsartan is a good candidate for this approach; it is a marketed oral-therapy with inverse- and partial-agonistic activity to the over-expressed angiotensin-II type1 receptor (AT1R) and depleted nuclear peroxisome proliferator-activated receptor-gamma (PPAR-γ), respectively, in activated HSCs. However, efficacy on AT1R and PPAR-γ necessitates high drug permeability which is lacking in valsartan. In the current study, liposomes were used as nanocarriers for valsartan to improve its permeability and hence efficacy. They were coupled to V_A and characterized for HSCs-targeting. Tracing of orally-administered fluorescently-labeled V_A-coupled liposomes in normal rats and their fluorescence intensity quantification in different organs convincingly demonstrated their intestinal entrapment. On the other hands, their administration to rats with induced fibrosis revealed preferential hepatic, and less intestinal, accumulation which lasted up to six days. This indicated their uptake by intestinal stellate cells that acted as a depot for their release over time. Confocal microscopical examination of immunofluorescently-stained HSCs in liver sections, with considerable formula accumulation, confirmed HSCs-targeting and nuclear uptake. Consequently, V_A-coupled valsartan-loaded liposomes (VLC)-therapy resulted in profound re-expression of hepatic Mas-receptor and PPAR-γ, potent reduction of fibrogenic mediators' level and nearly normal liver function tests. Therefore, VLC epitomizes a promising antifibrotic therapy with exceptional extended action and additional PPAR-γ agonistic activity.

The role of the angiotensin II type I receptor blocker telmisartan in the treatment of non-alcoholic fatty liver disease: a brief review

Non-alcoholic fatty liver disease (NAFLD) is currently considered an important component of metabolic syndrome (MetS). The spectrum of NAFLD includes conditions that range from simple hepatic steatosis to non-alcoholic steatohepatitis. NAFLD is correlated with liver-related death and is predicted to be the most frequent indication for liver transplantation by 2030. Insulin resistance is directly correlated to the central mechanisms of hepatic steatosis in NAFLD patients, which is strongly correlated to the imbalance of the renin–angiotensin system, that is involved in lipid and glucose metabolism. Among the emerging treatment approaches for NAFLD is the anti-hypertensive agent telmisartan, which has positive effects on liver, lipid, and glucose metabolism, especially through its action on the renin–angiotensin system, by blocking the ACE/AngII/AT1 axis and increasing ACE2/Ang(1–7)/Mas axis activation. However, treatment with this drug is only recommended for patients with an established indication for anti-hypertensive therapy. Thus, there is an increased need for large randomized controlled trials with the aim of elucidating the effects of telmisartan on liver disease, especially NAFLD. From this perspective, the present review aims to provide a brief examination of the pathogenesis of NAFLD/NASH and the role of telmisartan on preventing liver disorders and thus to improve the discussion on potential therapies.

Analogy between non-alcoholic steatohepatitis (NASH) and hypertension: a stepwise patient-tailored approach for NASH treatment

Non-alcoholic steatohepatitis (NASH) is a common liver disorder worldwide. Although there has been improvement in our understanding of the natural history and pathogenesis of the disease, there is still no approved therapy for NASH. NASH shares many similarities with primary hypertension, in that both are extremely common disorders that can easily lead to serious complications if left untreated. Both conditions are viewed as "silent killers", because the disease can progress over a period of time prior to the occurrence of potentially deadly outcomes. While attempts to find the "miracle pill" for NASH are unrealistic, we can make an analogy with the "stepwise combination" approach developed over the last few decades for the treatment of hypertension. In the present review, we summarize some of the similarities in the concepts that underlie NASH and hypertension. The development of a stepwise patient-tailored method for the treatment of NASH is presented.

Current and future pharmacological therapies for NAFLD/NASH

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver disease worldwide, and there is no approved pharmacotherapy. The efficacy of vitamin E and pioglitazone has been established in nonalcoholic steatohepatitis (NASH), a progressive form of NAFLD. GLP-1RA and SGLT2 inhibitors, which are currently approved for use in diabetes, have shown early efficacy in NASH, and also have beneficial cardiovascular or renal effects. Innovative NASH therapies include four main pathways. The first approach is targeting hepatic fat accumulation. Medications in this approach include modulation of peroxisome proliferator-activator receptors (e.g., pemafibrate, elafibranor), medications targeting farnesoid X receptor axis [obeticholic acid; OCA)], inhibitors of de novo lipogenesis (aramchol, ACC inhibitor), and fibroblast growth factor-21 analogues. A second target is oxidative stress, inflammation, and apoptosis. This class of drug includes apoptosis signaling kinase 1 (ASK1) inhibitor and emricasan (an irreversible caspase inhibitor). A third target is intestinal microbiomes and metabolic endotoxemia. Several agents are in ongoing trials, including IMMe124, TLR4 antagonist, and solithromycin (macrolide antibiotics). The final target is hepatic fibrosis, which is strongly associated with all-cause or liver-related mortality in NASH. Antifibrotic agents are a cysteine-cysteine motif chemokine receptor-2/5 antagonist (cenicriviroc; CVC) and galectin 3 antagonist. Among a variety of medications in development, four agents such as OCA, elafibranor, ASK1 inhibitor, and CVC are currently being evaluated in an international phase 3 trial for the treatment of NASH. Within the next few years, the availability of therapeutic options for NASH will hopefully curb the rising trend of NASH-related diseases.

Chymase Inhibitor as a Novel Therapeutic Agent for Non-alcoholic Steatohepatitis

Non-alcoholic steatohepatitis (NASH) is characterized by inflammation and fibrosis, in addition to steatosis, of the liver, but no therapeutic agents have yet been established. The mast cell protease chymase can generate angiotensin II, matrix metalloproteinase-9 and transforming growth factor-β, all of which are associated with liver inflammation or fibrosis. In animal models of NASH, augmented chymase has been observed in the liver. In histological analysis, chymase inhibitor prevented hepatic steatosis, inflammation, and fibrosis. Chymase inhibitor also attenuated the augmentation of angiotensin II, matrix metalloproteinase-9, and transforming growth factor-β observed in the liver of NASH. Oxidative stress, inflammatory markers, and collagen were attenuated by chymase inhibition. Moreover, chymase inhibitor showed a mitigating effect on established NASH, and survival rates were significantly increased by treatment with chymase inhibitor. In this review, we propose that chymase inhibitor has potential as a novel therapy for NASH.

Clinical application of angiotensin receptor blockers in patients with non-alcoholic fatty liver disease: a systematic review and meta-analysis

Objective

Non-alcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases, ranging from simple steatosis to progressive steatohepatitis and cirrhosis. Because of their anti-inflammatory and anti-fibrotic effects, angiotensin receptor blockers (ARBs) are potential therapeutic agents for NAFLD. The present systematic review assessed the effectiveness of ARBs in NAFLD management.

Results

Accounting for data overlap and exclusion criteria, randomized controlled trial -based and single-arm meta-analyses were conducted for four studies with 362 patients and eight studies with 525 patients, respectively. Although alanine aminotransferase levels were not significantly affected by ARB treatment (standardized mean difference 0.20; 95% confidence interval (CI) [−0.04, 0.44]; P = 0.10), a fixed-effect model revealed a decreasing trend in alanine transaminase levels. Low-density lipoprotein levels were reduced by ARB treatment (MD 5.21; 95% CI [3.01, 7.40]; P < 0.00001), and total cholesterol also decreased in response to ARBs (MD 2.10; 95% CI [−0.37, 4.57]; P = 0.10). However, the fibrosis score and NAFLD activity score were not significantly improved by ARB treatment (MD 0.10; 95% CI [−0.58, 0.78]; P = 0.77) (MD −0.25; 95% CI [−1.05, 0.55]; P = 0.53).

Materials and Methods

Keywords were used to identify studies in PubMed, EMBASE, CENTRAL, Web of Science and CNKI published up to July 31, 2017. Single-arm and RCT-based meta-analyses of the available data were performed using RevMan (version 5.3).

Conclusions

Although ARBs significantly decreased plasma low-density lipoprotein and total cholesterol levels, the current evidence is insufficient to support the efficacy of ARBs in managing fibrosis in NAFLD patients.