Patatin-Like Phospholipase Domain-Containing Protein 3 I148M and Liver Fat and Fibrosis Scores Predict Liver Disease Mortality in the U.S. Population

Preclinical and Clinical Pharmacokinetics of JNJ-75220795, an siRNA Therapeutic Targeting PNPLA3, for Metabolic Dysfunction-Associated Steatohepatitis

JNJ-75220795 or ARO-PNPLA3 is an investigational small interfering ribonucleic acid agent conjugated with N-acetyl-d-galactosamine that targets the PNPLA3 gene, currently being developed for metabolic dysfunction-associated steatohepatitis (MASH). This study evaluated the pharmacokinetics (PK) profile of single subcutaneous doses of JNJ-75220795 in preclinical species as well as in human subjects with homozygous or heterozygous PNPLA3 I148M mutation in two phase 1 studies-a first-in-human study in the United States and a first-in-Japanese study in Japan. Preclinical PK in rats and non-human primates (NHP) showed a rapid systemic absorption and elimination following single subcutaneous doses. JNJ-75220795 was predominantly distributed to the liver with peak liver concentrations reached at 4 h and still detectable at 672 and 336 h in rats and NHPs, respectively, with an apparent liver-to-plasma area under the curve (AUC) ratio of 2800 in rats. Consistent with the preclinical findings, clinical PK showed rapid systemic absorption and clearance in humans with median peak concentrations at 3.0-9.0 h and mean short half-life of 3.4-6.2 h. Plasma PK exposure parameters including Cmax and AUC increased approximately dose proportionally. Kidney had the second highest tissue exposure following the liver in rats. Renal excretion was a significant but minor elimination pathway as approximately 15%-25% of the administered dose was recovered in urine. Based on the overall data, JNJ-75220795 was primarily localized to the liver and exhibited sustained hepatic exposures, which confer prolonged pharmacodynamic effects in the target organ. The favorable PK profiles of single subcutaneous doses observed in the phase 1 studies support continued clinical development of JNJ-75220795 for the treatment of MASH.

Targeting PNPLA3 to Treat MASH and MASH Related Fibrosis and Cirrhosis

Metabolic dysfunction-associated steatotic liver disease (MASLD) is caused by metabolic triggers and genetic predisposition. Among the genetic MASLD risk variants identified today, the common PNPLA3 148M variant exerts the largest effect size of MASLD heritability. The PNPLA3 148M protein is causatively linked to the development of liver steatosis, inflammation and fibrosis in experimental studies and is therefore an appealing target for therapeutic approaches to treat this disease. Several PNPLA3 targeted approaches are currently being evaluated in clinical trials for the treatment of metabolic dysfunction-associated steatohepatitis (MASH), the most severe form of MASLD and promising proof of principle data with reduced liver fat content in homozygous PNPLA3 148M risk allele carriers has been reported from phase 1 trials following hepatic silencing of PNPLA3. Thus, targeting PNPLA3, the strongest genetic determinant of MASH may hold promise as the first precision medicine for the treatment of this disease. A histological endpoint-based phase 2b study has been initiated and several more are expected to be initiated to evaluate treatment effects on histological MASH and liver fibrosis in participants being homozygous for the PNPLA3 148M risk allele variant. The scope of this mini-review is to briefly describe the PNPLA3 148M genetics, function and preclinical experimental evidence with therapeutic approaches targeting PNPLA3 as well as to summarise the PNPLA3 based therapies currently in clinical development.

PNPLA3 rs738409, environmental factors and liver-related mortality in the US population

BACKGROUND & AIMS

Little is known about the interplay between patatin-like phospholipase domain-containing protein 3 (PNPLA3 rs738409 C>G), environmental factors, and the risk of liver-related death.

METHODS

A total of 4,361 adults were selected from NHANES III, 1991-1994. All participants were linked to the National Death Index until 2019 (mean follow-up: 23.2 years). Liver-related death was the study outcome. Associations of PNPLA3, diet, light alcohol intake, smoking, and BMI (kg/m2) with liver-related death were examined using competing risk regression models.

RESULTS

The PNPLA3 G-allele was significantly associated with liver-related death (adjusted subhazard ratio [adj.sHR] 2.9, 95% CI 1.4-5.8). Light alcohol intake (adj.sHR 2.2, 95% CI 1.1-4.5), top quartiles of monounsaturated fat (adj.sHR 0.43, 95% CI 0.12-0.99) and cholesterol (adj.sHR 2.6, 95% CI 1.00-8.8), coffee intake ≥3 cups/day (adj.sHR 0.05, 95% CI 0.06-0.10), former/current smoking (adj.sHR 1.8, 95% CI 1.2-2.6), BMI (adj.sHR 1.1, 95% CI 1.03-1.2), and healthy eating index (adj.sHR 0.96, 95% CI 0.93-0.98) were associated with liver-related death. Joint effects between PNPLA3 and environmental factors showed that the risk of liver-related death was significantly increased in carriers of the G-allele with light alcohol intake (adj.sHR 3.7), higher consumption (top quartile) of cholesterol (adj.sHR 4.1), former (adj.sHR 4.3) or current (adj.sHR 3.5) smoking, or BMI ≥30 (adj.sHR 4.0) kg/m2. The effects of the G-allele on the risk of LRD were significantly attenuated in those with top quartile consumption of monounsaturated fat (adj.sHR 0.5) or coffee intake ≥3 cups/day (adj.sHR 0.09). Healthy eating index was inversely associated with liver-related death across all PNPLA3 genotypes (adj.sHR 0.94, 0.96, and 0.97 for CC, CG, and GG, respectively).

CONCLUSIONS

PNPLA3 is associated with liver-related death and this relationship is significantly modified by anthropometric and environmental factors.

IMPACT AND IMPLICATIONS

Light alcohol intake, dietary factors (healthy eating index, monounsaturated fat, cholesterol), coffee intake, smoking status, and BMI are independently associated with the risk of liver-related death. The increased inherited risk of liver-related death associated with PNPLA3 rs738409 appears to be attenuated by healthy eating index, monounsaturated fat, and coffee intake, and exacerbated by light alcohol intake, smoking, and BMI. Reducing harmful environmental exposures and increasing healthy eating habits may help mitigate the risk of liver-specific mortality even in those with high genetic risk.

PNPLA3 Polymorphism Is Inversely Correlated with Aortic Stiffness in Patients with Metabolic Dysfunction-Associated Steatotic Liver Disease Without Fibrosis

Metabolic dysfunction-associated steatotic liver disease (MASLD) corresponds to the condition of increased hepatic fat levels, which is the leading cause of hepatic failure and carcinoma. It is also an independent risk factor for cardiovascular disease (CVD) and mortality. MASLD can be due to obesity with insulin resistance and/or genetic predisposition, i.e., polymorphism in the patatin-like phospholipase domain-containing 3 (PNPLA3) gene. PNPLA3 polymorphism has been associated with increased hepatic fat levels, fibrosis, cirrhosis, and hepatocellular carcinoma, while its association with CVD remains to be fully understood. The aim of the current study was to examine whether the vascular phenotype of patients with MASLD differed between carriers and noncarriers of the PNPLA3 polymorphism. Adult patients with MASLD underwent clinical assessment, PNPLA3 genotyping, arterial tonometry for aortic stiffness measurement, and ultrasound examination of carotid arteries. In total, 117 patients with MASLD and no fibrosis (median hepatic stiffness was 4.71 kPa) were recruited. Carriers of the PNPLA3 polymorphism were younger and exhibited higher levels of ALT and APRI, as compared to wild-type subjects. On the other hand, carriers of the PNPLA3 polymorphism had not only a better metabolic profile (i.e., lower glucose and glycated hemoglobin) but also lower blood pressure, carotid intima-media thickness (IMT), and cardiovascular risk. In addition, PNPLA3 polymorphism was negatively correlated with aortic stiffness, which is a marker of arteriolosclerosis and vascular ageing. Our data are consistent with previous observations that in case of genetically-driven MASLD, there is an inverse association with common predictors of CVD. Our data support the view that the main contributors to CVD risk in patients with MASLD remain conventional cardiometabolic risk factors (i.e., age, glucose) that are more likely to be found in metabolic syndrome-related MASLD rather than genetically-driven MASLD, at least in the first stages of the disease.

Design and rationale for a global novel non-invasive screening observational study using genetics and non-invasive methodologies to identify at-risk MASLD participants: The ALIGN study

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a common chronic liver disease that is heterogenous in nature with various drivers and modifiers such as metabolic dysfunction and genetic factors. MASLD and the progressive subtype, metabolic dysfunction-associated steatohepatitis (MASH) represent the most rapidly increasing cause of liver-related mortality. There are limited treatment options for patients living with MASLD and MASH, various treatments with an array of different targets are under investigation and one therapeutic has been approved since the initiation of this study. Clinical trials investigating treatments for MASLD and MASH are associated with a high screen failure rate, driven largely by the regulatory required histological inclusion criteria for clinical trial eligibility. Other available clinically utilized biomarkers, typically referred to as non-invasive tests (NITs), can assess both the presence of steatosis and the severity of liver fibrosis in patients with MASLD and MASH in the clinic but are not yet approved over histological changes as endpoints for pivotal trials. However, the use of NITs have been demonstrated to increase the likelihood of meeting clinical trial entry criteria. All-Liver Interventional Global Network (ALIGN) is the first described multi-centre global observational screening study aimed at identifying individuals with a high likelihood of MASLD/MASH interested in participating in therapeutic clinical trials using non-invasive methodologies and genetic testing. This study represents a valuable prototype for industry and academic groups looking to evaluate large populations for MASH eligibility and interest in clinical trial participation.

[Cardiometabolic and genetic factors in the progression of metabolic dysfunction-associated steatotic liver disease]

AIM

To evaluate the contribution of cardiometabolicfactors and PNPLA3 I148M (rs738409 C>G) gene polymorphism to the development of compensated advanced chronic liver disease (cACLD) in patients with metabolic dysfunction-associated steatotic liver disease (MASLD).

MATERIALS AND METHODS

108 patients with MASLD were enrolled and formed the internal validation group; 30 patients with MASLD were selected for external validation. Anamnestic data, anthropometric and laboratory parameters and the presence of PNPLA3 gene polymorphism I148M (rs738409 C>G) were assessed. Steatosis was detected by assessing the controlled attenuation parameter. Liver elasticity was assessed by transient elastography. cACLD was detected when the liver stiffness was ≥8 kPa.

RESULTS

Statistically significant difference was observed in the internal validation group during comparison of the incidence of cACLD depending on the presence of arterial hypertension (odds ratio - OR 5.58; 95% confidence interval - CI 1.21-25.71), type 2 diabetes mellitus - T2DM (OR 4.58; 95% CI 1.59-13.21), obesity (OR 3.13; 95% CI 1.1-8.9), dyslipidemia (OR 6.12; 95% CI 1.33-28.19) and the mutant G allele of the PNPLA3 gene (OR 3.9; 95% CI 1.28-11.88). Patients with cACLD had significantly higher mean values of waist circumference (WC), alanine aminotransaminase, aspartate aminotransaminase, gamma-glutamyl transferase and triglycerides, non-invasive markers of steatosis and fibrosis. The compiled prognostic model demonstrated a direct relationship between the likelihood of developing cACLD and the presence of T2DM (adjusted odds ratio - AOR 3.28; 95% CI 0.62-17.33), dyslipidemia (AOR 5.89; 95% CI 1.21-28.67) and WC value (AOR 1.05; 95% CI 1.01-1.11). PNPLA3 I148M gene polymorphism did not significantly affect the development of late stages of the disease. External validation of the model showed its moderate diagnostic ability.

CONCLUSION

T2DM, dyslipidemia and WC values are the determining factors in the development of cACLD in patients with MASLD. The PNPLA3 I148M gene polymorphism has no leading importance for the development of the progressive course of MASLD in the studied cohort.

Impact of PNPLA3 I148M on Clinical Outcomes in Patients With MASLD

BACKGROUND AND AIMS

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a heterogenous clinical and histopathological entity, where multiple metabolic co-factors are intertwined with high interindividual variability. The impact and severity of each factor (including obesity and type 2 diabetes) define a systemic dysmetabolism that can lead to either advanced liver disease and its complication (including hepatocellular carcinoma and clinical events related to portal hypertension) or extrahepatic events: incident cardiovascular disease, chronic kidney disease and extrahepatic cancers. The balance between environmental factors and genetic susceptibility has unique implications in MASLD: the intermittent injury of metabolic co-factors, their fluctuation over time and their specific management, are counterbalanced by the presence of gene variants that can significantly impact the disease at multiple levels. The I148M variant in the PNPLA3 gene is the most investigated genetic susceptibility that induces a more severe steatohepatitis, enhanced fibrogenesis and can shape the incidence of long-term clinical events regardless of, or worsened by, other metabolic risk factors.

METHODS AND RESULTS

In this review, we will summarise the updated evidence on the natural history of MASLD accounting for classical metabolic risk factors, the role of PNPLA3 in clinical sub-phenotyping (e.g., 'lean MASLD'), impact on disease severity and fibrosis progression, as well as its role for prognostication, alone or in combination with non-invasive tools into polygenic risk scores.

Integrating PNPLA3 into clinical risk prediction

The PNPLA3-rs738409-G variant was the first common variant associated with hepatic fat accumulation and progression of metabolic dysfunction-associated steatotic liver disease (MASLD). Nevertheless, to date, the clinical translation of this discovery has been minimal because it has not yet been clearly demonstrated where the genetic information may play an independent and additional role in clinical risk prediction. In this mini-review, we will discuss the most relevant evidence regarding the potential integration of the PNPLA3 variant into scores and algorithms for liver disease diagnostics and risk stratification, specifically focusing on MASLD but also extending to liver diseases of other etiologies. The PNPLA3 variant adds little in diagnosing the current state of the disease, whether in terms of presence/absence of metabolic dysfunction-associated steatohepatitis or the stage of fibrosis. While it can play an important role in prediction, allowing for the early definition of risk profiles that enable tailored monitoring and interventions over time, this is most valuable when applied to populations with relatively high pre-test probability of having significant fibrosis based on either non-invasive tests (e.g. Fibrosis-4) or demographics (e.g. diabetes). Indeed, in this context, integrating FIB4 with the PNPLA3 genotype can refine risk stratification, though there is still no evidence that genetic information adds to liver stiffness determined by elastography. Similarly, in patients with known liver cirrhosis, knowing the PNPLA3 genotype can play a role in predicting the risk of hepatocellular carcinoma, while more doubts remain about the risk of decompensation.

An insight on the additive impact of type 2 diabetes mellitus and nonalcoholic fatty liver disease on cardiovascular consequences

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) are associated with a multifactorial complicated aetiology that is often coexisting and has a strong and distinct connection with cardiovascular diseases (CVDs). In order to accomplish effective and appropriate therapeutic strategies, a deeper understanding of the bidirectional interaction between NAFLD patients, NAFLD patients with T2DM, and NAFLD patients with CVDs is required to control the concomitant rise in prevalence of these conditions worldwide. This article also aims to shed light on the epidemiology and mechanisms behind the relationship between T2DM, NAFLD and the related cardiovascular consequences.

METHOD

Literature was collected from PubMed, Medline, Embase, Web of Science and Google scholar from inception to June, 2024. For surveying literature different combinations and formats of terms including NAFLD, NASH, T2DM and CVDs were used.

RESULTS

In the recent decade, clinical and epidemiological studies have been conducted and provide strong evidence that NAFLD is closely linked with CVD progression along with associated morbidity and mortality in both patients with and without T2DM. Several mechanistic approaches contribute to cardiovascular consequences and abnormalities in cardiac biomarkers in T2DM and NAFLD patients, including adipose tissue malfunction, mitochondrial dysfunction, the microbiota, genetic and epigenetic alterations contributing to insulin resistance, glucotoxicity and lipotoxicity.

CONCLUSION

The study reveals a complex interplay between diabetes, hepatic and cardiovascular complications, leading to significant morbidity and mortality in diabetic and NAFLD patients. This pandemic necessitates further research to identify mitigating variables and develop effective treatment approaches.

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

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

Genetic Risk Factors for Metabolic Dysfunction-Associated Steatotic Liver Disease

Metabolic dysfunction-associated steatotic liver disease (MASLD), is the most common cause of liver disease, and its burden on health systems worldwide continues to rise at an alarming rate. MASLD is a complex disease in which the interactions between susceptible genes and the environment influence the disease phenotype and severity. Advances in human genetics over the past few decades have provided new opportunities to improve our understanding of the multiple pathways involved in the pathogenesis of MASLD. Notably, the PNPLA3, TM6SF2, GCKR, MBOAT7 and HSD17B13 single nucleotide polymorphisms have been demonstrated to be robustly associated with MASLD development and disease progression. These genetic variants play crucial roles in lipid droplet remodeling, secretion of hepatic very low-density lipoprotein and lipogenesis, and understanding the biology has brought new insights to this field. This review discusses the current body of knowledge regarding these genetic drivers and how they can lead to development of MASLD, the complex interplay with metabolic factors such as obesity, and how this information has translated clinically into the development of risk prediction models and possible treatment targets.

AZD2693, a PNPLA3 antisense oligonucleotide, for the treatment of MASH in 148M homozygous participants: Two randomized phase I trials

BACKGROUND & AIMS

A common genetic variant (rs738409) encoding an isoleucine to methionine substitution at position 148 in the PNPLA3 protein is a determinant of hepatic steatosis, inflammation, fibrosis, cirrhosis, and liver-related mortality. AZD2693 is a liver-targeted antisense oligonucleotide against PNPLA3 mRNA. We evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics in single and multiple ascending dose studies.

METHODS

AZD2693 was assessed in 3D cultures of homozygous PNPLA3 148M primary human hepatocytes and mice expressing human PNPLA3. The single ascending dose study investigated 2-110 mg doses in overweight/mildly obese but otherwise healthy volunteers. The multiple ascending dose study investigated three monthly doses (25 mg, 50 mg and 80 mg) in participants with MRI-proton density fat fraction (MRI-PDFF) ≥7%. Changes in liver fat content were assessed at baseline, weeks 8 and 12 by MRI-PDFF. PNPLA3 mRNA and protein knockdown levels were evaluated for the 80 mg dose.

RESULTS

AZD2693 potently reduced PNPLA3 expression in human hepatocytes and livers of mice. Clinically, AZD2693 was generally well tolerated (no adverse events leading to discontinuation or treatment-related serious adverse events). Half-life was 14-33 days across investigated doses. A least-square mean liver PNPLA3 mRNA knockdown of 89% and reduction of protein levels demonstrated target engagement. Changes in hepatic steatosis at week 12 were -7.6% and -12.2% (placebo-corrected least-square means) for the 25 mg and 50 mg doses, respectively. There was a dose-dependent increase of polyunsaturated fatty acids in serum triglycerides and decreases vs. placebo in high-sensitivity C-reactive protein and interleukin 6.

CONCLUSIONS

AZD2693 reduced liver PNPLA3 with an acceptable safety and tolerability profile. These findings support the continued development of AZD2693.

IMPACT AND IMPLICATIONS

Clinical treatment options for metabolic dysfunction-associated steatohepatitis (MASH) are limited. The genetic risk factor with the largest effect size for progressing to poor liver-related outcomes in MASH is a single-nucleotide polymorphism in the gene PNPLA3 (p.I148M). In phase I single and multiple ascending dose studies, AZD2693, a liver-targeted antisense oligonucleotide, was well tolerated, reduced liver PNPLA3 mRNA and protein levels, and dose-dependently reduced liver fat content in homozygous PNPLA3 148M risk allele carriers. These data support continued development of AZD2693 as a potential precision medicine treatment for MASH. The phase IIb FORTUNA study is now ongoing.

CLINICAL TRIAL NUMBER

NCT04142424, NCT04483947.

Prevalence of metabolic dysfunction-associated steatotic liver disease and fibrosis defined by liver elastography in the United States using National Health and Nutrition Examination Survey 2017-March 2020 and August 2021-August 2023 data

BACKGROUND AND AIMS

Steatotic liver disease (SLD) is a significant public health burden. Previously, we estimated prepandemic SLD prevalence determined by transient elastography-assessed hepatic steatosis and fibrosis in the United States. We now estimate the prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) and examine associations with lifestyle, socioeconomic, and other factors.

APPROACH AND RESULTS

Liver stiffness and controlled attenuation parameters were assessed on 13,538 non-Hispanic White, non-Hispanic Black, non-Hispanic Asian, and Hispanic men and women aged 20 years and over in the National Health and Nutrition Examination Survey 2017 to March 2020 and August 2021 to August 2023. The prevalence of SLD (controlled attenuation parameter >300 dB/m) was 28.7%, fibrosis (liver stiffness >8 kPa) was 11.3%, and MASLD was 25.6%. Between the 2 survey cycles, the age-standardized SLD prevalence was not significantly different, MASLD prevalence decreased (26.8%-23.6%), and fibrosis prevalence increased (10.4%-12.7%). In multivariable-adjusted analysis, both MASLD and fibrosis were associated with diabetes, higher body mass index, higher waist-to-hip ratio, elevated blood pressure, and inversely associated with non-Hispanic Black race-ethnicity. MASLD was also associated with male sex, non-Hispanic Asian race-ethnicity, prediabetes, higher total cholesterol, lower HDL cholesterol, and greater sedentary lifestyle. Fibrosis was also associated with SLD, lower total cholesterol, and less education.

CONCLUSIONS

In the US population, MASLD and fibrosis prevalence are high along with obesity and diabetes. Our findings suggest that early detection of chronic liver disease and targeting lifestyle and other modifiable risk factors may slow disease progression toward advanced fibrosis and cirrhosis.

Metabolic issues in patients with metabolic dysfunction-associated steatohepatitis (MASH) and their impact on MASH recurrence following liver transplantation: A narrative review

Decompensated cirrhosis secondary to metabolic dysfunction-associated steatohepatitis (MASH) is not only a common indication for liver transplant (LT) but is becoming the leading cause of LT in postmenopausal women in the United States. Given the different complex mechanisms involved in the occurrence of MASH, it is being recognized as the hepatic manifestation of the metabolic syndrome. There are multiple metabolic issues associated with MASH, including obesity, DMT2, cardiovascular disease, and chronic kidney disease, which need to be addressed in the pretransplant and posttransplant setting for better patient outcomes. Recurrence of MASH following LT can occur due to many reasons including reversal of the catabolic state seen in cirrhosis, improvement in appetite, and the effect of certain post-LT medications on the graft; however, managing recurrence can be challenging and thus urges addressing these issues before transplant, in addition to recognizing, and treating them in the posttransplant setting. In this review, we discuss the various metabolic issues that face patients with MASH and the medical and surgical management options available to improve outcomes and reduce chances of recurrence.

Associations between serum levels of liver function biomarkers and all-cause and cause-specific mortality: a prospective cohort study

BACKGROUND

The liver plays critical roles in human health. Circulating level of liver function biomarkers may associate with the long-term and short-term mortality in general population.

METHODS

We used data from US National Health and Nutrition Examination Survey 1988-94 and 1999-2014. People aged ≥ 20 years with measured serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), alkaline phosphatase (ALP), total bilirubin (TB), and albumin (ALB) at baseline were included. All-cause and cause-specific mortality was identified from the National Death Index through 31 December 2015. Additive Cox regression models were applied to assess the correlation patterns between the serum level of these analytes and mortality risk.

RESULTS

A total of 44,508 participants were included; among them, 9,721 deaths occurred during a mean follow-up of 12.5 years. A "J-shaped" correlation was found between serum levels of ALT, AST, and TB and all-cause mortality. The risk of mortality monotonically increased with increasing GGT and ALP levels when their levels exceeded the valley points. A "L-shaped" correlation was found between the serum level of ALB and all-cause mortality. The correlation patterns were comparable among deaths from different causes and were consistent in subgroup and sensitivity analyses. While the integration of all six liver function biomarkers did not yield an optimal predictive performance for mortality (area under ROC curve = 0.706), it demonstrated a significantly better performance compared to any single biomarker..

CONCLUSION

Circulating liver function biomarkers showed diverse nonlinear correlations with mortality and may be utilized as part of a screening process to help identify individuals who may be at elevated risk of mortality.

Metabolic dysfunction-associated steatotic liver disease: a key factor in hepatocellular carcinoma therapy response

The conceptual evolution of non-alcoholic fatty liver disease (NAFLD) to what, since 2023, is called metabolic dysfunction-associated steatotic liver disease (MASLD) not only represents a change in the classification and definition of the disease but also reflects a broader understanding of this heterogeneous condition, which still with many aspects to refine. Although the definition of NAFLD can be interchanged to a high percentage with the new MASLD concept in different aspects, MASLD has been proposed as a relevant factor that influences the response to new immunotherapeutic treatments in the management of MASLD-related hepatocellular carcinoma (HCC), compared to HCC of other etiologies. This indicates that the etiology of HCC plays a relevant role in the prognosis, highlighting the urgency of evaluating treatment regimens for this subgroup of patients in upcoming clinical trials. A better understanding of the pathophysiology of MASLD generates strategies that not only aid in its management but also provide strategies to directly intervene in the carcinogenesis of HCC.

Genetics of Metabolic Dysfunction-associated Steatotic Liver Disease: The State of the Art Update

Recent advances in the genetics of metabolic dysfunction-associated steatotic liver disease (MASLD) are gradually revealing the mechanisms underlying the heterogeneity of the disease and have shown promising results in patient stratification. Genetic characterization of the disease has been rapidly developed using genome-wide association studies, exome-wide association studies, phenome-wide association studies, and whole exome sequencing. These advances have been powered by the increase in computational power, the development of new analytical algorithms, including some based on artificial intelligence, and the recruitment of large and well-phenotyped cohorts. This review presents an update on genetic studies that emphasize new biological insights from next-generation sequencing approaches. Additionally, we discuss innovative methods for discovering new genetic loci for MASLD, including rare variants. To comprehensively manage MASLD, it is important to stratify risks. Therefore, we present an update on phenome-wide association study associations, including extreme phenotypes. Additionally, we discuss whether polygenic risk scores and targeted sequencing are ready for clinical use. With particular focus on precision medicine, we introduce concepts such as the interplay between genetics and the environment in modulating genetic risk with lifestyle or standard therapies. A special chapter is dedicated to gene-based therapeutics. The limitations of approved pharmacological approaches are discussed, and the potential of gene-related mechanisms in therapeutic development is reviewed, including the decision to perform genetic testing in patients with MASLD.

PNPLA3 rs738409, age, diabetes, sex, and advanced fibrosis jointly contribute to the risk of major adverse liver outcomes in metabolic dysfunction-associated steatotic liver disease

BACKGROUND AND AIMS

The patatin-like phospholipase domain-containing protein 3 ( PNPLA3 ) rs738409 variant is associated with steatotic liver disease and its progression. We examined the association between PNPLA3 and the development of major adverse liver outcomes (MALOs) and how nonmodifiable and modifiable conditions modify this relationship.

APPROACH AND RESULTS

A total of 2075 adults with biopsy-confirmed metabolic dysfunction-associated steatotic liver disease (MASLD) were enrolled in the metabolic dysfunction-associated steatohepatitis Clinical Research Network (MASH CRN) studies and followed prospectively until death, transplant, or withdrawal of consent. One hundred four MALOs were recorded during an average of 4.3 years. PNPLA3 G-allele (Adj. sub-hazard ratio (sHR): 1.4, 95% CI: 1.07-1.8), advanced fibrosis (AF) (Adj. sHR: 7.8, 95% CI: 4.4-13.8), age >60 years (Adj. sHR: 2.9, 95% CI: 1.3-6.8), and type 2 diabetes mellitus (Adj. sHR: 2.8, 95% CI: 1.8-4.2) were associated with MALO. Among participants with AF, those carrying the G-allele displayed the highest cumulative incidence of MALO (85%) versus noncarriers (53%), p =0.03, and p -value for interaction <0.01. The strength of the association between PNPLA3 and MALO was statistically significantly greater among older than 60 years (sHR: 2.1, 95% CI: 1.5-2.8), women (sHR: 1.4, 95% CI: 1.1-1.9), and those with AF (sHR: 1.9, 95% CI: 1.5-2.4) or type 2 diabetes mellitus (sHR: 2.1, 95% CI: 1.5-2.8) as compared with their counterparts, p -value for interaction between PNPLA3 and each factor<0.01.

CONCLUSIONS

The deleterious effects of PNPLA3 rs738409 on the risk of MALO are significantly worsened by AF, age, type 2 diabetes mellitus, and sex.

Fibrosis-4 Score Is Associated with Mortality in Hemodialysis Patients with Chronic Viral Hepatitis: A Retrospective Study

BACKGROUND

Chronic hepatitis B and C infections are major causes of morbidity and mortality in end-stage kidney disease (ESKD) patients on hemodialysis (HD). The Fibrosis-4 (FIB-4) score is a non-invasive method to evaluate chronic liver disease. However, it is unclear whether there is a connection between the FIB-4 score and major adverse cardiovascular events (MACEs) and mortality in patients on HD. This study investigates the relationship between FIB-4 scores, MACEs, and mortality in HD patients.

METHODS

A 5-year retrospective study included 198 HD patients with chronic hepatitis B and C from Chang Gung Memorial Hospital. FIB-4 scores were categorized into high (>2.071), middle (1.030~2.071), and low (<1.030) tertiles for cross-sectional analyses. MACEs and mortality were tracked longitudinally.

RESULTS

Patients with high FIB-4 scores had lower hemoglobin and albumin levels. Cox multivariate analysis showed that high FIB-4 scores (aHR: 1.589) and diabetes mellitus (aHR: 5.688) were significant factors for all-cause mortality. The optimal FIB-4 score for 5-year mortality was 2.942. FIB-4 scores were not significant for predicting 5-year MACEs.

CONCLUSIONS

High FIB-4 scores are associated with increased 5-year all-cause mortality risk in HD patients with chronic hepatitis virus infection.

Compensated advanced chronic liver disease in patients with metabolic dysfunction-associated steatotic liver disease: association with cardiometabolic factors

Aim. Тo study cardiometabolic factors and the PNPLA3 I148M (rs738409 C>G) gene polymorphism in association with the compensated advanced chronic liver disease (cACLD) in patients with metabolic dysfunction-associated steatotic liver disease (MASLD).

Materials and methods. А retrospective cross-sectional study was conducted. The total of 108 patients with MASLD (33 men and 75 women aged 28 to 89 years) involved were divided into two groups based on results of transient elastography: group 1 – with the presence of cACLD (liver stiffness ≥ 8.0 kPa) – 18 patients and group 2 – without cACLD (<8.0 kPa) – 90 patients. Cardiometabolic risk factors and the PNPLA3 I148M (rs738409 C>G) gene polymorphism were studied in both groups. Odds ratios (OR) and 95% confidence intervals (CI) were calculated, and a logistic regression model was constructed for the detection of cACLD.

Results. Compared to group 2, patients with cACLD had statistically significant higher prevalence of: arterial hypertension (p < 0.05), type 2 diabetes mellitus (p < 0.01), obesity (p < 0.05), dyslipidemia (p < 0.05), and PNPLA3 gene polymorphism (p < 0.05). The OR for cACLD in individuals with arterial hypertension was 5.58 (95% CI: 1.21–25.71; p < 0.05), with type 2 diabetes mellitus – 4.58 (95% CI: 1.59–13.21; p < 0.01), with obesity – 3.83 (95% CI: 1.17–12.52; p < 0.05), with dyslipidemia – 6.12 (95% CI: 1.33–28.20; p < 0.05), in the presence of a polymorphic variant of the PNPLA3 gene in a hetero or homozygous state – 3.9 (95% CI: 1.28–11.89; p < 0.05). The binary logistic regression model for detecting cACLD included type 2 diabetes mellitus, dyslipidemia, and waist circumference. The area under the ROC curve was 0.81 (95% CI: 0.70–0.92), sensitivity was 72.2%, specificity was 74.4%, and accuracy was 84.3%.

Conclusion. Type 2 diabetes mellitus, dyslipidemia, and waist circumference are the determining factors for the development of cACLD in patients with MASLD. The PNPLA3 I148M gene polymorphism does not play a leading role in the development of progressive MASLD in the study cohort.

Team players in the pathogenesis of metabolic dysfunctions-associated steatotic liver disease: The basis of development of pharmacotherapy

Nutrient metabolism is regulated by several factors. Social determinants of health with or without genetics are the primary regulator of metabolism, and an unhealthy lifestyle affects all modulators and mediators, leading to the adaptation and finally to the exhaustion of cellular functions. Hepatic steatosis is defined by presence of fat in more than 5% of hepatocytes. In hepatocytes, fat is stored as triglycerides in lipid droplet. Hepatic steatosis results from a combination of multiple intracellular processes. In a healthy individual nutrient metabolism is regulated at several steps. It ranges from the selection of nutrients in a grocery store to the last step of consumption of ATP as an energy or as a building block of a cell as structural component. Several hormones, peptides, and genes have been described that participate in nutrient metabolism. Several enzymes participate in each nutrient metabolism as described above from ingestion to generation of ATP. As of now several publications have revealed very intricate regulation of nutrient metabolism, where most of the regulatory factors are tied to each other bidirectionally, making it difficult to comprehend chronological sequence of events. Insulin hormone is the primary regulator of all nutrients' metabolism both in prandial and fasting states. Insulin exerts its effects directly and indirectly on enzymes involved in the three main cellular function processes; metabolic, inflammation and repair, and cell growth and regeneration. Final regulators that control the enzymatic functions through stimulation or suppression of a cell are nuclear receptors in especially farnesoid X receptor and peroxisome proliferator-activated receptor/RXR ligands, adiponectin, leptin, and adiponutrin. Insulin hormone has direct effect on these final modulators. Whereas blood glucose level, serum lipids, incretin hormones, bile acids in conjunction with microbiota are intermediary modulators which are controlled by lifestyle. The purpose of this review is to overview the key players in the pathogenesis of metabolic dysfunction-associated steatotic liver disease (MASLD) that help us understand the disease natural course, risk stratification, role of lifestyle and pharmacotherapy in each individual patient with MASLD to achieve personalized care and target the practice of precision medicine. PubMed and Google Scholar databases were used to identify publication related to metabolism of carbohydrate and fat in states of health and disease states; MASLD, cardiovascular disease and cancer. More than 1000 publications including original research and review papers were reviewed.

Polygenic risk score of metabolic dysfunction-associated steatotic liver disease amplifies the health impact on severe liver disease and metabolism-related outcomes

BACKGROUND

Although the inherited risk factors associated with fatty liver disease are well understood, little is known about the genetic background of metabolic dysfunction-associated steatotic liver disease (MASLD) and its related health impacts. Compared to non-alcoholic fatty liver disease (NAFLD), MASLD presents significantly distinct diagnostic criteria, and epidemiological and clinical features, but the related genetic variants are yet to be investigated. Therefore, we conducted this study to assess the genetic background of MASLD and interactions between MASLD-related genetic variants and metabolism-related outcomes.

METHODS

Participants from the UK Biobank were grouped into discovery and replication cohorts for an MASLD genome-wide association study (GWAS), and base and target cohorts for polygenic risk score (PRS) analysis. Autosomal genetic variants associated with NAFLD were compared with the MASLD GWAS results. Kaplan-Meier and Cox regression analyses were used to assess associations between MASLD and metabolism-related outcomes.

RESULTS

Sixteen single-nucleotide polymorphisms (SNPs) were identified at genome-wide significance levels for MASLD and duplicated in the replication cohort. Differences were found after comparing these SNPs with the results of NAFLD-related genetic variants. MASLD cases with high PRS had a multivariate-adjusted hazard ratio of 3.15 (95% confidence interval, 2.54-3.90) for severe liver disease (SLD), and 2.81 (2.60-3.03) for type 2 diabetes mellitus. The high PRS amplified the impact of MASLD on SLD and extrahepatic outcomes.

CONCLUSIONS

High PRS of MASLD GWAS amplified the impact of MASLD on SLD and metabolism-related outcomes, thereby refining the process of identification of individuals at high risk of MASLD. Supplementation of this process with relevant genetic backgrounds may lead to more effective MASLD prevention and management.

Clinical and genetic risk factors for progressive fibrosis in metabolic dysfunction-associated steatotic liver disease

BACKGROUND

Fibrosis-4 (FIB4) is a recommended noninvasive test to assess hepatic fibrosis among patients with metabolic dysfunction-associated steatotic liver disease (MASLD). Here, we used FIB4 trajectory over time (ie, "slope" of FIB4) as a surrogate marker of liver fibrosis progression and examined if FIB4 slope is associated with clinical and genetic factors among individuals with clinically defined MASLD within the Million Veteran Program Cohort.

METHODS

In this retrospective cohort study, FIB4 slopes were estimated through linear regression for participants with clinically defined MASLD and FIB4 <2.67 at baseline. FIB4 slope was correlated with demographic parameters and clinical outcomes using logistic regression and Cox proportional hazard models. FIB4 slope as a quantitative phenotype was used in a genome-wide association analysis in ancestry-specific analysis and multiancestry meta-analysis using METAL.

RESULTS

FIB4 slopes, generated from 98,361 subjects with MASLD (16,045 African, 74,320 European, and 7996 Hispanic), showed significant associations with sex, ancestry, and cardiometabolic risk factors (p < 0.05). FIB4 slopes also correlated strongly with hepatic outcomes and were independently associated with time to cirrhosis. Five genetic loci showed genome-wide significant associations (p < 5 × 10-8) with FIB4 slope among European ancestry subjects, including 2 known (PNPLA3 and TM6SF2) and 3 novel loci (TERT 5.1 × 10-11; LINC01088, 3.9 × 10-8; and MRC1, 2.9 × 10-9).

CONCLUSIONS

Linear trajectories of FIB4 correlated significantly with time to progression to cirrhosis, with liver-related outcomes among individuals with MASLD and with known and novel genetic loci. FIB4 slope may be useful as a surrogate measure of fibrosis progression.

Are we ready for genetic testing in metabolic dysfunction-associated steatotic liver disease?

Metabolic dysfunction-associated steatotic liver disease (MASLD), with its steadily increasing prevalence, represents now a major problem in public health. A proper referral could benefit from tools allowing more precise risk stratification. To this end, in recent decades, several genetic variants that may help predict and refine the risk of development and progression of MASLD have been investigated. In this review, we aim to discuss the role genetics in MASLD plays in everyday clinical practice. We performed a comprehensive literature search of PubMed for relevant publications. Available evidence highlights the emergence of genetic-based noninvasive algorithms for diagnosing fatty liver, metabolic dysfunction-associated steatohepatitis, fibrosis progression and occurrence of liver-related outcomes including hepatocellular carcinoma. Nevertheless, their accuracy is not optimal and application in everyday clinical practice remains challenging. Furthermore, susceptible genetic markers have recently become subjects of great scientific interest as therapeutic targets in precision medicine. In conclusion, decisional algorithms based on genetic testing in MASLD to facilitate the clinician decisions on management and treatment are under growing investigation and could benefit from artificial intelligence methodology.

No association of NAFLD-related polymorphisms in PNPLA3 and TM6SF2 with all-cause and cardiovascular mortality in an Austrian population study

BACKGROUND AND AIMS

Single-nucleotide-polymorphisms in PNPLA3-rs738409 and the TM6SF2-rs58542926, associated with metabolic-dysfunction-associated fatty liver disease (MAFLD), have been discussed as potentially protective for cardiovascular diseases. Therefore, we aimed to study the associations of PNPLA3/TM6SF2 variants with MAFLD and cardiovascular risk in a population-based sample of asymptomatic patients.

METHODS

The study cohort comprised 1742 patients of European decent aged 45-80 years from a registry study undergoing screening colonoscopy for colorectal cancer between 2010 and 2014. SCORE2 and Framingham risk score calculated to assess cardiovascular risk. Data on survival were obtained from the national death registry RESULTS: Half of included patients were male (52%, 59 ± 10 years), 819 (47%) carried PNPLA3‑G and 278 (16%) TM6SF2-T-alleles. MAFLD (PNPLA3‑G-allele: 46% vs. 41%, p = 0.041; TM6SF2‑T-allele: 54% vs. 42%, p < 0.001) was more frequent in patients harbouring risk alleles with both showing independent associations with MAFLD on multivariable binary logistic regression analysis. While median Framingham risk score was lower in PNPLA3‑G-allele carriers (10 vs. 8, p = 0.011), SCORE2 and established cardiovascular diseases were similar across carriers vs. non-carriers of the respective risk-alleles. During a median follow-up of 9.1 years, neither PNPLA3‑G-allele nor TM6SF2‑T-allele was associated with overall nor with cardiovascular mortality.

CONCLUSION

Carriage of PNPLA3/TM6SF2 risk alleles could not be identified as significant factor for all-cause or cardiovascular mortality in asymptomatic middle-aged individuals undergoing screening colonoscopy.

NAFLD in the 21st Century: Current Knowledge Regarding Its Pathogenesis, Diagnosis and Therapeutics

Non-alcoholic fatty liver disease (NAFLD) is a major public health issue worldwide. It is the most common liver disease in Western countries, andits global prevalence is estimated to be up to 35%. However, its diagnosis may be elusive, because liver biopsy is relatively rarely performed and usually only in advanced stages of the disease. Therefore, several non-invasive scores may be applied to more easily diagnose and monitor NAFLD. In this review, we discuss the various biomarkers and imaging scores that could be useful in diagnosing and managing NAFLD. Despite the fact that general measures, such as abstinence from alcohol and modulation of other cardiovascular disease risk factors, should be applied, the mainstay of prevention and management is weight loss. Bariatric surgery may be suggested as a means to confront NAFLD. In addition, pharmacological treatment with GLP-1 analogues or the GIP agonist tirzepatide may be advisable. In this review, we focus on the utility of GLP-1 analogues and GIP agonists in lowering body weight, their pharmaceutical potential, and their safety profile, as already evidenced inanimal and human studies. We also elaborate on other options, such as the use of vitamin E, probiotics, especially next-generation probiotics, and prebiotics in this context. Finally, we explore future perspectives regarding the administration of GLP-1 analogues, GIP agonists, and probiotics/prebiotics as a means to prevent and combat NAFLD. The newest drugs pegozafermin and resmetiron, which seem to be very promising, arealso discussed.

Relevance of PNPLA3, TM6SF2, HSD17B13, and GCKR Variants to MASLD Severity in an Egyptian Population

Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD), is a frequent clinical condition globally. Single nucleotide polymorphisms (SNPs) associated with NAFLD have been proposed in the literature and based on bioinformatic screening. The association between NAFLD and genetic variants in Egyptians is still unclear. Hence, we sought to investigate the association of some genetic variants with NAFLD in Egyptians. Egyptians have been categorized into either the MASLD group (n = 205) or the healthy control group (n = 187). The severity of hepatic steatosis and liver fibrosis was assessed by a Fibroscan device. TaqMan-based genotyping assays were employed to explore the association of selected SNPs with MASLD. PNPLA3 rs738409 C>G variant is associated with the presence of MASLD with liver fibrosis, the severity of both hepatic steatosis and liver fibrosis, increased systolic and diastolic blood pressure and increased alanine aminotransferase (all p < 0.05), while the TM6SF2 rs58542926 C>T, HSD17B13 rs9992651 G>A, and GCKR rs1260326 T>C variants were not (all p > 0.05). The TM6SF2 rs58542926 T allele is associated with increased fasting blood glucose and a decreased waist circumference. The GCKR rs1260326 C allele is associated with decreased aspartate transaminase and diastolic blood pressure (all p < 0.05). Only after adjusting for the risk factors (age, sex, BMI, WC, HDL, TG, diabetes mellitus, and hypertension) F2 liver fibrosis score is negatively correlated with the HSD17B13 rs9992651 GA genotype. This study offers evidence for the association of the PNPLA3 rs738409 C>G variant with MASLD among Egyptians and for the association of the PNPLA3 rs738409 G allele, the TM6SF2 rs58542926 T allele, and the GCKR rs1260326 C allele with some parameters of cardiometabolic criteria.

Natural history of metabolic dysfunction-associated steatotic liver disease

Metabolic dysfunction-associated steatotic liver disease (MASLD), which has been the term for non-alcoholic fatty liver disease (NAFLD) since June 2023, represents the most common liver disease worldwide and is a leading cause of liver-related morbidity and mortality. A thorough knowledge of the disease's natural history is required to promptly stratify patients' risks, since MASLD is a multifaceted disorder with a broad range of clinical phenotypes. The histological disease spectrum ranges from isolated hepatic steatosis, currently named as metabolic dysfunction-associated steatotic liver (MASL), to metabolic dysfunction-associated steatohepatitis (MASH) and eventually may accumulate hepatic fibrosis and develop cirrhosis and/or hepatocellular carcinoma (HCC). Several risk factors for fibrosis progression have been identified, while the disease's progression displays notable dynamism and bidirectionality. When compared to the general population, all MASLD histological stages are substantially related with greater overall mortality, and this association exhibits a disease severity-dependent pattern. Interestingly, the fibrosis stage is the most accurate predictor of mortality among MASLD patients. The mortality attributed to MASLD predominantly stems from issues linked with the liver and cardiovascular system, as well as HCC and extrahepatic cancers. In light of the disease natural course, it is crucial to prioritize the identification of at-risk patients for disease progression in order to effectively address and change modifiable risk factors, hence mitigating disease complications. Further investigation is required to define the phenotype of rapid progressors more precisely as well as to improve risk stratification for HCC in non-cirrhotic individuals.

Integrated traditional Chinese and Western medicine in the prevention and treatment of non-alcoholic fatty liver disease: future directions and strategies

Traditional Chinese medicine (TCM) has been widely used for several centuries for metabolic diseases, including non-alcoholic fatty liver disease (NAFLD). At present, NAFLD has become the most prevalent form of chronic liver disease worldwide and can progress to non-alcoholic steatohepatitis (NASH), cirrhosis, and even hepatocellular carcinoma. However, there is still a lack of effective treatment strategies in Western medicine. The development of NAFLD is driven by multiple mechanisms, including genetic factors, insulin resistance, lipotoxicity, mitochondrial dysfunction, endoplasmic reticulum stress, inflammation, gut microbiota dysbiosis, and adipose tissue dysfunction. Currently, certain drugs, including insulin sensitizers, statins, vitamin E, ursodeoxycholic acid and betaine, are proven to be beneficial for the clinical treatment of NAFLD. Due to its complex pathogenesis, personalized medicine that integrates various mechanisms may provide better benefits to patients with NAFLD. The holistic view and syndrome differentiation of TCM have advantages in treating NAFLD, which are similar to the principles of personalized medicine. In TCM, NAFLD is primarily classified into five types based on clinical experience. It is located in the liver and is closely related to spleen and kidney functions. However, due to the multi-component characteristics of traditional Chinese medicine, its application in the treatment of NAFLD has been considerably limited. In this review, we summarize the advances in the pathogenesis and treatment of NAFLD, drawn from both the Western medicine and TCM perspectives. We highlight that Chinese and Western medicine have complementary advantages and should receive increased attention in the prevention and treatment of NAFLD.

Association of liver fibrosis with extrahepatic cancer in steatotic liver disease patients with PNPLA3 I148M GG genotype

The impacts of patatin-like phospholipase domain-containing protein 3 (PNPLA3) I148M-rs738409, methylenetetrahydrofolate reductase (MTHFR) Ala222Val-rs1801133, and aldehyde dehydrogenase 2 (ALDH2) Glu504Lys-rs671 on the outcomes of Taiwanese patients with steatotic liver disease (SLD) have remained elusive. An 8-year prospective cohort study of patients with (n = 546) and without (n = 580) SLD (controls) was undertaken in a Taiwanese tertiary care center. The 546 SLD patients comprised 306 (56.0%) men and 240 (44.0%) women with mean ages of 53.3 and 56.4 years, respectively. Compared with the controls, SLD patients had an increased frequency of the PNPLA3 I148M-rs738409 GG genotype (25.5 vs. 5.9%, p = 0.001). Among the SLD patients, 236 (43.1%) suffered cardiovascular events, 52 (9.5%) showed extrahepatic cancers, 13 (2.38%) experienced hepatic events, including hepatocellular carcinoma (n = 3, 0.5%) and liver cirrhosis (n = 8, 1.47%), and none died. The Fibrosis-4 (FIB-4) scores were associated with extrahepatic cancer (hazard ratio [HR] 1.325; 95% confidence interval [CI], 1.038-1.691) and cirrhosis development (HR 1.532; 95% CI, 1.055-2.224), and the PNPLA3 I148M-rs738409 G allele (β = 0.158, 95% CI, 0.054-0.325) was associated with the FIB-4 score. Stratified analyses showed that the impact of the FIB-4 score on extrahepatic cancer development was evident only in SLD patients with the PNPLA3 I148M-rs738409 GG genotype (HR 1.543; 95% CI, 1.195-1.993) and not in patients with the GC or CC genotype. Moreover, the ALDH2 Glu504Lys-rs671 G allele had a dose-dependent effect on alcoholism, and the MTHFR and ALDH2 genotypes were not significantly associated with SLD patient outcomes. In conclusion, special vigilance should be exercised for emerging extrahepatic cancer in SLD patients with the PNPLA3 I148M-rs738409 GG genotype and high FIB-4 scores.

Effect of donor HSD17B13 genotype on patient survival after liver transplant: a retrospective cohort study

Background

Several genetic variants are associated with chronic liver disease. The role of these variants in outcomes after liver transplantation (LT) is uncertain. The aim of this study was to determine if donor genotype at risk-associated variants in PNPLA3 (rs738409 C>G, p.I148M) and HSD17B13 (rs72613567 T>TA; rs80182459, p.A192Lfs∗8) influences post-LT survival.

Methods

In this retrospective cohort study, data on 2346 adults who underwent first-time LT between January 1, 1999 and June 30, 2020 and who had donor DNA samples available at five large Transplant Immunology Laboratories in Texas, USA, were obtained from the United Network for Organ Sharing (UNOS). Duplicates, patients with insufficient donor DNA for genotyping, those who were <18 years of age at the time of transplant, had had a previous transplant or had missing genotype data were excluded. The primary outcomes were patient and graft survival after LT. The association between donor genotype and post-LT survival was examined using Kaplan-Meier method and multivariable-adjusted Cox proportional hazards models.

Findings

Median age of LT recipients was 57 [interquartile range (IQR), 50-62] years; 837 (35.7%) were women; 1362 (58.1%) White, 713 (30.4%) Hispanic, 182 (7.8%) Black/African-American. Median follow-up time was 3.95 years. Post-LT survival was not affected by donor PNPLA3 genotype but was significantly reduced among recipients of livers with two HSD17B13 loss-of-function (LoF) variants compared to those receiving livers with no HSD17B13 LoF alleles (unadjusted one-year survival: 82.6% vs 93.9%, P < 0.0001; five-year survival: 73.1% vs 82.9%, P = 0.0017; adjusted hazard ratio [HR], 2.25; 95% CI, 1.61-3.15 after adjustment for recipient age, sex, and self-reported ethnicity). Excess mortality was restricted to those receiving steroid induction immunosuppression (crude 90-day post-LT mortality, 9.3% [95% CI, 1.9%-16.1%] vs 1.9% [95% CI, 0.9%-2.9%] in recipients of livers with two vs no HSD17B13 LoF alleles, P = 0.0012; age, sex, and ethnicity-adjusted HR, 2.85; 95% CI, 1.72-4.71, P < 0.0001). No reduction was seen among patients who did not receive steroid induction (90-day mortality 3.1% [95% CI, 0%-7.3%] vs 2% [95% CI, 0.9%-3.1%], P = 0.65; adjusted HR, 1.17; 95% CI, 0.66-2.08, P = 0.60).

Interpretation

Donor HSD17B13 genotype adversely affects post-LT survival in patients receiving steroid induction. Additional studies are required to confirm this association.

Funding

The National Institutes of Health and American Society of Transplant Surgeons Collaborative Scientist Grant.

PROTAC Beyond Cancer- Exploring the New Therapeutic Potential of Proteolysis Targeting Chimeras

In the realm of oncology, the transformative impact of PROTAC (PROteolysis TAgeting Chimeras) technology has been particularly pronounced since its introduction in the 21st century. Initially conceived for cancer treatment, PROTACs have evolved beyond their primary scope, attracting increasing interest in addressing a diverse array of medical conditions. This expanded focus includes not only oncological disorders but also viral infections, bacterial ailments, immune dysregulation, neurodegenerative conditions, and metabolic disorders. This comprehensive review explores the broadening landscape of PROTAC application, highlighting ongoing developments and innovations aimed at deploying these molecules across a spectrum of diseases. Careful consideration of the design challenges associated with PROTACs reveals that, when appropriately addressed, these compounds present significant advantages over traditional therapeutic approaches, positioning them as promising alternatives. To evaluate the efficacy of PROTAC molecules, a diverse array of assays is employed, ranging from High-Throughput Imaging (HTI) assays to Cell Painting assays, CRBN engagement assays, Fluorescence Polarization assays, amplified luminescent proximity homogeneous assays, Timeresolved fluorescence energy transfer assays, and Isothermal Titration Calorimetry assays. These assessments collectively contribute to a nuanced understanding of PROTAC performance. Looking ahead, the trajectory of PROTAC technology suggests its potential recognition as a versatile therapeutic strategy for an expansive range of medical conditions. Ongoing progress in this field sets the stage for PROTACs to emerge as valuable tools in the multifaceted landscape of medical treatments.

Metabolic disorders across the body mass index spectrum in a Colombian population with nonalcoholic fatty liver disease

BACKGROUND AND AIMS

The relationship between obesity and nonalcoholic fatty liver disease (NAFLD) has long been established, and the prevalence of both conditions has grown together. Recent interest in NAFLD in nonobese individuals has led to an increasing number of studies, especially in Asia. Despite the fact that the prevalence of NAFLD in Latin America is one of the highest in the world, there is a lack of information on lean NAFLD populations from the region. The aim of the present study was to assess the risk of metabolic comorbidities across the whole body mass index spectrum when nonalcoholic steatohepatitis (NASH) was first diagnosed in a Latin American population.

METHODS

A single-center, cross-sectional study on Colombian patients newly diagnosed with NAFLD, within the time frame of 2010-2020, compared their metabolic biochemical profile, liver enzymes, risk of prevalent metabolic abnormalities, and liver disease.

RESULTS

Data from 300 patients were collected. Ninety-two percent of the patients were men and the median patient age was 47 (IQR 20) years. We found no significant differences in the biochemical, metabolic profile, or liver enzyme plasma concentration between lean, overweight, and obese individuals. Obese patients had significantly higher LDL cholesterol, and a higher risk of dyslipidemia (OR 1.86, 95% CI 1.14-3.05). Every 1kg increase in body weight increased the risk of having NASH by 2% (95% CI 2-4).

CONCLUSIONS

We evaluated the metabolic risk across the entire body mass index spectrum in a Colombian cohort with NAFLD and presented the characteristics of what we believe is the first Latin American lean NAFLD population to be described.

Familial coaggregation of MASLD with hepatocellular carcinoma and adverse liver outcomes: Nationwide multigenerational cohort study

BACKGROUND & AIMS

Metabolic dysfunction-associated steatotic liver disease (MASLD; formerly NAFLD) is the fastest growing cause of hepatocellular carcinoma (HCC) worldwide. However, whether family members of individuals with MASLD also share an increased risk of developing HCC is unknown.

METHODS

This nationwide multigenerational cohort study involved family members of all Swedish adults diagnosed with biopsy-proven MASLD (1969-2017), and matched general population comparators. Using the Swedish Multi-generation Register, we identified 38,018 first-degree relatives (FDRs: parents, siblings, offspring) and 9,381 spouses of patients with MASLD, as well as 197,303 comparator FDRs and 47,572 comparator spouses. We used Cox proportional hazards models to calculate adjusted hazard ratios (aHRs) for HCC, major adverse liver outcomes (cirrhosis, decompensated liver disease or liver transplantation), liver-related mortality, extrahepatic cancer, and non-liver-related mortality.

RESULTS

Over a median of 17.6 years, the rate of the primary outcome HCC was higher in MASLD FDRs vs. comparator FDRs (13 vs. 8/100,000 person-years [PY]; aHR 1.80, 95% CI 1.36-2.37). The HCC risk was further increased in FDRs of individuals with liver fibrosis/cirrhosis (aHR 2.14, 95% CI 1.07-4.27; PHeterogeneity = 0.03). MASLD FDRs also had higher rates of major adverse liver outcomes (73 vs. 51/100,000 PY; aHR 1.52, 95% CI 1.36-1.69) and liver-related mortality (20 vs. 11/100,000 PY; aHR 2.14, 95% CI 1.67-2.74). MASLD FDRs with any concomitant chronic liver condition experienced accelerated progression of liver disease (aHR 1.47, 95% CI 1.29-1.67). MASLD spouses were at higher risks of major adverse liver outcomes (86 vs. 74/100,000 PY; aHR 1.23, 95% CI 1.01-1.51) and liver-related mortality (25 vs. 19/100,000 PY; aHR 1.93, 95% CI 1.15-3.23), but not of HCC (aHR 1.43, 95% CI 0.87-2.35).

CONCLUSIONS

There is distinct familial clustering of adverse liver-related outcomes in families of individuals with biopsy-proven MASLD, with higher relative risks of HCC, progressive liver disease, and liver-related mortality, but absolute risks are low.

IMPACT AND IMPLICATIONS

Metabolic dysfunction-associated steatotic liver disease (MASLD; formerly termed NAFLD) clusters in families with high genetic susceptibility and shared environmental risk factors, but the risks of developing hepatocellular carcinoma and other major liver-related outcomes in family members of individuals with MASLD are largely unknown. This large nationwide multigenerational cohort study involving family members (first-degree relatives and spouses) of individuals with biopsy-proven MASLD and of matched general population comparators found slightly increased risks of hepatocellular carcinoma in first-degree relatives, and of developing cirrhosis and liver-related mortality in all family members of individuals with biopsy-proven MASLD. The findings of this study provide large-scale evidence to inform clinical practice guidelines for recommendations on the early identification of individuals at higher risk of liver-related morbidity and mortality.

Prognostication in NAFLD: physiological bases, clinical indicators, and newer biomarkers

Non-alcoholic fatty liver disease (NAFLD) is becoming an epidemic in Western countries. Notably, while the majority of NAFLD patients will not evolve until advanced liver disease, a minority of them will progress towards liver-related events. Therefore, risk stratification and prognostication are emerging as fundamental in order to optimize human and economic resources for the care of these patients.Liver fibrosis has been clearly recognized as the main predictor of poor hepatic and extrahepatic outcomes. However, a prediction based only on the stage of fibrosis is near-sighted and static, as it does not capture the propensity of disease to further progress, the speed of progression and their changes over time. These determinants, which result from the interaction between genetic predisposition and acquired risk factors (obesity, diabetes, etc.), express themselves in disease activity, and can be synthesized by biomarkers of hepatic inflammation and fibrogenesis.In this review, we present the currently available clinical tools for risk stratification and prognostication in NAFLD specifically with respect to the risk of progression towards hard hepatic outcomes, i.e., liver-related events and death. We also discuss about the genetic and acquired drivers of disease progression, together with the physiopathological bases of their come into action. Finally, we introduce the most promising biomarkers in the direction of repeatedly assessing disease activity over time, mainly in response to future therapeutic interventions.

Therapeutic opportunities for the treatment of NASH with genetically validated targets

The identification of genetic variants associated with fatty liver disease (FLD) from genome-wide association studies started in 2008 when single nucleotide polymorphisms in PNPLA3, the gene encoding patatin-like phospholipase domain-containing 3, were found to be associated with altered hepatic fat content. Since then, several genetic variants associated with protection from, or an increased risk of, FLD have been identified. The identification of these variants has provided insight into the metabolic pathways that cause FLD and enabled the identification of potential therapeutic targets. In this mini-review, we will examine the therapeutic opportunities derived from genetically validated targets in FLD, including oligonucleotide-based therapies targeting PNPLA3 and HSD17B13 that are currently being evaluated in clinical trials for the treatment of NASH (non-alcoholic steatohepatitis).

From NAFLD to HCC: Advances in noninvasive diagnosis

Non-alcoholic fatty liver disease (NAFLD) has gradually become one of the major liver health problems in the world. The dynamic course of the disease goes through steatosis, inflammation, fibrosis, and carcinoma. Before progressing to carcinoma, timely and effective intervention will make the condition better, which highlights the importance of early diagnosis. With the further study of the biological mechanism in the pathogenesis and progression of NAFLD, some potential biomarkers have been discovered, and the possibility of their clinical application is gradually being discussed. At the same time, the progress of imaging technology and the emergence of new materials and methods also provide more possibilities for the diagnosis of NAFLD. This article reviews the diagnostic markers and advanced diagnostic methods of NAFLD in recent years.

Genetic risk of fatty liver disease and mortality in the general population: A Mendelian randomization study

BACKGROUND & AIMS

Fatty liver disease has been associated with higher all-cause as well as liver-related, ischemic heart disease (IHD)-related and extrahepatic cancer-related mortality in observational epidemiological studies. We tested the hypothesis that fatty liver disease is a causal risk factor for higher mortality.

METHODS

We genotyped seven genetic variants known to be associated with fatty liver disease (in PNPLA3, TM6SF2, HSD17B13, MTARC1, MBOAT7, GCKR, and GPAM) in 110 913 individuals from the Danish general population. Hepatic steatosis was measured by hepatic computed tomography in n = 6965. Using a Mendelian randomization framework, we tested whether genetically proxied hepatic steatosis and/or elevated plasma alanine transaminase (ALT) was associated with liver-related mortality.

RESULTS

During a median follow-up of 9.5 years, 16 119 individuals died. In observational analyses, baseline elevated plasma ALT was associated with higher all-cause (1.26-fold), liver-related (9-fold), and extrahepatic cancer-related (1.25-fold) mortality. In genetic analyses, the risk alleles in PNPLA3, TM6SF2, and HSD17B13 were individually associated with higher liver-related mortality. The largest effects were seen for the PNPLA3 and TM6SF2 risk alleles, for which homozygous carriers had 3-fold and 6-fold, respectively, higher liver-related mortality than non-carriers. None of the risk alleles, individually or combined into risk scores, were robustly associated with all-cause, IHD-related, or extrahepatic cancer-related mortality. In instrumental variable analyses, genetically proxied hepatic steatosis and higher plasma ALT were associated with liver-related mortality.

CONCLUSIONS

Human genetic data support that fatty liver disease is a causal driver of liver-related mortality.

Adverse effect of PNPLA3 p.I148M genetic variant on kidney function in middle-aged individuals with metabolic dysfunction

BACKGROUND

The PNPLA3 p.I148M variant is the main genetic determinant of nonalcoholic fatty liver disease, and PNPLA3 silencing is being evaluated to treat this liver condition. Data suggest that the p.I148M variant predisposes to kidney damage, but the relative contribution to kidney function, compared to overall genetic susceptibility, is not defined.

AIMS

We aimed to assess the effect of PNPLA3 p.I148M on the estimated glomerular filtration rate (eGFR) in individuals with metabolic dysfunction.

METHODS

We included 1144 middle-aged individuals from the Liver-Bible-2022 cohort. Glomerular filtration rate (eGFR) was estimated using the Chronic Kidney Disease Epidemiology Collaboration equation. The effect of PNPLA3 p.I148M on eGFR_CKD-EPI levels was tested under additive genetic models adjusted for clinical predictors, ethnicity and a polygenic risk score of chronic kidney disease (PRS-CKD). In a subset of 144 individuals, we examined the effect of PNPLA3 p.I148M on eGFR_CKD-EPI over a median follow-up of 17 months.

RESULTS

The p.I148M variant was associated with lower eGFR_CKD-EPI levels (-1.24 mL/min/1.73 m² per allele, 95% CI: -2.32 to -0.17; p = 0.023), independent of age, sex, height, waist circumference, systolic blood pressure, LDL-cholesterol, transaminases, fasting insulin, albuminuria, lipid-lowering drugs, ethnicity and PRS-CKD score. In the prospective evaluation, the p.I148M variant was independently associated with faster eGFR_CKD-EPI decline (ΔeGFR_CKD-EPI -3.57 mL/min/1.73 m² per allele, 95% CI: -6.94 to -0.21; p = 0.037).

CONCLUSIONS

We found a detrimental impact of the PNPLA3 p.I148M variant on eGFR_CKD-EPI levels in middle-aged individuals with metabolic dysfunction. This association was independent of established risk factors, ethnicity and genetic predisposition to CKD. PNPLA3 p.I148M silencing may protect against kidney damage progression in carriers.

Patatin-like phospholipase domain-containing 3 gene (PNPLA3) polymorphic (rs738409) single nucleotide polymorphisms and susceptibility to nonalcoholic fatty liver disease: A meta-analysis of twenty studies

BACKGROUND

To investigate the correlation between rs738409 polymorphism of patatin-like phospholipase domain-containing protein 3 (PNPLA3) gene (encoding I148m) and genetic susceptibility to nonalcoholic fatty liver disease (NAFLD).

METHODS

Web of Science, Embase, PubMed, Cochrane Library, China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform databases were subjected to study retrieving, from the earliest records to November 2022. International databases were searched using the key words (PNPLA3 gene or PNPLA3 polymorphism or patatin-like phospholipase domain-containing pro-tein3) and (nonalcoholic fatty liver disease or NAFLD or nonalcoholic steatohepatitis) and their possible combination. There was no limitation to language. Ethnicity and country restrictions were not applied. Hardy-Weinberg equilibrium about the genotype frequencies of rs738,409 polymorphism in group of controls was assessed using a chi-square goodness-of-fit test (P > .05). A chi-square-based Q test was applied to assess heterogeneity among studies. The random-effect model (DerSimonian-Laird method) was used when a probability value of P < .10, I2 > 50%. If not, the fixed-effect model (Mantel-Haenszel method) was adopted. The current meta-analysis was done by using STATA 16.0.

RESULTS

Twenty studies are selected for this meta-analysis, which includes totally 3240 patients in the treatment group and 5210 patients in the control group. These studies demonstrated a significant increased association between rs738,409 and NAFLD under 5 models: allelic contrast (odds ratio [OR] = 1.98, 95% confidence interval [CI] = 1.65-2.37, Pheterogeneity = 0.000, Z = 7.346, P = .000), homozygote comparison (OR = 3.59, 95% CI = 2.56-5.04, Pheterogeneity = 0.000, Z = 7.416, P = .000), heterozygote comparison (OR = 1.93, 95% CI = 1.63-2.30, Pheterogeneity = 0.002, Z = 7.507, P = .000), the dominant allele model (OR = 2.33, 95% CI = 1.89-2.88, Pheterogeneity = 0.000, Z = 7.856, P = .000), and the recessive allele model (OR = 2.56, 95% CI = 1.96-3.35, Pheterogeneity = 0.000, Z = 6.850, P = .000). Subgroup analysis shows that the rs738,409 polymorphism of PNPLA3 gene in Caucasians and those with a sample size of < 300 is significantly associated with the susceptibility to nonalcoholic fatty liver. Sensitivity analysis shows that the results of meta-analysis are stable.

CONCLUSION

PNPLA3 rs738,409 may play a significant role in increasing risk of NAFLD.

Challenges and opportunities in NASH drug development

Nonalcoholic fatty liver disease (NAFLD) and its more severe form, nonalcoholic steatohepatitis (NASH), represent a growing worldwide epidemic and a high unmet medical need, as no licensed drugs have been approved thus far. Currently, histopathological assessment of liver biopsies is mandatory as a primary endpoint for conditional drug approval. This requirement represents one of the main challenges in the field, as there is substantial variability in this invasive histopathological assessment, which leads to dramatically high screen-failure rates in clinical trials. Over the past decades, several non-invasive tests have been developed to correlate with liver histology and, eventually, outcomes to assess disease severity and longitudinal changes non-invasively. However, further data are needed to ensure their endorsement by regulatory authorities as alternatives to histological endpoints in phase 3 trials. This Review describes the challenges of drug development in NAFLD-NASH trials and potential mitigating strategies to move the field forward.

Advancing targeted protein degradation for metabolic diseases therapy

The development and application of traditional drugs represented by small molecule chemical drugs and biological agents, especially inhibitors, have become the mainstream drug development. In recent years, targeted protein degradation (TPD) technology has become one of the most promising methods to remove specific disease-related proteins using cell self-destruction mechanisms. Many different TPD strategies are emerging based on the ubiquitin-proteasome system (UPS) and the autophagy-lysosomal pathway (ALP), including but not limited to proteolysis-targeting chimeras (PROTAC), molecular glues (MG), lysosome targeting chimeras (LYTAC), chaperone-mediated autophagy (CMA)-targeting chimeras, autophagy-targeting chimera (AUTAC), autophagosome-tethering compound (ATTEC), and autophagy-targeting chimera (AUTOTAC). The advent of targeted degradation technology can change most protein targets in human cells from undruggable to druggable, greatly expanding the therapeutic prospect of refractory diseases such as metabolic syndrome. Here, we summarize the latest progress of major TPD technologies, especially in metabolic syndrome and look forward to providing new insights for drug discovery.

Risk factors in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease, with a global prevalence estimated at approximately 25%. NAFLD is also the leading cause of liver cirrhosis, hepatocellular carcinoma, and death. Additionally, the risk of cardiovascular disease increases with greater NAFLD severity. The liver- and cardiovascular disease-related mortality incident rate ratios among the NAFLD population were 0.77 and 4.79 per 1,000 person-years, respectively. We intend to discuss the risk factors associated with NAFLD in terms of development and progression. Obesity or higher body mass index is closely associated with NAFLD in a dose-dependent manner, but growing evidence suggests that central obesity plays a more important role in the development of NAFLD. Saturated fat and fructose have been reported to be closely related to NAFLD. Fructose intake promotes lipogenesis and impairs mitochondria fat oxidation. The presence of type 2 diabetes is the most powerful predictive risk factor for hepatic fibrosis in patients with NAFLD. Single nucleotide polymorphism is not only associated with the prevalence of NAFLD but also associated with increased liver disease mortality. Obstructive sleep apnea, intestinal dysbiosis, and sarcopenia are associated with the development of NAFLD.

Effect of common genetic variants on the risk of cirrhosis in non-alcoholic fatty liver disease during 20 years of follow-up

BACKGROUND AND AIMS

Several genotypes associate with a worse histopathological profile in patients with non-alcoholic fatty liver disease (NAFLD). Whether genotypes impact long-term outcomes is unclear. We investigated the importance of PNPLA3, TM6SF2, MBOAT7 and GCKR genotype for the development of severe outcomes in NAFLD.

METHOD

DNA samples were collected from 546 patients with NAFLD. Advanced fibrosis was diagnosed by liver biopsy or elastography. Non-alcoholic steatohepatitis (NASH) was histologically defined. Additionally, 5396 controls matched for age, sex and municipality were identified from population-based registers. Events of severe liver disease and all-cause mortality were collected from national registries. Hazard ratios (HRs) adjusted for age, sex, body mass index and type 2 diabetes were estimated with Cox regression.

RESULTS

In NAFLD, the G/G genotype of PNPLA3 was associated with a higher prevalence of NASH at baseline (odds ratio [OR] 3.67, 95% CI = 1.66-8.08), but not with advanced fibrosis (OR 1.81, 95% CI = 0.79-4.14). After up to 40 years of follow-up, the PNPLA3 G/G genotype was associated with a higher rate of severe liver disease (adjusted hazard ratio [aHR] 2.27, 95% CI = 1.15-4.47) compared with the C/C variant. NAFLD patients developed cirrhosis at a higher rate than controls (aHR 9.00, 95% CI = 6.85-11.83). The PNPLA3 G/G genotype accentuated this rate (aHR 23.32, 95% = CI 9.14-59.47). Overall mortality was not affected by any genetic variant.

CONCLUSION

The PNPLA3 G/G genotype is associated with an increased rate of cirrhosis in NAFLD. Our results suggest that assessment of the PNPLA3 genotype is of clinical relevance in patients with NAFLD to individualize monitoring and therapeutic strategies.

Current insights in molecular characterization of non-alcoholic fatty liver disease and treatment

There is a continuously rising incidence of non-alcoholic fatty liver disease (NAFLD) around the world, which parallels the increasing incidence of metabolic diseases. NAFLD is a range of liver conditions that contains simple non-alcoholic fatty liver and advanced non-alcoholic steatohepatitis. In serious cases, NAFLD may develop into cirrhosis or even liver cancer. NAFLD has an intense relationship with metabolic syndrome, type 2 diabetes mellitus. It is known that gut microbiota, and functional molecules such as adenosine monophosphate-activated protein kinase JNK, and peroxisome proliferator-activated receptors (PPARs) in progressing and treating NAFLD. Traditionally, the conventional and effective therapeutic strategy is lifestyle intervention. Nowadays, new medicines targeting specific molecules, such as farnesoid X receptor, PPARs, and GLP-1 receptor, have been discovered and shown beneficial effects on patients with NAFLD. In this article, we focus on the molecular mechanisms and therapeutic approaches to NAFLD.

Non-alcoholic fatty liver disease establishment and progression: genetics and epigenetics as relevant modulators of the pathology

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) results from metabolic dysfunctions that affect more than one-third of the world population. Over the last decades, scientific investigations have clarified many details on the pathology establishment and development; however, effective therapeutics approaches are still evasive. In addition, studies demonstrated that NAFLD establishment and progression are related to several etiologies. Recently, genetics and epigenetics backgrounds have emerged as relevant elements to the pathology onset, and, hence, deserve deep investigation to clarify molecular details on NAFLD signaling, which may be correlated with population behavior. Thus, to minimize the global problem, public health and public policies should take advantage of studies on NAFLD over the next following decades.

METHODS

In this context, we have performed a selective literature review focusing on biochemistry of lipid metabolism, genetics, epigenetics, and the ethnicity as strong elements that drive NAFLD establishment.

RESULTS

Considering the etiological agents that acts on NAFLD development and progression, the genetics and the epigenetics emerged as relevant factors. Genetics acts as a powerful element in the establishment and progression of the NAFLD. Over the last decades, details concerning genes and their polymorphisms, as well as epigenetics, have been considered relevant elements in the systems biology of diseases, and their effects on NAFLD should be considered in-depth, as well as the ethnicity, clarifying whether people are susceptible to liver diseases. Moreover, the endemicity and social problems of hepatic disfunction are far to be solved, which require a combined effort of various sectors of society.

CONCLUSION

Hence, the elements presented and discussed in this short review demonstrated their relevance to the physiological control of NAFLD, opening perspectives for research to develop new strategy to treat fatty liver diseases.

Shared Mechanisms between Cardiovascular Disease and NAFLD

The burden of nonalcoholic fatty liver disease (NAFLD) is rising globally. Cardiovascular disease is the leading cause of death in patients with NAFLD. Nearly half of individuals with NAFLD have coronary heart disease, and more than a third have carotid artery atherosclerosis. Individuals with NAFLD are at a substantially higher risk of fatal and nonfatal cardiovascular events. NAFLD and cardiovascular disease share multiple common disease mechanisms, such as systemic inflammation, insulin resistance, genetic risk variants, and gut microbial dysbiosis. In this review, we discuss the epidemiology of cardiovascular disease in NAFLD, and highlight common risk factors. In addition, we examine recent advances evaluating the shared disease mechanisms between NAFLD and cardiovascular disease. In conclusion, multidisciplinary collaborations are required to further our understanding of the complex relationship between NAFLD and cardiovascular disease and potentially identify therapeutic targets.