MAFLD vs NAFLD: Let the contest begin!

Poor accuracy and sustainability of the first-step FIB4 EASL pathway for stratifying steatotic liver disease risk in the general population

BACKGROUND AND AIMS

The European Association for the Study of the Liver introduced a clinical pathway (EASL CP) for screening significant/advanced fibrosis in people at risk of steatotic liver disease (SLD). We assessed the performance of the first-step FIB4 EASL CP in the general population across different SLD risk groups (MASLD, Met-ALD and ALD) and various age classes.

METHODS

We analysed a total of 3372 individuals at risk of SLD from the 2017-2018 National Health and Nutrition Examination Survey (NHANES17-18), projected to 152.3 million U.S. adults, 300,329 from the UK Biobank (UKBB) and 57,644 from the Biobank Japan (BBJ). We assessed liver stiffness measurement (LSM) ≥8 kPa and liver-related events occurring within 3 and 10 years (3/10 year-LREs) as outcomes. We defined MASLD, MetALD, and ALD according to recent international recommendations.

RESULTS

FIB4 sensitivity for LSM ≥ 8 kPa was low (27.7%), but it ranged approximately 80%-90% for 3-year LREs. Using FIB4, 22%-57% of subjects across the three cohorts were identified as candidates for vibration-controlled transient elastography (VCTE), which was mostly avoidable (positive predictive value of FIB4 ≥ 1.3 for LSM ≥ 8 kPa ranging 9.5%-13% across different SLD categories). Sensitivity for LSM ≥ 8 kPa and LREs increased with increasing alcohol intake (ALD>MetALD>MASLD) and age classes. For individuals aged ≥65 years, using the recommended age-adjusted FIB4 cut-off (≥2) substantially reduced sensitivity for LSM ≥ 8 kPa and LREs.

CONCLUSIONS

The first-step FIB4 EASL CP is poorly accurate and feasible for individuals at risk of SLD in the general population. It is crucial to enhance the screening strategy with a first-step approach able to reduce unnecessary VCTEs and optimise their yield.

Metabolic disease and the liver: A review

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common liver disease worldwide, with an estimated prevalence of 31% in Latin America. The presence of metabolic comorbidities coexisting with liver disease varies substantially among populations. It is acknowledged that obesity is boosting the type 2 diabetes mellitus "epidemic," and both conditions are significant contributors to the increasing number of patients with MASLD. Non-alcoholic steatohepatitis represents a condition of chronic liver inflammation and is considered the most severe form of MASLD. MASLD diagnosis is based on the presence of steatosis, noninvasive scores and altered liver tests. Noninvasive scores of liver fibrosis, such as serum biomarkers, which should be used in primary care to rule out advanced fibrosis, are simple, inexpensive, and widely available. Currently, guidelines from international hepatology societies recommend using noninvasive strategies to simplify case finding and management of high-risk patients with MASLD in clinical practice. Unfortunately, there is no definite pharmacological treatment for the condition. Creating public health policies to treat patients with risk factors for MASLD prevention is essential.

IL32 downregulation lowers triglycerides and type I collagen in di-lineage human primary liver organoids

Steatotic liver disease (SLD) prevails as the most common chronic liver disease yet lack approved treatments due to incomplete understanding of pathogenesis. Recently, elevated hepatic and circulating interleukin 32 (IL-32) levels were found in individuals with severe SLD. However, the mechanistic link between IL-32 and intracellular triglyceride metabolism remains to be elucidated. We demonstrate in vitro that incubation with IL-32β protein leads to an increase in intracellular triglyceride synthesis, while downregulation of IL32 by small interfering RNA leads to lower triglyceride synthesis and secretion in organoids from human primary hepatocytes. This reduction requires the upregulation of Phospholipase A2 group IIA (PLA2G2A). Furthermore, downregulation of IL32 results in lower intracellular type I collagen levels in di-lineage human primary hepatic organoids. Finally, we identify a genetic variant of IL32 (rs76580947) associated with lower circulating IL-32 and protection against SLD measured by non-invasive tests. These data suggest that IL32 downregulation may be beneficial against SLD.

Association between cataract and fatty liver diseases from a nationwide cross-sectional study in South Korea

This study examined the link between fatty liver disease (FLD) and cataracts, as previous research has suggested that FLD may contribute to metabolic syndrome, systemic inflammation, and potentially cataracts. We studied a nationwide cross-sectional cohort of the Fifth Korean National Health and Nutrition Examination Survey 2010-2011. FLD was defined as nonalcoholic FLD (NAFLD) and metabolic dysfunction-associated FLD (MAFLD). Multinomial logistic regression was utilized to investigate the relationship between cataracts and FLD after adjustment for potential confounders. Participants with cataracts had higher liver fibrosis scores, including the NAFLD fibrosis score (NFS; P < 0.001), fibrosis-4 index (FIB4; P < 0.001), and fatty liver index (FLI; P = 0.001). NAFLD was not associated with a higher odds ratio (OR) for cataracts in the fully adjusted model (OR = 1.23, P = 0.058). MAFLD was significantly associated with a higher OR (OR = 1.34, P = 0.006). After adjusting for all factors, the severity of FLD was linked to an increased risk of cataracts, with significant linear trends (P values for linear trends of NFS, FIB4, and FLI < 0.05). After adjusting for well-known cataract risk factors, MAFLD was significantly associated with cataracts. Our analysis suggests that FLD may serve as an independent risk factor for cataracts.

Nonalcoholic Fatty Liver Disease vs Metabolic-associated Fatty Liver Disease vs Metabolic Dysfunction-associated Steatotic Liver Disease: What's in the Name?

How to cite this article: Singh SP, Sudhamshu KC, Anirvan P, et al. Nonalcoholic Fatty Liver Disease vs Metabolic-associated Fatty Liver Disease vs Metabolic Dysfunction-associated Steatotic Liver Disease: What's in the Name? Euroasian J Hepato-Gastroenterol 2024;14(1):1-4.

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).

Metabolic dysfunction-associated fatty liver disease in people living with HIV

The prevalence of metabolic risk factors and non-alcoholic fatty liver disease (NAFLD) is high among people living with HIV (PLWH). Data on the recently proposed definition of metabolic dysfunction-associated fatty liver disease (MAFLD) in PLWH receiving antiretroviral therapy (ART) remains unknown. A total of 282 PLWH were included in this cross-sectional cohort study. Vibration-controlled transient elastography (VCTE) was used to assess hepatic steatosis and fibrosis. MAFLD and its subgroups (overweight/obese, lean/normal weight, and type 2 diabetes) were defined according to a recently published international consensus statement. The majority of this cohort was male (n = 198, 70.2%), and the median age was 51.5 years. The median BMI was 25 kg/m², and obesity was prevalent in 16.2% (n = 44). A total of 207 (73.4%) PLWH were classified as non-MAFLD while 75 (26.6%) qualified as MAFLD. The median CAP in the MAFLD group was 320 dB/m. PLWH with MAFLD showed a higher median LSM (p < 0.008) and were older (p < 0.005) compared to the non-MAFLD group. Overall, the metabolic risk profile was comparable between MAFLD and NAFLD. The majority of PLWH and MAFLD were overweight or obese (n = 58, 77.3%). The highest median LSM values were observed in the subgroup with MAFLD and type 2 diabetes. HIV-related parameters did not differ between non-MAFLD and MAFLD. The prevalence of MAFLD in PLWH is high and comparable to NAFLD. PLWH may be characterized according to the novel MAFLD criteria and its subgroups to identify patients at risk for chronic liver disease.

Outcomes of fatty liver disease with and without metabolic comorbidities and risk factors for mortality

Background and Aim

As the clinical course of metabolic-associated fatty liver disease (MAFLD) is unclear, we compared the clinical courses of MAFLD and non-alcoholic FLD (NAFLD).

Methods

Asian FLD patients (n = 987) from 1991 to 2021 (biopsy-proven in 939) were enrolled. The patients were divided into NAFLD (N-alone, n = 92), both MAFLD and N (M&N, n = 785), and M-alone (n = 90) groups. Clinical features, complications, and survival rates were compared among the three groups. Risk factors of mortality were subjected to Cox regression analysis.

Results

The N-alone group patients were significantly younger (N alone, M&N, and M alone: 50, 53, and 57 years, respectively), more frequently male (54.3%, 52.6%, and 37.8%), and had a low body mass index (BMI, 23.1, 27.1, and 26.7 kg/m²) and FIB-4 index (1.20, 1.46, and 2.10). Hypopituitarism (5.4%) and hypothyroidism (7.6%) were significantly observed in the N-alone group. Hepatocellular carcinoma (HCC) developed in 0.0%, 4.2%, and 3.5% of the cases, and extrahepatic malignancies in 6.8%, 8.4%, and 4.7% of the cases, respectively, with no significant differences. The cardiovascular event rate was significantly higher in the M-alone group (1, 37, and 11 cases, P < 0.01). Survival rates were similar among the three groups. Risk factors for mortality were age and BMI in the N-alone group; age, HCC, alanine transaminase, and FIB-4 in the M&N group; and FIB-4 in the M-alone group.

Conclusion

Different risk factors for mortality may exist among the FLD groups.

NAFLD, MAFLD, and beyond: one or several acronyms for better comprehension and patient care

The term non-alcoholic fatty liver disease (NAFLD) has rapidly become the most common type of chronic liver disease. NAFLD points to excessive hepatic fat storage and no evidence of secondary hepatic fat accumulation in patients with "no or little alcohol consumption". Both the etiology and pathogenesis of NAFLD are largely unknown, and a definitive therapy is lacking. Since NAFLD is very often and closely associated with metabolic dysfunctions, a consensus process is ongoing to shift the acronym NAFLD to MAFLD, i.e., metabolic-associated fatty liver disease. The change in terminology is likely to improve the classification of affected individuals, the disease awareness, the comprehension of the terminology and pathophysiological aspects involved, and the choice of more personalized therapeutic approaches while avoiding the intrinsic stigmatization due to the term "non-alcoholic". Even more recently, other sub-classifications have been proposed to concentrate the heterogeneous causes of fatty liver disease under one umbrella. While awaiting additional validation studies in this field, we discuss the main reasons underlying this important shift of paradigm.

Metabolic-Dysfunction-Associated Fatty Liver Disease and Gut Microbiota: From Fatty Liver to Dysmetabolic Syndrome

Metabolic-dysfunction-associated fatty liver disease (MAFLD) is the recent nomenclature designation that associates the condition of non-alcoholic fatty liver disease (NAFLD) with metabolic dysfunction. Its diagnosis has been debated in the recent period and is generally associated with a diagnosis of steatosis and at least one pathologic condition among overweight/obesity, type 2 diabetes mellitus, and metabolic dysregulation. Its pathogenesis is defined by a “multiple-hit” model and is associated with alteration or dysbiosis of the gut microbiota. The pathogenic role of dysbiosis of the gut microbiota has been investigated in many diseases, including obesity, type 2 diabetes mellitus, and NAFLD. However, only a few works correlate it with MAFLD, although common pathogenetic links to these diseases are suspected. This review underlines the most recurrent changes in the gut microbiota of patients with MAFLD, while also evidencing possible pathogenetic links.

Nonalcoholic fatty liver disease from a primary care perspective

Nonalcoholic fatty liver disease (NAFLD) affects up to one-third of the US population. Approximately one-fifth of patients with NAFLD have nonalcoholic steatohepatitis (NASH), characterized by hepatocyte damage and inflammation with or without fibrosis. NASH leads to greater risk of liver-related complications and liver-related mortality, with the poorest outcomes seen in patients with advanced fibrosis. NASH is also associated with other metabolic comorbidities and conveys an increased risk of adverse cardiovascular outcomes and extrahepatic cancers. Despite its high prevalence, NAFLD is frequently underdiagnosed. This is a significant concern, given that early diagnosis of NAFLD is a key step in preventing progression to NASH. In this review, we describe the clinical impact of NASH from the perspective of both the clinician and the patient. In addition, we provide practical guidance on the diagnosis and management of NASH for primary care providers, who play a pivotal role in the frontline care of patients with NASH, and we use case studies to illustrate real-world scenarios encountered in the primary care setting.

Nutritional intervention in the management of non-alcoholic fatty liver disease

Lifestyle modification is the primary intervention to control NAFLD progression, but despite evidence-based effectiveness it is difficult to distinguish the benefits of nutrition from physical activity and the optimal diet composition is not established. Macronutrients as saturated fatty acids, sugars and animal proteins are harmful in NAFLD and the Mediterranean Diet reducing sugar, red meat and refined carbohydrates and increasing unsaturated-fatty-acids was reported to be beneficial. However one size cannot fit all since NAFLD is a multifaceted syndrome encompassing many diseases of unknown etiologies, different clinical severity and outcomes. Studies of the intestinal metagenome, provided new insights into the physio-pathological interplay between intestinal microbiota and NAFLD. How much the microbiota heterogeneity can influence response to diet remains unknown. New knowledge indicates that AI guided personalized nutrition based on clinic-pathologic and genetic data combined with pre/post nutritional intervention gut metagenomics/metabolomics will be part of the future management of NAFLD.

Bergamot Polyphenol Extract Reduces Hepatocyte Neutral Fat by Increasing Beta-Oxidation

Background: Bergamot polyphenolic fraction (PF) extract exerts a beneficial against liver steatosis. However, the fundamental processes underlying this beneficial effect of bergamot PF remain elusive. In this work, we examined the effect of bergamot PF extract on 2D and 3D hepatocyte cultures. Material and Methods: We evaluated the effect of bergamot PF in 2D and 3D cultures from rat, human hepatoma cells, and human primary hepatocytes. Results: In 2D cell culture, we demonstrated that incubation with bergamot PF decreases intracellular lipid content and is associated with an increase in expression levels of ß-oxidation genes (Acox1, Pparα, and Ucp2) and lipophagy (Atg7). Moreover, we confirm this effect on 3D spheroids and organoids. Conclusion: Incubation with bergamot PF reduces intracellular lipid neutral fat potentially by increasing intracellular pathways related to beta-oxidation.

Noncoding RNAs in liver physiology and metabolic diseases

The liver holds central roles in detoxification, energy metabolism and whole-body homeostasis but can develop malignant phenotypes when being chronically overwhelmed with fatty acids and glucose. The global rise of metabolic-associated fatty liver disease (MAFLD) is already affecting a quarter of the global population. Pharmaceutical treatment options against different stages of MAFLD do not yet exist and several clinical trials against hepatic transcription factors and other proteins have failed. However, emerging roles of noncoding RNAs, including long (lncRNA) and short noncoding RNAs (sRNA), in various cellular processes pose exciting new avenues for treatment interventions. Actions of noncoding RNAs mostly rely on interactions with proteins, whereby the noncoding RNA fine-tunes protein function in a process termed riboregulation. The developmental stage-, disease stage- and cell type-specific nature of noncoding RNAs harbors enormous potential to precisely target certain cellular pathways in a spatio-temporally defined manner. Proteins interacting with RNAs can be categorized into canonical or non-canonical RNA binding proteins (RBPs) depending on the existence of classical RNA binding domains. Both, RNA- and RBP-centric methods have generated new knowledge of the RNA-RBP interface and added an additional regulatory layer. In this review, we summarize recent advances of how of RBP-lncRNA interactions and various sRNAs shape cellular physiology and the development of liver diseases such as MAFLD and hepatocellular carcinoma.

Insight into Potential Interactions of Thyroid Hormones, Sex Hormones and Their Stimulating Hormones in the Development of Non-Alcoholic Fatty Liver Disease

Non-Alcoholic Fatty Liver Disease (NAFLD) is a common manifestation of metabolic syndrome. In addition to lifestyle, endocrine hormones play a role in the dysregulation of hepatic metabolism. The most common endocrine hormones contributing to metabolic syndrome are alterations in the levels of thyroid hormones (THs, predominantly in subclinical hypothyroidism) and of sex hormones (in menopause). These hormonal changes influence hepatic lipid and glucose metabolism and may increase hepatic fat accumulation. This review compares the effects of sex hormones, THs and the respective stimulating hormones, Thyroid-Stimulating Hormone (TSH) and Follicle-Stimulating Hormone (FSH), on the development of hepatosteatosis. TSH and FSH may be more relevant to the dysregulation of hepatic metabolism than the peripheral hormones because metabolic changes were identified when only levels of the stimulating hormones were abnormal and the peripheral hormones were still in the reference range. Increased TSH and FSH levels appear to have additive effects on the development of NAFLD and to act independently from each other.

A minority of somatically mutated genes in pre-existing fatty liver disease have prognostic importance in the development of NAFLD

BACKGROUND

Understanding the genetics of liver disease has the potential to facilitate clinical risk stratification. We recently identified acquired somatic mutations in six genes and one lncRNA in pre-existing fatty liver disease. We hypothesised that germline variation in these genes might be associated with the risk of developing steatosis and contribute to the prediction of disease severity.

METHODS

Genome-wide association study (GWAS) summary statistics were extracted from seven studies (>1.7 million participants) for variants near ACVR2A, ALB, CIDEB, FOXO1, GPAM, NEAT1 and TNRC6B for: aminotransferases, liver fat, HbA1c, diagnosis of NAFLD, ARLD and cirrhosis. Findings were replicated using GWAS data from multiple independent cohorts. A phenome-wide association study was performed to examine for related metabolic traits, using both common and rare variants, including gene-burden testing.

RESULTS

There was no evidence of association between rare germline variants or SNPs near five genes (ACVR2A, ALB, CIDEB, FOXO1 and TNRC6B) and risk or severity of liver disease. Variants in GPAM (proxies for p.Ile43Val) were associated with liver fat (p = 3.6 × 10-13 ), ALT (p = 2.8 × 10-39 ) and serum lipid concentrations. Variants in NEAT1 demonstrated borderline significant associations with ALT (p = 1.9 × 10-11 ) and HbA1c, but not with liver fat, as well as influencing waist-to-hip ratio, adjusted for BMI.

CONCLUSIONS

Despite the acquisition of somatic mutations at these loci during progressive fatty liver disease, we did not find associations between germline variation and markers of liver disease, except in GPAM. In the future, larger sample sizes may identify associations. Currently, germline polygenic risk scores will not capture data from genes affected by somatic mutations.

MAFLD and CKD: An Updated Narrative Review

Accumulating evidence now indicates that non-alcoholic fatty liver disease (NAFLD), which is the most common chronic liver disease observed in clinical practice worldwide, is independently associated with an increased risk of incident chronic kidney disease (CKD). Given that NAFLD is linked to insulin resistance, obesity and type 2 diabetes mellitus, an international panel of experts have recently proposed a name change from NAFLD to metabolic associated fatty liver disease (MAFLD). Since the diagnostic criteria for NAFLD and MAFLD are different, observational studies assessing the potential concordance (or even superiority) of MAFLD, compared with NAFLD, in detecting patients at increased risk of hepatic and extra-hepatic complications (including CKD) are required. Hence, in the last two years, some observational studies have investigated the potential relationship between MAFLD and CKD. The result is that, at present, evidence regarding the concordance or even superiority of MAFLD, compared with NAFLD, in detecting patients at higher risk of CKD is still preliminary, although some data indicate that MAFLD identifies patients with CKD as accurately as NAFLD. In this narrative review, we will discuss: (a) the epidemiological evidence assessing the association between NAFLD and risk of incident CKD, (b) the epidemiological data investigating the association between MAFLD and risk of CKD and (c) the biological mechanisms underlying the association between NAFLD/MAFLD and CKD.

The Health Impact of MAFLD, a Novel Disease Cluster of NAFLD, Is Amplified by the Integrated Effect of Fatty Liver Disease-Related Genetic Variants

BACKGROUND & AIMS

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a newly proposed disease category that derived from non-alcoholic fatty liver disease. The impact of MAFLD on health events has not been investigated.

METHODS

UK Biobank participants were diagnosed for whether MAFLD presented at baseline. Five genetic variants (PNPLA3 rs738409 C/G, TM6SF2 rs58542926 C/T, GCKR rs1260326 T/C, MBOAT7 rs641738 C/T, and HSD17B13 rs72613567 T/TA) were integrated into a genetic risk score (GRS). Cox proportional hazard model was used to examine the association of MAFLD with incident diseases.

RESULTS

A total of 160 979 (38.0%, 95% confidence interval [CI] 37.9%, 38.2%) participants out of 423 252 were diagnosed as MAFLD. Compared with participants without MAFLD, MAFLD cases had multivariate adjusted hazard ratio (HR) for liver cancer of 1.59 (95% CI, 1.28, 1.98), cirrhosis of 2.77 (2.29, 3.36), other liver diseases of 2.09 (1.95, 2.24), cardiovascular diseases of 1.39 (1.34, 1.44), renal diseases of 1.56 (1.48, 1.65), and cancers of 1.07 (1.05, 1.10). The impact of MAFLD, especially on hepatic events, was amplified by high GRS, of which the genetic variations in PNPLA3, TM6SF2, and MBOAT7 play the principal roles. MAFLD case with normal body weight is also associated with an increased risk of hepatic outcomes, but the genetic factor seems do not influence the risk in this subpopulation.

CONCLUSIONS

MAFLD is independently associated with an increased risk of both intrahepatic and extrahepatic events. Fatty liver disease related genetic variants amplify the effect of MAFLD on disease outcomes.

Long-term prognosis of patients with metabolic (dysfunction)-associated fatty liver disease by non-invasive methods

BACKGROUND

Non-invasive assessment of fibrosis is predictive of the prognosis of non-alcoholic and alcoholic fatty liver disease but this has not been demonstrated in metabolic (dysfunction)-associated fatty liver disease (MAFLD).

AIMS

We assessed the prognosis of non-invasive methods in patients with MAFLD.

METHODS

All consecutive patients with MAFLD, with liver stiffness measurements, FIB-4 (Fibrosis-4), and LIVERFASt were included in this cohort study. The primary endpoint was analysed by the Kaplan-Meier method and secondary endpoints were estimated by Gray test or logistic regression. Factors independently associated with overall mortality and morbidity were identified by a multivariate Cox model. The prognostic performance of non-invasive methods for prediction of mortality was evaluated by Harrell's C-index and for morbidity by area under the receiver operating characteristics curve (AUC).

RESULTS

A total of 1239 patients with MAFLD were analysed (median age 56 years, male 56.5%, median body mass index 31 kg/m² and obesity 59%). The median follow-up was 62 months [42-91 months] and 73 (5.8%) subjects died. Baseline results of non-invasive methods were correlated with overall and liver-related mortalities (P < 0.001), and with all-cause and liver-related outcomes (P < 0.001). A predictive model (composed of clinical parameters and liver stiffness measurement, FIB-4 or LIVERFASt) was an excellent predictor of overall and liver-related mortalities (C-index 0.8-0.9), and a good predictor of overall and liver-related morbidities (AUC 0.72-0.74).

CONCLUSION

Baseline liver stiffness measurement, FIB-4 and LIVERFASt can predict global and liver-related mortality and morbidity in patients with MAFLD and could be prognosis endpoints in clinical trials.

Matching mouse models to specific human liver disease states by comparative functional genomics of mouse and human datasets

Omics has broadened our view of transcriptional and gene regulatory networks of multifactorial diseases, such as metabolism associated liver disease and its advanced stages including hepatocellular carcinoma. Identifying liver disease biomarkers and potential treatment targets makes use of experimental models, e.g. genetically engineered mice, which show molecular features of human pathologies but are experimentally tractable. We compared gene expression profiling data from human to our studies on transgenic mice with hepatocyte deletion of Cyp51 from cholesterol synthesis with the aim of identifying the human liver disease state best matched by the Cyp51 knockout model. Gene Expression Omnibus was used to identify relevant human datasets. We identified enriched and deregulated genes, pathways and transcription factors of mouse and human disease samples. Analysis showed a closer match of the Cyp51 knockout to the female patient samples. Importantly, CYP51 was depleted in both mouse and female human data. Among the enriched genes were the oxysterol-binding protein-related protein 3 (OSBPL3), which was enriched in all datasets, and the collagen gene COL1A2, which was enriched in both the mouse and one human dataset. KEGG and Reactome analyses revealed the most enriched pathway to be ECM-receptor interaction. Numerous transcription factors were differentially expressed in mice of both sexes and in the human female dataset, while depleted HNF4α and RXRα:PPARα-isoform1 were a hallmark in all cases. Our analysis exposed novel potential biomarkers, which may provide new avenues towards more personalized approaches and different targets in females and males. The analysis was only possible because of availability of open data resources and tools and broadly consistent annotation.

The pathologic relevance of metabolic criteria in patients with biopsy-proven nonalcoholic fatty liver disease and metabolic dysfunction associated fatty liver disease: A multicenter cross-sectional study in China

BACKGROUND

This study aimed to assess the association between metabolic syndrome (MetS) and severity of nonalcoholic fatty liver disease (NAFLD), and to discuss the pathological relevance of the diagnostic criteria in metabolic (dysfunction) associated fatty liver disease (MAFLD).

METHODS

This was a multicenter, cross-sectional study. Patients with NAFLD confirmed by liver biopsy were enrolled between July 2016 and December 2018 from 14 centers across the mainland of China. Anthropometric and metabolic parameters were collected to assess the pathological relevance.

RESULTS

Of 246 enrolled patients with NAFLD, 150 (61.0%) had the comorbidity of MetS. With the increase of metabolic components, the proportions of nonalcoholic steatohepatitis (NASH) and significant fibrosis were notably increased. The comorbid three metabolic components significantly increased the proportion of NASH, and further increase of metabolic components did not increase the proportion of NASH. However, the increase of metabolic components was parallel to the increase of the proportion of liver fibrosis. Among the 246 patients, 239 (97.2%) met the diagnostic criteria of MAFLD. Although non-MAFLD patients had less NASH, they present with similar proportion of significant fibrosis and cirrhosis. In the diagnostic criteria of MAFLD, BMI ≥ 23 kg/m2 was related to NASH (Mantel-Haenszel Common Estimate OR: 2.975; 95% CI: 1.037-8.538; P = 0.043), and T2DM was related to significant fibrosis (Mantel-Haenszel Common Estimate OR: 2.531; 95% CI: 1.388-4.613; P = 0.002). The homeostasis model assessment of insulin resistance (HOMA-IR) ≥ 2.5 was the most significant factor for NASH (OR: 4.100; 95% CI: 1.772-9.487; P = 0.001) and significant factor for liver fibrosis (OR: 2.947; 95% CI: 1.398-6.210; P = 0.004) after the adjustments of the BMI and diabetes.

CONCLUSIONS

Metabolic dysregulations are important risk factors in NAFLD progression. The insulin resistance status may play a predominant role in the progression in MAFLD patients.

Perspectives on Precision Medicine Approaches to NAFLD Diagnosis and Management

Precision medicine defines the attempt to identify the most effective approaches for specific subsets of patients based on their genetic background, clinical features, and environmental factors. Nonalcoholic fatty liver disease (NAFLD) encompasses the alcohol-like spectrum of liver disorders (steatosis, steatohepatitis with/without fibrosis, and cirrhosis and hepatocellular carcinoma) in the nonalcoholic patient. Recently, disease renaming to MAFLD [metabolic (dysfunction)-associated fatty liver disease] and positive criteria for diagnosis have been proposed. This review article is specifically devoted to envisaging some clues that may be useful to implementing a precision medicine-oriented approach in research and clinical practice. To this end, we focus on how sex and reproductive status, genetics, intestinal microbiota diversity, endocrine and metabolic status, as well as physical activity may interact in determining NAFLD/MAFLD heterogeneity. All these factors should be considered in the individual patient with the aim of implementing an individualized therapeutic plan. The impact of considering NAFLD heterogeneity on the development of targeted therapies for NAFLD subgroups is also extensively discussed.

A single-letter change in an acronym: signals, reasons, promises, challenges, and steps ahead for moving from NAFLD to MAFLD

Introduction: We are currently at the dawn of a revolution in the field of fatty liver diseases. Recently, a consensus recommended 'metabolic (dysfunction) associated fatty liver disease' (MAFLD) as a more appropriate name to describe fatty liver disease associated with metabolic dysfunction, ultimately suggesting that the old acronym nonalcoholic fatty liver disease (NAFLD) should be abandoned.Areas covered: In this viewpoint, we discuss the reasons and relevance of this semantic modification through five different conceptual domains, i.e., 1) signals, 2) reasons, 2) promises, 4) challenges and 5) steps ahead.Expert opinion: The road ahead will not be traveled without major challenges. Further research to evaluate the positive and negative impacts of the nomenclature change is warranted. However, this modification should encourage increased disease awareness among policymakers and stimulate public and private investments leading to more effective therapy development.

Genetic predisposition similarities between NASH and ASH: Identification of new therapeutic targets

Fatty liver disease can be triggered by a combination of excess alcohol, dysmetabolism and other environmental cues, which can lead to steatohepatitis and can evolve to acute/chronic liver failure and hepatocellular carcinoma, especially in the presence of shared inherited determinants. The recent identification of the genetic causes of steatohepatitis is revealing new avenues for more effective risk stratification. Discovery of the mechanisms underpinning the detrimental effect of causal mutations has led to some breakthroughs in the comprehension of the pathophysiology of steatohepatitis. Thanks to this approach, hepatocellular fat accumulation, altered lipid droplet remodelling and lipotoxicity have now taken centre stage, while the role of adiposity and gut-liver axis alterations have been independently validated. This process could ignite a virtuous research cycle that, starting from human genomics, through omics approaches, molecular genetics and disease models, may lead to the development of new therapeutics targeted to patients at higher risk. Herein, we also review how this knowledge has been applied to: a) the study of the main PNPLA3 I148M risk variant, up to the stage of the first in-human therapeutic trials; b) highlight a role of MBOAT7 downregulation and lysophosphatidyl-inositol in steatohepatitis; c) identify IL-32 as a candidate mediator linking lipotoxicity to inflammation and liver disease. Although this precision medicine drug discovery pipeline is mainly being applied to non-alcoholic steatohepatitis, there is hope that successful products could be repurposed to treat alcohol-related liver disease as well.

The NAFLD-MAFLD debate: Eminence vs evidence

Debates are inevitable in science and could be a powerful tool for addressing controversial topics as it promotes critical thinking and inspires individuals to consider alternate viewpoints. However, debates can help only to identify the issues that need to be clarified to address this question, but it can never help resolve the controversy itself. In the era of evidence-based medicine, the need for an evidence-based debate is mandatory. Polarising opinions and major debate have recently arisen in hepatology on the nomenclature and diagnostic criteria for fatty liver disease associated with metabolic dysfunction (non alcoholic fatty liver disease [NAFLD]-metabolic (dysfunction) associated fatty liver disease [MAFLD] debate). The aim of this viewpoint is to suggest a way to settle the debate through evidence. Descriptive review using PubMed to identify literature on the evidence and eminence-based medicine and studies comparing MAFLD and NAFLD criteria. The emerging studies comparing the performance of diagnostic criteria of NAFLD and MAFLD represent the dawn of a new era for reframing the ongoing debate by acquisition of the mandatory evidence that will both resolve the debate and lead to novel avenues of research. In conclusion, the time has come to hold debate and focus on gathering and building the evidence to settle it. It does not matter who wins the debate and once there is robust evidence, we should all follow it wherever it leads.