Ability of a Combined FIB4/miRNA181a Score to Predict Significant Liver Fibrosis in NAFLD Patients

Epigenetics in metabolic dysfunction-associated steatohepatitis

Metabolic dysfunction-associated steatohepatitis (MASH) is a complex disease involving genetics, environment, and lifestyle, with the potential to progress to liver fibrosis, cirrhosis, and even hepatocellular carcinoma (HCC). Although the pathogenesis of MASH is not fully clear, increasing evidence has indicated that epigenetics plays an important role in the genesis and progression of MASH, during which, as drastic changes in metabolites, epigenetics undergo drastic changes. Roles of chromatin structure, chromatin accessibility, DNA methylation, histone modification, and non-coding RNAs were considered as bridges of pathogenic factors and MASH. In this review, the research progress on the epigenetics of MASH was summarized, and indepth research and therapeutic strategies based on epigenetics is expected to bring new hope to MASH patients.

A class of MicroRNAs as diagnostic biomarkers and therapeutic strategies in non-alcoholic fatty liver disease: A review

MicroRNAs (miRNAs), small and noncoding RNAs that regulate gene expression through hybridization to messenger RNA, play a crucial role in the prevention or progression of non-alcoholic fatty liver disease (NAFLD). There is an urgent demand for the improvement of diagnostic tools and effective pharmacotherapies for the treatment of NAFLD, which can advance to cirrhosis and liver cancer. MiRNAs act as regulatory factors and noninvasive diagnostic agents for NAFLD, enabling the staging of the disorder, prognosis, and identification of pharmaco-therapeutic targets. NAFLD causes alterations in the expression patterns of hepatocyte miRNAs, with some specific miRNAs related to the upgrade from NAFLD to non-alcoholic steatohepatitis (NASH). These miRNAs can activate certain signaling cascade and exacerbate or improve NAFLD, additionally, act as hepatocellular signals or second messengers that transmit information between the liver and other systems. This study provides a comprehensive review of the most important miRNAs and their involvement in the pathophysiology and cellular signaling pathways related to NAFLD.

Interplays of liver fibrosis-associated microRNAs: Molecular mechanisms and implications in diagnosis and therapy

microRNAs (miRNAs) are a class of non-coding functional small RNA composed of 21-23 nucleotides, having multiple associations with liver fibrosis. Fibrosis-associated miRNAs are roughly classified into pro-fibrosis or anti-fibrosis types. The former is capable of activating hepatic stellate cells (HSCs) by modulating pro-fibrotic signaling pathways, mainly including TGF-β/SMAD, WNT/β-catenin, and Hedgehog; the latter is responsible for maintenance of the quiescent phenotype of normal HSCs, phenotypic reversion of activated HSCs (aHSCs), inhibition of HSCs proliferation and suppression of the extracellular matrix-associated gene expression. Moreover, several miRNAs are involved in regulation of liver fibrosis via alternative mechanisms, such as interacting between hepatocytes and other liver cells via exosomes and increasing autophagy of aHSCs. Thus, understanding the role of these miRNAs may provide new avenues for the development of novel interventions against hepatic fibrosis.

MicroRNAs as Biomarkers and Therapeutic Targets for Nonalcoholic Fatty Liver Disease: A Narrative Review

PURPOSE

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the world. However, biomarkers for NAFLD diagnosis and liver-specific drugs for treatment are lacking. This article reviews the possibility of circulating miRNAs in the diagnosis and treatment of NAFLD diseases and focuses on several well-studied miRNAs to provide preclinical data for subsequent related studies.

METHODS

Related articles were identified through searches of the PubMed database for literature published from 2010 to December 2022. Search terms included NAFLD, microRNA, biomarker, diagnosis, and therapy.

FINDINGS

Current research data indicate that some key circulating miRNAs may be used as diagnostic biomarkers of NAFLD and the combination of several miRNAs improves diagnostic performance. In addition, some preclinical trials using cell and mouse models provide a basis for some miRNAs as potential therapeutic targets.

IMPLICATIONS

Current evidence suggests that circulating miRNAs are potential noninvasive biomarkers for clinical diagnosis of NAFLD, which needs to be validated in more heterogeneous and larger cohorts. In addition, several miRNAs regulate multiple downstream pathways related to the pathophysiology of NAFLD in a cell- and tissue-specific manner, making them attractive drug therapeutic targets for NAFLD. However, more preclinical and clinical trials are needed for these miRNAs to become therapeutic targets of NAFLD.

Role of non-coding RNAs on liver metabolism and NAFLD pathogenesis

Obesity and type 2 diabetes are major contributors to the growing prevalence of non-alcoholic fatty liver disease (NAFLD), a chronic liver condition characterized by the accumulation of fat in individuals without a significant amount of alcohol intake. The NAFLD spectrum ranges from simple steatosis (early stages, known as NAFL) to non-alcoholic steatohepatitis, which can progress to fibrosis and cirrhosis or hepatocellular carcinoma. Obesity, type 2 diabetes and NAFLD are strongly associated with insulin resistance. In the liver, insulin resistance increases hepatic glucose output, lipogenesis and very-low-density lipoprotein secretion, leading to a combination of hyperglycemia and hypertriglyceridemia. Aberrant gene expression is a hallmark of insulin resistance. Non-coding RNAs (ncRNAs) have emerged as prominent regulators of gene expression that operate at the transcriptional, post-transcriptional and post-translational levels. In the last couple of decades, a wealth of studies have provided evidence that most processes of liver metabolism are orchestrated by ncRNAs. This review focuses on the role of microRNAs, long non-coding RNAs and circular RNAs as coordinators of hepatic function, as well as the current understanding on how their dysregulation contributes to abnormal metabolism and pathophysiology in animal models of insulin resistance and NAFLD. Moreover, ncRNAs are emerging as useful biomarkers that may be able to discriminate between the different stages of NAFLD. The potential of ncRNAs as therapeutic drugs for NAFLD treatment and as biomarkers is discussed.

NAFLD: From Mechanisms to Therapeutic Approaches

Nonalcoholic fatty liver disease (NAFLD) now represents the most frequent chronic liver disease worldwide [...]