Caveolin‑1 is critical for hepatic iron storage capacity in the development of nonalcoholic fatty liver disease

Background:Nonalcoholic fatty liver disease(NAFLD)is associated with disordered lipid and iron metabolism.Our previous study has substantiated the pivotal role of Caveolin-1(Cav-1)in protecting hepatocytes and mediating iron metabolism in the liver.This study aimed to explore the specific mechanisms underlying the regulation of iron metabolism by Cav-1 in NAFLD.Methods:Hepatocyte-specific Cav-1 overexpression mice and knockout mice were used in this study.Cav-1-knockdown of RAW264.7 cells and mouse primary hepatocytes were performed to verify the changes in vitro.Moreover,a high-fat diet and palmitic acid plus oleic acid treatment were utilized to construct a NAFLD model in vivo and in vitro,respectively,while a high-iron diet was used to construct an in vivo iron overload model.Besides,iron concentration,the expression of Cav-1 and iron metabolism-related proteins in liver tissue or serum were detected using iron assay kit,Prussian blue staining,Western blotting,immunofluorescence staining,immunohistochemical staining and ELISA.The related indicators of lipid metabolism and oxidative stress were evaluated by the corresponding reagent kit and staining.Results:Significant disorder of lipid and iron metabolism occurred in NAFLD.The expression of Cav-1 was decreased in NAFLD hepatocytes(P<0.05),accompanied by iron metabolism disorder.Cav-1 enhanced the iron storage capacity of hepatocytes by activating the ferritin light chain/ferritin heavy chain pathway in NAFLD,subsequently alleviating the oxidative stress induced by excess ferrous ions in the liver.Further,CD68^(+) CD163^(+) macrophages expressing Cav-1 were found to accelerate iron accumulation in the liver,which was contrary to the effect of Cav-1 in hepatocytes.Positive correlations were also observed between the serum Cav-1 concentration and the serum iron-related protein levels in NAFLD patients and healthy volunteers(P<0.05).Conclusions:These findings confirm that Cav-1 is an essential target protein that regulates iron and lipid metabolic homeostasis.It is a pivotal molecule for predicting and protecting against the development of NAFLD.

Circulating microRNA expression and nonalcoholic fatty liver disease in adolescents with severe obesity

BACKGROUND Nonalcoholic fatty liver disease(NAFLD)is one of the most common chronic liver diseases in children and adolescents.NAFLD ranges in severity from isolated hepatic steatosis to nonalcoholic steatohepatitis(NASH),wherein hepatocellular inflammation and/or fibrosis coexist with steatosis.Circulating microRNA(miRNA)levels have been suggested to be altered in NAFLD,but the extent to which miRNA are related to NAFLD features remains unknown.This analysis tested the hypothesis that plasma miRNAs are significantly associated with histological features of NAFLD in adolescents.AIM To investigate the relationship between plasma miRNA expression and NAFLD features among adolescents with NAFLD.METHODS This study included 81 adolescents diagnosed with NAFLD and 54 adolescents without NAFLD from the Teen-Longitudinal Assessment of Bariatric Surgery study.Intra-operative core liver biopsies were collected from participants and used to characterize histological features of NAFLD.Plasma samples were collected during surgery for miRNA profiling.A total of 843 plasma miRNAs were profiled using the HTG EdgeSeq platform.We examined associations of plasma miRNAs and NAFLD features using logistic regression after adjusting for age,sex,race,and other key covariates.Ingenuity Pathways Analysis was used to identify biological functions of miRNAs that were associated with multiple histological features of NAFLD.RESULTS We identified 16 upregulated plasma miRNAs,including miR-193a-5p and miR-193b-5p,and 22 downregulated plasma miRNAs,including miR-1282 and miR-6734-5p,in adolescents with NAFLD.Moreover,52,16,15,and 9 plasma miRNAs were associated with NASH,fibrosis,ballooning degeneration,and lobular inflammation,respectively.Collectively,16 miRNAs were associated with two or more histological features of NAFLD.Among those miRNAs,miR-411-5p was downregulated in NASH,ballooning,and fibrosis,while miR-122-5p,miR-1343-5p,miR-193a-5p,miR-193b-5p,and miR-7845-5p were consistently and positively associated with all histological features of NAFLD.Pathway analysis revealed that most common pathways of miRNAs associated with multiple NAFLD features have been associated with tumor progression,while we also identified linkages between miR-122-5p and hepatitis C virus and between miR-199b-5p and chronic hepatitis B.CONCLUSION Plasma miRNAs were associated with NAFLD features in adolescent with severe obesity.Larger studies with more heterogeneous NAFLD phenotypes are needed to evaluate miRNAs as potential biomarkers of NAFLD.

Prevalence and risk factors for impaired renal function among Asian patients with nonalcoholic fatty liver disease

Background:Nonalcoholic fatty liver disease(NAFLD)is associated with impaired renal function,and both diseases often occur alongside other metabolic disorders.However,the prevalence and risk factors for impaired renal function in patients with NAFLD remain unclear.The objective of this study was to identify the prevalence and risk factors for renal impairment in NAFLD patients.Methods:All adults aged 18-70 years with ultrasound-diagnosed NAFLD and transient elastography examination from eight Asian centers were enrolled in this prospective study.Liver fibrosis and cirrhosis were assessed by FibroScan-aspartate aminotransferase(FAST),Agile 3+and Agile 4 scores.Impaired renal function and chronic kidney disease(CKD)were defined by an estimated glomerular filtration rate(eGFR)with value of<90 mL/min/1.73 m^(2) and<60 mL/min/1.73 m^(2),respectively,as estimated by the CKD-Epidemiology Collaboration(CKD-EPI)equation.Results:Among 529 included NAFLD patients,the prevalence rates of impaired renal function and CKD were 37.4%and 4.9%,respectively.In multivariate analysis,a moderate-high risk of advanced liver fibrosis and cirrhosis according to Agile 3+and Agile 4 scores were independent risk factors for CKD(P<0.05).Furthermore,increased fasting plasma glucose(FPG)and blood pressure were significantly associated with impaired renal function after controlling for the other components of metabolic syndrome(P<0.05).Compared with patients with normoglycemia,those with prediabetes[FPG≥5.6 mmol/L or hemoglobin A1c(HbA1c)≥5.7%]were more likely to have impaired renal function(P<0.05).Conclusions:Agile 3+and Agile 4 are reliable for identifying NAFLD patients with high risk of CKD.Early glycemic control in the prediabetic stage might have a potential renoprotective role in these patients.

Impact of lifestyle interventions on pathogenesis of nonalcoholic fatty liver disease

This editorial builds on the article titled“Establishment and validation of an adherence prediction system for lifestyle interventions in non-alcoholic fatty liver disease”by Zeng et al.We carried out a critical examination of nonalcoholic fatty liver disease(NAFLD)pathogenesis and how lifestyle interventions could facilitate disease resolution,particularly highlighting that non-alcoholic steatohepatitis(NASH)is a severe form of NAFLD.Our discussion details that weight loss is a pivotal factor in disease outcomes:A 3%-5%reduction is enough for resolution in 50%of non-obese individuals,while a 7%-10%reduction achieves similar benefits in obese individuals,as demonstrated by magnetic resonance spectroscopy.Additionally,the editorial underscores that such lifestyle changes are instrumental not only in resolving NAFLD but also in reversing hepatic steatosis and inflammation.These insights,derived from the research,emphasize the critical role of personalized lifestyle modifications in halting the progression of NAFLD to NASH and even reversing fibrosis,thus offering a template for effective patient management.

Validation of adherence prediction system for lifestyle interventions in nonalcoholic fatty liver disease

This editorial delves into the research article by Zeng et al published in the latest issue of World Journal of Gastroenterology.The manuscript contributes significantly to addressing the global health issue of nonalcoholic fatty liver disease(NAFLD)by introducing and validating the Exercise and Diet Adherence Scale(EDAS).The article effectively conveys the importance of the study,highlighting the prevalence of NAFLD,the lack of approved drugs for its treatment,and the crucial role of lifestyle correction.The use of the Delphi method for scale development and the subsequent evaluation of its reliability add scientific rigor to the methodology.The results demonstrate that the scale is correlated with key lifestyle indicators,which makes it a promising tool for assessing patient adherence to interventions.The identification of specific score thresholds for predicting adherence to daily calorie intake and exercise adds practical value to the scale.The differentiation among scores indicative of good,average,and poor adherence enhances its clinical applicability.In conclusion,the manuscript introduces EDAS,a valuable instrument that can contribute substantially to the field of NAFLD research and clinical practice.

Transient elastography with controlled attenuation parameter for the diagnosis of colorectal polyps in patients with nonalcoholic fatty liver disease

BACKGROUND The severity of nonalcoholic fatty liver disease(NAFLD)and lipid metabolism are related to the occurrence of colorectal polyps.Liver-controlled attenuation parameters(liver-CAPs)have been established to predict the prognosis of hepatic steatosis patients.AIM To explore the risk factors associated with colorectal polyps in patients with NAFLD by analyzing liver-CAPs and establishing a diagnostic model.METHODS Patients who were diagnosed with colorectal polyps in the Department of Gastroenterology of our hospital between June 2021 and April 2022 composed the case group,and those with no important abnormalities composed the control group.The area under the receiver operating characteristic curve was used to predict the diagnostic efficiency.Differences were considered statistically significant when P<0.05.RESULTS The median triglyceride(TG)and liver-CAP in the case group were significantly greater than those in the control group(mmol/L,1.74 vs 1.05;dB/m,282 vs 254,P<0.05).TG and liver-CAP were found to be independent risk factors for colorectal polyps,with ORs of 2.338(95%CI:1.154–4.733)and 1.019(95%CI:1.006–1.033),respectively(P<0.05).And there was no difference in the diagnostic efficacy between liver-CAP and TG combined with liver-CAP(TG+CAP)(P>0.05).When the liver-CAP was greater than 291 dB/m,colorectal polyps were more likely to occur.CONCLUSION The levels of TG and liver-CAP in patients with colorectal polyps are significantly greater than those patients without polyps.Liver-CAP alone can be used to diagnose NAFLD with colorectal polyps.

Investigating the causal associations between five anthropometric indicators and nonalcoholic fatty liver disease:Mendelian randomization study

BACKGROUND Although the etiology of nonalcoholic fatty liver disease(NAFLD)has not been thoroughly understood,the emerging roles of anthropometric indicators in assessing and predicting the risk of NAFLD have been highlighted by accumulating evidence.AIM To evaluate the causal relationships between five anthropometric indicators and NAFLD employing Mendelian randomization(MR)design.METHODS The Anthropometric Consortium provided genetic exposure data for five anthropometric indicators,including hip circumference(HC),waist circumference(WC),waist-to-hip ratio(WHR),body mass index(BMI),and body fat percentage(BF).Genetic outcome data for NAFLD were obtained from the United Kingdom Biobank and FinnGen Consortium.Genome-wide significant single nucleotide polymorphisms were chosen as instrumental variables.Univariable MR(UVMR)and multivariable MR(MVMR)designs with analytical approaches,including inverse variance weighted(IVW),MR-Egger,weighted median(WM),and weighted mode methods,were used to assess the causal relationships between anthropometric indicators and NAFLD.RESULTS Causal relationships were revealed by UVMR,indicating that a higher risk of NAFLD was associated with a perunit increase in WC[IVW:odds ratio(OR)=2.67,95%CI:1.42-5.02,P=2.25×10^(−3)],and BF was causally associated with an increased risk of NAFLD(WM:OR=2.23,95%CI:1.07-4.66,P=0.033).The presence of causal effects of WC on the decreased risk of NAFLD was supported by MVMR after adjusting for BMI and smoking.However,no causal association between BF and NAFLD was observed.In addition,other causal relationships of HC,WHR(BMI adjusted),and BMI with the risk of NAFLD were not retained after FDR correction.CONCLUSION This study establishes a causal relationship,indicating that an increase in WC is associated with a higher risk of NAFLD.This demonstrates that a suitable decrease in WC is advantageous for preventing NAFLD.

Influence of nonalcoholic fatty liver disease on response to antiviral treatment in patients with chronic hepatitis B:A meta-analysis

BACKGROUND Although hepatitis B virus infection is the leading cause of chronic liver injury globally,nonalcoholic fatty liver disease(NAFLD)is gradually gaining attention as another major chronic liver disease.The number of patients having chronic hepatitis B(CHB)with concomitant hepatic steatosis has increased.AIM To analyze the effect of NAFLD on the response to antiviral treatment in patients with CHB.METHODS Relevant English studies were systematically searched across PubMed,EMBASE,Web of Science,and Cochrane Library until October 2023.Studies in which the treatment outcomes were compared between patients with CHB only and those with CHB and hepatic steatosis were included.RESULTS Of the 2502 retrieved studies,11 articles were finally included.Biochemical response until 48 wk(OR=0.87,95%CI:0.50–1.53,P=0.000)and 96 wk(OR=0.35,95%CI:0.24–0.53,P=0.24)and virological response until 96 wk(OR=0.80,95%CI:0.43–1.49,P=0.097)were lower in patients with hepatic steatosis than in patients with CHB alone.CONCLUSION Hepatic steatosis lowers the biochemical response to antiviral treatment in patients with CHB.

Mapping the global research landscape on nonalcoholic fatty liver disease and insulin resistance:A visualization and bibliometric study

BACKGROUND Nonalcoholic fatty liver disease(NAFLD)is a liver condition that is prevalent worldwide and associated with significant health risks and economic burdens.As it has been linked to insulin resistance(IR),this study aimed to perform a bibliometric analysis and visually represent the scientific literature on IR and NAFLD.AIM To map the research landscape to underscore critical areas of focus,influential studies,and future directions of NAFLD and IR.METHODS This study conducted a bibliometric analysis of the literature on IR and NAFLD indexed in the SciVerse Scopus database from 1999 to 2022.The search strategy used terms from the literature and medical subject headings,focusing on terms related to IR and NAFLD.VOSviewer software was used to visualize research trends,collaborations,and key thematic areas.The analysis examined publication type,annual research output,contributing countries and institutions,funding agencies,journal impact factors,citation patterns,and highly cited references.RESULTS This analysis identified 23124 documents on NAFLD,revealing a significant increase in the number of publications between 1999 and 2022.The search retrieved 715 papers on IR and NAFLD,including 573(80.14%)articles and 88(12.31%)reviews.The most productive countries were China(n=134;18.74%),the United States(n=122;17.06%),Italy(n=97;13.57%),and Japan(n=41;5.73%).The leading institutions included the Universitàdegli Studi di Torino,Italy(n=29;4.06%),and the Consiglio Nazionale delle Ricerche,Italy(n=19;2.66%).The top funding agencies were the National Institute of Diabetes and Digestive and Kidney Diseases in the United States(n=48;6.71%),and the National Natural Science Foundation of China(n=37;5.17%).The most active journals in this field were Hepatology(27 publications),the Journal of Hepatology(17 publications),and the Journal of Clinical Endocrinology and Metabolism(13 publications).The main research hotspots were“therapeutic approaches for IR and NAFLD”and“inflammatory and high-fat diet impacts on NAFLD”.CONCLUSION This is the first bibliometric analysis to examine the relationship between IR and NAFLD.In response to the escalating global health challenge of NAFLD,this research highlights an urgent need for a better understanding of this condition and for the development of intervention strategies.Policymakers need to prioritize and address the increasing prevalence of NAFLD.

Pharmacodynamic study and mechanism of action of Linggui Zhugan Decoction in the intervention of Nonalcoholic fatty liver disease

Objective: To explore the therapeutic effect of Linggui Zhugan Decoction on nonalcoholic fatty liver disease through in vivo animal experiments, and to explore the mechanism of action of Linggui Zhugan Decoction in the intervention of nonalcoholic fatty liver disease through network pharmacology and molecular docking technology. Methods: A rat model of non- alcoholic fatty liver disease was established after 20 weeks of high-fat feeding, and the rats were divided into six groups, normal group, model group, simvastatin group (4 mg/kg), low- dose group of Linggui Zhugan Decoction (2.1 g/kg), medium-dose group of Linggui Zhugan Decoction (4.2 g/kg), and high-dose group of Linggui Zhugan Decoction (8.4 g/kg), and the liver morphological changes of HE staining and oil red O staining after the intervention of Linggui Zhugan Decoction were observed, and the microplate reader detected aspartate aminotransferase, alanine aminotransferase, Four levels of blood lipids. Network pharmacology combined with molecular docking was used to screen the potential mechanism and target of Linggui Zhugan Decoction for the intervention of non-alcoholic fatty liver disease. Results: Linggui Zhugan Decoction significantly improved the levels of alanine aminotransferase and alanine aminotransferase in model rats (P<0.05). HE staining and oil red O staining showed that Linggui Zhugan Decoction significantly reduced liver lipid deposition in rats in the model group. Linggui Zhugan Decoction could significantly reduce the quadruplical levels of blood lipids in model rats (P<0.05). Network pharmacology screened out 10 key targets and 5 key signaling pathways;The molecular docking results showed that the first 20 active ingredients all had good binding ability to the top 10 targets. Conclusion: The results show that Linggui Zhugan Decoction has the effect of regulating blood lipids and improving liver tissue lesions in non-alcoholic fatty liver disease, and preliminarily verifies the regulatory effect of Linggui Zhugan Decoction on lipid metabolism-related genes.

A Retrospective Analysis of Glucagon-Like Peptide 1 Receptor Agonists in Treating Type 2 Diabetes Mellitus Complicated by Nonalcoholic Fatty Liver Disease

Background: The objective of this study was to compare and analyze the variations in clinical indices before and after treatment of type 2 mellitus (T2DM) combined with nonalcoholic fatty liver disease (NAFLD) that were treated with glucagon-like peptide 1 receptor agonists (GLP-1RAs). Methods: The electronic medical record system was utilized to search for a total of 16 patients with type 2 diabetes complicated by NAFLD who were hospitalized at the First Affiliated Hospital of Yangtze University from October 2022 to April 2023 and treated with GLP-1RA for the first time. The clinical indices were compared before and after 12 weeks of treatment with GLP-1RA. Results: The liver-spleen CT ratio (L/S), alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) in all patients treated with GLP-1RA after 12 weeks were significantly different (P 0.05). The patients were categorized into two groups based on the types of GLP-1RAs. The changes in L/S, TC, TG, and LDL-C in the long-acting group after treatment were statistically significant (P Conclusions: GLP-1RAs can improve liver function, regulate lipid metabolism, and reduce the severity of fatty liver in patients with T2DM complicated by NAFLD, which demonstrates the importance of clinical applications.

Global trends and hotspots of treatment for nonalcoholic fatty liver disease:A bibliometric and visualization analysis(2010-2023)

BACKGROUND Nonalcoholic fatty liver disease(NAFLD)is chronic,with its progression leading to liver fibrosis and end-stage cirrhosis.Although NAFLD is increasingly common,no treatment guideline has been established.Many mechanistic studies and drug trials have been conducted for new drug development to treat NAFLD.An up-to-date overview on the knowledge structure of NAFLD through bibliometrics,focusing on research hotspots,is necessary to reveal the rational and timely directions of development in this field.AIM To research the latest literature and determine the current trends in treatment for NAFLD.METHODS Publications related to treatment for NAFLD were searched on the Web of Science Core Collection database,from 2010 to 2023.VOSviewers,CiteSpace,and R package“bibliometrix”were used to conduct this bibliometric analysis.The key information was extracted,and the results of the cluster analysis were based on network data for generating and investigating maps for country,institution,journal,and author.Historiography analysis,bursts and cluster analysis,cooccurrence analysis,and trend topic revealed the knowledge structure and research hotspots in this field.GraphPad Prism 9.5.1.733 and Microsoft Office Excel 2019 were used for data analysis and visualization.RESULTS In total,10829 articles from 120 countries(led by China and the United States)and 8785 institutions were included.The number of publications related to treatment for NAFLD increased annually.While China produced the most publications,the United States was the most cited country,and the United Kingdom collaborated the most from an international standpoint.The University of California-San Diego,Shanghai Jiao Tong University,and Shanghai University of Traditional Chinese Medicine produced the most publications of all the research institutions.The International Journal of Molecular Sciences was the most frequent journal out of the 1523 total journals,and Hepatology was the most cited and co-cited journal.Sanyal AJ was the most cited author,the most co-cited author was Younossi ZM,and the most influential author was Loomba R.The most studied topics included the epidemiology and mechanism of NAFLD,the development of accurate diagnosis,the precise management of patients with NAFLD,and the associated metabolic comorbidities.The major cluster topics were“emerging drug,”“glucagon-like peptide-1 receptor agonist,”“metabolic dysfunction-associated fatty liver disease,”“gut microbiota,”and“glucose metabolism.”CONCLUSION The bibliometric study identified recent research frontiers and hot directions,which can provide a valuable reference for scholars researching treatments for NAFLD.

Periodontal treatment and microbiome-targeted therapy in management of periodontitis-related nonalcoholic fatty liver disease with oral and gut dysbiosis

A growing body of evidence from multiple areas proposes that periodontal disease,accompanied by oral inflammation and pathological changes in the microbiome,induces gut dysbiosis and is involved in the pathogenesis of nonalcoholic fatty liver disease(NAFLD).A subgroup of NAFLD patients have a severely progressive form,namely nonalcoholic steatohepatitis(NASH),which is characterized by histological findings that include inflammatory cell infiltration and fibrosis.NASH has a high risk of further progression to cirrhosis and hepatocellular carcinoma.The oral microbiota may serve as an endogenous reservoir for gut microbiota,and transport of oral bacteria through the gastro-intestinal tract can set up a gut microbiome dysbiosis.Gut dysbiosis increases the production of potential hepatotoxins,including lipopolysaccharide,ethanol,and other volatile organic compounds such as acetone,phenol and cyclopentane.Moreover,gut dysbiosis increases intestinal permeability by disrupting tight junctions in the intestinal wall,leading to enhanced translocation of these hepatotoxins and enteric bacteria into the liver through the portal circulation.In particular,many animal studies support that oral administration of Porphyromonas gingivalis,a typical periodontopathic bacterium,induces disturbances in glycolipid metabolism and inflammation in the liver with gut dysbiosis.NAFLD,also known as the hepatic phenotype of metabolic syndrome,is strongly associated with metabolic complications,such as obesity and diabetes.Periodontal disease also has a bidirectional relationship with metabolic syndrome,and both diseases may induce oral and gut microbiome dysbiosis with insulin resistance and systemic chronic inflammation cooperatively.In this review,we will describe the link between periodontal disease and NAFLD with a focus on basic,epidemiological,and clinical studies,and discuss potential mechanisms linking the two diseases and possible therapeutic approaches focused on the microbiome.In conclusion,it is presumed that the pathogenesis of NAFLD involves a complex crosstalk between periodontal disease,gut microbiota,and metabolic syndrome.Thus,the conventional periodontal treatment and novel microbiome-targeted therapies that include probiotics,prebiotics and bacteriocins would hold great promise for preventing the onset and progression of NAFLD and subsequent complications in patients with periodontal disease.

Eight Zhes Decoction ameliorates the lipid dysfunction of nonalcoholic fatty liver disease using integrated lipidomics, network pharmacology and pharmacokinetics

Nonalcoholic fatty liver disease(NAFLD)has developed into the most common chronic liver disease and can lead to liver cancer.Our laboratory previously developed a novel prescription for NAFLD,“Eight Zhes Decoction”(EZD),which has shown good curative effects in clinical practice.However,the pharmacodynamic material basis and mechanism have not yet been revealed.A strategy integrating lipidomics,network pharmacology and pharmacokinetics was used to reveal the active components and mechanisms of EZD against NAFLD.The histopathological results showed that EZD attenuated the degrees of collagen deposition and steatosis in the livers of nonalcoholic steatofibrosis model mice.Furthermore,glycerophospholipid metabolism,arachidonic acid metabolism,glycerolipid metabolism and linoleic acid metabolism with phospholipase A2 group IVA(PLA2G4A)and cytochrome P450 as the core targets and 12,13-cis-epoxyoctadecenoic acid,12(S)-hydroxyeicosatetraenoic acid,leukotriene B4,prostaglandin E2,phosphatidylcholines(PCs)and triacylglycerols(TGs)as the main lipids were found to be involved in the treatment of NAFLD by EZD.Importantly,naringenin,artemetin,canadine,and bicuculline were identified as the active ingredients of EZD against NAFLD;in particular,naringenin reduces PC consumption by inhibiting the expression of PLA2G4A and thus promotes sufficient synthesis of very-low-density lipoprotein to transport excess TGs in the liver.This research provides valuable data and theoretical support for the application of EZD against NAFLD.

Emerging novel targets for nonalcoholic fatty liver disease treatment: Evidence from recent basic studies

Nonalcoholic fatty liver disease(NAFLD),a leading chronic disease worldwide,affects approximately a quarter of the global population.Nonalcoholic steatohepatitis(NASH)is an advanced form of NAFLD and is more likely to progress to liver fibrosis than simple steatosis.NASH is also identified as the most rapidly growing cause of hepatocellular carcinoma.Although in the past decade,several phase II/III clinical trials have shown promising results in the use of novel drugs targeting lipid synthase,farnesoid X receptor signaling,peroxisome proliferatoractivated receptor signaling,hepatocellular injury,and inflammatory signaling,proven pharmaceutical agents to treat NASH are still lacking.Thus,continuous exploration of the mechanism underlying the pathogenesis of NAFLD and the identification of novel therapeutic targets remain urgent tasks in the field.In the current review,we summarize studies reported in recent years that not only provide new insights into the mechanisms of NAFLD development but also explore the possibility of treating NAFLD by targeting newly identified signaling pathways.We also discuss evidence focusing on the intrahepatic targets involved in the pathogenesis of NAFLD as well as extrahepatic targets affecting liver metabolism and function.

Screening and interventions to prevent nonalcoholic fatty liver disease/nonalcoholic steatohepatitis-associated hepatocellular carcinoma

Liver cancer is the sixth most commonly diagnosed cancer worldwide,with hepatocellular carcinoma(HCC)comprising most cases.Besides hepatitis B and C viral infections,heavy alcohol use,and nonalcoholic steatohepatitis(NASH)-associated advanced fibrosis/cirrhosis,several other risk factors for HCC have been identified(i.e.old age,obesity,insulin resistance,type 2 diabetes).These might in fact partially explain the occurrence of HCC in non-cirrhotic patients without viral infection.HCC surveillance through effective screening programs is still an unmet need for many nonalcoholic fatty liver disease(NAFLD)patients,and identification of pre-cirrhotic individuals who progress to HCC represents a substantial challenge in clinical practice at the moment.Patients with NASHcirrhosis should undergo systematic HCC surveillance,while this might be considered in patients with advanced fibrosis based on individual risk assessment.In this context,interventions that potentially prevent NAFLD/NASH-associated HCC are needed.This paper provided an overview of evidence related to lifestyle changes(i.e.weight loss,physical exercise,adherence to healthy dietary patterns,intake of certain dietary components,etc.)and pharmacological interventions that might play a protective role by targeting the underlying causative factors and pathogenetic mechanisms.However,well-designed prospective studies specifically dedicated to NAFLD/NASH patients are still needed to clarify the relationship with HCC risk.

Association between Serum Uric Acid to HDL-Cholesterol Ratio and Nonalcoholic Fatty Liver Disease Risk among Chinese Adults

Objective The aim of this case-control study was to explore the association between serum uric acid to high density lipoprotein cholesterol ratio(UHR) and the risk of nonalcoholic fatty liver disease(NAFLD) in Chinese adults.Methods A total of 636 patients with NAFLD and 754 controls were enrolled from the Affiliated Hospital of Qingdao University, China, between January and December 2016. All patients completed a comprehensive questionnaire survey and underwent abdominal ultrasound examination and a blood test. NAFLD was diagnosed using ultrasonography after other etiologies were excluded. Logistic regression and restricted cubic spline model were conducted to evaluate the relationship of UHR with NAFLD risk.Results The multivariable adjusted odds ratio(95% confidence interval, CI) for NAFLD in the highest versus lowest quartile of UHR was 3.888(2.324–6.504). In analyses stratified by sex and age, we observed significant and positive associations between UHR and the risk of NAFLD in each subgroup. In analyses stratified by body mass index(BMI), a significant and positive association was found only in individuals with a BMI of ≥ 24 kg/m2. Our dose-response analysis indicated a linear positive correlation between UHR and the risk of NAFLD.Conclusion UHR is positively associated with the risk of NAFLD and may serve as an innovative and noninvasive marker for identifying individuals at risk of NAFLD.

Potential therapeutic targets for nonalcoholic fatty liver disease:Glucagon-like peptide 1

Nonalcoholic fatty liver disease(NAFLD)is the most rapidly growing contributor to liver mortality and morbidity.Hepatocellular injury in nonalcoholic steatohepatitis(NASH)is caused by an increase in metabolic substrates(glucose,fructose,and fatty acids),leading fatty acids to participate in pathways that cause cellular injury and a poor response to injury.The pathogenesis of this disease is largely associated with obesity,type 2 diabetes,and increasing age.To date,there are no Food and Drug Administration-approved treatments for NAFLD/NASH or its associated fibrosis.Since one of the pathogenic drivers of NASH is insulin resistance,therapies approved for the treatment of type 2 diabetes are being evaluated in patients with NASH.Currently,the glucagon-like peptide-1 receptor agonist(GLP-1RA)semaglutide is a safe,well-studied therapeutic for NAFLD/NASH patients.Existing research demonstrates that semaglutide can increase the resolution of NASH but not improve fibrosis.However,improving the fibrosis of NAFLD is the only way to improve the long-term prognosis of NAFLD.Given the complex pathophysiology of NASH,combining therapies with complementary mechanisms may be beneficial.Researchers have conducted trials of semaglutide in combination with antifibrotic drugs.However,the results have not fully met expectations,and it cannot be ruled out that the reason is the short trial time.We should continue to pay increasing attention to GLP-1RAs.

Gut microbiome and nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease(NAFLD)has become the most prevalent chronic liver disease globally and imposed a heavy economic burden on society and individuals.To date,the pathological process of NAFLD is not yet fully elucidated.Compelling evidences have demonstrated the pivotal role of gut microbiota in the pathogenesis of NAFLD,and gut dysbiosis has been commonly observed in patients with NAFLD.Gut dysbiosis impairs gut permeability,allowing the translocation of bacterial products such as lipopolysaccharides(LPS),short-chain fatty acids(SCFAs),and ethanol to the liver via portal blood flow.This review aimed to shed light on the underlying mechanisms by which gut microbiota influences the development and progression of NAFLD.In addition,the potential application of gut microbiome as a non-invasive diagnostic tool and a novel therapeutical target was reviewed.

Mitochondrial carnitine palmitoyltransferase-Ⅱ dysfunction: A possible novel mechanism for nonalcoholic fatty liver disease in hepatocarcinogenesis

Nonalcoholic fatty liver disease(NAFLD)or metabolic-associated fatty liver disease has been characterized by the lipid accumulation with injury of hepatocytes and has become one of the most common chronic liver diseases in the world.The complex mechanisms of NAFLD formation are still under identification.Carnitine palmitoyltransferase-Ⅱ(CPT-Ⅱ)on inner mitochondrial membrane(IMM)regulates long chain fatty acidβ-oxidation,and its abnormality has had more and more attention paid to it by basic and clinical research in NAFLD.The sequences of its peptide chain and DNA nucleotides have been identified,and the catalytic activity of CPT-Ⅱ is affected on its gene mutations,deficiency,enzymatic thermal instability,circulating carnitine level and so on.Recently,the CPT-Ⅱ dysfunction has been discovered in models of liver lipid accumulation.Meanwhile,the malignant transformation of hepatocyte-related CD44^(+) stem T cell activation,high levels of tumor-related biomarkers(AFP,GPC3)and abnormal activation of Wnt3a expression as a key signal molecule of the Wnt/β-catenin pathway run parallel to the alterations of hepatocyte pathology.This review focuses on some of the progress of CPT-Ⅱ inactivity on IMM with liver fatty accumulation as a possible novel pathogenesis for NAFLD in hepatocarcinogenesis.