Nonalcoholic fatty liver disease and liver transplantation - Where do we stand?

Dietary inflammatory index after liver transplantation: Associated effects and long-term outcomes

BACKGROUND & AIMS

We examined the dietary inflammatory potential in patients who underwent liver transplantation (LTx), associated factors and its relationship with clinical outcomes ten years after the initial evaluation.

METHODS

Dietary Inflammatory Index (DII®) scores were generated from data derived from the 24-h recall in 108 patients.

RESULTS

Patients with higher DII scores (highest tertile), indicating a pro-inflammatory diet, had significantly higher serum LDL cholesterol (108.0 vs 78.2 mg/dL, p = <0.01) at the initial evaluation. However, DII scores did not significantly predict the occurrence of clinical outcomes after ten years of follow-up. Patient age was predictive of neoplasia (OR:1.05 95% CI:1.00-1.11; p = 0.03). Higher BMI at the initial evaluation was associated with steatosis (OR:1.51; 95% CI:1.29-1.77; p < 0.01), and smoking history was associated with the occurrence of cardiovascular events (OR:7.71; 95% CI:1.53-38.79; p = 0.01).

CONCLUSIONS

A pro-inflammatory diet was associated with higher serum LDL cholesterol in the initial evaluation but may not be strongly related to clinical outcomes during long-term follow-up.

Prevalence of metabolic dysfunction-associated fatty liver disease and its association with glycemic control in persons with type 2 diabetes in Africa: A systematic review and meta-analysis

Metabolic dysfunction-associated fatty liver disease (MAFLD) and type 2 diabetes (T2D) are interconnected metabolic disorders with significant health implications. However, a comprehensive understanding of the extent of their co-occurrence in Africa is lacking. The aim of this review was to determine the prevalence of MAFLD and its association with glycemic control (HbA1c) in persons with T2D in Africa. A systematic search was conducted on PubMed, Medline, Embase, Scopus, Global Health, and Web of Science from their inception to December 6, 2023. Data on MAFLD prevalence and correlation coefficients regarding its association with glycemic control were pooled through random effect meta-analyses. Potential sources of heterogeneity were investigated using subgroup analysis and meta-regression. A total of 10 studies were included in the meta-analysis of MAFLD prevalence, while 2 were incorporated in the analysis of the association between MAFLD and glycemic control. The pooled prevalence of MAFLD in persons with T2D was 48.1% (95% CI: 36.1-60.3). The subgroup analysis revealed regional variations in MAFLD prevalence, with rates of 44.7% (95% CI: 28.7-62.0) in sub-Saharan Africa and 55.3% (95% CI: 36.2-73.0) in Northern Africa. Additionally, we observed an increasing trend in MAFLD prevalence, recording 55.1% (95% CI: 43.6-66.1) in the recent five years. There was a weak positive correlation between MAFLD and HbA1c (r = 0.33, 95% CI: 0.18-0.47). The findings of this study highlight a high prevalence of MAFLD in persons with T2D in Africa, with a suggested link between MAFLD and suboptimal glycemic control. Therefore, healthcare providers should prioritize the screening and management of MAFLD in individuals with T2D to enhance their metabolic health.

MASLD-Related HCC-Update on Pathogenesis and Current Treatment Options

Hepatocellular carcinoma (HCC) is a common complication of chronic liver diseases and remains a relevant cause of cancer-related mortality worldwide. The global prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) as a risk factor for hepatocarcinogenesis is on the rise. Early detection of HCC has been crucial in improving the survival outcomes of patients with metabolic dysfunction-associated steatohepatitis (MASH), even in the absence of cirrhosis. Understanding how hepatocarcinogenesis develops in MASH is increasingly becoming a current research focus. Additive risk factors such as type 2 diabetes mellitus (T2DM), genetic polymorphisms, and intestinal microbiota may have specific impacts. Pathophysiological and epidemiological associations between MASH and HCC will be discussed in this review. We will additionally review the available tumor therapies concerning their efficacy in MASH-associated HCC treatment.

Diagnostic Performance of Quantitative Ultrasound Parameters in Non-alcoholic Fatty Liver Disease

RATIONALE AND OBJECTIVES

Marked liver steatosis, steatohepatitis, and significant fibrosis are risk factors for unfavorable outcomes in non-alcoholic fatty liver disease (NAFLD). In this study, the diagnostic performance of attenuation coefficient (AC), liver stiffness (LS), and dispersion slope (DS) was evaluated separately and combined in the diagnosis of liver steatosis and fibrosis in NAFLD suspects using biopsy or magnetic resonance imaging (MRI) as a reference standard.

MATERIALS AND METHODS

Seventy-four NAFLD suspects were prospectively imaged with an Aplio i800 ultrasound scanner (Canon Medical Systems, Tustin, CA). AC, LS, and DS measurements were obtained from the right liver lobe.

RESULTS

Thirty-four patients underwent liver biopsy, and 40 had MRI. There were 32 patients (43%) with liver steatosis and fibrosis (S + F), 22 (30%) with steatosis (S), 5 (7%) with fibrosis (F), and 15 (20%) with normal liver (N). Mean ACs were significantly higher in steatotic livers (n = 54) than in non-steatotic livers (n = 20) (P < 0.0001). LS and DS were significantly higher in patients with liver fibrosis (n = 37) compared to non-fibrotic livers (n = 37) (P = 0.0004 and P = 0.0002, respectively). In detecting (S + F), the area under the receiver operating characteristic curve (AUROCC) was 0.87 for combined ultrasound parameters of LS and AC (negative predictive value [NPV]: 75%, positive predictive value [PPV]: 77%, P < 0.0001). In detecting patients with liver steatosis and fibrosis stage ≥2, LS had an AUROCC of 0.93 (NPV: 87%, PPV: 82%, P < 0.0001). In the biopsy group, 32% (11/34) were diagnosed with non-alcoholic steatohepatitis (NASH). DS values showed a significant difference among patients with (n = 23) or without (n = 11) hepatocellular ballooning (P = 0.02). AUROCC was 0.87 for combined ultrasound parameters of AC, LS, and DS with body mass index (BMI) in detecting NASH (NPV: 80%, PPV: 87%, P = 0.0006).

CONCLUSION

AC and LS showed high diagnostic value in detecting liver steatosis and fibrosis, respectively. The combined AC and LS values further improved the diagnostic accuracy in detecting NAFLD and high-risk NAFLD patients.

Non-alcoholic fatty liver disease and compromised endothelial function in people with type 2 diabetes

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) frequently coexists with type 2 diabetes mellitus (T2DM) and synergistically contributes to the development of atherosclerosis. Flow-mediated dilation (FMD) is a commonly used noninvasive test for assessing endothelial function. The main objective of this study was to explore FMD in patients with T2DM with and without NAFLD.

METHODS

In this cross-sectional study, conducted on people with T2DM, NAFLD was defined as controlled attenuation parameter (CAP) score > 302 dB/m. Endothelial dysfunction was detected when arterial FMD of brachial artery was equal or less than 0.7%. Regression analyses were applied to assess factors associated with impaired FMD.

RESULT

A total of 147 patients (72 with NAFLD and 75 without NAFLD) were included in the final analysis. Patients with NAFLD were more likely to develop FMD ≤ 7% (77.8% vs. 58.7%, P = 0.01). In multivariate analysis, NAFLD (OR = 2.581, 95% CI (1.18-5.62), P = 0.017) and hypertension (HTN) (OR = 3.114, 95% CI (1.31-7.35), P = 0.010) were associated with an increased risk of impaired FMD. However, female sex was associated with a decreased risk of impaired FMD (OR = 0.371, 95% CI (0.15-0.87), P = 0.024).

CONCLUSION

NAFLD is associated with endothelial dysfunction in people with T2DM. This risk is comparable with the risk imposed by HTN, highlighting the importance of screening and management of NAFLD in these patients.

TASL Practice Guidance on the Clinical Assessment and Management of Patients with Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a multisystem disease and is significantly associated with obesity, insulin resistance, type 2 diabetes mellitus, metabolic syndrome, and cardiovascular disease. NAFLD has become the most prevalent chronic liver disease in Western countries, and the proportion of NAFLD-related cirrhosis among patients on liver transplantation waiting lists has increased. In light of the accumulated data about NAFLD, and to provide a common approach with multi-disciplines dealing with the subject, it has become necessary to create new guidance for diagnosing and treating NAFLD. This guidance was prepared following an interdisciplinary study under the leadership of the Turkish Association for the Study of the Liver (TASL), Fatty Liver Special Interest Group. This new TASL Guidance is a practical application guide on NAFLD and was prepared to standardize the clinical approach to diagnosing and treating NAFLD patients. This guidance reflects many advances in the field of NAFLD. The proposals in this guidance are meant to aid decision-making in clinical practice. The guidance is primarily intended for gastroenterology, endocrinology, metabolism diseases, cardiology, internal medicine, pediatric specialists, and family medicine specialists.

Resection of NAFLD/NASH-related Hepatocellular Carcinoma (HCC): Clinical Features and Outcomes Compared with HCC Due to Other Etiologies

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are the leading causes of hepatocellular carcinoma (HCC) worldwide. Limited data exist on surgical outcomes for NAFLD/NASH-related HCC compared with other HCC etiologies. We evaluated differences in clinicopathological characteristics and outcomes of patients undergoing surgical resection for NAFLD/NASH-associated HCC compared with other HCC etiologies.

METHODS

Demographic, clinicopathological features, and survival outcomes of patients with surgically resected HCC were collected. NAFLD activity score (NAS) and fibrosis score were assessed by focused pathologic review in a subset of patients.

RESULTS

Among 492 patients screened, 260 met eligibility (NAFLD/NASH [n = 110], and other etiologies [n = 150]). Median age at diagnosis was higher in the NAFLD/NASH HCC cohort compared with the other etiologies cohort (66.7 vs. 63.4 years, respectively, P = .005), with an increased percentage of female patients (36% vs. 18%, P = .001). NAFLD/NASH-related tumors were more commonly >5 cm (66.0% vs. 45%, P = .001). There were no significant differences in rates of lymphovascular or perineural invasion, histologic grade, or serum AFP levels. The NAFLD/NASH cohort had lower rates of background liver fibrosis, lower AST and ALT levels, and higher platelet counts (P < .01 for all). Median overall survival (OS) was numerically shorter in NAFLD/NASH vs other etiology groups, however, not statistically significant.

CONCLUSIONS

Patients with NAFLD/NASH-related HCC more commonly lacked liver fibrosis and presented with larger HCCs compared with patients with HCC from other etiologies. No differences were seen in rates of other high-risk features or survival. With the caveat of sample size and retrospective analysis, this supports a similar decision-making approach regarding surgical resection for NAFLD/NASH and other etiology-related HCCs.

Hepatocyte apoptosis fragment product cytokeratin-18 M30 level and non-alcoholic steatohepatitis risk diagnosis: an international registry study

BACKGROUND

Liver biopsy for the diagnosis of non-alcoholic steatohepatitis (NASH) is limited by its inherent invasiveness and possible sampling errors. Some studies have shown that cytokeratin-18 (CK-18) concentrations may be useful in diagnosing NASH, but results across studies have been inconsistent. We aimed to identify the utility of CK-18 M30 concentrations as an alternative to liver biopsy for non-invasive identification of NASH.

METHODS

Individual data were collected from 14 registry centers on patients with biopsy-proven non-alcoholic fatty liver disease (NAFLD), and in all patients, circulating CK-18 M30 levels were measured. Individuals with a NAFLD activity score (NAS) ≥5 with a score of ≥1 for each of steatosis, ballooning, and lobular inflammation were diagnosed as having definite NASH; individuals with a NAS ≤2 and no fibrosis were diagnosed as having non-alcoholic fatty liver (NAFL).

RESULTS

A total of 2571 participants were screened, and 1008 (153 with NAFL and 855 with NASH) were finally enrolled. Median CK-18 M30 levels were higher in patients with NASH than in those with NAFL (mean difference 177 U/L; standardized mean difference [SMD]: 0.87 [0.69-1.04]). There was an interaction between CK-18 M30 levels and serum alanine aminotransferase, body mass index (BMI), and hypertension ( P  < 0.001, P  = 0.026 and P  = 0.049, respectively). CK-18 M30 levels were positively associated with histological NAS in most centers. The area under the receiver operating characteristics (AUROC) for NASH was 0.750 (95% confidence intervals: 0.714-0.787), and CK-18 M30 at Youden's index maximum was 275.7 U/L. Both sensitivity (55% [52%-59%]) and positive predictive value (59%) were not ideal.

CONCLUSION

This large multicenter registry study shows that CK-18 M30 measurement in isolation is of limited value for non-invasively diagnosing NASH.

Single-cell transcriptomics of hepatic stellate cells uncover crucial pathways and key regulators involved in non-alcoholic steatohepatitis

Background

Fibrosis is an important pathological process in the development of non-alcoholic steatohepatitis (NASH), and the activation of hepatic stellate cell (HSC) is a central event in liver fibrosis. However, the transcriptomic change of activated HSCs (aHSCs) and resting HSCs (rHSCs) in NASH patients has not been assessed. This study aimed to identify transcriptomic signature of HSCs during the development of NASH and the underlying key functional pathways.

Methods

NASH-associated transcriptomic change of HSCs was defined by single-cell RNA-sequencing (scRNA-seq) analysis, and those top upregulated genes were identified as NASH-associated transcriptomic signatures. Those functional pathways involved in the NASH-associated transcriptomic change of aHSCs were explored by weighted gene co-expression network analysis (WGCNA) and functional enrichment analyses. Key regulators were explored by upstream regulator analysis and transcription factor enrichment analysis.

Results

scRNA-seq analysis identified numerous differentially expressed genes in both rHSCs and aHSCs between NASH patients and healthy controls. Both scRNA-seq analysis and in-vivo experiments showed the existence of rHSCs (mainly expressing a-SMA) in the normal liver and the increased aHSCs (mainly expressing collagen 1) in the fibrosis liver tissues. NASH-associated transcriptomic signature of rHSC (NASHrHSCsignature) and NASH-associated transcriptomic signature of aHSC (NASHaHSCsignature) were identified. WGCNA revealed the main pathways correlated with the transcriptomic change of aHSCs. Several key upstream regulators and transcription factors for determining the functional change of aHSCs in NASH were identified.

Conclusion

This study developed a useful transcriptomic signature with the potential in assessing fibrosis severity in the development of NASH. This study also identified the main pathways in the activation of HSCs during the development of NASH.

Outcomes of Nonalcoholic Steatohepatitis After Liver Transplantation: An Updated Meta-Analysis and Systematic Review

BACKGROUND & AIMS

Nonalcoholic steatohepatitis (NASH) is the fastest growing indication of liver transplantation (LT) and is projected to be the leading cause of LT in the near future. The systemic pathogenesis of NASH increases risks of adverse clinical outcomes in patients with NASH receiving LT. Thus, this study aimed to conduct a time-dependent survival analysis between LT recipients with and without NASH using hazard ratios.

METHODS

A search was conducted on Medline and Embase databases for articles relating to LT outcomes for NASH recipients. A survival analysis was conducted of hazard ratios using the DerSimonian and Laird random-effects model with meta-regression. To account for censoring, survival data were reconstructed from published Kaplan-Meier curves and pooled to derive more accurate hazard estimates and all-cause mortality in NASH patients after LT. Pairwise meta-analysis was conducted to analyze secondary outcomes.

RESULTS

Fifteen studies involving 119,327 LT recipients were included in our analysis with a prevalence of NASH of 20.2% (95% CI, 12.9-30.2). The pooled 1-year, 5-year, and 10-year all-cause mortality in NASH patients after LT were 12.5%, 24.4%, and 37.9%, respectively. Overall survival was comparable between LT recipients for NASH vs non-NASH (hazard ratio, 0.910; 95% CI, 0.760 to 1.10; P = .34). Meta-regression showed that a higher model for end-stage liver disease score was associated with significantly worse overall survival in NASH compared with non-NASH after LT (95% CI, -0.0856 to -0.0181; P = .0026).

CONCLUSIONS

This study shows that patients undergoing LT for NASH cirrhosis have comparable complication rates, overall survival, and graft survival compared with non-NASH patients, although close monitoring may be indicated for those with higher model for end-stage liver disease scores.

Growing challenge of post-liver transplantation non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is one of the leading causes of chronic liver disease, cirrhosis, and hepatocellular carcinoma worldwide, with an estimated prevalence of 25%. Post-liver transplantation (LT) recurrent or de novo hepatic steatosis is a common complication in recipients, irrespective of transplantation indication. Risk factors for graft steatosis mainly include obesity, immunosuppression, donor steatosis, and genetic factors. Liver transplant recipients are at high risk of developing insulin resistance, new-onset diabetes, and post-transplantation metabolic syndrome that is highly associated with immunosuppressive treatment. Post-LT NAFLD is often underdiagnosed due to the poor sensitivity of most routine imaging methods. The gold standard for the diagnosis of hepatic steatosis is liver biopsy, which is, however, limited to more complex cases due to its invasive nature. There is no approved pharmacotherapy in NAFLD. Lifestyle modification remains the cornerstone in NAFLD treatment. Other treatment strategies in post-LT NAFLD include lifestyle modifications, pharmacotherapy, bariatric surgery, and tailored immunosuppression. However, these approaches originate from recommendations in the general population, as there is scarce data regarding the safety and efficacy of current management strategies for NAFLD in liver transplant patients. Future prospective studies are required to achieve tailored treatment for these patients.

The prevalence and incidence of NAFLD worldwide: a systematic review and meta-analysis

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide and the leading cause of liver-related morbidity and mortality. We aimed to predict the burden of NAFLD by examining and estimating the temporal trends of its worldwide prevalence and incidence.

METHODS

In this systematic review and meta-analysis, we searched MEDLINE, EMBASE, Scopus, and Web of Science without language restrictions for reports published between date of database inception and May 25, 2021. We included observational cross-sectional or longitudinal studies done in study populations representative of the general adult population, in whom NAFLD was diagnosed using an imaging method in the absence of excessive alcohol consumption and viral hepatitis. Studies were excluded if conducted in paediatric populations (aged <18 years) or subgroups of the general population. Summary estimates were extracted from included reports by KR and independently verified by HA using the population, intervention, comparison, and outcomes framework. Primary outcomes were the prevalence and incidence of NAFLD. A random-effects meta-analysis was used to calculate overall and sex-specific pooled effect estimates and 95% CIs.

FINDINGS

The search identified 28 557 records, of which 13 577 records were screened; 299 records were also identified via other methods. In total, 72 publications with a sample population of 1 030 160 individuals from 17 countries were included in the prevalence analysis, and 16 publications with a sample population of 381 765 individuals from five countries were included in the incidence analysis. The overall prevalence of NAFLD worldwide was estimated to be 32·4% (95% CI 29·9-34·9). Prevalence increased significantly over time, from 25·5% (20·1-31·0) in or before 2005 to 37·8% (32·4-43·3) in 2016 or later (p=0·013). Overall prevalence of NAFLD was significantly higher in men than in women (39·7% [36·6-42·8] vs 25·6% [22·3-28·8]; p<0·0001). The overall incidence of NAFLD was estimated to be 46·9 cases per 1000 person-years (36·4-57·5); 70·8 cases per 1000 person-years (48·7-92·8) in men and 29·6 cases per 1000 person-years (20·2-38·9) in women (p<0·0001). There was considerable heterogeneity between studies of both NAFLD prevalence (I²=99·9%) and NAFLD incidence (I²=99·9%).

INTERPRETATION

Worldwide prevalence of NAFLD is considerably higher than previously estimated and is continuing to increase at an alarming rate. Incidence and prevalence of NAFLD are significantly higher among men than among women. Greater awareness of NAFLD and the development of cost-effective risk stratification strategies are warranted to address the growing burden of NAFLD.

FUNDING

Canadian Institutes of Health.

Relatively Poor Long-term Outcomes Following Liver Transplantation for NASH in the United States

BACKGROUND

Nonalcoholic steatohepatitis (NASH) continues to increase in frequency as an indication for liver transplantation (LT). Data on long-term outcomes for these patients are limited. We aimed to compare long-term patient and graft survival in patients undergoing LT for NASH in the United States to other indications.

METHODS

We analyzed data from the Scientific Registry of Transplant Recipients of adult patients who underwent primary deceased-donor LT from January 1, 2005, to December 31, 2019.

RESULTS

NASH has increased as an indication for LT by 4.5-fold, from 5.2% in 2005 to 23.4% in 2019. Patient (61.2%) and graft survival (59.2%) at 10 y are significantly poorer for NASH than for all other indications other than alcohol. Patients transplanted for NASH have higher body mass index (32.2 versus 27.6) and greater frequency of diabetes (13% versus 11.6%) than any other indication (P < 0.001). Portal vein thrombosis, location in intensive care unit, dialysis, and pre-LT diabetes (P < 0.001 for all) are independently predictive of patient death and graft loss. Body mass index is not predictive. NASH patients undergoing simultaneous liver kidney have markedly worse 10-y patient and graft survival than liver-only (52.3% versus 62.1%). Graft loss was attributed to recurrence of NASH in <1% of patients.

CONCLUSIONS

LT for NASH is associated with relatively poor long-term patient and graft survival when compared with patients transplanted for other indications, NASH patients undergoing simultaneous liver kidney have the worst long-term outcomes.

Thyroid Hormone Decreases Hepatic Steatosis, Inflammation, and Fibrosis in a Dietary Mouse Model of Nonalcoholic Steatohepatitis

Background: Nonalcoholic steatohepatitis (NASH) is characterized by hepatic steatosis, lobular inflammation, and fibrosis. Thyroid hormone (TH) reduces steatosis; however, the therapeutic effect of TH on NASH-associated inflammation and fibrosis is not known. This study examined the therapeutic effect of TH on hepatic inflammation and fibrosis during NASH and investigated THs molecular actions on autophagy and mitochondrial biogenesis. Methods: HepG2-TRβ cells were treated with bovine serum albumin-conjugated palmitic acid (PA) to mimic lipotoxic conditions in vitro. Mice with NASH were established by feeding C57BL/6J mice Western diet with 15% fructose in drinking water for 16 weeks. These mice were administered triiodothyronine (T3)/thyroxine (T4) supplemented in drinking water for the next eight weeks. Results: In cultured HepG2-TRβ cells, TH treatment increased mitochondrial respiration and fatty acid oxidation under basal and PA-treated conditions, as well as decreased lipopolysaccharides and PA-stimulated inflammatory and fibrotic responses. In a dietary mouse model of NASH, TH administration decreased hepatic triglyceride content (3.19 ± 0.68 vs. 8.04 ± 0.42 mM/g liver) and hydroxyproline (1.44 ± 0.07 vs. 2.58 ± 0.30 mg/g liver) when compared with mice with untreated NASH. Metabolomics profiling of lipid metabolites showed that mice with NASH had increased triacylglycerol, diacylglycerol, monoacylglycerol, and hepatic cholesterol esters species, and these lipid species were decreased by TH treatment. Mice with NASH also showed decreased autophagic degradation as evidenced by decreased transcription Factor EB and lysosomal protease expression, and accumulation of LC3B-II and p62. TH treatment restored the level of lysosomal proteins and resolved the accumulation of LC3B-II and p62. Impaired mitochondrial biogenesis was also restored by TH. The simultaneous restoration of autophagy and mitochondrial biogenesis by TH increased β-oxidation of fatty acids. Additionally, the elevated oxidative stress and inflammasome activation in NASH liver were also decreased by TH. Conclusions: In a mouse model of NASH, TH restored autophagy and mitochondrial biogenesis to increase β-oxidation of fatty acids and to reduce lipotoxicity, oxidative stress, hepatic inflammation, and fibrosis. Activating thyroid hormone receptor in the liver may represent an effective strategy for NASH treatment.

COVID-19 and liver diseases, what we know so far

Coronavirus disease 2019 (COVID-19) pneumonia outbreak started in December 2019. On March 12, 2020, the World Health Organization (WHO) declared that the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) constitutes a pandemic, and as of May 2021, SARS-CoV-2 has infected over 167.3 million patients, including 3.4 million deaths, reported to WHO. In this review, we will focus on the relationship between SARS-CoV-2 infection and the liver. We will discuss how chronic liver diseases affect the COVID-19 disease course and outcomes. We will also discuss the SARS-CoV-2 effects on the liver, mechanisms of acute liver injury, and potential management plans.

Induction of Accelerated Aging in a Mouse Model

With the global increase of the elderly population, the improvement of the treatment for various aging-related diseases and the extension of a healthy lifespan have become some of the most important current medical issues. In order to understand the developmental mechanisms of aging and aging-related disorders, animal models are essential to conduct relevant studies. Among them, mice have become one of the most prevalently used model animals for aging-related studies due to their high similarity to humans in terms of genetic background and physiological structure, as well as their short lifespan and ease of reproduction. This review will discuss some of the common and emerging mouse models of accelerated aging and related chronic diseases in recent years, with the aim of serving as a reference for future application in fundamental and translational research.

Histone deacetylase inhibitor givinostat attenuates nonalcoholic steatohepatitis and liver fibrosis

Nonalcoholic steatohepatitis (NASH) is a common chronic liver disease that is increasingly prevalent worldwide. Liver inflammation is an important contributor to disease progression from nonalcoholic fatty liver (NAFL) to NASH, but there is a lack of efficient therapies. In the current study we evaluated the therapeutic potential of givinostat, a histone deacetylase (HDAC) inhibitor, in the treatment of NASH in vivo and in vitro. Liver inflammation was induced in mice by feeding a methionine- and choline-deficient diet (MCD) or a fructose, palmitate, cholesterol diet (FPC). The mice were treated with givoinostat (10 mg·kg^-1·d^-1, ip) for 8 or 10 weeks. At the end of the experiment, the livers were harvested for analysis. We showed that givoinostat administration significantly alleviated inflammation and attenuated hepatic fibrosis in MCD-induced NASH mice. RNA-seq analysis of liver tissues form MCD-fed mice revealed that givinostat potently blocked expression of inflammation-related genes and regulated a broad set of lipid metabolism-related genes. In human hepatocellular carcinoma cell line HepG2 and human derived fetal hepatocyte cell line L02, givinostat significantly decreased palmitic acid-induced intracellular lipid accumulation. The benefit of givinostat was further confirmed in FPC-induced NASH mice. Givinostat administration significantly attenuated hepatic steatosis, inflammation as well as liver injury in this mouse model. In conclusion, givinostat is efficacious in reversing diet-induced NASH, and may serve as a therapeutic agent for the treatment of human NASH.

Visceral Fat Area Is an Independent Risk Factor for Overweight or Obese Nonalcoholic Fatty Liver Disease in Potential Living Liver Donors

BACKGROUND

The present study aimed to evaluate the correlation between hepatic steatosis (HS), determined by biopsy, and visceral adiposity, measured by computed tomography (CT), in overweight or obese potential living liver donors, and to investigate the risk factors for overweight or obese nonalcoholic fatty liver disease (NAFLD).

METHODS

This retrospective study included 375 overweight or obese (body mass index ≥23 kg/m²) potential living liver donors (mean age, 30.4 ± 9.5 years; 273 men) who underwent liver biopsies and abdominal CT examinations in 2017 and 2018. Anthropometry, laboratory parameters, body composition, and HS were assessed. Correlations were analyzed using Pearson's correlation coefficient, and logistic regression was used to identify independent predictors of overweight or obese NAFLD.

RESULTS

Visceral fat area (VFA) was positively correlated with the degree of HS in men (r = 0.307; P < .001) and women (r = 0.387; P < .001). Multivariable logistic regression analysis showed that alanine aminotransferase (odds ratio [OR], 1.017; 95% confidence interval [CI], 1.001-1.033; P = .033) and VFA (OR, 1.015; 95% CI, 1.008-1.022; P < .001) were independent risk factors for overweight or obese NAFLD in men, and VFA (OR, 1.029; 95% CI, 1.011-1.047; P = .002) was an independent risk factor for overweight or obese NAFLD in women.

CONCLUSION

Visceral adiposity was positively correlated with the degree of HS in overweight or obese potential living liver donors. Additionally, visceral adiposity may be an independent risk factor for overweight or obese NAFLD in potential living liver donors.

The molecular phenotypes of injury, steatohepatitis, and fibrosis in liver transplant biopsies in the INTERLIVER study

To extend previous molecular analyses of rejection in liver transplant biopsies in the INTERLIVER study (ClinicalTrials.gov #NCT03193151), the present study aimed to define the gene expression selective for parenchymal injury, fibrosis, and steatohepatitis. We analyzed genome-wide microarray measurements from 337 liver transplant biopsies from 13 centers. We examined expression of genes previously annotated as increased in injury and fibrosis using principal component analysis (PCA). PC1 reflected parenchymal injury and related inflammation in the early posttransplant period, slowly regressing over many months. PC2 separated early injury from late fibrosis. Positive PC3 identified a distinct mildly inflamed state correlating with histologic steatohepatitis. Injury PCs correlated with liver function and histologic abnormalities. A classifier trained on histologic steatohepatitis predicted histologic steatohepatitis with cross-validated AUC = 0.83, and was associated with pathways reflecting metabolic abnormalities distinct from fibrosis. PC2 predicted histologic fibrosis (AUC = 0.80), as did a molecular fibrosis classifier (AUC = 0.74). The fibrosis classifier correlated with matrix remodeling pathways with minimal overlap with those selective for steatohepatitis, although some biopsies had both. Genome-wide assessment of liver transplant biopsies can not only detect molecular changes induced by rejection but also those correlating with parenchymal injury, steatohepatitis, and fibrosis, offering potential insights into disease mechanisms for primary diseases.

The Accuracy of Serum Biomarkers in the Diagnosis of Steatosis, Fibrosis, and Inflammation in Patients with Nonalcoholic Fatty Liver Disease in Comparison to a Liver Biopsy

Background and Objective: This study was conducted to evaluate the diagnostic performance of various biomarkers for steatosis, fibrosis, and inflammation in comparison to a liver biopsy (LB) in patients with nonalcoholic fatty liver disease (NAFLD). Materials and Methods: This was a cross-sectional study that included 135 patients with biopsy-proven NAFLD. Fatty liver index (FLI), hepatic steatosis index (HSI), cell death markers (CK-18 M30 and CK-18 M65), FIB-4 index, NAFLD fibrosis score (NFS), BARD, and AST to platelet ratio index (APRI) were calculated and analysed. Results: FLI, HSI scores, and the cell death biomarkers showed poor diagnostic accuracy for steatosis detection and quantification, with an area under the curve (AUC) of <0.70. The cell death biomarkers likewise did not perform well for the detection of nonalcoholic steatohepatitis (NASH) (AUC < 0.7). As for the fibrosis staging, only APRI and the cell death biomarkers had moderate accuracy (AUC > 0.7) for advanced fibrosis, whereas FIB-4, BARD, and NFS scores demonstrated poor performance (AUC < 0.70). However, a combination of FIB-4 and NFS with the cell death biomarkers had moderate accuracy for advanced (≥F3) fibrosis detection, with an AUC of >0.70. Conclusions: In this first study on Croatian patients with NAFLD, serum biomarkers demonstrated poor diagnostic performance for the noninvasive diagnosis of liver steatosis and NASH. APRI and the cell death biomarkers had only moderate accuracy for diagnosing advanced fibrosis, as did the combination of FIB-4 and NFS with the cell death biomarkers. Further studies regarding serum biomarkers for all NAFLD stages are needed.

Computed Tomography-Based Radiomic Analysis for Preoperatively Predicting the Macrovesicular Steatosis Grade in Cadaveric Donor Liver Transplantation

This study is aimed at determining the ability of computed tomography- (CT-) based radiomic analysis to distinguish between grade 0/1 and grade 2/3 macrovesicular steatosis (MaS) in cadaveric donor liver transplantation cases. Preoperative noncontrast-enhanced CT images of 150 patients with biopsy-confirmed MaS were analyzed retrospectively; these patients were classified into the low-grade MaS (n = 100, grade 0 or 1) and high-grade MaS (n = 50, grade 2 or 3) groups. Three-dimensional spherical regions of interest of 40 pixel (2.5 cm) in diameter were placed in the right anterior and left lateral segments of the liver. Thereafter, 300 regions of interest (ROIs) were segmented and randomly assigned to the training and testing groups at a ratio of 7 : 3. A total of 402 radiomic features were extracted from each ROI. For MaS classification, a radiomic model was established using multivariate logistic regression analysis. Clinical data, including age, sex, and liver function, were collected to establish the clinical model at the patient level. The performances of the radiomic and clinical models, i.e., the diagnostic discrimination, calibration, and clinical utilities, were evaluated. The radiomic model, with seven selected features, depicted a good discrimination with an area under the receiver operating characteristic curve (AUC) of 0.907 (95% confidence interval (CI): 0.869–0.940) in the training cohort and 0.906 (95% CI: 0.843–0.959) in the testing cohort. The calibration curve revealed good agreement between the predicted and observed probabilities in the training and testing cohorts (both P > 0.05 in the H-L test). Decision curve analysis revealed that the radiomic model was more beneficial than the treat-all or treat-none schemes for predicting the MaS grade. Alanine transaminase and gamma-glutamyl transferase were used for building the clinical model, and the AUC was 0.784 in the total cohort. The CT-based radiomic model outperforming the conventional clinical model could provide an important reference for MaS grading in cadaveric liver donors.

Machine Learning Approach to Classify Cardiovascular Disease in Patients With Nonalcoholic Fatty Liver Disease in the UK Biobank Cohort

Background Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver disease worldwide. Cardiovascular disease (CVD) is the leading cause of mortality among patients with NAFLD. The aim of our study was to develop a machine learning algorithm integrating clinical, lifestyle, and genetic risk factors to identify CVD in patients with NAFLD. Methods and Results We created a cohort of patients with NAFLD from the UK Biobank, diagnosed according to proton density fat fraction from magnetic resonance imaging data sets. A total of 400 patients with NAFLD with subclinical atherosclerosis or clinical CVD, defined by disease codes, constituted cases and 446 NAFLD cases with no CVD constituted controls. We evaluated 7 different supervised machine learning approaches on clinical, lifestyle, and genetic variables for identifying CVD in patients with NAFLD. The most significant clinical and lifestyle variables observed by the predictive modeling were age (59 years [54.00-63.00 years]), hypertension (145 mm Hg [134.0-156.0 mm Hg] and 85 mm Hg [79.00-93.00 mm Hg]), waist circumference (98 cm [95.00-105.00 cm]), and sedentary lifestyle, defined as time spent watching TV >4 h/d. In the genetic data, single-nucleotide polymorphisms in IL16 and ANKLE1 gene were most significant. Our proposed ensemble-based integrative machine learning model achieved an area under the curve of 0.849 using the random forest modeling for CVD prediction. Conclusions We propose a machine learning algorithm that identifies CVD in patients with NAFLD through integration of significant clinical, lifestyle, and genetic risk factors. These patients with NAFLD at higher risk of CVD should be flagged for screening and aggressive treatment of their cardiometabolic risk factors to prevent cardiovascular morbidity and mortality.

Drug Therapy for Non-Alcoholic Steatohepatitis-Induced Liver Fibrosis

Aim. An overview of current pharmacotherapy for non-alcoholic steatohepatitis (NASH)-associated liver fibrosis.

Key points. In current clinical recommendations, therapeutic measures in non-alcoholic fatty liver disease should include lifestyle change, body weight normalisation, NASH-associated liver fibrosis-specific drug therapy and treatment for metabolic syndrome-related diseases. Given a lack of approved antifibrotic therapies in NASH, several drugs have nevertheless demonstrated an adequate efficacy and safety in phase 3 clinical trials, also in compensated cirrhosis, which allows their practical validation in phase 4.

Conclusion. The understanding of liver fibrosis as an adverse natural consequence of non-alcoholic fatty liver disease clearly attests for an early introduction and wide use of antifibrotic therapy to improve NASH outcomes and avoid associated complications.

 

Non-alcoholic steatohepatitis in liver transplant recipients diagnosed by serum cytokeratin 18 and transient elastography: A prospective study

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) seem common after liver transplantation.

AIM

To investigate incidence and predictors of NAFLD and NASH by employing noninvasive testing in liver transplant recipients, namely controlled attenuation parameter (CAP) and the serum biomarker cytokeratin 18 (CK-18). We also evaluated the diagnostic accuracy of CK-18 and CAP compared to liver histology.

METHODS

We prospectively recruited consecutive adult patients who received liver transplant at the McGill University Health Centre between 2015-2018. Serial measurements of CK-18 and CAP were recorded. NAFLD and NASH were diagnosed by CAP ≥ 270 dB/m, and a combination of CAP ≥ 270 dB/m with CK-18 > 130.5 U/L, respectively. Incidences and predictors of NAFLD and NASH were investigated using survival analysis and Cox proportional hazards.

RESULTS

Overall, 40 liver transplant recipients (mean age 57 years; 70% males) were included. During a median follow-up of 16.8 mo (interquartile range 15.6-18.0), 63.0% and 48.5% of patients developed NAFLD and NASH, respectively. On multivariable analysis, after adjusting for sex and alanine aminotransferase, body mass index was an independent predictor of development of NAFLD [adjusted hazard ratio (aHR): 1.21, 95% confidence interval (CI): 1.04-1.41; P = 0.01] and NASH (aHR: 1.26, 95%CI: 1.06-1.49; P < 0.01). Compared to liver histology, CAP had a 76% accuracy to diagnose NAFLD, while the accuracy of CAP plus CK-18 to diagnose NASH was 82%.

CONCLUSION

NAFLD and NASH diagnosed non-invasively are frequent in liver transplant recipients within the first 18 mo. Close follow-up and nutritional counselling should be planned in overweight patients.

Hsa_circ_0007059 sponges miR-421 to repress cell growth and stemness in hepatocellular carcinoma by the PTEN-AKT/mTOR pathway

BACKGROUND

Hepatocellular carcinoma (HCC) is a substantial health concern worldwide. Increasing studies have suggested that circle RNAs (circRNAs) function as new regulators in HCC progression. The present work explored the role of hsa_circ_0007059 (circ_0007059) in the developing process of hepatocarcinogenesis.

METHODS

The circ_0007059 level in HCC was determined by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) and northern blot. Its biological role in HCC cells was assessed using 3-(4,5-Dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide (MTT), colony formation, flow cytometry, Transwell, sphere formation and western blotting analyses. Bioinformatics analysis, luciferase reporter, and RNA immunoprecipitation (RIP) assays were used to test the regulatory mechanisms of circ_0007059.

RESULTS

Our results revealed that circ_0007059 expression was downregulated in HCC samples and cells. Moreover, circ_0007059 overexpression inhibited HCC cell proliferation, migration, invasion, and stem cell-like property, and strengthened cell apoptosis. In mechanism, circ_0007059 suppressed AKT/mTOR pathway by positively regulating phosphatase and tensin homolog (PTEN) expression. Additionally, circ_0007059 acted as a positive regulator of PTEN through controlling the availability of miR-421. Rescue assays demonstrated that PTEN knockdown or SC79 (AKT agonist) eliminated the effect of circ_0007059 on HCC cell phenotypes.

CONCLUSION

Circ_0007059 sponges miR-421 to inhibit oncogenic cellular process in HCC by mediating the PTEN-AKT/mTOR pathway.

The Role of Vitamin Deficiency in Liver Disease: To Supplement or Not Supplement?

Over the past few years, growing interest has been shown for the impact of dietary requirements and nutritional factors on chronic diseases. As a result, nutritional programs have been reinforced by public health policies. The precise role of micronutrients in chronic liver disease is currently receiving particular attention since abnormalities in vitamin levels are often detected. At present, treatment programs are focused on correcting vitamin deficiencies, which are frequently correlated to higher rates of comorbidities with poor outcomes. The literature reviewed here indicates that liver diseases are often related to vitamin disorders, due to both liver impairment and abnormal intake. More specific knowledge about the role of vitamins in liver disease is currently emerging from various results and recent evidence. The most significant benefits in this area may be observed when improved vitamin intake is combined with a pharmacological treatment that may also affect the progression of the liver disease, especially in the case of liver tumors. However, further studies are needed.

Fructose Consumption and Hepatocellular Carcinoma Promotion

Hepatocellular carcinoma (HCC) accounts for 85% of primary liver cancer, the third most common cause of cancer-related deaths worldwide. Its incidence has been increasing in both men and women. In Western countries, high-calorie diets, mainly rich in carbohydrates such as fructose, represent a significant concern due to their repercussions on the population’s health. A high-fructose diet is related to the development of Metabolic-Associated Fatty Liver Disease (MAFLD), formerly named Non-Alcoholic Fatty Liver Disease (NAFLD), and the progression of HCC as it potentiates the lipogenic pathway and the accumulation of lipids. However, fructose metabolism seems to be different between the stages of the disease, carrying out a metabolic reprogramming to favor the proliferation, inflammation, and metastatic properties of cancer cells in HCC. This review focuses on a better understanding of fructose metabolism in both scenarios: MAFLD and HCC.

Non-alcoholic fatty liver disease: A patient guideline

This patient guideline is intended for all patients at risk of or living with non-alcoholic fatty liver disease (NAFLD). NAFLD is the most frequent chronic liver disease worldwide and comes with a high disease burden. Yet, there is a lot of unawareness. Furthermore, many aspects of the disease are still to be unravelled, which has an important impact on the information that is given (or not) to patients. Its management requires a close interaction between patients and their many healthcare providers. It is important for patients to develop a full understanding of NAFLD in order to enable them to take an active role in their disease management. This guide summarises the current knowledge relevant to NAFLD and its management. It has been developed by patients, patient representatives, clinicians and scientists and is based on current scientific recommendations, intended to support patients in making informed decisions.

Traditional Chinese medicine in the treatment of nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) is a common chronic liver disease in clinical practice. It has been considered that NASH is one of the main causes of chronic liver disease, cirrhosis and carcinoma. The mechanism of the NASH progression is complex, including lipid metabolism dysfunction, insulin resistance, oxidative stress, inflammation, apoptosis, fibrosis and gut microbiota dysbiosis. Except for lifestyle modification and bariatric surgery, there has been no pharmacological therapy that is being officially approved in NASH treatment. Traditional Chinese medicine (TCM), as a conventional and effective therapeutic strategy, has been proved to be beneficial in treating NASH in numbers of studies. In the light of this, TCM may provide a potential therapy for treating NASH. In this review, we summarized the associated mechanisms of action TCM treating NASH in preclinical studies and systematically analysis the effectiveness of TCM treating NASH in current clinical trials.

Non-alcoholic fatty liver disease and obesity among adult donors are major challenges to living donor liver transplantation: A single-centre experience

OBJECTIVES

Obesity and non-alcoholic fatty liver disease (NAFLD) are rampant in South East Asia. There is paucity of data exploring its' impact on donor suitability for living donor liver transplantation (LDLT). We aimed to describe and examine the factors related to non-utilization of potential donors in our LDLT programme.

METHODS

This is an analysis of prospectively collected data on potential donors for an adult LDLT programme, between January 2017 and December 2019.

RESULTS

Fifty-five donors for 33 potential recipients were evaluated. The mean age was 31.6 ± 8.5 years, 52.7% were female and the ethnic divisions were: Chinese (50.9%), Indian (25.5%) and Malay (23.6%). The mean body mass index (BMI) among potential donors was 25.1 ± 4.0 kg/m²; 25.5% of donors had normal BMI, 23.6% were overweight and 50.9% were obese. Using the CAP modality of Fibroscan®, we identified the following grades of hepatic steatosis: 36.6% S0, 19.5% S1, 2.4% S2 and 41.5% S3. The non-utilization rate of our donors was 74.5% (41/55) and the main reasons were significant hepatic steatosis and/or obesity. Compared to suitable donors, unsuitable donors had significantly greater mean BMI, mean CAP scores, higher rates of dyslipidaemia and NAFLD.

CONCLUSION

NAFLD and obesity represent major challenges to an emerging LDLT programme in Malaysia.

Trends in indications and outcomes of liver transplantation in Canada: A multicenter retrospective study

The liver transplantation (LT) landscape is continuously evolving. We sought to evaluate trends in indications for LT in Canada and the impact of primary liver disease on post-LT outcomes using a national transplant registry. Adult patients who underwent a primary LT between 2000 and 2018 were retrospectively identified in the Canadian Organ Replacement Registry. Outcomes included post-LT patient and graft survival. A total of 5,722 LTs were identified. The number of LT per year increased from 251 in 2000 to 349 in 2018. The proportion of patients transplanted for HCV decreased from 31.5% in 2000 to 3.4% in 2018. In contrast, the percentage of transplants for HCC increased from 2.3% in 2000 to 32.4% in 2018, and those performed for NASH increased from 0.4% in 2005 to 12.6% in 2018. Year of transplant (per 1 year) was protective for both patient (HR:0.96,95%CI:0.94-0.97; P < 0.001) and graft survival (HR:0.97, 95%CI: 0.96-0.99; P = 0.001). Post-LT outcomes have improved over time in this nationwide analysis spanning 18 years. Moreover, trends in the indications for LT have changed, with HCC becoming the leading etiology. The decrease in the proportion of HCV patients and increase in those with NASH has implications on the evolving management of LT patients.

Limitations of current liver donor allocation systems and the impact of newer indications for liver transplantation

Liver transplantation represents a life-saving treatment for patients with decompensated cirrhosis, a severe condition associated with a high risk of waiting list mortality. When decompensation occurs rapidly in the presence of extrahepatic organ failures, the condition is called acute-on-chronic liver failure, which is associated with an even higher risk of death, though liver transplantation can also markedly improve survival in affected patients. However, there are still gaps in our understanding of how to optimise prioritisation and organ allocation, as well as survival among patients with acute-on-chronic liver failure (both before and after transplant). Moreover, it is urgent to address inequalities in access to liver transplantation in patients with severe alcoholic hepatitis and non-alcoholic steatohepatitis. Several controversies still exist regarding gender and regional disparities, as well as the use of suboptimal donor grafts. In this review, we aim to provide a critical perspective on the role of liver transplantation in patients with decompensated cirrhosis and address areas of ongoing uncertainty.

Controlled attenuation parameter measured using transient elastography for the noninvasive assessment of macrovesicular steatosis in potential living liver donors

PURPOSE

This study aimed to determine the diagnostic performance of the controlled attenuation parameter (CAP) measured using transient elastography (TE) for assessing macrovesicular steatosis (MaS) in potential living liver donors using same-day biopsy as a reference standard.

METHODS

This retrospective study included 204 living liver donor candidates who underwent TE and liver biopsy on the same day between July 2013 and June 2014. The histologic degree of MaS was determined. The area under the receiver operating characteristic curve (AUROC) was used to evaluate the performance of CAP for diagnosing MaS of >10%, and the optimal cutoff value was identified using the maximal Youden index.

RESULTS

Based on liver biopsy, 185 subjects had MaS of ≤10% and 19 had MaS of >10%. The CAP value was significantly correlated with the percentage of MaS on liver biopsy (r=0.635, P<0.001), and the median CAP value was significantly higher in subjects with MaS of >10% than in those with MaS of ≤10% (300 dB/m vs. 209 dB/m, P<0.001). The AUROC for diagnosing MaS of >10% by CAP was 0.938 (95% confidence interval, 0.896 to 0.967), and a CAP of >259 dB/m yielded a sensitivity of 84.2% and a specificity of 92.4%.

CONCLUSION

The CAP measured using TE was significantly correlated with MaS and accurately detected substantial MaS in potential living liver donors. The CAP is a promising tool for the noninvasive diagnosis of MaS and may be used to screen unsuitable living liver donor candidates.

Long-term outcomes of Roux-en-Y gastric bypass or sleeve gastrectomy in patients with cirrhosis; before, during or after liver transplantation: A single center's experience

BACKGROUND

The increasing prevalence of morbid obesity (MO) results in parallel growth of obesity-associated liver diseases necessitating liver transplantation (LT).

OBJECTIVE

To examine the feasibility and safety of Roux-en-Y gastric bypass or sleeve gastrectomy in the setting of LT.

METHODS

This retrospective chart review included the data on all the MO candidates before and after LT who underwent bariatric surgery (BS) in our institution between 04/2013-09/2016. The reported outcomes were weight change and early and late postoperative complications (mean follow-up: 43 ± 11.1 months).

RESULTS

Eighteen MO peri-LT patients (10 females, 8 males, average age 48 years) were included in the study. Ten had cirrhosis (mean Model of End-stage Liver Disease [MELD] score of 12.5 ± 6.42), three underwent concurrent LT and BS (mean MELD score 23.7 ± 0.58), and five had LT (mean of 56 months from LT). The mean percentage of total and excess weight loss was 31% and 81%, respectively. Six of the eight patients with type 2 diabetes mellitus became normoglycemic after BS. Three patients sustained perioperative complications. Two cirrhotic patients died 1 and 4.5 years after BS with decompensation.

CONCLUSIONS

Bariatric surgery appears to effectively address obesity in cirrhotic and LT patients. The surgical risk is higher than that of the regular BS population.

Non-alcoholic fatty liver and chronic kidney disease: Retrospect, introspect, and prospect

With the growing prevalence of obesity and diabetes in the United States and across the world, a rise in the overall incidence and prevalence of non-alcoholic fatty liver disease (NAFLD) is expected. The risk factors for NAFLD are also associated with the development of chronic kidney disease (CKD). We review the epidemiology, risk factors, genetics, implications of gut dysbiosis, and specific pathogenic mechanisms linking NAFLD to CKD. Mechanisms such as ectopic lipid accumulation, cellular signaling abnormalities, and the interplay between fructose consumption and uric acid accumulation have led to the emergence of potential therapeutic implications for this patient population. Transplant evaluation in the setting of both NAFLD and CKD is also reviewed. Potential strategies for surveillance and management include the monitoring of comorbidities, the use of non-invasive fibrosis scoring systems, and the measurement of laboratory markers. Lastly, we discuss the management of patients with NAFLD and CKD, from preventative measures to experimental interventions.

NAFLD and Infection, a Nuanced Relationship

The prevalence of nonalcoholic fatty liver disease (NAFLD) has increased significantly over the last few decades mirroring the increase in obesity and type II diabetes mellitus. NAFLD has become one of the most common indications for liver transplantation. The deleterious effects of NAFLD are not isolated to the liver only, for it has been recognized as a systemic disease affecting multiple organs through protracted low-grade inflammation mediated by the metabolic activity of excessive fat tissue. Extrahepatic manifestations of NAFLD such as cardiovascular disease, polycystic ovarian syndrome, chronic kidney disease, and hypothyroidism have been well described in the literature. In recent years, it has become evident that patients suffering from NAFLD might be at higher risk of developing various infections. The proposed mechanism for this association includes links through hyperglycemia, insulin resistance, alterations in innate immunity, obesity, and vitamin D deficiency. Additionally, a risk independent of these factors mediated by alterations in gut microbiota might contribute to a higher burden of infections in these individuals. In this narrative review, we synthetize current knowledge on several infections including urinary tract infection, pneumonia, Helicobacter pylori, coronavirus disease 2019, and Clostridioides difficile as they relate to NAFLD. Additionally, we explore NAFLD's association with hidradenitis suppurativa.

Human biomimetic liver microphysiology systems in drug development and precision medicine

Microphysiology systems (MPS), also called organs-on-chips and tissue chips, are miniaturized functional units of organs constructed with multiple cell types under a variety of physical and biochemical environmental cues that complement animal models as part of a new paradigm of drug discovery and development. Biomimetic human liver MPS have evolved from simpler 2D cell models, spheroids and organoids to address the increasing need to understand patient-specific mechanisms of complex and rare diseases, the response to therapeutic treatments, and the absorption, distribution, metabolism, excretion and toxicity of potential therapeutics. The parallel development and application of transdisciplinary technologies, including microfluidic devices, bioprinting, engineered matrix materials, defined physiological and pathophysiological media, patient-derived primary cells, and pluripotent stem cells as well as synthetic biology to engineer cell genes and functions, have created the potential to produce patient-specific, biomimetic MPS for detailed mechanistic studies. It is projected that success in the development and maturation of patient-derived MPS with known genotypes and fully matured adult phenotypes will lead to advanced applications in precision medicine. In this Review, we examine human biomimetic liver MPS that are designed to recapitulate the liver acinus structure and functions to enhance our knowledge of the mechanisms of disease progression and of the absorption, distribution, metabolism, excretion and toxicity of therapeutic candidates and drugs as well as to evaluate their mechanisms of action and their application in precision medicine and preclinical trials.

Small intestinal bacterial overgrowth and non-alcoholic fatty liver disease diagnosed by transient elastography and liver biopsy

BACKGROUND

We aimed to determine if there was a higher incidence of small intestinal bacterial overgrowth (SIBO) in non-alcoholic fatty liver disease (NAFLD) than in patients without NAFLD. Moreover, we assessed whether patients with significant fibrosis (SF) had a higher incidence of SIBO compared with patients with non-significant or no liver fibrosis.

METHODS

NAFLD was diagnosed in 117 patients by using Fibroscan with a controlled attenuation parameter (CAP) as well as liver biopsy (LB). SIBO was defined by esophagogastroduodenoscopy with an aspiration of the descending duodenum.

RESULTS

Patients with non-alcoholic steatohepatitis (NASH) and those with SF on LB had a significantly higher incidence of SIBO than patients without NASH and those without SF, respectively (P < .05). According to histological characteristics, there was a higher proportion of patients in the SIBO group with higher steatosis and fibrosis grade, lobular and portal inflammation, and ballooning grade (P < .001). In multivariate analysis, significant predictors associated with SF and NASH were type 2 diabetes mellitus (T2DM) and SIBO. Moreover, in multivariate analysis, significant predictors that were independently associated with SIBO were T2DM, fibrosis stage and ballooning grade (OR 8.80 (2.07-37.37), 2.50 (1.16-5.37) and 27.6 (6.41-119), respectively). The most commonly isolated were gram-negative bacteria, predominantly Escherichia coli and Klebsiella pneumoniae.

CONCLUSION

In this relatively large population of patients, we used a gold standard for both SIBO (quantitative culture of duodenum's descending part aspirate) and NAFLD (LB), and we demonstrated that NASH patients and those with SF had a higher incidence of SIBO. Moreover, significant predictors independently associated with SIBO were T2DM, fibrosis stage and ballooning grade. Although TE is a well-investigated method for steatosis and fibrosis detection, in our study, independent predictors of SIBO were histological characteristics of NAFLD, while elastographic parameters did not reach statistical significance.

Noninvasive markers of liver steatosis and fibrosis after liver transplantation - Where do we stand?

In the last two decades, advances in immunosuppressive regimens have led to fewer complications of acute rejection crisis and consequently improved short-term graft and patient survival. In parallel with this great success, long-term post-transplantation complications have become a focus of interest of doctors engaged in transplant medicine. Metabolic syndrome (MetS) and its individual components, namely, obesity, dyslipidemia, diabetes, and hypertension, often develop in the post-transplant setting and are associated with immuno-suppressive therapy. Nonalcoholic fatty liver disease (NAFLD) is closely related to MetS and its individual components and is the liver manifestation of MetS. Therefore, it is not surprising that MetS and its individual components are associated with recurrent or "de novo" NAFLD after liver transplantation (LT). Fibrosis of the graft is one of the main determinants of overall morbidity and mortality in the post-LT period. In the assessment of post-LT steatosis and fibrosis, we have biochemical markers, imaging methods and liver biopsy. Because of the significant economic burden of post-LT steatosis and fibrosis and its potential consequences, there is an unmet need for noninvasive methods that are efficient and cost-effective. Biochemical scores can overestimate fibrosis and are not a good method for fibrosis evaluation in liver transplant recipients due to frequent post-LT thrombocytopenia. Transient elastography with controlled attenuation parameter is a promising noninvasive method for steatosis and fibrosis. In this review, we will specifically focus on the evaluation of steatosis and fibrosis in the post-LT setting in the context of de novo or recurrent NAFLD.

The Role of Resveratrol in Liver Disease: A Comprehensive Review from In Vitro to Clinical Trials

Many studies have shown that resveratrol has a lot of therapeutic effects on liver disorders. Its administration can significantly increase the survival rate after liver transplantation, reduce fat deposition and ischemia-induced necrosis and apoptosis in Wistar rats. Resveratrol can provide Liver protection against chemical, cholestatic, and alcohol-mediated damage. It can improve glucose metabolism and lipid profile, reduce liver fibrosis, and steatosis. Additionally, it is capable of altering the fatty acid composition of the liver cells. Resveratrol may be a potential treatment option for the management of non-alcoholic fatty liver disease (NAFLD) due to its anti-inflammatory, antioxidant, and calorie-restricting effects. There are also studies that have evaluated the effect of resveratrol on lipid and liver enzyme profiles among patients with metabolic syndrome (MetS) and related disorders. Based on the extent of liver disease worldwide and the need to find new treatment possibilities, this review critically examines current in vitro and in vivo preclinical studies and human clinical studies related to liver protection.

Accuracy of Controlled Attenuation Parameter and Liver Stiffness Measurement in Patients with Non-alcoholic Fatty Liver Disease

We evaluated the diagnostic accuracy of the controlled attenuation parameter (CAP) and liver stiffness measurements (LSM) measured with either an M or XL probe against liver biopsy (LB) in patients with non-alcoholic fatty liver disease (NAFLD). This study was a cross-sectional prospective study that included 179 NAFLD patients. With a cutoff value for CAP ≥345, we can exclude significant steatosis in 87% (79.4%-92.5%) of our population. With respect to the LSM, the highest accuracy was obtained for F ≥ F3 (area under the receiver operating characteristic curve [AUROC] = 0.98) and F = F4 (AUROC = 0.98). In a multivariable linear regression model, significant predictors influencing LSM were fibrosis stage (β = 2.6, p < 0.001) as a positive predictor and lobular inflammation (β = -0.68, p = 0.04) as a negative predictor, without significant influence after adjustment for CAP and probe type. We found that CAP is a satisfactory method for excluding advanced steatosis, while LSM is a good non-invasive marker for the exclusion of fibrosis.

Treatments for NAFLD: State of Art

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

Oxidative Stress in Non-alcoholic Fatty Liver Disease. An Updated Mini Review

Non-alcoholic fatty liver disease (NAFLD) is a challenging disease caused by multiple factors, which may partly explain why it remains still orphan of an adequate therapeutic strategy. Herein we focus on the interplay between oxidative stress (OS) and the other causal pathogenetic factors. Different reactive oxygen species (ROS) generators contribute to NAFLD inflammatory and fibrotic progression, which is quite strictly linked to the lipotoxic liver injury from fatty acids and/or a wide variety of their biologically active metabolites in the context of either a two-hit or a (more recent) multiple parallel hits theory. An antioxidant defense system is usually able to protect hepatic cells from damaging effects caused by ROS, including those produced into the gastrointestinal tract, i.e., by-products generated by usual cellular metabolic processes, normal or dysbiotic microbiota, and/or diet through an enhanced gut–liver axis. Oxidative stress originating from the imbalance between ROS generation and antioxidant defenses is under the influence of individual genetic and epigenetic factors as well. Healthy diet and physical activity have been shown to be effective on NAFLD also with antioxidant mechanisms, but compliance to these lifestyles is very low. Among several considered antioxidants, vitamin E has been particularly studied; however, data are still contradictory. Some studies with natural polyphenols proposed for NAFLD prevention and treatment are encouraging. Probiotics, prebiotics, diet, or fecal microbiota transplantation represent new therapeutic approaches targeting the gut microbiota dysbiosis. In the near future, precision medicine taking into consideration genetic or environmental epigenetic risk factors will likely assist in further selecting the treatment that could work best for a specific patient.

Association between Gastroesophageal Reflux Disease and Elastographic Parameters of Liver Steatosis and Fibrosis: Controlled Attenuation Parameter and Liver Stiffness Measurements

AIM

Our aim was to investigate the association among elastographic parameters of liver steatosis and fibrosis, controlled attenuation parameter (CAP) and liver stiffness measurement (LSM), with gastroesophageal reflux disease (GERD).

METHODS

In this prospective, cross-sectional study, we have evaluated 937 patients with one or more components of the metabolic syndrome who had an esophagogastroduodenoscopy (EGD) due to GERD symptoms. In all patients, a laboratory analysis, an abdominal ultrasound, and FibroScan measurements were done. GERD was defined by EGD.

RESULTS

The mean body mass index (BMI) of the study population was 30.95 ± 5.45 kg/m². The prevalence of increased CAP was 82.6% (774/937). Patients with increased CAP were younger, were more obese, had higher prevalence of hypertension, diabetes, and dyslipidemia, and had higher values of aminotransferases. Similar results of higher prevalence in patients with elevated CAP were observed with GERD, hiatal hernia, and insufficient cardia (defined as deficient or absent closure of the gastric inlet in relation to the esophagus). Additionally, patients with elevated CAP had a higher prevalence of GERD grades B and C in comparison to those without elevated CAP. Consequently, patients who did not have elevated CAP had a higher prevalence of GERD grade A. Even though we have found an upward trend in the prevalence of GERD, hiatal hernia, and insufficient cardia, there was no significant difference between subjects with fibrosis (F) 1-2 and F3-4 stage of fibrosis or F1 and F2-4. In a binary logistic regression, a significant positive association with GERD was obtained for CAP. Furthermore, a significant positive association with hiatal hernia was obtained for BMI and CAP. Finally, a significant positive association with hiatal hernia was obtained with CAP in multivariate analysis.

CONCLUSION

To the best of our knowledge, our study is the first to reveal a positive association between CAP as a surrogate marker of liver steatosis and GERD after adjustments for other clinical variables.

Assessment of Steatosis and Fibrosis in Liver Transplant Recipients Using Controlled Attenuation Parameter and Liver Stiffness Measurements

AIM

The primary objective of this study was to evaluate the prevalence of increased controlled attenuation parameter (CAP) and liver stiffness measurements (LSM) as surrogate markers of liver steatosis and fibrosis in liver transplant recipient (LTR). Secondary objectives were to determine the predictors of increased CAP and LSM in population of LTR.

METHODS

In this prospective, cross-sectional study, we have evaluated 175 LTRs' mean age as 61 (53-65) with a functioning graft for more than one year who came for regular outpatient examinations to the Department of Gastroenterology, University Hospital (UH) Merkur, Zagreb, Croatia.

RESULTS

Of 175 analyzed LTRs, 34.28% had obesity, 64.00% had hypertension, 38.28% had diabetes, and 58.85% had hyperlipidemia. The prevalence of liver steatosis was 68.57%, while the prevalence of severe liver steatosis was 46.85%. On multivariate analysis, independent factors associated with liver steatosis were male gender, total cholesterol as positive predictor, and HDL as negative predictor, and independent factors positively associated with severe liver steatosis were higher body mass index (BMI) and higher triglyceride levels. The prevalence of moderate liver fibrosis was 54.85%, while the prevalence of advanced liver fibrosis was 24%. On multivariate analysis, independent factors positively associated with moderate fibrosis were gamma-glutamyl transferase (GGT) and CAP, while the independent factor positively associated with advanced fibrosis was GGT.

CONCLUSION

Our study showed high prevalence of increased CAP and LSM measurements as surrogate markers of liver steatosis and fibrosis. Metabolic syndrome components were highly present and were associated with CAP and LSM values as well as in the pretransplant setting. Due to high prevalence of metabolic comorbidities and nonalcoholic fatty liver disease in LTRs and the lack of the abnormal liver test in a significant number of these patients, TE with CAP may be a reasonable initial assessment for LTRs with one or more components of the metabolic syndrome.

Profiling the liver graft

PURPOSE OF REVIEW

Achieving operational tolerance remains a priority in liver transplantation. Although several biomarkers of tolerance and rejection have been identified, few have been reproducible and validated across centers, and therefore have yet to reach clinical practice. Here we summarize findings from prior seminal studies and review current developments in profiling the liver allograft.

RECENT FINDINGS

Substantial efforts and progress have been made in the recent years towards the discovery of reliable biomarkers that can predict and guide successful immunosuppression withdrawal. Recent studies have also investigated the transcriptomic signatures underlying not only acute rejection but also subclinical inflammation and chronic allograft injury.

SUMMARY

As new genomic and sequencing technologies continue to develop, clinical trials are underway to validate biomarkers of tolerance, as well as better understand the mechanisms of both acute and subclinical rejection, with the goal of maximizing allograft survival. Altogether, this will hopefully enable the implementation of immunosuppression withdrawal protocols into clinical practice and make operational tolerance reliably attainable in the near future.

LUM is the hub gene of advanced fibrosis in nonalcoholic fatty liver disease patients

INTRODUCTION

Advanced fibrosis in nonalcoholic fatty liver disease (NAFLD) is associated with a poor prognosis. The genetic factors contributing to fibrosis in NAFLD have been described. However, the genetic mechanism and hub genes of advanced fibrosis have not been elucidated to date. In this study, we performed a weighted gene coexpression network analysis (WGCNA) to identify the hub genes related to advanced fibrosis in NAFLD.

MATERIALS AND METHODS

The datasets GSE89632 and GSE31803 of NAFLD patients were selected from the Gene Expression Omnibus (GEO) database of NCBI and analyzed by WGCNA. The hub genes were selected in the GSE31803 dataset and verified in the GSE31803 dataset. Gene Ontology (GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of the dataset were also performed.

RESULTS

The gene LUM was identified as the hub gene in the datasets GSE89632 and GSE31803 according to three different algorithms (gene significance and module membership, the pathways of the genes, and protein expressed by the genes). The functional enrichment analysis shows that the identified module is related to the extracellular matrix, regulation of cell proliferation, and the inflammatory response. The metabolic pathway analysis identified metabolic pathways and focal adhesion as the most important pathways.

CONCLUSION

By a variety of methods, LUM was identified as the hub gene of advanced fibrosis in patients with NAFLD. Therefore, further research on the LUM gene is warranted.

Screening for nonalcoholic fatty liver disease in patients with type 2 diabetes mellitus using transient elastography - a prospective, cross sectional study

AIM

To investigate the prevalence and severity of nonalcoholic fatty liver disease (NAFLD) in patients with diabetes mellitus type 2 (T2DM), based on increased controlled attenuation parameter (CAP) and liver stiffness measurements obtained by transient elastography. In addition, we aimed to identify parameters that correlate with increased elastographic parameters of steatosis and fibrosis to provide a better indication when a patient with T2DM should be screened for NAFLD.

METHODS

We conducted prospective, cross-sectional study of 679 consecutive adult patients with diagnosed T2DM mean age 65.2±11.6. NAFLD was defined by transient elastography. In 105 patients a percutaneous liver biopsy (LB) was done.

RESULTS

The prevalence of NAFLD based on transient elastography was 83.6%. Independent factors associated with increased CAP were higher body mass index, longer T2DM duration, higher serum triglyceride, lower levels of vitamin D, higher C-reactive protein, and higher HOMA-IR. The prevalence of moderate liver fibrosis was 26.9% and advanced liver fibrosis 12.6%. Independent factors associated with moderated fibrosis based on elastography were higher body mass index and higher levels of alanine aminotransferase (ALT), while independent factors associated with advanced fibrosis were female gender, higher body mass index, higher levels of ALT, gama-glutamil transferase and C-reactive protein. Sixty-four (60.9%) of 105 patients with LB had NAFLD activity score ≥5. Regarding the presence and stages of fibrosis based on LB, moderate fibrosis was found in 29.5% of patients, while 29.5% had advanced fibrosis and 6.7% cirrhosis.

CONCLUSION

This study supports more aggressive screening for NAFLD and fibrosis in patients with T2DM.

Vitamin D for treatment of non-alcoholic fatty liver disease detected by transient elastography: A randomized, double-blind, placebo-controlled trial

AIM

To evaluate the effects of vitamin D on transient elastography (TE, FibroScan) indices of liver steatosis (controlled attenuation parameter [CAP]) and fibrosis (liver stiffness measurement [LSM]) in adults with non-alcoholic fatty liver disease (NAFLD).

PATIENTS AND METHODS

In this randomized (2:1), double-blind, single-centre, 12-month trial, patients with NAFLD were treated with vitamin D (1000 IU/day) (n = 201) or a matching placebo (n = 110). Two co-primary outcomes were changes in CAP and LSM after 360 days of treatment versus baseline. Two main secondary outcomes were CAP/LSM changes after 180 days of treatment.

RESULTS

Both CAP and LSM gradually decreased in vitamin D-treated patients and slightly increased in the placebo arm. Vitamin D was superior to placebo for both primary outcomes (mean differences in CAP and LSM changes (-49.5 dB/m [95% CI -59.5 to -39.4] and -0.72 kPa [95% CI -1.43 to 0.00], respectively) and both secondary outcomes (-22.1 dB/m [-32.1 to -12.1] and -0.89 kPa [-1.61 to -0.17], respectively). Of a number of exploratory outcomes (change at 12 months vs. baseline), vitamin D reduced serum uric acid (-17.9 μmol/L [-30.6 to -5.2]), gamma-glutamyltransferase (-8.9 IU/L [-15.5 to -2.3)] and fasting serum insulin levels (-5.1 pmol/L [-9.3 to -0.8]) as well as the homeostatic model assessment of insulin resistance index (-1.6 [-3.1 to -0.2]) (false discovery rate [5%]-adjusted P-values between .0572 and .0952).

CONCLUSION

Low-medium dose supplementation of vitamin D (1000 IU/day) over 12 months reduces TE indices of liver steatosis (CAP) and fibrosis (LSM) in NAFLD patients.