Correction to "Novel Antiproliferative Chimeric Compounds with Marked Histone Deacetylase Inhibitory Activity"

[This corrects the article DOI: 10.1021/ml5000959.].

The PD-1/PD-L1 Axis in the Biology of MASLD

Metabolic Dysfunction-Associated Steatotic Liver (MASL), previously named nonalcoholic fatty liver (NAFL), is a multifactorial disease in which metabolic, genetic, and environmental risk factors play a predominant role. Obesity and type 2 diabetes act as triggers of the inflammatory response, which contributes to the progression of MASL to Metabolic Dysfunction-Associated Steatohepatitis and the development of hepatocellular carcinoma. In the liver, several parenchymal, nonparenchymal, and immune cells maintain immunological homeostasis, and different regulatory pathways balance the activation of the innate and adaptative immune system. PD-1/PD-L1 signaling acts, in the maintenance of the balance between the immune responses and the tissue immune homeostasis, promoting self-tolerance through the modulation of activated T cells. Recently, PD-1 has received much attention for its roles in inducing an exhausted T cells phenotype, promoting the tumor escape from immune responses. Indeed, in MASLD, the excessive fat accumulation dysregulates the immune system, increasing cytotoxic lymphocytes and decreasing their cytolytic activity. In this context, T cells exacerbate liver damage and promote tumor progression. The aim of this review is to illustrate the main pathogenetic mechanisms by which the immune system promotes the progression of MASLD and the transition to HCC, as well as to discuss the possible therapeutic applications of PD-1/PD-L1 target therapy to activate T cells and reinvigorate immune surveillance against cancer.

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

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

SIRT5 rs12216101 T>G variant is associated with liver damage and mitochondrial dysfunction in patients with non-alcoholic fatty liver disease

BACKGROUND & AIMS

Sirtuin 5, encoded by the SIRT5 gene, is a NAD+-dependent deacylase that modulates mitochondrial metabolic processes through post-translational modifications. In this study, we aimed to examine the impact of the SIRT5 rs12216101 T>G non-coding single nucleotide polymorphism on disease severity in patients with non-alcoholic fatty liver disease (NAFLD).

METHODS

The rs12216101 variant was genotyped in 2,606 consecutive European patients with biopsy-proven NAFLD. Transcriptomic analysis, expression of mitochondrial complexes and oxidative stress levels were measured in liver samples from a subset of bariatric patients. Effects of SIRT5 pharmacological inhibition were evaluated in HepG2 cells exposed to excess free fatty acids. Mitochondrial energetics in vitro were investigated by high-performance liquid chromatography.

RESULTS

In the whole cohort, the frequency distribution of SIRT5 rs12216101 TT, TG and GG genotypes was 47.0%, 42.3% and 10.7%, respectively. At multivariate logistic regression analysis adjusted for sex, age >50 years, diabetes, and PNPLA3 rs738409 status, the SIRT5 rs12216101 T>G variant was associated with the presence of non-alcoholic steatohepatitis (odds ratio 1.20, 95% CI 1.03-1.40) and F2-F4 fibrosis (odds ratio 1.18; 95% CI 1.00-1.37). Transcriptomic analysis showed that the SIRT5 rs12216101 T>G variant was associated with upregulation of transcripts involved in mitochondrial metabolic pathways, including the oxidative phosphorylation system. In patients carrying the G allele, western blot analysis confirmed an upregulation of oxidative phosphorylation complexes III, IV, V and consistently higher levels of reactive oxygen species, reactive nitrogen species and malondialdehyde, and lower ATP levels. Administration of a pharmacological SIRT5 inhibitor preserved mitochondrial energetic homeostasis in HepG2 cells, as evidenced by restored ATP/ADP, NAD+/NADH, NADP+/NADPH ratios and glutathione levels.

CONCLUSIONS

The SIRT5 rs12216101 T>G variant, heightening SIRT5 activity, is associated with liver damage, mitochondrial dysfunction, and oxidative stress in patients with NAFLD.

IMPACT AND IMPLICATIONS

In this study we discovered that the SIRT5 rs12216101 T>G variant is associated with higher disease severity in patients with non-alcoholic fatty liver disease (NAFLD). This risk variant leads to a SIRT5 gain-of-function, enhancing mitochondrial oxidative phosphorylation and thus leading to oxidative stress. SIRT5 may represent a novel disease modulator in NAFLD.

Red and golden tomato administration improves fat diet-induced hepatic steatosis in rats by modulating HNF4α, Lepr, and GK expression

Introduction

Nonalcoholic fatty liver disease (NAFLD), characterized by lipid accumulation within hepatocytes exceeding 5% of liver weight, is strongly related to metabolic disorders, obesity, and diabetes and represents a health emergency worldwide. There is no standard therapy available for NAFLD. Lifestyle intervention, including phytonutrient intake, is key in preventing NAFLD development and progression.

Methods

We used a rat model of NAFLD to evaluate the effect of dietary supplementation with red tomato (RT) and golden tomato (GT)-a patented mix of fruit with varying degrees of ripeness and particularly rich in naringenin and chlorogenic acid-after steatosis development. We assessed the effects on body weight, metabolic profile, and hepatic steatosis.

Results and discussion

We found a correlation between the amelioration of all the parameters and the liver gene expression. Our results showed that, together with the reversion of steatosis, the consumption of RT and GT can cause a significant reduction in triglycerides, low-density lipoprotein-cholesterol, fasting glucose, and homeostasis model assessment index. Meanwhile, we observed an increase in high-density lipoprotein-cholesterol according to the amelioration of the general lipidic profile. Regarding hepatic gene expression, we found the upregulation of Gk and Hnf4α involved in metabolic homeostasis, Lepr involved in adipokine signaling, and Il6 and Tnf involved in inflammatory response. Taken together, our results suggest that dietary intake of red and golden tomatoes, as a nutraceutical approach, has potential in preventing and therapeutics of NAFLD.

Programmed cell death 1 genetic variant and liver damage in nonalcoholic fatty liver disease

BACKGROUND AND AIMS

Programmed cell death 1/programmed cell death-ligand 1 (PD-1/PDL-1) axis has been reported to modulate liver inflammation and progression to hepatocellular carcinoma (HCC) in patients with nonalcoholic fatty liver disease (NAFLD). Here, we examined whether the PDCD1 variation is associated with NAFLD severity in individuals with liver biopsy.

METHODS

We examined the impact of PDCD1 gene variants on HCC, as robust severe liver disease phenotype in UK Biobank participants. The strongest genetic association with the rs13023138 G>C variation was subsequently tested for association with liver damage in 2889 individuals who underwent liver biopsy for suspected nonalcoholic steatohepatitis (NASH). Hepatic transcriptome was examined by RNA-Seq in a subset of NAFLD individuals (n = 121). Transcriptomic and deconvolution analyses were performed to identify biological pathways modulated by the risk allele.

RESULTS

The rs13023138 C>G showed the most robust association with HCC in UK Biobank (p = 5.28E-4, OR = 1.32, 95% CI [1.1, 1.5]). In the liver biopsy cohort, rs13023138 G allele was independently associated with severe steatosis (OR 1.17, 95% CI 1.02-1.34; p = .01), NASH (OR 1.22, 95% CI 1.09-1.37; p < .001) and advanced fibrosis (OR 1.26, 95% CI 1.06-1.50; p = .007). At deconvolution analysis, rs13023138 G>C allele was linked to higher hepatic representation of M1 macrophages, paralleled by upregulation of pathways related to inflammation and higher expression of CXCR6.

CONCLUSIONS

The PDCD1 rs13023138 G allele was associated with HCC development in the general population and with liver disease severity in patients at high risk of NASH.

Metabolic memory in diabetic foot syndrome (DFS): MICRO-RNAS, single nucleotide polymorphisms (SNPs) frequency and their relationship with indices of endothelial function and adipo-inflammatory dysfunction

BACKGROUND

Diabetic foot is a significant cause of morbidity in diabetic patients, with a rate that is approximately twice that of patients without foot ulcers. "Metabolic memory" represents the epigenetic changes induced by chronic hyperglycaemia, despite the correction of the glucose levels themselves. These epigenetic modifications appear to perpetuate the damage caused by persistently elevated glucose levels even in their absence, acting at various levels, mostly affecting the molecular processes of diabetic ulcer healing.

METHODS

The aim of our cross-sectional study was to analyse a cohort of patients with diabetes with and without lower limb ulcers. We examined the effects of epigenetic changes on miRNA 126, 305, and 217 expression and the frequency of the SNPs of genes encoding inflammatory molecules (e.g., IL-6 and TNF-alpha) and their correlations with serum levels of proangiogenic molecules (e.g., ENOS, VEGF and HIF-1alpha) and several adipokines as well as with endothelial dysfunction, assessed noninvasively by reactive hyperaemia peripheral artery tonometry. Between March 2021 and June 2022, 110 patients were enrolled into the study: 50 diabetic patients with diabetic foot injuries, 40 diabetic patients without ulcerative complications and 20 nondiabetic patients as the control group.

RESULTS

Diabetic subjects with lower limb ulcerative lesions exhibited higher levels of inflammatory cytokines, such as VEGF (191.40 ± 200 pg/mL vs. 98.27 ± 56.92 pg/mL vs. 71.01 ± 52.96 pg/mL; p = 0.22), HIF-1alpha (40.18 ± 10.80 ng/mL vs. 33.50 ± 6.16 ng/mL vs. 33.85 ± 6.84 ng/mL; p = 0.10), and Gremlin-1 (1.72 ± 0.512 ng/mL vs. 1.31 ± 0.21 ng/mL vs. 1.11 ± 0.19 ng/mL; p < 0.0005), than those without lower limb ulcers and healthy controls. Furthermore, we observed that miR-217-5p and miR-503-5p were 2.19-fold (p < 0.05) and 6.21-fold (p = 0.001) more highly expressed in diabetic foot patients than in healthy controls, respectively. Additionally, diabetic patients without lower limb ulcerative complications showed 2.41-fold (p = 0) and 2.24-fold (p = 0.029) higher expression of miR-217-5p and miR-503-5p, respectively, than healthy controls. Finally, diabetic patients with and without ulcerative complications of the lower limbs showed higher expression of the VEGFC2578A CC polymorphism (p = 0.001) and lower expression of the VEGFC2578A AC polymorphism (p < 0.005) than the healthy control population. We observed a significant increase in Gremlin-1 levels in patients with diabetic foot, suggesting that this inflammatory adipokine may serve as a predictive marker for the diagnosis of diabetic foot.

CONCLUSIONS

Our results highlighted that patients with diabetic foot showed predominant expression of the VEGF C2578A CC polymorphism and reduced expression of the AC allele. Additionally, we found an overexpression of miR-217-5p and miR-503-5p in diabetic patients with and without diabetic foot syndrome compared with healthy controls. These results align with those reported in the literature, in which the overexpression of miR-217-5p and miR-503-5p in the context of diabetic foot is reported. The identification of these epigenetic modifications could therefore be helpful in the early diagnosis of diabetic foot and the treatment of risk factors. However, further studies are necessary to confirm this hypothesis.

MAFLD: a multisystem disease

Nonalcoholic fatty liver disease (NAFLD), affecting about 25% of general population and more than 50% of dysmetabolic patients, is an emerging cause of chronic liver disease and its complications. Recently, an international consensus of experts proposed to rename this disease as 'Metabolic dysfunction-Associated Fatty Liver Disease' (MAFLD) to focus on the bidirectional interplay between fatty liver and metabolic alterations and to stress the need of assessing fatty liver independently from alcohol consumption and other coexisting causes of liver disease. The peculiarity of NAFLD/MAFLD lies in the presence of a higher risk of not only - as expected - liver-related events but also of extrahepatic events, mostly cardiovascular and cancers. Available evidence suggests that these associations are not only the expression of sharing the same risk factors but shed light about the ability of NAFLD/MAFLD and particularly of its progressive form - nonalcoholic/metabolic dysfunction-associated steatohepatitis - to act as an independent risk factor via promotion of atherogenic dyslipidemia and a proinflammatory, profibrogenic, and procoagulant systemic environment. The present review summarizes available epidemiological and clinical evidence supporting the concept of NAFLD/MAFLD as a multisystemic disease, and highlights potential explanatory mechanisms underlying the association between NAFLD/MAFLD and extrahepatic disorders.

Mer Tyrosine Kinase (MERTK) modulates liver fibrosis progression and hepatocellular carcinoma development

MerTK is a tyrosine kinase receptor that belongs to the TAM (Tyro3/Axl/Mer) receptor family. It is involved in different processes including cellular proliferation/survival, cellular adhesion/migration, and release of the inflammatory/anti-inflammatory cytokines. Although it is reported that MERTK polymorphisms affect the severity of viral and metabolic liver diseases, being able to influence fibrosis progression and hepatocellular carcinoma development, the mechanisms remain unknown. Methods: using a microarray approach, we evaluated the liver expression of genes involved in fibrogenesis and hepatocarcinogenesis in patient with chronic hepatitis C (CHC), stratified for MERTK genotype and MERTK expression. Results: we found that the rs 4374383 AA homozygosity is associated with lower MERTK expression in CHC patients and that, depending on MERTK genotype, Matrix Metallopeptidase 9 (MMP9), Matrix Metallopeptidase 7 (MMP7), Secreted Frizzled Related Protein 1 (SFRP1) and WNT gene family 11(WNT11) show differential expression in patients with CHC with or without neoplastic progression. Conclusions: our results confirm that MERTK represents a genetic biomarker for progression of liver disease and are suggestive of translational relevance for the study of downstream pathways involved in fibrogenesis and hepatocarcinogenesis.

A cholestatic pattern predicts major liver-related outcomes in patients with non-alcoholic fatty liver disease

BACKGROUND & AIMS

NAFLD patients usually have an increase in AST/ALT levels, but cholestasis can also be observed. We aimed to assess in subjects with NAFLD the impact of the (cholestatic) C pattern on the likelihood of developing major liver-related outcomes (MALO).

METHODS

Five hundred and eighty-two consecutive patients with biopsy-proven NAFLD or a clinical diagnosis of NAFLD-related compensated cirrhosis were classified as hepatocellular (H), C and mixed (M) patterns, by using the formula (ALT/ALT Upper Limit of Normal-ULN)/(ALP/ALP ULN). MALO were recorded during follow-up. An external cohort of 1281 biopsy-proven NAFLD patients was enrolled as validation set.

RESULTS

H, M and C patterns were found in 153 (26.3%), 272 (46.7%) and 157 (27%) patients respectively. During a median follow-up of 78 months, only 1 (0.6%) patient with H pattern experienced MALO, whilst 15 (5.5%) and 38 (24.2%) patients in M and C groups had MALO. At multivariate Cox regression analysis, age >55 years (HR 2.55, 95% CI 1.17-5.54; p = .01), platelets <150 000/mmc (HR 0.14, 95% CI 0.06-0.32; p < .001), albumin <4 g/L(HR 0.62, 95% CI 0.35-1.08; p = .09), C versus M pattern (HR 7.86, 95% CI 1.03-60.1; p = .04), C versus H pattern(HR 12.1, 95% CI 1.61-90.9; p = .01) and fibrosis F3-F4(HR 35.8, 95% CI 4.65-275.2; p < .001) were independent risk factors for MALO occurrence. C versus M pattern(HR 14.3, 95% CI 1.90-105.6; p = .008) and C versus H pattern (HR 15.6, 95% CI 2.10-115.1; p = .0068) were confirmed independently associated with MALO occurrence in the validation set. The immunohistochemical analysis found a significantly higher prevalence of moderate-high-grade ductular metaplasia combined with low-grade ductular proliferation in C pattern when compared with the biochemical H pattern. Gene expression analysis showed a lower expression of NR1H3, RXRα and VCAM1 in patients with the C pattern.

CONCLUSIONS

The presence of a cholestatic pattern in patients with NAFLD predicts a higher risk of MALO independently from other features of liver disease.

A Genetic and Metabolic Staging System for Predicting the Outcome of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is an emerging cause of liver-related events (LREs). Here, we have assessed the ability of a composite score based on clinical features, metabolic comorbidities, and genetic variants to predict LREs. A total of 546 consecutive patients with NAFLD were recruited and stratified according to the fibrosis-4 (FIB-4) index. LREs were defined as occurrence of hepatocellular carcinoma or hepatic decompensation. Cox regression multivariate analysis was used to identify baseline variables associated with LREs. The UK Biobank was used as the validation cohort, and severe liver disease (incidence of cirrhosis, decompensated liver disease, hepatocellular carcinoma, and/or liver transplantation) was used as the outcome. LREs were experienced by 58 patients, only one of whom was in the cohort of patients with a FIB-4 score < 1.3. Multivariate Cox regression analysis of 229 patients with a FIB-4 score ≥ 1.3 highlighted clinical variables independently associated with the development of LREs, including older age, low platelet count, low albumin, low high-density lipoprotein cholesterol, certain genetic factors, and interactions between genetic factors and sex or diabetes. The area under the curve (AUC) for the model was 0.87 at 1, 3, and 5 years. Our novel Genetic and Metabolic Staging (GEMS) scoring system was derived from the Cox model linear predictor, ranked from 0 to 10, and categorized into five classes (0-5, 5-6, 6-7, 7-8, and 8-10). The risk of LREs increased from 4% in patients in the best class (GEMS score 0-5) to 91% in the worst (GEMS score 8-10). GEMS score was associated with incident severe liver disease in the study population (hazard ratio, 1.56; 95% confidence interval, 1.48-1.65; P < 0.001) as well as in the UK Biobank cohort where AUCs for prediction of severe liver disease at 1, 3, and 5 years were 0.70, 0.69, and 0.67, respectively. Conclusion: The novel GEMS scoring system has an adequate ability to predict the outcome of patients with NAFLD.

PSD3 downregulation confers protection against fatty liver disease

Fatty liver disease (FLD) is a growing health issue with burdening unmet clinical needs. FLD has a genetic component but, despite the common variants already identified, there is still a missing heritability component. Using a candidate gene approach, we identify a locus (rs71519934) at the Pleckstrin and Sec7 domain-containing 3 (PSD3) gene resulting in a leucine to threonine substitution at position 186 of the protein (L186T) that reduces susceptibility to the entire spectrum of FLD in individuals at risk. PSD3 downregulation by short interfering RNA reduces intracellular lipid content in primary human hepatocytes cultured in two and three dimensions, and in human and rodent hepatoma cells. Consistent with this, Psd3 downregulation by antisense oligonucleotides in vivo protects against FLD in mice fed a non-alcoholic steatohepatitis-inducing diet. Thus, translating these results to humans, PSD3 downregulation might be a future therapeutic option for treating FLD.

NR1H4 rs35724 G>C variant modulates liver damage in nonalcoholic fatty liver disease

BACKGROUND AND AIMS

Farnesoid X receptor (FXR) plays a key role in bile acid and lipid homeostasis. Experimental evidence suggests that it can modulate liver damage related to nonalcoholic fatty liver disease (NAFLD). We examined the impact of the NR1H4 rs35724 G>C, encoding for FXR, on liver damage in a large cohort of patients at risk of steatohepatitis.

METHODS

We considered 2,660 consecutive individuals at risk of steatohepatitis with liver histology. The rs35724 G>C polymorphisms were genotyped by TaqMan assays. Gene expression was evaluated by RNASeq in a subset of patients (n = 124).

RESULTS

The NR1H4 rs35724 CC genotype, after adjusting for clinic-metabolic and genetic confounders and for enrolling centre, was protective against severity of steatosis (GG vs CC OR 0.77, 95% CI 0.62-0.95; P = .01), steatohepatitis (GG vs CC OR 0.62, 95% CI 0.47-0.83; P = .001) and severity of fibrosis (GG vs CC OR 0.83, 95% CI 0.67-0.98; P = .04). The C allele was associated with higher total circulating cholesterol (P = .01). Patients carrying the NR1H4 rs35724 C allele had significantly higher hepatic mRNA levels of FXR and were associated with higher hepatic FGFR4 and Cyp39A1 that are in turn involved in bile acid synthesis.

CONCLUSIONS

Increased hepatic FXR expression due to the NR1H4 rs35724 C allele is linked to higher serum cholesterol but protects against steatosis, steatohepatitis and liver fibrosis. The translational relevance of these results for patient risk stratification and FXR-targeted therapy warrants further investigation.

PNPLA3 rs738409 C>G Variant Predicts Fibrosis Progression by Noninvasive Tools in Nonalcoholic Fatty Liver Disease

Liver fibrosis is the main predictor of events in patients with nonalcoholic fatty liver disease (NAFLD),¹ and its evolution is characterized by a nonlinear trend^2,3 mostly affected by metabolic risk factors, severity of liver inflammation and steatosis, and weight loss.³ The rs738409 C>G common variant in PNPLA3 gene has been associated with severity of fibrosis and risk of liver-related events in NAFLD.^4,5 Noninvasive tests as Fibrosis-4 (FIB-4) and liver stiffness measurement (LSM) are useful to rule-out advanced fibrosis and they could be reliable to predict fibrosis progression.^2,6 We aimed to evaluate in patients with NAFLD whether PNPLA3 rs738409 C>G variant impacts on fibrosis progression, noninvasively assessed by FIB-4 and LSM.

Coffee Restores Expression of lncRNAs Involved in Steatosis and Fibrosis in a Mouse Model of NAFLD

Background and aim: Coffee intake exerts protective effects against non-alcoholic fatty liver disease (NAFLD), although without fully cleared mechanisms. In this study we aimed to assess whether coffee consumption may influence the expression of long non-coding RNAs (lncRNAs) in the liver. Methods: C57BL/6J mice were fed a 12-week standard diet (SD), high-fat diet (HFD) or HFD plus decaffeinated coffee solution (HFD + coffee). Expression of specific lncRNAs involved in NAFLD was analyzed by real-time PCR. For the most differentially expressed lncRNAs, the analysis was also extended to their mRNA targets. Results: Decaffeinated coffee intake reduced body weight gain, prevented NAFLD, lowered hyperglycemia and hypercholesterolemia. NAFLD was associated with lower hepatic expression of Gm16551, a lncRNA inhibiting de novo lipogenesis, and higher expression of H19, a lncRNA promoting fibrogenesis. Coffee intake restored Gm16551 to levels observed in lean mice and downregulated gene expression of its targets acetyl coenzyme A carboxylase 1 and stearoyl coenzyme A desaturase 1. Furthermore, coffee consumption markedly decreased hepatic expression of H19 and of its target gene collagen alpha-1(I) chain; consistently, in mice fed HFD + coffee liver expression of αSMA protein returned to levels of mice fed SD. Expression of lncRNA involved in circadian clock such as fatty liver-related lncRNA 1 (FLRL1) and fatty liver-related lncRNA 2 (FLRL2) were upregulated by HFD and were also modulated by coffee intake. Conclusion. Hepatoprotective effects of coffee may be depending on the modulation of lncRNAs involved in key pathways of NAFLD onset and progression.

PNPLA3 and TLL-1 Polymorphisms as Potential Predictors of Disease Severity in Patients With COVID-19

Albeit the pathogenesis of COVID-19 remains unclear, host's genetic polymorphisms in genes involved in infection and reinfection, inflammation, or immune stimulation could play a role in determining the course and outcome. We studied in the early phase of pandemic consecutive patients (N = 383) with SARS-CoV-2 infection, whose subsequent clinical course was classified as mild or severe, the latter being characterized by admission to intensive therapy unit or death. Five host gene polymorphisms (MERTK rs4374383, PNPLA3 rs738409, TLL-1 rs17047200, IFNL3 rs1297860, and INFL4 rs368234815) were assessed by using whole nucleic acids extracted from nasopharyngeal swabs. Specific protease cleavage sites of TLL-1 on the SARS-CoV-2 Spike protein were predicted in silico. Male subjects and older patients were significantly at higher risk for a severe outcome (p = 0.02 and p < 0.001, respectively). By considering patients ≤65 years, after adjusting for potential confounding due to sex, an increased risk of severe outcome was found in subjects with the GG genotype of PNPLA3 (adj-OR: 4.69; 95% CI = 1.01-22.04) or TT genotype of TLL-1 (adj-OR=9.1; 95% CI = 1.45-57.3). In silico evaluation showed that TLL-1 is potentially involved in the Spike protein cleavage which is essential for viral binding and entry into the host cells using the host receptor angiotensin-converting enzyme 2 (ACE2). Subjects carrying a GG genotype in PNPLA3 gene might have a constitutive upregulation of the NLRP3 inflammasome and be more prone to tissue damage when infected by SARS-CoV-2. The TT genotype in TLL-1 gene might affect its protease activity on the SARS-CoV-2 Spike protein, enhancing the ability to infect or re-infect host's cells. The untoward effect of these variants on disease course is evident in younger patients due to the relative absence of comorbidities as determinants of prognosis. In the unresolved pathogenetic scenery of COVID-19, the identification of genetic variants associates with more prolonged course or with a severe outcome of infection would support the development of predictive tools useful to stratify subjects by risk class at presentation. Moreover, the individuation of key genes could contribute to a better understanding of the pathways involved in the pathogenesis, giving the basis for rational therapeutic approaches.

Phylogenetic analysis in the clinical risk management of an outbreak of hepatitis C virus infection among transfused thalassaemia patients in Italy

BACKGROUND

Occurrence of hepatitis C virus (HCV) infection is reduced by effective risk management procedures, but patient-to-patient transmission continues to be reported in healthcare settings.

AIM

To report the use of phylogenetic analysis in the clinical risk management of an HCV outbreak among 128 thalassaemia outpatients followed at a thalassaemia centre of an Italian hospital.

METHODS

Epidemiological investigation and root-cause analysis were performed. All patients with acute hepatitis and known chronic infection were tested for HCV RNA, HCV genotyping, and NS3, NS5A, and NS5B HCV genomic region sequencing. To identify transmission clusters, phylogenetic trees were built for each gene employing Bayesian methods.

FINDINGS

All patients with acute hepatitis were infected with HCV genotype 1b. Root-cause analysis, including a lookback procedure, excluded blood donors as the source of HCV transmission. The phylogenetic analysis, conducted on seven patients with acute infection and eight patients with chronic infection, highlighted four transmission clusters including at least one patient with chronic and one patient with acute HCV infection. All patients in the same cluster received a blood transfusion during the same day. Two patients with acute hepatitis spontaneously cleared HCV within four weeks and nine patients received ledipasvir plus sofosbuvir for six weeks, all achieving a sustained virological response.

CONCLUSION

Combined use of root-cause analysis and molecular epidemiology was effective in ascertaining the origin of the HCV outbreak. Antiviral therapy avoided the chronic progression of the infection and further spread in care units and in the family environment.

PCSK9 rs11591147 R46L loss-of-function variant protects against liver damage in individuals with NAFLD

BACKGROUND AND AIMS

The proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a key role in cholesterol homeostasis, and its inhibition represents an effective therapy to lower low-density lipoprotein cholesterol (LDL-C) levels. In this study, we examined the impact of the PCSK9 rs11591147 loss-of-function (LOF) variant on liver damage in a multicenter collection of patients at risk of nonalcoholic steatohepatitis (NASH), in clinical samples and experimental models.

METHODS

We considered 1874 consecutive individuals at risk of NASH as determined by histology. The SNP rs11591147, encoding for the p.R46L variant of PCSK9, was genotyped by TaqMan assays. We also evaluated 1) PCSK9 mRNA hepatic expression in human liver, and 2) the impact of a NASH-inducing diet in mice with hepatic overexpression of human PCSK9.

RESULTS

Carriers of PCSK9 rs11591147 had lower circulating LDL-C levels and were protected against nonalcoholic fatty liver disease (NAFLD) (OR: 0.42; 95% CI: 0.22-0.81; P = .01), NASH (OR: 0.48; 95% CI: 0.26-0.87; P = .01) and more severe fibrosis (OR: 0.55; 95% CI: 0.32-0.94; P = .03) independently of clinical, metabolic and genetic confounding factors. PCSK9 hepatic expression was directly correlated with liver steatosis (P = .03). Finally, liver-specific overexpression of human PCSK9 in male mice drives NAFLD and fibrosis upon a dietary challenge.

CONCLUSIONS

In individuals at risk of NASH, PCSK9 was induced with hepatic fat accumulation and PCSK9 rs11591147 LOF variant was protective against liver steatosis, NASH and fibrosis, suggesting that PCSK9 inhibition may be a new therapeutic strategy to treat NASH.

Hepatitis C virus eradication by direct antiviral agents abates oxidative stress in patients with advanced liver fibrosis

BACKGROUND AND AIMS

HCV eradication improves non-hepatic outcomes such as cardiovascular diseases, although without clearly defined mechanisms. In this study we aimed to assess whether improvement of carotid atherosclerosis may be linked to a reduction in systemic oxidative stress after viral clearance.

METHODS

We studied a retrospective cohort of 105 patients (age 62.4 ± 11.2 years; 62 men) with F3/F4 fibrosis, characterized by carotid ultrasonography at baseline and at sustained virologic response (SVR) follow-up. Levels of 8-iso-prostaglandin F_2α (F₂ -isoprostanes) and other oxidative stress markers were measured on frozen sera. Association between change (denoted as Δ) in oxidative stress markers (exposures) and change in carotid intima-media thickness (cIMT) (outcome) was examined using multiple linear regression.

RESULTS

Subclinical atherosclerosis, defined as the presence of carotid plaque and/or cIMT ≥ 0.9, was present in 72% of the cohort. All patients achieved SVR that led to reduction in cIMT (0.92 ± 0.20 vs 0.83 ± 0.21 mm, P < .001). HCV eradication markedly decreased serum levels of F₂ -isoprostanes (620.5 [143.2; 1904.1] vs 119.51 [63.2; 400.6] pg/mL, P < .0001), lipid hydroperoxides (13.8 [6.3; 20.7] vs 4.9 [2.3; 9.6] nmol/μl, P < .0001) and 8-hydroxy-2'-deoxyguanosine (558.9 [321.0; 6301.2] vs 294.51 [215.31; 408.95] pg/mL, P < .0001), whereas increased serum GPx activity (10.44 [4.6; 16.3] vs 13.75 [9.42; 20.63] nmol/min/mL, P = .001). By multiple linear regression analysis ΔcIMT was independently associated with ΔF₂ -isoprostanes (β: 1.746 [0.948; 2.543]; P < .0001) after adjustment for age, baseline F₂ -isoprostanes and baseline IMT.

CONCLUSIONS

Besides association of lipid peroxidation with severity of liver disease, the reduction in F₂ -isoprostanes may be involved in the improvement of atherosclerosis after HCV eradication.

SARS-CoV-2 Viral Load, IFNλ Polymorphisms and the Course of COVID-19: An Observational Study

The course of SARS-CoV-2 infection ranges from asymptomatic to a multiorgan disease. In this observational study, we investigated SARS-CoV-2 infected subjects with defined outcomes, evaluating the relationship between viral load and single nucleotide polymorphisms of genes codifying for IFNλs (interferon). The study enrolled 381 patients with laboratory-confirmed SARS-CoV-2 infection. For each patient, a standardized form was filled including sociodemographic variables and clinical outcomes. The host's gene polymorphisms (IFNL3 rs1297860 C/T and INFL4 rs368234815 TT/ΔG) and RtReal-Time PCR cycle threshold (PCR Ct) value on SARS-CoV-2 were assessed on nasal, pharyngeal or nasopharyngeal swabs. Higher viral loads were found in patients aged > 74 years and homozygous mutant polymorphisms DG in IFNL4 (adj-OR = 1.16, 95% CI = 1.01-1.34 and adj-OR = 1.24, 95% CI = 1.09-1.40, respectively). After adjusting for age and sex, a statistically significantly lower risk of hospitalization was observed in subjects with higher RtReal-Time PCR cycle threshold values (adj-OR = 0.95, 95% CI = 0.91, 0.99; p = 0.028). Our data support the correlation between SARS-CoV-2 load and disease severity, and suggest that IFNλ polymorphisms could affect the ability of the host to modulate viral infection without a clear impact on the outcome of COVID-19.

Optimizing Sequential Systemic Therapies for Advanced Hepatocellular Carcinoma: A Decision Analysis

Background: An optimal sequential systemic therapy for advanced hepatocellular carcinoma (HCC) has not been discovered. We developed a decision model based on available clinical trials to identify an optimal risk/benefit strategy for sequences of novel systemic agents. Methods: A Markov model was built to simulate overall survival (OS) among patients with advanced HCC. Three first-line (single-agent Sorafenib or Lenvatinib, and combination of Atezolizumab plus Bevacizumab) followed by five second-line treatments (Regorafenib, Cabozantinib, Ramucirumab, Nivolumab, Pembrolizumab) were compared in fifteen sequential strategies. The likelihood of transition between states (initial treatment, cancer progression, death) was derived from clinical trials. Life-year gained (LYG) was the main outcome. Rates of severe adverse events (SAEs) (≥grade 3) were calculated. The innovative measure, called incremental safety-effectiveness ratio (ISER), of the two best sequential treatments was calculated as the difference in probability of SAEs divided by LYG. Results: Lenvatinib followed by Nivolumab (median OS, 27 months) was the most effective sequence, producing a LYG of 0.75, while Atezolizumab plus Bevacizumab followed by Nivolumab was the safest sequence (SAEs 40%). Accordingly, the net health benefit assessed by ISER favored Lenvatinib followed by Nivolumab, compared to Atezolizumab plus Bevacizumab, followed by Nivolumab in 52% of cases. Conclusion: Further sequential clinical trials or large-scale real-world studies may prove useful to evaluate the net health benefit of the best sequential treatment for advanced HCC.

Neurotensin up-regulation is associated with advanced fibrosis and hepatocellular carcinoma in patients with MAFLD

BACKGROUND & AIMS

Neurotensin (NTS), a 13-aminoacid peptide localized in central nervous system and gastrointestinal tract, is involved in lipid metabolism and promotes various cancers onset mainly by binding to neurotensin receptor 1 (NTSR1). Increased plasma levels of pro-NTS, the stable NTS precursor, have been associated with type 2 diabetes (T2D), cardiovascular diseases and metabolic associated fatty liver disease (MAFLD). We aimed to evaluate 1) the impact of NTS rs1800832 and NTSR1 rs6090453 genetic variants on liver damage in 1166 MAFLD European individuals, 2) the relation between NTS variant and circulating pro-NTS and 3) the hepatic NTS expression by RNAseq transcriptomic analysis in 125 bariatric patients.

RESULTS

The NTS rs1800832 G allele was associated with hepatic fibrosis (OR 1.27, 95% confidence interval (CI). 1.02-1.58; p = 0.03), even more in carriers of both NTS and NTSR1 G risk alleles (OR 1.17, 95% CI. 1.03-1.34; p = 0.01), with cirrhosis (OR 1.58, 95% CI. 1.07-2.34; p = 0.02) and HCC (OR 1.98, 95% CI. 1.24-3.2; p = 0.004). Pro-NTS circulating levels were correlated with T2D (p = 0.005), BMI, (p = 0.04), age (p = 0.0016), lobular inflammation (p = 0.0025), fibrosis>2 (p < 0.0001), cirrhosis (p = 0.0009) and HCC (p < 0.0001) and more so after stratification for the NTS G allele. Transcriptomic data showed that hepatic NTS expression correlated with that of fibrogenic genes (p < 0.05).

CONCLUSIONS

NTS rs1800832 variant is associated with advanced fibrosis and HCC in MAFLD patients likely affecting NTS protein activity. The rs6090453 NTSR1 gene variant synergizes with NTS rs1800832 mutation to promote liver damage. Prospective studies are necessary to confirm NTS role in liver disease progression.

Association Between PNPLA3 rs738409 C>G Variant and Liver-Related Outcomes in Patients With Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

Patients with nonalcoholic fatty liver disease (NAFLD) have an increased risk for liver-related complications, such as decompensation, hepatocellular carcinoma (HCC), and death; the severity of liver fibrosis and metabolic comorbidities are the main risk factors. A single nucleotide polymorphism in patatin-like phospholipase domain-containing-3 (PNPLA3) gene is associated with higher prevalence of liver damage and HCC, but there are no data from prospective studies of outcomes of patients with this polymorphism. We investigated whether the common rs738409 variant in PNPLA3 gene associates with the occurrence of liver-related events and death in a large cohort of patients with NAFLD.

METHODS

We followed 471 consecutive individuals at a hospital in Italy with a diagnosis of NAFLD based on histologic factors or a diagnosis of compensated NAFLD-related cirrhosis based on clinical factors for at least 6 months, from March 2004 through December 2018. We collected data on the occurrence of hepatic and extrahepatic outcomes, including decompensation and HCC, cardiovascular events and extrahepatic cancers, and overall and liver-related death. We detected the rs738409 G>C polymorphism in DNA from patient blood samples using the TaqMan assay.

RESULTS

During a median follow-up time of 64.6 months (range 6.1-175 months) 26 cases of decompensation, 13 HCCs, and 16 deaths (12 liver-related) were recorded. All liver-related events, including liver-related death, occurred in patients with F3 fibrosis or cirrhosis. The prevalence of PNPLA3 rs738409 GG, GT, and TT genotypes was 31.8%, 45.6%, and 22.6%, respectively. After adjusting for clinical, metabolic, and histologic risk factors, PNPLA3 C>G variant was associated with a higher risk of decompensation (hazard ratio [HR], 2.10; 95% CI, 1.03-4.29; P = .04), HCC (HR, 2.68; 95% CI, 1.01-7.26; P = .04), and liver-related death (HR, 3.64; 95% CI, 1.18-11.2; P = .02) by multivariate Cox regression analysis. In the subgroup of 162 patients with F3 fibrosis or cirrhosis, we confirmed the independent association between the PNPLA3 variant and decompensation (HR, 2.00; 95% CI, 1.01-3.97; P = .04), HCC (HR, 2.66; 95% CI, 1.02-7.13; P = .04), and liver-related death (HR, 3.64, 95% CI, 1.18-11.2; P = .02). We found no association between PNPLA3 genotype and cardiovascular events, extrahepatic cancers, or overall mortality.

CONCLUSIONS

Patients with NAFLD carrying PNPLA3 rs738409 G>C variant are at higher risk of liver-related events and death.

Aminopyrine breath test predicts liver-related events and death in HCV-related cirrhosis on SVR after DAA therapy

BACKGROUND & AIMS

In patients with hepatitis C virus (HCV)-related advanced cirrhosis, the effects of sustained virological response (SVR) by direct antiviral agents (DAAs) on decompensation and liver deaths are less clearcut, since up to 30% of patients do not improve, and no predictors of outcome have been identified. We used ¹³ C-aminopyrine breath test (ABT) to assess whether its changes can predict liver-related outcomes after DAA treatment in patients with HCV cirrhosis.

METHODS

Fifty consecutive patients with HCV cirrhosis were enrolled. Patients were included if they had Child A cirrhosis at risk for decompensation - defined as Child A6 (N = 22, 44%) or previous decompensation (N = 7, 14%) - or Child B cirrhosis (N = 21, 42%) eligible for DAA-based antiviral therapy. ABT was performed at baseline and 12 weeks after the end of antiviral therapy. Patients received sofosbuvir-based regimens.

RESULTS

Aminopyrine breath test was available for all 50 patients at baseline. The 120' cumulative dose was directly associated at regression analysis only with albumin levels (P = .001). ABT was available at follow-up week 12 for 41 patients (FUW12), all with SVR, and followed for a median of 25.2 months (range 12.2-32.1 months). Lower Ʌ ABT - defined as changes of 120' cumulative dose from FUW12 to baseline - (HR 0.97, 95% CI 0.94-0.99; P = .02) and FUW12 hepatic encephalopathy (HR 19.0, 95% CI 1.16-310.3; P = .03) were the only independent predictors of liver events/death at multivariate Cox regression analysis. The AUC of Ʌ ABT was good (0.87, 95% CI 0.75-0.97), with a delta ≥0% well discriminating patients at lower vs patients at higher risk of liver-related events/death (P < .001).

CONCLUSIONS

In patients with advanced HCV cirrhosis who achieve SVR with DAA, Ʌ ABT assists in assessing the residual likelihood of liver-related events and deaths after viral cure.