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Background / Aims: The association between NAFLD and psoriasis has never been explored in prospective epidemiological studies. The aim of this 2-phase study was to study the clinical features of NAFLD in patients with psoriasis. Methods: Phase 1: Investigation of prevalence and characteristics of NAFLD in an unselected cohort of 142 adult Italian outpatients with psoriasis vulgaris. Phase 2: Comparison of the psoriasis cohort subgroup with NAFLD and an age- and body mass index-matched retrospective cohort of 125 non-psoriasis patients with biopsy proven NAFLD. Results: Based on histories, laboratory tests, and ultrasound studies, 84 (59.2%) received clinical diagnosis of NAFLD; 30 had factors potentially associated with liver disease other than NAFLD (e.g., viral hepatitis, significant ethanol, methotrexate use); and 28 (19.7%) had normal livers. Comparison of the normal-liver and NAFLD subgroups revealed that NAFLD in psoriasis patients (Ps-NAFLD) was significantly correlated with metabolic syndrome (p <0.05); obesity (p =0.043); hypercholesterolemia (p =0.029); hypertriglyceridemia (p <0.001); AST/ALT ratio >1 (p =0.019), and psoriatic arthritis (PsA) (p =0.036). The association with PsA remained significant after logistic regression analysis (OR=3.94 [CI, 1.07–14.46]). Compared with the retrospective non-psoriatic NAFLD cohort (controls), Ps-NAFLD patients (cases) were likely to have severe NAFLD reflected by non-invasive NAFLD Fibrosis Scores and AST/ALT >1. Conclusions: NAFLD is highly prevalent among psoriasis patients, where it is closely associated with obesity (overall and abdominal), metabolic syndrome, and PsA, and more likely to cause severe liver fibrosis (compared with nonPs-NAFLD). Routine work-up for NAFLD may be warranted in patients with psoriasis, especially when potentially hepatotoxic drug therapy is being considered. [Copyright &y& Elsevier]

Background/Aims: The general public’s growing mistrust of the pharmaceutical industry and its perception of the lack of adverse effects of “natural” therapy have lead to the increasing use of “alternative drugs” for hypercholesterolemia. Methods: A sixty-three year old woman presented with severe hypertransaminasemia that had developed progressively over a few weeks. For six months she had been taking Equisterol®, an over-the-counter lipid-lowering product containing guggulsterol and red yeast rice extract. The product had been prescribed for hypercholesterolemia because the patient had developed hepatotoxicity while on lovastatin. Results: Liver biopsy revealed severe lobular necroinflammatory changes with an eosinophilic infiltrate. The episode was regarded as an adverse drug reaction after exclusion of other possible causes of acute liver disease and the prompt normalization of liver function tests after Equisterol® had been discontinued. Red yeast rice extract’s cholesterol-lowering properties are largely due to fungal metabolites known as monacolins, one of which – monacolin K – is identical to lovastatin. Conclusions: The choice of an alternative medicine approach in this case subjected the patient to “re-challenge” with the official medicine agent that had previously caused mild hepatotoxicity. Physicians should keep in mind that “alternative” medicine is not always the safest alternative and sometimes it is not even “alternative.” [Copyright &y& Elsevier]

Non-alcoholic fatty liver disease (NAFLD) is the leading cause of liver disorders and has a strong heritable component. The aim of this study was to identify new loci that contribute to severe NAFLD by examining rare variants. We performed whole-exome sequencing in individuals with NAFLD and advanced fibrosis or hepatocellular carcinoma (n = 301) and examined the enrichment of likely pathogenic rare variants vs. the general population. This was followed by validation at the gene level. In patients with severe NAFLD, we observed an enrichment of the p.P426L variant (rs143545741 C>T; odds ratio [OR] 5.26, 95% CI 2.1-12.6; p = 0.003) of autophagy-related 7 (ATG7) , which we characterized as a loss-of-function, vs. the general population, and an enrichment in rare variants affecting the catalytic domain (OR 13.9; 95% CI 1.9-612; p = 0.002). In the UK Biobank cohort, loss-of-function ATG7 variants increased the risk of cirrhosis and hepatocellular carcinoma (OR 3.30; 95% CI 1.1-7.5 and OR 12.30, 95% CI 2.6-36, respectively; p < 0.001 for both). The low-frequency loss-of-function p.V471A variant (rs36117895 T>C) was also associated with severe NAFLD in the clinical cohort (OR 1.7; 95% CI 1.2-2.5; p = 0.003), predisposed to hepatocellular ballooning (p = 0.007) evolving to fibrosis in the Liver biopsy cohort (n = 2,268), and was associated with liver injury in the UK Biobank (aspartate aminotransferase levels, p < 0.001), with a larger effect in severely obese individuals in whom it was linked to hepatocellular carcinoma (p = 0.009). ATG7 protein localized to periportal hepatocytes, particularly in the presence of ballooning. In the Liver Transcriptomic cohort (n = 125), ATG7 expression correlated with suppression of the TNFα pathway, which was conversely upregulated in p.V471A carriers. We identified rare and low-frequency ATG7 loss-of-function variants that promote NAFLD progression by impairing autophagy and facilitating ballooning and inflammation. We found that rare mutations in a gene called autophagy-related 7 (ATG7) increase the risk of developing severe liver disease in individuals with dysmetabolism. These mutations cause an alteration in protein function and impairment of self-renewal of cellular content, leading to liver damage and inflammation. [Display omitted] • NAFLD is the leading cause of liver disorders and has a strong heritable component. • Rare loss-of-function ATG7 gene mutations increase the risk of severe liver disease in patients with NAFLD. • ATG7 mutations cause altered protein function and impairment of autophagy, leading to hepatocellular ballooning and inflammation. • The most frequent variant is responsible for a meaningful fraction of predisposition to ballooning and hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) risk stratification in individuals with dysmetabolism is a major unmet need. Genetic predisposition contributes to non-alcoholic fatty liver disease (NAFLD). We aimed to exploit robust polygenic risk scores (PRS) that can be evaluated in the clinic to gain insight into the causal relationship between NAFLD and HCC, and to improve HCC risk stratification. We examined at-risk individuals (NAFLD cohort, n = 2,566; 226 with HCC; and a replication cohort of 427 German patients with NAFLD) and the general population (UK Biobank [UKBB] cohort, n = 364,048; 202 with HCC). Variants in PNPLA3-TM6SF2-GCKR-MBOAT7 were combined in a hepatic fat PRS (PRS-HFC), and then adjusted for HSD17B13 (PRS-5). In the NAFLD cohort, the adjusted impact of genetic risk variants on HCC was proportional to the predisposition to fatty liver (p = 0.002) with some heterogeneity in the effect. PRS predicted HCC more robustly than single variants (p < 10-13). The association between PRS and HCC was mainly mediated through severe fibrosis, but was independent of fibrosis in clinically relevant subgroups, and was also observed in those without severe fibrosis (p < 0.05). In the UKBB cohort, PRS predicted HCC independently of classical risk factors and cirrhosis (p < 10-7). In the NAFLD cohort, we identified high PRS cut-offs (≥0.532/0.495 for PRS-HFC/PRS-5) that in the UKBB cohort detected HCC with ~90% specificity but limited sensitivity; PRS predicted HCC both in individuals with (p < 10-5) and without cirrhosis (p < 0.05). Our results are consistent with a causal relationship between hepatic fat and HCC. PRS improved the accuracy of HCC detection and may help stratify HCC risk in individuals with dysmetabolism, including those without severe liver fibrosis. Further studies are needed to validate our findings. By analyzing variations in genes that contribute to fatty liver disease, we developed two risk scores to help predict liver cancer in individuals with obesity-related metabolic complications. These risk scores can be easily tested in the clinic. We showed that the risk scores helped to identify the risk of liver cancer both in high-risk individuals and in the general population. [Display omitted] • Genetic predisposition to liver fat accumulation predisposes to cirrhosis and HCC. • Hepatic fat promotes carcinogenesis, partly via fibrosis. • Polygenic risk scores may improve HCC risk stratification during dysmetabolism. [ABSTRACT FROM AUTHOR]

• The KLB rs17618244 variant increases the risk of ballooning and lobular inflammation in children with NAFLD. • KLB plasma levels are lower in carriers of the rs17618244 minor A allele. • KLB plasma levels are associated with lobular inflammation, ballooning and fibrosis. • KLB mutant induces intracellular lipid accumulation in HepG2 and Huh7. • KLB mutant causes upregulation of lipotoxic and proinflammatory genes. Non-alcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease in adults and children. Along with obesity, diabetes and insulin resistance, genetic factors strongly impact on NAFLD development and progression. Dysregulated bile acid metabolism and the fibroblast growth factor 19 (FGF19) pathway play a pivotal role in NAFLD pathogenesis. However, the mechanism through which the FGF19 receptor system is associated with liver damage in NAFLD remains to be defined. We evaluated the impact of the rs17618244 G>A β-Klotho (KLB) variant on liver damage in 249 pediatric patients with biopsy-proven NAFLD and the association of this variant with the expression of hepatic and soluble KLB. In vitro models were established to investigate the role of the KLB mutant. The KLB rs17618244 variant was associated with an increased risk of ballooning and lobular inflammation. KLB plasma levels were lower in carriers of the rs17618244 minor A allele and were associated with lobular inflammation, ballooning and fibrosis. In HepG2 and Huh7 hepatoma cell lines, exposure to free fatty acids caused a severe reduction of intracellular and secreted KLB. Finally, KLB downregulation obtained by the expression of a KLB mutant in HepG2 and Huh7 cells induced intracellular lipid accumulation and upregulation of p62, ACOX1, ACSL1, IL-1β and TNF-α gene expression. In conclusion, we showed an association between the rs17618244 KLB variant, which leads to reduced KLB expression, and the severity of NAFLD in pediatric patients. We can speculate that the KLB protein may exert a protective role against lipotoxicity and inflammation in hepatocytes. Genetic and environmental factors strongly impact on the pathogenesis and progression of non-alcoholic fatty liver disease (NAFLD). The FGF19/FGFR4/KLB pathway plays a pivotal role in the pathogenesis of NAFLD. The aim of the study was to investigate the impact of a genetic variant in the KLB gene on the severity of liver disease. Our data suggest that the KLB protein plays a protective role against lipotoxicity and inflammation in hepatocytes. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Irisin, the cleaved extra-cellular fragment of FNDC5 is a myokine thought to have favorable metabolic activity. • The role of variants in the FNDC5 gene in NAFLD is not defined. • Genetic variants in FNDC5 confer risk of human severe hepatic steatosis. • Functional studies reveal that this variant mediates this effect via a miRNA-mediated control of FNDC5 mRNA stability. • Irisin is likely to have a favourable metabolic impact on NAFLD. Background & Aims Irisin, the cleaved extra-cellular fragment of the Fibronectin type III domain-containing protein 5 (FNDC5) is a myokine that is proposed to have favorable metabolic activity. We aimed to elucidate the currently undefined role of variants in the FNDC5 gene in non-alcoholic fatty liver disease (NAFLD). Methods We prioritized single nucleotide polymorphisms in FNDC5 on the basis of their putative biological function and identified rs3480 in the 3′ untranslated region (3′UTR). We studied the association of rs3480 with liver disease severity and the metabolic profile of 987 Caucasian patients with NAFLD. Functional investigations were undertaken using luciferase reporter assays of the 3′UTR of human FNDC5, pyrosequencing for allele-specific expression of FNDC5 in liver, measurement of serum irisin, and bioinformatics analysis. Results The rs3480 (G) allele was associated with advanced steatosis (OR 1.29; 95% CI 1.08–1.55; p = 0.004), but not with other histological features. This effect was independent but additive to PNPLA3 and TM6SF2. The rs3480 polymorphism influenced FNDC5 mRNA stability and the binding of miR-135a-5P. Compared with controls, hepatic expression of this microRNA was upregulated while FNDC5 expression was downregulated. Elevated serum irisin was associated with reduced steatosis, and an improved metabolic profile. Conclusions Carriage of the FNDC5 rs3480 minor (G) allele is associated with more severe steatosis in NAFLD through a microRNA-mediated mechanism controlling FNDC5 mRNA stability. Irisin is likely to have a favorable metabolic impact on NAFLD. Lay summary Irisin is a novel protein produced mainly by muscle, which is known to be released into the circulation, with an unclear role in liver fat deposition. This study demonstrates that genetic variants in the gene encoding the irisin protein modulate the risk of liver fat in patients with fatty liver disease. Interestingly, these effects are independent of, but additive to those of other recently described genetic variants that contribute to liver fat. In functional studies, we have deciphered the detailed molecular mechanisms by which this genetic variant mediates its effects. [ABSTRACT FROM AUTHOR]

Summary: Non-alcoholic fatty liver disease (NAFLD) is a multi-faceted disorder, which ranges from simple steatosis to non-alcoholic steatohepatitis (NASH) with/without fibrosis. The effects of specific risk factors, such as obesity and sedentary lifestyle, on predisposing genetic settings eventually lead to the development of NAFLD in children. The complex interplay between genes and environment in NAFLD pathogenesis is sustained by multiple mechanisms that involve liver crosstalk with other organs and tissues, especially gut and adipose tissue. Unfortunately, natural history of paediatric NAFLD is lacking, and the etiopathogenesis is still in the process of being defined. Potential early predictors and suitable non-invasive diagnostic tools can be discovered based on the pathogenetic mechanisms and histological patterns. This will also help design novel treatments and a comprehensive and successful management strategy for patients. In this review, we discuss the recent advances made in genetics, etiopathogenesis, diagnosis, and therapeutic management of NAFLD, focusing especially on the obesity-related steatotic liver condition. [ABSTRACT FROM AUTHOR]

Background & Aims: Increased visceral adiposity is considered the hallmark of the metabolic syndrome, whose hepatic manifestation is nonalcoholic fatty liver disease (NAFLD), although a subset of patients does not have visceral obesity. Our study aimed to compare metabolic alterations and liver damage in patients with NAFLD with and without visceral obesity. Methods: Four hundred and thirty one consecutive patients with liver biopsy-confirmed NAFLD were divided in three groups according to waist circumference, the simplest surrogate marker of visceral obesity. One hundred and thirty three patients (31%) had a waist circumference⩽94 (males) and⩽80cm (females) (group A), 157 (36%) between 94 and 102, and 80 and 88 (B), and the remaining 141 (33%) had values higher than 102 and 88cm (C). Results: Significant trends for older age, higher prevalence of female gender, lower HDL, higher triglycerides, altered glucose metabolism, hypertension, and metabolic syndrome were observed with increasing visceral adiposity. In contrast, non-alcoholic steatohepatitis (NASH) detected in 55% and 72% of patients with normal and increased waist circumference, respectively, and the presence of fibrosis⩾2 were not associated with visceral adiposity. Alanine aminotransferase (ALT), ferritin, HOMA-IR>4, and severe steatosis were independently associated with NASH, whereas ferritin and impaired glucose tolerance were associated with fibrosis⩾2. Conclusions: Patients with normal waist circumference, despite milder metabolic alterations, may have NASH and are at risk of developing fibrosis, suggesting that once NAFLD is present, visceral obesity is not a major determinant of liver damage severity. [ABSTRACT FROM AUTHOR]