0000000000217653
AUTHOR
Sara Badiali
Protein phosphatase 1 regulatory subunit 3B gene variation protects against hepatic fat accumulation and fibrosis in individuals at high risk of nonalcoholic fatty liver disease
Nonalcoholic fatty liver disease (NAFLD) is a major cause of liver damage and has a strong genetic component. The rs4841132 G>A variant, modulating the expression of protein phosphatase 1 regulatory subunit 3B (PPP1R3B), which is involved in glycogen synthesis, has been reported to reduce the risk of NAFLD but at the same time may favor liver disease by facilitating glycogen accumulation. The aim of this study was to assess the impact of rs4841132 on development of histologic steatosis and fibrosis in 1,388 European individuals in a liver biopsy cohort, on NAFLD hepatocellular carcinoma in a cross-sectional Italian cohort (n = 132 cases), and on liver disease at the population level in the …
Mboat7 down-regulation by hyper-insulinemia induces fat accumulation in hepatocytes.
Background: Naturally occurring variation in Membrane-bound O-acyltransferase domain-containing 7 (MBOAT7), encoding for an enzyme involved in phosphatidylinositol acyl-chain remodelling, has been associated with fatty liver and hepatic disorders. Here, we examined the relationship between hepatic Mboat7 down-regulation and fat accumulation. Methods: Hepatic MBOAT7 expression was surveyed in 119 obese individuals and in experimental models. MBOAT7 was acutely silenced by antisense oligonucleotides in C57Bl/6 mice, and by CRISPR/Cas9 in HepG2 hepatocytes. Findings: In obese individuals, hepatic MBOAT7 mRNA decreased from normal liver to steatohepatitis, independently of diabetes, inflammatio…
Prevalence and Risk Factors of Significant Fibrosis in Patients With Nonalcoholic Fatty Liver Without Steatohepatitis
In patients with nonalcoholic fatty liver disease (NAFLD), nonalcoholic steatohepatitis (NASH) is a risk factor for the development of fibrosis. However, fibrosis has been observed in livers of patients without NASH. We aimed to estimate the prevalence of fibrosis in patients without NASH and risk factors for fibrosis.We analyzed data from 1738 subjects (44.9% with severe obesity) in a cross-sectional liver biopsy cohort enrolled at referral centers in Italy and Finland. Biopsy specimens were analyzed histologically by a blinded pathologist at each center, and a diagnosis of NASH was made based on steatosis (≥5% of hepatocytes), hepatocellular ballooning, and lobular inflammation. We also c…
The rs2294918 E434K variant modulates patatin-like phospholipase domain-containing 3 expression and liver damage
The patatin-like phosholipase domain-containing 3 (PNPLA3) rs738409 polymorphism (I148M) is a major determinant of hepatic fat and predisposes to the full spectrum of liver damage in nonalcoholic fatty liver disease (NAFLD). The aim of this study was to evaluate whether additional PNPLA3 coding variants contribute to NAFLD susceptibility, first in individuals with contrasting phenotypes (with early-onset NAFLD vs. very low aminotransferases) and then in a large validation cohort. Rare PNPLA3 variants were not detected by sequencing coding regions and intron-exon boundaries either in 142 patients with early-onset NAFLD nor in 100 healthy individuals with alanine aminotransferase22/20 IU/mL. …
Interferon lambda 4 rs368234815 TT>δG variant is associated with liver damage in patients with nonalcoholic fatty liver disease
Background and Aims: The IFNL3/4 locus influencing innate immunity regulation has been associated with the severity of hepatitis and fibrosis progression during chronic hepatitis C infection, while contrasting results were reported in NAFLD. In this study, we examined whether rs12979860 and the linked causal rs368234815 variant encoding for the alternative IFNL4 protein variant are associated with liver fibrosis and damage in a large multicenter cohort of patients at risk of NASH. To clarify the mechanism, we also evaluated the impact on interferon-stimulated gene (ISG) hepatic expression in a subset of patients. Methods: We considered 946 consecutive Italian individuals at risk of NASH wit…
PCSK7 gene variation bridges atherogenic dyslipidemia with hepatic inflammation in NAFLD patients
Dyslipidemia and altered iron metabolism are typical features of nonalcoholic fatty liver disease (NAFLD). Proprotein convertase subtilisin/kexin type 7 (PCSK7) gene variation has been associated with circulating lipids and liver damage during iron overload. The aim of this study was to examine the impact of the PCSK7 rs236918 variant on NAFLDrelated traits in 1,801 individuals from the Liver Biopsy Cohort (LBC), 500,000 from the UK Biobank Cohort (UKBBC), and 4,580 from the Dallas Heart Study (DHS). The minor PCSK7 rs236918 C allele was associated with higher triglycerides, aminotransferases, and hepatic inflammation in the LBC (P < 0.05) and with hypercholesterolemia and liver disease …