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1.
Environ Health Perspect ; 130(4): 46001, 2022 04.
Article in English | MEDLINE | ID: mdl-35475652

ABSTRACT

BACKGROUND: Experimental evidence indicates that exposure to certain pollutants is associated with liver damage. Per- and polyfluoroalkyl substances (PFAS) are persistent synthetic chemicals widely used in industry and consumer products and bioaccumulate in food webs and human tissues, such as the liver. OBJECTIVE: The objective of this study was to conduct a systematic review of the literature and meta-analysis evaluating PFAS exposure and evidence of liver injury from rodent and epidemiological studies. METHODS: PubMed and Embase were searched for all studies from earliest available indexing year through 1 December 2021 using keywords corresponding to PFAS exposure and liver injury. For data synthesis, results were limited to studies in humans and rodents assessing the following indicators of liver injury: serum alanine aminotransferase (ALT), nonalcoholic fatty liver disease, nonalcoholic steatohepatitis, or steatosis. For human studies, at least three observational studies per PFAS were used to conduct a weighted z-score meta-analysis to determine the direction and significance of associations. For rodent studies, data were synthesized to qualitatively summarize the direction and significance of effect. RESULTS: Our search yielded 85 rodent studies and 24 epidemiological studies, primarily of people from the United States. Studies focused primarily on legacy PFAS: perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorononanoic acid (PFNA), and perfluorohexanesulfonic acid. Meta-analyses of human studies revealed that higher ALT levels were associated with exposure to PFOA (z-score= 6.20, p<0.001), PFOS (z-score= 3.55, p<0.001), and PFNA (z-score= 2.27, p=0.023). PFOA exposure was also associated with higher aspartate aminotransferase and gamma-glutamyl transferase levels in humans. In rodents, PFAS exposures consistently resulted in higher ALT levels and steatosis. CONCLUSION: There is consistent evidence for PFAS hepatotoxicity from rodent studies, supported by associations of PFAS and markers of liver function in observational human studies. This review identifies a need for additional research evaluating next-generation PFAS, mixtures, and early life exposures. https://doi.org/10.1289/EHP10092.


Subject(s)
Environmental Pollutants , Fluorocarbons , Non-alcoholic Fatty Liver Disease , Biomarkers , Humans , United States
2.
Nat Commun ; 13(1): 1440, 2022 03 17.
Article in English | MEDLINE | ID: mdl-35301333

ABSTRACT

There has been a global increase in rates of obesity with a parallel epidemic of non-alcoholic fatty liver disease (NAFLD). Autophagy is an essential mechanism involved in the degradation of cellular material and has an important function in the maintenance of liver homeostasis. Here, we explore the effect of Autophagy-related 5 (Atg5) deficiency in liver CD11c+ cells in mice fed HFD. When compared to control mice, Atg5-deficient CD11c+ mice exhibit increased glucose intolerance and decreased insulin sensitivity when fed HFD. This phenotype is associated with the development of NAFLD. We observe that IL-23 secretion is induced in hepatic CD11c+ myeloid cells following HFD feeding. We demonstrate that both therapeutic and preventative IL-23 blockade alleviates glucose intolerance, insulin resistance and protects against NAFLD development. This study provides insights into the function of autophagy and IL-23 production by hepatic CD11c+ cells in NAFLD pathogenesis and suggests potential therapeutic targets.


Subject(s)
Insulin Resistance , Non-alcoholic Fatty Liver Disease , Animals , Autophagy , Diet, High-Fat/adverse effects , Insulin Resistance/genetics , Interleukin-23/metabolism , Liver/metabolism , Mice , Mice, Inbred C57BL , Non-alcoholic Fatty Liver Disease/metabolism
3.
Am J Hum Genet ; 109(2): 299-310, 2022 02 03.
Article in English | MEDLINE | ID: mdl-35090584

ABSTRACT

Spontaneous clearance of acute hepatitis C virus (HCV) infection is associated with single nucleotide polymorphisms (SNPs) on the MHC class II. We fine-mapped the MHC region in European (n = 1,600; 594 HCV clearance/1,006 HCV persistence) and African (n = 1,869; 340 HCV clearance/1,529 HCV persistence) ancestry individuals and evaluated HCV peptide binding affinity of classical alleles. In both populations, HLA-DQß1Leu26 (p valueMeta = 1.24 × 10-14) located in pocket 4 was negatively associated with HCV spontaneous clearance and HLA-DQß1Pro55 (p valueMeta = 8.23 × 10-11) located in the peptide binding region was positively associated, independently of HLA-DQß1Leu26. These two amino acids are not in linkage disequilibrium (r2 < 0.1) and explain the SNPs and classical allele associations represented by rs2647011, rs9274711, HLA-DQB1∗03:01, and HLA-DRB1∗01:01. Additionally, HCV persistence classical alleles tagged by HLA-DQß1Leu26 had fewer HCV binding epitopes and lower predicted binding affinities compared to clearance alleles (geometric mean of combined IC50 nM of persistence versus clearance; 2,321 nM versus 761.7 nM, p value = 1.35 × 10-38). In summary, MHC class II fine-mapping revealed key amino acids in HLA-DQß1 explaining allelic and SNP associations with HCV outcomes. This mechanistic advance in understanding of natural recovery and immunogenetics of HCV might set the stage for much needed enhancement and design of vaccine to promote spontaneous clearance of HCV infection.


Subject(s)
HLA-DQ beta-Chains/genetics , Hepacivirus/pathogenicity , Hepatitis C/genetics , Host-Pathogen Interactions/genetics , Polymorphism, Single Nucleotide , Acute Disease , Alleles , Amino Acid Substitution , Black People , Female , Gene Expression , Genome-Wide Association Study , Genotype , HLA-DQ beta-Chains/immunology , Hepacivirus/growth & development , Hepacivirus/immunology , Hepatitis C/ethnology , Hepatitis C/immunology , Hepatitis C/virology , Host-Pathogen Interactions/immunology , Humans , Leucine/immunology , Leucine/metabolism , Male , Proline/immunology , Proline/metabolism , Protein Isoforms/genetics , Protein Isoforms/immunology , Remission, Spontaneous , White People
4.
Hepatol Commun ; 5(10): 1689-1703, 2021 10.
Article in English | MEDLINE | ID: mdl-34558842

ABSTRACT

Most genetic studies of nonalcoholic fatty liver disease (NAFLD) have been conducted in Whites. In this large and ethnically diverse cohort, we assessed the transportability of previously identified genetic variants for NAFLD, built a genetic risk score (GRS), and examined its association with NAFLD risk in multiple ethnic groups. Thirty previously identified genome-wide association studies (GWAS) variants (P < 5 × 10-8 ) and 17 other variants associated with NAFLD were examined in a nested case-control study of NAFLD (1,448 cases/8,444 controls) in this multi-ethnic cohort study. We then built a GRS using 11 independent single-nucleotide polymorphisms from these prior studies and examined its association with NAFLD by cirrhosis status across multiple ethnic groups. Of the 30 GWAS SNPs, 20 (67%) were replicated (P < 0.05) in the pooled multi-ethnic population. The highest percentage of replication was seen in Latinos (43%), followed by Japanese Americans (37%), Whites (17%), and Native Hawaiians and African Americans (≤10%). Several genetic variants, including those in PNPLA3 (patatin-like phospholipase domain containing 3), HSD17B13 (hydroxysteroid 17-beta dehydrogenase 13), TM6SF2 (transmembrane 6 superfamily member 2), GATAD2A (GATA zinc finger domain containing 2A), GCKR (glucokinase regulator), SUGP1 (SURP and G-patch domain containing 1), MBOAT7 (membrane bound O-acyltransferase domain containing 7), TRIB1 (tribbles pseudokinase 1), SAMM50 (sorting and assembly machinery component), and ERLIN1 (ER lipid raft associated 1)-CHUK (component of inhibitor of nuclear factor kappa B kinase complex)-CWF19L1 (CWF19 like cell cycle control factor 1) gene cluster, were replicated in at least two ethnic groups. An 11-SNP weighted GRS was associated with NAFLD risk in the multi-ethnic population (odds ratio [OR] per SD increase = 1.41; 95% confidence interval [CI] = 1.32-1.50), as well as in each ethnic group (OR ranged from 1.30 in African Americans to 1.52 in Latinos). The GRS-NAFLD association was stronger for NAFLD with cirrhosis (OR = 1.67; 95% CI = 1.46-1.92) compared to NAFLD without cirrhosis (OR = 1.37; 95% CI = 1.28-1.46) (P heterogeneity = 0.003). Conclusion: In this ethnically diverse cohort, we replicated several key genetic variants for NAFLD and showed the utility of GRS based on the risk alleles for NAFLD risk stratification in multiple ethnic groups.


Subject(s)
Ethnicity/genetics , Genetic Predisposition to Disease/ethnology , Non-alcoholic Fatty Liver Disease/ethnology , Non-alcoholic Fatty Liver Disease/genetics , Aged , California/epidemiology , Case-Control Studies , Female , Genetic Predisposition to Disease/epidemiology , Genome-Wide Association Study , Hawaii/epidemiology , Humans , Male , Middle Aged , Non-alcoholic Fatty Liver Disease/epidemiology , Polymorphism, Single Nucleotide , Risk Factors
5.
PLoS Pathog ; 17(8): e1009799, 2021 08.
Article in English | MEDLINE | ID: mdl-34370798

ABSTRACT

Chronic infection with HCV is manifested by dysregulation of innate immune responses and impaired T cell function at multiple levels. These changes may impact susceptibility to other infections, responsiveness to antiviral therapies, vaccine responsiveness, and development of complications such as hepatocellular carcinoma. Highly effective direct-acting antiviral (DAA) therapy has revolutionized the management of chronic HCV, with expected cure rates exceeding 95%. DAA treatment represents a unique opportunity to investigate to what extent elimination of viral replication and chronic antigen stimulation can restore immunologic phenotype. In this study we interrogated the global transcriptional profile of isolated peripheral blood T cells before, during and after IFN-free DAA therapy using single-cell mRNA sequencing. Our results demonstrate that T cells mapped at single-cell resolution have dramatic transcriptomic changes early after initiation of DAA and many of these changes are sustained after completion of DAA therapy. Specifically, we see a significant reduction in transcripts associated with innate immune activation and interferon signaling such as ISG15, ISG20, IFIT3, OAS and MX1 in many different T cell subsets. Furthermore, we find an early upregulation of a gene involved in suppression of immune activation, DUSP1, in circulating T cells. Conclusion: This study provides the first in-depth transcriptomic analysis at the single-cell level of patients undergoing DAA therapy, demonstrating that IFN-free antiviral therapy in chronic HCV infection induces hitherto unrecognized shifts in innate immune and interferon signaling within T cell populations early, during, and long-term after treatment. The present study provides a rich data source to explore the effects of DAA treatment on bulk T cells.


Subject(s)
Antiviral Agents/therapeutic use , Gene Expression Regulation/drug effects , Hepatitis C, Chronic/genetics , Interferons/genetics , Single-Cell Analysis/methods , T-Lymphocyte Subsets/metabolism , Transcriptome/drug effects , Biomarkers/blood , Hepacivirus/drug effects , Hepacivirus/physiology , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/virology , Humans , Interferons/metabolism , Male , Prospective Studies , T-Lymphocyte Subsets/drug effects
6.
Front Immunol ; 12: 671073, 2021.
Article in English | MEDLINE | ID: mdl-34012454

ABSTRACT

The liver is the central organ for cholesterol synthesis and homeostasis. The effects of dietary cholesterol on hepatic injury, mainly of oxidized low-density lipoproteins (OxLDL), are not fully understood. Here, we show that the degree of cholesterol oxidation had different impacts on the global gene expression of human M2-like macrophages, with highly oxidized LDL causing the most dramatic changes. M2-like macrophages and Kupffer cells undergo M4-like polarization, decreasing the expression of important markers, such as IL10, MRC1, and CD163. These cells also displayed functional changes, with reduced phagocytic capacity, increased neutrophil recruitment, and more effective neutrophil extracellular traps (NETs) induction. Our findings provide a link between LDL oxidation and modification of peripheral and liver macrophage function.


Subject(s)
Cholesterol/metabolism , Extracellular Traps/metabolism , Kupffer Cells/immunology , Macrophages/immunology , Neutrophils/physiology , Antigens, CD/metabolism , Antigens, Differentiation, Myelomonocytic/metabolism , Cell Differentiation , Cells, Cultured , Gene Expression Regulation , Humans , Interleukin-10/metabolism , Membrane Glycoproteins , Phagocytosis , Receptors, Cell Surface/metabolism , Receptors, Immunologic
7.
iScience ; 24(5): 102457, 2021 May 21.
Article in English | MEDLINE | ID: mdl-34013171

ABSTRACT

Translocator protein (TSPO, 18 kDa) levels increase in parallel with the evolution of simple steatosis (SS) to nonalcoholic steatohepatitis (NASH) in nonalcoholic fatty liver disease (NAFLD). However, TSPO function in SS and NASH is unknown. Loss of TSPO in hepatocytes in vitro downregulated acetyl-CoA acetyltransferase 2 and increased free cholesterol (FC). FC accumulation induced endoplasmic reticulum stress via IRE1A and protein kinase RNA-like ER kinase/ATF4/CCAAT-enhancer-binding protein homologous protein pathways and autophagy. TSPO deficiency activated cellular adaptive antioxidant protection; this adaptation was lost upon excessive FC accumulation. A TSPO ligand 19-Atriol blocked cholesterol binding and recapitulated many of the alterations seen in TSPO-deficient cells. These data suggest that TSPO deficiency accelerated the progression of SS. In NASH, however, loss of TSPO ameliorated liver fibrosis through downregulation of bile acid synthesis by reducing CYP7A1 and CYP27A1 levels and increasing farnesoid X receptor expression. These studies indicate a dynamic and complex role for TSPO in the evolution of NAFLD.

8.
Hepatology ; 74(3): 1546-1559, 2021 09.
Article in English | MEDLINE | ID: mdl-33730435

ABSTRACT

BACKGROUND AND AIMS: Nonalcoholic fatty liver disease (NAFLD) is the most prevalent cause of liver disease in children. Mercury (Hg), a ubiquitous toxic metal, has been proposed as an environmental factor contributing to toxicant-associated fatty liver disease. APPROACH AND RESULTS: We investigated the effect of prenatal exposure to Hg on childhood liver injury by combining epidemiological results from a multicenter mother-child cohort with complementary in vitro experiments on monocyte cells that are known to play a key role in liver immune homeostasis and NAFLD. We used data from 872 mothers and their children (median age, 8.1 years; interquartile range [IQR], 6.5-8.7) from the European Human Early-Life Exposome cohort. We measured Hg concentration in maternal blood during pregnancy (median, 2.0 µg/L; IQR, 1.1-3.6). We also assessed serum levels of alanine aminotransferase (ALT), a common screening tool for pediatric NAFLD, and plasma concentrations of inflammation-related cytokines in children. We found that prenatal Hg exposure was associated with a phenotype in children that was characterized by elevated ALT (≥22.1 U/L for females and ≥25.8 U/L for males) and increased concentrations of circulating IL-1ß, IL-6, IL-8, and TNF-α. Consistently, inflammatory monocytes exposed in vitro to a physiologically relevant dose of Hg demonstrated significant up-regulation of genes encoding these four cytokines and increased concentrations of IL-8 and TNF-α in the supernatants. CONCLUSIONS: These findings suggest that developmental exposure to Hg can contribute to inflammation and increased NAFLD risk in early life.


Subject(s)
Mercury/blood , Non-alcoholic Fatty Liver Disease/epidemiology , Prenatal Exposure Delayed Effects/epidemiology , Adult , Alanine Transaminase , Child , Cohort Studies , Cytokines , Disease Susceptibility , Exposome , Female , Humans , Inflammation , Interleukin-1beta/genetics , Interleukin-1beta/metabolism , Interleukin-6/genetics , Interleukin-6/metabolism , Interleukin-8/genetics , Interleukin-8/metabolism , Male , Maternal Exposure , Non-alcoholic Fatty Liver Disease/genetics , Non-alcoholic Fatty Liver Disease/metabolism , Pregnancy , Prenatal Exposure Delayed Effects/genetics , Prenatal Exposure Delayed Effects/metabolism , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism
9.
Hepatology ; 74(2): 1049-1064, 2021 08.
Article in English | MEDLINE | ID: mdl-33577086

ABSTRACT

The aim of this document is to provide a concise scientific review of the currently available COVID-19 vaccines and those in development, including mRNA, adenoviral vectors, and recombinant protein approaches. The anticipated use of COVID-19 vaccines in patients with chronic liver disease (CLD) and liver transplant (LT) recipients is reviewed and practical guidance is provided for health care providers involved in the care of patients with liver disease and LT about vaccine prioritization and administration. The Pfizer and Moderna mRNA COVID-19 vaccines are associated with a 94%-95% vaccine efficacy compared to placebo against COVID-19. Local site reactions of pain and tenderness were reported in 70%-90% of clinical trial participants, and systemic reactions of fever and fatigue were reported in 40%-70% of participants, but these reactions were generally mild and self-limited and occurred more frequently in younger persons. Severe hypersensitivity reactions related to the mRNA COVID-19 vaccines are rare and more commonly observed in women and persons with a history of previous drug reactions for unclear reasons. Because patients with advanced liver disease and immunosuppressed patients were excluded from the vaccine licensing trials, additional data regarding the safety and efficacy of COVID-19 vaccines are eagerly awaited in these and other subgroups. Remarkably safe and highly effective mRNA COVID-19 vaccines are now available for widespread use and should be given to all adult patients with CLD and LT recipients. The online companion document located at https://www.aasld.org/about-aasld/covid-19-resources will be updated as additional data become available regarding the safety and efficacy of other COVID-19 vaccines in development.


Subject(s)
COVID-19 Vaccines/standards , COVID-19/prevention & control , Liver Diseases , Liver Transplantation , Adult , COVID-19 Vaccines/administration & dosage , Consensus , Humans , Practice Guidelines as Topic , SARS-CoV-2/immunology , United States
10.
J Med Virol ; 93(5): 2645-2653, 2021 05.
Article in English | MEDLINE | ID: mdl-33090515

ABSTRACT

Coronavirus disease 2019, the infectious disease caused by severe acute respiratory syndrome coronavirus-2, has resulted in a global pandemic with unprecedented health, societal, and economic impact. The disease often manifests with flu-like symptoms and is dominated by pulmonary complications, but widely diverse clinical manifestations involving multiple organ systems can result. We posit that viral tropism and the aberrant host immune response mediate the protean findings and severity in this disease. In general, extrapulmonary manifestations are a harbinger of or contemporaneously associate with disease progression, but in the case of some extrapulmonary findings (gastrointestinal and dermatologic), may track with milder disease. The precise underlying pathophysiological mechanisms remain incompletely elucidated, and additional immune phenotyping studies are warranted to reveal early correlates of disease outcomes and novel therapeutic targets.


Subject(s)
COVID-19/immunology , Immunity, Innate , Immunity , SARS-CoV-2/immunology , COVID-19/pathology , COVID-19/physiopathology , Coinfection/complications , Humans , Pandemics , Viral Tropism
11.
J Infect Dis ; 223(12): 2090-2098, 2021 06 15.
Article in English | MEDLINE | ID: mdl-33119750

ABSTRACT

BACKGROUND: Spontaneous clearance of acute hepatitis C virus (HCV) infection is more common in women than in men, independent of known risk factors. METHODS: To identify sex-specific genetic loci, we studied 4423 HCV-infected individuals (2903 male, 1520 female) of European, African, and Hispanic ancestry. We performed autosomal, and X chromosome sex-stratified and combined association analyses in each ancestry group. RESULTS: A male-specific region near the adenosine diphosphate-ribosylation factor-like 5B (ARL5B) gene was identified. Individuals with the C allele of rs76398191 were about 30% more likely to have chronic HCV infection than individuals with the T allele (OR, 0.69; P = 1.98 × 10-07), and this was not seen in females. The ARL5B gene encodes an interferon-stimulated gene that inhibits immune response to double-stranded RNA viruses. We also identified suggestive associations near septin 6 and ribosomal protein L39 genes on the X chromosome. In box sexes, allele G of rs12852885 was associated with a 40% increase in HCV clearance compared with the A allele (OR, 1.4; P = 2.46 × 10-06). Septin 6 facilitates HCV replication via interaction with the HCV NS5b protein, and ribosomal protein L39 acts as an HCV core interactor. CONCLUSIONS: These novel gene associations support differential mechanisms of HCV clearance between the sexes and provide biological targets for treatment or vaccine development.


Subject(s)
Hepatitis C , Sex Factors , Female , Genome-Wide Association Study , Hepacivirus/genetics , Hepatitis C/genetics , Humans , Male , Polymorphism, Single Nucleotide , Ribosomal Proteins/genetics , Septins/genetics , Viral Load
12.
Cell Mol Gastroenterol Hepatol ; 11(2): 573-595, 2021.
Article in English | MEDLINE | ID: mdl-32961356

ABSTRACT

BACKGROUND AND AIMS: As the incidence of nonalcoholic steatohepatitis (NASH) continues to rise, understanding how normal liver functions are affected during disease is required before developing novel therapeutics which could reduce morbidity and mortality. However, very little is understood about how the transport of proteins and cells from the liver by the lymphatic vasculature is affected by inflammatory mediators or during disease. METHODS: To answer these questions, we utilized a well-validated mouse model of NASH and exposure to highly oxidized low density lipoprotein (oxLDL). In addition to single cell sequencing, multiplexed immunofluorescence and metabolomic analysis of liver lymphatic endothelial cells (LEC)s we evaluated lymphatic permeability and transport both in vitro and in vivo. RESULTS: Confirming similarities between human and mouse liver lymphatic vasculature in NASH, we found that the lymphatic vasculature expands as disease progresses and results in the downregulation of genes important to lymphatic identity and function. We also demonstrate, in mice with NASH, that fluorescein isothiocyanate (FITC) dextran does not accumulate in the liver draining lymph node upon intrahepatic injection, a defect that was rescued with therapeutic administration of the lymphatic growth factor, recombinant vascular endothelial growth factor C (rVEGFC). Similarly, exposure to oxLDL reduced the amount of FITC-dextran in the portal draining lymph node and through an LEC monolayer. We provide evidence that the mechanism by which oxLDL impacts lymphatic permeability is via a reduction in Prox1 expression which decreases lymphatic specific gene expression, impedes LEC metabolism and reorganizes the highly permeable lymphatic cell-cell junctions which are a defining feature of lymphatic capillaries. CONCLUSIONS: We identify oxLDL as a major contributor to decreased lymphatic permeability in the liver, a change which is consistent with decreased protein homeostasis and increased inflammation during chronic liver disease.


Subject(s)
Lipoproteins, LDL/metabolism , Liver/pathology , Lymphatic Vessels/pathology , Non-alcoholic Fatty Liver Disease/immunology , Animals , Diet, High-Fat/adverse effects , Disease Models, Animal , Homeodomain Proteins/metabolism , Humans , Intercellular Junctions/pathology , Liver/immunology , Lymphatic Vessels/cytology , Lymphatic Vessels/immunology , Male , Mice , Non-alcoholic Fatty Liver Disease/metabolism , Non-alcoholic Fatty Liver Disease/pathology , Permeability , Proteostasis/genetics , Proteostasis/immunology , RNA-Seq , Single-Cell Analysis , Tumor Suppressor Proteins/metabolism
15.
Genes Immun ; 21(5): 348-359, 2020 11.
Article in English | MEDLINE | ID: mdl-33116245

ABSTRACT

Clearance of acute infection with hepatitis C virus (HCV) is associated with the chr19q13.13 region containing the rs368234815 (TT/ΔG) polymorphism. We fine-mapped this region to detect possible causal variants that may contribute to HCV clearance. First, we performed sequencing of IFNL1-IFNL4 region in 64 individuals sampled according to rs368234815 genotype: TT/clearance (N = 16) and ΔG/persistent (N = 15) (genotype-outcome concordant) or TT/persistent (N = 19) and ΔG/clearance (N = 14) (discordant). 25 SNPs had a difference in counts of alternative allele >5 between clearance and persistence individuals. Then, we evaluated those markers in an association analysis of HCV clearance conditioning on rs368234815 in two groups of European (692 clearance/1 025 persistence) and African ancestry (320 clearance/1 515 persistence) individuals. 10/25 variants were associated (P < 0.05) in the conditioned analysis leaded by rs4803221 (P value = 4.9 × 10-04) and rs8099917 (P value = 5.5 × 10-04). In the European ancestry group, individuals with the haplotype rs368234815ΔG/rs4803221C were 1.7× more likely to clear than those with the rs368234815ΔG/rs4803221G haplotype (P value = 3.6 × 10-05). For another nearby SNP, the haplotype of rs368234815ΔG/rs8099917T was associated with HCV clearance compared to rs368234815ΔG/rs8099917G (OR: 1.6, P value = 1.8 × 10-04). We identified four possible causal variants: rs368234815, rs12982533, rs10612351 and rs4803221. Our results suggest a main signal of association represented by rs368234815, with contributions from rs4803221, and/or nearby SNPs including rs8099917.


Subject(s)
Hepatitis C/genetics , Interferons/genetics , Polymorphism, Single Nucleotide , Black People/genetics , Haplotypes , Hepatitis C/ethnology , Hepatitis C/pathology , Humans , Phenotype , White People/genetics
16.
PLoS One ; 15(7): e0236353, 2020.
Article in English | MEDLINE | ID: mdl-32730345

ABSTRACT

BACKGROUND & AIMS: Non-alcoholic steatohepatitis (NASH), a subtype of non-alcoholic fatty liver disease (NAFLD) that can lead to fibrosis, cirrhosis, and hepatocellular carcinoma, is characterized by hepatic inflammation. Despite evolving therapies aimed to ameliorate inflammation in NASH, the transcriptional changes that lead to inflammation progression in NAFLD remain poorly understood. The aim of this pilot study was to define transcriptional changes in early, non-fibrotic NAFLD using two independent biopsy-proven NAFLD cohorts. METHODS: We extracted RNA from liver tissue of 40 patients with biopsy-proven NAFLD based on NAFLD Activity Score (NAS) (23 patients with NAS ≤3, 17 with NAS ≥5) and 21 healthy controls, and we compared changes in expression of 594 genes involved in innate immune function. Using plasma from an independent cohort of 67 patients with NAFLD and 15 healthy controls, we validated the gene changes observed using a multiplex protein assay. RESULTS: Compared to healthy controls, NAFLD patients with NAS ≥5 had differential expression of 211 genes, while those with NAS ≤3 had differential expression of only 14 genes. Notably, osteopontin (SPP1) (3.74-fold in NAS ≤3, 8.28-fold in NAS ≥5) and CXCL10 (2.27-fold in NAS ≤3, 8.28-fold in NAS ≥5) gene expression were significantly upregulated with histologic progression of NAFLD. Plasma osteopontin (SPP1) and CXCL10 are significantly increased in the presence of NAFLD, regardless of histologic grade. In addition, the plasma levels of these two proteins distinguish clearly between the presence or absence of NAFLD (AUC>0.90). CONCLUSIONS: Osteopontin (SPP1) and CXCL10 are upregulated early in non-fibrotic NAFLD and may serve as valuable non-invasive biomarkers.


Subject(s)
Chemokine CXCL10/blood , Liver/metabolism , Non-alcoholic Fatty Liver Disease/blood , Osteopontin/blood , Adult , Case-Control Studies , Cohort Studies , Disease Progression , Female , Gene Expression Regulation , Humans , Liver/pathology , Male , Middle Aged , ROC Curve , Transcription, Genetic , Transcriptome/genetics
18.
Hepatology ; 71(6): 1940-1952, 2020 06.
Article in English | MEDLINE | ID: mdl-31553803

ABSTRACT

BACKGROUND AND AIMS: Epidemiological data on dietary risk factors for nonalcoholic fatty liver disease (NAFLD) from population-based studies, particularly in an ethnically diverse population, are scarce. We examined dietary factors in relation to NAFLD risk in African Americans, Japanese Americans, Latinos, native Hawaiians, and whites in the Multiethnic Cohort (MEC). APPROACH AND RESULTS: A nested case-control analysis was conducted within the MEC, a large prospective study with >215,000 older adult participants in Hawaii and California. NAFLD was identified using Medicare claims data, and controls were selected among participants without liver disease and individually matched to cases by birth year, sex, ethnicity, and length of Medicare enrollment. Diet was assessed at baseline through a validated quantitative food frequency questionnaire. Diet-NAFLD associations were quantified by odds ratios and 95% confidence intervals using multivariable conditional logistic regression. The study consisted of 2,974 NAFLD cases (518 with cirrhosis, 2,456 without cirrhosis) and 29,474 matched controls. Red meat (P trend = 0.010), processed red meat (P trend = 0.004), poultry (P trend = 0.005), and cholesterol (P trend = 0.005) intakes were positively associated with NAFLD, while dietary fiber intake (P trend = 0.003) was inversely associated with risk. Stronger associations were observed between red meat and cholesterol and NAFLD with cirrhosis than without cirrhosis (P heterogeneity ≤0.014). CONCLUSIONS: Dietary factors are independently associated with NAFLD and NAFLD-related cirrhosis in a multiethnic population. Decreasing the consumption of cholesterol, red and processed meat, and poultry and increasing consumption of fiber may reduce the risk for NAFLD and related advanced liver disease.


Subject(s)
Diet , Liver Cirrhosis , Non-alcoholic Fatty Liver Disease , Risk Assessment , Cholesterol, Dietary , Cohort Studies , Correlation of Data , Diet/ethnology , Diet/statistics & numerical data , Dietary Fiber , Ethnicity , Female , Food Preferences/ethnology , Humans , Liver Cirrhosis/diagnosis , Liver Cirrhosis/ethnology , Liver Cirrhosis/etiology , Male , Medicare/statistics & numerical data , Middle Aged , Non-alcoholic Fatty Liver Disease/diagnosis , Non-alcoholic Fatty Liver Disease/ethnology , Non-alcoholic Fatty Liver Disease/physiopathology , Red Meat , Risk Assessment/ethnology , Risk Assessment/statistics & numerical data , Risk Factors , United States/epidemiology
19.
Article in English | MEDLINE | ID: mdl-31871225

ABSTRACT

Host defense against invading pathogens within the liver is dominated by innate immunity. Natural killer (NK) cells have been implicated at all stages of hepatitis C virus (HCV) infection, from providing innate protection to contributing to treatment-induced clearance. Decreased NK cell levels, altered NK cell subset distribution, activation marker expression, and functional polarization toward a cytolytic phenotype are hallmarks of chronic HCV infection. Interferon α (IFN-α) is a potent activator of NK cells; therefore, it is not surprising that NK cell activation has been identified as a key factor associated with sustained virological response (SVR) to IFN-α-based therapies. Understanding the role of NK cells, macrophages, and other innate immune cells post-SVR remains paramount for prevention of disease pathogenesis and progression. Novel strategies to treat liver disease may be aimed at targeting these cells.


Subject(s)
Hepatitis C, Chronic/immunology , Killer Cells, Natural/immunology , Macrophages/immunology , Antiviral Agents/immunology , Antiviral Agents/therapeutic use , Hepacivirus/drug effects , Hepacivirus/immunology , Hepatitis C, Chronic/drug therapy , Humans , Interferon-alpha/immunology , Interferon-alpha/therapeutic use , Killer Cells, Natural/metabolism , Killer Cells, Natural/virology , Macrophages/metabolism , Macrophages/virology , Receptor Cross-Talk
20.
Front Immunol ; 10: 1036, 2019.
Article in English | MEDLINE | ID: mdl-31156626

ABSTRACT

Liver lymphatic vessels support liver function by draining interstitial fluid, cholesterol, fat, and immune cells for surveillance in the liver draining lymph node. Chronic liver disease is associated with increased inflammation and immune cell infiltrate. However, it is currently unknown if or how lymphatic vessels respond to increased inflammation and immune cell infiltrate in the liver during chronic disease. Here we demonstrate that lymphatic vessel abundance increases in patients with chronic liver disease and is associated with areas of fibrosis and immune cell infiltration. Using single-cell mRNA sequencing and multi-spectral immunofluorescence analysis we identified liver lymphatic endothelial cells and found that chronic liver disease results in lymphatic endothelial cells (LECs) that are in active cell cycle with increased expression of CCL21. Additionally, we found that LECs from patients with NASH adopt a transcriptional program associated with increased IL13 signaling. Moreover, we found that oxidized low density lipoprotein, associated with NASH pathogenesis, induced the transcription and protein production of IL13 in LECs both in vitro and in a mouse model. Finally, we show that oxidized low density lipoprotein reduced the transcription of PROX1 and decreased lymphatic stability. Together these data indicate that LECs are active participants in the liver, expanding in an attempt to maintain tissue homeostasis. However, when inflammatory signals, such as oxidized low density lipoprotein are increased, as in NASH, lymphatic function declines and liver homeostasis is impeded.


Subject(s)
Cell Differentiation , Endothelial Cells/metabolism , Hepatitis C, Chronic/metabolism , Liver/pathology , Non-alcoholic Fatty Liver Disease/metabolism , Adult , Aged , Aged, 80 and over , Animals , Chronic Disease , Female , Hepatitis C, Chronic/pathology , Humans , Lipoproteins, LDL/pharmacology , Lymphatic Vessels/pathology , Male , Mice , Mice, Inbred C57BL , Middle Aged , Non-alcoholic Fatty Liver Disease/chemically induced , Non-alcoholic Fatty Liver Disease/pathology , Sequence Analysis, RNA , Single-Cell Analysis
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