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1.
Int J Mol Sci ; 25(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38732052

RESUMO

Fatty acid desaturase 1 (FADS1) is a rate-limiting enzyme in long-chain polyunsaturated fatty acid (LCPUFA) synthesis. Reduced activity of FADS1 was observed in metabolic dysfunction-associated steatotic liver disease (MASLD). The aim of this study was to determine whether adeno-associated virus serotype 8 (AAV8) mediated hepatocyte-specific overexpression of Fads1 (AAV8-Fads1) attenuates western diet-induced metabolic phenotypes in a rat model. Male weanling Sprague-Dawley rats were fed with a chow diet, or low-fat high-fructose (LFHFr) or high-fat high-fructose diet (HFHFr) ad libitum for 8 weeks. Metabolic phenotypes were evaluated at the endpoint. AAV8-Fads1 injection restored hepatic FADS1 protein levels in both LFHFr and HFHFr-fed rats. While AAV8-Fads1 injection led to improved glucose tolerance and insulin signaling in LFHFr-fed rats, it significantly reduced plasma triglyceride (by ~50%) and hepatic cholesterol levels (by ~25%) in HFHFr-fed rats. Hepatic lipidomics analysis showed that FADS1 activity was rescued by AAV8-FADS1 in HFHFr-fed rats, as shown by the restored arachidonic acid (AA)/dihomo-γ-linolenic acid (DGLA) ratio, and that was associated with reduced monounsaturated fatty acid (MUFA). Our data suggest that the beneficial role of AAV8-Fads1 is likely mediated by the inhibition of fatty acid re-esterification. FADS1 is a promising therapeutic target for MASLD in a diet-dependent manner.


Assuntos
Dessaturase de Ácido Graxo Delta-5 , Dieta Ocidental , Ácidos Graxos Dessaturases , Hepatócitos , Ratos Sprague-Dawley , Animais , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Dessaturases/genética , Masculino , Ratos , Dessaturase de Ácido Graxo Delta-5/metabolismo , Dieta Ocidental/efeitos adversos , Hepatócitos/metabolismo , Fenótipo , Modelos Animais de Doenças , Dependovirus/genética , Fígado/metabolismo , Triglicerídeos/metabolismo , Frutose/metabolismo
2.
Am J Pathol ; 194(1): 71-84, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37925018

RESUMO

Alcohol-associated liver disease (ALD) is a serious public health problem with limited pharmacologic options. The goal of the current study was to investigate the efficacy of pharmacologic inhibition of soluble epoxide hydrolase (sEH), an enzyme involved in lipid metabolism, in experimental ALD, and to examine the underlying mechanisms. C57BL/6J male mice were subjected to acute-on-chronic ethanol (EtOH) feeding with or without the sEH inhibitor 4-[[trans-4-[[[[4-trifluoromethoxy phenyl]amino]carbonyl]-amino]cyclohexyl]oxy]-benzoic acid (TUCB). Liver injury was assessed by multiple end points. Liver epoxy fatty acids and dihydroxy fatty acids were measured by targeted metabolomics. Whole-liver RNA sequencing was performed, and free modified RNA bases were measured by mass spectrometry. EtOH-induced liver injury was ameliorated by TUCB treatment as evidenced by reduced plasma alanine aminotransferase levels and was associated with attenuated alcohol-induced endoplasmic reticulum stress, reduced neutrophil infiltration, and increased numbers of hepatic M2 macrophages. TUCB altered liver epoxy and dihydroxy fatty acids and led to a unique hepatic transcriptional profile characterized by decreased expression of genes involved in apoptosis, inflammation, fibrosis, and carcinogenesis. Several modified RNA bases were robustly changed by TUCB, including N6-methyladenosine and 2-methylthio-N6-threonylcarbamoyladenosine. These findings show the beneficial effects of sEH inhibition by TUCB in experimental EtOH-induced liver injury, warranting further mechanistic studies to explore the underlying mechanisms, and highlighting the translational potential of sEH as a drug target for this disease.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Hepatopatias Alcoólicas , Camundongos , Animais , Masculino , Epóxido Hidrolases/genética , Epóxido Hidrolases/metabolismo , Transcriptoma , Camundongos Endogâmicos C57BL , Hepatopatias Alcoólicas/genética , Ácidos Graxos , Etanol , RNA
3.
Hepatol Commun ; 7(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37994498

RESUMO

BACKGROUND: Severe alcoholic hepatitis (AH) has a high short-term mortality rate. The MELD assesses disease severity and mortality; however, it is not specific for AH. We screened plasma samples from patients with severe AH for biomarkers of multiple pathological processes and identified predictors of short-term mortality. METHODS: Plasma was collected at baseline from 85 patients with severe AH (MELD≥20, Maddrey's discriminant function≥32) enrolled in the Defeat Alcoholic Steatohepatitis clinical trial (investigating IL-1 receptor antagonist+pentoxifylline+zinc vs. methylprednisolone+placebo). Samples were analyzed for 43 biomarkers and the markers' association with 28- and 90-day mortalities was assessed. RESULTS: Thirty-one (36.5%) patients died during the 90-day follow-up with similar ratios in the treatment groups. Eight biomarkers showed an association with mortality. IL-6, IL-22, interferon-α2, soluble TNF receptor 1, lipocalin-2, and α-fetoprotein levels were associated with 28-day mortality, while IL-6, IL-13, and endotoxin levels with 90-day mortality. In multivariable Cox regression, encephalopathy, lipocalin-2, and α-fetoprotein levels were independent predictors of 28-day mortality, and IL-6, IL-13, international normalized ratio levels, and age were independent predictors of 90-day mortality. The combination of IL-13 and age had superior performance in predicting 90-day mortality compared with MELD in the total cohort and the individual treatment groups. CONCLUSIONS: We identified predictors of short-term mortality in a cohort exclusively involving patients with severe AH. We created a composite score of IL-13 and age that predicts 90-day mortality regardless of the treatment type with a performance superior to MELD in severe AH.


Assuntos
Fatores Etários , Hepatite Alcoólica , Interleucina-13 , Humanos , alfa-Fetoproteínas , Biomarcadores/sangue , Hepatite Alcoólica/mortalidade , Interleucina-13/sangue , Interleucina-6 , Lipocalina-2
4.
Biology (Basel) ; 12(10)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37887031

RESUMO

BACKGROUND: Cyclic nucleotides are second messengers, which play significant roles in numerous biological processes. Previous work has shown that cAMP and cGMP signaling regulates various pathways in liver cells, including Kupffer cells, hepatocytes, hepatic stellate cells, and cellular components of hepatic sinusoids. Importantly, it has been shown that cAMP levels and enzymes involved in cAMP homeostasis are affected by alcohol. Although the role of cyclic nucleotide signaling is strongly implicated in several pathological pathways in liver diseases, studies describing the changes in genes regulating cyclic nucleotide metabolism in ALD are lacking. METHODS: Male C57B/6 mice were used in an intragastric model of alcohol-associated steatohepatitis (ASH). Liver injury, inflammation, and fibrogenesis were evaluated by measuring plasma levels of injury markers, liver tissue cytokines, and gene expression analyses. Liver transcriptome analysis was performed to examine the effects of alcohol on regulators of cyclic AMP and GMP levels and signaling. cAMP and cGMP levels were measured in mouse livers as well as in livers from healthy human donors and patients with alcohol-associated hepatitis (AH). RESULTS: Our results show significant changes in several phosphodiesterases (PDEs) with specificity to degrade cAMP (Pde4a, Pde4d, and Pde8a) and cGMP (Pde5a, Pde6d, and Pde9a), as well as dual-specificity PDEs (Pde1a and Pde10a) in ASH mouse livers. Adenylyl cyclases (ACs) 7 and 9, which are responsible for cAMP generation, were also affected by alcohol. Importantly, adenosine receptor 1, which has been implicated in the pathogenesis of liver diseases, was significantly increased by alcohol. Adrenoceptors 1 and 3 (Adrb), which couple with stimulatory G protein to regulate cAMP and cGMP signaling, were significantly decreased. Additionally, beta arrestin 2, which interacts with cAMP-specific PDE4D to desensitize G-protein-coupled receptor to generate cAMP, was significantly increased by alcohol. Notably, we observed that cAMP levels are much higher than cGMP levels in the livers of humans and mice; however, alcohol affected them differently. Specifically, cGMP levels were higher in patients with AH and ASH mice livers compared with controls. As expected, these changes in liver cyclic nucleotide signaling were associated with increased inflammation, steatosis, apoptosis, and fibrogenesis. CONCLUSIONS: These data strongly implicate dysregulated cAMP and cGMP signaling in the pathogenesis of ASH. Future studies to identify changes in these regulators in a cell-specific manner could lead to the development of novel targeted therapies for ASH.

5.
Environ Res ; 221: 115228, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36610539

RESUMO

While occupational exposures to volatile organic compounds (VOCs) have been linked to steatohepatitis and liver cancer in industrial workers, recent findings have also positively correlated low-dose, residential VOC exposures with liver injury markers. VOC sources are numerous; factors including biological make up (sex), socio-cultural constructs (gender, race) and lifestyle (smoking) can influence both VOC exposure levels and disease outcomes. Therefore, the current study's objective is to investigate how sex and race influence associations between residential VOC exposures and liver injury markers particularly in smokers vs. nonsmokers. Subjects (n = 663) were recruited from residential neighborhoods; informed consent was obtained. Exposure biomarkers included 16 urinary VOC metabolites. Serological disease biomarkers included liver enzymes, direct bilirubin, and hepatocyte death markers (cytokeratin K18). Pearson correlations and generalized linear models were conducted. Models were adjusted for common liver-related confounders and interaction terms. The study population constituted approximately 60% females (n = 401) and 40% males (n = 262), and a higher percent of males were smokers and/or frequent drinkers. Both sexes had a higher percent of White (75% females, 82% males) vs. Black individuals. Positive associations were identified for metabolites of acrolein, acrylamide, acrylonitrile, butadiene, crotonaldehyde, and styrene with alkaline phosphatase (ALP), a biomarker for cholestatic injury; and for the benzene metabolite with bilirubin; only in females. These associations were retained in female smokers. Similar associations were also observed between these metabolites and ALP only in White individuals (n = 514). In Black individuals (n = 114), the styrene metabolite was positively associated with aspartate transaminase. Interaction models indicated that positive associations for acrylamide/crotonaldehyde metabolites with ALP in females were dose-dependent. Most VOC associations with K18 markers were negative in this residential population. Overall, the findings demonstrated that biological sex, race, and smoking status influence VOC effects on liver injury and underscored the role of biological-social-lifestyle factor(s) interactions when addressing air pollution-related health disparities.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Masculino , Humanos , Feminino , Compostos Orgânicos Voláteis/análise , Poluentes Atmosféricos/análise , Fígado/química , Biomarcadores/urina , Acrilamidas , Estirenos
6.
Cell Rep ; 38(13): 110560, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35354041

RESUMO

It is not clear how the complex interactions between diet and intestinal immune cells protect the gut from infection. Neutral ceramidase (NcDase) plays a critical role in digesting dietary sphingolipids. We find that NcDase is an essential factor that controls intestinal immune cell dynamics. Mice lacking NcDase have reduced cluster of differentiation (CD) 8αß+ T cells and interferon (IFN)-γ+ T cells and increased macrophages in the intestine and fail to clear bacteria after Citrobacter rodentium infection. Mechanistically, cellular NcDase or extracellular vesicle (EV)-related NcDase generates sphingosine, which promotes macrophage-driven Th1 immunity. Loss of NcDase influences sphingosine-controlled glycolytic metabolism in macrophages, which regulates the bactericidal activity of macrophages. Importantly, administration of dietary sphingomyelin and genetic deletion or pharmacological inhibition of SphK1 can protect against C. rodentium infection. Our findings demonstrate that sphingosine profoundly alters macrophage glycolytic metabolism, leading to intestinal macrophage activation and T cell polarization, which prevent pathogen colonization of the gut.


Assuntos
Ceramidase Neutra , Esfingosina , Animais , Homeostase , Intestino Delgado/metabolismo , Macrófagos/metabolismo , Camundongos , Ceramidase Neutra/genética , Ceramidase Neutra/metabolismo , Esfingosina/metabolismo
7.
Oncogene ; 41(16): 2287-2302, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35246617

RESUMO

RORγt is a master regulator of Th17 cells. Despite evidence linking RORγt deficiency/inhibition with metastatic thymic T cell lymphomas, the role of RORγt in lymphoma metabolism is unknown. Chronic alcohol consumption plays a causal role in many human cancers. The risk of T cell lymphoma remains unclear in humans with alcohol use disorders (AUD) after chronic RORγt inhibition. Here we demonstrated that alcohol consumption accelerates RORγt deficiency-induced lymphomagenesis. Loss of RORγt signaling in the thymus promotes aerobic glycolysis and glutaminolysis and increases allocation of glutamine carbon into lipids. Importantly, alcohol consumption results in a shift from aerobic glycolysis to glutaminolysis. Both RORγt deficiency- and alcohol-induced metabolic alterations are mediated by c-Myc, as silencing of c-Myc decreases the effects of alcohol consumption and RORγt deficiency on glutaminolysis, biosynthesis, and tumor growth in vivo. The ethanol-mediated c-Myc activation coupled with increased glutaminolysis underscore the critical role of RORγt-Myc signaling and translation in lymphoma.


Assuntos
Alcoolismo , Linfoma , Etanol/toxicidade , Humanos , Linfoma/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transdução de Sinais
8.
J Depress Anxiety ; 11(5)2022.
Artigo em Inglês | MEDLINE | ID: mdl-37583369

RESUMO

Objectives: To examine the prevalence and treatment utilization of patients diagnosed with Depression and Anxiety Disorders (DAD) based on Kentucky Medicaid 2012-2019 datasets. Methods: The study was based on Kentucky Medicaid claims data from 2012 through 2019 for patients 14 years and older. We constructed yearly patient-level databases using ICD_9 CM and ICD_10 CM codes to identify the patients with DAD, using the Current Procedure Terminology (CPT) codes to identify individual psychotherapy and group psychotherapy and using the National drug codes to categorize pharmacotherapy. Based on these data, we constructed summary tables that reflected the trends in prevalence of DAD across eight Kentucky Medicaid regions and for different demographic subgroups. Next, we implemented logistic regression on the constructed yearly patient-level data to formally assess the impact of risk factors and treatments on the prevalence of DAD. The potential risk factors included age, gender, race/ethnicity, geographic characteristics, comorbidities such as alcohol use disorder and tobacco use. Results: The prevalence of DAD increased from 30.84% in 2012 to 36.04% in 2019. The prevalence of DAD was significantly higher in patients with the following characteristics: non-Hispanic white, females, aged between 45 and 54 years old, living in rural areas, having alcohol use disorder, and using tobaccos. Other than 2013, the utilization of pharmacotherapy maintained at about 62%. The utilization of psychotherapy increased over years from 24.4% in 2012 to 36.5% in 2019. Overall, the utilization of any treatment slightly increased from 70.9% in 2012 to 73.3% in 2019 except a drastic decline in 2013 due to the reduction of benzodiazepine prescription. Patients being whites, females, and living in rural areas were more likely to use pharmacotherapy, and patients living in rural areas were less likely to use psychotherapy than those residing in urban areas. Conclusion: The prevalence of DAD has increased over time from 2012 to 2019. The utilization of pharmacotherapy maintained at 62% over eight years except 2013, and the utilization of psychotherapy has steadily increased over time.

9.
Artigo em Inglês | MEDLINE | ID: mdl-36683779

RESUMO

Alcohol use is the leading substance use in the United States. Persons with alcohol use disorder (AUD) face enormous health consequences and family problems. Analysis of Medicaid enrollee data is critical to understand different aspects of AUD and the treatment utilization for patients with AUD. Yearly patient-level data were constructed from the Kentucky 2012-2019 Medicaid claims data. ICD-9-CM and ICD-10-CM codes were used to identify patients with AUD and their comorbid conditions, the 11-digit National Drug Codes were used to identify medication treatments, and procedure codes were used to identify psychosocial and behavioral therapies. Logistic regression models were used to examine factors that were associated with AUD prevalence and AUD treatments. The prevalence of AUD trended up over time. Patients living in metro areas, between ages 45-54, having mental disorders, tobacco use, and with a family history of alcoholism had significantly higher rates of AUD. About 60% of patients diagnosed with AUD had major depressive disorder or anxiety. The treatment utilization for AUD also trended up from 2012 to 2019; however, it was still lower than 25% in 2019. Pharmacological treatments were used in only 2.89% of AUD cases in 2012, which increased to 8.13% in 2019. Psychosocial treatments were used in only 1.59% of AUD cases in 2012 that increased to 18.95% in 2019. The prevalence of AUD trended up over years. However, the treatment utilization for AUD was lower than 25%, even as of 2019. There is an urgent need for comprehensive, evidence-based, personalized AUD treatments.

10.
Toxicol Sci ; 185(1): 50-63, 2021 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-34668566

RESUMO

Occupational exposures to volatile organic compounds (VOCs) have been associated with numerous health complications including steatohepatitis and liver cancer. However, the potential impact of environmental/residential VOC exposures on liver health and function is largely unknown. To address this knowledge gap, the objective of this cross-sectional study is to investigate associations between VOCs and liver injury biomarkers in community residents. Subjects were recruited from six Louisville neighborhoods, and informed consent was obtained. Exposure biomarkers included 16 creatinine-adjusted urinary metabolites corresponding to 12 parent VOCs. Serological disease biomarkers measured included cytokertain-18 (K18 M65 and M30), liver enzymes, and direct bilirubin. Associations between exposure and disease biomarkers were assessed using generalized linear models. Smoking status was confirmed through urinary cotinine levels. The population comprised of approximately 60% females and 40% males; White persons accounted 78% of the population; with more nonsmokers (n = 413) than smokers (n = 250). When compared with nonsmokers, males (45%) and Black persons (26%) were more likely to be smokers. In the overall population, metabolites of acrolein, acrylonitrile, acrylamide, 1,3-butadiene, crotonaldehyde, styrene, and xylene were positively associated with alkaline phosphatase. These associations persisted in smokers, with the exception of crotonaldehyde, and addition of N,N-dimethylformamide and propylene oxide metabolites. Although no positive associations were observed for K18 M30, the benzene metabolite was positively associated with bilirubin, irrespective of smoking status. Taken together, the results demonstrated that selected VOCs were positively associated with liver injury biomarkers. These findings will enable better risk assessment and identification of populations vulnerable to liver disease.


Assuntos
Compostos Orgânicos Voláteis , Biomarcadores/urina , Estudos Transversais , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Fígado/metabolismo , Masculino , Compostos Orgânicos Voláteis/metabolismo
11.
Int J Mol Sci ; 22(10)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34065028

RESUMO

BACKGROUND: High-level occupational vinyl chloride (VC) exposures have been associated with hepatic hemangiosarcoma, which typically develops following a long latency period. Although VC is genotoxic, a more comprehensive mode of action has not been determined and diagnostic biomarkers have not been established. The purpose of this study is to address these knowledge gaps through plasma metabolomics. METHODS: Plasma samples from polyvinyl chloride polymerization workers who developed hemangiosarcoma (cases, n = 15) and VC exposure-matched controls (n = 17) underwent metabolomic analysis. Random forest and bioinformatic analyses were performed. RESULTS: Cases and controls had similar demographics and routine liver biochemistries. Mass spectroscopy identified 606 known metabolites. Random forest analysis had an 82% predictive accuracy for group classification. 60 metabolites were significantly increased and 44 were decreased vs. controls. Taurocholate, bradykinin and fibrin degradation product 2 were up-regulated by greater than 80-fold. The naturally occurring anti-angiogenic phenol, 4-hydroxybenzyl alcohol, was down-regulated 5-fold. Top affected ontologies involved: (i) metabolism of bile acids, taurine, cholesterol, fatty acids and amino acids; (ii) inflammation and oxidative stress; and (iii) nicotinic cholinergic signaling. CONCLUSIONS: The plasma metabolome was differentially regulated in polyvinyl chloride workers who developed hepatic hemangiosarcoma. Ontologies potentially involved in hemangiosarcoma pathogenesis and candidate biomarkers were identified.


Assuntos
Biomarcadores/sangue , Hemangiossarcoma/diagnóstico , Neoplasias Hepáticas/diagnóstico , Metaboloma , Doenças Profissionais/diagnóstico , Exposição Ocupacional/efeitos adversos , Cloreto de Polivinila/efeitos adversos , Estudos de Casos e Controles , Hemangiossarcoma/sangue , Hemangiossarcoma/induzido quimicamente , Hemangiossarcoma/epidemiologia , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/sangue , Doenças Profissionais/induzido quimicamente , Doenças Profissionais/epidemiologia , Estados Unidos/epidemiologia
12.
Mol Ther ; 29(8): 2424-2440, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-33984520

RESUMO

Lung inflammation is a hallmark of coronavirus disease 2019 (COVID-19). In this study, we show that mice develop inflamed lung tissue after being administered exosomes released from the lung epithelial cells exposed to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Nsp12 and Nsp13 (exosomesNsp12Nsp13). Mechanistically, we show that exosomesNsp12Nsp13 are taken up by lung macrophages, leading to activation of nuclear factor κB (NF-κB) and the subsequent induction of an array of inflammatory cytokines. Induction of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1ß from exosomesNsp12Nsp13-activated lung macrophages contributes to inducing apoptosis in lung epithelial cells. Induction of exosomesNsp12Nsp13-mediated lung inflammation was abolished with ginger exosome-like nanoparticle (GELN) microRNA (miRNA aly-miR396a-5p. The role of GELNs in inhibition of the SARS-CoV-2-induced cytopathic effect (CPE) was further demonstrated via GELN aly-miR396a-5p- and rlcv-miR-rL1-28-3p-mediated inhibition of expression of Nsp12 and spike genes, respectively. Taken together, our results reveal exosomesNsp12Nsp13 as potentially important contributors to the development of lung inflammation, and GELNs are a potential therapeutic agent to treat COVID-19.


Assuntos
COVID-19/metabolismo , Exossomos/metabolismo , MicroRNAs/metabolismo , Plantas/metabolismo , Pneumonia/metabolismo , Células A549 , Animais , Linhagem Celular , Linhagem Celular Tumoral , Chlorocebus aethiops , Citocinas/metabolismo , Células Epiteliais/metabolismo , Humanos , Interleucina-6/metabolismo , Macrófagos Alveolares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , SARS-CoV-2/patogenicidade , Fator de Necrose Tumoral alfa/metabolismo , Células U937 , Células Vero
13.
Nat Commun ; 12(1): 213, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33431899

RESUMO

High-fat diet (HFD) decreases insulin sensitivity. How high-fat diet causes insulin resistance is largely unknown. Here, we show that lean mice become insulin resistant after being administered exosomes isolated from the feces of obese mice fed a HFD or from patients with type II diabetes. HFD altered the lipid composition of exosomes from predominantly phosphatidylethanolamine (PE) in exosomes from lean animals (L-Exo) to phosphatidylcholine (PC) in exosomes from obese animals (H-Exo). Mechanistically, we show that intestinal H-Exo is taken up by macrophages and hepatocytes, leading to inhibition of the insulin signaling pathway. Moreover, exosome-derived PC binds to and activates AhR, leading to inhibition of the expression of genes essential for activation of the insulin signaling pathway, including IRS-2, and its downstream genes PI3K and Akt. Together, our results reveal HFD-induced exosomes as potential contributors to the development of insulin resistance. Intestinal exosomes thus have potential as broad therapeutic targets.


Assuntos
Dieta Hiperlipídica , Exossomos/metabolismo , Resistência à Insulina/genética , Fosfatidilcolinas/metabolismo , Regulação para Cima/genética , Tecido Adiposo/metabolismo , Animais , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Dislipidemias/complicações , Dislipidemias/genética , Dislipidemias/patologia , Células Epiteliais/metabolismo , Fígado Gorduroso/complicações , Fígado Gorduroso/genética , Fígado Gorduroso/patologia , Fezes , Regulação da Expressão Gênica , Intolerância à Glucose , Proteínas de Fluorescência Verde/metabolismo , Humanos , Insulina/metabolismo , Interleucina-6/sangue , Intestinos/citologia , Lipídeos/química , Fígado/metabolismo , Fígado/patologia , Ativação de Macrófagos , Camundongos Endogâmicos C57BL , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais , Tetraspanina 30/metabolismo , Fator de Necrose Tumoral alfa/sangue
14.
J Acquir Immune Defic Syndr ; 86(1): 128-137, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33093334

RESUMO

BACKGROUND: Chronic immune activation and CD4 T cell depletion are significant pathogenic features of HIV infection. Expression of Fas ligand (FasL), a key mediator of activation-induced cell death in T cells, is elevated in people living with HIV-1 infection (PLWH). However, the epigenetic mechanisms underlying the enhanced induction of FasL expression in CD4 T lymphocytes in PLWH are not completely elucidated. Hence, the current work examined the effect of HIV infection on FasL promoter-associated histone modifications and transcriptional regulation in CD4 T lymphocytes in PLWH. METHOD: Flow cytometric analysis was performed to examine the Fas-FasL expression on total CD4 T cells and naïve/memory CD4 T cell subsets. Epigenetic FasL promoter histone modifications were investigated by chromatin immunoprecipitation-quantitative real-time polymerase chain reaction analysis using freshly isolated total CD4 T lymphocytes from HIV-1 infected and noninfected individuals. RESULTS: All naïve/memory CD4 T cell subsets from PLWH showed markedly greater frequency of FasL expression. Notably, examination of functional outcome of FasL/Fas co-expression demonstrated the preferential susceptibility of Tcm and Tem subsets to activation-induced apoptosis. Importantly, these CD4 T cells collectively demonstrated a distinct FasL promoter histone profile involving a coordinated cross-talk between histone H3 modifications leading to enhanced FasL gene expression. Specifically, levels of transcriptionally permissive histone H3K4-trimethylation (H3K4Me3) and histone H3K9-acetylation (H3K9Ac) were increased, with a concomitant decrease in the repressive H3K9-trimethylation (H3K9Me3). CONCLUSION: The present work demonstrates that epigenetic mechanisms involving promoter-histone modifications regulate transcriptional competence and FasL expression in CD4 T cells from PLWH and render them susceptible to activation-induced cell death.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Morte Celular , Epigênese Genética , Proteína Ligante Fas/metabolismo , Infecções por HIV/imunologia , Adulto , Proteína Ligante Fas/genética , Feminino , Regulação da Expressão Gênica , HIV-1/fisiologia , Histonas/metabolismo , Humanos , Ativação Linfocitária , Masculino , Metilação , Pessoa de Meia-Idade , Fatores de Transcrição
15.
Hepatology ; 73(3): 901-919, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33185911

RESUMO

BACKGROUND AND AIMS: Nonalcoholic steatohepatitis (NASH) is associated with obesity and an increased risk for liver cirrhosis and cancer. Neutral ceramidase (NcDase), which is highly expressed in the intestinal brush border of the small intestine, plays a critical role in digesting dietary sphingolipids (ceramide) to regulate the balance of sphingosine and free fatty acids. It remains unresolved whether obesity-associated alteration of NcDase contributes to the manifestation of NASH. Here, we revealed that NcDase deficiency in murine models of NASH prevents hepatic inflammation and fibrosis but not steatosis. APPROACH AND RESULTS: NcDase-/- mice display reduced stearoyl-CoA desaturase (SCD) 1 expression with a compositional decrease of monounsaturated fatty acids (MUFAs) under the different dietary conditions. We further found that NcDase is a functional regulator of intestinal B cells and influences the abundance and quality of the secretory IgA response toward commensal bacteria. Analysis of composition of the gut microbiota found that Clostridiales colonization was increased in NcDase-/- mice. The colonization of germ-free mice with gut microbiota from NcDase-/- mice resulted in a greater decrease in the expression of SCD1 and the level of MUFAs in the liver relative to gut microbiota from wild-type littermates, which are associated with the alternation of IgA-bound bacteria, including increase of Ruminococcaceae and reduction of Desulfovibrio. Mechanistically, NcDase is a crucial link that controls the expression of SCD1 and MUFA-mediated activation of the Wnt/ß-catenin. Very importantly, our experiments further demonstrated that Wnt3a stimulation can enhance the activity of NcDase in hepatocytes. CONCLUSIONS: Thus, the NcDase-SCD1-Wnt feedback loop promotes the diet-induced steatohepatitis and fibrosis through the regulation of intestinal IgA+ immune cells.


Assuntos
Linfócitos B/fisiologia , Ácidos Graxos Monoinsaturados/metabolismo , Imunoglobulina A/metabolismo , Mucosa Intestinal/metabolismo , Ceramidase Neutra/fisiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Animais , Linfócitos B/metabolismo , Modelos Animais de Doenças , Microbioma Gastrointestinal/imunologia , Mucosa Intestinal/citologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ceramidase Neutra/deficiência , Ceramidase Neutra/metabolismo , Obesidade/metabolismo
16.
Contemp Clin Trials ; 96: 106094, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32739495

RESUMO

BACKGROUND/AIMS: Despite high mortality of alcohol-associated hepatitis, there has been limited advancement in treatment strategies. Defeat Alcoholic Steatohepatitis (DASH) is a multicenter, randomized, double-blind controlled trial whose primary objective was to evaluate the safety and efficacy of a novel combination of 3 drugs targeting different perturbations in AH. METHODS: Severe AH was diagnosed by liver biopsy or clinical and biochemical criteria and model for end stage liver disease (MELD) score ≥ 20 stratified by MELD scores (20-25 and ≥ 26) and randomized to a combination of an interleukin receptor 1 antagonist, Anakinra(100 mg daily for 14 days) to suppress acute inflammation, pentoxifylline (400 mg three times a day for 28 days) to prevent hepatorenal syndrome, and zinc sulfate (220 mg orally once daily for 6 months) or the standard of care therapy including methylprednisolone 32 mg orally once daily for 28 days. The primary efficacy outcome was the unadjusted log-rank test of the Kaplan-Meier survival estimates for the two treatment groups at 180 days. RESULTS: Between July 2012 to March 2018, 500 subjects with severe AH were screened of which 104 subjects were enrolled with MELD score of 25.6 ± 3.2 (20.0-35.0) in the investigational arm and 25.8 ± 4.5 (20.0-40.0) in the standard of care arm. Causes of screen failures included not meeting eligibility criteria (n = 347), declining to participate (n = 39), and other reasons (n = 10). CONCLUSIONS: Data from the DASH consortium studies will determine if a combination of drugs targeting multiple mechanisms of injury in the severe AH will improve clinical outcomes.


Assuntos
Doença Hepática Terminal , Fígado Gorduroso Alcoólico , Hepatite Alcoólica , Fígado Gorduroso Alcoólico/tratamento farmacológico , Hepatite Alcoólica/tratamento farmacológico , Humanos , Índice de Gravidade de Doença , Resultado do Tratamento
17.
Evol Bioinform Online ; 16: 1176934320913338, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32313420

RESUMO

The analysis of plasma microRNAs (miRNAs) has been widely used as a method for finding potential biomarkers for human diseases, especially those with a link to cancer. Methods of analyzing plasma miRNA have been thoroughly discussed from sample extraction to data modeling. However, some issues exist within the process that have rarely been talked about. Rice et al. discussed some issues in plasma miRNA studies, such as the lack of standard methodology including the use of different cycle threshold, time to plasma extraction, among others. These issues can lead to inconsistent data, and thus impact the result and assay reproducibility. Other external issues, such as batch effect and operator effect, may also indirectly impact the statistical analysis. Here, we discuss issues in plasma miRNA studies from a statistical point of view. The interaction effect of different ways of calculating fold-change, the choice of housekeeping genes, and methods of normalization are among the issues we discuss, with data demonstrations. P values are calculated and compared to determine the effect of those issues on statistical conclusions. Statistical methods such as analysis of variance and analysis of covariance are crucial in the analysis of miRNA but investigators are often confused about them; therefore, a brief explanation of these statistical methods is also included. In addition, 3-group classification is discussed, as it is often challenging, compared with 2-group classification.

18.
Analyst ; 144(14): 4331-4341, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31192319

RESUMO

The diverse characteristics and large number of entities make metabolite separation challenging in metabolomics. To date, there is not a singular instrument capable of analyzing all types of metabolites. In order to achieve a better separation for higher peak capacity and accurate metabolite identification and quantification, we integrated GC × GC-MS and parallel 2DLC-MS for analysis of polar metabolites. To test the performance of the developed system, 13 rats were fed different diets to form two animal groups. Polar metabolites extracted from rat livers were analyzed by GC × GC-MS, parallel 2DLC-MS (-) and parallel 2DLC-MS (+), respectively. By integrating all data together, 58 metabolites were detected with significant change in their abundance levels between groups (p≤ 0.05). Of the 58 metabolites, three metabolites were detected in two platforms and two in all three platforms. Manual examination showed that discrepancy of metabolite regulation measured by different platforms was mainly caused by the poor shape of chromatographic peaks resulting from low instrument response. Pathway analysis demonstrated that integrating the results from multiple platforms increased the confidence of metabolic pathway assignment.


Assuntos
Metaboloma , Metabolômica/métodos , Animais , Cromatografia Líquida/métodos , Dieta , Cromatografia Gasosa-Espectrometria de Massas/métodos , Fígado/química , Masculino , Ratos Sprague-Dawley
19.
Am J Pathol ; 187(10): 2232-2245, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28923202

RESUMO

Alcoholic liver disease is a major human health problem leading to significant morbidity and mortality in the United States and worldwide. Dietary fat plays an important role in alcoholic liver disease pathogenesis. Herein, we tested the hypothesis that a combination of ethanol and a diet rich in linoleic acid (LA) leads to the increased production of oxidized LA metabolites (OXLAMs), specifically 9- and 13-hydroxyoctadecadienoic acids (HODEs), which contribute to a hepatic proinflammatory response exacerbating liver injury. Mice were fed unsaturated (with a high LA content) or saturated fat diets (USF and SF, respectively) with or without ethanol for 10 days, followed by a single binge of ethanol. Compared to SF+ethanol, mice fed USF+ethanol had elevated plasma alanine transaminase levels, enhanced hepatic steatosis, oxidative stress, and inflammation. Plasma and liver levels of 9- and 13-HODEs were increased in response to USF+ethanol feeding. We demonstrated that primarily 9-HODE, but not 13-HODE, induced the expression of several proinflammatory cytokines in vitro in RAW264.7 macrophages. Finally, deficiency of arachidonate 15-lipoxygenase, a major enzyme involved in LA oxidation and OXLAM production, attenuated liver injury and inflammation caused by USF+ethanol feeding but had no effect on hepatic steatosis. This study demonstrates that OXLAM-mediated induction of a proinflammatory response in macrophages is one of the potential mechanisms underlying the progression from alcohol-induced steatosis to alcoholic steatohepatitis.


Assuntos
Gorduras na Dieta/efeitos adversos , Inflamação/patologia , Ácido Linoleico/efeitos adversos , Fígado/metabolismo , Fígado/patologia , Animais , Araquidonato 15-Lipoxigenase/metabolismo , Consumo Excessivo de Bebidas Alcoólicas , Composição Corporal , Citocinas/metabolismo , Modelos Animais de Doenças , Etanol , Ácidos Linoleicos/metabolismo , Ácidos Linoleicos Conjugados/metabolismo , Macrófagos/metabolismo , Metaboloma , Camundongos , Camundongos Endogâmicos C57BL , Oxirredução , Estresse Oxidativo , Células RAW 264.7
20.
Neuropharmacology ; 125: 376-385, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28807677

RESUMO

It is increasingly evident that alcohol-induced, gut-mediated peripheral endotoxemia plays a significant role in glial cell activation and neuro-inflammation. Using a mouse model of chronic alcohol feeding, we examined the causal role of endotoxin- and cytokine-responsive Pde4 subfamily b (Pde4b) expression in alcohol-induced neuro-inflammation. Both pharmacologic and genetic approaches were used to determine the regulatory role of Pde4b. In C57Bl/6 wild type (WT) alcohol fed (WT-AF) animals, alcohol significantly induced peripheral endotoxemia and Pde4b expression in brain tissue, accompanied by a decrease in cAMP levels. Further, along with Pde4b, there was a robust activation of astrocytes and microglia accompanied by significant increases in the inflammatory cytokines (Tnfα, Il-1ß, Mcp-1 and Il-17) and the generalized inflammatory marker Cox-2. At the cellular level, alcohol and inflammatory mediators, particularly LPS, Tnfα and Hmgb1 significantly activated microglial cells (Iba-1 expression) and selectively induced Pde4b expression with a minimal to no change in Pde4a and d isoforms. In comparison, the alcohol-induced decrease in brain cAMP levels was completely inhibited in WT mice treated with the Pde4 specific pharmacologic inhibitor rolipram and in Pde4b-/- mice. Moreover, all the observed markers of alcohol-induced brain inflammation were markedly attenuated. Importantly, glial cell activation induced by systemic endotoxemia (LPS administration) was also markedly decreased in Pde4b-/- mice. Taken together, these findings strongly support the notion that Pde4b plays a critical role in coordinating alcohol-induced, peripheral endotoxemia mediated neuro-inflammation and could serve as a significant therapeutic target.


Assuntos
Transtornos Relacionados ao Uso de Álcool/enzimologia , Transtornos Relacionados ao Uso de Álcool/imunologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Inflamação/enzimologia , Transtornos Relacionados ao Uso de Álcool/patologia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/enzimologia , Astrócitos/imunologia , Astrócitos/patologia , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Encéfalo/imunologia , Encéfalo/patologia , Células Cultivadas , Depressores do Sistema Nervoso Central/administração & dosagem , AMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Etanol/administração & dosagem , Expressão Gênica/efeitos dos fármacos , Inflamação/induzido quimicamente , Inflamação/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/efeitos dos fármacos , Microglia/enzimologia , Microglia/imunologia , Microglia/patologia , Inibidores da Fosfodiesterase 4/farmacologia , RNA Mensageiro/metabolismo , Rolipram/farmacologia
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