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1.
Artigo em Inglês | MEDLINE | ID: mdl-39301965

RESUMO

BACKGROUND: We have developed a mouse model of Parenteral Nutrition Associated Liver Disease in which PN infusion results in cholestatic liver injury. In the liver, the master circadian genes Arntl/Bmal drive rhythmic gene expression and regulate circadian expression of hepatic functions including bile acid synthesis. The aim of this study was to examine the effect of continuous PN on ileal and hepatic expression of circadian regulatory (CR) genes, FXR signaling and bile acid synthesis in mice. METHODS: WT mice were exposed to continuous soy oil lipid emulsion-based PN infusion through a central venous catheter for 4 days (PN). Water was provided ad libitum, but no nutrients were provided enterally. On d4, mice were sacrificed every 6 hours (7AM, 1PM, 7PM and 1AM), and ileal, hepatic tissue and serum harvested. From tissue samples, the relative expression of circadian transcription factors and FXR signaling was assessed. RESULTS: Administration of 4d PN increased hepatic injury, inflammatory cytokine expression and gut permeability. In the ileum, PN activated FXR and induced expression of Fgf15 and Nr0b2. In the liver, expression of FXR-downstream targets was dysregulated. PN administrations impacted hepatic and ileal circadian transcription factor mRNA expression which was discordant between the two organs. CONCLUSIONS: Dysregulation of circadian regulatory machinery is in part due to discordance of the gut-liver axis during PN. Pharmacologic targeting of CR as a therapeutic strategy for PNALD thus deserves further investigation.

2.
Hepatology ; 79(5): 986-1004, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37976384

RESUMO

BACKGROUND AND AIMS: Parenteral nutrition-associated cholestasis (PNAC) is an important complication in patients with intestinal failure with reduced LRH-1 expression. Here, we hypothesized that LRH-1 activation by its agonist, dilauroylphosphatidylcholine (DLPC), would trigger signal transducer and activator of transcription 6 (STAT6) signaling and hepatic macrophage polarization that would mediate hepatic protection in PNAC. APPROACH AND RESULTS: PNAC mouse model (oral DSSx4d followed by PNx14d; DSS-PN) was treated with LRH-1 agonist DLPC (30 mg/kg/day) intravenously. DLPC treatment prevented liver injury and cholestasis while inducing hepatic mRNA expression of Nr5a2 (nuclear receptor subfamily 5 group A member 2), Abcb11 (ATP binding cassette subfamily B member 11), Abcg5 (ATP-binding cassette [ABC] transporters subfamily G member 5), Abcg8 (ATP-binding cassette [ABC] transporters subfamily G member 8), nuclear receptor subfamily 0, and ATP-binding cassette subfamily C member 2 ( Abcc2) mRNA, all of which were reduced in PNAC mice. To determine the mechanism of the DLPC effect, we performed RNA-sequencing analysis of the liver from Chow, DSS-PN, and DSS-PN/DLPC mice, which revealed DLPC upregulation of the anti-inflammatory STAT6 pathway. In intrahepatic mononuclear cells or bone-marrow derived macrophages (BMDM) from PNAC mice, DLPC treatment prevented upregulation of pro-inflammatory (M1) genes, suppressed activation of NFκB and induced phosphorylation of STAT6 and its target genes, indicating M2 macrophage polarization. In vitro, incubation of DLPC with cultured macrophages showed that the increased Il-1b and Tnf induced by exposure to lipopolysaccharides or phytosterols was reduced significantly, which was associated with increased STAT6 binding to promoters of its target genes. Suppression of STAT6 expression by siRNA in THP-1 cells exposed to lipopolysaccharides, phytosterols, or both resulted in enhanced elevation of IL-1B mRNA expression. Furthermore, the protective effect of DLPC in THP-1 cells was abrogated by STAT6 siRNA. CONCLUSIONS: These results indicate that activation of LRH-1 by DLPC may protect from PNAC liver injury through STAT6-mediated macrophage polarization.


Assuntos
Colestase , Fosfatidilcolinas , Fitosteróis , Humanos , Camundongos , Animais , Lipoproteínas/metabolismo , Fator de Transcrição STAT6/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Colestase/etiologia , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Células de Kupffer/metabolismo , RNA Interferente Pequeno , RNA Mensageiro/metabolismo , Nutrição Parenteral/efeitos adversos , Trifosfato de Adenosina
3.
PLoS One ; 18(8): e0290385, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37647292

RESUMO

BACKGROUND: We have developed a mouse model of Parenteral Nutrition Associated Cholestasis (PNAC) in which combining intestinal inflammation and PN infusion results in cholestasis, hepatic macrophage activation, and transcriptional suppression of bile acid and sterol signaling and transport. In the liver, the master circadian gene regulators Bmal/Arntl and Clock drive circadian modulation of hepatic functions, including bile acid synthesis. Once activated, Bmal and Clock are downregulated by several transcription factors including Reverbα (Nr1d1), Dbp (Dbp), Dec1/2 (Bhlhe40/41), Cry1/2 (Cry1/2) and Per1/2 (Per1/2). The aim of this study was to examine the effects of PN on expression of hepatic circadian rhythm (CR) regulatory genes in mice. METHODS: WT, IL1KO or TNFRKO mice were exposed to dextran sulfate sodium (DSS) for 4 days followed by soy-oil lipid emulsion-based PN infusion through a central venous catheter for 14 days (DSS-PN) and the expression of key CR regulatory transcription factors evaluated. Animals were NPO on a 14 hr light-dark cycle and were administered PN continuously over 24 hrs. Mice were sacrificed, and hepatic tissue obtained at 9-10AM (Zeitgeber Z+3/Z+4 hrs). PNAC was defined by increased serum aspartate aminotransferase, alanine aminotransferase, total bile acids, and total bilirubin and the effect of i.p. injection of recombinant IL-1ß (200ng/mouse) or TNFα (200ng/mouse) on CR expression was examined after 4 hrs. RESULTS: In the PNAC model, DSS-PN increased serum biomarkers of hepatic injury (ALT, AST, serum bile acids) which was suppressed in both DSS-PN IL1KO and DSS-PN TNFRKO mice. In WT DSS-PN, mRNA expression of Arntl and Dec1 was suppressed corresponding to increased Nr1d1, Per2, Dbp and Dec2. These effects were ameliorated in both DSS-PN IL1KO and DSS-PN TNFRKO groups. Western analysis of the circadian transcription factor network revealed in WT mice DSS-PN significantly suppressed Reverbα, Bmal, Dbp, Per2 and Mtnr1b. With the exception of Dbp, DSS-PN mediated suppression was ameliorated by both IL1KO and TNFRKO. Intraperitoneal injection of IL-1ß or TNFα into WT mice increased serum AST and ALT and suppressed mRNA expression of Nr1d1, Arntl and Clock and increased Dbp and Per2. CONCLUSIONS: Altered expression of CR-dependent regulatory genes during PNAC accompanies cholestasis and is, in part, due to increased cytokine (IL-1ß and TNFα) production. Evaluation of the effects of modulating CR in PNAC thus deserves further investigation.


Assuntos
Traumatismos Abdominais , Colestase , Animais , Camundongos , Fator de Necrose Tumoral alfa , Fatores de Transcrição ARNTL , Genes Reguladores , Colestase/genética , Nutrição Parenteral , Ácidos e Sais Biliares , RNA Mensageiro
5.
Sci Rep ; 13(1): 7752, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-37173326

RESUMO

Prolonged parenteral nutrition (PN) can lead to PN associated cholestasis (PNAC). Intestinally derived lipopolysaccharides and infused PN phytosterols lead to activation of NFκB, a key factor in PNAC. Our objective was to determine if inhibition of HNF4α could interfere with NFκB to alleviate murine PNAC. We showed that HNF4α antagonist BI6015 (20 mg/kg/day) in DSS-PN (oral DSS x4d followed by Total PN x14d) mice prevented the increased AST, ALT, bilirubin and bile acids and reversed mRNA suppression of hepatocyte Abcg5/8, Abcb11, FXR, SHP and MRP2 that were present during PNAC. Further, NFκB phosphorylation in hepatocytes and its binding to LRH-1 and BSEP promoters in liver, which are upregulated in DSS-PN mice, were inhibited by BI6015 treatment. BI6015 also prevented the upregulation in liver macrophages of Adgre1 (F4/80) and Itgam (CD11B) that occurs in DSS-PN mice, with concomitant induction of anti-inflammatory genes (Klf2, Klf4, Clec7a1, Retnla). In conclusion, HNF4α antagonism attenuates PNAC by suppressing NFκB activation and signaling while inducing hepatocyte FXR and LRH-1 and their downstream bile and sterol transporters. These data identify HNF4α antagonism as a potential therapeutic target for prevention and treatment of PNAC.


Assuntos
Colestase , Camundongos , Animais , Colestase/metabolismo , Fígado/metabolismo , Benzimidazóis/metabolismo , Nutrição Parenteral , NF-kappa B/metabolismo
6.
Hepatol Commun ; 7(3): e0056, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36848082

RESUMO

BACKGROUND AND AIMS: Parenteral nutrition (PN) in patients with intestinal failure can lead to cholestasis (PNAC). In a PNAC mouse model, farnesoid X receptor (FXR) agonist (GW4064) treatment alleviated IL-1ß-dependent cholestatic liver injury. The objective of this study was to determine whether this hepatic protection of FXR activation is mediated through IL-6-STAT3 signaling. APPROACH AND RESULTS: Hepatic apoptotic pathways [Fas-associated protein with death domain (Fas) mRNA, caspase 8 protein, and cleaved caspase 3] and IL-6-STAT3 signaling, and expression of its downstream effectors Socs1/3 were all upregulated in the mouse PNAC model (dextran sulfate sodium enterally × 4 d followed by total PN for 14 d). Il1r-/- mice were protected from PNAC in conjunction with suppression of the FAS pathway. GW4064 treatment in the PNAC mouse increased hepatic FXR binding to the Stat3 promoter, further increased STAT3 phosphorylation and upregulated Socs1 and Socs3 mRNA, and prevented cholestasis. In HepG2 cells and primary mouse hepatocytes, IL-1ß induced IL-6 mRNA and protein, which were suppressed by GW4064. In IL-1ß or phytosterols treated HepG2 and Huh7 cells, siRNA knockdown of STAT3 significantly reduced GW4064-upregulated transcription of hepatoprotective nuclear receptor subfamily 0, group B, member 2 (NR0B2) and ABCG8. CONCLUSIONS: STAT3 signaling mediated in part the protective effects of GW4064 in the PNAC mouse, and in HepG2 cells and hepatocytes exposed to either IL-1ß or phytosterols, 2 factors critical in PNAC pathogenesis. These data demonstrate that FXR agonists may mediate hepatoprotective effects in cholestasis by inducing STAT3 signaling.


Assuntos
Colestase , Interleucina-6 , Animais , Camundongos , Interleucina-6/genética , Transdução de Sinais , RNA Interferente Pequeno , Hepatócitos , Modelos Animais de Doenças
7.
Hepatol Commun ; 7(1): e0020, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36633484

RESUMO

BACKGROUND AND AIMS: Cholestatic liver diseases, including primary sclerosing cholangitis, are characterized by periportal inflammation with progression to hepatic fibrosis and ultimately cirrhosis. We recently reported that the thioredoxin antioxidant response is dysregulated during primary sclerosing cholangitis. The objective of this study was to examine the impact of genetic and pharmacological targeting of thioredoxin reductase 1 (TrxR1) on hepatic inflammation and liver injury during acute cholestatic injury. APPROACH AND RESULTS: Primary mouse hepatocytes and intrahepatic macrophages were isolated from 3-day bile duct ligated (BDL) mice and controls. Using wildtype and mice with a liver-specific deletion of TrxR1 (TrxR1LKO), we analyzed the effect of inhibition or ablation of TrxR1 signaling on liver injury and inflammation. Immunohistochemical analysis of livers from BDL mice and human cholestatic patients revealed increased TrxR1 staining in periportal macrophages and hepatocytes surrounding fibrosis. qPCR analysis of primary hepatocytes and intrahepatic macrophages revealed increased TrxR1 mRNA expression following BDL. Compared with sham controls, BDL mice exhibited increased inflammation, necrosis, and increased mRNA expression of pro-inflammatory cytokines, fibrogenesis, the NLRP3 inflammatory complex, and increased activation of NFkB, all of which were ameliorated in TrxR1LKO mice. Importantly, following BDL, TrxR1LKO induced periportal hepatocyte expression of Nrf2-dependent antioxidant proteins and increased mRNA expression of basolateral bile acid transporters with reduced expression of bile acid synthesis genes. In the acute BDL model, the TrxR1 inhibitor auranofin (10 mg/kg/1 d preincubation, 3 d BDL) ameliorated BDL-dependent increases in Nlrp3, GsdmD, Il1ß, and TNFα mRNA expression despite increasing serum alanine aminotransferase, aspartate aminotransferase, bile acids, and bilirubin. CONCLUSIONS: These data implicate TrxR1-signaling as an important regulator of inflammation and bile acid homeostasis in cholestatic liver injury.


Assuntos
Colangite Esclerosante , Colestase , Animais , Humanos , Camundongos , Antioxidantes , Ácidos e Sais Biliares , Inflamação , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Ativação de Macrófagos , Proteína 3 que Contém Domínio de Pirina da Família NLR , RNA Mensageiro , Tiorredoxina Redutase 1/genética
8.
JPEN J Parenter Enteral Nutr ; 46(5): 1096-1106, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34664730

RESUMO

BACKGROUND: We have recently reported a mouse model of PN-associated cholestasis (PNAC) in which combining intestinal inflammation and PN infusion results in cholestasis, hepatic macrophage activation, and transcriptional suppression of canalicular bile acid, bilirubin and sterol transporters Abcb11, Abcc2 and Abcg5/8. The aim of this study was to examine the role of TNFα in promoting PNAC in mice. METHODS: First, recombinant TNFα was administered to mice as well as in hepatocyte cell culture. Second, Tnfr1/2KO or wild-type (WT) mice were exposed to dextran sulfate sodium (DSS) for 4 days followed by soy-oil lipid emulsion-based PN infusion through a central venous catheter for 14 days (DSS-PN). Finally, WT/DSS-PN mice were also infused with infliximab at 10 mg/kg on days 3 and 10 of PN. PNAC was defined by increased serum aspartate aminotransferase, alanine aminotransferase, total bile acids, and bilirubin. RESULTS: Intraperitoneal injection of TNFα into WT mice or TNFα treatment of Huh7 hepatocarcinoma cells and primary mouse hepatocytes suppressed messenger RNA (mRNA) transcription of bile (Abcb11, Abcc2]) and sterol transporters (Abcg5/8) and their regulators Nr1h3 and Nr1h4. DSS-PN mice with PNAC had increased hepatic TNFα mRNA expression and significant reduction of mRNA expression of Abcb11, Abcc2, Abcg5/8, Nr1h3, and Nr1h4. In contrast, PNAC development was prevented and mRNA expression normalized in both Tnfr1/2KO /DSS-PN mice and DSS-PN mice treated with infliximab. CONCLUSIONS: TNFα is a key mediator in the pathogenesis of PNAC through suppression of hepatocyte Abcb11, Abcc2, and Abcg5/8. Pharmacologic targeting of TNFα as a therapeutic strategy for PNAC thus deserves further investigation.


Assuntos
Colestase , Fator de Necrose Tumoral alfa , Animais , Ácidos e Sais Biliares , Bilirrubina , Colestase/etiologia , Infliximab , Camundongos , Nutrição Parenteral , RNA Mensageiro , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Esteróis
10.
Hepatology ; 75(2): 252-265, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34387888

RESUMO

BACKGROUND AND AIMS: Parenteral nutrition (PN)-associated cholestasis (PNAC) complicates the care of patients with intestinal failure. In PNAC, phytosterol containing PN synergizes with intestinal injury and IL-1ß derived from activated hepatic macrophages to suppress hepatocyte farnesoid X receptor (FXR) signaling and promote PNAC. We hypothesized that pharmacological activation of FXR would prevent PNAC in a mouse model. APPROACH AND RESULTS: To induce PNAC, male C57BL/6 mice were subjected to intestinal injury (2% dextran sulfate sodium [DSS] for 4 days) followed by central venous catheterization and 14-day infusion of PN with or without the FXR agonist GW4064. Following sacrifice, hepatocellular injury, inflammation, and biliary and sterol transporter expression were determined. GW4064 (30 mg/kg/day) added to PN on days 4-14 prevented hepatic injury and cholestasis; reversed the suppressed mRNA expression of nuclear receptor subfamily 1, group H, member 4 (Nr1h4)/FXR, ATP-binding cassette subfamily B member 11 (Abcb11)/bile salt export pump, ATP-binding cassette subfamily C member 2 (Abcc2), ATP binding cassette subfamily B member 4(Abcb4), and ATP-binding cassette subfamily G members 5/8(Abcg5/8); and normalized serum bile acids. Chromatin immunoprecipitation of liver showed that GW4064 increased FXR binding to the Abcb11 promoter. Furthermore, GW4064 prevented DSS-PN-induced hepatic macrophage accumulation, hepatic expression of genes associated with macrophage recruitment and activation (ll-1b, C-C motif chemokine receptor 2, integrin subunit alpha M, lymphocyte antigen 6 complex locus C), and hepatic macrophage cytokine transcription in response to lipopolysaccharide in vitro. In primary mouse hepatocytes, GW4064 activated transcription of FXR canonical targets, irrespective of IL-1ß exposure. Intestinal inflammation and ileal mRNAs (Nr1h4, Fgf15, and organic solute transporter alpha) were not different among groups, supporting a liver-specific effect of GW4064 in this model. CONCLUSIONS: GW4064 prevents PNAC in mice through restoration of hepatic FXR signaling, resulting in increased expression of canalicular bile and of sterol and phospholipid transporters and suppression of macrophage recruitment and activation. These data support augmenting FXR activity as a therapeutic strategy to alleviate or prevent PNAC.


Assuntos
Colestase/prevenção & controle , Expressão Gênica/efeitos dos fármacos , Isoxazóis/farmacologia , Nutrição Parenteral/efeitos adversos , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/genética , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/metabolismo , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Animais , Ácidos e Sais Biliares/sangue , Colestase/etiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/metabolismo , Interleucina-1beta/farmacologia , Enteropatias/induzido quimicamente , Enteropatias/terapia , Isoxazóis/uso terapêutico , Lipoproteínas/genética , Hepatopatias/etiologia , Hepatopatias/patologia , Hepatopatias/prevenção & controle , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína 2 Associada à Farmacorresistência Múltipla/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
J Biol Chem ; 297(6): 101400, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34774795

RESUMO

ATP-binding cassette, subfamily B member 11 (ABCB11) is an efflux transporter for bile acids on the liver canalicular membrane. The expression of this transporter is reduced in cholestasis; however, the mechanisms contributing to this reduction are unclear. In this study, we sought to determine whether miR-199a-5p contributes to the depletion of ABCB11/Abcb11 in cholestasis in mice. In a microRNA (miRNA) screen of mouse liver after common bile duct ligation (CBDL), we found that miR-199a-5p was significantly upregulated by approximately fourfold. In silico analysis predicted that miR-199a-5p would target the 3'-untranslated region (3'-UTR) of ABCB11/Abcb11 mRNA. The expression of ABCB11-3'-UTR luciferase construct in Huh-7 cells was markedly inhibited by cotransfection of a miRNA-199a-5p mimic, which was reversed by an miRNA-199a-5p mimic inhibitor. We also show treatment of mice after CBDL with the potent nuclear receptor FXR agonist obeticholic acid (OCA) significantly increased Abcb11 mRNA and protein and decreased miR-199a-5p expression. Computational mapping revealed a well-conserved FXR-binding site (FXRE) in the promoter of the gene encoding miR-199a-5, termed miR199a-2. Electromobility shift, chromatin immunoprecipitation, and miR199a-2 promoter-luciferase assays confirmed that this binding site was functional. Finally, CBDL in mice led to depletion of nuclear repressor NcoR1 binding at the miR199a-2 promoter, which facilitates transcription of miR199a-2. In CBDL mice treated with OCA, NcoR1 recruitment to the miR199a-2 FXRE was maintained at levels found in sham-operated mice. In conclusion, we demonstrate that miR-199a-5p is involved in regulating ABCB11/Abcb11 expression, is aberrantly upregulated in obstructive cholestasis, and is downregulated by the FXR agonist OCA.


Assuntos
Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/biossíntese , Colestase/metabolismo , Regulação da Expressão Gênica , MicroRNAs/metabolismo , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética , Animais , Ácido Quenodesoxicólico/análogos & derivados , Ácido Quenodesoxicólico/farmacologia , Colestase/tratamento farmacológico , Colestase/genética , Colestase/patologia , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Knockout , MicroRNAs/genética , Correpressor 1 de Receptor Nuclear/genética , Correpressor 1 de Receptor Nuclear/metabolismo
12.
Hepatology ; 74(6): 3284-3300, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34310734

RESUMO

BACKGROUND AND AIMS: Chronically administered parenteral nutrition (PN) in patients with intestinal failure carries the risk for developing PN-associated cholestasis (PNAC). We have demonstrated that farnesoid X receptor (FXR) and liver X receptor (LXR), proinflammatory interleukin-1 beta (IL-1ß), and infused phytosterols are important in murine PNAC pathogenesis. In this study we examined the role of nuclear receptor liver receptor homolog 1 (LRH-1) and phytosterols in PNAC. APPROACH AND RESULTS: In a C57BL/6 PNAC mouse model (dextran sulfate sodium [DSS] pretreatment followed by 14 days of PN; DSS-PN), hepatic nuclear receptor subfamily 5, group A, member 2/LRH-1 mRNA, LRH-1 protein expression, and binding of LRH-1 at the Abcg5/8 and Cyp7a1 promoter was reduced. Interleukin-1 receptor-deficient mice (Il-1r-/- /DSS-PN) were protected from PNAC and had significantly increased hepatic mRNA and protein expression of LRH-1. NF-κB activation and binding to the LRH-1 promoter were increased in DSS-PN PNAC mice and normalized in Il-1r-/- /DSS-PN mice. Knockdown of NF-κB in IL-1ß-exposed HepG2 cells increased expression of LRH-1 and ABCG5. Treatment of HepG2 cells and primary mouse hepatocytes with an LRH-1 inverse agonist, ML179, significantly reduced mRNA expression of FXR targets ATP binding cassette subfamily C member 2/multidrug resistance associated protein 2 (ABCC2/MRP2), nuclear receptor subfamily 0, groupB, member 2/small heterodimer partner (NR0B2/SHP), and ATP binding cassette subfamily B member 11/bile salt export pump (ABCB11/BSEP). Co-incubation with phytosterols further reduced expression of these genes. Similar results were obtained by suppressing the LRH-1 targets ABCG5/8 by treatment with small interfering RNA, IL-1ß, or LXR antagonist GSK2033. Liquid chromatography-mass spectrometry and chromatin immunoprecipitation experiments in HepG2 cells showed that ATP binding cassette subfamily G member 5/8 (ABCG5/8) suppression by GSK2033 increased the accumulation of phytosterols and reduced binding of FXR to the SHP promoter. Finally, treatment with LRH-1 agonist, dilauroyl phosphatidylcholine (DLPC) protected DSS-PN mice from PNAC. CONCLUSIONS: This study suggests that NF-κB regulation of LRH-1 and downstream genes may affect phytosterol-mediated antagonism of FXR signaling in the pathogenesis of PNAC. LRH-1 could be a potential therapeutic target for PNAC.


Assuntos
Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Colestase/etiologia , Lipoproteínas/metabolismo , NF-kappa B/metabolismo , Nutrição Parenteral/efeitos adversos , Fitosteróis/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Colestase/metabolismo , Imunoprecipitação da Cromatina , Modelos Animais de Doenças , Cromatografia Gasosa-Espectrometria de Massas , Técnicas de Silenciamento de Genes , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos C57BL
14.
Seizure ; 78: 31-37, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32155575

RESUMO

Over the last few decades the ILAE classifications for seizures and epilepsies (ILAE-EC) have been updated repeatedly to reflect the substantial progress that has been made in diagnosis and understanding of the etiology of epilepsies and seizures and to correct some of the shortcomings of the terminology used by the original taxonomy from the 1980s. However, these proposals have not been universally accepted or used in routine clinical practice. During the same period, a separate classification known as the "Four-dimensional epilepsy classification" (4D-EC) was developed which includes a seizure classification based exclusively on ictal symptomatology, which has been tested and adapted over the years. The extensive arguments for and against these two classification systems made in the past have mainly focused on the shortcomings of each system, presuming that they are incompatible. As a further more detailed discussion of the differences seemed relatively unproductive, we here review and assess the concordance between these two approaches that has evolved over time, to consider whether a classification incorporating the best aspects of the two approaches is feasible. To facilitate further discussion in this direction we outline a concrete proposal showing how such a compromise could be accomplished, the "Integrated Epilepsy Classification". This consists of five categories derived to different degrees from both of the classification systems: 1) a "Headline" summarizing localization and etiology for the less specialized users, 2) "Seizure type(s)", 3) "Epilepsy type" (focal, generalized or unknown allowing to add the epilepsy syndrome if available), 4) "Etiology", and 5) "Comorbidities & patient preferences".


Assuntos
Epilepsia/classificação , Guias de Prática Clínica como Assunto , Sociedades Médicas , Humanos
16.
Hepatol Commun ; 3(12): 1674-1686, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31832574

RESUMO

Adenosine triphosphate-binding cassette subfamily C member 2 (ABCC2/Abcc2) is critically important to biliary excretion of many endobiotic and xenobiotic compounds, and is a major driving force for bile acid-independent bile flow. Abcc2 expression is reduced at the messenger RNA (mRNA) and protein levels in various forms of experimental cholestasis. In a microRNA (miRNA) screen of mouse liver after biliary obstruction, we found that miRNA let7a-5p was significantly up-regulated approximately 4-fold. Similarly, ABCC2 mRNA was depleted and miRNA let7a-5p was elevated over 4-fold in livers of children with biliary atresia compared with normal livers. In silico analysis predicted that let7a-5p would target the 3' untranslated region (3' UTR) of ABCC2/Abcc2 RNA. The objective of this study was to determine whether let7a-5p contributes to the depletion of ABCC2/Abcc2 in cholestasis. To demonstrate the functional importance of miRNA let7a-5p in regulating the expression of ABCC2, co-transfection of a let7a-5p mimic and an ABCC2-3' UTR luciferase construct into Huh-7 cells led to a marked inhibition of luciferase activity by about 60%-70% compared with controls, which was reversed by a let7a-5p mimic inhibitor. Expression of this mimic led to a significant decrease in endogenous ABCC2 mRNA and protein levels in a Huh-7 liver cell line, which could be blocked by expression of a let7a-5p mimic inhibitor. Injection of a lentivirus let7a-5p inhibitor into normal mouse liver or into mouse liver after common bile duct ligation led to a significant increase in endogenous Abcc2 mRNA and protein levels and a depletion of let7a-5p mRNA levels compared with untreated, saline-injected livers or livers treated with an inactive lentivirus control. Conclusion: These studies demonstrate that miR-let7a-5p is involved in regulating ABCC2/Abcc2 expression, and is aberrantly up-regulated in obstructive cholestasis.

17.
Epilepsia ; 60(6): 1032-1039, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30924146

RESUMO

This article critiques the International League Against Epilepsy (ILAE) 2015-2017 classifications of epilepsy, epileptic seizures, and status epilepticus. It points out the following shortcomings of the ILAE classifications: (1) they mix semiological terms with epileptogenic zone terminology; (2) simple and widely accepted terminology has been replaced by complex terminology containing less information; (3) seizure evolution cannot be described in any detail; (4) in the four-level epilepsy classification, level two (epilepsy category) overlaps almost 100% with diagnostic level one (seizure type); and (5) the design of different classifications with distinct frameworks for newborns, adults, and patients in status epilepticus is confusing. The authors stress the importance of validating the new ILAE classifications and feel that the decision of Epilepsia to accept only manuscripts that use the ILAE classifications is premature and regrettable.


Assuntos
Epilepsia/classificação , Convulsões/classificação , Humanos , Estado Epiléptico/classificação
18.
Epileptic Disord ; 21(1): 1-29, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30782582

RESUMO

This educational review describes the classification of paroxysmal events and a four-dimensional epilepsy classification system. Paroxysmal events are classified as epileptic and non-epileptic paroxysmal events. Non-epileptic events are, in turn, classified as psychogenic and organic paroxysmal events. The following four dimensions are used to classify epileptic paroxysmal events: ictal semiology, the epileptogenic zone, etiology, and comorbidities. Efforts are made to keep these four dimensions as independent as possible. The review also includes 12 educational vignettes and three more detailed case reports classified using the 2017 classification of the ILAE and the four-dimensional epilepsy classification. In addition, a case is described which is classified using the four-dimensional epilepsy classification with different degrees of precision by an emergency department physician, a neurologist, and an epileptologist. [Published with video sequences on www.epilepticdisorders.com].


Assuntos
Epilepsia/classificação , Epilepsia/etiologia , Epilepsia/fisiopatologia , Humanos
19.
Nat Commun ; 9(1): 1393, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29643332

RESUMO

In infants intolerant of enteral feeding because of intestinal disease, parenteral nutrition may be associated with cholestasis, which can progress to end-stage liver disease. Here we show the function of hepatic macrophages and phytosterols in parenteral nutrition-associated cholestasis (PNAC) pathogenesis using a mouse model that recapitulates the human pathophysiology and combines intestinal injury with parenteral nutrition. We combine genetic, molecular, and pharmacological approaches to identify an essential function of hepatic macrophages and IL-1ß in PNAC. Pharmacological antagonism of  IL-1 signaling or genetic deficiency in CCR2, caspase-1 and caspase-11, or IL-1 receptor (which binds both IL-1α and IL-1ß) prevents PNAC in mice. IL-1ß increases hepatocyte NF-κB signaling, which interferes with farnesoid X receptor and liver X receptor bonding to respective promoters of canalicular bile and sterol transporter genes (Abcc2, Abcb11, and Abcg5/8), resulting in transcriptional suppression and subsequent cholestasis. Thus, hepatic macrophages, IL-1ß, or NF-κB may be targets for restoring bile and sterol transport to treat PNAC.


Assuntos
Colestase/genética , Interleucina-1beta/genética , Fígado/imunologia , Macrófagos/imunologia , NF-kappa B/genética , Receptores CCR2/genética , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/imunologia , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/imunologia , Animais , Caspase 1/genética , Caspase 1/imunologia , Caspases/genética , Caspases/imunologia , Caspases Iniciadoras , Colestase/etiologia , Colestase/imunologia , Colestase/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hepatócitos/imunologia , Hepatócitos/patologia , Humanos , Recém-Nascido , Interleucina-1beta/imunologia , Lipoproteínas/genética , Lipoproteínas/imunologia , Fígado/patologia , Receptores X do Fígado/genética , Receptores X do Fígado/imunologia , Macrófagos/patologia , Masculino , Camundongos , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/imunologia , NF-kappa B/imunologia , Nutrição Parenteral/efeitos adversos , Receptores CCR2/deficiência , Receptores CCR2/imunologia , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/imunologia , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/imunologia , Transdução de Sinais
20.
BMC Neurol ; 16(1): 227, 2016 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-27855635

RESUMO

BACKGROUND: The burden of neurological diseases is increasing in developing countries. However, there is a prominent scarcity of literature on the incidence of neurological diseases in sub-Saharan Africa. This study was therefore undertaken to determine the prevalence and incidence of neurological diseases in this setting to serve as a baseline for planning and care for neurological disorders in Uganda. METHODS: The study was conducted within rural and urban Mukono district, east of Kampala city of Uganda, central region. Over a period of six months, a cross sectional survey was conducted and screening was performed using a standardized questionnaire. All subjects with neurological symptoms and signs were reviewed by a team of neurologists and neurological diagnoses made. RESULTS: Of the 3000 study subjects, 50.3% (1510/3000) were from the rural setting. Out of the participants screened, 67.4% were female, with a median age of 33 years. Among the 98 subjects with confirmed neurological disorders, the frequency of diseases was as follows; peripheral neuropathy (46.2%), chronic headaches (26.4%), and epilepsy (8.5%), followed by pain syndromes (7.5%), stroke (6.6%) and tremors/Parkinson disease (3.8%). The crude prevalence rates of these disorders (95% CI) were 14.3% (8.5-24.1); 13.3% (7.7-22.8); 33.7% (23.9-47.4) for stroke, epilepsy and peripheral neuropathy respectively. Peripheral neuropathy followed by chronic headaches had the highest estimated incidence/1000 years. Stroke had an estimated incidence of 3.6 new cases with 95% CI of (2.1-6.1)/1000 years. CONCLUSION: Peripheral neuropathy, chronic headaches and epilepsy disorders are major causes of morbidity in Sub-Saharan settings. There is an urgent need of more robust and powered studies to determine the incidence of these diseases.


Assuntos
Doenças do Sistema Nervoso/epidemiologia , Adolescente , Adulto , Idoso , Estudos Transversais , Países em Desenvolvimento , Epilepsia/epidemiologia , Epilepsia/etiologia , Feminino , Transtornos da Cefaleia/epidemiologia , Transtornos da Cefaleia/etiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia , Prevalência , População Rural , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Inquéritos e Questionários , Uganda/epidemiologia , Saúde da População Urbana , Adulto Jovem
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