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1.
Medicine (Baltimore) ; 99(36): e21463, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32898995

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a common chronic condition caused by the accumulation of fat in the liver. NAFLD may range from simple steatosis to advanced cirrhosis, and affects more than 1 billion people around the world. To date, there has been no effective treatment for NAFLD. In this study, we evaluated the expression of 4 candidate NAFLD biomarkers to assess their possible applicability in the classification and treatment of the disease.Twenty-six obese subjects, who underwent bariatric surgery, were recruited and their liver biopsies obtained. Expression of 4 candidate biomarker genes, PNPLA3, COL1A1, PPP1R3B, and KLF6 were evaluated at gene and protein levels by RT-qPCR and enzyme-linked immunosorbent assay (ELISA), respectively.A significant increase in the levels of COL1A1 protein (P = .03) and PNPLA3 protein (P = .03) were observed in patients with fibrosis-stage NAFLD compared to that in patients with steatosis-stage NAFLD. However, no significant differences were found in abundance of PPP1R3B and KLF6 proteins or at the gene level for any of the candidate.This is the first study, to our knowledge, to report on the expression levels of candidate biomarker genes for NAFLD in the Saudi population. Although PNPLA3 and PPP1R3B had been previously suggested as biomarkers for steatosis and KLF6 as a possible marker for the fibrosis stage of NAFLD, our results did not support these findings. However, other studies that had linked PNPLA3 to fibrosis in advanced NAFLD supported our current finding of high PNPLA3 protein in patients with fibrosis. Additionally, our results support COL1A1 protein as a potential biomarker for the fibrosis stage of NAFLD, and indicate its use in the screening of patients with NAFLD. Further studies are required to validate the use of COL1A1 as a biomarker for advanced NAFLD in a larger cohort.


Assuntos
Biomarcadores/metabolismo , Colágenos Fibrilares , Lipase , Proteínas de Membrana , Hepatopatia Gordurosa não Alcoólica/genética , Adulto , Estudos de Casos e Controles , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/classificação , Obesidade , Reação em Cadeia da Polimerase em Tempo Real , Arábia Saudita , Adulto Jovem
2.
PLoS Genet ; 16(8): e1008955, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32776921

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a metabolic disorder characterized by excess lipid accumulation in the liver without significant consumption of alcohol. The transmembrane 6 superfamily member 2 (TM6SF2) E167K missense variant strongly associates with NAFLD in humans. The E167K mutation destabilizes TM6SF2, resulting in hepatic lipid accumulation and low serum lipid levels. However, the molecular mechanism by which TM6SF2 regulates lipid metabolism remains unclear. By using tandem affinity purification in combination with mass spectrometry, we found that apolipoprotein B (APOB), ER lipid raft protein (ERLIN) 1 and 2 were TM6SF2-interacting proteins. ERLINs and TM6SF2 mutually bound and stabilized each other. TM6SF2 bound and stabilized APOB via two luminal loops. ERLINs did not interact with APOB directly but still increased APOB stability through stabilizing TM6SF2. This APOB stabilization was hampered by the E167K mutation that reduced the protein expression of TM6SF2. In mice, knockout of Tm6sf2 and knockdown of Tm6sf2 or Erlins decreased hepatic APOB protein level, causing lipid accumulation in the liver and lowering lipid levels in the serum. We conclude that defective APOB stabilization, as a result of ERLINs or TM6SF2 deficiency or E167K mutation, is a key factor contributing to NAFLD.


Assuntos
Apolipoproteína B-100/genética , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Hepatopatia Gordurosa não Alcoólica/genética , Animais , Colesterol/genética , Colesterol/metabolismo , Predisposição Genética para Doença , Genótipo , Humanos , Imunoprecipitação , Metabolismo dos Lipídeos/genética , Lipídeos/sangue , Lipídeos/genética , Camundongos , Camundongos Knockout , Complexos Multiproteicos/genética , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Polimorfismo de Nucleotídeo Único/genética , Ligação Proteica/genética , Transfecção
3.
PLoS One ; 15(8): e0237430, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841307

RESUMO

BACKGROUND & AIMS: Given ongoing challenges in non-invasive non-alcoholic liver disease (NAFLD) diagnosis, we sought to validate an ALT-based NAFLD phenotype using measures readily available in electronic health records (EHRs) and population-based studies by leveraging the clinical and genetic data in the Million Veteran Program (MVP), a multi-ethnic mega-biobank of US Veterans. METHODS: MVP participants with alanine aminotransferases (ALT) >40 units/L for men and >30 units/L for women without other causes of liver disease were compared to controls with normal ALT. Genetic variants spanning eight NAFLD risk or ALT-associated loci (LYPLAL1, GCKR, HSD17B13, TRIB1, PPP1R3B, ERLIN1, TM6SF2, PNPLA3) were tested for NAFLD associations with sensitivity analyses adjusting for metabolic risk factors and alcohol consumption. A manual EHR review assessed performance characteristics of the NAFLD phenotype with imaging and biopsy data as gold standards. Genetic associations with advanced fibrosis were explored using FIB4, NAFLD Fibrosis Score and platelet counts. RESULTS: Among 322,259 MVP participants, 19% met non-invasive criteria for NAFLD. Trans-ethnic meta-analysis replicated associations with previously reported genetic variants in all but LYPLAL1 and GCKR loci (P<6x10-3), without attenuation when adjusted for metabolic risk factors and alcohol consumption. At the previously reported LYPLAL1 locus, the established genetic variant did not appear to be associated with NAFLD, however the regional association plot showed a significant association with NAFLD 279kb downstream. In the EHR validation, the ALT-based NAFLD phenotype yielded a positive predictive value 0.89 and 0.84 for liver biopsy and abdominal imaging, respectively (inter-rater reliability (Cohen's kappa = 0.98)). HSD17B13 and PNPLA3 loci were associated with advanced fibrosis. CONCLUSIONS: We validate a simple, non-invasive ALT-based NAFLD phenotype using EHR data by leveraging previously established NAFLD risk-associated genetic polymorphisms.


Assuntos
Alanina Transaminase/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , 17-Hidroxiesteroide Desidrogenases/genética , Abdome/diagnóstico por imagem , Proteínas Adaptadoras de Transdução de Sinal/genética , Idoso , Alanina Transaminase/genética , Registros Eletrônicos de Saúde , Feminino , Loci Gênicos , Predisposição Genética para Doença , Variação Genética , Humanos , Lipase/genética , Fígado/patologia , Lisofosfolipase/genética , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/etnologia , Hepatopatia Gordurosa não Alcoólica/genética , Fenótipo , Fatores de Risco , Veteranos
4.
Life Sci ; 257: 118090, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679144

RESUMO

AIMS: This study aimed to investigate oxymatrine via regulating miR-182 improved the hepatic lipid accumulation in non-alcoholic fatty liver disease (NAFLD) model. MATERIALS AND METHODS: Wistar rats were fed high-fat and high-fructose diet (HFDHFr group) for 4 weeks and HepG2 cells were treated with palmitic acid (PA group), and then were given oxymatrine intervention. The expression profiles of miRNAs were accessed by RNA sequencing (RNA-Seq). Hematoxylin-eosin (HE) staining and Oil Red O staining were used to observe the inflammation and lipid accumulation in liver. The levels of sterol regulatory element binding protein-1c (SREBP-1c), acetyl-CoA carboxylase (ACC), fatty-acid synthase (FAS) and carnitine palmitoyltransferase 1A (CPT-1A) were detected by RT-qPCR and Western blotting, respectively. Cell viability was detected by Cell Counting Kit-8 (CCK-8). KEY FINDINGS: miR-182 was down-regulated in the HFDHFr group and PA group. Oxymatrine reduced body weight, and improved glucose tolerance and insulin resistance in the HFDHFr + OMT group compared with HFDHFr group. In addition, oxymatrine reduced the ratio (liver weight/body weight), the content of triglycerides (TG), hepatic lipid accumulation and steatosis. The levels of SREBP-1c, ACC, and FAS were significantly decreased, while the CPT-1A level was obviously elevated after oxymatrine intervention (P < 0.05). In vivo, miR-182 knockdown increased the levels of SREBP-1c, ACC and FAS, while reduced the CPT-1A level. Additionally, oxymatrine attenuated the effects of miR-182 inhibitor on lipid accumulation. SIGNIFICANCE: We presented a possible mechanism that oxymatrine alleviated hepatic lipid metabolism via regulating miR-182 in NAFLD model.


Assuntos
Alcaloides/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Quinolizinas/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica , Técnicas de Silenciamento de Genes , Células Hep G2 , Humanos , Resistência à Insulina , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Ácido Palmítico/administração & dosagem , Ratos , Ratos Wistar
5.
J Cancer Res Clin Oncol ; 146(10): 2461-2477, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32685988

RESUMO

PURPOSE: The aim of this study was to investigate DNA methylation alterations in non-alcoholic steatohepatitis (NASH)-related hepatocellular carcinomas (HCCs). METHODS: Genome-wide DNA methylation analysis was performed using the Infinium Human Methylation 450 K BeadChip, and levels of mRNA expression were analyzed by quantitative reverse transcription-PCR. RESULTS: Compared to 36 samples of normal control liver tissue (C), DNA methylation alterations were observed on 19,281 probes in 22 samples of cancerous tissue (T) obtained from patients showing histological features compatible with NASH in their non-cancerous liver tissue (N). Among those probes, 1396 were located within CpG islands or their shores and shelves, designed around the transcription start sites of 726 genes. In representative genes, such as DCAF4L2, CKLF, TRIM4, PRC1, UBE2C and TUBA1B, both DNA hypomethylation and mRNA overexpression were observed in T samples relative to C samples, and the levels of DNA methylation and mRNA expression were inversely correlated with each other. DNA hypomethylation occurred even in N samples at the precancerous NASH stage, and this was inherited by or further strengthened in T samples. DNA hypomethylation of DCAF4L2, CKLF and UBE2C was observed in both NASH-related and viral hepatitis-related HCCs, whereas that of TRIM4, PRC1 and TUBA1B occurred in a NASH-related HCC-specific manner. DNA hypomethylation and/or mRNA overexpression of these genes was frequently associated with the necroinflammatory grade of NASH and was correlated with poorer tumor differentiation. CONCLUSION: DNA methylation alterations may occur under the necroinflammatory conditions characteristic of NASH and participate in NASH-related hepatocarcinogenesis through aberrant expression of tumor-related genes.


Assuntos
Carcinoma Hepatocelular/genética , Metilação de DNA , Neoplasias Hepáticas/genética , Hepatopatia Gordurosa não Alcoólica/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Regulação Neoplásica da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
Nat Commun ; 11(1): 3067, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546794

RESUMO

Lipid transport and ATP synthesis are critical for the progression of non-alcoholic fatty liver disease (NAFLD), but the underlying mechanisms are largely unknown. Here, we report that the RNA-binding protein HuR (ELAVL1) forms complexes with NAFLD-relevant transcripts. It associates with intron 24 of Apob pre-mRNA, with the 3'UTR of Uqcrb, and with the 5'UTR of Ndufb6 mRNA, thereby regulating the splicing of Apob mRNA and the translation of UQCRB and NDUFB6. Hepatocyte-specific HuR knockout reduces the expression of APOB, UQCRB, and NDUFB6 in mice, reducing liver lipid transport and ATP synthesis, and aggravating high-fat diet (HFD)-induced NAFLD. Adenovirus-mediated re-expression of HuR in hepatocytes rescues the effect of HuR knockout in HFD-induced NAFLD. Our findings highlight a critical role of HuR in regulating lipid transport and ATP synthesis.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Proteína Semelhante a ELAV 1/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Trifosfato de Adenosina/biossíntese , Animais , Apolipoproteína B-100/genética , Apolipoproteína B-100/metabolismo , Citocromos c/genética , Citocromos c/metabolismo , Proteína Semelhante a ELAV 1/genética , Homeostase , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Precursores de RNA
8.
Life Sci ; 256: 117997, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32585242

RESUMO

AIMS: Non-alcoholic fatty liver disease (NAFLD) characterized by excessive hepatic fat deposition is an increasing public health issue worldwide. Insulin resistance is a pivotal factor in NAFLD progression. Studies have found that IGFBP5 was related to insulin sensitivity. Nevertheless, the role of IGFBP5 in NAFLD remains unclear. MATERIALS AND METHODS: NAFLD models were established in vitro and in vivo by treating HepG2 cells with free fatty acids (FFA) and feeding mice with high-fat diet (HFD), respectively. IGFBP5 expression was then analyzed in these models. The effects and mechanism of IGFBP5 on lipid lipogenesis, fatty acid ß-oxidation, and insulin resistance were investigated following IGFBP5 overexpression. Additionally, AMPK inhibitor compound C was used to treat HepG2 cells to confirm whether IGFBP5 functioned via activating AMPK pathway. KEY FINDINGS: IGFBP5 expression was decreased in both NAFLD models. IGFBP5 overexpression reduced levels of lipogenesis-associated proteins (SREBP-1c, FAS and ACC1), elevated expression of fatty acid ß-oxidation-related genes (PPARα, CPT1A and ACOX1), decreased intracellular lipid droplets, promoted glucose uptake and glycogenesis, and activated IRS1/Akt and AMPK pathways. Administration of IGFBP5 vectors also decreased body weight and relieved liver damage in HFD-treated mice. In contrast, compound C abrogated the influences of IGFBP5 overexpression on cell models. SIGNIFICANCE: IGFBP5 dampened hepatic lipid accumulation and insulin resistance in NAFLD development via activating AMPK pathway. This study indicates that IGFBP5 may be a novel therapeutic agent for NAFLD.


Assuntos
Resistência à Insulina/genética , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Metabolismo dos Lipídeos/genética , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Proteínas de Transporte/genética , Dieta Hiperlipídica , Modelos Animais de Doenças , Ácidos Graxos não Esterificados/administração & dosagem , Regulação da Expressão Gênica , Células Hep G2 , Humanos , Lipogênese/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/genética
9.
Life Sci ; 253: 117678, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32376267

RESUMO

AIMS: The endoplasmic reticulum (ER) stress response plays a crucial role in the development of nonalcoholic steatohepatitis (NASH). Heme oxygenase-1 (HO-1) exerts beneficial effects against oxidative injury in NASH. This study is aimed to clarify whether HO-1 is an effective therapeutic strategy for NASH via regulation of ER stress. METHODS: The C57BL/6J mice were fed with methionine-choline deficient (MCD) for 4 weeks and high fat-high carbohydrate-high cholesterol (HFD) diet for 16 weeks, with hemin or zinc protoporphyrin IX (ZnPP-IX), respectively. The LO-2 cells were cultured in palmitic medium, with transfected pEX-HO-1 or sh-HO-1 plasmid for 24 h. Meanwhile, thirty NASH patients and 15 health controls were enrolled. The ER ultrastructure was observed by transmission electron microscopy (TEM) and confocal microscopy. The expressions of mRNAs and proteins of HO-1, ER stress related genes were detected by real time PCR, western blot and immunohistochemical staining, respectively. RESULTS: The swelled and broken rough endoplasmic reticulums were observed in MCD and HFD fed mice. The reactive hepatic expression of HO-1 was related with the increased ROS production and ER stress, companied with upregulation of GRP78, p-IRE1, PERK, ATF6. Through hemin administration, hepatocyte apoptosis was suppressed companied down-regulation of CHOP, caspase12 and up-regulation of BCL2. Conserved results were exhibited in ZnPP-IX administrated mice and HO-1 silent cells. Consistent results were observed in the NASH Patients. CONCLUSIONS: HO-1 could serve as a protective factor in the progression of nutritional steatohepatitis by suppresses hepatocyte excessive ER stress and might be a potential target for therapy of nonalcoholic steatohepatitis.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Heme Oxigenase-1/genética , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose/fisiologia , Células Cultivadas , Progressão da Doença , Hemina/administração & dosagem , Hepatócitos/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Hepatopatia Gordurosa não Alcoólica/genética , Protoporfirinas/administração & dosagem
10.
Life Sci ; 254: 117795, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32417373

RESUMO

AIMS: The primary focus of this study was to explore the effects of cyclic AMP response element-binding protein H (CREBH) on the development of nonalcoholic fatty liver disease (NAFLD). MATERIALS AND METHODS: CREBH knockout (KO) and wildtype (WT) mice were averagely divided into a methionine and choline-deficient (MCD) or high fat (HF) diet group and respective chow diet (CD) groups. Mice were sacrificed after 4-week treatment for MCD model and 24-week treatment for HF model. KEY FINDINGS: Characteristics of nonalcoholic steatohepatitis-related liver fibrosis in KO-MCD/HF group were verified by hepatic histological analyses. Compared with WT-MCD/HF group, levels of plasma ALT and hepatic hydroxyproline increased in KO-MCD/HF group. Significantly higher levels of MCP-1, αSMA, Desmin, COL-1, TIMP-1, TGF-ß1, TGF-ß2 were found while MMP-9 and FGF21 mRNA levels decreased in KO-MCD/HF group. There was also a distinct difference of mRNA levels of TNFα, CTGF and CCND1 in KO-HF group compared with controls. Protein levels of MCP-1, BAX, αSMA, COL-1, TGF-ß1 and SMAD2/3 significantly increased in KO-MCD/HF group and CCND1 was also upregulated in KO-HF group compared to their counterparts. SIGNIFICANCE: CREBH knockout may primarily regulate the TGF-ß1 signaling pathway via TGF-ß2 and FGF21 resulting in more severe inflammation and fibrosis in NAFLD.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Cirrose Hepática/genética , Hepatopatia Gordurosa não Alcoólica/genética , Fator de Crescimento Transformador beta/metabolismo , Alanina Transaminase/sangue , Animais , Deficiência de Colina , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/deficiência , Dieta Hiperlipídica , Fatores de Crescimento de Fibroblastos/biossíntese , Hidroxiprolina/metabolismo , Lipídeos/sangue , Cirrose Hepática/sangue , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Metionina/deficiência , Camundongos , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Transdução de Sinais/genética
11.
PLoS One ; 15(5): e0233087, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32407372

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is a pathological condition caused by excess triglyceride deposition in the liver. The SMXA-5 severe fatty liver mouse model has been established from the SM/J and A/J strains. To explore the genetic factors involved in fatty liver development in SMXA-5 mice, we had previously performed quantitative trait locus (QTL) analysis, using (SM/J×SMXA-5)F2 intercross mice, and identified Fl1sa on chromosome 12 (centromere-53.06 Mb) as a significant QTL for fatty liver. Furthermore, isoamyl acetate-hydrolyzing esterase 1 homolog (Iah1) was selected as the most likely candidate gene for Fl1sa. Iah1 gene expression in fatty liver-resistant A/J-12SM mice was significantly higher than in fatty liver-susceptible A/J mice. These data indicated that the Iah1 gene might be associated with fatty liver development. However, the function of murine Iah1 remains unknown. Therefore, in this study, we created Iah1 knockout (KO) mice with two different backgrounds [C57BL/6N (B6) and A/J-12SM (A12)] to investigate the relationship between Iah1 and liver lipid accumulation. Liver triglyceride accumulation in Iah1-KO mice of B6 or A12 background did not differ from their respective Iah1-wild type mice under a high-fat diet. These results indicated that loss of Iah1 did not contribute to fatty liver. On the other hands, adipose tissue dysfunction causes lipid accumulation in ectopic tissues (liver, skeletal muscle, and pancreas). To investigate the effect of Iah1 deficiency on white adipose tissue, we performed DNA microarray analysis of epididymal fat in Iah1-KO mice of A12 background. This result showed that Iah1 deficiency might decrease adipokines Sfrp4 and Metrnl gene expression in epididymal fat. This study demonstrated that Iah1 deficiency did not cause liver lipid accumulation and that Iah1 was not a suitable candidate gene for Fl1sa.


Assuntos
Hidrolases de Éster Carboxílico/genética , Deleção de Genes , Metabolismo dos Lipídeos , Hepatopatia Gordurosa não Alcoólica/genética , Adiposidade , Animais , Peso Corporal , Hidrolases de Éster Carboxílico/metabolismo , Colesterol/sangue , Dieta Hiperlipídica , Epididimo/metabolismo , Regulação Enzimológica da Expressão Gênica , Metabolismo dos Lipídeos/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Triglicerídeos/sangue
12.
Life Sci ; 252: 117601, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32304762

RESUMO

AIM: This work was to investigate the relationship between ApoE and autophagy regulated by AMPK/mTOR pathway in the pathological process of NAFLD. MAIN METHODS: Both WT and ApoE-/- mice were divided into two groups and allocated into either a normal chow (ND) or a high-fat diet (HFD) for 8 weeks. After that, we detected the indicators of lipid accumulation, hepatic injury, mitochondrial function hallmark, autophagy, apoptosis, inflammation, and oxidative stress by commercially available kits, immunohistochemistry, immunofluorescent staining, and western blot. KEY FINDING: We found the lipid levels of serum and liver, and hepatic injury were significantly increased in the ApoE-/--HFD group compared to other groups. ApoE-/- mice exhibited increased deposition of fat in liver tissue. The PGC1α, NRF1, ATP, p-AMPK, AMPK, Beclin1, and LC3 levels were downregulated and ROS, p-mTOR, and mTOR were increased in the ApoE-/--HFD group compared to WT-HFD group. When treated with AMPK and autophagy activators, AICAR and rapamycin, these pathologies and protein levels can be rescued. The expression levels of apoptosis-related proteins, inflammation, and oxidative stress were increased in the ApoE-/--HFD group compared to the WT-HFD group. SIGNIFICANCE: Our results indicated that ApoE deficiency can regulate AMPK/mTOR pathway, which leads to NAFLD most likely by modulating hepatic mitochondrial function.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Apolipoproteínas E/genética , Autofagia/genética , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Apoptose/genética , Dieta Hiperlipídica , Modelos Animais de Doenças , Feminino , Inflamação/genética , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Mitocôndrias/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Estresse Oxidativo/genética
13.
Indian J Gastroenterol ; 39(1): 84-91, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32333362

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is often associated with metabolic syndrome (type 2 diabetes, hypertension, hypertriglyceridemia, insulin resistance, and obesity). NAFLD is multi-factorial in pathogenesis with some genetic predisposition. The variant patatin-like phospholipase domain-containing protein 3 (PNPLA3) is known to be an independent risk factor for hepatocellular cancer (HCC). The aim of this study was to investigate the role of PNPLA3 polymorphism as the risk factor for NAFLD. METHODOLOGY: Patients had histological, ultrasonographic, biopsy evidence of NAFLD (n=248) and 81 controls were studied for PNPLA3 polymorphism. PNPLA3 genotyping was done from peripheral blood DNA by real-time polymerase chain reaction (RT-PCR). RESULTS: PNPLA3 genotyping of the groups NAFLD (CC [n = 76], CG [n = 83], GG [n = 89]) and control (CC [n= 42], CG [n = 22], GG [n = 17]) was determined. In the patient group, the G allele was 261 (52.63%) and the C allele was 235 (47.37%), whereas in the control group, the G allele was 56 (34.54%) and the C allele was 106 (65.43%). In our study, 53 out of 174 women had GG allele and 54 out of 155 men had GG allele. CONCLUSION: The findings suggest that there is a predominant relationship between men with PNPLA3 I148M variant with NAFLD in women. Patients with NAFLD carrying PNPLA3 rs738409 G>C variant are at higher risk of NAFLD.


Assuntos
Lipase/genética , Proteínas de Membrana/genética , Mutação , Hepatopatia Gordurosa não Alcoólica/genética , Carcinoma Hepatocelular , Decepção , Humanos , Neoplasias Hepáticas , Síndrome Metabólica , Fatores de Risco
14.
Rev Med Suisse ; 16(687): 586-591, 2020 Mar 25.
Artigo em Francês | MEDLINE | ID: mdl-32216182

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is one of the most prevalent liver diseases with an epidemiology correlated to obesity and metabolic syndrome. The last decade was rich of significant advances in understanding the pathophysiology of the disease, linking environmental elements, genetic factors and microbiota modifications, as well as in staging, screening and therapeutic development. The purpose of this article is to summarize recent advances in the field of NAFLD, on her way to become the first cause of cirrhosis and liver transplantation worldwide.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Cirrose Hepática/etiologia , Transplante de Fígado , Síndrome Metabólica/complicações , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/terapia , Obesidade/complicações
15.
Gene ; 742: 144549, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32184169

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most frequent liver disease and associated with a wide spectrum of hepatic disorders ranging from nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH), cirrhosis, and hepatocellular carcinoma (HCC). NASH is projected to become the most common indication for liver transplantation, and the annual incidence rate of NASH-related HCC is 5.29 cases per 1000 person-years. Owing to the epidemics of NAFLD and the unclear mechanism of NAFLD progression, it is important to elucidate the underlying NAFLD mechanisms in detail. NASH is mainly caused by the development of NAFL Therefore, it is also of great significance to understand the mechanism of progression from NAFL to NASH. Gene expression chip data for NAFLD and NASH were downloaded from the Gene Expression Omnibus database to identify differentially expressed genes (DEGs) between NAFLD and normal controls (called DEGs for NAFLD), as well as between NASH and normal tissue (called DEGs for NASH-Normal), and between NASH and NAFL tissue (called DEGs for NASH-NAFL). For DEGs for the NAFLD group, key genes were identified by studying the form of intersection. Potential functions of DEGs for NASH were then analyzed by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. A protein-protein interaction network (PPI) was constructed using the STRING database. A total of 249 DEGs and one key gene for NAFLD were identified. For NASH-Normal, 514 DEGs and 11 hub genes were identified, three of which were closely related to the survival analysis of HCC, and potentially closely related to progression from NASH to HCC. One key gene for NASH-NAFL (AKR1B10) was identified. These genes appear to mediate the molecular mechanism underlying NAFLD and may be promising biomarkers for the presence of NASH.


Assuntos
Aldo-Ceto Redutases/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Hepatopatia Gordurosa não Alcoólica/genética , Aldo-Ceto Redutases/metabolismo , Biomarcadores/metabolismo , Carcinoma Hepatocelular/genética , Biologia Computacional , Conjuntos de Dados como Assunto , Diagnóstico Diferencial , Progressão da Doença , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Neoplasias Hepáticas/genética , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Mapas de Interação de Proteínas/genética
16.
Rev. Hosp. Ital. B. Aires (2004) ; 40(1): 17-24, mar. 2020. ilus
Artigo em Espanhol | LILACS | ID: biblio-1100762

RESUMO

Se estima que aproximadamente 100 trillones de microorganismos (incluidos bacterias, virus y hongos) residen en el intestino humano adulto y que el total del material genético del microbioma es 100 veces superior al del genoma humano. Esta comunidad, conocida como microbioma se adquiere al momento del nacimiento a través de la flora comensal de la piel, vagina y heces de la madre y se mantiene relativamente estable a partir de los dos años desempeñando un papel crítico tanto en el estado de salud como en la enfermedad. El desarrollo de nuevas tecnologías, como los secuenciadores de próxima generación (NGS), permiten actualmente realizar un estudio mucho más preciso de ella que en décadas pasadas cuando se limitaba a su cultivo. Si bien esto ha llevado a un crecimiento exponencial en las publicaciones, los datos sobre las poblaciones Latinoamérica son casi inexistentes. La investigación traslacional en microbioma (InTraMic) es una de las líneas que se desarrollan en el Instituto de Medicina Traslacional e Ingeniería Biomédica (IMTIB). Esta se inició en 2018 con la línea de cáncer colorrectal (CCR) en una colaboración con el Colorectal Cancer Research Group del Leeds Institute of Medical Research en el proyecto Large bowel microbiome disease network: Creation of a proof of principle exemplar in colorectal cancer across three continents. A fines de 2019 se cumplió el objetivo de comprobar la factibilidad de la recolección, envío y análisis de muestras de MBF en 5 continentes, incluyendo muestras provenientes de la Argentina, Chile, India y Vietnam. Luego de haber participado de capacitaciones en Inglaterra, se ha cumplido con el objetivo de la etapa piloto, logrando efectivizar la recolección, envío y análisis metagenómico a partir de la secuenciación de la región V4 del ARNr 16S. En 2019, la línea de enfermedad de hígado graso no alcohólico se sumó a la InTraMic iniciando una caracterización piloto en el marco de una colaboración con el laboratorio Novartis. Los resultados de ese estudio, así como el de cáncer colorrectal, están siendo enviados a publicación. En 2020, con la incorporación de la línea de trasplante alogénico de células progenitoras hematopoyéticas, fue presentado un proyecto para un subsidio del CONICET que ha superado la primera etapa de evaluación. En el presente artículo se brinda una actualización sobre la caracterización taxonómica de microbioma y se describen las líneas de investigación en curso. (AU)


It is estimated that approximately 100 trillion microorganisms (including bacteria, viruses, and fungi) reside in the adult human intestine, and that the total genetic material of the microbiome is 100 times greater than that of the human genome. This community, known as the microbiome, is acquired at birth through the commensal flora of the mother's skin, vagina, and feces and remains relatively stable after two years, playing a critical role in both the state of health and in disease. The development of new technologies, such as next-generation sequencers (NGS), currently allow for a much more precise study of it than in past decades when it was limited to cultivation. Although this has led to exponential growth in publications, data on Latin American populations is almost non-existent. Translational research in microbiome (InTraMic) is one of the lines developed at the Instituto de Medicina Traslacional e Ingeniería Biomédica (IMTIB). This started in 2018 with the Colorectal Cancer Line (CRC) in a collaboration with the Colorectal Cancer Research Group of the Leeds Institute of Medical Research in the project "Large bowel microbiome disease network: Creation of a proof of principle exemplar in colorectal cancer across three continents". At the end of 2019, the objective of verifying the feasibility of collecting, sending and analyzing MBF samples on 5 continents, including samples from Argentina, Chile, India and Vietnam, was met. After having participated in training in England, the objective of the pilot stage has been met, achieving the collection, delivery and metagenomic analysis from the sequencing of the V4 region of the 16S rRNA. In 2019, the non-alcoholic fatty liver disease line joined InTraMic, initiating a pilot characterization in the framework of a collaboration with the Novartis laboratory. The results of that study, as well as that of colorectal cancer, are being published. In 2020, with the incorporation of the allogeneic hematopoietic stem cell transplantation line, a project was presented for a grant from the CONICET that has passed the first stage of evaluation. This article provides an update on the taxonomic characterization of the microbiome and describes the lines of ongoing research. (AU)


Assuntos
Humanos , Pesquisa Médica Translacional/organização & administração , Microbioma Gastrointestinal/genética , Transplante Homólogo , Vietnã , Aztreonam/uso terapêutico , RNA Ribossômico 16S/análise , Neoplasias Colorretais/genética , Neoplasias Colorretais/microbiologia , Neoplasias Colorretais/epidemiologia , Classificação/métodos , Transplante de Células-Tronco Hematopoéticas , Metagenômica , Pesquisa Médica Translacional/métodos , Sequenciamento de Nucleotídeos em Larga Escala/tendências , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/microbiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Microbioma Gastrointestinal/fisiologia , Índia , América Latina , Sangue Oculto
17.
Biochim Biophys Acta Mol Basis Dis ; 1866(6): 165753, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32126269

RESUMO

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is associated to intermittent hypoxia (IH) and is an aggravating factor of non-alcoholic fatty liver disease (NAFLD). We investigated the effects of hypoxia in both in vitro and in vivo models of NAFLD. METHODS: Primary rat hepatocytes treated with free fatty acids (FFA) were subjected to chemically induced hypoxia (CH) using the hypoxia-inducible factor-1 alpha (HIF-1α) stabilizer cobalt chloride (CoCl2). Triglyceride (TG) content, mitochondrial superoxide production, cell death rates, cytokine and inflammasome components gene expression and protein levels of cleaved caspase-1 were assessed. Also, Kupffer cells (KC) were treated with conditioned medium (CM) and extracellular vehicles (EVs) from hypoxic fat-laden hepatic cells. The choline deficient L-amino acid defined (CDAA)-feeding model used to assess the effects of IH on experimental NAFLD in vivo. RESULTS: Hypoxia induced HIF-1α in cells and animals. Hepatocytes exposed to FFA and CoCl2 exhibited increased TG content and higher cell death rates as well as increased mitochondrial superoxide production and mRNA levels of pro-inflammatory cytokines and of inflammasome-components interleukin-1ß, NLRP3 and ASC. Protein levels of cleaved caspase-1 increased in CH-exposed hepatocytes. CM and EVs from hypoxic fat-laden hepatic cells evoked a pro-inflammatory phenotype in KC. Livers from CDAA-fed mice exposed to IH exhibited increased mRNA levels of pro-inflammatory and inflammasome genes and increased levels of cleaved caspase-1. CONCLUSION: Hypoxia promotes inflammatory signals including inflammasome/caspase-1 activation in fat-laden hepatocytes and contributes to cellular crosstalk with KC by release of EVs. These mechanisms may underlie the aggravating effect of OSAS on NAFLD. [Abstract word count: 257].


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Hipóxia/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Hepatopatia Gordurosa não Alcoólica/genética , Apneia Obstrutiva do Sono/genética , Animais , Caspase 1/genética , Deficiência de Colina/genética , Deficiência de Colina/metabolismo , Deficiência de Colina/patologia , Cobalto/toxicidade , Modelos Animais de Doenças , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patologia , Ácidos Graxos não Esterificados/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Hipóxia/induzido quimicamente , Hipóxia/metabolismo , Hipóxia/patologia , Inflamassomos/genética , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Interleucina-1beta/genética , Macrófagos do Fígado/metabolismo , Macrófagos do Fígado/patologia , Camundongos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Ratos , Apneia Obstrutiva do Sono/etiologia , Apneia Obstrutiva do Sono/metabolismo , Apneia Obstrutiva do Sono/patologia , Triglicerídeos/genética
18.
Nat Commun ; 11(1): 962, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075973

RESUMO

Metabolic adaptation to nutritional state requires alterations in gene expression in key tissues. Here, we investigated chromatin interaction dynamics, as well as alterations in cis-regulatory loci and transcriptional network in a mouse model system. Chronic consumption of a diet high in saturated fat, when compared to a diet high in carbohydrate, led to dramatic reprogramming of the liver transcriptional network. Long-range interaction of promoters with distal regulatory loci, monitored by promoter capture Hi-C, was regulated by metabolic status in distinct fashion depending on diet. Adaptation to a lipid-rich diet, mediated largely by nuclear receptors including Hnf4α, relied on activation of preformed enhancer/promoter loops. Adaptation to carbohydrate-rich diet led to activation of preformed loops and to de novo formation of new promoter/enhancer interactions. These results suggest that adaptation to nutritional changes and metabolic stress occurs through both de novo and pre-existing chromatin interactions which respond differently to metabolic signals.


Assuntos
Dieta , Redes Reguladoras de Genes/genética , Fígado/metabolismo , Regiões Promotoras Genéticas/genética , Animais , Cromatina/genética , Cromatina/metabolismo , Imunoprecipitação da Cromatina , Dieta/efeitos adversos , Elementos Facilitadores Genéticos/genética , Regulação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/genética , Obesidade/metabolismo , Fatores de Transcrição/genética , Transcriptoma
19.
J Agric Food Chem ; 68(9): 2673-2683, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32050765

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is rapidly becoming the leading cause of chronic liver diseases throughout the world. The deficit of pharmacotherapy for NAFLD calls for an urgent need for a new drug discovery and lifestyle management. Black tea is the most popular and functional drink consumed worldwide. Its main bioactive constituent theaflavin helps to prevent obesity-a major risk factor for NAFLD. To find new targets for the development of effective and safe therapeutic drugs from natural plants for NAFLD, we found a theaflavin monomer theaflavin-3,3'-digallate (TF3), which significantly reduced lipid droplet accumulation in hepatocytes, and directly bound and inhibited the activation of plasma kallikrein (PK), which was further proved to stimulate adenosine monophosphate activated protein kinase (AMPK) and its downstream targets. Taken together, we proposed that the TF3-PK-AMPK regulatory axis is a novel mechanism of lipid deposition mitigation, and PK could be a new target for NAFLD treatment.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Biflavonoides/farmacologia , Catequina/farmacologia , Hepatócitos/metabolismo , Gotículas Lipídicas/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Extratos Vegetais/farmacologia , Calicreína Plasmática/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Apoptose/efeitos dos fármacos , Camellia sinensis/química , Células Hep G2 , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Transdução de Sinais/efeitos dos fármacos
20.
Nat Commun ; 11(1): 719, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024826

RESUMO

Lipid overload results in lipid redistribution among metabolic organs such as liver, adipose, and muscle; therefore, the interplay between liver and other organs is important to maintain lipid homeostasis. Here, we show that liver responds to lipid overload first and sends hepatocyte-derived extracellular vesicles (EVs) targeting adipocytes to regulate adipogenesis and lipogenesis. Geranylgeranyl diphosphate synthase (Ggpps) expression in liver is enhanced by lipid overload and regulates EV secretion through Rab27A geranylgeranylation. Consistently, liver-specific Ggpps deficient mice have reduced fat adipose deposition. The levels of several EV-derived miRNAs in the plasma of non-alcoholic fatty liver disease (NAFLD) patients are positively correlated with body mass index (BMI), and these miRNAs enhance adipocyte lipid accumulation. Thus, we highlight an inter-organ mechanism whereby the liver senses different metabolic states and sends corresponding signals to remodel adipose tissue to adapt to metabolic changes in response to lipid overload.


Assuntos
Tecido Adiposo/metabolismo , Vesículas Extracelulares/metabolismo , Hepatócitos/metabolismo , Metabolismo dos Lipídeos/fisiologia , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/sangue , Adipócitos/metabolismo , Adipócitos/patologia , Tecido Adiposo/patologia , Animais , Índice de Massa Corporal , Dieta Hiperlipídica/efeitos adversos , Vesículas Extracelulares/genética , Farnesiltranstransferase/genética , Humanos , Lipogênese , Fígado/citologia , Fígado/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/sangue , Complexos Multienzimáticos/genética , Hepatopatia Gordurosa não Alcoólica/genética , Proteínas rab27 de Ligação ao GTP/genética , Proteínas rab27 de Ligação ao GTP/metabolismo
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