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1.
Front Immunol ; 14: 1253649, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37818371

RESUMO

Introduction: Scurfy mice have a complete deficiency of functional regulatory T cells (Treg) due to a frameshift mutation in the Foxp3 gene. The impaired immune homeostasis results in a lethal lymphoproliferative disorder affecting multiple organs, including the liver. The autoimmune pathology in scurfy mice is in part accompanied by autoantibodies such as antinuclear antibodies (ANA). ANA are serological hallmarks of several autoimmune disorders including autoimmune liver diseases (AILD). However, the underlying pathogenesis and the role of Treg in AILD remain to be elucidated. The present study therefore aimed to characterize the liver disease in scurfy mice. Methods: Sera from scurfy mice were screened for ANA by indirect immunofluorescence assay (IFA) and tested for a wide range of AILD-associated autoantibodies by enzyme-linked immunosorbent assay, line immunoassay, and addressable laser bead immunoassay. CD4+ T cells of scurfy mice were transferred into T cell-deficient B6/nude mice. Monoclonal autoantibodies from scurfy mice and recipient B6/nude mice were tested for ANA by IFA. Liver tissue of scurfy mice was analyzed by conventional histology. Collagen deposition in scurfy liver was quantified via hepatic hydroxyproline content. Real-time quantitative PCR was used to determine fibrosis-related hepatic gene expression. Hepatic immune cells were differentiated by flow cytometry. Results: All scurfy mice produced ANA. AILD-associated autoantibodies, predominantly antimitochondrial antibodies, were detected at significantly higher levels in scurfy sera. CD4+ T cells from scurfy mice were sufficient to induce anti-dsDNA autoantibodies and ANA with an AILD-related nuclear envelope staining pattern. Liver histology revealed portal inflammation with bile duct damage and proliferation, as in primary biliary cholangitis (PBC), and interface hepatitis with portal-parenchymal necroinflammation, as found in autoimmune hepatitis (AIH). In scurfy liver, TNFα and fibrosis-related transcripts including Col1a1, Timp1, Acta2, Mmp2, and Mmp9 were upregulated. The level of proinflammatory monocytic macrophages (Ly-6Chi) was increased, while M2-type macrophages (CD206+) were downregulated compared to wildtype controls. Despite severe hepatic inflammation, fibrosis did not develop within 25 days, which is close to the lifespan of scurfy mice. Discussion: Our findings suggest that Treg-deficient scurfy mice spontaneously develop clinical, serological, and immunopathological characteristics of AILD with overlapping features of PBC and AIH.


Assuntos
Doenças do Tecido Conjuntivo , Hepatite Autoimune , Hepatopatias , Camundongos , Animais , Linfócitos T Reguladores , Camundongos Nus , Autoanticorpos , Hepatopatias/metabolismo , Fibrose , Doenças do Tecido Conjuntivo/metabolismo , Síndrome , Inflamação/metabolismo
2.
J Multidiscip Healthc ; 16: 411-418, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36820220

RESUMO

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a highly contagious viral infection. In addition to its association with common pulmonary and gastrointestinal complications, COVID-19 is also associated with numerous neurological and neuropsychiatric conditions. This minireview aims to cover current literature addressing the application of telemedicine in neurological disorders and neuropsychiatric conditions, especially in response to the COVID-19 pandemic. This article revealed that quarantine, masking, and social distancing policies practiced during the COVID-19 pandemic involved restrictions and challenges to providing medical services, especially for patients with neurological disorders with or without COVID-19 infection. During the pandemic, both healthcare administrators and clinicians, including neurologists, have rapidly adapted or introduced telemedicine technologies for delivering specialty care. In some areas in the world, telemedicine has been successfully applied to reduce the impact imposed by COVID-19. Conclusively, this article supports the idea that telemedicine is an effective tool for providing specialized healthcare for patients with neurological conditions while adhering to social distancing or lockdown policies instituted during the COVID-19 pandemic. Government and medical/healthcare authorities, physicians and healthcare providers need to work together to expand the adoption of telemedicine applications, even after the COVID-19 crisis.

3.
Medicine (Baltimore) ; 99(21): e19887, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32481254

RESUMO

INTRODUCTION: Spontaneous bacterial peritonitis (SBP) is a fatal infection in patients. It often happens in patients with cirrhosis, cancer or diabetes, and is caused mostly by Enterobacteriaceae. Here we report a rare case of SBP caused by Campylobacter Coli (C coli) infection, which was identified promptly by the matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and received adequate therapy sooner after. PATIENT CONCERNS: In the present study, we reported a 46-year-old male with alcoholic liver cirrhosis (Child-Pugh class C) and type 2 diabetes mellitus presented with a 1-day history of fever and abdominal pain. DIAGNOSIS: Based on the clinical examinations, the patient was diagnosed with SBP and the pathogen was quickly identified as C coli by the matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), a rare causative pathogen of SBP. INTERVENTIONS: The patient received a 10-day antibiotic treatment with Ciprofloxacin 400 mg every 12 hours, and recovered successfully. OUTCOMES: The patient had a successful treatment outcome. CONCLUSION: The study demonstrated a new possible infectious cause of SBP by C Coli, which was rarely seen in liver cirrhosis but mostly found in immunocompromised patients. Thus, it might raise an idea of microorganism screening of broader types that might also induce SBP for immunocompromised patients.


Assuntos
Infecções por Campylobacter/complicações , Campylobacter coli , Cirrose Hepática/complicações , Peritonite/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade
4.
Medicine (Baltimore) ; 99(18): e19738, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32358347

RESUMO

RATIONALE: Scrotal swelling is a rare complication of acute pancreatitis. It had been explained by fluid accumulation in scrotum originated from abdomen. Here we demonstrated a case of recurrent pancreatitis with hydrocele caused by impaired testicular venous drainage. PATIENT CONCERNS: A 53-year-old man presented with sudden onset epigastric pain after an alcohol binge. Recurrent acute pancreatitis was confirmed by medical history, physical examination, elevated lipase level and abdominal computed tomography (CT) scan. Right scrotal swelling was noticed on the next day. DIAGNOSIS: The scrotal ultrasonography demonstrated fluid accumulation around the testis and varicocele consistent with scrotal hydrocele. CT scans of the abdomen and pelvis showed encasement of the right testicular vein by pancreatic phlegmon. INTERVENTIONS: The patient was subject to Nulla per os, hydration, and opioid analgesics for pancreatitis. No intervention was performed for scrotal swelling. OUTCOMES: Hydrocele gradually resolved along with acute pancreatitis. LESSONS: Pancreatic phlegmon compromised testicular venous return which led to scrotal hydrocele and posed a threat to fertility. The study has provided a novel pathologic linkage. This complication should be taken into account.


Assuntos
Pancreatite/etiologia , Hidrocele Testicular/etiologia , Testículo/irrigação sanguínea , Doenças Vasculares/complicações , Doença Aguda , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva
6.
Artigo em Inglês | MEDLINE | ID: mdl-31936779

RESUMO

Lecca et al., in a recent publication in the Int. J. Environ. Res. Public Health had made some mistakes in the statistical analysis and interpretation of the results. Age was not a clear contributing factor in the prolongation of QT interval in the electrocardiogram (ECG), as there were strong confounders in their study. The effects of age were mainly faded out because of the age range of the participants. The use of Pearson's correlation is questionable because of the normality assumptions was not met on the studied variables. They also made some conclusions about the effects of long and night shifts on the QT prolongation that were not appropriate based on their study type. All of these mentioned issues might completely change the validity of the conclusions they made.


Assuntos
Estresse Ocupacional , Saúde Pública , Eletrocardiografia , Humanos , Masculino
7.
Medicina (Kaunas) ; 55(10)2019 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-31569560

RESUMO

Background and objectives: Chronic kidney disease (CKD) is an independent risk factor for cardiovascular disease (CVD). Previous studies reported controversial results about the independence of CKD as a risk factor for atherosclerosis. In this study, we tried to determine whether the estimated glomerular filtration rate (eGFR) and other renal function tests are independent factors associated with arterial stiffness in community-dwelling individuals with a normal (≥90) or slightly decreased eGFR (60-90). Materials and Methods: Data of 164 community individuals were analyzed, and demographic information, related disease history, atherosclerosis risk factors, certain laboratory tests, the estimated eGFR, and urine albumin creatinine ratio (UACR) were recorded for each individual. Results: The age, systolic blood pressure (SBP), hypertension (HTN), and cardio-ankle vascular index (CAVI) significantly differed between individuals with a normal and those with a slightly decreased eGFR. Blood urea nitrogen (BUN), glycated hemoglobin (HBA1c), and the eGFR significantly differed between the high- and low-CAVI groups and were also significantly correlated with the CAVI. The relationship between the eGFR and CAVI was shown to be independent of other atherosclerosis risk factors in a multiple linear regression model. Conclusions: We concluded that evaluations of the eGFR, HTN, body-mass index, and SBP can be used in a model for arterial stiffness risk assessments for community-dwelling individuals with a normal or slightly decreased eGFR.


Assuntos
Índice Tornozelo-Braço , Taxa de Filtração Glomerular/fisiologia , Rigidez Vascular/fisiologia , Idoso , Aterosclerose/diagnóstico , Aterosclerose/etiologia , Aterosclerose/fisiopatologia , Feminino , Humanos , Hipertensão/diagnóstico , Vida Independente/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Insuficiência Renal Crônica/complicações , Medição de Risco
8.
Oncogene ; 38(3): 317-331, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30097606

RESUMO

Aged hepatocyte-specific-Mcl-1 knockout (MKO-hep) mice are prone to develop liver tumors mimicking human hepatocellular carcinoma (HCC). Here we reported that a protein named UDP-N-acetylglucosamine pyrophosphorylase-1-like-1 (Uap1l1) is upregulated in the liver of young MKO-hep mice without any macroscopically detectable tumor nodules and is prominently expressed in the hepatic tumors developed in the aged MKO-hep mice. Intriguingly, human UAP1L1 is also significantly upregulated in a distinct subset of HCC tissues and patients with upregulated expression of UAP1L1 appeared to have poor prognosis. Overexpression of UAP1L1 significantly promoted, whereas UAP1L1 knockdown markedly reduced the proliferation of human hepatoma cells both in vitro and in vivo. UAP1L1 shows ~59% sequence identity to UDP-N-acetylglucosamine pyrophosphorylase-1 (UAP1), which is directly involved in the synthesis of the sugar donor (UDP-GlcNac) for N-acetylglucosamine modification (O-GlcNAcylation) of proteins. However, unlike UAP1, UAP1L1 harbors very limited UDP-GlcNAc synthesis activity. Moreover, although both UAP1 and UAP1L1 are required for O-GlcNAc transferase (OGT)-mediated protein O-GlcNAcylation, they appear to function distinctly from each other. UAP1L1 directly interacts with OGT, but does not seem to be an OGT substrate. In addition, UAP1L1 alone is not sufficient to activate OGT activity in vitro, suggesting that UAP1L1 may function together with other proteins to modulate OGT activity in vivo. Lastly, UAP1L1 knockdown attenuated c-MYC O-GlcNAcylation and protein stability, and overexpression of c-MYC significantly rescued the proliferation defect of UAP1L1 knockdown HepG2 cells, suggesting that c-MYC is one downstream target of UAP1L1 that contributes to UAP1L1-mediated cell proliferation, at least in HepG2 cells.


Assuntos
Carcinoma Hepatocelular/enzimologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/enzimologia , Proteínas de Neoplasias/fisiologia , Nucleotidiltransferases/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Animais , Carcinoma Hepatocelular/patologia , Divisão Celular , Ativação Enzimática , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Glicosilação , Células Hep G2 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas Experimentais/enzimologia , Neoplasias Hepáticas Experimentais/patologia , Camundongos , N-Acetilglucosaminiltransferases/metabolismo , Nucleotidiltransferases/genética , Prognóstico , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transcriptoma , Regulação para Cima
9.
EBioMedicine ; 29: 92-103, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29463471

RESUMO

Chronic hepatitis leads to liver fibrosis and cirrhosis. Cirrhosis is a major cause of worldwide morbidity and mortality. Macrophages play a key role in fibrosis progression and reversal. However, the signals that determine fibrogenic vs fibrolytic macrophage function remain ill defined. We studied the role of interleukin-4 receptor α (IL-4Rα), a potential central switch of macrophage polarization, in liver fibrosis progression and reversal. We demonstrate that inflammatory monocyte infiltration and liver fibrogenesis were suppressed in general IL-4Rα-/- as well as in macrophage-specific IL-4Rα-/- (IL-4RαΔLysM) mice. However, with deletion of IL-4RαΔLysM spontaneous fibrosis reversal was retarded. Results were replicated by pharmacological intervention using IL-4Rα-specific antisense oligonucleotides. Retarded resolution was linked to the loss of M2-type resident macrophages, which secreted MMP-12 through IL-4 and IL-13-mediated phospho-STAT6 activation. We conclude that IL-4Rα signaling regulates macrophage functional polarization in a context-dependent manner. Pharmacological targeting of macrophage polarization therefore requires disease stage-specific treatment strategies. RESEARCH IN CONTEXT: Alternative (M2-type) macrophage activation through IL-4Rα promotes liver inflammation and fibrosis progression but speeds up fibrosis reversal. This demonstrates context dependent, opposing roles of M2-type macrophages. During reversal IL-4Rα induces fibrolytic MMPs, especially MMP-12, through STAT6. Liver-specific antisense oligonucleotides efficiently block IL-4Rα expression and attenuate fibrosis progression.


Assuntos
Subunidade alfa de Receptor de Interleucina-4/metabolismo , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Macrófagos/metabolismo , Transdução de Sinais , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Expressão Gênica , Subunidade alfa de Receptor de Interleucina-4/genética , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/etiologia , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Knockout , Células Mieloides/imunologia , Células Mieloides/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Células RAW 264.7 , Fator de Transcrição STAT6/metabolismo , Baço/imunologia , Baço/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
10.
Antioxid Redox Signal ; 28(2): 87-109, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-28635324

RESUMO

AIMS: Nonalcoholic steatohepatitis (NASH) is characterized by steatosis, panlobular inflammation, liver fibrosis, and increased cardiovascular mortality. Dipeptidyl peptidase-4 inhibitors (gliptins) are indirect glucagon-like peptide 1 agonists with antidiabetic and anti-inflammatory activity, used for the treatment of type 2 diabetes. Their potential and underlying mechanisms to treat metabolic liver inflammation and fibrosis as well as the associated vascular dysfunction remain to be explored. RESULTS: In the methionine/choline-deficient (MCD) diet and Mdr2-/- models of NASH and liver fibrosis, treatment with sitagliptin and linagliptin significantly decreased parameters of steatosis and inflammation, which was accompanied by suppression of hepatic transcript levels reflecting metabolic inflammation and fibrosis, including SREBP-1c, FAS, TNFα, iNOS, α-SMA, Col1α1, and MMP-12. Moreover, gliptins reduced the number of liver infiltrating CD11b+Ly6Chi proinflammatory monocytes/macrophages and liver-resident F4/80+ macrophages, with an increase of Ym1+ alternative macrophages and (anti-inflammatory) macrophage markers Arg1 and IL-10. This was paralleled by decreased hepatic and aortic reactive oxygen species (ROS) production and NOX-2 mRNA expression, a normalization of endothelial dysfunction, cardiac NADPH oxidase activity, mitochondrial ROS formation, and whole blood oxidative burst in the MCD model. Innovation and Conclusions: Gliptins via suppression of inflammation decrease steatosis, apoptosis, oxidative stress, and vascular dysfunction in murine models of NASH and liver fibrosis, with mild direct antifibrotic properties. They reduce the numbers of liver and vascular inflammatory monocytes/macrophages and induce their alternative polarization, with beneficial effect on NASH-associated hepatic and cardiovascular complications. Therefore, gliptins qualify as drugs for treatment of NASH and associated liver fibrosis and cardiovascular complications. Antioxid. Redox Signal. 28, 87-109.


Assuntos
Inibidores da Dipeptidil Peptidase IV/farmacologia , Inflamação/imunologia , Inflamação/metabolismo , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Biomarcadores , Dieta/efeitos adversos , Modelos Animais de Doenças , Fibrose , Expressão Gênica , Inflamação/complicações , Inflamação/patologia , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Knockout , Células Mieloides/imunologia , Células Mieloides/metabolismo , NADPH Oxidase 2/genética , NADPH Oxidase 2/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Espécies Reativas de Oxigênio/metabolismo
11.
Matrix Biol ; 66: 34-49, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29122677

RESUMO

Organ fibrosis is characterized by a chronic wound-healing response, with excess deposition of extracellular matrix components. Here, collagen type I represents the most abundant scar component and a primary target for antifibrotic therapies. Liver fibrosis can progress to cirrhosis and primary liver cancer, which are the major causes of liver related morbidity and mortality. However, a (pro-)collagen type I specific therapy remains difficult and its therapeutic abrogation may incur unwanted side effects. We therefore designed tetracycline-regulated procollagen alpha1(I) short hairpin (sh)RNA expressing mice that permit a highly efficient inducible knockdown of the procollagen alpha1(I) gene in activated (myo-)fibroblasts, to study the effect of induced procollagen type I deficiency. Transgenic mice were generated using recombinase-mediated integration in embryonic stem cells or zinc-finger nuclease-aided genomic targeting combined with miR30-shRNA technology. Liver fibrosis was induced in transgenic mice by carbon tetrachloride, either without or with doxycycline supplementation. Doxycycline treated mice showed an 80-90% suppression of procollagen alpha1(I) transcription and a 40-50% reduction in hepatic collagen accumulation. Procollagen alpha1(I) knockdown also downregulated procollagens type III, IV and VI and other fibrosis related parameters. Moreover, this was associated with an attenuation of chronic inflammation, suggesting that collagen type I serves not only as major scar component, but also as modulator of other collagens and promoter of chronic inflammation.


Assuntos
Colágeno Tipo I/genética , Proteínas da Matriz Extracelular/genética , Cirrose Hepática/prevenção & controle , Pró-Colágeno/genética , Animais , Células Cultivadas , Modelos Animais de Doenças , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Cirrose Hepática/genética , Camundongos , Camundongos Transgênicos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/efeitos dos fármacos , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/farmacologia
12.
J Dermatol Sci ; 87(3): 285-291, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28811075

RESUMO

BACKGROUND: Scurfy mice have a functional defect in regulatory T cells (Treg), which leads to lethal multi-organ inflammation. The missing Treg function results in uncontrolled autoimmune cellular and humoral inflammatory responses. We and others have previously shown that during the course of disease scurfy mice develop severe skin inflammation and autoantibodies including anti-nuclear autoantibodies (ANA). OBJECTIVE: Autoimmune skin inflammation and ANA are hallmarks for the diagnosis of autoimmune connective tissue diseases; therefore we analyzed scurfy mice for typical signs of these diseases. METHODS: Indirect immunofluorescence was used to specify the ANA pattern in scurfy mice. Skin fibrosis was assessed by cutaneous collagen accumulation (Goldeners trichrome staining), collagen crosslinking/disorganization (Sirus red polarimetry) and quantitative PCR for fibrosis-related transcripts. The cellular components of the inflammatory infiltrates in scurfy skin were analyzed by flow cytometry and intracellular cytokine staining. RESULTS: The majority of scurfy mice developed ANA with a predominant AC-5 pattern typical for mixed connective tissue disease, especially scleroderma. Scurfy mice showed higher skin collagen content compared to WT controls with a significant tendency in upregulation of TIMP-1. CD3+CD4+ T cells in scurfy skin exhibited a strong Th2 deviation with a significant increase of IL-4, IL-5 and IL-13, and M2-polarized CD11b+MHCII+ macrophages compared to WT mice. CONCLUSION: We show that Scurfy mice show a predominant AC-5 ANA pattern typical for mixed connective tissue disease as in scleroderma. The autoimmune inflammation in scurfy skin mainly consists of CD4+ T cells with Th2 differentiation and alternatively-activated (M2) macrophages as it is found in scleroderma with advanced fibrosis.


Assuntos
Anticorpos Antinucleares/imunologia , Doenças Autoimunes/imunologia , Dermatite/imunologia , Macrófagos/imunologia , Escleroderma Sistêmico/imunologia , Linfócitos T Reguladores/imunologia , Animais , Núcleo Celular/imunologia , Colágeno/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Feminino , Fibrose , Citometria de Fluxo , Imunofluorescência , Fatores de Transcrição Forkhead/genética , Ativação de Macrófagos , Macrófagos/metabolismo , Masculino , Camundongos , Escleroderma Sistêmico/genética , Escleroderma Sistêmico/patologia , Pele/imunologia , Pele/metabolismo , Pele/patologia , Linfócitos T Reguladores/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Regulação para Cima
14.
J Hepatol ; 54(4): 685-94, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21146511

RESUMO

BACKGROUND & AIMS: Mcl-1-deficient hepatocytes are prone to undergo apoptosis. The tumor suppressor protein p53 plays an important role in apoptosis control as well as other cellular responses. This study was initially aimed to examine whether p53 was involved in Mcl-1 deficiency-induced apoptosis of hepatocytes. METHODS: Hepatocyte-specific Mcl-1 knockout (Alb-Mcl-1(-/-)) mice and Alb-Mcl-1(-/-) mice in wild-type or p53-deficient background were generated and characterized. RESULTS: Alb-Mcl-1(-/-) mice were viable, but their liver cells were prone to undergo apoptosis and manifested a slightly elevated level of p53. To examine the role of p53 in Alb-Mcl-1(-/-) livers, Alb-Mcl-1(-/-) mice without p53 (DKO mice) were characterized. Unexpectedly, although p53-deficient mice appeared to be developmentally normal, DKO mice were highly susceptible to neonatal death (∼60%). Further analysis revealed that such an early lethality was likely due to hepatic failure caused by a marked reduction of fully-differentiated hepatocytes at the perinatal/neonatal stage. Moreover, those DKO mice that did survive to adulthood manifested more severe liver damage than Alb-Mcl-1(-/-) mice, suggesting that p53 was activated in Alb-Mcl-1(-/-) livers to promote cell survival. Microarray followed by quantitative PCR analysis suggested that p21(Waf1/Cip1), one p53 target gene with apoptosis-inhibitory function, is likely involved in the protective role of p53 in Alb-Mcl-1(-/-) livers. Moreover, we demonstrated that loss of p53 promoted liver fibrosis and tumor development in Alb-Mcl-1(-/-) mice. CONCLUSIONS: This study revealed an unexpected synergism between Mcl-1 and p53 in protecting from hepatic injury, fibrosis, and cancer.


Assuntos
Cirrose Hepática Experimental/prevenção & controle , Neoplasias Hepáticas Experimentais/prevenção & controle , Fígado/lesões , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Animais , Apoptose/genética , Apoptose/fisiologia , Sequência de Bases , Proliferação de Células , Primers do DNA/genética , Feminino , Genes p53 , Hepatócitos/patologia , Hepatócitos/fisiologia , Fígado/patologia , Fígado/fisiopatologia , Cirrose Hepática Experimental/genética , Cirrose Hepática Experimental/patologia , Cirrose Hepática Experimental/fisiopatologia , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/patologia , Neoplasias Hepáticas Experimentais/fisiopatologia , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Proteína de Sequência 1 de Leucemia de Células Mieloides , Gravidez , Proteínas Proto-Oncogênicas c-bcl-2/deficiência , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética
15.
Mol Biol Cell ; 18(7): 2525-32, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17475776

RESUMO

Translationally controlled Tumor Protein (TCTP) is an evolutionally highly conserved protein which has been implicated in many cellular functions that are related to cell growth, death, and even the allergic response of the host. To address the physiological roles of TCTP, we generated TCTP knockout mice by targeted gene disruption. Heterozygous mutants appeared to be developmentally normal. However, homozygous mutants (TCTP(-/-)) were embryonic lethal. TCTP(-/-) embryos were smaller in size than the control littermates at all postimplantation stages examined. Although TCTP is widely expressed in both extraembryonic and embryonic tissues, the most prominent defect of the TCTP(-/-) embryo at embryonic stage day 5.5 (E5.5) was in its epiblast, which had a reduced number of cells compared with wild-type controls. The knockout embryos also suffered a higher incidence of apoptosis in epiblast starting about E6.5 and subsequently died around E9.5-10.5 with a severely disorganized structure. Last, we demonstrated that TCTP(-/-) and control mouse embryonic fibroblasts manifested similar proliferation activities and apoptotic sensitivities to various death stimuli. Taken together, our results suggest that despite that TCTP is widely expressed in many tissues or cell types, it appears to regulate cell proliferation and survival in a tissue- or cell type-specific manner.


Assuntos
Biomarcadores Tumorais/deficiência , Biomarcadores Tumorais/metabolismo , Animais , Apoptose , Proliferação de Células , Sobrevivência Celular , Ciclinas/metabolismo , Embrião de Mamíferos/anormalidades , Feminino , Morte Fetal , Fibroblastos/citologia , Fase G1 , Fase G2 , Gástrula/metabolismo , Marcação de Genes , Masculino , Camundongos , Camundongos Knockout , Mitose , Mutação/genética , Especificidade de Órgãos , Proteína Tumoral 1 Controlada por Tradução
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