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1.
PLoS One ; 19(5): e0303371, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38728352

RESUMO

Marek's disease (MD) is an important neoplastic disease caused by serotype 1 Marek's disease virus (MDV-1), which results in severe economic losses worldwide. Despite vaccination practices that have controlled the MD epidemic, current increasing MD-suspected cases indicate the persistent viral infections circulating among vaccinated chicken farms in many countries. However, the lack of available information about phylogeny and molecular characterization of circulating MDV-1 field strains in Taiwan reveals a potential risk in MD outbreaks. This study investigated the genetic characteristics of 18 MDV-1 strains obtained from 17 vaccinated chicken flocks in Taiwan between 2018 and 2020. Based on the sequences of the meq oncogene, the phylogenetic analysis demonstrated that the circulating Taiwanese MDV-1 field strains were predominantly in a single cluster that showed high similarity with strains from countries of the East Asian region. Because the strains were obtained from CVI988/Rispens vaccinated chicken flocks and the molecular characteristics of the Meq oncoprotein showed features like vvMDV and vv+MDV strains, the circulating Taiwanese MDV-1 field strains may have higher virulence compared with vvMDV pathotype. In conclusion, the data presented demonstrates the circulation of hypervirulent MDV-1 strains in Taiwan and highlights the importance of routine surveillance and precaution strategies in response to the emergence of enhanced virulent MDV-1.


Assuntos
Galinhas , Herpesvirus Galináceo 2 , Doença de Marek , Proteínas Oncogênicas Virais , Animais , Galinhas/virologia , Herpesvirus Galináceo 2/classificação , Herpesvirus Galináceo 2/genética , Herpesvirus Galináceo 2/patogenicidade , Doença de Marek/virologia , Doença de Marek/prevenção & controle , Vacinas contra Doença de Marek/genética , Vacinas contra Doença de Marek/imunologia , Proteínas Oncogênicas Virais/genética , Filogenia , Doenças das Aves Domésticas/virologia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/prevenção & controle , Taiwan/epidemiologia , Vacinação/veterinária , Virulência/genética
2.
Biomed Opt Express ; 15(3): 1739-1749, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38495710

RESUMO

Quantifying hemoglobin is vital yet invasive through blood draws. We developed a wearable diffuse reflectance spectroscopy device comprising control and sensor boards with photodiodes and light-emitting diodes to noninvasively determine hemoglobin. Neural networks enabled recovery of optical parameters for chromophore fitting to calculate hemoglobin. Testing healthy and elderly subjects revealed strong correlation (r=0.9) between our system and invasive methods after data conversion. Bland-Altman analysis demonstrated tight 95% limits of agreement from -1.98 to 1.98 g/dL between the DRS and invasive hemoglobin concentrations. By spectroscopically isolating hemoglobin absorption, interference from melanin was overcome. Our device has the potential for future integration into wearable technology, enabling hemoglobin level tracking.

3.
PLoS Genet ; 19(12): e1011102, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38117861

RESUMO

Acute lymphoblastic leukemia/lymphoma (ALL) is the most common pediatric cancer and is a malignancy of T or B lineage lymphoblasts. Dysregulation of intracellular Ca2+ levels has been observed in patients with ALL, leading to improper activation of downstream signaling. Here we describe a new zebrafish model of B ALL, generated by expressing human constitutively active CaMKII (CA-CaMKII) in tp53 mutant lymphocytes. In this model, B cell hyperplasia in the kidney marrow and spleen progresses to overt leukemia/lymphoma, with only 29% of zebrafish surviving the first year of life. Leukemic fish have reduced productive genomic VDJ recombination in addition to reduced expression and improper splicing of ikaros1, a gene often deleted or mutated in patients with B ALL. Inhibiting CaMKII in human pre-B ALL cells induced cell death, further supporting a role for CaMKII in leukemogenesis. This research provides novel insight into the role of Ca2+-directed signaling in lymphoid malignancy and will be useful in understanding disease development and progression.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Animais , Humanos , Peixe-Zebra/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Cálcio , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia
4.
Genes Chromosomes Cancer ; 61(8): 491-496, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35294081

RESUMO

Non-Down-syndrome-related acute megakaryoblastic leukemia (non-DS-AMKL) is a rare form of leukemia that can present with a variety of initial symptoms, including fever, rash, bruising, bleeding, or other more clinically challenging symptoms. Herein, we describe a 19-month-old female patient who presented with left lower extremity pain and language regression who was diagnosed with AMKL, not otherwise specified (NOS), on the basis of peripheral blood and bone marrow analysis, as well as cytogenetic and molecular diagnostic phenotyping. Of note, in addition to this patient's karyotype showing trisomy 3, a fusion between CBFA2T3 (core-binding factor, alpha subunit 2, translocated to, 3) on chromosome 16 and GLIS2 (GLIS family zinc finger protein 2), also on chromosome 16, was observed. Patients with AMKL who have trisomy 3 with CBFA2T3::GLIS2 fusions are rare, and it is not known if the co-occurrence of these abnormalities is coincidental or biologically related. This highlights the continued need for further expansion of genetic testing in individuals with rare disease to establish the groundwork for identifying additional commonalities that could potentially be used to identify therapeutic targets or improve prognostication.


Assuntos
Leucemia Megacarioblástica Aguda , Criança , Feminino , Humanos , Lactente , Cariótipo , Leucemia Megacarioblástica Aguda/diagnóstico , Leucemia Megacarioblástica Aguda/genética , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Proteínas Repressoras/genética , Trissomia/genética
5.
Cells ; 10(2)2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33494295

RESUMO

The disease progression of nonalcoholic fatty liver disease (NAFLD) from simple steatosis (NAFL) to nonalcoholic steatohepatitis (NASH) is driven by multiple factors. Berberine (BBR) is an ancient Chinese medicine and has various beneficial effects on metabolic diseases, including NAFLD/NASH. However, the underlying mechanisms remain incompletely understood due to the limitation of the NASH animal models used. Methods: A high-fat and high-fructose diet-induced mouse model of NAFLD, the best available preclinical NASH mouse model, was used. RNAseq, histological, and metabolic pathway analyses were used to identify the potential signaling pathways modulated by BBR. LC-MS was used to measure bile acid levels in the serum and liver. The real-time RT-PCR and Western blot analysis were used to validate the RNAseq data. Results: BBR not only significantly reduced hepatic lipid accumulation by modulating fatty acid synthesis and metabolism but also restored the bile acid homeostasis by targeting multiple pathways. In addition, BBR markedly inhibited inflammation by reducing immune cell infiltration and inhibition of neutrophil activation and inflammatory gene expression. Furthermore, BBR was able to inhibit hepatic fibrosis by modulating the expression of multiple genes involved in hepatic stellate cell activation and cholangiocyte proliferation. Consistent with our previous findings, BBR's beneficial effects are linked with the downregulation of microRNA34a and long noncoding RNA H19, which are two important players in promoting NASH progression and liver fibrosis. Conclusion: BBR is a promising therapeutic agent for NASH by targeting multiple pathways. These results provide a strong foundation for a future clinical investigation.


Assuntos
Berberina/uso terapêutico , Progressão da Doença , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Transdução de Sinais , Animais , Berberina/farmacologia , Ácidos e Sais Biliares/metabolismo , Dieta Ocidental , Ácidos Graxos/metabolismo , Perfilação da Expressão Gênica , Ontologia Genética , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Camundongos Endogâmicos C57BL , Modelos Biológicos , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/genética , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Transdução de Sinais/efeitos dos fármacos , Transcriptoma/genética
7.
Pathogens ; 8(3)2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31500305

RESUMO

Chicken infectious anemia caused by chicken anemia virus (CAV) is a very important immunosuppressive disease in chickens. The horizontal spread of CAV in field chickens has been confirmed mainly through oral infection in our published article. Anemia is the main symptom of this disease. Studies by other scientists have shown that infection of CAV in 1-day-old chicks can cause anemia, and the degree of anemia is directly proportional to the dose of infectious virus. However, the pathogenesis of oral inoculation of CAV in older chickens is still not well understood. The purpose of this study was to determine whether 3-weeks-old specific-pathogen-free (SPF) chickens infected with different viral doses in oral route would cause anemia, as well as other signs associated with age-resistance. The experimental design was divided into a high-dose inoculated group (106 1050), low-dose inoculated group (103 TCID50), and non-virus inoculated control group, and 12 birds in each group at the beginning of the trial. The packed cell volumes (PCVs), CAV genome copies in tissues, CAV titer in peripheral blood fractions, and serology were evaluated at 7, 14, and 21 days post-infection (dpi). Virus replication and spread were estimated using quantitative polymerase chain reaction (qPCR) and viral titration in cell culture, respectively. The results showed that the average PCVs value of the high-dose inoculated group was significantly lower than that of the control group at 14 dpi (p < 0.05), and 44.4% (4/9) of the chickens reached the anemia level (PCVs < 27%). At 21 dpi, the average PCV value rebounded but remained lower than the control group without significant differences. In the low-dose inoculated group, all birds did not reach anemia during the entire trial period. Peripheral blood analysis showed that the virus titer in all erythrocyte, granulocyte and mononuclear cell reached the peak at 14 dpi regardless of the high-dose or low-dose inoculated group, and the highest virus titer appeared in the high-dose inoculated group of mononuclear cell. In the low-dose inoculated group, CAV was detected only at 14 dpi in erythrocyte. Taken together, our results indicate that the older birds require a higher dose of infectious CAV to cause anemia after about 14 days of infection, which is related to apoptosis caused by viral infection of erythrocytes. In both inoculated groups, the viral genome copies did not increase in the bone marrow, which indicated that minimal cell susceptibility to CAV was found in older chickens. In the low-dose inoculated group, only mononuclear cells can still be detected with CAV at 21 dpi in seropositive chickens, indicating that the mononuclear cell is the target cell for persistent infection. Therefore, complete elimination of the CAV may still require the aid of a cell-mediated immune response (CMI), although it has previously been reported to be inhibited by CAV infection. Prevention of early exposure to CAV could be possible by improved hygiene procedures.

8.
Case Rep Hematol ; 2019: 5315086, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31346479

RESUMO

Hepatosplenic T-cell lymphomas (TCLs) are a rare, aggressive subset of TCLs, accounting for less than 5% of all peripheral T-cell and natural killer (NK) cell lymphomas. We report the case of a CD3 negative hepatosplenic T-cell lymphoma in a 42-year-old female, who presented with left-sided abdominal pain. She underwent a liver biopsy that showed marked abnormal sinusoidal lymphoid infiltration. PET scan revealed increased splenic and pharyngeal lymph node uptake. Immunophenotype was remarkable for negative CD3, gamma delta T-cell receptor, and alpha beta-T-cell receptor expression. She received 6 cycles of DA-EPOCH, had primary refractory disease and then underwent palliative splenectomy secondary to painful necrosis. Then, she was started on pralatrexate as a single agent and then in combination with romidepsin as a potential bridge to an allogeneic stem cell transplantation from her sibling.

9.
Virol J ; 16(1): 45, 2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30953524

RESUMO

BACKGROUND: VP1 of the chicken anemia virus (CAV) is a structural protein that is required for virus encapsulation. VP1 proteins are present both in the nucleus and cytoplasm; however, the functional nuclear localization signal (NLS) and nuclear export signal (NES) of VP1 are still unknown. This study aimed to characterize the NLS and NES motifs of VP1 using bioinformatics methods and multiple-site fragment deletions, and investigate shuttling of VP2 from nucleus to cytoplasm by co-transfection with VP1. METHODS: Two putative NLS motifs were predicted by the WoLF PSORT and NLStradamus programs from the amino acid sequence of VP1. Three NES motifs of VP1 were predicted by the NetNES 1.1 Server and ELM server programs. All mutants were created by multiple-site fragment deletion mutagenesis. VP1 and VP2 were co-expressed in cells using plasmid transfection. RESULTS: A functional NLS motif was identified at amino acid residues 3 to 10 (RRARRPRG) of VP1. Critical amino acids 3 to 10 were significantly involved in nuclear import in cells and were evaluated using systematic deletion mutagenesis. Three NES motifs of VP1 were predicted by the NetNES 1.1 Server and ELM server programs. A functional NES was identified at amino acid residues 375 to 388 (ELDTNFFTLYVAQ). Leptomycin B (LMB) treatment demonstrated that VP1 export from nucleus to cytoplasm occurred through a chromosome region maintenance 1 (CRM1)-dependent pathway. With co-expression of VP1 and VP2 in cells, we observed that VP1 may transport VP2 from nucleus to cytoplasm. CONCLUSION: Our data showed that VP1 of CAV contained functional NLS and NES motifs that modulated nuclear import and export through a CRM1-dependent pathway. Further, VP1 may play a role in the transport of VP2 from nucleus to cytoplasm.


Assuntos
Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Vírus da Anemia da Galinha/genética , Sinais de Exportação Nuclear , Sinais de Localização Nuclear/genética , Transporte Ativo do Núcleo Celular , Motivos de Aminoácidos , Animais , Células CHO , Núcleo Celular/metabolismo , Vírus da Anemia da Galinha/efeitos dos fármacos , Biologia Computacional , Cricetulus , Citoplasma/metabolismo , Ácidos Graxos Insaturados/farmacologia , Carioferinas/metabolismo , Mutagênese , Sinais de Localização Nuclear/química , Ligação Proteica , Transporte Proteico , Receptores Citoplasmáticos e Nucleares/metabolismo , Transfecção , Proteína Exportina 1
10.
Hepatology ; 70(4): 1317-1335, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30985008

RESUMO

Activation of hepatic stellate cells (HSCs) represents the primary driving force to promote the progression of chronic cholestatic liver diseases. We previously reported that cholangiocyte-derived exosomal long noncoding RNA-H19 (lncRNA-H19) plays a critical role in promoting cholestatic liver injury. However, it remains unclear whether cholangiocyte-derived lncRNA-H19 regulates HSC activation, which is the major focus of this study. Both bile duct ligation (BDL) and Mdr2 knockout (Mdr2-/- ) mouse models were used. Wild-type and H19maternalΔExon1/+ (H19KO) mice were subjected to BDL. Mdr2-/- H19maternalΔExon1/+ (DKO) mice were generated. Exosomes isolated from cultured mouse and human cholangiocytes or mouse serum were used for in vivo transplantation and in vitro studies. Fluorescence-labeled exosomes and flow cytometry were used to monitor exosome uptake by hepatic cells. Collagen gel contraction and bromodeoxyuridine assays were used to determine the effect of exosomal-H19 on HSC activation and proliferation. Mouse and human primary sclerosing cholangitis (PSC)/primary biliary cholangitis (PBC) liver samples were analyzed by real-time PCR, western blot analysis, histology, and immunohistochemistry. The results demonstrated that hepatic H19 level was closely correlated with the severity of liver fibrosis in both mouse models and human patients with PSC and PBC. H19 deficiency significantly protected mice from liver fibrosis in BDL and Mdr2-/- mice. Transplanted cholangiocyte-derived H19-enriched exosomes were rapidly and preferentially taken up by HSCs and HSC-derived fibroblasts, and promoted liver fibrosis in BDL-H19KO mice and DKO mice. H19-enriched exosomes enhanced transdifferentiation of cultured mouse primary HSCs and promoted proliferation and matrix formation in HSC-derived fibroblasts. Conclusion: Cholangiocyte-derived exosomal H19 plays a critical role in the progression of cholestatic liver fibrosis by promoting HSC differentiation and activation and represents a potential diagnostic biomarker and therapeutic target for cholangiopathies.


Assuntos
Colangite Esclerosante/genética , Colestase/patologia , Exossomos/genética , Regulação da Expressão Gênica , Cirrose Hepática/genética , RNA Longo não Codificante/genética , Animais , Proliferação de Células/genética , Células Cultivadas , Colangite Esclerosante/patologia , Colestase/genética , Modelos Animais de Doenças , Citometria de Fluxo , Células Estreladas do Fígado/patologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Knockout , Distribuição Aleatória , Especificidade da Espécie
11.
Dig Liver Dis ; 51(8): 1154-1163, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31003959

RESUMO

Alcoholic liver disease (ALD) is one of the most common liver diseases worldwide. However, the exact mechanisms underlying ALD remain unclear. Previous studies reported that sphingosine kinase 2 (SphK2) plays an essential role in regulating hepatic lipid metabolism. In the current study, we demonstrate that compared to wild-type (WT) mice, SphK2 deficient (SphK2-/-) mice exhibited a greater degree of liver injury and hepatic lipid accumulation after feeding with an alcohol diet for 60 days. This is accompanied by a down-regulation of steroid 7-alpha-hydroxylase (Cyp7b1) and an up-regulation of pro-inflammatory mediators (Tnfα, F4/80, Il-1ß). In vitro experiments showed that alcohol induced SphK2 expression in mouse primary hepatocytes and cultured mouse macrophages. Furthermore, alcohol feeding induced a more severe intestinal barrier dysfunction in SphK2-/- mice than WT mice. Deficiency of SphK2 impaired the growth of intestinal organoids. Finally, SphK2 expression levels were down-regulated in the livers of human patients with alcoholic cirrhosis and hepatocellular carcinoma compared to healthy controls. In summary, these findings suggest that SphK2 is a crucial regulator of hepatic lipid metabolism and that modulating the SphK2-mediated signaling pathway may represent a novel therapeutic strategy for the treatment of ALD and other metabolic liver diseases.


Assuntos
Hepatopatias Alcoólicas/enzimologia , Fígado/enzimologia , Fígado/patologia , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Animais , Células Cultivadas , Feminino , Hepatócitos/enzimologia , Humanos , Intestinos/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais , Esteroide Hidroxilases/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
12.
BMC Vet Res ; 14(1): 155, 2018 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-29728113

RESUMO

BACKGROUND: Chicken anaemia virus (CAV) is commonly found in poultry. VP1 is the sole structural protein of CAV, which is the major component responsible for capsid assembly. The CAV virion consists of the VP1 protein and a viral genome. However, there is currently no information on the protein-nucleic acid interactions between VP1 and DNA molecules. RESULTS: In this study, the recombinant VP1 protein of CAV was expressed and purified to characterize its DNA binding activity. When VP1 protein was incubated with a DNA molecule, the DNA molecule exhibited retarded migration on an agarose gel. Regardless of whether the sequence of the viral genome was involved in the DNA molecule, DNA retardation was not significantly influenced. This outcome indicated VP1 is a DNA binding protein with no sequence specificity. Various DNA molecules with different conformations, such as circular dsDNA, linear dsDNA, linear ssDNA and circular ssDNA, interacted with VP1 proteins according to the results of a DNA retardation assay. Further quantification of the amount of VP1 protein required for DNA binding, the circular ssDNA demonstrated a high affinity for the VP1 protein. The preferences arranged in the order of affinity for the VP1 protein with DNA are circular ssDNA, linear ssDNA, supercoiled circular dsDNA, open circular DNA and linear dsDNA. CONCLUSIONS: The results of this study demonstrated that the interaction between VP1 and DNA molecules exhibited various binding preferences that were dependent on the structural conformation of DNA. Taken together, the results of this report are the first to demonstrate that VP1 has no sequence-specific DNA binding activity. The particular binding preferences of VP1 might play multiple roles in DNA replication or encapsidation during the viral life cycle.


Assuntos
Proteínas do Capsídeo/metabolismo , Vírus da Anemia da Galinha/metabolismo , DNA Viral/metabolismo , Proteínas de Ligação a DNA/metabolismo , Vírus da Anemia da Galinha/genética , Proteínas de Ligação a DNA/genética , Ligação Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
13.
Hepatology ; 68(2): 599-615, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29425397

RESUMO

Cholestatic liver injury is an important clinical problem with limited understanding of disease pathologies. Exosomes are small extracellular vesicles released by a variety of cells, including cholangiocytes. Exosome-mediated cell-cell communication can modulate various cellular functions by transferring a variety of intracellular components to target cells. Our recent studies indicate that the long noncoding RNA (lncRNA), H19, is mainly expressed in cholangiocytes, and its aberrant expression is associated with significant down-regulation of small heterodimer partner (SHP) in hepatocytes and cholestatic liver injury in multidrug resistance 2 knockout (Mdr2-/- ) mice. However, how cholangiocyte-derived H19 suppresses SHP in hepatocytes remains unknown. Here, we report that cholangiocyte-derived exosomes mediate transfer of H19 into hepatocytes and promote cholestatic injury. Hepatic H19 level is correlated with severity of cholestatic injury in both fibrotic mouse models, including Mdr2-/- mice, a well-characterized model of primary sclerosing cholangitis (PSC), or CCl4 -induced cholestatic liver injury mouse models, and human PSC patients. Moreover, serum exosomal-H19 level is gradually up-regulated during disease progression in Mdr2-/- mice and patients with cirrhosis. H19-carrying exosomes from the primary cholangiocytes of wild-type (WT) mice suppress SHP expression in hepatocytes, but not the exosomes from the cholangiocytes of H19-/- mice. Furthermore, overexpression of H19 significantly suppressed SHP expression at both transcriptional and posttranscriptional levels. Importantly, transplant of H19-carrying serum exosomes of old fibrotic Mdr2-/- mice significantly promoted liver fibrosis (LF) in young Mdr2-/- mice. CONCLUSION: Cholangiocyte-derived exosomal-H19 plays a critical role in cholestatic liver injury. Serum exosomal H19 represents a noninvasive biomarker and potential therapeutic target for cholestatic diseases. (Hepatology 2018).


Assuntos
Ductos Biliares/patologia , Colestase/genética , Fígado/patologia , RNA Longo não Codificante/metabolismo , Animais , Ductos Biliares/metabolismo , Colangite Esclerosante/patologia , Colestase/patologia , Exossomos/genética , Feminino , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Knockout , Receptores Citoplasmáticos e Nucleares/metabolismo
14.
Hepatology ; 67(4): 1441-1457, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28926118

RESUMO

Impaired intestinal barrier function promotes the progression of various liver diseases, including cholestatic liver diseases. The close association of primary sclerosing cholangitis (PSC) with inflammatory bowel disease highlights the importance of the gut-liver axis. It has been reported that bile duct ligation (BDL)-induced liver fibrosis is significantly reduced in C/EBP homologous protein knockout (CHOP-/- ) mice. However, the underlying mechanisms remain unclear. In the current study, we demonstrate that BDL induces striking and acute hepatic endoplasmic reticulum (ER) stress responses after 1 day, which return to normal after 3 days. No significant hepatocyte apoptosis is detected 7-14 days following BDL. However, the inflammatory response is significantly increased after 7 days, which is similar to what we found in human PSC liver samples. BDL-induced loss of stemness in intestinal stem cells (ISCs), disruption of intestinal barrier function, bacterial translocation, activation of hepatic inflammation, M2 macrophage polarization and liver fibrosis are significantly reduced in CHOP-/- mice. In addition, intestinal organoids derived from CHOP-/- mice contain more and longer crypt structures than those from wild-type (WT) mice, which is consistent with the upregulation of stem cell markers (leucine-rich repeat-containing G-protein-coupled receptor 5, olfactomedin 4, and SRY [sex determining region Y]-box 9) and in vivo findings that CHOP-/- mice have longer villi and crypts as compared to WT mice. Similarly, mRNA levels of CD14, interleukin-1ß, tumor necrosis factor-alpha, and monocyte chemotactic protein-1 are increased and stem cell proliferation is suppressed in the duodenum of patients with cirrhosis. CONCLUSION: Activation of ER stress and subsequent loss of stemness of ISCs plays a critical role in BDL-induced systemic inflammation and cholestatic liver injury. Modulation of the ER stress response represents a potential therapeutic strategy for cholestatic liver diseases as well as other inflammatory diseases. (Hepatology 2018;67:1441-1457).


Assuntos
Ductos Biliares/patologia , Colestase/patologia , Mucosa Intestinal/patologia , Células-Tronco/metabolismo , Fator de Transcrição CHOP/metabolismo , Animais , Apoptose/genética , Técnicas de Cultura de Células , Estresse do Retículo Endoplasmático/genética , Feminino , Hepatócitos/patologia , Humanos , Ligadura/efeitos adversos , Fígado/patologia , Hepatopatias/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco/fisiologia , Fator de Transcrição CHOP/genética
15.
Sci Rep ; 7(1): 14799, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29093508

RESUMO

Chicken anaemia virus (CAV) is an important contagious agent that causes immunosuppressive disease in chickens. CAV Apoptin is a nucleoplasmic shuffling protein that induces apoptosis in chicken lymphoblastoid cells. In the present study, confocal microscopy revealed co-localisation of expressed CAV non-structural protein VP2 with Apoptin in the nucleus of MDCC-MSB1 cells and the nucleoplasmic compartment of CHO-K1 cells. In vitro pull-down and ex vivo biomolecular fluorescent complementation (BiFC) assays further showed that the VP2 protein directly interacts with Apoptin. Transient co-expression of VP2 and Apoptin in MDCC-MSB1 cells significantly decreased the rate of apoptosis compared with that in cells transfected with the Apoptin gene alone. In addition, the phosphorylation status of threonine 108 (Thr108) of Apoptin was found to decrease upon interaction with VP2. Although dephosphorylated Thr108 did not alter the subcellular distribution of Apoptin in the nucleus of MDCC-MSB1 cells, it did suppress apoptosis. These findings provide the first evidence that VP2 directly interacts with Apoptin in the nucleus to down-regulate apoptosis through alterations in the phosphorylation status of the latter. This information will be useful to further elucidate the underlying mechanism of viral replication in the CAV life cycle.


Assuntos
Apoptose , Proteínas do Capsídeo/metabolismo , Vírus da Anemia da Galinha/fisiologia , Regulação para Baixo , Regulação Viral da Expressão Gênica , Replicação Viral , Animais , Células CHO , Proteínas do Capsídeo/genética , Galinhas , Cricetulus , Fosforilação , Treonina
16.
Hepatology ; 66(3): 869-884, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28271527

RESUMO

The multidrug resistance 2 knockout (Mdr2-/- ) mouse is a well-established model of cholestatic cholangiopathies. Female Mdr2-/- mice develop more severe hepatobiliary damage than male Mdr2-/- mice, which is correlated with a higher proportion of taurocholate in the bile. Although estrogen has been identified as an important player in intrahepatic cholestasis, the underlying molecular mechanisms of gender-based disparity of cholestatic injury remain unclear. The long noncoding RNA H19 is an imprinted, maternally expressed, and estrogen-targeted gene, which is significantly induced in human fibrotic/cirrhotic liver and bile duct-ligated mouse liver. However, whether aberrant expression of H19 accounts for gender-based disparity of cholestatic injury in Mdr2-/- mice remains unknown. The current study demonstrated that H19 was markedly induced (∼200-fold) in the livers of female Mdr2-/- mice at advanced stages of cholestasis (100 days old) but not in age-matched male Mdr2-/- mice. During the early stages of cholestasis, H19 expression was minimal. We further determined that hepatic H19 was mainly expressed in cholangiocytes, not hepatocytes. Both taurocholate and estrogen significantly activated the extracellular signal-regulated kinase 1/2 signaling pathway and induced H19 expression in cholangiocytes. Knocking down H19 not only significantly reduced taurocholate/estrogen-induced expression of fibrotic genes and sphingosine 1-phosphate receptor 2 in cholangiocytes but also markedly reduced cholestatic injury in female Mdr2-/- mice. Furthermore, expression of small heterodimer partner was substantially inhibited at advanced stages of liver fibrosis, which was reversed by H19 short hairpin RNA in female Mdr2-/- mice. Similar findings were obtained in human primary sclerosing cholangitis liver samples. CONCLUSION: H19 plays a critical role in the disease progression of cholestasis and represents a key factor that causes the gender disparity of cholestatic liver injury in Mdr2-/- mice. (Hepatology 2017;66:869-884).


Assuntos
Colangite Esclerosante/patologia , Colestase/patologia , Regulação da Expressão Gênica , RNA Longo não Codificante/genética , Receptores de Lisoesfingolipídeo/genética , Animais , Colangite Esclerosante/genética , Colestase/genética , Modelos Animais de Doenças , Regulação para Baixo , Estrogênios/farmacologia , Feminino , Técnicas de Inativação de Genes , Genes MDR , Humanos , Cirrose Hepática/genética , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Knockout , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Papel (figurativo) , Fatores Sexuais , Receptores de Esfingosina-1-Fosfato , Ácido Taurocólico/farmacologia
17.
Hepatology ; 65(6): 2005-2018, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28120434

RESUMO

Bile duct obstruction is a potent stimulus for cholangiocyte proliferation, especially for large cholangiocytes. Our previous studies reported that conjugated bile acids (CBAs) activate the protein kinase B (AKT) and extracellular signal-regulated kinase 1 and 2 (ERK1/2) signaling pathways through sphingosine 1-phosphate receptor (S1PR) 2 in hepatocytes and cholangiocarcinoma cells. It also has been reported that taurocholate (TCA) promotes large cholangiocyte proliferation and protects cholangiocytes from bile duct ligation (BDL)-induced apoptosis. However, the role of S1PR2 in bile-acid-mediated cholangiocyte proliferation and cholestatic liver injury has not been elucidated. Here, we report that S1PR2 is the predominant S1PR expressed in cholangiocytes. Both TCA- and sphingosine-1-phosphate (S1P)-induced activation of ERK1/2 and AKT were inhibited by JTE-013, a specific antagonist of S1PR2, in cholangiocytes. In addition, TCA- and S1P-induced cell proliferation and migration were inhibited by JTE-013 and a specific short hairpin RNA of S1PR2, as well as chemical inhibitors of ERK1/2 and AKT in mouse cholangiocytes. In BDL mice, expression of S1PR2 was up-regulated in whole liver and cholangiocytes. S1PR2 deficiency significantly reduced BDL-induced cholangiocyte proliferation and cholestatic injury, as indicated by significant reductions in inflammation and liver fibrosis in S1PR2 knockout mice. Treatment of BDL mice with JTE-013 significantly reduced total bile acid levels in serum and cholestatic liver injury. CONCLUSION: This study suggests that CBA-induced activation of S1PR2-mediated signaling pathways plays a critical role in obstructive cholestasis and may represent a novel therapeutic target for cholestatic liver diseases. (Hepatology 2017;65:2005-2018).


Assuntos
Colangiocarcinoma/patologia , Colangite Esclerosante/patologia , Colestase/patologia , Cirrose Hepática/patologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Receptores de Lisoesfingolipídeo/metabolismo , Análise de Variância , Animais , Ácidos e Sais Biliares/farmacologia , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares/cirurgia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Colangiocarcinoma/metabolismo , Colangite Esclerosante/metabolismo , Colestase/complicações , Modelos Animais de Doenças , Ligadura , Fígado/lesões , Fígado/patologia , Cirrose Hepática/metabolismo , Lisofosfolipídeos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos CBA , Camundongos Knockout , Distribuição Aleatória , Papel (figurativo) , Transdução de Sinais , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Receptores de Esfingosina-1-Fosfato , Regulação para Cima
19.
J Environ Manage ; 160: 263-70, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26144562

RESUMO

In this study, loop-mediated isothermal amplification (LAMP) and real-time LAMP assays were developed to detect the dioxin-degrading bacterium Ochrobactrum anthropi strain BD-1 in soil. Four primers were designed to use ITS gene amplification for the strain O. anthropi BD-1. The real-time LAMP assay was found to accomplish the reaction by 1 pg of genomic DNA load when used for nucleic acid amplification. This assay was then applied to detect O. anthropi BD-1 in eight soil samples collected from a dioxin-contaminated site. The results demonstrated that these newly developed LAMP and real-time LAMP assays will not only be useful and efficient tools for detecting the target gene, but also be used as molecular tools for monitoring the growth of dioxin-degrading O. anthropi in the soil. This is the first report to demonstrate the use of LAMP assays to monitor the presence of O. anthropi in dioxin-contaminated soil. The application of this method should improve the biomonitoring of dioxin contamination.


Assuntos
Dioxinas/química , Técnicas de Amplificação de Ácido Nucleico/métodos , Ochrobactrum anthropi/genética , Microbiologia do Solo , Primers do DNA , DNA Bacteriano/análise , Humanos , Reprodutibilidade dos Testes
20.
Int J Mol Sci ; 16(1): 1562-75, 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25584616

RESUMO

Taraxacum formosanum (TF) is a medicinal plant used as an important component of health drinks in Taiwan. In this study, a rapid, sensitive and specific loop-mediated isothermal amplification (LAMP) assay for authenticating TF was established. A set of four specific LAMP primers was designed based on the nucleotide sequence of the internal transcribed spacer 2 (ITS2) nuclear ribosomal DNA (nrDNA) of TF. LAMP amplicons were successfully amplified and detected when purified genomic DNA of TF was added in the LAMP reaction under isothermal condition (65 °C) within 45 min. These specific LAMP primers have high specificity and can accurately discriminate Taraxacum formosanum from other adulterant plants; 1 pg of genomic DNA was determined to be the detection limit of the LAMP assay. In conclusion, using this novel approach, TF and its misused plant samples obtained from herbal tea markets were easily identified and discriminated by LAMP assay for quality control.


Assuntos
Genes de Plantas , Taraxacum/metabolismo , Sequência de Bases , Primers do DNA/metabolismo , DNA Ribossômico/genética , DNA Ribossômico/metabolismo , Análise Discriminante , Dados de Sequência Molecular , Técnicas de Amplificação de Ácido Nucleico , Alinhamento de Sequência , Temperatura
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