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1.
FASEB J ; 36(9): e22452, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35916017

RESUMO

House dust mite (HDM) allergens cause inflammatory responses and chronic allergic diseases such as bronchial asthma and atopic dermatitis. Here, we investigate the mechanism by which HDM induces C-C chemokine ligand 20 (CCL20) expression to promote chronic inflammation and airway remodeling in an HDM-induced bronchial asthma mouse model. We showed that HDM increased CCL20 levels via the Akt-ERK1/2-C/EBPß pathway. To investigate the role of CCL20 in chronic airway inflammation and remodeling, we made a mouse model of CCL20-induced bronchial asthma. Treatment of anti-CCL20Ab in this mouse model showed the reduced airway hyper-responsiveness and inflammatory cell infiltration into peribronchial region by neutralizing CCL20. In addition, CCL20 induced the Nod-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome activation through NLRP3 deubiquitination and transcriptional upregulation in BEAS-2B cells. As expected, anti-CCL20Ab markedly suppressed NLRP3 activation induced by CCL20. Moreover, HDM-induced CCL20 leads to epithelial-mesenchymal transition in the lung epithelium which appears to be an important regulator of airway remodeling in allergic asthma. We also found that anti-CCL20Ab attenuates airway inflammation and remodeling in an HDM-induced mouse model of bronchial asthma. Taken together, our results suggest that HDM-induced CCL20 is required for chronic inflammation that contributes airway remodeling in a mouse model of asthma.


Assuntos
Asma , Pyroglyphidae , Remodelação das Vias Aéreas , Animais , Asma/metabolismo , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal , Inflamação/complicações , Ligantes , Pulmão/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
2.
Hepatology ; 73(4): 1307-1326, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32557804

RESUMO

BACKGROUND AND AIMS: Fat accumulation results from increased fat absorption and/or defective fat metabolism. Currently, the lipid-sensing nuclear receptor that controls fat utilization in hepatocytes is elusive. Liver X receptor alpha (LXRα) promotes accumulation of lipids through the induction of several lipogenic genes. However, its effect on lipid degradation is open for study. Here, we investigated the inhibitory role of LXRα in autophagy/lipophagy in hepatocytes and the underlying basis. APPROACH AND RESULTS: In LXRα knockout mice fed a high-fat diet, or cell models, LXRα activation suppressed the function of mitochondria by inhibiting autophagy/lipophagy and induced hepatic steatosis. Gene sets associated with "autophagy" were enriched in hepatic transcriptome data. Autophagy flux was markedly augmented in the LXRα knockout mouse liver and primary hepatocytes. Mechanistically, LXRα suppressed autophagy-related 4B cysteine peptidase (ATG4B) and Rab-8B, responsible for autophagosome and -lysosome formation, by inducing let-7a and microRNA (miR)-34a. Chromatin immunoprecipitation assay enabled us to find LXRα as a transcription factor of let-7a and miR-34a. Moreover, 3' untranslated region luciferase assay substantiated the direct inhibitory effects of let-7a and miR-34a on ATG4B and Rab-8B. Consistently, either LXRα activation or the let-7a/miR-34a transfection lowered mitochondrial oxygen consumption rate and mitochondrial transmembrane potential and increased fat levels. In obese animals or nonalcoholic fatty liver disease (NAFLD) patients, let-7a and miR-34a levels were elevated with simultaneous decreases in ATG4B and Rab-8B levels. CONCLUSIONS: LXRα inhibits autophagy in hepatocytes through down-regulating ATG4B and Rab-8B by transcriptionally activating microRNA let-7a-2 and microRNA 34a genes and suppresses mitochondrial biogenesis and fuel consumption. This highlights a function of LXRα that culminates in the progression of liver steatosis and steatohepatitis, and the identified targets may be applied for a therapeutic strategy in the treatment of NAFLD.


Assuntos
Proteínas Relacionadas à Autofagia/metabolismo , Autofagia/fisiologia , Cisteína Endopeptidases/metabolismo , Hepatócitos/metabolismo , Receptores X do Fígado/metabolismo , Mitocôndrias/fisiologia , Proteínas rab de Ligação ao GTP/metabolismo , Ativação Metabólica , Animais , Autofagia/genética , Proteínas Relacionadas à Autofagia/genética , Cisteína Endopeptidases/genética , Modelos Animais de Doenças , Progressão da Doença , Regulação para Baixo , Fígado Gorduroso/etiologia , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Fígado Gorduroso/fisiopatologia , Células Hep G2/metabolismo , Células Hep G2/fisiologia , Hepatócitos/fisiologia , Humanos , Metabolismo dos Lipídeos/genética , Metabolismo dos Lipídeos/fisiologia , Fígado/metabolismo , Fígado/fisiologia , Fígado/fisiopatologia , Receptores X do Fígado/genética , Receptores X do Fígado/fisiologia , Camundongos , Camundongos Knockout , MicroRNAs/genética , MicroRNAs/metabolismo , MicroRNAs/fisiologia , Mitocôndrias/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Biogênese de Organelas , Consumo de Oxigênio/genética , Consumo de Oxigênio/fisiologia , Transcriptoma , Proteínas rab de Ligação ao GTP/genética
3.
Lab Invest ; 101(2): 155-164, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32999430

RESUMO

Lung cancer is an aggressive disease and the leading cause of cancer-related deaths worldwide. In the past several decades, the incidence of adenocarcinoma has significantly increased, and accounts for ~40% of all lung cancer cases. In the present study, we investigated the clinicopathologic significance of microRNA-130b (miR-130b) in lung adenocarcinoma and analyzed its cancer-specific functions. RNA was extracted from formalin-fixed paraffin-embedded specimens of 146 lung adenocarcinoma cases, and miR-130b expression was analyzed using quantitative real-time polymerase chain reaction. NCI-H1650 cells were transfected with miR-130b mimic and inhibitor to determine its effects on tumor cell proliferation, migration, and invasion. The expression of miR-130b in lung adenocarcinoma tissues was classified into two groups according to the median value. High expression of miR-130b was associated with higher histological grade, advanced pathologic T stage, lymph node metastasis, and lymphovascular invasion. Moreover, survival analysis showed that high miR-130b expression was significantly associated with unfavorable prognosis. In addition, miR-130b upregulation promoted cell migration and invasion, while its downregulation resulted in decreased cell proliferation, migration, and wound healing in in vitro experiments. In conclusion, these findings suggest that miR-130b promotes tumor progression and serves as a biomarker of poor prognosis for patients with lung adenocarcinoma. Hence, targeting miR-130b may serve as a potential therapeutic strategy for lung cancer.


Assuntos
Adenocarcinoma de Pulmão/diagnóstico , Adenocarcinoma de Pulmão/metabolismo , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/mortalidade , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Humanos , Pulmão/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Oncogenes/genética , Prognóstico , Transcriptoma/genética
4.
EMBO Rep ; 20(10): e48058, 2019 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-31468695

RESUMO

Cyclin-dependent kinase 12 (CDK12) has emerged as an effective therapeutic target due to its ability to regulate DNA damage repair in human cancers, but little is known about the role of CDK12 in driving tumorigenesis. Here, we demonstrate that CDK12 promotes tumor initiation as a novel regulator of cancer stem cells (CSCs) and induces anti-HER2 therapy resistance in human breast cancer. High CDK12 expression caused by concurrent amplification of CDK12 and HER2 in breast cancer patients is associated with disease recurrence and poor survival. CDK12 induces self-renewal of breast CSCs and in vivo tumor-initiating ability, and also reduces susceptibility to trastuzumab. Furthermore, CDK12 kinase activity inhibition facilitates anticancer efficacy of trastuzumab in HER2+ tumors, and mice bearing trastuzumab-resistant HER2+ tumor show sensitivity to an inhibitor of CDK12. Mechanistically, the catalytic activity of CDK12 is required for the expression of genes involved in the activation of ErbB-PI3K-AKT or WNT-signaling cascades. These results suggest that CDK12 is a major oncogenic driver and an actionable target for HER2+ breast cancer to replace or augment current anti-HER2 therapies.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Carcinogênese/patologia , Quinases Ciclina-Dependentes/metabolismo , Resistencia a Medicamentos Antineoplásicos , Transdução de Sinais , Trastuzumab/uso terapêutico , Animais , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromossomos Humanos Par 17/genética , Quinases Ciclina-Dependentes/antagonistas & inibidores , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Substratos do Receptor de Insulina/metabolismo , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Ligação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Receptor ErbB-3/metabolismo , Trastuzumab/farmacologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Via de Sinalização Wnt
5.
J Gastroenterol Hepatol ; 36(7): 1997-2007, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33554346

RESUMO

BACKGROUND AND AIM: Stem cell treatments using scaffolds for liver disease have been well studied. However, macro-encapsulation of mesenchymal stem cells (MSCs) to minimize or inhibit stem cell homing has not been evaluated. Here, we conducted a proof-of-concept study using MSCs macro-encapsulated in poly lactic-co-glycolic acid in liver disease models. METHODS: Poly lactic-co-glycolic acid semipermeable membranes (surface pore size up to 40 µm) were used as the macro-encapsulation system. Macro-encapsulated pouches were loaded with MSCs and sealed. Each pouch was implanted in the subcutaneous region of the dorsum or interlobular space of the liver. Acute liver injury was induced using thioacetamide intraperitoneal injection thrice a week. For the chronic liver fibrosis model, thioacetamide dose was gradually increased, starting from 100 to 400 mg/kg over 16 weeks (thrice a week). RESULTS: In the acute liver injury model, the treated groups showed decreased liver inflammation and necrosis compared with the control. Hepatic fibrosis decreased in the treated group in the chronic liver fibrosis model compared with that in the control group. Encapsulated MSCs exhibited changed cell morphology and characteristics after implantation, showing increased periodic acid-Schiff staining and CYP2E1 expression. Migration and homing of MSCs into the liver was not observed. Under hypoxic conditions, macro-encapsulated MSCs secreted more growth hormones, including vascular endothelial growth factor, platelet-derived growth factor, angiopoietin-2, and placental growth factor, than monolayered MSCs in vitro. CONCLUSIONS: Macro-encapsulated MSCs attenuate hepatic inflammation and fibrosis by upregulating hypoxia-induced growth hormone secretion in liver disease models.


Assuntos
Hepatopatias , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Animais , Modelos Animais de Doenças , Feminino , Fibrose , Inflamação/patologia , Fígado/patologia , Cirrose Hepática/patologia , Cirrose Hepática/terapia , Hepatopatias/patologia , Fator de Crescimento Placentário , Tioacetamida/toxicidade , Fator A de Crescimento do Endotélio Vascular
6.
J Korean Med Sci ; 36(28): e189, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34282606

RESUMO

BACKGROUND: Cholecystitis is an important risk factor for gallbladder cancer, but the bile microbiome and its association with gallbladder disease has not been investigated fully. We aimed to analyze the bile microbiome in normal conditions, chronic cholecystitis, and gallbladder cancer, and to identify candidate bacteria that play an important role in gallbladder carcinogenesis. METHODS: We performed metagenome sequencing on bile samples of 10 healthy individuals, 10 patients with chronic cholecystitis, and 5 patients with gallbladder cancer, and compared the clinical, radiological, and pathological characteristics of the participants. RESULTS: No significant bacterial signal was identified in the normal bile. The predominant dysbiotic bacteria in both chronic cholecystitis and gallbladder cancer were those belonging to the Enterobacteriaceae family. Klebsiella increased significantly in the order of normal, chronic cholecystitis, and gallbladder cancer. Patients with chronic cholecystitis and dysbiotic microbiome patterns had larger gallstones and showed marked epithelial atypia, which are considered as precancerous conditions. CONCLUSION: We investigated the bile microbiome in normal, chronic cholecystitis, and gallbladder cancer. We suggest possible roles of Enterobacteriaceae, including Klebsiella, in gallbladder carcinogenesis. Our findings reveal a possible link between a dysbiotic bile microbiome and the development of chronic calculous cholecystitis and gallbladder cancer.


Assuntos
Bactérias/isolamento & purificação , Bile/metabolismo , Bile/microbiologia , Disbiose/microbiologia , Doenças da Vesícula Biliar/microbiologia , Neoplasias da Vesícula Biliar/microbiologia , Vesícula Biliar/microbiologia , Adulto , Bactérias/classificação , Estudos de Casos e Controles , Colecistite/microbiologia , Colecistite/patologia , Humanos , Metagenômica , Microbiota , Pessoa de Meia-Idade , Filogenia
7.
Int J Mol Sci ; 21(22)2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33182702

RESUMO

Dense granule proteins (GRAs) are essential components in Toxoplasma gondii, which are suggested to be promising serodiagnostic markers in toxoplasmosis. In this study, we investigated the function of GRA9 in host response and the associated regulatory mechanism, which were unknown. We found that GRA9 interacts with NLR family pyrin domain containing 3 (NLRP3) involved in inflammation by forming the NLRP3 inflammasome. The C-terminal of GRA9 (GRA9C) is essential for GRA9-NLRP3 interaction by disrupting the NLRP3 inflammasome through blocking the binding of apoptotic speck-containing (ASC)-NLRP3. Notably, Q200 of GRA9C is essential for the interaction of NLRP3 and blocking the conjugation of ASC. Recombinant GRA9C (rGRA9C) showed an anti-inflammatory effect and the elimination of bacteria by converting M1 to M2 macrophages. In vivo, rGRA9C increased the anti-inflammatory and bactericidal effects and subsequent anti-septic activity in CLP- and E. coli- or P. aeruginosa-induced sepsis model mice by increasing M2 polarization. Taken together, our findings defined a role of T. gondii GRA9 associated with NLRP3 in host macrophages, suggesting its potential as a new candidate therapeutic agent for sepsis.


Assuntos
Inflamassomos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Proteínas de Protozoários/imunologia , Sepse/terapia , Toxoplasma/imunologia , Animais , Antígenos de Protozoários/química , Antígenos de Protozoários/imunologia , Proteínas Adaptadoras de Sinalização CARD/imunologia , Modelos Animais de Doenças , Feminino , Interações Hospedeiro-Parasita/imunologia , Macrófagos/classificação , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/imunologia , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Sepse/imunologia , Sepse/prevenção & controle , Toxoplasma/genética , Toxoplasma/patogenicidade
8.
Molecules ; 25(7)2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32244387

RESUMO

Mycobacterium abscessus is the most difficult-to-treat nontuberculous mycobacteria because of its resistance to many antibiotics. In this study, we screened the Korea Chemical Bank library for a bioluminescent reporter assay to identify molecules capable of acting against M. abscessus. On application of the assay, rifamycin O showed excellent in vitro activity with a narrow range of the minimum inhibitory concentration required to inhibit the growth of 90% of the bacterium (MIC90 = 4.0-6.2 µM); its in vivo efficacy in the zebrafish (Danio rerio) infection model was comparable to that of rifabutin at 25 µM. Furthermore, rifamycin O did not show significant toxicity in cells and the zebrafish model. These results are the first in vivo indication that rifamycin O may be a drug candidate for treating M. abscessus infections.


Assuntos
Antibacterianos/farmacologia , Mycobacterium abscessus/efeitos dos fármacos , Rifamicinas/farmacologia , Animais , Antibacterianos/química , Humanos , Medições Luminescentes , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Rifamicinas/química , Peixe-Zebra
9.
Prostate ; 79(10): 1133-1146, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31050003

RESUMO

BACKGROUND: Trichomonas vaginalis (Tv) is the most common sexually transmitted parasite. It is detected in prostatic tissue of benign prostatic hyperplasia, prostatitis, and prostate cancer (PCa) and has been suggested to cause chronic prostatitis. Moreover, up to 20% of all cancers worldwide are associated with chronic inflammation. Here, we investigated whether inflammatory mediators produced by normal human prostate epithelial cells (RWPE-1) stimulated with Tv could promote growth and invasiveness of PCa cells. METHODS: Conditioned medium of RWPE-1 cells was prepared by stimulating them with Tv (trichomonad-conditioned medium [TCM]) and without Tv (conditioned medium [CM]). Promotion of PCa cells (PC3, DU145, and LNCaP) was assessed by wound healing, proliferation, and invasion assays. RESULTS: We observed that the production of interleukin (IL)-1ß, IL-6, CCL2, CXCL8, prostaglandin-E2 (PGE2 ), and COX2 by RWPE-1 cells was increased by stimulating them with Tv. When PCa cells were incubated with TCM, their proliferation, invasion, and migration increased. Moreover, they showed increased epithelial-mesenchymal transition (EMT)-related markers by a reduction in epithelial markers and an increase in mesenchymal markers. In vivo, xenograft tumor tissues injected with TCM also showed increased expression of cyclin D1 and proliferating cell nuclear antigen, as well as induction of EMT. Receptors and signal molecules of PCa cells increased in response to exposure to TCM, and blocking receptors (CXCR1, CXCR2, C-C chemokine receptor 2, glycoprotein 130, EP2, and EP4) reduced the proliferation of PCa cells with decreased production of cytokines (CCL2, IL-6, and CXCL8) and PGE2 , and expression of NF-κB and Snail1. CONCLUSIONS: Our results suggest that Tv infection may be one of the factors creating the supportive microenvironment to promote proliferation and invasiveness of PCa cells.


Assuntos
Proliferação de Células/fisiologia , Células Epiteliais/patologia , Invasividade Neoplásica/patologia , Neoplasias da Próstata/patologia , Prostatite/patologia , Trichomonas vaginalis , Quimiocina CCL2/metabolismo , Dinoprostona/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/parasitologia , Humanos , Inflamação/metabolismo , Inflamação/parasitologia , Inflamação/patologia , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Masculino , Próstata/metabolismo , Próstata/parasitologia , Próstata/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/parasitologia , Prostatite/metabolismo , Prostatite/parasitologia , Tricomoníase/metabolismo , Tricomoníase/patologia
10.
Prostate ; 79(4): 379-389, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30488471

RESUMO

BACKGROUND: Trichomonas vaginalis (T. vaginalis) is the most common sexually transmitted parasite. It has been detected in prostatic tissue of patients with prostatitis and reported to be associated with chronic prostatitis and benign prostatic hyperplasia as well as prostate cancer. Recently, experimental rodent models of prostatitis induced by pathogen infection have been developed. However, there have so far been no reports of prostatitis caused by T. vaginalis infection in animals. Here, we investigated whether infection with T. vaginalis via the rat urethra could cause prostatitis. METHODS: T. vaginalis was injected into prostate through urethra of rat (Wistar rats), and the rats were killed 1, 2, or 4 weeks later. The presence of T. vaginalis trophozoites in the rat prostates was examined by immunohistochemistry, and pathological changes of the prostate were observed by hematoxylin-eosin staining and evaluated by grading from 0 to 5 for inflammatory cell infiltration, acinar changes, and interstitial fibrosis. Infiltrated mast cells were observed by toluidine blue staining of rat prostate tissue. Chemokine C-C motif ligand 2 (CCL2) levels of the rat prostates were measured by ELISA. RESULTS: T. vaginalis trophozoites were observed in acini in the prostates of the injected rats. The prostate tissues had higher pathological scores, and 83% (5/6) and 100% (6/6) of the ventral and dorsolateral lobes (n = 6), respectively, were inflamed. Infiltration and degranulation of mast cells were observed at higher rates in prostate sections of the T. vaginalis-infected rats. Also, prostate tissues of the injected rats had increased CCL2 levels. CONCLUSIONS: Injection of T. vaginalis in rats caused prostatitis as revealed by pathologic changes, mast cell infiltration and increased CCL2 production. Therefore, this study provides the first evidence that T. vaginalis infection in rats causes prostatitis.


Assuntos
Prostatite/parasitologia , Tricomoníase/complicações , Trichomonas vaginalis , Animais , Quimiocina CCL2/análise , Masculino , Próstata/química , Próstata/patologia , Prostatite/patologia , Ratos , Ratos Wistar
11.
J Hepatol ; 70(1): 97-107, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30240598

RESUMO

BACKGROUND & AIMS: Currently, much effort is directed towards the development of new cell sources for clinical therapy using cell fate conversion by small molecules. Direct lineage reprogramming to a progenitor state has been reported in terminally differentiated rodent hepatocytes, yet remains a challenge in human hepatocytes. METHODS: Human hepatocytes were isolated from healthy and diseased donor livers and reprogrammed into progenitor cells by 2 small molecules, A83-01 and CHIR99021 (AC), in the presence of EGF and HGF. The stemness properties of human chemically derived hepatic progenitors (hCdHs) were tested by standard in vitro and in vivo assays and transcriptome profiling. RESULTS: We developed a robust culture system for generating hCdHs with therapeutic potential. The use of HGF proved to be an essential determinant of the fate conversion process. Based on functional evidence, activation of the HGF/MET signal transduction system collaborated with A83-01 and CHIR99021 to allow a rapid expansion of progenitor cells through the activation of the ERK pathway. hCdHs expressed hepatic progenitor markers and could self-renew for at least 10 passages while retaining a normal karyotype and potential to differentiate into functional hepatocytes and biliary epithelial cells in vitro. Gene expression profiling using RNAseq confirmed the transcriptional reprogramming of hCdHs towards a progenitor state and the suppression of mature hepatocyte transcripts. Upon intrasplenic transplantation in several models of therapeutic liver repopulation, hCdHs effectively repopulated the damaged parenchyma. CONCLUSION: Our study is the first report of successful reprogramming of human hepatocytes to a population of proliferating bipotent cells with regenerative potential. hCdHs may provide a novel tool that permits expansion and genetic manipulation of patient-specific progenitors to study regeneration and the repair of diseased livers. LAY SUMMARY: Human primary hepatocytes were reprogrammed towards hepatic progenitor cells by a combined treatment with 2 small molecules, A83-01 and CHIR99021, and HGF. Chemically derived hepatic progenitors exhibited a high proliferation potential and the ability to differentiate into hepatocytes and biliary epithelial cells both in vitro and in vivo. This approach enables the generation of patient-specific hepatic progenitors and provides a platform for personal and stem cell-based regenerative medicine.


Assuntos
Hepatócitos/citologia , Regeneração Hepática , Fígado/citologia , Células-Tronco/citologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Feminino , Quinase 3 da Glicogênio Sintase , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Modelos Animais , Pirazóis/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Tiossemicarbazonas/farmacologia
12.
PLoS Pathog ; 13(1): e1006126, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28125719

RESUMO

Tuberculosis is a global health problem and at least one-third of the world's population is infected with Mycobacterium tuberculosis (MTB). MTB is a successful pathogen that enhances its own intracellular survival by inhibiting inflammation and arresting phago-lysosomal fusion. We previously demonstrated that Toxoplasma gondii (T. gondii) dense granule antigen (GRA) 7 interacts with TNF receptor-associated factor 6 via Myeloid differentiation primary response gene 88, enabling innate immune responses in macrophages. To extend these studies, we found that GRA7 interacts with host proteins involved in antimicrobial host defense mechanisms as a therapeutic strategy for tuberculosis. Here, we show that protein kinase C (PKC)α-mediated phosphorylation of T. gondii GRA7-I (Ser52) regulates the interaction of GRA7 with PYD domain of apoptosis-associated speck-like protein containing a carboxy-terminal CARD, which is capable of oligomerization and inflammasome activation can lead to antimicrobial defense against MTB. Furthermore, GRA7-III interacted with the PX domain of phospholipase D1, facilitating its enzyme activity, phago-lysosomal maturation, and subsequent antimicrobial activity in a GRA7-III (Ser135) phosphorylation-dependent manner via PKCα. Taken together, these results underscore a previously unrecognized role of GRA7 in modulating antimicrobial host defense mechanism during mycobacterial infection.


Assuntos
Antígenos de Protozoários/metabolismo , Mycobacterium/imunologia , Proteína Quinase C-alfa/metabolismo , Proteínas de Protozoários/metabolismo , Toxoplasma/fisiologia , Tuberculose/imunologia , Animais , Antígenos de Protozoários/genética , Domínio de Ativação e Recrutamento de Caspases , Diferenciação Celular , Humanos , Imunidade Inata , Inflamassomos/imunologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Células Mieloides/imunologia , Fosforilação , Proteína Quinase C-alfa/genética , Proteínas de Protozoários/genética , Domínio Pirina , Fator 6 Associado a Receptor de TNF/genética , Fator 6 Associado a Receptor de TNF/metabolismo , Toxoplasma/genética , Toxoplasma/imunologia , Tuberculose/microbiologia
13.
Pharmacol Res ; 148: 104439, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31476369

RESUMO

The apoptosis alternate cell death pathways are extensively studied in recent years and their significance has been well recognized. With identification of newer cell death pathways, the therapeutic opportunities to modulate cell death have indeed further extended. Necroptosis, among other apoptosis alternate pathways, has been immensely studied recently in different hepatic disease models. Receptor-interacting protein 1 (RIPK1), RIPK3 and mixed lineage kinase domain like (MLKL) seemed to be the key players to mediate necroptosis pathway. Initially, necroptosis seemed to be following the typical pathway. But recently diverse pathways and outcomes have been observed. With recent studies reporting diverse outcomes, the necroptosis signalling has become a lot more interesting and intricate. The typical RIPK1 signalling followed by RIPK3 and MLKL might not always be strictly followed. Although, necroptosis signalling has been intensively investigated in various disease conditions; however, there is still a need to further elaborate and understand the unique scaffolding and kinase properties and other signalling interactions of necroptosis signalling molecules.


Assuntos
Hepatopatias/metabolismo , Necroptose/fisiologia , Transdução de Sinais/fisiologia , Animais , Humanos , Proteínas Quinases/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
14.
J Gastroenterol Hepatol ; 34(12): 2206-2218, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31132314

RESUMO

BACKGROUND AND AIM: Receptor-interacting serine/threonine kinase 3 and mixed lineage kinase domain-like pseudokinase (MLKL) have gained attention as apoptosis alternate cell death signaling molecules. We aimed to evaluate the role of MLKL in non-alcoholic fatty liver disease (NAFLD). METHODS: Hepatic tissue MLKL expression was compared between NAFLD patients and healthy controls. High-fat diet was fed to wild-type and MLKL-knockout (KO) mice for 12 weeks. Brown adipose fat tissue was measured by [18 F]-fluorodeoxyglucose positron emission tomography. Energy expenditure was measured by indirect calorimetry. Anti-MLKL effects were also evaluated in in vitro setting using U937 and HepG2 cells. RESULTS: Hepatic tissue MLKL expression increased in NAFLD patients compared with healthy controls. MLKL expression increased according to the degree of steatosis, ballooning, and inflammation. High-fat diet-fed MLKL-KO mice displayed decreased alanine aminotransferase, triglycerides, liver weight, NAFLD activity score (6.3 vs 3.5, P < 0.001), steatosis score (3.0 vs 1.8, P < 0.001), inflammation, and ballooning degeneration compared with wild-type mice. SREBP1c, fatty acid synthase, and SCD-1 expressions decreased in MLKL-KO mice. Adipose tissue F4/80-positive crown-like structures were also reduced in MLKL-KO mice. HepG2 cells treated with necrosulfonamide (an MLKL inhibitor) showed reduced Nile red staining and reduced SREBP1c and SCD-1 expressions. Stimulation of necroptosis using lipopolysaccharide + caspase inhibitor (zVAD) increased CXCL1/2 expressions in U937 monocyte cells. Lipopolysaccharide + zVAD-induced increased expressions of CXCL1/2 were reduced with necrosulfonamide treatment. CONCLUSIONS: Mixed lineage kinase domain-like pseudokinase inhibition has protective effects in non-alcoholic steatohepatitis by decreasing hepatic de novo fat synthesis and chemokine (C-X-C motif) ligand expressions.


Assuntos
Tecido Adiposo Marrom/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas Quinases/fisiologia , Acrilamidas/farmacologia , Animais , Estudos de Casos e Controles , Quimiocinas CXC/metabolismo , Dieta Hiperlipídica , Metabolismo Energético/fisiologia , Deleção de Genes , Células Hep G2 , Humanos , Ligantes , Lipídeos/biossíntese , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Necroptose/fisiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/deficiência , Proteínas Quinases/genética , Sulfonamidas/farmacologia , Células U937
15.
Dig Dis Sci ; 64(3): 781-791, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30421375

RESUMO

BACKGROUND: Injecting MSCs via blood vessel is most commonly used method, which has a major drawback of safety. The aim of our study was to evaluate efficacy using scaffold-loaded MSCs in acute liver failure model. METHOD: Acute liver failure was induced in mice using thioacetamide (TAA) (200 mg/kg, i.p) once a day for two consecutive days. The animals were divided in four acute liver failure groups: (1) TAA; (2) empty scaffold; (3) MSCs injected through tail vein; (4) MSC + Scaffold, scaffold loaded with MSCs, to evaluate the mortality and changes in liver function. Polylactic-co-glycolic acid scaffold alone and loaded with human MSCs was implanted on mice dorsum. RESULTS: TAA dose was titrated until one-third mortality rate was achieved. TAA (200 mg/kg) once daily for two consecutive days was injected to establish the acute liver failure model. The mortality of TAA and scaffold groups was 55.9% and 63.2%, respectively. Although, mortality of MSC-TV group decreased 14.7% as compared to TAA group (p = 0.200), MSC + Scaffold group had the lowest mortality (31.4%) (p = 0.013). Cells implanted in PLGA biomaterial were survived until 3 weeks, and their function was increased. Area of hepatic inflammation and necrosis was significantly reduced in MSC-TV and MSC + Scaffold groups; but there was no difference between the two groups. Gene expressions related to inflammation were significantly decreased in MSC-TV and MSC + Scaffold groups compared to TAA group. In MSC + Scaffold group, no migration of stem cells to liver tissue was observed. Although, not all cells in scaffold were stained, some of them were differentiated into hepatocyte-like cells which stained positive for PAS and CYP2E1 antibody. CONCLUSION: Scaffold loaded with MSCs showed protective effects via paracrine signaling on acute liver failure model.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/cirurgia , Falência Hepática Aguda/cirurgia , Regeneração Hepática , Fígado/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Alicerces Teciduais/química , Animais , Biomarcadores/metabolismo , Diferenciação Celular , Movimento Celular , Proliferação de Células , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Citocromo P-450 CYP2E1/metabolismo , Modelos Animais de Doenças , Humanos , Fígado/patologia , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/patologia , Camundongos Endogâmicos C57BL , Necrose , Comunicação Parácrina , Fenótipo , Tioacetamida
16.
J Korean Med Sci ; 34(2): e14, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30636945

RESUMO

BACKGROUND: The heterogeneity of histological findings in preclinical diet-induced nonalcoholic fatty liver disease (NAFLD) animal models is highly challenging. Here, we aimed to evaluate the feasibility and stability of repeated liver biopsy in NAFLD animal models. METHODS: Heterogeneity of diet-induced NAFLD was evaluated at different time points in 52 high-fat diet (HFD), 35 methionine choline-deficiency diet (MCD), and 166 western diet (WD) induced NAFLD mice. Serial liver biopsies (left lateral, right medial, and left medial lobes) were performed monthly for up to 3 months. Mortality rates and changes in food intake, body weight, and liver enzymes were assessed. RESULTS: At 12 weeks, of the HFD animals, 14% and 30% did not develop steatosis and lobular inflammation, respectively; of the MCD animals, 7% did not develop lobular inflammation; and of the WD animals, 14% and 51% did not develop steatosis and lobular inflammation, respectively. The mortality rate of repeated liver biopsy was 1.62% (2/123 mice died). Repeated liver biopsy can be used to trace disease progression. Although body weight, food intake, and liver enzymes slightly changed after biopsy, all recovered within a week. Repeated liver biopsy did not affect the degrees of inflammation and steatosis of the other liver lobes. CONCLUSION: The diet-induced NAFLD models were quite heterogeneous. Our results suggest that the repeated liver biopsy before treatment was applicable and stable in this NAFLD animal study.


Assuntos
Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Animais , Biópsia/métodos , Peso Corporal , Dieta Hiperlipídica , Modelos Animais de Doenças , Progressão da Doença , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
17.
Opt Lett ; 43(22): 5583-5586, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30439900

RESUMO

We present the enhanced performances of a vertical-illumination-type Ge-on-Si avalanche photodetector based on internal RF-gain effects operating up to 50 Gb/s. A fabricated Ge-on-Si avalanche photodetector (APD) exhibits three operational voltage regions associated with different aspects of the current (DC) gain and bandwidth characteristics. The measured current-voltage (I-V) curve of a Ge-on-Si APD exhibits a negative photoconductance (negative differential resistance [NDR]) in a high bias region beyond the avalanche breakdown voltage (V br ), where a device shows good eye openings up to 50 Gb/s (non-return-to-zero [NRZ] signal) with further improved signal-to-noise ratios and signal amplitudes. A ROSA packaged module, wherein a fabricated Ge-on-Si APD is wire-bonded to a commercial TIA with a ∼75% optical alignment for λ∼1310 nm and biased at a lower voltage than the V br , exhibits the sensitivities of -18.9 and -15.3 dBm for 30 and 35 Gb/s, respectively, and -13.9 dBm for 40 Gb/s at a 10-12 bit error rate. The experimental results indicate that considerable improvement in a module performance can be expected by utilizing the Ge-on-Si APD operated in the NDR region with a properly customized TIA.

18.
BMC Cancer ; 18(1): 1244, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30541499

RESUMO

BACKGROUND: SSBP2, single-stranded DNA binding protein 2, is a subunit of the ssDNA-binding complex that is involved in the maintenance of genome stability. The majority of previous studies have suggested a tumor-suppressive role of SSBP2, which is silenced by promoter hypermethylation in several human malignancies, such as hematologic malignancies, prostate cancer, esophageal squamous cell carcinoma, ovarian cancer, and gallbladder cancer. However, an oncogenic role of SSBP2 has been suggested in glioblastoma patients. We investigated the clinicopathologic significance of SSBP2 expression in hepatocellular carcinoma. METHODS: We constructed tissue microarrays consisting of 21 normal liver parenchyma and 213 hepatocellular carcinoma tissues with corresponding adjacent non-neoplastic tissues. SSBP2 expression was investigated by immunohistochemistry, and positive expression was defined as more than 10% of the tumor cells to show nuclear staining. We then analyzed the correlations between SSBP2 expression and various clinicopathologic characteristics, and further studied the role of SSBP2 in cell growth and migration. RESULTS: Hepatocytes were negative for SSBP2 immunohistochemistry in all normal liver samples, whereas the nuclei of normal bile duct epithelium and sinusoidal endothelium were immunoreactive. Positive immunoreactivity was found in one (0.6%) out of 180 non-neoplastic liver tissue samples adjacent to the tumor and in 16 (8.5%) out of 189 hepatocellular carcinomas. Positive SSBP2 expression was significantly correlated with tumor multifocality (P = 0.027, chi-square test), high histologic grade (P = 0.003, chi-square test), and frequent vascular invasion (P = 0.001, chi-square test). Kaplan-Meier survival curves revealed that patients with SSBP2 expression had poor prognosis in both disease-free and overall survival (P = 0.004 and P = 0.026, respectively, log-rank test). SSBP2-positive tumors also had a higher Ki-67 proliferation index (P <  0.001, t-test). Furthermore, downregulation of SSBP2 in the Huh7 cell line inhibited cell migration (P = 0.022, t-test) with altered expression of epithelial-mesenchymal transition markers. CONCLUSIONS: The minority of hepatocellular carcinomas expressed SSBP2 by immunohistochemistry, whereas normal hepatocytes were negative. SSBP2-positive hepatocellular carcinomas were significantly associated with aggressive phenotypes and poor clinical outcome.


Assuntos
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidade , Proteínas de Ligação a DNA/biossíntese , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Idoso , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Feminino , Seguimentos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Taxa de Sobrevida/tendências
19.
Opt Express ; 23(9): 12232-43, 2015 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-25969309

RESUMO

We present the hybrid-integrated silicon photonic receiver and transmitter based on silicon photonic devices and 65 nm bulk CMOS interface circuits operating over 30 Gb/s with a 10(-12) bit error rate (BER) for λ ~1550nm. The silicon photonic receiver, operating up to 36 Gb/s, is based on a vertical-illumination type Ge-on-Si photodetector (Ge PD) hybrid-integrated with a CMOS receiver front-end circuit (CMOS Rx IC), and exhibits high sensitivities of -11 dBm, -8 dBm, and -2 dBm for data rates of 25 Gb/s, 30 Gb/s and 36 Gb/s, respectively, at a BER of 10(-12). The measured energy efficiency of the Si-photonic receiver is 2.6 pJ/bit at 25 Gb/s with an optical input power of -11 dBm, and 2.1 pJ/bit at 36 Gb/s with an optical power of -2 dBm. The hybrid-integrated silicon photonic transmitter, comprised of a depletion-type Mach-Zehnder modulator (MZM) and a CMOS driver circuit (CMOS Tx IC), shows better than 5.7 dB extinction ratio (ER) for 25 Gb/s, and 3 dB ER for 36 Gb/s. The silicon photonic transmitter achieves the data transmission with less than 10(-15) BER at 25 Gb/s, 10(-14) BER at 28 Gb/s, and 6 x 10(-13) BER with the energy efficiency of ~6 pJ/bit at 30 Gb/s.

20.
BMC Neurol ; 15: 48, 2015 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-25886604

RESUMO

BACKGROUND: Chronic inflammatory demyelinating polyneuropathy (CIDP) is a rare complication of Crohn's disease (CD), and it is uncertain whether it is associated with CD itself or with its treatment. We describe a case of CIDP-like neuropathy as an initial symptom of CD. The neurologic symptoms of the patient which responded partially to intravenous immunoglobulin (IVIG) recovered after resection of the appendiceal CD. CASE PRESENTATION: A 17-year-old male had experienced three separate attacks of motor weakness and paresthesia of all four extremities over a period of 7 months. The electrophysiologic findings revealed a demyelinating sensory-motor polyneuropathy which was compatible with CIDP. However, repeated intravenous IVIG (2 g/kg) treatment gave only a partial response. Four days after the last discharge, he was diagnosed as appendiceal CD after surgical resection of a periappendiceal abscess. His neurologic symptoms and electrophysiologic findings recovered without any maintenance therapy. CONCLUSIONS: CIDP-like neuropathy can be an initial presentation of CD, and recovery of the CIDP symptoms may result from resection of the CD. Clinicians should be aware of the possibility of CD in patients with intractable CIDP symptoms.


Assuntos
Doença de Crohn/diagnóstico , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico , Abscesso Abdominal/etiologia , Abscesso Abdominal/cirurgia , Adolescente , Apendicectomia , Doença de Crohn/complicações , Doença de Crohn/cirurgia , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Masculino , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/tratamento farmacológico , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/etiologia
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