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1.
Braz. oral res. (Online) ; 34: e006, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1055522

RESUMO

Abstract Induced pluripotent stem (iPS) cells could be induced into ameloblast-like cells by ameloblasts serum-free conditioned medium (ASF-CM), and bone morphogenetic proteins (BMPs) might be essential during the regulation of this process. The present study investigates the signal transduction that regulates the ameloblastic differentiation of iPS cells induced by ASF-CM. Mouse iPS cells were characterized and then cultured for 14 days in epithelial cell medium (control) or ASF-CM. Bone morphogenetic protein receptor II (BMPR-II) siRNA, inhibitor of Smad1/5 phosphorylation activated by activin receptor-like kinase (ALK) receptors, and inhibitors of mitogen-activated protein kinases (MAPKs) phosphorylation were used to treat the iPS cells in combination with ASF-CM. Real-time PCR, western blotting, and immunofluorescent staining were used to evaluate the expressions of ameloblast markers ameloblastin, enamelin, and cytokeratin-14. BMPR-II gene and protein levels increased markedly in ASF-CM-treated iPS cells compared with the controls, while the mRNA levels of Bmpr-Ia and Bmpr-Ib were similar between the ASF-CM and control groups. ASF-CM stimulation significantly increased the gene and protein expression of ameloblastin, enamelin and cytokeratin-14, and phosphorylated SMAD1/5, p38 MAPK, and ERK1/2 MAPK compared with the controls. Knockdown of BMPR-II and inhibition of Smad1/5 phosphorylation both could significantly reverse the increased expression of ameloblastin, enamelin, and cytokeratin-14 induced by ASF-CM, while neither inhibition of p38 nor ERK1/2 phosphorylation had significant reversing effects. We conclude that smad1/5 signaling transduction, activated by ALK receptors, regulates the ameloblastic differentiation of iPS cells induced by ameloblast-conditioned medium.


Assuntos
Transdução de Sinais/fisiologia , Proteína Smad1/fisiologia , Células-Tronco Pluripotentes Induzidas/citologia , Ameloblastos/citologia , Fosforilação , Fatores de Tempo , Expressão Gênica , Diferenciação Celular/fisiologia , Diferenciação Celular/genética , Células Cultivadas , Western Blotting , Imunofluorescência , Meios de Cultura Livres de Soro , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sistema de Sinalização das MAP Quinases/fisiologia , Receptores de Ativinas/análise , Receptores de Ativinas/fisiologia , Interferência de RNA , Proteínas Quinases p38 Ativadas por Mitógeno/análise , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/análise , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/fisiologia , Proteína Smad1/análise
2.
Braz. j. med. biol. res ; 53(7): e9207, 2020. tab, graf
Artigo em Inglês | LILACS, Coleciona SUS | ID: biblio-1132533

RESUMO

The objective of this study was to investigate the relationship between PI3K/mTOR/RhoA signaling regulated cytoskeletal rearrangements and phagocytic capacity of macrophages. RAW264.7 macrophages were divided into four groups; blank control, negative control, PI3K-RNAi, and mTOR-RNAi. The cytoskeletal changes in the macrophages were observed. Furthermore, the phagocytic capacity of macrophages against Escherichia coli is reported as mean fluorescence intensity (MFI) and percent phagocytosis. Transfection yielded 82.1 and 81.5% gene-silencing efficiencies against PI3K and mTOR, respectively. The PI3K-RNAi group had lower mRNA and protein expression levels of PI3K, mTOR, and RhoA than the blank and negative control groups (Р<0.01). The mTOR-RNAi group had lower mRNA and protein levels of mTOR and RhoA than the blank and the negative control groups (Р<0.01). Macrophages in the PI3K-RNAi group exhibited stiff and inflexible morphology with short, disorganized filopodia and reduced number of stress fibers. Macrophages in the mTOR-RNAi group displayed pronounced cellular deformations with long, dense filopodia and an increased number of stress fibers. The PI3K-RNAi group exhibited lower MFI and percent phagocytosis than blank and negative control groups, whereas the mTOR-RNAi group displayed higher MFI and percent phagocytosis than the blank and negative controls (Р<0.01). Before and after transfection, the mRNA and protein levels of PI3K were both positively correlated with mTOR and RhoA (Р<0.05), but the mRNA and protein levels of mTOR were negatively correlated with those of RhoA (Р<0.05). Changes in the phagocytic capacity of macrophages were associated with cytoskeletal rearrangements and were regulated by the PI3K/mTOR/RhoA signaling pathway.


Assuntos
Humanos , Animais , Ratos , Fagocitose/fisiologia , Citoesqueleto/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Macrófagos/metabolismo , Transfecção , Transdução de Sinais , Western Blotting , Inativação Gênica , Interferência de RNA , Reação em Cadeia da Polimerase em Tempo Real , Células RAW 264.7 , Vetores Genéticos
3.
Braz. oral res. (Online) ; 34: e006, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1089380

RESUMO

Abstract Induced pluripotent stem (iPS) cells could be induced into ameloblast-like cells by ameloblasts serum-free conditioned medium (ASF-CM), and bone morphogenetic proteins (BMPs) might be essential during the regulation of this process. The present study investigates the signal transduction that regulates the ameloblastic differentiation of iPS cells induced by ASF-CM. Mouse iPS cells were characterized and then cultured for 14 days in epithelial cell medium (control) or ASF-CM. Bone morphogenetic protein receptor II (BMPR-II) siRNA, inhibitor of Smad1/5 phosphorylation activated by activin receptor-like kinase (ALK) receptors, and inhibitors of mitogen-activated protein kinases (MAPKs) phosphorylation were used to treat the iPS cells in combination with ASF-CM. Real-time PCR, western blotting, and immunofluorescent staining were used to evaluate the expressions of ameloblast markers ameloblastin, enamelin, and cytokeratin-14. BMPR-II gene and protein levels increased markedly in ASF-CM-treated iPS cells compared with the controls, while the mRNA levels of Bmpr-Ia and Bmpr-Ib were similar between the ASF-CM and control groups. ASF-CM stimulation significantly increased the gene and protein expression of ameloblastin, enamelin and cytokeratin-14, and phosphorylated SMAD1/5, p38 MAPK, and ERK1/2 MAPK compared with the controls. Knockdown of BMPR-II and inhibition of Smad1/5 phosphorylation both could significantly reverse the increased expression of ameloblastin, enamelin, and cytokeratin-14 induced by ASF-CM, while neither inhibition of p38 nor ERK1/2 phosphorylation had significant reversing effects. We conclude that smad1/5 signaling transduction, activated by ALK receptors, regulates the ameloblastic differentiation of iPS cells induced by ameloblast-conditioned medium.


Assuntos
Transdução de Sinais/fisiologia , Proteína Smad1/fisiologia , Células-Tronco Pluripotentes Induzidas/citologia , Ameloblastos/citologia , Fosforilação , Fatores de Tempo , Expressão Gênica , Diferenciação Celular/fisiologia , Diferenciação Celular/genética , Células Cultivadas , Western Blotting , Imunofluorescência , Meios de Cultura Livres de Soro , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sistema de Sinalização das MAP Quinases/fisiologia , Receptores de Ativinas/análise , Receptores de Ativinas/fisiologia , Interferência de RNA , Proteínas Quinases p38 Ativadas por Mitógeno/análise , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/análise , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/fisiologia , Proteína Smad1/análise
4.
Biomédica (Bogotá) ; 38(3): 388-397, jul.-set. 2018. graf
Artigo em Inglês | LILACS | ID: biblio-973992

RESUMO

Abstract Introduction: Cerebral ischemia is the third cause of death risk in Colombia and the first cause of physical disability worldwide. Different studies on the silencing of the cyclin-dependent kinase 5 (CDK5) have shown that reducing its activity is beneficial in ischemic contexts. However, its effect on neural cell production after cerebral ischemia has not been well studied yet. Objective: To evaluate CDK5 silencing on the production of neurons and astrocytes after a focal cerebral ischemia in rats. Materials and methods: We used 40 eight-week-old male Wistar rats. Both sham and ischemia groups were transduced at CA1 hippocampal region with an adeno-associated viral vector using a noninterfering (shSCRmiR) and an interfering sequence for CDK5 (shCDK5miR). We injected 50 mg/kg of bromodeoxyuridine intraperitoneally from hour 24 to day 7 post-ischemia. We assessed the neurological abilities during the next 15 days and we measured the immunoreactivity of bromodeoxyuridine (BrdU), doublecortin (DCX), NeuN, and glial fibrillary acid protein (GFAP) from day 15 to day 30 post-ischemia. Results: Our findings showed that CDK5miR-treated ischemic animals improved their neurological score and presented increased BrdU+ cells 15 days after ischemia, which correlated with higher DCX and lower GFAP fluorescence intensities, and, although mature neurons populations did not change, GFAP immunoreactivity was still significantly reduced at 30 days post-ischemia in comparison with untreated ischemic groups. Conclusion: CDK5miR therapy generated the neurological recovery of ischemic rats associated with the induction of immature neurons proliferation and the reduction of GFAP reactivity at short and longterm post-ischemia.


Resumen Introducción. La isquemia cerebral es la tercera causa de riesgo de muerte en Colombia y la primera causa de discapacidad física en el mundo. En diversos estudios en los que se silenció la cinasa 5 dependiente de la ciclina (CDK5) se ha demostrado que la reducción de su actividad es beneficiosa frente a la isquemia. Sin embargo, su efecto sobre la neurogénesis después de la isquemia no se ha dilucidado suficientemente. Objetivo. Evaluar el silenciamiento de la CDK5 en la neurogénesis y la gliogénesis después de la isquemia cerebral focal en ratas. Materiales y métodos. Se usaron 40 machos de rata Wistar de ocho semanas de edad. Los grupos de control y los isquémicos sometidos a transducción en la región del hipocampo CA1, se inyectaron intraperitonealmente por estereotaxia con 50 mg/kg de bromodesoxiuridina (BrdU) a partir de las 24 horas y hasta el día 7 después de la isquemia, con un vector viral asociado a adenovirus usando una secuencia no interferente (SCRmiR) y una interferente (CDK5miR). Se evaluó la capacidad neurológica durante los quince días siguientes y se detectó la capacidad de inmunorreacción para la BrdU, la proteína doblecortina (DCX), los núcleos neuronales (NeuN), y la proteína fibrilar acídica de la glía (Glial Fibrillary Acidic Protein, GFAP) a los 15 y 30 días de la isquemia. Resultados. Los animales isquémicos tratados con CDK5miR mejoraron su puntuación neurológica y presentaron un incremento de la BrdU+ a los 15 días de la isquemia, lo cual se correlacionó con una mayor intensidad de la DCX+ y una menor de la GFAP+. No hubo modificación de los NeuN+, pero sí una reducción significativa de la GFAP+ a los 30 días de la isquemia en los animales tratados comparados con los animales isquémicos no tratados. Conclusión. La terapia con CDK5miR generó la recuperación neurológica de ratas isquémicas asociada con la inducción de la neurogénesis y el control de la capacidad de reacción de la proteína GFAP a corto y largo plazo después de la isquemia.


Assuntos
Animais , Masculino , Ratos , Terapia Genética , Isquemia Encefálica/terapia , Neuroglia/fisiologia , RNA Interferente Pequeno/uso terapêutico , Interferência de RNA , Quinase 5 Dependente de Ciclina/antagonistas & inibidores , Neurogênese/genética , Terapia de Alvo Molecular , Vetores Genéticos/uso terapêutico , Biomarcadores , Terapia Genética/métodos , Isquemia Encefálica/genética , Isquemia Encefálica/patologia , Astrócitos/patologia , Estenose das Carótidas , Ratos Wistar , Dependovirus/genética , RNA Interferente Pequeno/administração & dosagem , Replicação do DNA , Avaliação de Medicamentos , Quinase 5 Dependente de Ciclina/genética , Terapia de Alvo Molecular/métodos , Proteína Duplacortina , Ligadura , Neurônios/patologia
5.
Electron. j. biotechnol ; 35: 25-32, sept. 2018. graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1047765

RESUMO

Background: Pollen development is an important reproductive process that directly affects pollen fertility and grain yield in rice. Argonaute (AGO) proteins, the core effectors of RNA-mediated silencing, play important roles in regulating plant growth and development. However, few AGO proteins in rice were reported to be involved in pollen development. In this study, artificial microRNA technology was used to assess the function of OsAGO17 in pollen development. Results: In this study, OsAGO17, a rice-specific gene, was specifically expressed in rice pollen grains, with the highest expression in uninucleate microspores. Downregulation of OsAGO17 by artificial microRNA technology based on the endogenous osa-miRNA319a precursor was successfully achieved. It is found that downregulation of OsAGO17 could significantly affect pollen fertility and cause pollen abortion, thus suggesting that OsAGO17 functions in rice pollen development. In addition, the downregulation of OsAGO17 mainly caused a low seed-setting rate, thereby resulting in the reduction of grain yield, whereas the downregulation of OsAGO17 did not significantly affect rice vegetative growth and other agricultural traits including number of florets per panicle, number of primary branch per panicle, and 100-grain weight. Furthermore, the result of subcellular localization analysis indicated that the OsAGO17 protein was localized to both the nucleus and the cytoplasm. Conclusion: These results represent the first report of the biological function for OsAGO17 in rice and indicate that OsAGO17 may possibly play crucial regulatory roles in rice pollen development. It helps us to better understand the mechanism of pollen development in rice.


Assuntos
Pólen/crescimento & desenvolvimento , Oryza/crescimento & desenvolvimento , Regulação para Baixo , Proteínas Argonautas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , MicroRNAs , Interferência de RNA , Fertilidade , Proteínas Argonautas/genética
6.
Braz. j. med. biol. res ; 51(6): e7080, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-889093

RESUMO

Prostate cancer (PCa) is the second leading cause of cancer death in men. Irradiation is one of the available options for treatment of PCa, however, approximately 10-45% of PCa are resistant to irradiation. We aimed to explore the role of long non-coding RNA highly upregulated in liver cancer (HULC) in the sensitivity of PCa cells to irradiation. Survival rate, cell apoptosis, cycle, expressions of related proteins, and caspase-3 activity were assessed to explore the effects of HULC on sensitivity of PCa cells to irradiation. Expression of HULC in DU-145, PC3, LNCaP, and RWPE-1 cells was determined and the influence of HULC on DU-145 cells was explored. Then, PC3 cells aberrantly expressing HULC were implanted into NOD-SCID mice for tumor xenograft study. Changes of autophagy after aberrant expression of HULC in vivo and in vitro were tested. Furthermore, the interacted protein of HULC and involved signaling pathway were investigated. In PC3 and LNCaP cells under irradiation, survival rate and cell cycle were decreased and apoptosis was increased by HULC knockdown. HULC knockdown arrested PC3 cells at G0/G1 phase. DU-145 was sensitive to irradiation, and resistance to irradiation of DU-145 cells was enhanced by HULC overexpression. Moreover, HULC knockdown enhanced the sensitivity of PC3 xenografts to irradiation. HULC knockdown promoted autophagy through interaction with Beclin-1 and inhibition of mTOR, resulting in increased apoptosis. HULC knockdown improved sensitivity of PCa cells to irradiation both in vivo and in vitro. HULC suppressed Beclin-1 phosphorylation, thereby reduced autophagy, involving the mTOR pathway.


Assuntos
Humanos , Masculino , Autofagia/efeitos da radiação , Neoplasias da Próstata/patologia , Tolerância a Radiação/fisiologia , RNA Longo não Codificante/efeitos da radiação , Apoptose/efeitos da radiação , Western Blotting , Linhagem Celular Tumoral/efeitos da radiação , Reação em Cadeia da Polimerase em Tempo Real , Interferência de RNA/efeitos da radiação , Transfecção
7.
São Paulo; s.n; s.n; 2018. 174 p. graf, tab, ilus.
Tese em Português | LILACS | ID: biblio-996534

RESUMO

O adenocarcinoma ductal pancreático (PDAC, pancreatic ductal adenocarcinoma), o tipo mais prevalente de câncer do pâncreas, é uma neoplasia extremamente agressiva e com elevado índice de letalidade. Há uma necessidade premente de identificação de vulnerabilidades no PDAC que possam ser exploradas como alvos terapêuticos, e a utilização de modelos pré-clínicos que recapitulem a complexidade biológica e heterogeneidade clínica da doença é um aspecto central para a realização dessa tarefa. Os xenotransplantes de tecido tumoral derivado de pacientes (PDX, patient-derived tumor tissue xenografts), realizados em camundongos imunodeficientes, replicam com grande similaridade as principais características do tumor original e, assim, constituem uma ferramenta valiosa para o teste de drogas e estudos funcionais. Neste trabalho, 17 amostras cirúrgicas de PDAC humano foram implantadas subcutaneamente em camundongos nude atímicos. Sete tumores (41%) foram enxertados com sucesso e têm sido mantidos em sucessivas gerações de animais receptores. O exame histológico de seis desses xenoenxertos identificou características morfológicas compatíveis com os padrões reconhecidos no PDAC humano, assim como uma consistente similaridade de seu status de diferenciação histológica em relação aos perfis verificados nos tumoresoriginais. O cultivo in vitro de células derivadas de um dos xenotumores resultou em uma nova linhagem de câncer de pâncreas, com morfologia e cinética de crescimento comparáveis às de outras linhagens celulares de câncer pancreático. O potencial tumorigênico dessa nova linhagem foi validado in vivo, com uma consistente formação de tumores após inoculação em camundongos nude. A fim de aproveitar esse recurso para a investigação de potenciais alvos terapêuticos no PDAC, um rastreamento de vulnerabilidades moleculares foi realizado por meio de silenciamento gênico em larga-escala com RNA de interferência (RNAi). Uma biblioteca lentiviral de 4492 shRNAs (short hairpin RNAs), alvejando cerca de 350 genes envolvidos na regulação epigenética, foi empregada para a triagem de genes de suscetibilidade nas células derivadas de PDX, e em outras cinco linhagens tumorais pancreáticas (AsPC-1, BxPC-3, Capan-1, MIA PaCa-2 e PANC-1). Inicialmente, foi realizada uma série de experimentos preliminares, visando à amplificação e controle de qualidade da biblioteca de silenciamento, à produção de vetores lentivirais e à padronização das condições experimentais para a transdução e seleção das células-alvo. Apenas três das linhagens avaliadas (AsPC-1, MIA PaCa-2 e PANC-1) mostraram-se permissíveis à transdução pelos vetores lentivirais, e foram assim utilizadas no screening de alvos epigenéticos. A análise dos dados obtidos nesse ensaio está em curso e os resultados serão utilizados para a definição de potenciais alvos candidatos. Em conclusão, recursos valiosos para apoiar a pesquisa sobre o câncer de pâncreas foram desenvolvidos. A coleção de PDXs estabelecida, bem como a linhagem celular recém-derivada, constituem uma fonte permanente e estável de células de PDAC para análises moleculares e estudos funcionais que busquem elucidar aspectos da doença ainda pouco compreendidos. Adicionalmente, os reagentes gerados e a expertise adquirida com os ensaiosrealizados com a biblioteca de shRNAs contra alvos epigenéticos serão de grande utilidade em futuras investigações para identificar genes com funções importantes na manutenção do fenótipo tumoral, e consequentemente com potencial para serem explorados terapeuticamente


Pancreatic ductal adenocarcinoma (PDAC), the most prevalent type of pancreatic cancer, is a highly aggressive and lethal neoplasm. There is a pressing need to identify vulnerabilities in PDAC suited to be exploited as therapeutic targets, and the use of preclinical models recapitulating the biological complexity and clinical heterogeneity of the disease is central to this task. Patient-derived tumor tissue xenografts (PDX), established in immunodeficient mice, replicate with great similarity the main characteristics of the original tumor and thus constitute a valuable tool for drug testing and functional studies. In this work, 17 surgical samples of human PDAC were implanted subcutaneously in athymic nude mice. Seven tumors (41%) were successfully grafted and have been maintained through successive generations of recipient animals. Histological examination of six of these xenografts identified morphological characteristics compatible with the recognized patterns of human PDAC, as well as a consistent similarity of their histological differentiation status in relation to the profiles verified in the original tumors. In vitro culture of cells derived from one of these xenografts resulted in a new pancreatic cancer cell line, with morphology and growth kinetics comparable to those of other pancreatic tumor cells. The tumorigenic potential of this freshly derived cell line was validated in vivo, with a consistent tumor formation following inoculation into nude mice. To take advantage ofthis resource to investigate potential therapeutic targets in PDAC, a screening of molecular vulnerabilities was performed through large-scale gene silencing with RNA interference (RNAi). A lentiviral library containing 4492 short hairpin RNAs (shRNAs), targeting about 350 genes involved in epigenetic regulation, was employed for the search of susceptibility genes in the PDX-derived cells and in other five pancreatic tumor cell lines (AsPC-1, BxPC -3, Capan-1, MIA PaCa-2 and PANC-1). Initially, a series of preliminary experiments were carried out aiming at the amplification and quality control of the silencing library, production of lentiviral vectors and adjustment of the experimental conditions for transduction and selection of the target cells. Only three of the cell lines evaluated (AsPC-1, MIA PaCa-2 and PANC-1) were permissible for transduction by the lentiviral vectors, and were accordingly used in the screening of epigenetic targets. The analysis of data obtained in this trial is ongoing and the results will be used for definition of potential candidate targets. In conclusion, valuable resources to support research on pancreatic cancer have been developed. The established collection of PDXs as well as the newly derived cell line constitutes a permanent and stable source of PDAC cells for molecular analyzes and functional studies seeking to elucidate aspects of this disease that are still poorly understood. Additionally, both the reagents generated and the expertise gained from the RNAi assay against epigenetic targets will have inordinate usefulness in future investigations to identify genes with major functions in maintaining the malignant phenotype, and consequently with the potential to be exploited therapeutically


Assuntos
Animais , Feminino , Camundongos , Neoplasias Pancreáticas/fisiopatologia , Linhagem Celular Tumoral/classificação , Xenoenxertos/metabolismo , Transplante Heterólogo/instrumentação , Biblioteca Gênica , RNA Interferente Pequeno , Interferência de RNA , Epigenômica/normas
8.
Braz. j. med. biol. res ; 51(2): e6768, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-889019

RESUMO

This study aimed to investigate the mechanism of hypoxia-inducible factor-1 alpha (HIF-1α) mediated hypoxia-induced permeability changes in bladder endothelial cells. Models of in vitro hypoxic cell culture of bladder cancer, bladder cancer cells with low HIF-1α expression and HIF-1α RNA interference (RNAi) expression vector were established. Western blot and reverse transcription polymerase chain reaction (RT-PCR) were used to detect the expression of HIF-1α and vascular endothelial growth factor (VEGF) in each group. Bladder cell permeability was determined. Results showed that protein and mRNA expression of HIF-1α and VEGF at 3 and 12 h of hypoxia were significantly higher than normal control (P<0.05), and peaked at 12 h. HIF-1α and VEGF expression in the hypoxic group and hypoxic+3-(5′-hydroxymethyl-2′-furyl)-1-benzyl indazole (YC-1) group were significantly higher than normal control (P<0.05), while expression in the hypoxic+YC-1 group was significantly lower than the hypoxic group (P<0.05). Bladder cell permeability in the hypoxic and hypoxic+YC-1 group were significantly increased compared to normal control (P<0.05), while in the hypoxic+YC-1 group was significantly decreased compared to the hypoxic group (P<0.05). Most of the cells in the stably transfected HIF-1α RNAi expression vector pcDNA6.2-GW/EmGFP-miR-siHIF-1α expressed green fluorescence protein (GFP) under fluorescence microscope. pcDNA6.2-GW/EmGFP-miR-siHIF-1α could significantly inhibit HIF-1α gene expression (P<0.05). HIF-1α and VEGF expression in the hypoxic group and siHIF-1α hypoxic group were significantly higher than normal group (P<0.05), while expression in the siHIF-1α hypoxic group was significantly lower than the hypoxic group (P<0.05). Findings suggest that HIF-1α is an important factor in the increase of bladder cancer cell permeability.


Assuntos
Animais , Ratos , Neoplasias da Bexiga Urinária/metabolismo , Células Endoteliais/fisiologia , Fator A de Crescimento do Endotélio Vascular/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Hipóxia Tumoral/fisiologia , Permeabilidade , Regulação Neoplásica da Expressão Gênica/fisiologia , Western Blotting , Interferência de RNA , Linhagem Celular Tumoral , Células Endoteliais/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Reação em Cadeia da Polimerase em Tempo Real
9.
Biol. Res ; 51: 2, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-888428

RESUMO

Abstract Background This study determined the regulatory effects of inducible T-cell co-stimulators (ICOS) in human hepatocellular carcinoma HepG2 cells using a RNA interference (RNAi) technique. Methods A RNAi technique was used to knockdown the expression of ICOS. ICOS expression after knockdown was detected as mRNA and protein levels by RT-PCR and Western blot, respectively. A MTT colorimetric assay was used to detect cell proliferation, and the Transwell assay was used to detect cell invasion. Western blot was carried out to detect the level of Bcl-2, AKT, and PI3K protein expression in different groups. Results The proliferation of HepG2 cells were significantly decreased after ICOS siRNA transfection (EG group). Similarly, the results of the Transwell experiment showed that invasion of HepG2 cells in the EG group was clearly reduced compared to the negative control (NC) and blank control groups (CON). Western blot analysis showed that knockdown of ICOS expression reduced the levels of Bcl-2 and AKT, and also significantly up-regulated the level of PI3K phosphorylation (P < 0.01). Conclusion Down-regulating ICOS expression in HepG2 cells suppressed cell proliferation and invasion. The underlying mechanism may be related to the expression of the downstream factor, PI3K/AKT.


Assuntos
Humanos , Regulação Neoplásica da Expressão Gênica/genética , Carcinoma Hepatocelular/patologia , Proteína Coestimuladora de Linfócitos T Induzíveis/fisiologia , Neoplasias Hepáticas/patologia , Regulação para Baixo , Western Blotting , Colorimetria , Carcinoma Hepatocelular/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/sangue , Fosfatidilinositol 3-Quinases/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Interferência de RNA , Proliferação de Células , Proteínas Proto-Oncogênicas c-akt/sangue , Técnicas de Silenciamento de Genes , Células Hep G2 , Proteína Coestimuladora de Linfócitos T Induzíveis/genética , Neoplasias Hepáticas/metabolismo , Invasividade Neoplásica
10.
Electron. j. biotechnol ; 28: 113-119, July. 2017. tab, ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1015986

RESUMO

Background: C4ST-1 catalyzes the transfer of sulfate groups in the sulfonation of chondroitin during chondroitin sulfate synthesis. Chondroitin sulfate consists of numerous copies of negatively charged sulfonic acid groups that participate in the nucleation process of biomineralization. In the present study, we obtained two CHST11 genes (PmCHST11a and PmCHST11b) which encoded the C4ST-1 and explored the functions of these genes in the synthesis of chondroitin sulfate and in the formation of the nacreous layer of shells. Results: Both PmCHST11a and PmCHST11b had a sulfotransferase-2 domain, a signal peptide and a transmembrane domain. These properties indicated that these genes localize in the Golgi apparatus. Real-time PCR revealed that both PmCHST11a and PmCHST11b were highly expressed in the central zone of the mantle tissue. Inhibiting PmCHST11a and PmCHST11b via RNA interference significantly decreased the expression levels of these genes in the central zone of the mantle tissue and the concentration of chondroitin sulfate in extrapallial fluid. Moreover, shell nacre crystallized irregularly with a rough surface after RNA interference. Conclusions: This study indicated that PmCHST11a and PmCHST11b are involved in the nacre formation of Pinctada fucata martensii through participating in the synthesis of chondroitin sulfate.


Assuntos
Sulfotransferases/metabolismo , Pinctada , Nácar/biossíntese , Proteoglicanas de Sulfatos de Condroitina/biossíntese , Sulfotransferases/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Interferência de RNA , Reação em Cadeia da Polimerase em Tempo Real , Biomineralização
11.
Braz. j. microbiol ; 48(3): 566-569, July-Sept. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889146

RESUMO

Abstract The aim of this study was to assess the in vitro and in vivo effects of short-interfering RNAs (siRNAs) against rabies virus phosphoprotein (P) mRNA in a post-infection treatment for rabies as an extension of a previous report (Braz J Microbiol. 2013 Nov 15;44(3):879-82). To this end, rabies virus strain RABV-4005 (related to the Desmodus rotundus vampire bat) were used to inoculate BHK-21 cells and mice, and the transfection with each of the siRNAs was made with Lipofectamine-2000™. In vitro results showed that siRNA 360 was able to inhibit the replication of strain RABV-4005 with a 1 log decrease in virus titter and 5.16-fold reduction in P mRNA, 24 h post-inoculation when compared to non-treated cells. In vivo, siRNA 360 was able to induce partial protection, but with no significant difference when compared to non-treated mice. These results indicate that, despite the need for improvement for in vivo applications, P mRNA might be a target for an RNAi-based treatment for rabies.


Assuntos
Animais , Fosfoproteínas/genética , Raiva/veterinária , Vírus da Raiva/genética , Proteínas Virais/genética , Quirópteros/virologia , RNA Interferente Pequeno/genética , Interferência de RNA , Fosfoproteínas/metabolismo , Raiva/virologia , Vírus da Raiva/fisiologia , Proteínas Virais/metabolismo , Replicação Viral , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo
12.
Electron. j. biotechnol ; 26: 40-45, Mar. 2017. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1009000

RESUMO

Background: Ethylene plays an important role in the regulation of floral organ development in soybean, and 1-aminocyclopropane-1-carboxylate synthase (ACS) is a rate-limiting enzyme for ethylene biosynthesis. However, whether ACS also regulates floral organ differentiation in soybean remains unknown. To address this, we constructed an RNAi vector to inhibit ACS expression in cotyledonary nodes. Linear DNA cassettes of RNAi-ACS obtained by PCR were used to transform soybean cotyledonary nodes. Results: In total, 131 of 139 transiently transformed plants acquired herbicide resistance and displayed GUS activities in the new buds. In comparison to untransformed seedling controls, a greater number of flower buds were differentiated at the cotyledonary node; GM-ACS1 mRNA expression levels and ethylene emission in the transformed buds were reduced. Conclusion: These results indicate that the cotyledonary node transient transformation system may be suitable for stable transformation and that the inhibition of ACS expression may be an effective strategy for promoting floral organ differentiation in soybean.


Assuntos
Soja/enzimologia , Soja/genética , Interferência de RNA , Liases/metabolismo , Soja/crescimento & desenvolvimento , Transformação Genética , Expressão Gênica , Diferenciação Celular , Reação em Cadeia da Polimerase , Regulação da Expressão Gênica de Plantas , Etilenos/biossíntese , Resistência a Herbicidas , Vetores Genéticos , Glucuronidase
13.
Mem. Inst. Oswaldo Cruz ; 112(1): 1-7, Jan. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-841758

RESUMO

Insects are considered pests globally, implicated in the destruction of agricultural fields and transmission of pathogens that cause deadly human diseases, such as dengue, Zika and malaria. The diversity of the insecticide arsenal has remained stagnant for decades, but the recent rise of insecticide resistance fueled the discovery of novel modes of action, and the power of genomics has reinvigorated this search. This review discusses the importance of comparative and functional insect genomics in the identification of potential gene targets for an insecticidal mode of action with low off-target toxicity. Due to the global participation in the sequencing and annotation of insect genomes, the targeting of specific genes with molecular tools like RNAi and CRISPR/Cas9 for genome engineering and consequent functional identification and validation has become more efficient. While there are multiple avenues to explore for insecticidal candidates, this review identifies G-protein coupled receptors as attractive targets, and hones in on the octopamine and dopamine receptors due to their potential.


Assuntos
Animais , Marcação de Genes/métodos , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Resistência a Inseticidas , Controle de Insetos/métodos , Interferência de RNA , Genoma de Inseto , Inseticidas
15.
Arch. argent. pediatr ; 113(3): e137-e139, jun. 2015.
Artigo em Espanhol | LILACS | ID: lil-750470

RESUMO

El síndrome de Wiskott-Aldrich es una inmunodeficiencia primaria; con una incidencia de 3,5 a 5,2 por cada millón de recién nacidos masculinos. Se caracteriza por tener un patrón de herencia recesiva ligada al cromosoma X. En estos pacientes; se ha descrito la tríada clásica de inmunodeficiencia; microtrombocitopenia y eczema. Presentamos un paciente de 5 años de edad; hispánico; con antecedentes de numerosas infecciones desde el primer año de vida. Actualmente; presenta desnutrición crónica; talla baja secundaria y retraso en el desarrollo del lenguaje. Se diagnosticó una mutación poco frecuente del gen asociado al síndrome de Wiskott-Aldrich.


The Wiskott-Aldrich syndrome is a rare X-linked recessive immunodeficiency, with an estimated incidence of 3.5 to 5.2 cases per million males. It is characterizedby immunodeficiency, microthrombocytopenia and eczema. We present a 5-year-old Hispanic male, with a medical history of numerous infectious diseases, compromised health, chronic malnutrition, language delay and failure to thrive. An infrequent mutation in the Wiskott-Aldrich syndrome gene was found.


Assuntos
Animais , Embrião de Galinha , Proteínas Aviárias/metabolismo , Caderinas/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Proteínas Aviárias/antagonistas & inibidores , Proteínas Aviárias/genética , Sequência de Bases , Contagem de Células , Caderinas/antagonistas & inibidores , Caderinas/genética , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Tubo Neural/citologia , Tubo Neural/embriologia , Tubo Neural/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Interferência de RNA , RNA Interferente Pequeno/genética , Transdução de Sinais
16.
Int. arch. otorhinolaryngol. (Impr.) ; 19(2): 161-165, Apr-Jun/2015. tab
Artigo em Inglês | LILACS | ID: lil-747147

RESUMO

Introduction Literature data are not conclusive as to the influence of neonatal complications in the maturational process of the auditory system observed by auditory brainstem response (ABR) in infants at term and preterm. Objectives Check the real influence of the neonatal complications in infants by the sequential auditory evaluation. Methods Historical cohort study in a tertiary referral center. A total of 114 neonates met inclusion criteria: treatment at the Universal Neonatal Hearing Screening Program of the local hospital; at least one risk indicator for hearing loss; presence in both evaluations (the first one after hospital discharge from the neonatal unit and the second one at 6 months old); all latencies in ABR and transient otoacoustic emissions present in both ears. Results The complications that most influenced the ABR findings were Apgar scores less than 6 at 5 minutes, gestational age, intensive care unit stay, peri-intraventricular hemorrhage, and mechanical ventilation. Conclusion Sequential auditory evaluation is necessary in premature and term newborns with risk indicators for hearing loss to correctly identify injuries in the auditory pathway. .


Assuntos
Animais , Humanos , Camundongos , Carcinoma in Situ/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Proteínas de Transporte/metabolismo , Proteínas dos Microfilamentos/metabolismo , Neoplasias Pancreáticas/metabolismo , Fatores de Transcrição/metabolismo , Linhagem Celular Tumoral , Carcinoma in Situ/genética , Carcinoma in Situ/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/secundário , Proteínas de Transporte/genética , Modelos Animais de Doenças , Progressão da Doença , Transição Epitelial-Mesenquimal , Camundongos Knockout , Proteínas dos Microfilamentos/deficiência , Proteínas dos Microfilamentos/genética , Invasividade Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Prognóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Pseudópodes/metabolismo , Interferência de RNA , Análise de Sobrevida , Fatores de Tempo , Transfecção , Fatores de Transcrição/genética
17.
Int. braz. j. urol ; 41(2): 288-295, Mar-Apr/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-748299

RESUMO

Purposes To examine the factors related to the choice of cytoreductive nephrectomy (CN) for patients with metastatic clear cell renal cell carcinoma (mCCRCC), and compare the population-based survival rates of patients treated with or without surgery in the modern targeted therapy era. Materials and Methods From 2006 to 2009, patients with mCCRCC were identified from SEER database. The factors that affected patients to be submitted to CN were examined and propensity scores for each patient were calculated. Then patients were matched based upon propensity scores. Univariable and multivariable cox regression models were used to compare survival rates of patients treated with or without surgery. Finally, sensitivity analysis for the cox model on a hazard ratio scale was performed. Results Age, race, tumor size, T stage and N stage were associated with nephrectomy univariablely. After the match based upon propensity scores, the 1-, 2-, and 3-year cancer-specific survival rate estimates were 45.1%, 27.9%, and 21.7% for the no-surgery group vs 70.6%, 52.2%, and 41.7% for the surgery group, respectively (hazard ratio 0.42, 95%CI: 0.35-0.52, log-rank P<0.001). In multivariable Cox proportional hazard regression model, race, T stage, N stage and median household income were significantly associated with survival. Sensitivity analysis on a hazard ratio scale indicated that the hazard ratio might be above 1.00 only when the unknown factor had an opposite effect on survival which was 3-fold than CN. Conclusion The results of our study showed that CN significantly improves the survival of patients with metastatic CCRCC even in the targeted therapy era. .


Assuntos
Feminino , Humanos , Masculino , Pessoa de Meia-Idade , /genética , Movimento Celular , Proliferação de Células , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Interferência de RNA , /metabolismo , Linhagem Celular Tumoral , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Regulação Neoplásica da Expressão Gênica , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Fatores de Risco , RNA Mensageiro/metabolismo , Fatores de Tempo , Transfecção
18.
Cad. saúde pública ; 31(3): 597-606, 03/2015. tab
Artigo em Português | LILACS | ID: lil-744836

RESUMO

Foi avaliada a associação entre menopausa e insônia e a influência de variáveis socioeconômicas e psicossociais, em estudo transversal com 2.190 funcionárias de uma universidade (Estudo Pró-Saúde), a partir de um questionário autopreenchível com variáveis sobre menopausa, insônia, transtorno mental comum, eventos de vida estressantes, apoio social e variáveis socioeconômicas. Odds ratios foram calculados por meio de regressão logística multivariada, com desfecho politômico. Após ajuste para potenciais confundidoras sociodemográficas, mulheres na menopausa há mais de 60 meses apresentaram maior chance de reportar queixas de sono frequentes (OR entre 1,53 e 1,86) do que as que estavam na menopausa há menos de 60 meses. Após os ajustes, no primeiro grupo, para as variáveis psicossociais, a magnitude dos ORs reduziu para 1,53 (IC95%: 0,92-2,52) para dificuldade em iniciar o sono, 1,81 (IC95%: 1,09-2,98) para dificuldade em manter o sono e 1,71 (IC95%: 1,08-2,73) para queixa geral de insônia. Fatores psicossociais podem mediar a manifestação da insônia em mulheres na menopausa.


This study evaluated the association between insomnia and menopausal status and the influence of socioeconomic and psychosocial variables on this association in a cross-sectional analysis of 2,190 university employees (the Pró-Saúde Study). A self-administered questionnaire was used, covering menopausal status, complaints of insomnia, common mental disorders, stressful life events, social support, and socioeconomic variables. Odds ratios were calculated using logistic regression with a polytomous outcome. After adjusting for potential socio-demographic confounders, women who had entered menopause more than 60 months previously were more likely to report complaints with sleep (OR 1.53-1.86) as compared to women in menopause for less than 60 months. After adjusting for psychosocial variables, in the first group the ORs decreased to 1.53 (95%CI: 0.92-2.52) for difficulty initiating sleep, 1.81 (95%CI: 1.09-2.98) for difficulty maintaining sleep, and 1.71 (95%CI: 1.08-2.73) for general complaints of insomnia. Psychosocial factors can mediate the manifestation of insomnia among menopausal women.


En este estudio se evaluó la asociación entre insomnio y menopausia y la influencia de las variables socioeconómicas y psicosociales, en un estudio transversal con 2.190 mujeres de una universidad (Estudio Pro-Salud), a partir de un cuestionario autoadministrado con variables de la menopausia, insomnio, trastornos mentales, situaciones de estrés vital, apoyo social y variables socioeconómicas. Se calcularon los odds ratio mediante regresión logística multivariante con desenlace politómico. Después de ajustar por factores de confusión sociodemográficos potenciales, las mujeres menopáusicas desde hace más de 60 meses fueron más propensas a reportar quejas frecuentes de sueño (OR entre 1,53 y 1,86) que las menopáusicas hace menos de 60 meses. Después de los ajustes, en el primer grupo, para las variables psicosociales la magnitud de los OR se redujo a 1,53 (IC95%: 0,92-2,52) para la dificultad para iniciar el sueño, un 1,81 (IC95%: 1,09-2,98) para mantener el sueño y un 1,71 (IC95%: 1,08-2,73) para las quejas de insomnio en general. Los factores psicosociales pueden mediar en la manifestación del insomnio en las mujeres menopáusicas.


Assuntos
Animais , Camundongos , Córtex Cerebral/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas dos Microfilamentos/metabolismo , Microtúbulos/metabolismo , Neurogênese , Neurônios/metabolismo , Pseudópodes/metabolismo , Actinas/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Córtex Cerebral/embriologia , Drosophila , Proteínas de Drosophila/genética , /metabolismo , Cones de Crescimento/metabolismo , Mutação , Proteínas dos Microfilamentos/genética , Interferência de RNA
19.
Salud colect ; 11(1): 9-21, ene.-mar. 2015.
Artigo em Espanhol | LILACS | ID: lil-746681

RESUMO

El fortalecimiento mundial de la patente farmacéutica tensiona el acceso a los medicamentos esenciales. De acuerdo a este trabajo ello ha derivado en la colisión del derecho de propiedad intelectual que impulsa el Acuerdo sobre los Aspectos de los Derechos de Propiedad Intelectual relacionados con el Comercio (ADPIC) de la Organización Mundial del Comercio (OMC), con el derecho a la salud previsto en el Pacto Internacional de Derechos Económicos, Sociales y Culturales (PIDESC). Diversas controversias ventiladas en la OMC ilustran el enfrentamiento entre países con una poderosa industria farmacéutica y los intereses de países en desarrollo. Se concluye que las normas ADPIC-plus suscritas en tratados de libre comercio por países en desarrollo, que confieren al titular de la patente farmacéutica más derechos que los previstos en el propio Acuerdo sobre los ADPIC, son incompatibles con las obligaciones que asumen respecto del acceso a medicamentos esenciales en el marco del derecho a la salud del PIDESC.


The strengthening of pharmaceutical patent protection globally puts strains on access to essential medicines. According to the present paper, this process has led to the collision of the intellectual property rights adopted in the World Trade Organization (WTO) Trade-Related Aspects of Intellectual Property Rights (TRIPS) Agreement and the right to health stated in the International Covenant on Economic, Social and Cultural Rights (ICESCR). Several controversies disputed in the WTO illustrate the confrontation between countries with a powerful pharmaceutical industry and the interests of developing countries. It is concluded that the TRIPS-plus rules subscribed to by developing countries in free trade agreements which give the pharmaceutical patent holder more rights than those stipulated in the original TRIPS Agreement are incompatible with the obligations to provide access to essential medicines under the right to health of the ICESCR.


Assuntos
Animais , Cricetinae , Humanos , Camundongos , Vetores Genéticos , Poli(ADP-Ribose) Polimerases/genética , Interferência de RNA , DNA , Clonagem Molecular , Fibroblastos/enzimologia , Marcação de Genes , Camundongos Knockout , Poli(ADP-Ribose) Polimerases/análise , Pele/citologia
20.
Rev. méd. Chile ; 143(2): 175-182, feb. 2015. tab
Artigo em Espanhol | LILACS | ID: lil-742568

RESUMO

Background: In 2007, a Clinical-Case-Portfolio (CCP) was introduced as a new assessment instrument for fourth grade undergraduate medical students. Since then, several changes have been implemented such as reduction on the number of clinical cases, peer review and the introduction of virtual patient to the portfolio. Aim: To describe the virtual patient model incorporated to the CCP and assess the perception of this change and its effects on the performance of undergraduate students. Material and Methods: Virtual patients were implemented based on prototype clinical cases with specific syndromes. Students’ perceptions about CCP before and after the introduction of virtual patients were evaluated using a validated questionnaire that was answered voluntarily and anonymously. Results: Overall perception of CCP significantly improved after the incorporation of virtual patients (97.1 ± 24.9 and 111.3 ± 25.7 points; 57.8 and 66.2% respectively). The same improvements were observed for the domains “Student Learning”, “Organization and Evaluation”, “Teaching Methodology” and “Integration”. In both years, students obtained high grades in CCP evaluations. However CCP grades were not significantly correlated with integrated final grades. Conclusions: The incorporation of virtual patients improved undergraduate students’ perception of CCP.


Assuntos
Animais , Camundongos , Apoptose , Proteína Axina/metabolismo , Ativação Enzimática , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Fator de Indução de Apoptose/genética , Fator de Indução de Apoptose/metabolismo , Aurora Quinases , Linhagem Celular , Membrana Celular/metabolismo , Membrana Celular/fisiologia , Mitocôndrias/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , Imagem com Lapso de Tempo
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