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1.
Cell ; 137(3): 498-508, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19410546

RESUMO

DNA methylation is a conserved epigenetic mark in plants and mammals. In Arabidopsis, DNA methylation can be triggered by small interfering RNAs (siRNAs) through an RNA-directed DNA methylation (RdDM) pathway. Here, we report the identification of an RdDM effector, KTF1. Loss-of-function mutations in KTF1 reduce DNA methylation and release the silencing of RdDM target loci without abolishing the siRNA triggers. KTF1 has similarity to the transcription elongation factor SPT5 and contains a C-terminal extension rich in GW/WG repeats. KTF1 colocalizes with ARGONAUTE 4 (AGO4) in punctate nuclear foci and binds AGO4 and RNA transcripts. Our results suggest KTF1 as an adaptor protein that binds scaffold transcripts generated by Pol V and recruits AGO4 and AGO4-bound siRNAs to form an RdDM effector complex. The dual interaction of an effector protein with AGO and small RNA target transcripts may be a general feature of RNA-silencing effector complexes.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Metilação de DNA , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Argonautas , Sítios de Ligação , DNA de Plantas/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
2.
Hum Genomics ; 13(1): 1, 2019 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-30606250

RESUMO

BACKGROUND: Recent advances in semiconductor sequencing platform (SSP) have provided new methods for preimplantation genetic diagnosis/screening (PGD/S). The present study aimed to evaluate the applicability and efficiency of SSP in PGD/S. METHODS: The artificial positive single-cell-like DNAs and normal single-cell samples were chosen to test our semiconductor sequencing platform for preimplantation genetic diagnosis/screening (SSP-PGD/S) method with two widely used whole-genome amplification (WGA) kits. A total of 557 single blastomeres were collected from in vitro fertilization (IVF) couples, and their WGA products were processed and analyzed by our SSP-PGD/S method in comparison with array comparative genomic hybridization (array-CGH). RESULTS: Our SSP-PGD/S method indicated high compatibilities with two commercial WGA kits. For 557 single blastomeres, our method with four million reads in average could detect 24-chromosome aneuploidies as well as microdeletion/microduplication of the size over 4 Mb, providing 100% consistent conclusion with array-CGH method in the classification of whether it was transplantable. CONCLUSIONS: Our studies suggested that SSP-PGD/S represents a valuable alternative to array-CGH and brought PGD/S into a new era of more rapid, accurate, and economic.


Assuntos
Blastômeros/fisiologia , Diagnóstico Pré-Implantação/métodos , Sequenciamento Completo do Genoma/métodos , Aneuploidia , Blastômeros/citologia , Hibridização Genômica Comparativa , Variações do Número de Cópias de DNA , Feminino , Fertilização in vitro , Humanos , Masculino , Semicondutores , Aberrações dos Cromossomos Sexuais , Análise de Célula Única/instrumentação , Análise de Célula Única/métodos , Sequenciamento Completo do Genoma/instrumentação
3.
Am J Obstet Gynecol ; 222(2): 185.e1-185.e17, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31394068

RESUMO

BACKGROUND: Thalassemia is one of the most common monogenetic diseases in the south of China and Southeast Asia. Hemoglobin Bart's hydrops fetalis syndrome was caused by a homozygous Southeast Asian deletion (-/-) in the HBA gene. Few studies have proved the potential of screen for Bart's hydrops fetalis using fetal cell-free DNA. However, the number of cases is still relatively small. Clinical trials of large samples would be needed. OBJECTIVE: In this study, we aimed to develop a noninvasive method of target-captured sequencing and genotyping by the Bayesian method using cell-free fetal DNA to identify the fetal genotype in pregnant women who are at risk of having hemoglobin Bart hydrops fetalis in a large-scale study. STUDY DESIGN: In total, 192,173 couples from 30 hospitals were enrolled in our study and 878 couples were recruited, among whom both the pregnant women and their husbands were detected to be carriers of Southeast Asian type (-/αα) of α-thalassemia. Prenatal diagnosis was performed by chorionic villus sampling, amniocentesis, or cordocentesis using gap-polymerase chain reaction considered as the golden standard. RESULTS: As a result, we found that the sensitivity and specificity of our noninvasive method were 98.81% and 94.72%, respectively, in the training set as well as 100% and 99.31%, respectively, in the testing set. Moreover, our method could identify all of 885 maternal samples with the Southeast Asian carrier and 36 trisomy samples with 100% of sensitivity in T13, T18, and T21 and 99.89% (1 of 917) and 99.88% (1 of 888) of specificity in T18 and T21, respectively. CONCLUSION: Our method opens the possibility of early screening for maternal genotyping of α-thalassemia, fetal aneuploidies in chromosomes 13/18/21, and hemoglobin Bart hydrops fetalis detection in 1 tube of maternal plasma.


Assuntos
Hemoglobinas Anormais/genética , Hidropisia Fetal/diagnóstico , Amniocentese , Teorema de Bayes , Ácidos Nucleicos Livres , Amostra da Vilosidade Coriônica , Cordocentese , Síndrome de Down/diagnóstico , Feminino , Genótipo , Heterozigoto , Humanos , Hidropisia Fetal/genética , Teste Pré-Natal não Invasivo , Gravidez , Sensibilidade e Especificidade , Síndrome da Trissomia do Cromossomo 13/diagnóstico , Síndrome da Trissomía do Cromossomo 18/diagnóstico , Talassemia alfa/diagnóstico , Talassemia alfa/genética
4.
Proc Natl Acad Sci U S A ; 112(47): 14670-5, 2015 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-26554006

RESUMO

Noninvasive prenatal testing (NIPT) using sequencing of fetal cell-free DNA from maternal plasma has enabled accurate prenatal diagnosis of aneuploidy and become increasingly accepted in clinical practice. We investigated whether NIPT using semiconductor sequencing platform (SSP) could reliably detect subchromosomal deletions/duplications in women carrying high-risk fetuses. We first showed that increasing concentration of abnormal DNA and sequencing depth improved detection. Subsequently, we analyzed plasma from 1,456 pregnant women to develop a method for estimating fetal DNA concentration based on the size distribution of DNA fragments. Finally, we collected plasma from 1,476 pregnant women with fetal structural abnormalities detected on ultrasound who also underwent an invasive diagnostic procedure. We used SSP of maternal plasma DNA to detect subchromosomal abnormalities and validated our results with array comparative genomic hybridization (aCGH). With 3.5 million reads, SSP detected 56 of 78 (71.8%) subchromosomal abnormalities detected by aCGH. With increased sequencing depth up to 10 million reads and restriction of the size of abnormalities to more than 1 Mb, sensitivity improved to 69 of 73 (94.5%). Of 55 false-positive samples, 35 were caused by deletions/duplications present in maternal DNA, indicating the necessity of a validation test to exclude maternal karyotype abnormalities. This study shows that detection of fetal subchromosomal abnormalities is a viable extension of NIPT based on SSP. Although we focused on the application of cell-free DNA sequencing for NIPT, we believe that this method has broader applications for genetic diagnosis, such as analysis of circulating tumor DNA for detection of cancer.


Assuntos
Aberrações Cromossômicas/embriologia , DNA/sangue , Feto/anormalidades , Diagnóstico Pré-Natal/métodos , Semicondutores , Análise de Sequência de DNA/métodos , Sistema Livre de Células , Deleção Cromossômica , Duplicação Cromossômica , Hibridização Genômica Comparativa , Feminino , Humanos , Peso Molecular , Gravidez
5.
Proc Natl Acad Sci U S A ; 111(20): 7415-20, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24799683

RESUMO

Massively parallel sequencing (MPS) of cell-free fetal DNA from maternal plasma has revolutionized our ability to perform noninvasive prenatal diagnosis. This approach avoids the risk of fetal loss associated with more invasive diagnostic procedures. The present study developed an effective method for noninvasive prenatal diagnosis of common chromosomal aneuploidies using a benchtop semiconductor sequencing platform (SSP), which relies on the MPS platform but offers advantages over existing noninvasive screening techniques. A total of 2,275 pregnant subjects was included in the study; of these, 515 subjects who had full karyotyping results were used in a retrospective analysis, and 1,760 subjects without karyotyping were analyzed in a prospective study. In the retrospective study, all 55 fetal trisomy 21 cases were identified using the SSP with a sensitivity and specificity of 99.94% and 99.46%, respectively. The SSP also detected 16 trisomy 18 cases with 100% sensitivity and 99.24% specificity and 3 trisomy 13 cases with 100% sensitivity and 100% specificity. Furthermore, 15 fetuses with sex chromosome aneuploidies (10 45,X, 2 47,XYY, 2 47,XXX, and 1 47,XXY) were detected. In the prospective study, nine fetuses with trisomy 21, three with trisomy 18, three with trisomy 13, and one with 45,X were detected. To our knowledge, this is the first large-scale clinical study to systematically identify chromosomal aneuploidies based on cell-free fetal DNA using the SSP and provides an effective strategy for large-scale noninvasive screening for chromosomal aneuploidies in a clinical setting.


Assuntos
Aneuploidia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Diagnóstico Pré-Natal/métodos , Adulto , Transtornos Cromossômicos/diagnóstico , Cromossomos Humanos Par 13 , Cromossomos Humanos Par 18 , Análise Custo-Benefício , Síndrome de Down/diagnóstico , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Humanos , Cariotipagem , Masculino , Gravidez , Estudos Prospectivos , Estudos Retrospectivos , Semicondutores , Sensibilidade e Especificidade , Trissomia/diagnóstico , Síndrome da Trissomia do Cromossomo 13 , Síndrome da Trissomía do Cromossomo 18
6.
Genes Dev ; 23(23): 2717-22, 2009 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19903758

RESUMO

RNA-directed DNA methylation (RdDM) is a conserved mechanism for epigenetic silencing of transposons and other repetitive elements. We report that the rdm4 (RNA-directed DNA Methylation4) mutation not only impairs RdDM, but also causes pleiotropic developmental defects in Arabidopsis. Both RNA polymerase II (Pol II)- and Pol V-dependent transcripts are affected in the rdm4 mutant. RDM4 encodes a novel protein that is conserved from yeast to humans and interacts with Pol II and Pol V in plants. Our results suggest that RDM4 functions in epigenetic regulation and plant development by serving as a transcriptional regulator for RNA Pol V and Pol II, respectively.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Metilação de DNA , DNA de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , RNA de Plantas/metabolismo , Arabidopsis/enzimologia , Arabidopsis/genética , Sequência Conservada , RNA Polimerases Dirigidas por DNA/metabolismo , Inativação Gênica/fisiologia , Humanos , Mutação , Fenótipo
7.
Nature ; 465(7294): 106-9, 2010 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-20410883

RESUMO

DNA methylation is an important epigenetic mark in many eukaryotes. In plants, 24-nucleotide small interfering RNAs (siRNAs) bound to the effector protein, Argonaute 4 (AGO4), can direct de novo DNA methylation by the methyltransferase DRM2 (refs 2, 4-6). Here we report a new regulator of RNA-directed DNA methylation (RdDM) in Arabidopsis: RDM1. Loss-of-function mutations in the RDM1 gene impair the accumulation of 24-nucleotide siRNAs, reduce DNA methylation, and release transcriptional gene silencing at RdDM target loci. RDM1 encodes a small protein that seems to bind single-stranded methyl DNA, and associates and co-localizes with RNA polymerase II (Pol II, also known as NRPB), AGO4 and DRM2 in the nucleus. Our results indicate that RDM1 is a component of the RdDM effector complex and may have a role in linking siRNA production with pre-existing or de novo cytosine methylation. Our results also indicate that, although RDM1 and Pol V (also known as NRPE) may function together at some RdDM target sites in the peri-nucleolar siRNA processing centre, Pol II rather than Pol V is associated with the RdDM effector complex at target sites in the nucleoplasm.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , RNA Polimerase II/metabolismo , RNA de Plantas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas Argonautas , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica de Plantas , Inativação Gênica/fisiologia , Metiltransferases/metabolismo , Mutação
8.
Tumour Biol ; 36(7): 5679-85, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25764087

RESUMO

Surgery, chemotherapy, and radiotherapy have presented with the ability of killing tumor cells, as well as damaging the immune function, which can be corrected by the immunotherapy. The purpose of this perspective cohort study was to evaluate the efficacy of postoperative immunotherapies of tumor lysate-loaded dendritic cells (DC), in vitro DC-activated T (DC-AT), and activated T cells (ATC) combined with chemotherapy on the survival of patients with operable colorectal cancer. A total of 253 patients with primary colorectal cancer resection including 181 patients receiving postoperative simple chemotherapy (control group) and 72 patients receiving immunotherapies of DC, DC-AT, and ATC combined with chemotherapy during the corresponding period (immunotherapy group) were enrolled in this perspective cohort study. The survival of these patients was analyzed. The immunotherapy group presented a higher 5-year overall survival rate than the control group (75.63 vs 67.81 %, P = 0.035), as well as 3-year overall survival rate (87.07 vs 74.80 %, P = 0.045). For patients with advanced cancer (TNM stages III and IV), immunotherapy significantly promotes mean survival than control subjects (59.74 ± 3.21 vs 49.99 ± 2.54 years, P = 0.034). Patients who received more than three cycles of immunotherapies had a higher 5-year overall survival rate than those with less than three cycles (82.10 vs 69.90 %, P = 0.035). No serious adverse effect was observed in the immunotherapy group. Postoperative immunotherapies with DC, DC-AT, and ATC combination can promote the survival of patients with operable colorectal cancer (Clinical Trials, ChiCTR-OCH-12002610).


Assuntos
Neoplasias Colorretais/imunologia , Células Dendríticas/imunologia , Imunoterapia , Linfócitos T/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Terapia Combinada , Células Matadoras Induzidas por Citocinas/imunologia , Células Dendríticas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Taxa de Sobrevida
9.
Dig Surg ; 32(6): 433-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26402444

RESUMO

BACKGROUND: CD8+ central memory T cells (CD8+ Tcm) have superior roles in antitumor immunity. The purpose of this study was to detect CD8+ Tcm in the peripheral blood of patients with pancreatic adenocarcinoma and to analyze its clinic significance. METHODS: Seventy two patients with primary pancreatic adenocarcinoma who underwent curative operation were enrolled. The percentage and absolute count of CD8+ Tcm in the peripheral blood of patients were analyzed through flow cytometry and the multiplatform predicate method, respectively, and these values were compared to those of the healthy control. The correlation between CD8+ Tcm and survival was analyzed by the Kaplan-Meier with log-rank test and Cox's regression methods, respectively. RESULTS: The percentage of CD8+ Tcm from pancreatic adenocarcinoma was higher than the healthy control (16.79 ± 9.43% vs. 11.41 ± 4.67%, p = 0.028), which also had a relationship with the lymph node status. Patients with high-level CD8+ Tcm had a significantly higher median survival than those with low CD8+ Tcm (18 vs. 12 months, p = 0.004); a similar result was obtained in absolute CD8+ Tcm count. It was revealed in multivariate analysis that both percentage and absolute count of CD8+ Tcm was an independent prognostic factor for overall survival. CONCLUSIONS: CD8+ Tcm can be considered an independent prognostic factor for operable pancreatic adenocarcinoma, which was also associated with the lymph nodes metastasis.


Assuntos
Adenocarcinoma/sangue , Adenocarcinoma/secundário , Linfócitos T CD8-Positivos/imunologia , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/patologia , Adenocarcinoma/mortalidade , Adenocarcinoma/cirurgia , Feminino , Humanos , Imunidade Celular , Memória Imunológica , Metástase Linfática , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/cirurgia , Período Pré-Operatório , Prognóstico , Taxa de Sobrevida
10.
Plant Mol Biol ; 84(6): 707-18, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24337866

RESUMO

Saussurea involucrata Kar. et Kir. is a hardy dicotyledonous plant capable of tolerating severe abiotic stress conditions. In a previous study, we created a cDNA library to determine what factors are associated with the cold acclimation response in S. involucrata. From this, a full-length cDNA of a dehydrin-like gene (SiDhn2) was obtained by RT-PCR. The SiDhn2 gene was characterized in this study. The full-length SiDhn2 cDNA comprised 693 bp containing an open reading frame of 345 bp specifying a protein of 115 amino acids. An alignment of the deduced amino acid sequence showed that SiDhn2 shared 55 % identity with two Brassica dehydrins. Agrobacterium tumefaciens was used to transform RD29A:SiDhn2 and 35S:SiDhn2 constructs into tobacco to investigate the germination and resistance to freezing and drought stress of transgenic plants. The RD29A:SiDhn2 transgenic plants showed greater resistance to freezing and drought stress than 35S:SiDhn2 transgenic plants or the wild-type. This study demonstrates that SiDhn2 confers cold hardiness and drought resistance, and may be a candidate resistance gene for genetic improvement of crops to increase stress resistance.


Assuntos
Aclimatação , Regulação da Expressão Gênica , Proteínas de Plantas/genética , Saussurea/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , DNA de Plantas/química , DNA de Plantas/genética , Secas , Congelamento , Biblioteca Gênica , Germinação , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Saussurea/fisiologia , Alinhamento de Sequência , Estresse Fisiológico , Nicotiana/genética , Nicotiana/fisiologia
11.
Toxicol Appl Pharmacol ; 267(2): 167-73, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23276654

RESUMO

In the present study, we aimed to investigate the immunosuppressive activity of vaticaffinol, a resveratrol tetramer isolated from Vatica mangachapoi, on T lymphocytes both in vitro and in vivo, and further explored its potential molecular mechanism. Resveratrol had a wide spectrum of healthy beneficial effects with multiple targets. Interestingly, its tetramer, vaticaffinol, exerted more intensive immunosuppressive activity than resveratrol. Vaticaffinol significantly inhibited T cells proliferation activated by concanavalin A (Con A) or anti-CD3 plus anti-CD28 in a dose- and time-dependent manner. It also induced Con A-activated T cells undergoing apoptosis through mitochondrial pathway. Moreover, this compound prevented cells from entering S phase and G2/M phase during T cells activation. In addition, vaticaffinol inhibited ERK and AKT signaling pathways in Con A-activated T cells. Furthermore, vaticaffinol significantly ameliorated ear swelling in a mouse model of picryl chloride-induced ear contact dermatitis in vivo. In most of the aforementioned experiments, however, resveratrol had only slight effects on the inhibition of T lymphocytes compared with vaticaffinol. Taken together, our findings suggest that vaticaffinol exerts more preferable immunosuppressive activity than its precursor resveratrol both in vitro and in vivo by affecting multiple targets against activated T cells.


Assuntos
Imunossupressores/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Estilbenos/química , Estilbenos/farmacologia , Linfócitos T/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Dermatite de Contato/tratamento farmacológico , Feminino , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Resveratrol
12.
Materials (Basel) ; 15(15)2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35955358

RESUMO

Volcanic soil is a special soil that is well-known for its distinctive texture, vesicular nature, and particle fragility. The fragility characteristic of volcanic soil is the main factor affecting the foundation stability in road engineering. This study focuses on the mechanical properties and particle crushing characteristics of volcanic soil retrieved from Northeast China. A series of triaxial consolidation and drainage shear tests are performed on volcanic coarse-grained soil (5 mm > d > 0.075 mm) under different initial relative densities and effective confining pressures. Results show the peak friction angle of volcanic soil significantly decreases with the increase of confining pressure. The particle crushing degree of volcanic soil increases with the increase of confining pressure, particle size, and relative density. The relative breakage rate of the same particle size group has a good linear relationship with a fractal dimension. Moreover, for the same particle size, the relationship between plastic work and relative breakage rate can be fitted by a power function, which is not significantly affected by relative density or effective confining pressure. From an engineering view, in addition to increasing the compaction degree of volcanic soil, volcanic soil with fine particles used as a roadbed filler can significantly reduce the deformation of the roadbed and improve the bearing capacity of the foundation.

13.
Bioorg Med Chem ; 19(10): 3096-104, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21530276

RESUMO

Inhibition of the excessive NO production has been recognized as a potential means for the treatment of rheumatoid arthritis (RA). In order to discover more potent inhibitors and explore the preliminary structure activity relationship, a series of unique stereodimers of sinomenine analogues were designed and synthesized. Their inhibitory activity on NO production and cytotoxicity were evaluated using LPS-activated murine macrophages RAW264.7 assay and MTT method, respectively. Among these compounds, 1a, 2, 2a, 2b, and 4 showed potent inhibitory activity on NO production without obvious cytotoxicity. Furthermore, 2, 2a, and 2b significantly suppressed mRNA expression of iNOS. Interestingly, (S)-dimers displayed a better bioactivity than (R)-dimers. These compounds may sever as lead candidates in the development of novel therapeutic drugs for RA treatment.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Morfinanos/química , Morfinanos/farmacologia , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/metabolismo , Animais , Artrite Reumatoide/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dimerização , Expressão Gênica/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Morfinanos/síntese química , Óxido Nítrico Sintase Tipo II/genética , RNA Mensageiro/genética , Estereoisomerismo
14.
J Appl Toxicol ; 31(2): 164-72, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20865757

RESUMO

This research focused on a novel 7-azaisoindigo derivative [namely N(1)-(n-butyl)-7-azaisoindigo, 7-AI-b], and investigated its molecular antitumor mechanism by exploring the means of cell death and the effects on mitochondrial function. 7-AI-b inhibited cancer cell proliferation in a dose- and time-dependent way. The morphological and nuclei changes in H(2) B-GFP-labeled HeLa cells were observed using a live cell system. The results suggested that cell death induced by 7-AI-b is closely related to apoptosis. 7-AI-b induced release of cytochrome C from mitochondria to cytosol and activation of caspase-3, showing that the apoptosis is mediated by the mitochondrial pathway. Furthermore, our data indicated that 7-AI-b triggers apoptosis through reactive oxygen species (ROS): cellular ROS levels were increased after 3 h exposure of 7-AI-b, which was reversed by the ROS scavenger N-acetyl-L-cysteine. As a consequence, 7-AI-b-mediated cell death, mitochondrial transmembrane potential collapse and ATP level were partly blocked by N-acetyl-L-cysteine. Further study showed that 7-AI-b could induce mitochondrial dysfunction: collapse of the mitochondrial transmembrane potential and reduction of intracellular ATP level. In summary, the novel synthesized 7-AI-b was demonstrated to be effective in killing cancer cells via an ROS-promoted and mitochondria- and caspase-dependent apoptotic pathway.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Indóis/farmacologia , Mitocôndrias/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Acetilcisteína/farmacologia , Trifosfato de Adenosina/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Concentração Osmolar , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo
15.
Chin J Nat Med ; 18(3): 186-195, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32245588

RESUMO

Alcoholic liver disease (ALD) has become one of the leading causes of death in the world. Berbamine (BM), a natural product mainly derived from Berberis vulgaris L, possesses multiple bioactivities as a traditional medicine. However, the protective effect of BM on ALD remains unknown. In this study, we investigated the effect of BM on ethanol-induced hepatic injury in mice and its underlying mechanism. It was shown that BM at 0.3125-40 µmol·L-1had no effect on macrophages and hepatocytes proliferation. BM at 5-20 µmol·L-1 significantly inhibited lipopolysaccharide (LPS) or acetate-induced IL-1ß and IL-6 mRNA expression in RAW264.7 cells. Moreover, BM treatment significantly inhibited LPS-induced p65 and STAT3 phosphorylation in RAW264.7 cells. Hepatic histopathology analysis showed that inflammatory cells infiltration and lipid accumulation were suppressed by 25 and 50 mg·kg-1 BM administration in ethanol-induced hepatic injury mouse model. Meanwhile, BM treatment significantly inhibited serum ALT and AST levels in ethanol-fed mice. Oil red O staining results showed that BM administration ameliorated hepatic lipid accumulation in ethanol-fed mice. Preventions of ethanol-induced hepatic injury by BM were reflected by markedly decreased serum and hepatic triglyceride (TG) and total cholesterol (TC) contents. Real-time PCR results showed that BM treatment significantly inhibited pro-inflammatory cytokines mRNA expression in ethanol-fed mouse liver. Remarkably, the mechanism of action of BM was related to the reduction of ethanol-induced NF-κB and STAT3 phosphorylation levels in liver. In addition, BM treatment significantly inhibited ERK phosphorylation but not JNK and p38 of MAPK pathway. Taken together, our results demonstrate a beneficial effect of BM on ethanol-induced liver injury via a mechanism associated with inactivation of NF-κB, STAT3 and ERK pathway, which gives insight into the further evaluation of the therapeutic potential of BM for ALD.


Assuntos
Benzilisoquinolinas/farmacologia , Doença Hepática Crônica Induzida por Substâncias e Drogas/tratamento farmacológico , Inflamação/tratamento farmacológico , Fígado/efeitos dos fármacos , Animais , Colesterol/sangue , Citocinas/metabolismo , Etanol/efeitos adversos , Feminino , Hepatócitos/efeitos dos fármacos , Metabolismo dos Lipídeos , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Células RAW 264.7 , Fator de Transcrição STAT3/metabolismo , Triglicerídeos/sangue
16.
PLoS Negl Trop Dis ; 14(10): e0008643, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33044969

RESUMO

BACKGROUND: Clonorchis sinensis, a fluke dwelling in the intrahepatic bile ducts causes clonorchiasis, which affect about 15 million people wide-distributed in eastern Asia. During C. sinensis infection, worm-host interaction results in activation of patterns recognition receptors (PRRs) such as Toll-like receptors (TLRs) and further triggers immune responses, which determines the outcome of the infection. However, the mechanisms by which pathogen-associated molecules patterns from C. sinensis interact with TLRs were poorly understood. In the present study, we assumed that the molecules from C. sinensis may regulate host immune responses via TLR2 signaling pathway. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we have identified a ~34 kDa CsHscB from C. sinensis which physically bound with TLR2 as demonstrated by molecular docking and pull-down assay. We also found that recombinant CsHscB (rCsHscB) potently activates macrophage to express various proteins including TLR2, CD80, MHCII, and cytokines like IL-6, TNF-α, and IL-10, but rCsHscB failed to induce IL-10 in macrophages from Tlr2-/- mice. Moreover, ERK1/2 activation was required for rCsHscB-induced IL-10 production in macrophages. In vivo study revealed that rCsHscB triggered a high production of IL-10 in the wild-type (WT) but not in Tlr2-/- mice. Consistently, the phosphorylation of ERK1/2 was also attenuated in Tlr2-/- mice compared to the WT mice, after the treatment with rCsHscB. CONCLUSIONS/SIGNIFICANCE: Our data thus demonstrate that rCsHscB from C. sinensis interacts with TLR2 to be endowed with immune regulatory activities, and may have some therapeutic implications in future beyond parasitology.


Assuntos
Clonorquíase/imunologia , Clonorchis sinensis/imunologia , Proteínas de Choque Térmico/metabolismo , Interleucina-10/metabolismo , Animais , Clonorquíase/parasitologia , Proteínas de Helminto/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Simulação de Acoplamento Molecular , Proteínas Recombinantes , Receptor 2 Toll-Like
17.
J Appl Toxicol ; 29(6): 489-95, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19391119

RESUMO

Eight novel oxdiazolo[3,4-d]pyrimidine nucleoside derivatives (I-VIII) were synthesized to investigate their anti-tumor effects and possible mechanisms. Four human cancer cell lines including Hela, ECA109, HepG2 and A459 cells were used. Compounds VI and VIII showed significant inhibition on cancer cell proliferation by MTT assay and IC50 values were around 30-70 micromol l(-1). Both compounds could release nitric oxide (NO), led to a significant intracellular free Ca2+ overloading and resulted in mitochondrial dysfunction, showing a decrease in mitochondrial membrane potential in HepG2 cells in a dose-dependent manner. Furthermore, compound VIII induced obvious DNA damage on HepG2 cells. These data indicate that compounds VI and VIII are two active antitumor compounds, and both DNA damage and mitochondrial dysfunction are involved in the mechanisms underlying oxadiazolo[3,4-d]pyrimidine nucleoside derivative-induced cancer cell death, which might also be related to the released NO.


Assuntos
Apoptose/efeitos dos fármacos , Dano ao DNA , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Nucleosídeos de Pirimidina/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Formazans/metabolismo , Células HeLa , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Oxidiazóis/química , Oxidiazóis/metabolismo , Oxidiazóis/farmacologia , Nucleosídeos de Pirimidina/química , Nucleosídeos de Pirimidina/metabolismo , Sais de Tetrazólio/metabolismo , Fatores de Tempo
18.
Chin J Nat Med ; 17(7): 525-534, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31514984

RESUMO

This study aimed to investigate the mechanisms of Yu-Ping-Feng-San (YPFS) on attenuating allergic inflammation in the initial stage of atopic dermatitis (AD). AD mouse model was established with fluorescein isothiocyanate (FITC) sensitization and elicitation. Epithelial barrier structure was observed with transmission electron microscope. The populations of dendritic cells (DCs) and group 2 innate lymphoid cells (ILC2s) were detected by flow cytometry. Human immortalized keratinocyte (HaCaT) cells were stimulated with Poly(I:C)/TNF-α in vitro to assessthymic stromal lymphopoietin (TSLP), interleukin (IL)-33 and nuclear factor-κB (NF-κB) levels or expressions by immunofluorescence, enzyme linked immunosorbent assay (ELISA) and western blot. In the initial stage of AD, ear swelling and infiltration of inflammatory cells in ear tissues were markedly attenuated with YPFS treatments. The damaged structures of ear epithelium and the increased levels of Th2-cytokines induced by FITC were significantly rescued in YPFS-treated mice. The production of pro-allergic cytokines, TSLP and IL-33, as well as the cell populations of their target cells DCs and ILC2s were decreased in AD model, respectively. Likewise, the levels of TSLP and IL-33 in Poly(I:C)/TNF-α-stimulated HaCaT cells showed the same results. Lower levels of p-NF-κB were detected with YPFS treatment, and the expressions of TSLP and IL-33 could be further decreased with inhibiting of NF-κB. Therefore, YPFS attenuates allergic inflammation in the initial stage of AD probably through regulating NF-κB-TSLP/IL-33 pathway, which may provide a novel effective target for the prevention and treatment of allergic diseases.


Assuntos
Antialérgicos/uso terapêutico , Citocinas/metabolismo , Dermatite Atópica/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Inflamação/prevenção & controle , Animais , Antialérgicos/farmacologia , Linhagem Celular , Células Dendríticas/patologia , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/metabolismo , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Células Epiteliais/metabolismo , Fluoresceína-5-Isotiocianato/toxicidade , Inflamação/metabolismo , Inflamação/patologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Linfócitos/metabolismo , Linfócitos/patologia , Camundongos Endogâmicos BALB C , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
19.
Mol Cytogenet ; 11: 37, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29946361

RESUMO

BACKGROUND: Non-invasive prenatal testing (NIPT) evaluates circulating cell-free DNA (cfDNA) and has been widely applied, with highly accurate results for detecting foetal trisomies 21, 18 and 13. Recently, increasing attention has been paid to the clinical application of the non-invasive detection of foetal sub-chromosomal duplications and deletions beyond common aneuploidies. CASE PRESENTATION: A 32-year-old healthy pregnant woman was referred to the Medical Genetic Centre of Ganzhou Maternal and Child Health Care Hospital. As routine practice, ultrasound examination at a gestational age of 16 weeks showed that the foetus is normal. To avoid invasive prenatal diagnosis procedures, an NIPT was offered to further screen for common foetal chromosomal abnormalities. The result showed that there was an approximately 50.94 Mb duplication in p11.32-q21.2 of chromosome 18 and an approximately 58.46 Mb deletion in p22.33-p11.1 of chromosome X. In addition, the chromosome karyotypes of the parents and foetus were also analysed. Chromosome karyotype analysis results showed that foetal karyotype was 46,X,der(18), the maternal karyotype was 46,XX,t(X;18)(q13;q21.3), and the paternal karyotype revealed no obvious abnormality. CONCLUSION: In this case, we successfully detected a healthy pregnant woman with balanced translocation X;18(q13;q21.3) and described the foetal karyotype as 46,X,der(18)t(X;18)(q11;q21.1)mat. Our report illustrated these cases which present complex X;autosome balance translocation and X;autosome unbalance translocation which may contribute to severe clinical phenotypes. In addition, our report also proved that the interruption of genes in the Xq critical region is not only reason of primary infertility. Finally, we prompted that NIPT might play a role in the first trimester screening of sub-chromosomal rearrangement.

20.
Mol Neurobiol ; 55(5): 3999-4008, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28567666

RESUMO

As a multi-stage disorder, Alzheimer's disease (AD) is quickly becoming one of the most prevalent neurodegenerative diseases worldwide. Thus, a non-invasive, serum-based diagnostic platform is eagerly awaited. The goal of this study was to identify a serum-based biomarker panel using a predictive protein-based algorithm that is able to confidently distinguish AD patients from control subjects. One hundred and fifty-six patients with AD and the same number of gender- and age-matched control participants with standardized clinical assessments and neuroimaging measures were evaluated. Serum proteins of interest were quantified using a magnetic bead-based immunofluorescent assay, and a total of 33 analytes were examined. All of the subjects were then randomized into a training set containing 70% of the total samples and a validation set containing 30%, with each containing an equal number of AD and normal samples. Logistic regression and random forest analyses were then applied to develop a desirable algorithm for AD detection. The random forest method was found to generate a more robust predictive model than the logistic regression analysis. Furthermore, an eight-protein-based algorithm was found to be the most robust with a sensitivity of 97.7%, specificity of 88.6%, and AUC of 99%. Our study developed a novel eight-protein biomarker panel that can be used to distinguish AD and control multi-source candidates regardless of age. It is hoped that these results provide further insight into the applicability of serum-based screening methods and contribute to the development of lower-cost, less invasive methods for diagnosing AD and monitoring progression.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Proteínas Sanguíneas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Área Sob a Curva , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes
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