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1.
Nature ; 620(7975): 904-910, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37558880

RESUMO

Arrestins have pivotal roles in regulating G protein-coupled receptor (GPCR) signalling by desensitizing G protein activation and mediating receptor internalization1,2. It has been proposed that the arrestin binds to the receptor in two different conformations, 'tail' and 'core', which were suggested to govern distinct processes of receptor signalling and trafficking3,4. However, little structural information is available for the tail engagement of the arrestins. Here we report two structures of the glucagon receptor (GCGR) bound to ß-arrestin 1 (ßarr1) in glucagon-bound and ligand-free states. These structures reveal a receptor tail-engaged binding mode of ßarr1 with many unique features, to our knowledge, not previously observed. Helix VIII, instead of the receptor core, has a major role in accommodating ßarr1 by forming extensive interactions with the central crest of ßarr1. The tail-binding pose is further defined by a close proximity between the ßarr1 C-edge and the receptor helical bundle, and stabilized by a phosphoinositide derivative that bridges ßarr1 with helices I and VIII of GCGR. Lacking any contact with the arrestin, the receptor core is in an inactive state and loosely binds to glucagon. Further functional studies suggest that the tail conformation of GCGR-ßarr governs ßarr recruitment at the plasma membrane and endocytosis of GCGR, and provides a molecular basis for the receptor forming a super-complex simultaneously with G protein and ßarr to promote sustained signalling within endosomes. These findings extend our knowledge about the arrestin-mediated modulation of GPCR functionalities.


Assuntos
Receptores de Glucagon , beta-Arrestina 1 , beta-Arrestina 1/química , beta-Arrestina 1/metabolismo , Membrana Celular/metabolismo , Endocitose , Endossomos/metabolismo , Glucagon/metabolismo , Proteínas Heterotriméricas de Ligação ao GTP/metabolismo , Ligantes , Fosfatidilinositóis/metabolismo , Receptores de Glucagon/química , Receptores de Glucagon/metabolismo , Ligação Proteica
2.
J Chem Inf Model ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38920405

RESUMO

Artificial intelligence (AI)-aided drug design has demonstrated unprecedented effects on modern drug discovery, but there is still an urgent need for user-friendly interfaces that bridge the gap between these sophisticated tools and scientists, particularly those who are less computer savvy. Herein, we present DrugFlow, an AI-driven one-stop platform that offers a clean, convenient, and cloud-based interface to streamline early drug discovery workflows. By seamlessly integrating a range of innovative AI algorithms, covering molecular docking, quantitative structure-activity relationship modeling, molecular generation, ADMET (absorption, distribution, metabolism, excretion and toxicity) prediction, and virtual screening, DrugFlow can offer effective AI solutions for almost all crucial stages in early drug discovery, including hit identification and hit/lead optimization. We hope that the platform can provide sufficiently valuable guidance to aid real-word drug design and discovery. The platform is available at https://drugflow.com.

3.
Drug Resist Updat ; 69: 100973, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37148599

RESUMO

Sequence type 235 (ST235) Pseudomonas aeruginosa, harboring so-called international, high-risk, or widespread clones, is associated with relatively high morbidity and mortality, partly due to multiantibiotic and high-level antibiotic resistance. Treatment of infections caused by such strains with ceftazidime-avibactam (CZA) is often successful. However, CZA resistance in carbapenem-resistant P. aeruginosa (CRPA) strains has been consistently reported with the increasing use of this drug. Likewise, we identified thirty-seven CZA-resistant ST235 P. aeruginosa strains from among 872 CRPA isolates. A total of 10.8% of the ST235 CRPA strains were resistant to CZA. Site-directed mutagenesis, cloning, expression, and whole-genome sequencing analysis revealed that overexpression of blaGES-1, which was carried in a class 1 integron of the complex transposon Tn6584, occurred due to a strong promoter, contributing to CZA resistance. Moreover, such overexpression of blaGES-1 combined with an efflux pump resulted in high-level resistance to CZA, considerably reducing the therapeutic options available for treating infections caused by ST235 CRPA. Considering the widespread presence of ST235 P. aeruginosa strains, clinicians should be aware of the risk of CZA resistance development in high-risk ST235 P. aeruginosa. Surveillance initiatives for preventing further dissemination of high-risk ST235 CRPA isolates with CZA resistance are essential.


Assuntos
Farmacorresistência Bacteriana Múltipla , Pseudomonas aeruginosa , Antibacterianos/farmacologia , beta-Lactamases/genética , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Integrons/genética , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/genética , Infecções por Pseudomonas
4.
Antimicrob Agents Chemother ; 67(11): e0067523, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37819082

RESUMO

Pseudomonas aeruginosa high-risk clones pose severe threats to public health. Here, we characterize the imipenem/relebactam (IR) resistance mechanisms in P. aeruginosa high-risk clones sequence type 235 (ST235) and ST463 in China. Minimum inhibitory concentrations (MICs) were determined, and Illumina short-read sequencing was performed for 1,168 clinical carbapenem-resistant P. aeruginosa (CRPA) isolates. The gene copy number and expression level were analyzed by Illumina sequencing depth and reverse transcription-quantitative PCR, respectively. Resistance conferred by bla GES-5 was evaluated by cloning experiments. ST463 and ST235 accounted for 9.8% (115/1,168) and 4.5% (53/1,168) of total isolates, respectively, and showed high frequencies of extensively drug-resistant and difficult-to-treat resistant phenotypes. The overall IR-resistant rate in CRPA was 21.0% (245/1,168). However, the IR resistance rate was 81.7% (94/115) in ST463-PA and 52.8% (28/53) in ST235-PA. Of the ST463 isolates, 92.2% (106/115) were Klebsiella pneumoniae carbapenemase-producing P. aeruginosa (KPC-PA), and all 94 IR-resistant ST463-PA produced KPC-2. Compared to IR-susceptible ST463 KPC-2-PA, IR-resistant ST463 KPC-2-PA exhibited significantly higher bla KPC-2 copy numbers and expression levels. In ST463 KPC-2-PA, 16 mg/L relebactam resulted in additional fourfold reductions in imipenem MIC50/90 values compared to 4 mg/L relebactam. In ST235, 1.9% (1/53) carried bla IMP carbapenemase and 54.7% (29/53) carried bla GES carbapenemase. Other than the IMP producer, all 27 IR-resistant ST235-PA produced GES-5. Cloning experiments revealed that imipenem resistance in bla GES-5-carrying PAO1 transformants was generally unaffected by relebactam. In conclusion, IR-resistant CRPA isolates in China were mainly distributed in P. aeruginosa high-risk clones ST463 and ST235. The major underlying IR resistance mechanisms were bla KPC-2 overexpression and bla GES-5 carriage.


Assuntos
Infecções por Pseudomonas , Pseudomonas aeruginosa , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , beta-Lactamases/metabolismo , Carbapenêmicos/uso terapêutico , Células Clonais/metabolismo , Imipenem/farmacologia , Imipenem/uso terapêutico , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Infecções por Pseudomonas/tratamento farmacológico
5.
Pacing Clin Electrophysiol ; 46(9): 1035-1048, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37573146

RESUMO

Transcatheter radiofrequency ablation has been widely introduced for the treatment of tachyarrhythmias. The demand for catheter ablation continues to grow rapidly as the level of recommendation for catheter ablation. Traditional catheter ablation is performed under the guidance of X-rays. X-rays can help display the heart contour and catheter position, but the radiobiological effects caused by ionizing radiation and the occupational injuries worn caused by medical staff wearing heavy protective equipment cannot be ignored. Three-dimensional mapping system and intracardiac echocardiography can provide detailed anatomical and electrical information during cardiac electrophysiological study and ablation procedure, and can also greatly reduce or avoid the use of X-rays. In recent years, fluoroless catheter ablation technique has been well demonstrated for most arrhythmic diseases. Several centers have reported performing procedures in a purposefully designed fluoroless electrophysiology catheterization laboratory (EP Lab) without fixed digital subtraction angiography equipment. In view of the lack of relevant standardized configurations and operating procedures, this expert task force has written this consensus statement in combination with relevant research and experience from China and abroad, with the aim of providing guidance for hospitals (institutions) and physicians intending to build a fluoroless cardiac EP Lab, implement relevant technologies, promote the standardized construction of the fluoroless cardiac EP Lab.


Assuntos
Ablação por Cateter , Técnicas Eletrofisiológicas Cardíacas , Cirurgia Assistida por Computador , Humanos , Eletrofisiologia Cardíaca , Ablação por Cateter/métodos , Técnicas Eletrofisiológicas Cardíacas/métodos , Cirurgia Assistida por Computador/métodos , Resultado do Tratamento
6.
Arch Toxicol ; 97(2): 561-580, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36329302

RESUMO

IL-17 is closely associated with inflammation in intrahepatic cholestasis (IHC). Targeting IL-17 ameliorates IHC in mice. Invariant natural killer T (iNKT) cells are predominantly enriched in the liver and they mediate drug-induced liver injury through their secreted cytokines. However, whether iNKT17 cells are involved in ethinylestradiol (EE)-induced IHC remains unclear. In the present study, the administration of EE (10 mg/kg in vivo and 6.25 µM in vitro) promoted the activation and expansion of iNKT17 cells, which contributed to a novel hepatic iNKT17/Treg imbalance. iNKT cell-deficient Jα18-/- mice and the RORγt inhibitor digoxin (20 µg) alleviated EE-induced cholestatic hepatotoxicity and downregulated the IL-17 signalling pathway. In contrast, the co-administration of EE with recombinant IL-17 (1 µg) to Jα18-/- mice induced cholestatic hepatotoxicity and increased the infiltration of hepatic neutrophils and monocytes. Importantly, the administration of IL-17-/- iNKT cells (3.5 × 105) to Jα18-/- mice resulted in the attenuation of hepatotoxicity and the recruitment of fewer hepatic neutrophils and monocytes than the adoptive transfer of wild-type iNKT cells. These results indicated that iNKT17 cells could exert pathogenic effects. The recruitment and activation of iNKT17 cells could be attributed to the high level of CXCR3 expression on their surface. CXCL10 deficiency ameliorated EE-induced cholestatic liver damage, reduced hepatic CXCR3+ iNKT cells and inhibited RORγt expression. These findings suggest that iNKT17 cells play a key role in EE-induced cholestatic liver injury via CXCR3-mediated recruitment and activation. Our study provides new insights and therapeutic targets for cholestatic diseases.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Colestase , Células T Matadoras Naturais , Camundongos , Animais , Interleucina-17 , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Etinilestradiol/toxicidade , Colestase/induzido quimicamente , Colestase/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Células T Matadoras Naturais/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout
7.
J Cell Mol Med ; 26(2): 475-490, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34890108

RESUMO

At present, growing evidence indicates that long non-coding RNAs (lncRNAs) participate in the progression of glioma. The function of LOXL1-AS1 in vasculogenic mimicry (VM) in glioma remains unclear. First, the expressions of TIAR, the lncRNA LOXL1-AS1, miR-374b-5p and MMP14 were examined by qRT-PCR and Western blot in both, glioma tissues and glioma cell lines. Proliferation, migration, invasion and tube formation assays were conducted to evaluate the roles of TIAR, LOXL1-AS1, miR-374b-5p and MMP14 in malignant cellular behaviours in glioma cells. A nude mouse xenograft model and dual staining for CD34 and PAS were used to assess whether VM was affected by TIAR, LOXL1-AS1 or miR-374b-5p in vivo. In this study, low levels of TIAR and high levels of LOXL1-AS1 were found in glioma cells and tissues. TIAR downregulated the expression of LOXL1-AS1 by destabilizing it. LOXL1-AS1 acted like a miRNA sponge towards miR-374b-5p so that downregulation of the former greatly inhibited cell proliferation, migration, invasion and VM. Additionally, miR-374b-5p overexpression repressed malignant biological behaviours and VM in glioma by modifying MMP14. In summary, we demonstrated that TIAR combined with LOXL1-AS1 modulates VM in glioma via the miR-374b-5p/MMP14 axis, revealing novel targets for glioma therapy.


Assuntos
Glioma , MicroRNAs , RNA Longo não Codificante , Aminoácido Oxirredutases/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/patologia , Humanos , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 14 da Matriz/metabolismo , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/metabolismo
8.
Neuroradiology ; 64(1): 161-169, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34331546

RESUMO

PURPOSE: Perfusion imaging generates multimaps of ischemic tissues and is a proven decision-making tool in patients with acute ischemic stroke. However, the reliability of perfusion post-processing outcomes has been debated, given disparate results of various software applications, especially for patients with small ischemic core volume. This study was undertaken to compare ischemic volume estimates determined by imSTROKE (a software with new imaging protocol) and RAPID computer applications, respectively. METHODS: A total of 611 patients qualified for study, each having met inclusion and exclusion criteria of the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN trial). Subjects were examined by computed tomography perfusion (CTP) imaging (n = 349) or perfusion-weighted (PWI) and diffusion-weighted (DWI) imaging (n = 262). Ischemic volumes estimated by imSTROKE and RAPID applications were then compared. We used Bland-Altman analysis and intraclass correlation coefficients (ICCs) to ascertain agreement between applications. Accuracies of estimated core infarct and penumbra volumes were tested at specific thresholds (core: 25 mL, 50 mL, and 70 mL; penumbra: 45 mL, 90 mL, and 125 mL). RESULTS: Median core infarct volumes by imSTROKE and RAPID were 29.18 mL and 29.53 mL, respectively (ICC = 0.9880, 95% confidence interval [CI]: 0.9860-0.9898). Median penumbra volumes by imSTROKE and RAPID were 68.20 mL and 68.55 mL, respectively (ICC = 0.9885, 95% CI: 0.9865-0.9902). CONCLUSION: In estimating core infarct and penumbra volumes, imSTROKE and RAPID applications showed high-level agreement. For patients with small ischemic core volume, compared with RAPID, imSTROKE may have better sensitivity.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Encéfalo , Isquemia Encefálica/diagnóstico por imagem , Humanos , Perfusão , Imagem de Perfusão , Reprodutibilidade dos Testes , Software , Acidente Vascular Cerebral/diagnóstico por imagem
9.
Biosci Biotechnol Biochem ; 86(12): 1641-1647, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36288245

RESUMO

2,5-furanediformate Isooctyl is a potential new green biobased plasticizer. At present, most of the preparation methods are chemical methods, which not only have many by-products and are difficult to separate, but also cause environmental pollution. In this paper, the immobilized lipase Novozym435 was used as the catalyst to catalyze the transesterification of 2,5-furanediformate dimethyl ester and isooctyl alcohol to prepare 2,5-furanediformate isoocty in organic medium, and the reaction process was optimized. The optimal process conditions were determined by single factor experiment: in 10 mL toluene system, the additional amount of immobilized lipase Novozym435 was 0.02 g, the molar ratio of 2,5-furanediformate dimethyl ester (1 mmol) and isooctyl alcohol was 1:4, and 1 g 4Å molecular sieve was added to the reaction system, the reaction temperature was 50°C, the reaction time was 24 h, and the conversion rate of 2,5-furanediformate isoocty was 89.63%.


Assuntos
Lipase , Plastificantes , Lipase/metabolismo , Ésteres , Esterificação , Biocatálise , Enzimas Imobilizadas/química , Temperatura
10.
J Org Chem ; 86(24): 17816-17832, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34875167

RESUMO

We report a Minisci-type cross-dehydrogenative alkylation in an aerobic atmosphere using abundant and inexpensive cerium chloride as a photocatalyst and air as an oxidant. This photoreaction exhibits excellent tolerance to functional groups and is suitable for both heteroarene and alkane substrates under mild conditions, generating the corresponding products in moderate-to-good yields. Our method provides an alternative approach for the late-stage functionalization of valuable substrates.

11.
RNA Biol ; 18(1): 47-63, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32618493

RESUMO

RNA-binding proteins (RBPs) are significantly dysregulated in glioma. In this study, we demonstrated the upregulation of Nuclear cap-binding subunit 3 (NCBP3) in glioma tissues and cells. Further, knockdown of NCBP3 inhibited the malignant progression of glioma. NCBP3 directly bound to small nucleolar RNA host gene 6 (SNHG6) and stabilized SNHG6 expression. In contrast, the gastrulation brain homeobox 2 (GBX2) transcription factor was downregulated in glioma tissues and cells. SNHG6 inhibited GBX2 transcription by mediating the H3K27me3 modification induced by polycomb repressive complex 2 (PRC2). Moreover, GBX2 decreased the promoter activities and downregulated the expression of the flotillin protein family 1 (FLOT1) oncogene. In conclusion, NCBP3/SNHG6 inhibits GBX2 transcription in a PRC2-dependent manner to facilitate the malignant progression of gliomas.


Assuntos
Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/metabolismo , Histonas/metabolismo , Proteínas de Homeodomínio/genética , Interferência de RNA , RNA Longo não Codificante/genética , Linhagem Celular Tumoral , Progressão da Doença , Técnicas de Silenciamento de Genes , Glioma/patologia , Humanos , Gradação de Tumores , Estadiamento de Neoplasias , Regiões Promotoras Genéticas , Ligação Proteica , Transcrição Gênica , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
12.
Mol Ther ; 28(2): 613-630, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31813799

RESUMO

Studies have found that RNA-binding proteins (RBPs) and long non-coding RNAs (lncRNAs) are dysregulated and play an important regulatory role in the development of tumors. Based on The Cancer Genome Atlas (TCGA) database, our findings from experiments, and the evidence of previous studies, we screened DiGeorge syndrome critical region gene 8 (DGCR8), ZFAT antisense RNA 1 (ZFAT-AS1), and caudal type homeobox 2 (CDX2) as research candidates. In the present study, DGCR8 and CDX2 were highly expressed and ZFAT-AS1 was markedly downregulated in glioma tissues and cells. DGCR8 or CDX2 knockdown or ZFAT-AS1 overexpression suppressed glioma cell proliferation, migration, and invasion and facilitated apoptosis. DGCR8 might decrease ZFAT-AS1 expression by attenuating its stability in a manner of inducing its cleavage. Importantly, ZFAT-AS1 could inhibit CDX2 transcription by mediating the methylation of histone H3 on lysine 27 (H3K27me3) modification induced by PRC2 in the CDX2 promoter region. In addition, CDX2 transcriptionally activated DGCR8 expression by binding to its promoter regions, forming a positive feedback loop of DGCR8/ZFAT-AS1/CDX2. In conclusion, DGCR8/ZFAT-AS1 promotes CDX2 transcription in a PRC2 complex-dependent manner to facilitate the malignant biological behavior of glioma cells.


Assuntos
Fator de Transcrição CDX2/genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , RNA Antissenso , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/genética , Fatores de Transcrição/genética , Animais , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Glioma/metabolismo , Glioma/mortalidade , Glioma/patologia , Humanos , Camundongos , Regiões Promotoras Genéticas , Ligação Proteica , Ensaios Antitumorais Modelo de Xenoenxerto
13.
J Cell Mol Med ; 24(19): 11489-11499, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32914937

RESUMO

The abundance of inflammatory mediators in injured joint indicates innate immune reactions activated during temporomandibular joint osteoarthritis (TMJOA) progression. Toll-like receptor 4 (TLR4) can mediate innate immune reaction. Herein, we aimed to investigate the expression profile and effect of TLR4 in the cartilage and subchondral bone of the discectomy-induced TMJOA mice. The expression of TLR4 and NFκB p65 in the synovium of TMJOA patients was measured by immunohistochemistry, Western blotting and RT-PCR. H&E and Masson staining were utilized to assess the damage of cartilage and subchondral bone of the discectomy-induced TMJOA mice. A TLR4 inhibitor, TAK-242, was used to assess the effect of TLR4 in the cartilage and subchondral bone of the discectomy-induced TMJOA mice by Safranin O, micro-CT, immunofluorescence and immunohistochemistry. Western blotting was used to quantify the expression and effect of TLR4 in IL-1ß-induced chondrocytes. The expression of TLR4 and NFκB p65 was elevated in the synovium of TMJOA patients, compared with the normal synovium. TLR4 elevated in the damaged cartilage and subchondral bone of discectomy-induced TMJOA mice, and the rate of TLR4 expressing chondrocytes positively correlated with OA score. Intraperitoneal injections of TAK-242 ameliorate the extent of TMJOA. Furthermore, TLR4 promotes the expression of MyD88/NFκB, pro-inflammatory and catabolic mediators in cartilage of discectomy-induced TMJOA. Besides, TLR4 participates in the production of MyD88/NFκB, pro-inflammatory and catabolic mediators in IL-1ß-induced chondrocytes. TLR4 contributes to the damage of cartilage and subchondral bone in discectomy-induced TMJOA mice through activation of MyD88/NFκB and release of pro-inflammatory and catabolic mediators.


Assuntos
Osso e Ossos/patologia , Cartilagem Articular/patologia , Discotomia , Osteoartrite/patologia , Articulação Temporomandibular/patologia , Receptor 4 Toll-Like/metabolismo , Adulto , Animais , Condrócitos/metabolismo , Condrócitos/patologia , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-1beta , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Fator 88 de Diferenciação Mieloide/metabolismo , Ratos Sprague-Dawley , Membrana Sinovial/metabolismo , Membrana Sinovial/patologia , Fator de Transcrição RelA/metabolismo , Adulto Jovem
14.
J Cell Mol Med ; 24(11): 6120-6136, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32368853

RESUMO

Increasing evidence has suggested that gliomas can supply blood through vasculogenic mimicry. In this study, the expression and function of ZNRD1-AS1-144aa-uORF (144aa-uORF) and some non-coding RNAs in gliomas were assessed. Real-time quantitative PCR or Western blot was used to discover the expression of 144aa-uORF, ZNRD1-AS1, miR-499a-5p, ELF1 and EMI1 in gliomas. In addition, RIP and RNA pull-down assays were applied to explore the interrelationship between 144aa-uORF and ZNRD1-AS1. The role of the 144aa-uORF\ZNRD1-AS1\miR-499a-5p\ELF1\EMI1 axis in vasculogenic mimicry formation of gliomas was analysed. This study illustrates the reduced expression of the 144aa-uORF in glioma tissues and cells. Up-regulation of 144aa-uORF inhibits proliferation, migration, invasion and vasculogenic mimicry formation within glioma cells. The up-regulated 144aa-uORF can increase the degradation of ZNRD1-AS1 through the nonsense-mediated RNA decay (NMD) pathway. Knockdown of ZNRD1-AS1 inhibits vasculogenic mimicry in glioma cells by modulating miR-499a-5p. At the same time, miR-499a-5p is down-regulated and has a tumour-suppressive effect in gliomas. In addition, ZNRD1-AS1 serves as a competitive endogenous RNA (ceRNA) and regulates the expression of ELF1 by binding to miR-499a-5p. Notably, ELF1 binds to the promoter region of EMI1 and up-regulates EMI1 expression, while simultaneously promoting vasculogenic mimicry in glioma cells. This study suggests that the 144aa-uORF\ZNRD1-AS1\miR-499a-5p\ELF1\EMI1 axis takes key part in regulating the formation of vasculogenic mimicry in gliomas and may provide a potential target for glioma treatment.


Assuntos
Neoplasias Encefálicas/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas F-Box/metabolismo , Glioma/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , MicroRNAs/metabolismo , Proteínas Nucleares/metabolismo , Fases de Leitura Aberta/genética , Transdução de Sinais , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Ligação Competitiva , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , Células HEK293 , Humanos , Camundongos Nus , MicroRNAs/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética , Estabilidade de RNA/genética , Análise de Sobrevida , Regulação para Cima/genética , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Plant Biotechnol J ; 18(2): 457-469, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31314168

RESUMO

Deep roots give rise to flourishing leaves, and the two complement each other. However, the genetic mechanisms underlying adventitious rooting for forest trees have remained elusive. In this study, we verified that peu-miR160a targets six poplar genes AUXIN RESPONSE FACTORS (ARFs), PeARF10.1, PeARF16.1, PeARF16.2, PeARF16.3, PeARF17.1 and PeARF17.2, using 5'RLM-RACE. Interaction experiments with peu-miR160a and PeARFs in poplar protoplasts further confirmed that peu-miR160a targets and negatively regulates the six PeARFs. Peu-miR160a and its target genes exhibited obvious temporal expression in different stages of adventitious root development, and they could also be induced by IAA and abscisic acid. Peu-miR160a-overexpressing lines exhibited a significant shortening of adventitious root length, an increase in the number of lateral roots, severe dwarfing and shortened internodes. In addition, the overexpression of PeARF17.1 or mPeARF17.2 (peu-miR160a-resistant version of PeARF17.2) significantly increased the number of adventitious roots. Furthermore, PeARF17.1-overexpressing lines had multiple branches with no visible trunk, although the adventitious root length of the PeARF17.1-overexpressing lines was significantly increased. Our findings reveal that the peu-miR160a - PeARF17.1/PeARF17.2 module is an important regulator involved in the development of the adventitious roots of poplar.


Assuntos
MicroRNAs , Raízes de Plantas , Populus , Fatores de Transcrição , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Populus/genética , Populus/crescimento & desenvolvimento , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
Toxicol Appl Pharmacol ; 387: 114846, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31790703

RESUMO

Aureusidin, a naturally-occurring flavonoid, is found in various plants of Cyperaceae such as Heleocharis dulcis (Burm. f.) Trin., but its pharmacological effect and active mechanism are rarely reported. This study aimed to investigate the anti-inflammatory effect and action mechanism of Aureusidin in LPS-induced mouse macrophage RAW264.7 cells. The results suggested that lipopolysaccharide (LPS)-induced nitric oxide (NO), tumor necrosis factor-α (TNF-α) and prostaglandin E2 (PGE2) production were obviously inhibited by Aureusidin. Moreover, Aureusidin also significantly decreased the mRNA expression of various inflammatory factors in LPS-stimulated RAW264.7 cells. Furthermore, mechanistic studies showed that Aureusidin significantly inhibited nuclear transfer of nuclear factor-κB (NF-κB), while increasing the nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) as well as expression of Nrf2 target genes such as heme oxygenase (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO1), but the addition of the HO-1 inhibitor Sn-protoporphyrin (Snpp) significantly abolished the anti-inflammatory effect of Aureusidin in LPS-stimulated RAW264.7 cells, confirming the view that HO-1 was involved in the anti-inflammatory effect. In addition, Aureusidin increased the levels of reactive oxygen species (ROS) and mitogen-activated protein kinase (MAPK) phosphorylation in RAW264.7 cells. Antioxidant N-acetylcysteine (NAC) or three MAPK inhibitors blocked the nuclear translocation of Nrf2 and HO-1 expression induced by Aureusidin, indicating that Aureusidin activated the Nrf2/HO-1 signaling pathway through ROS and MAPKs pathways. At the same time, co-treatment with the NAC blocked the phosphorylation of MAPKs. Results from molecular docking indicated that Aureusidin inhibited the NF-κB pathway by covalently binding to NF-κB. Thus, Aureusidin exerted the anti-inflammatory activity through blocking the NF-κB signaling pathways and activating the MAPKs and Nrf2/HO-1 signaling pathways. Based on the above results, Aureusidin may be an attractive therapeutic candidate for the inflammation-related diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Benzofuranos/farmacologia , Inflamação/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Acetilcisteína/farmacologia , Animais , Anti-Inflamatórios/uso terapêutico , Benzofuranos/uso terapêutico , Heme Oxigenase-1 , Humanos , Inflamação/imunologia , Lipopolissacarídeos/imunologia , Sistema de Sinalização das MAP Quinases/imunologia , Proteínas de Membrana , Camundongos , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/imunologia , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo
17.
RNA Biol ; 17(9): 1293-1308, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32372707

RESUMO

The blood-brain barrier (BBB) plays a pivotal role in the maintenance and regulation of the neural microenvironment. The BBB breakdown is a pathological change in early Alzheimer's disease (AD). RNA-binding proteins (RBPs) and long non-coding RNAs (lncRNAs) are involved in the regulation of BBB permeability. Our study demonstrates the role of TRA2A/LINC00662/ELK4 axis in regulating BBB permeability in AD microenvironment. In Aß1-42-incubated microvascular endothelial cells (ECs) of the BBB model in vitro, TRA2A and LINC00662 were enriched. TRA2A increased the stability of LINC00662 by binding with it. The knockdown of either TRA2A or LINC00662 decreased BBB permeability due to increased expression of tight junction-related proteins. ELK4 was less expressed in the BBB model in AD microenvironment in vitro. LINC00662 mediated the degradation of ELK4 mRNA by SMD pathway. Downregulation of ELK4 increased BBB permeability by increasing the tight junction-related protein expression.TRA2A/LINC00662/ELK4 axis plays a crucial role in the regulation of BBB permeability in AD microenvironment, which may provide a novel target for the therapy of AD.


Assuntos
Barreira Hematoencefálica/metabolismo , Microambiente Celular/genética , Regulação da Expressão Gênica , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Elk-4 do Domínio ets/genética , Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Biomarcadores , Células Endoteliais/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Fragmentos de Peptídeos/metabolismo , Permeabilidade , Regiões Promotoras Genéticas , Ligação Proteica , Interferência de RNA , Estabilidade de RNA , RNA Longo não Codificante/genética , Proteínas de Junções Íntimas/genética , Proteínas de Junções Íntimas/metabolismo
18.
Org Biomol Chem ; 17(3): 490-497, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30566159

RESUMO

A highly efficient method to selectively install alkoxy onto the para position of arylamines via a coordinating activation strategy has been reported. Various substrates are compatible, providing the corresponding products in good to excellent yields. This strategy gives an efficient and practical solution for the synthesis of unsymmetrical aryl ethers. A free radical pathway mechanism is advised for transformation.

20.
Mol Cancer ; 16(1): 171, 2017 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-29132362

RESUMO

BACKGROUND: Accumulating evidence has highlighted the potential role of long non-coding RNAs (lncRNAs) in the biological behaviors of glioblastoma stem cells (GSCs). Here, we elucidated the function and possible molecular mechanisms of the effect of lncRNA-SOX2OT on the biological behaviors of GSCs. RESULTS: Real-time PCR demonstrated that SOX2OT expression was up-regulated in glioma tissues and GSCs. Knockdown of SOX2OT inhibited the proliferation, migration and invasion of GSCs, and promoted GSCs apoptosis. MiR-194-5p and miR-122 were down-regulated in human glioma tissues and GSCs, and miR-194-5p and miR-122 respectively exerted tumor-suppressive functions by inhibiting the proliferation, migration and invasion of GSCs, while promoting GSCs apoptosis. Knockdown of SOX2OT significantly increased the expression of miR-194-5p and miR-122 in GSCs. Dual-luciferase reporter assay revealed that SOX2OT bound to both miR-194-5p and miR-122. SOX3 and TDGF-1 were up-regulated in human glioma tissues and GSCs. Knockdown of SOX3 inhibited the proliferation, migration and invasion of GSCs, promoted GSCs apoptosis, and decreased TDGF-1 mRNA and protein expression through direct binding to the TDGF-1 promoter. Over-expression of miR-194-5p and miR-122 decreased the mRNA and protein expression of SOX3 by targeting its 3'UTR. Knockdown of TDGF-1 inhibited the proliferation, migration and invasion of GSCs, promoted GSCs apoptosis, and inhibited the JAK/STAT signaling pathway. Furthermore, SOX3 knockdown also inhibited the SOX2OT expression through direct binding to the SOX2OT promoter and formed a positive feedback loop. CONCLUSION: This study is the first to demonstrate that the SOX2OT-miR-194-5p/miR-122-SOX3-TDGF-1 pathway forms a positive feedback loop and regulates the biological behaviors of GSCs, and these findings might provide a novel strategy for glioma treatment.


Assuntos
Neoplasias Encefálicas/patologia , Proteínas Ligadas por GPI/genética , Glioblastoma/patologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , MicroRNAs/genética , Proteínas de Neoplasias/genética , RNA Longo não Codificante/genética , Fatores de Transcrição SOXB1/genética , Regulação para Cima , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Retroalimentação Fisiológica , Proteínas Ligadas por GPI/metabolismo , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos , Proteínas de Neoplasias/metabolismo , Transplante de Neoplasias , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fatores de Transcrição SOXB1/metabolismo
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