RESUMEN
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.
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Receptores de Glucagón , beta-Arrestina 1 , beta-Arrestina 1/química , beta-Arrestina 1/metabolismo , Membrana Celular/metabolismo , Endocitosis , Endosomas/metabolismo , Glucagón/metabolismo , Proteínas de Unión al GTP Heterotriméricas/metabolismo , Ligandos , Fosfatidilinositoles/metabolismo , Receptores de Glucagón/química , Receptores de Glucagón/metabolismo , Unión ProteicaRESUMEN
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.
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Inteligencia Artificial , Descubrimiento de Drogas , Descubrimiento de Drogas/métodos , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad Cuantitativa , Algoritmos , Diseño de Fármacos , Programas Informáticos , Humanos , Nube ComputacionalRESUMEN
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.
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Farmacorresistencia Bacteriana Múltiple , Pseudomonas aeruginosa , Antibacterianos/farmacología , beta-Lactamasas/genética , Carbapenémicos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Integrones/genética , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/genética , Infecciones por PseudomonasRESUMEN
The escalating frequency, duration, and intensity of extreme heat events have posed a significant threat to human society in recent decades. Understanding the dynamic patterns of human mobility under extreme heat will contribute to accurately assessing the risk of extreme heat exposure. This study leverages an emerging geospatial data source, anonymous cell phone location data, to investigate how people in different communities adapt travel behaviors responding to extreme heat events. Taking the Greater Houston Metropolitan Area as an example, we develop two indices, the Mobility Disruption Index (MDI) and the Activity Time Shift Index (ATSI), to quantify diurnal mobility changes and activity time shift patterns at the city and intra-urban scales. The results reveal that human mobility decreases significantly in the daytime of extreme heat events in Houston while the proportion of activity after 8 p.m. is increased, accompanied with a delay in travel time in the evening. Moreover, these mobility-decreasing and activity-delaying effects exhibited substantial spatial heterogeneity across census block groups. Causality analysis using the Geographical Convergent Cross Mapping (GCCM) model combined with correlation analyses indicates that people in areas with a high proportion of minorities and poverty are less able to adopt heat adaptation strategies to avoid the risk of heat exposure. These findings highlight the fact that besides the physical aspect of environmental justice on heat exposure, the inequity lies in the population's capacity and knowledge to adapt to extreme heat. This research is the first of the kind that quantifies multi-level mobility for extreme heat responses, and sheds light on a new facade to plan and implement heat mitigations and adaptation strategies beyond the traditional approaches.
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Teléfono Celular , Calor Extremo , HumanosRESUMEN
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.
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Infecciones por Pseudomonas , Pseudomonas aeruginosa , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , beta-Lactamasas/metabolismo , Carbapenémicos/uso terapéutico , Células Clonales/metabolismo , Imipenem/farmacología , Imipenem/uso terapéutico , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Infecciones por Pseudomonas/tratamiento farmacológicoRESUMEN
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.
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Ablación por Catéter , Técnicas Electrofisiológicas Cardíacas , Cirugía Asistida por Computador , Humanos , Electrofisiología Cardíaca , Ablación por Catéter/métodos , Técnicas Electrofisiológicas Cardíacas/métodos , Cirugía Asistida por Computador/métodos , Resultado del TratamientoRESUMEN
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.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Colestasis , Células T Asesinas Naturales , Ratones , Animales , Interleucina-17 , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Etinilestradiol/toxicidad , Colestasis/inducido químicamente , Colestasis/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Células T Asesinas Naturales/metabolismo , Ratones Endogámicos C57BL , Ratones NoqueadosRESUMEN
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.
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Glioma , MicroARNs , ARN Largo no Codificante , Aminoácido Oxidorreductasas/metabolismo , Animales , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Glioma/genética , Glioma/patología , Humanos , Metaloproteinasa 14 de la Matriz/genética , Metaloproteinasa 14 de la Matriz/metabolismo , Ratones , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , Proteínas de Unión al ARN/metabolismoRESUMEN
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.
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Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Encéfalo , Isquemia Encefálica/diagnóstico por imagen , Humanos , Perfusión , Imagen de Perfusión , Reproducibilidad de los Resultados , Programas Informáticos , Accidente Cerebrovascular/diagnóstico por imagenRESUMEN
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%.
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Lipasa , Plastificantes , Lipasa/metabolismo , Ésteres , Esterificación , Biocatálisis , Enzimas Inmovilizadas/química , TemperaturaRESUMEN
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.
RESUMEN
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.
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Regulación Neoplásica de la Expresión Génica , Glioma/genética , Glioma/metabolismo , Histonas/metabolismo , Proteínas de Homeodominio/genética , Interferencia de ARN , ARN Largo no Codificante/genética , Línea Celular Tumoral , Progresión de la Enfermedad , Técnicas de Silenciamiento del Gen , Glioma/patología , Humanos , Clasificación del Tumor , Estadificación de Neoplasias , Regiones Promotoras Genéticas , Unión Proteica , Transcripción Genética , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismoRESUMEN
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.
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Factor de Transcripción CDX2/genética , Regulación Neoplásica de la Expresión Génica , Glioma/genética , ARN sin Sentido , ARN Largo no Codificante/genética , Proteínas de Unión al ARN/genética , Factores de Transcripción/genética , Animales , Apoptosis/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Modelos Animales de Enfermedad , Técnicas de Silenciamiento del Gen , Glioma/metabolismo , Glioma/mortalidad , Glioma/patología , Humanos , Ratones , Regiones Promotoras Genéticas , Unión Proteica , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
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.
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Neoplasias Encefálicas/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas F-Box/metabolismo , Glioma/genética , Antígenos de Histocompatibilidad Clase I/metabolismo , MicroARNs/metabolismo , Proteínas Nucleares/metabolismo , Sistemas de Lectura Abierta/genética , Transducción de Señal , Factores de Transcripción/metabolismo , Animales , Secuencia de Bases , Unión Competitiva , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Proliferación Celular/genética , Regulación hacia Abajo/genética , Regulación Neoplásica de la Expresión Génica , Glioma/patología , Células HEK293 , Humanos , Ratones Desnudos , MicroARNs/genética , Regiones Promotoras Genéticas/genética , Unión Proteica/genética , Estabilidad del ARN/genética , Análisis de Supervivencia , Regulación hacia Arriba/genética , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
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.
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Huesos/patología , Cartílago Articular/patología , Discectomía , Osteoartritis/patología , Articulación Temporomandibular/patología , Receptor Toll-Like 4/metabolismo , Adulto , Animales , Condrocitos/metabolismo , Condrocitos/patología , Humanos , Mediadores de Inflamación/metabolismo , Interleucina-1beta , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Factor 88 de Diferenciación Mieloide/metabolismo , Ratas Sprague-Dawley , Membrana Sinovial/metabolismo , Membrana Sinovial/patología , Factor de Transcripción ReIA/metabolismo , Adulto JovenRESUMEN
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.
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MicroARNs , Raíces de Plantas , Populus , Factores de Transcripción , Regulación de la Expresión Génica de las Plantas , Ácidos Indolacéticos/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Populus/genética , Populus/crecimiento & desarrollo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
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.
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Antiinflamatorios/farmacología , Benzofuranos/farmacología , Inflamación/tratamiento farmacológico , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , FN-kappa B/antagonistas & inhibidores , Acetilcisteína/farmacología , Animales , Antiinflamatorios/uso terapéutico , Benzofuranos/uso terapéutico , Hemo-Oxigenasa 1 , Humanos , Inflamación/inmunología , Lipopolisacáridos/inmunología , Sistema de Señalización de MAP Quinasas/inmunología , Proteínas de la Membrana , Ratones , Simulación del Acoplamiento Molecular , Factor 2 Relacionado con NF-E2/metabolismo , FN-kappa B/metabolismo , Fosforilación/efectos de los fármacos , Fosforilación/inmunología , Células RAW 264.7 , Especies Reactivas de Oxígeno/metabolismoRESUMEN
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.
Asunto(s)
Barrera Hematoencefálica/metabolismo , Microambiente Celular/genética , Regulación de la Expresión Génica , ARN Largo no Codificante/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteína Elk-4 del Dominio ets/genética , Enfermedad de Alzheimer/etiología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Biomarcadores , Células Endoteliales/metabolismo , Técnicas de Silenciamiento del Gen , Humanos , Fragmentos de Péptidos/metabolismo , Permeabilidad , Regiones Promotoras Genéticas , Unión Proteica , Interferencia de ARN , Estabilidad del ARN , ARN Largo no Codificante/genética , Proteínas de Uniones Estrechas/genética , Proteínas de Uniones Estrechas/metabolismoRESUMEN
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.