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1.
J Asthma ; : 1-10, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38294683

RESUMO

BACKGROUND: Asthma is a disease characterized by airway hyperresponsiveness and airway inflammation. Icaritin (ICT) is a plant hormone with various pharmacological activities such as anti-inflammatory, immune regulation, and anti-tumor. This study mainly explored the effects of nebulized inhalation of ICT on airway inflammation and airway remodeling in asthmatic mice. METHOD: Different groups of ovalbumin (OVA)-induced asthma mice with acute and chronic airway inflammation received ICT. Asthmatic mice received budesonide (BDND) aerosol inhalation as a positive control, while normal control and asthma model mice received the same volume of saline. Following finishing of the study, analyses were conducted on behavioral tests, biochemical indices, and histological structures of lung tissues. RESULTS: Aerosol inhalation of ICT can notably reduce inflammatory cells infiltration around the airways and pulmonary vessels, and suppressed goblet cell hyperplasia in asthmatic mice. Long-term inhalation of ICT can decrease airway collagen deposition and airway smooth muscle hyperplasia, and alleviate airway hyperresponsiveness, mirroring the effects observed with hormone employed in clinical practice. CONCLUSION: Nebulized inhalation of ICT can effectively inhibit airway inflammation in asthmatic mice, improve airway remodeling, and reduce airway hyperresponsiveness, with effects similar to those of hormones. It may serve as a potential candidate used as a hormone replacement asthma treatment.

2.
Gut ; 72(2): 226-241, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35817555

RESUMO

OBJECTIVE: Gastric cancer (GC) comprises multiple molecular subtypes. Recent studies have highlighted mesenchymal-subtype GC (Mes-GC) as a clinically aggressive subtype with few treatment options. Combining multiple studies, we derived and applied a consensus Mes-GC classifier to define the Mes-GC enhancer landscape revealing disease vulnerabilities. DESIGN: Transcriptomic profiles of ~1000 primary GCs and cell lines were analysed to derive a consensus Mes-GC classifier. Clinical and genomic associations were performed across >1200 patients with GC. Genome-wide epigenomic profiles (H3K27ac, H3K4me1 and assay for transposase-accessible chromatin with sequencing (ATAC-seq)) of 49 primary GCs and GC cell lines were generated to identify Mes-GC-specific enhancer landscapes. Upstream regulators and downstream targets of Mes-GC enhancers were interrogated using chromatin immunoprecipitation followed by sequencing (ChIP-seq), RNA sequencing, CRISPR/Cas9 editing, functional assays and pharmacological inhibition. RESULTS: We identified and validated a 993-gene cancer-cell intrinsic Mes-GC classifier applicable to retrospective cohorts or prospective single samples. Multicohort analysis of Mes-GCs confirmed associations with poor patient survival, therapy resistance and few targetable genomic alterations. Analysis of enhancer profiles revealed a distinctive Mes-GC epigenomic landscape, with TEAD1 as a master regulator of Mes-GC enhancers and Mes-GCs exhibiting preferential sensitivity to TEAD1 pharmacological inhibition. Analysis of Mes-GC super-enhancers also highlighted NUAK1 kinase as a downstream target, with synergistic effects observed between NUAK1 inhibition and cisplatin treatment. CONCLUSION: Our results establish a consensus Mes-GC classifier applicable to multiple transcriptomic scenarios. Mes-GCs exhibit a distinct epigenomic landscape, and TEAD1 inhibition and combinatorial NUAK1 inhibition/cisplatin may represent potential targetable options.


Assuntos
Elementos Facilitadores Genéticos , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Gástricas , Humanos , Cisplatino/metabolismo , Cisplatino/uso terapêutico , Estudos Prospectivos , Proteínas Quinases/genética , Proteínas Repressoras , Estudos Retrospectivos , Neoplasias Gástricas/genética
3.
Gut ; 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38050079

RESUMO

OBJECTIVES: Cholangiocarcinoma (CCA) is a heterogeneous malignancy with high mortality and dismal prognosis, and an urgent clinical need for new therapies. Knowledge of the CCA epigenome is largely limited to aberrant DNA methylation. Dysregulation of enhancer activities has been identified to affect carcinogenesis and leveraged for new therapies but is uninvestigated in CCA. Our aim is to identify potential therapeutic targets in different subtypes of CCA through enhancer profiling. DESIGN: Integrative multiomics enhancer activity profiling of diverse CCA was performed. A panel of diverse CCA cell lines, patient-derived and cell line-derived xenografts were used to study identified enriched pathways and vulnerabilities. NanoString, multiplex immunohistochemistry staining and single-cell spatial transcriptomics were used to explore the immunogenicity of diverse CCA. RESULTS: We identified three distinct groups, associated with different etiologies and unique pathways. Drug inhibitors of identified pathways reduced tumour growth in in vitro and in vivo models. The first group (ESTRO), with mostly fluke-positive CCAs, displayed activation in estrogen signalling and were sensitive to MTOR inhibitors. Another group (OXPHO), with mostly BAP1 and IDH-mutant CCAs, displayed activated oxidative phosphorylation pathways, and were sensitive to oxidative phosphorylation inhibitors. Immune-related pathways were activated in the final group (IMMUN), made up of an immunogenic CCA subtype and CCA with aristolochic acid (AA) mutational signatures. Intratumour differences in AA mutation load were correlated to intratumour variation of different immune cell populations. CONCLUSION: Our study elucidates the mechanisms underlying enhancer dysregulation and deepens understanding of different tumourigenesis processes in distinct CCA subtypes, with potential significant therapeutics and clinical benefits.

4.
Brain Topogr ; 36(4): 581-594, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37115390

RESUMO

Resting-state functional connectivity, constructed via functional magnetic resonance imaging, has become an essential tool for exploring brain functions. Aside from the methods focusing on the static state, investigating dynamic functional connectivity can better uncover the fundamental properties of brain networks. Hilbert-Huang transform (HHT) is a novel time-frequency technique that can adapt to both non-linear and non-stationary signals, which may be an effective tool for investigating dynamic functional connectivity. To perform the present study, we investigated time-frequency dynamic functional connectivity among 11 brain regions of the default mode network by first projecting the coherence into the time and frequency domains, and subsequently by identifying clusters in the time-frequency domain using k-means clustering. Experiments on 14 temporal lobe epilepsy (TLE) patients and 21 age and sex-matched healthy controls were performed. The results show that functional connections in the brain regions of the hippocampal formation, parahippocampal gyrus, and retrosplenial cortex (Rsp) were reduced in the TLE group. However, the connections in the brain regions of the posterior inferior parietal lobule, ventral medial prefrontal cortex, and the core subsystem could hardly be detected in TLE patients. The findings not only demonstrate the feasibility of utilizing HHT in dynamic functional connectivity for epilepsy research, but also indicate that TLE may cause damage to memory functions, disorders of processing self-related tasks, and impairment of constructing a mental scene.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Humanos , Epilepsia do Lobo Temporal/diagnóstico por imagem , Rede de Modo Padrão , Encéfalo/diagnóstico por imagem , Hipocampo , Imageamento por Ressonância Magnética/métodos
5.
Brain Topogr ; 36(4): 554-565, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37204610

RESUMO

Temporal Lobe Epilepsy (TLE) is the most common subtype of focal epilepsy and the most refractory to drug treatment. Roughly 30% of patients do not have easily identifiable structural abnormalities. In other words, MRI-negative TLE has normal MRI scans on visual inspection. Thus, MRI-negative TLE is a diagnostic and therapeutic challenge. In this study, we investigate the cortical morphological brain network to identify MRI-negative TLE. The 210 cortical ROIs based on the Brainnetome atlas were used to define the network nodes. The least absolute shrinkage and selection operator (LASSO) algorithm and Pearson correlation methods were used to calculate the inter-regional morphometric features vector correlation respectively. As a result, two types of networks were constructed. The topological characteristics of networks were calculated by graph theory. Then after, a two-stage feature selection strategy, including a two-sample t-test and support vector machine-based recursive feature elimination (SVM-RFE), was performed in feature selection. Finally, classification with support vector machine (SVM) and leave-one-out cross-validation (LOOCV) was employed for the training and evaluation of the classifiers. The performance of two constructed brain networks was compared in MRI-negative TLE classification. The results indicated that the LASSO algorithm achieved better performance than the Pearson pairwise correlation method. The LASSO algorithm provides a robust method of individual morphological network construction for distinguishing patients with MRI-negative TLE from normal controls.


Assuntos
Epilepsia do Lobo Temporal , Humanos , Epilepsia do Lobo Temporal/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
6.
J Enzyme Inhib Med Chem ; 37(1): 202-210, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34894973

RESUMO

Calcineurin (CN) controls the immune response by regulating nuclear factor of activated T cells (NFAT). Inhibition of CN function is an effective treatment for immune diseases. The PVIVIT peptide is an artificial peptide based on the NFAT-PxIxIT motif, which exhibits stronger binding to CN. A bioactive peptide (named pep4) that inhibits the CN/NFAT interaction was designed. Pep4 contains a segment of A238L as the linker and the LxVP motif and PVIVIT motif as CN binding sites. Pep4 has strong binding capacity to CN and inhibits CN activity competitively. 11-arginine-modified pep4 (11 R-pep4) inhibits the nuclear translocation of NFAT and reduces the expression of IL-2. 11 R-pep4 improves the pathological characteristics of asthmatic mice to a certain extent. The above results indicated that pep4 is a high-affinity CN inhibitor. These findings will contribute to the discovery of new CN inhibitors and promising immunosuppressive drugs.


Assuntos
Asma/tratamento farmacológico , Calcineurina/metabolismo , Fatores de Transcrição NFATC/antagonistas & inibidores , Peptídeos/farmacologia , Animais , Asma/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Fatores de Transcrição NFATC/metabolismo , Peptídeos/síntese química , Peptídeos/química , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade
7.
Int J Mol Sci ; 23(14)2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35887186

RESUMO

The field of immuno-oncology is now at the forefront of cancer care and is rapidly evolving. The immune checkpoint blockade has been demonstrated to restore antitumor responses in several cancer types. However, durable responses can be observed only in a subset of patients, highlighting the importance of investigating the tumor microenvironment (TME) and cellular heterogeneity to define the phenotypes that contribute to resistance as opposed to those that confer susceptibility to immune surveillance and immunotherapy. In this review, we summarize how some of the most widely used conventional technologies and biomarkers may be useful for the purpose of predicting immunotherapy outcomes in patients, and discuss their shortcomings. We also provide an overview of how emerging single-cell spatial omics may be applied to further advance our understanding of the interactions within the TME, and how these technologies help to deliver important new insights into biomarker discovery to improve the prediction of patient response.


Assuntos
Imunoterapia , Neoplasias , Biomarcadores Tumorais , Humanos , Imunidade , Imunoterapia/métodos , Neoplasias/genética , Microambiente Tumoral
8.
J Biol Chem ; 295(9): 2760-2770, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-31941790

RESUMO

The calcineurin/nuclear factor of activated T cell (CN/NFAT) signaling pathway plays a critical role in the immune response. Therefore, inhibition of the CN/NFAT pathway is an important target for inflammatory disease. The conserved PXIXIT and LXVP motifs of CN substrates and targeting proteins have been recognized. Based on the affinity ability and inhibitory effect of these docking sequences on CN, we designed a bioactive peptide (named pep3) against the CN/NFAT interaction, which has two binding sites derived from the RCAN1-PXIXIT motif and the NFATc1-LXVP motif. The shortest linker between the two binding sites in pep3 is derived from A238L, a physiological binding partner of CN. Microscale thermophoresis revealed that pep3 has two docking sites on CN. Pep3 also has the most potent inhibitory effect on CN. It is suggested that pep3 contains an NFATc1-LXVP-substrate recognition motif and RCAN1-PXIXIT-mediated anchoring to CN. Expression of this peptide significantly suppresses CN/NFAT signaling. Cell-permeable 11-arginine-modified pep3 (11R-pep3) blocks the NFAT downstream signaling pathway. Intranasal administration of the 11R-pep3 peptide inhibits airway inflammation in an ovalbumin-induced asthma model. Our results suggest that pep3 is promising as an immunosuppressive agent and can be used in topical remedies.


Assuntos
Calcineurina/metabolismo , Terapia de Imunossupressão/métodos , Fatores de Transcrição NFATC/metabolismo , Peptídeos/farmacologia , Ligação Proteica/efeitos dos fármacos , Motivos de Aminoácidos , Animais , Sítios de Ligação , Humanos , Imunossupressores/farmacologia , Inflamação/tratamento farmacológico , Inflamação/prevenção & controle , Transdução de Sinais/efeitos dos fármacos
9.
Gut ; 69(2): 231-242, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31068366

RESUMO

OBJECTIVE: Gastric cancer (GC) is a leading cause of cancer mortality. Previous studies have shown that hepatocyte nuclear factor-4α (HNF4α) is specifically overexpressed in GC and functionally required for GC development. In this study, we investigated, on a genome-wide scale, target genes of HNF4α and oncogenic pathways driven by HNF4α and HNF4α target genes. DESIGN: We performed HNF4α chromatin immunoprecipitation followed by sequencing across multiple GC cell lines, integrating HNF4α occupancy data with (epi)genomic and transcriptome data of primary GCs to define HNF4α target genes of in vitro and in vivo relevance. To investigate mechanistic roles of HNF4α and HNF4α targets, we performed cancer metabolic measurements, drug treatments and functional assays including murine xenograft experiments. RESULTS: Gene expression analysis across 19 tumour types revealed HNF4α to be specifically upregulated in GCs. Unbiased pathway analysis revealed organic acid metabolism as the top HNF4α-regulated pathway, orthogonally supported by metabolomic analysis. Isocitrate dehydrogenase 1 (IDH1) emerged as a convergent HNF4α direct target gene regulating GC metabolism. We show that wild-type IDH1 is essential for GC cell survival, and that certain GC cells can be targeted by IDH1 inhibitors. CONCLUSIONS: Our results highlight a role for HNF4α in sustaining GC oncogenic metabolism, through the regulation of IDH1. Drugs targeting wild-type IDH1 may thus have clinical utility in GCs exhibiting HNF4α overexpression, expanding the role of IDH1 in cancer beyond IDH1/2 mutated malignancies.


Assuntos
Fator 4 Nuclear de Hepatócito/genética , Isocitrato Desidrogenase/metabolismo , Neoplasias Gástricas/genética , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Marcação de Genes/métodos , Fator 4 Nuclear de Hepatócito/metabolismo , Humanos , Isocitrato Desidrogenase/antagonistas & inibidores , Camundongos Endogâmicos NOD , Terapia de Alvo Molecular/métodos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Regiões Promotoras Genéticas/genética , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Regulação para Cima/genética , Ensaios Antitumorais Modelo de Xenoenxerto
10.
BMC Neurosci ; 21(1): 13, 2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32228575

RESUMO

BACKGROUND: Patients positive for anti-glutamic acid decarboxylase 65 (GAD65) antibodies have attracted increasing attention. Their clinical manifestations are highly heterogeneous and can be comorbid with tumors. Currently, there is no consensus on the therapeutic regimen for anti-GAD65-associated neurological diseases due to the clinical complexity, rarity and sporadic distribution. We reported six anti-GAD65 autoimmune encephalitis (AE) patients who received intravenous methylprednisolone (IVMP) or immunoglobulin (IVIG) or both. Then, we evaluated the therapeutic effect of both by summarizing results in previous anti-GAD65 AE patients from 70 published references. RESULTS: Our six patients all achieved clinical improvements in the short term. Unfortunately, there was no significant difference between IVMP and IVIG in terms of therapeutic response according to the previous references, and the effectiveness of IVMP and IVIG was 45.56% and 36.71%, respectively. We further divided the patients into different subgroups according to their prominent clinical manifestations. The response rates of IVMP and IVIG were 42.65% and 32.69%, respectively, in epilepsy patients; 60.00% and 77.78%, respectively, in patients with stiff-person syndrome; and 28.57% and 55.56%, respectively, in cerebellar ataxia patients. Among 29 anti-GAD65 AE patients with tumors, the response rates of IVMP and IVIG were 29.41% and 42.11%, respectively. There was no significant difference in effectiveness between the two regimens among the different subgroups. CONCLUSION: Except for stiff-person syndrome, we found that this kind of AE generally has a poor response to IVMP or IVIG. Larger prospective studies enrolling large numbers of patients are required to identify the optimal therapeutic strategy in the future.


Assuntos
Encefalite/tratamento farmacológico , Glucocorticoides/administração & dosagem , Glutamato Descarboxilase/imunologia , Doença de Hashimoto/tratamento farmacológico , Imunoglobulinas/administração & dosagem , Fatores Imunológicos/administração & dosagem , Metilprednisolona/administração & dosagem , Administração Intravenosa , Adulto , Autoanticorpos/sangue , Autoanticorpos/líquido cefalorraquidiano , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encefalite/diagnóstico por imagem , Encefalite/imunologia , Feminino , Doença de Hashimoto/diagnóstico por imagem , Doença de Hashimoto/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
11.
Blood ; 132(11): 1146-1158, 2018 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-30054295

RESUMO

Mature T-cell lymphomas, including peripheral T-cell lymphoma (PTCL) and extranodal NK/T-cell lymphoma (NKTL), represent a heterogeneous group of non-Hodgkin lymphomas with dismal outcomes and limited treatment options. To determine the extent of involvement of the JAK/STAT pathway in this malignancy, we performed targeted capture sequencing of 188 genes in this pathway in 171 PTCL and NKTL cases. A total of 272 nonsynonymous somatic mutations in 101 genes were identified in 73% of the samples, including 258 single-nucleotide variants and 14 insertions or deletions. Recurrent mutations were most frequently located in STAT3 and TP53 (15%), followed by JAK3 and JAK1 (6%) and SOCS1 (4%). A high prevalence of STAT3 mutation (21%) was observed specifically in NKTL. Novel STAT3 mutations (p.D427H, E616G, p.E616K, and p.E696K) were shown to increase STAT3 phosphorylation and transcriptional activity of STAT3 in the absence of cytokine, in which p.E616K induced programmed cell death-ligand 1 (PD-L1) expression by robust binding of activated STAT3 to the PD-L1 gene promoter. Consistent with these findings, PD-L1 was overexpressed in NKTL cell lines harboring hotspot STAT3 mutations, and similar findings were observed by the overexpression of p.E616K and p.E616G in the STAT3 wild-type NKTL cell line. Conversely, STAT3 silencing and inhibition decreased PD-L1 expression in STAT3 mutant NKTL cell lines. In NKTL tumors, STAT3 activation correlated significantly with PD-L1 expression. We demonstrated that STAT3 activation confers high PD-L1 expression, which may promote tumor immune evasion. The combination of PD-1/PD-L1 antibodies and STAT3 inhibitors might be a promising therapeutic approach for NKTL, and possibly PTCL.


Assuntos
Antígeno B7-H1/biossíntese , Regulação Neoplásica da Expressão Gênica , Mutação de Sentido Incorreto , Proteínas de Neoplasias/biossíntese , Fator de Transcrição STAT3/biossíntese , Transdução de Sinais , Substituição de Aminoácidos , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/genética , Linhagem Celular Tumoral , Humanos , Linfoma Extranodal de Células T-NK , Proteínas de Neoplasias/genética , Fator de Transcrição STAT3/genética
12.
Acta Neurol Scand ; 142(3): 281-293, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32416610

RESUMO

OBJECTIVES: To examine the clinical characteristics of autoimmune encephalitis associated with the glutamate decarboxylase 65 (GAD 65) antibody. MATERIALS AND METHODS: Medical records of all patients that diagnosed with GAD 65 antibody-associated encephalitis were retrospectively analyzed. Data regarding demographics and symptoms, neurological signs, laboratory and imaging results, treatment and prognosis were collected. RESULTS: We collected a total of seven patients, mainly young or middle-aged women with a subacute or chronic course. The main clinical symptoms mainly included chronic epilepsy, cerebellar ataxia, stiff-person syndrome, and limbic encephalitis. Three of seven (43%) patients had high CSF (cerebrospinal fluid) protein levels. Oligoclonal IgG bands (including IgG 1) and 24 hours intrathecal synthesis of IgG were detected in CSF and serum in six patients, five patients (83%) reported increased distribution of oligoclonal IgG bands (including IgG 1) and 24 hours intrathecal synthesis of IgG in serum and CSF. And six of seven patients (86%) had abnormal thyroid function or were positive for thyroid antibodies. By electroencephalogram examination, sharp or slow waves in the temporal region were often observed for six of seven patients (86%). Abnormal imaging signals (six of seven patients, 86%) of the temporal lobe and hippocampus were detected by brain magnetic resonance imaging, and decreased metabolism of the temporal lobe was detected by positron emission tomography/computed tomography (six of six patients, 100%). These patients were mainly treated with corticosteroid and gamma globulin. The clinical symptoms of the patients were alleviated. CONCLUSIONS: The course of GAD 65 antibody-associated encephalitis is longer than other autoimmune encephalitides. The clinical symptoms of GAD 65 autoimmune encephalitis mainly manifested as chronic epilepsy, cerebellar ataxia, stiff-person syndrome, and limbic encephalitis, and combined with or without thyroid autoimmune diseases, type 1 diabetes, and thymoma. A comprehensive understanding of the disease is a way to prevent misdiagnosis and delayed treatment.


Assuntos
Doenças Autoimunes do Sistema Nervoso/fisiopatologia , Glutamato Descarboxilase/imunologia , Corticosteroides/uso terapêutico , Adulto , Doenças Autoimunes do Sistema Nervoso/complicações , Doenças Autoimunes do Sistema Nervoso/imunologia , Encéfalo/metabolismo , Eletroencefalografia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/líquido cefalorraquidiano , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia , Neuroimagem/métodos , Tomografia por Emissão de Pósitrons , Prognóstico , Estudos Retrospectivos , Substância Negra/diagnóstico por imagem , Doenças da Glândula Tireoide/etiologia , Resultado do Tratamento , gama-Globulinas/uso terapêutico
13.
Plant Cell Rep ; 39(11): 1525-1538, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32860517

RESUMO

KEY MESSAGE: We propose that codA tomato plants exhibited higher degrees of enhanced thermotolerance than BADH tomato plants, and H2O2 as a signaling molecule also plays an important role in heat resistance. Betaine aldehyde dehydrogenase (BADH) and choline oxidase (COD) are key enzymes in glycinebetaine (GB) synthesis. In this study, two kinds of transgenic tomato plants, which were transformed with BADH gene and codA gene, respectively, were used to explore their thermotolerance. Our results showed that the levels of GB in leaves of the fourteen independent transgenic lines ranged from 1.9 µmol g-1 fresh weight to 3.4 µmol g-1 fresh weight, while GB was almost undetectable in leaves of WT plants. CO2 assimilation and photosystem II (PSII) photochemical activity in transgenic plants were more thermotolerant than WT plants, especially the codA-transgenic plants showed the most. Significant accumulation of hydrogen peroxide (H2O2), superoxide anion radical (O2·-), and malondialdehyde (MDA) were more in WT plants than transgenic plants, while this accumulation in codA-transgenic plant was the least. Furthermore, the expression of the heat response genes and the accumulation of heat shock protein 70 (HSP70) were found to be more in transgenic plants than that in WT plants during heat stress, as well as showing the most expression and accumulation of HSP70 in the codA-transgenic plants. Taken together, our results suggest that the enhanced thermotolerance in transgenic plants is due to the positive role of GB in response to heat stress. And interestingly, in addition to the major role of GB in codA-transgenic plants, H2O2 as a signaling molecule may also play an important role in heat resistance, leading to higher thermotolerance compared to BADH-transgenic plants.


Assuntos
Oxirredutases do Álcool/genética , Betaína-Aldeído Desidrogenase/genética , Betaína/metabolismo , Solanum lycopersicum/fisiologia , Antioxidantes/metabolismo , Dióxido de Carbono/metabolismo , Enzimas/genética , Enzimas/metabolismo , Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico/fisiologia , Peróxido de Hidrogênio/metabolismo , Solanum lycopersicum/genética , Malondialdeído/metabolismo , Complexo de Proteína do Fotossistema II/genética , Complexo de Proteína do Fotossistema II/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Plântula/genética , Plântula/crescimento & desenvolvimento , Superóxidos/metabolismo , Termotolerância/genética , Termotolerância/fisiologia
14.
Mol Cell ; 43(5): 798-810, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21884980

RESUMO

Both EZH2 and NF-κB contribute to aggressive breast cancer, yet whether the two oncogenic factors have functional crosstalk in breast cancer is unknown. Here, we uncover an unexpected role of EZH2 in conferring the constitutive activation of NF-κB target gene expression in ER-negative basal-like breast cancer cells. This function of EZH2 is independent of its histone methyltransferase activity but requires the physical interaction with RelA/RelB to promote the expression of NF-κB targets. Intriguingly, EZH2 acts oppositely in ER-positive luminal-like breast cancer cells and represses NF-κB target gene expression by interacting with ER and directing repressive histone methylation on their promoters. Thus, EZH2 functions as a double-facet molecule in breast cancers, either as a transcriptional activator or repressor of NF-κB targets, depending on the cellular context. These findings reveal an additional mechanism by which EZH2 promotes breast cancer progression and underscore the need for developing context-specific strategy for therapeutic targeting of EZH2 in breast cancers.


Assuntos
Neoplasias da Mama/genética , Proteínas de Ligação a DNA/metabolismo , NF-kappa B/genética , Fatores de Transcrição/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Proteína Potenciadora do Homólogo 2 de Zeste , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Reguladores , Humanos , NF-kappa B/metabolismo , Complexo Repressor Polycomb 2 , Fatores de Transcrição/genética
15.
Mikrochim Acta ; 186(8): 594, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31372831

RESUMO

A method is described for the colorimetric determination of the activity of CpG methyltransferase (M.SssI). It is based on (a) the crosslinking effect between dsDNA-modified gold nanoparticles (AuNPs) and graphene oxide (GO), and (b) an amplification reaction with the aid of a nicking enzyme. To avoid the aggregation of AuNPs (which would produce false signals), a hairpin DNA was connected to the AuNPs. Thus, the red color of the solution (measured at 530 nm) increases linearly with the activity of M.SssI from 0.2 to 60 U·mL-1, and the limit of detection is 67 U·mL-1. This is superior to some reported strategies. The method was successfully applied to analyze spiked serum samples. Conceivably, it represents a powerful tool for use in drug development and diagnosis. Graphical abstracts A method based on the conjugated cross-linking effect between dsDNA modified Au NPs and GO coupled with an amplification reaction of nicking enzyme has been developed for colorimetric detection of the activity of CpG methyltransferase (M.SssI).

16.
Mikrochim Acta ; 186(11): 732, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667627

RESUMO

The authors describe an electrochemical and an optical method for the determination of As(V) by using iron oxyhydroxide (FeOOH) nanorods that display peroxidase-mimicking activity. The nanorods catalyze the oxidation of substrate ABTS by H2O2 to form a green product with an absorption maximum at 418 nm. If, however, As(V) is electrostatically adsorbed on the nanorods, the oxidation is gradually inhibited. A colorimetric assay was worked out based on these findings. Response is linear in the 0 to 8 ppb and 8 to 200 ppb As(V) concentration range, and the detection limit is 0.1 ppb. Even higher sensitivity is achieved in an electrochemical method which is based on the excellent electrical conductivity of FeOOH nanorods. Electrochemical analysis of As(V) was achieved by first adsorbing As(V) on the nanorods. This inhibits the ABTS reduction current signal, best measured at a potential of 150 mV (vs. Ag/AgCl). The linear range extends from 0.04 to 200 ppb, and the detection limit is as low as 12 ppt. Graphical abstract Schematic representation of FeOOH nanorod-based colorimetric and electrochemical assays for arsenate (As(V)). As(V) adsorbed on FeOOH nanorods inhibits the peroxidase-mimicking activity of nanorods, and a colorimetric and electrochemical dual-signal assay was constructed to achieve sensitive determination of As(V).


Assuntos
Arseniatos/análise , Colorimetria/métodos , Técnicas Eletroquímicas/métodos , Compostos Férricos/química , Nanotubos/química , Poluentes Químicos da Água/análise , Benzotiazóis/química , Materiais Biomiméticos/química , Catálise , Água Potável/análise , Peróxido de Hidrogênio/química , Lagos/análise , Limite de Detecção , Peroxidase/química , Rios/química , Ácidos Sulfônicos/química
17.
Mikrochim Acta ; 186(4): 241, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30868262

RESUMO

The activity of terminal deoxynucleotidyl transferase (TdTase) is a biomarker for routine diagnosis of acute leukemia. A method has been developed for the determination of TdTase activity. It is based on the use of silver nanoclusters (AgNCs) whose yellow fluorescence is enhanced by an in-situ grown DNA tail of TdTase-polymerized and guanine-rich DNA at the 3' end of a hairpin DNA. The fluorescence, best measured at excitation/emission peaks of 530/585 nm, increases linearly in the 1 to 35 mU mL-1 TdTase activity range. The detection limit is 0.8 mU mL-1. The method is cost-efficient, selective and convenient. It integrates enhancement of the fluorescence of AgNCs and target recognition into a single process. Graphical abstract Schematic presentation of a method for determination of TdTase activity. It is based on AgNCs fluorescence enhanced by in-situ grown TdTase-polymerized G-rich DNA tail. The method integrates AgNCs fluorescence enhancement and the target recognition into a single process.


Assuntos
DNA Nucleotidilexotransferase/sangue , DNA/química , Ensaios Enzimáticos/métodos , Nanopartículas Metálicas/química , Sequência de Bases , Biomarcadores/sangue , Técnicas Biossensoriais/métodos , DNA/genética , Fluorescência , Humanos , Sequências Repetidas Invertidas , Leucemia/diagnóstico , Limite de Detecção , Prata/química , Espectrometria de Fluorescência/métodos
18.
Biochem Biophys Res Commun ; 496(4): 1109-1114, 2018 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-29409956

RESUMO

Calcineurin (CN) is a protein phosphatase and widely distributed in eukaryotes, with an extremely high level of expression in mammalian brain. Alpha-synuclein (α-syn) is a small soluble protein expressed primarily at presynaptic terminals in the central nervous system. In our present study, we explored the interactions between CN and α-syn in vitro. Based on the data from microscale thermophoresis, GST pull-down assays, and co-immunoprecipitation, we found that CN binds α-syn. Furthermore, this interaction is mediated by calcium/calmodulin (Ca2+/CaM) signaling. Additionally, thapsigargin (TG) triggered an increase in CN activity and α-syn aggregation in HEK293 cells stably transfected with α-syn. Our previous study in vivo suggest that overexpression of α-syn in transgenic mice significantly promoted CN activity and subsequent nuclear translocation of nuclear factor of activated T-cells (NFAT) in the midbrain dopaminergic (mDA) neurons. These in vivo and in vitro studies have been complementary with each other, representing the changes in the CN-dependent pathway affected by overexpression of α-syn.


Assuntos
Calcineurina/metabolismo , Cálcio/metabolismo , Calmodulina/metabolismo , Regulação da Expressão Gênica/fisiologia , Transdução de Sinais/fisiologia , alfa-Sinucleína/metabolismo , Células HEK293 , Humanos , Ligação Proteica , Mapeamento de Interação de Proteínas
19.
Cell Tissue Res ; 374(3): 653-666, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30073544

RESUMO

Testicular dysfunction is one of the serious secondary complications in diabetes. Lycium barbarum polysaccharide (LBP) has long been considered to possess a wide range of beneficial properties including antiaging, anticancer and reproductive-enhancing. Abnormal autophagy was reported to play a significant role in accelerating diabetic reproductive injury. However, the autophagy regulation mechanism of LBP on diabetic testicular dysfunction is incompletely understood. We investigate the protective effects of LBP on diabetic testicular dysfunction and its underlying mechanism with different approaches. Protective effects of LBP (40 mg/kg) on testicular functions were assessed through the use of sperm parameters, testosterone levels and hematoxylin and eosin staining. Antioxidant capacity and serum malondialdehyde levels were determined using assay kits. Immune intensity of Beclin-1 and LC3I in testes was detected by immunofluorescence staining. Western blot analysis was used to detect expressions of p-PI3K, Akt, p-Akt, Beclin-1, LC3I and LC3II proteins. Q-PCR was used to evaluate Beclin-1 and LC3I mRNA expressions in testis. Administration of LBP (40 mg/kg) considerably recovered testicular function, obviously improved testicular histopathologic structure and significantly increased antioxidant enzyme activities. Immunofluorescence staining showed that immune intensity of Beclin-1 and LC3I significantly decreased in the LBP 40 mg/kg group. The results of Q-PCR and western blot analysis showed that LBP 40 mg/kg significantly downregulated Beclin-1 and LC3I protein expressions upregulated p-PI3K and p-Akt protein expressions and decreased Beclin-1 and LC3I mRNA expressions compared with diabetic mice. In conclusion, inhibition of PI3K/Akt pathway-mediated testicular excessive autophagy may be a target for protective effects of LBP on diabetic testicular dysfunction.


Assuntos
Autofagia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/fisiopatologia , Medicamentos de Ervas Chinesas/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Testículo/patologia , Testículo/fisiopatologia , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Autofagossomos/ultraestrutura , Autofagia/efeitos dos fármacos , Autofagia/genética , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Proteína Beclina-1/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/genética , Medicamentos de Ervas Chinesas/farmacologia , Masculino , Camundongos Endogâmicos ICR , Proteínas Associadas aos Microtúbulos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos , Testosterona/sangue
20.
Bioorg Chem ; 77: 478-484, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29454280

RESUMO

8-Chrysoeriol, a bioactive flavanoid, was firstly identified to bind directly to BCL-2 as BH3 mimetics by structure-based virtual ligand screening. And 3D docking model revealed the molecular basis of 8-Chrysoeriol targeting to BCL-2. The interaction between 8-Chrysoeriol and BCL-2 was further confirmed using Microscale Thermophoresis (MST) technique. Meanwhile, high expression level of antiapoptotic protein BCL-2 was detected in SW1990 pancreatic cancer cells and 8-Chrysoeriol showed obvious proapoptosis effect against SW1990 in vitro. Collectively, the results showed that 8-Chrysoeriol as a natural dietary product potentially targeting to BCL-2 could serve as a lead compound for SW1990 pancreatic cancer therapy.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Flavonas/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Flavonas/química , Flavonas/isolamento & purificação , Humanos , Ligantes , Simulação de Acoplamento Molecular , Estrutura Molecular , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
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