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1.
Thorac Cancer ; 14(36): 3503-3510, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37920959

RESUMO

BACKGROUND: Persistent cough is one of the most frequent complications following lung cancer surgery. To promote optimal recovery, we conducted a study to investigate the trajectories of coughing symptoms and their impact on quality of life (QOL), as well as to identify potential risk factors of persistent cough after pulmonary resection (CAP). METHODS: This prospective observational study assessed patients who underwent pulmonary resection for lung tumor at two medical centers in China. Persistent CAP was evaluated before surgery, at discharge, and 1, 3, and 6 months following surgery using visual analog scale (VAS), cough symptom score (CSS), and Leicester Cough Questionnaire in Mandarin Chinese (LCQ-MC). Univariate and multivariate logistic regression analyses were conducted to explore independent risk factors for persistent CAP. RESULTS: Of the 506 enrolled patients, 130 patients were diagnosed with persistent CAP with an incidence of 25.69%. Compared to the noncough group, patients with persistent CAP reported significantly higher VAS (p < 0.001) and CSS scores (p < 0.001) and experienced worse QOL (p < 0.001) for up to 6 months, particularly at 1 month following surgery. Multivariable regression analysis revealed that a duration of anesthesia exceeding 156 min (odds ratio [OR]: 1.847, 95% confidence interval [CI]: 1.156-2.951, p = 0.010) and gastroesophageal acid reflux (GER) (OR: 3.870, 95% CI: 2.376-6.304, p < 0.001) were independent risk factors of persistent CAP. CONCLUSION: Patients who suffer from persistent CAP face a substantial burden and diminished QOL for an extended period compared to noncough patients. Moreover, prolonged duration of anesthesia and postoperative GER are potential risk factors of persistent CAP.


Assuntos
Tosse Crônica , Qualidade de Vida , Humanos , Estudos Prospectivos , Tosse/etiologia , Tosse/epidemiologia , Fatores de Risco
2.
Artigo em Inglês | MEDLINE | ID: mdl-37999452

RESUMO

OBJECTIVE: This article examined the cost-effectiveness of zanubrutinib and ibrutinib for managing relapsed and refractory chronic lymphocytic leukemia from the viewpoint of payers in China and the US. METHODS: Markov models were employed to conduct comparisons. Baseline characteristics and clinical data were extracted from the ALPINE study. The cost-effectiveness outcome indicators encompassed cost, quality-adjusted life years, and the incremental cost-effectiveness ratio. RESULTS: The Markov model analysis revealed that the zanubrutinib group incurred an incremental cost per patient of $-24,586.53 compared to the ibrutinib group. The zanubrutinib group exhibited an incremental utility per capita of 0.28 quality-adjusted life years, resulting in an incremental cost-effectiveness ratio of $-88,068.16 per quality-adjusted life year, which is lower than the payment threshold in China. The willingness-to-pay value in China for 2022 was three times the country's gross domestic product per capita. In the US, patients in the zanubrutinib group experienced per capita incremental costs of $-79,421.56, per capita incremental utility of 0.28 quality-adjusted life years, and an incremental cost-effectiveness ratio of $-284,485.45 per quality-adjusted life year. CONCLUSION: For Chinese payers, zanubrutinib exhibited superior cost-effectiveness compared to ibrutinib. Zanubrutinib proved to be a more affordable option for US payers when considering the payment threshold.

3.
Front Immunol ; 14: 1232858, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38022553

RESUMO

Background: The efficacy of current adjuvant chemotherapy for gastric adenocarcinoma/gastroesophageal junction adenocarcinoma (GA/GEJA) leaves much to be desired. ctDNA could serve as a potential marker to identify patients who are at higher risk of recurrence. Reinforcing standard adjuvant chemotherapy with immunotherapy has already been indicated to significantly improve clinical outcome, albeit such evidence is rare in GA/GEJA. Here, we intend to explore the clinical benefit of the reinforcement of adjuvant immunotherapy and antiangiogenics alongside with chemotherapy in patients who are deemed in high risk of recurrence by ctDNA analysis, which might shed light on further improvements in adjuvant therapy for GA/GEJA. Methods/Design: This study is designed as a prospective, multicenter, randomized, controlled phase II study in patients histologically or cytologically diagnosed with GA/GEJA who underwent D2 gastrectomy and achieved R0 or R1 resection. From February 2022, a total of 300 stage III patients will be enrolled and subjected according to ctDNA sequencing results, and those with positive results will subsequently be randomized 1:1 to arm A or B. Patients in arm A will receive anlotinib, penpulimab and XELOX for 6-8 cycles, maintained with anlotinib and penpulimab for up to 1 year, while patients in arm B will receive XELOX alone for 6-8 cycles. ctDNA-negative patients will be assigned to arm C, and patients who are ctDNA positive but failed in randomization will be assigned to arm D. Patients in arms C and D will receive the investigator's choice of therapy. The primary endpoint is the median disease-free survival (DFS) of arm A versus arm B determined via CT/MRI imaging. Secondary endpoints include the DFS of ctDNA positive patients versus ctDNA negative patients, the 2- and 3-year DFS rates, overall survival (OS), the impact of hallmark molecules on the treatment response, adverse events (AEs), and the impact of nutrition status or exercise on recurrence. Discussion: We expect that ctDNA would be a strong prognostic factor and ctDNA-positive patients are at higher risk of relapse than ctDNA-negative patients. The addition of anlotinib and penpulimab to XELOX, may contribute to delaying relapse in ctDNA-positive patients. Trial registration: https://www.clinicaltrials.gov, identifier NCT05494060.


Assuntos
Adenocarcinoma , Fluoruracila , Humanos , Fluoruracila/uso terapêutico , Estudos Prospectivos , Oxaliplatina/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Junção Esofagogástrica , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Recidiva , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto , Ensaios Clínicos Fase II como Assunto
4.
JHEP Rep ; 5(7): 100763, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37333974

RESUMO

Background & Aims: Immunotherapy is an option for the treatment of advanced biliary tract cancer (BTC), although it has a low response rate. In this post hoc analysis, we investigated the predictive value of an immuno-genomic-radiomics (IGR) analysis for patients with BTC treated with camrelizumab plus gemcitabine and oxaliplatin (GEMOX) therapy. Methods: Thirty-two patients with BTC treated with camrelizumab plus GEMOX were prospectively enrolled. The relationship between high-throughput computed tomography (CT) radiomics features with immuno-genomic expression was tested and scaled with a full correlation matrix analysis. Odds ratio (OR) of IGR expression for objective response to camrelizumab plus GEMOX was tested with logistic regression analysis. Association of IGR expression with progression-free survival (PFS) and overall survival (OS) was analysed with a Cox proportional hazard regression. Results: CT radiomics correlated with CD8+ T cells (r = -0.72-0.71, p = 0.004-0.047), tumour mutation burden (TMB) (r = 0.59, p = 0.039), and ARID1A mutation (r = -0.58-0.57, p = 0.020-0.034). There was no significant correlation between radiomics and programmed cell death protein ligand 1 expression (p >0.96). Among all IGR biomarkers, only four radiomics features were independent predictors of objective response (OR = 0.09-3.81; p = 0.011-0.044). Combining independent radiomics features into an objective response prediction model achieved an area under the curve of 0.869. In a Cox analysis, radiomics signature [hazard ratio (HR) = 6.90, p <0.001], ARID1A (HR = 3.31, p = 0.013), and blood TMB (HR = 1.13, p = 0.023) were independent predictors of PFS. Radiomics signature (HR = 6.58, p <0.001) and CD8+ T cells (HR = 0.22, p = 0.004) were independent predictors of OS. Prognostic models integrating these features achieved concordance indexes of 0.677 and 0.681 for PFS and OS, respectively. Conclusions: Radiomics could act as a non-invasive immuno-genomic surrogate of BTC, which could further aid in response prediction for patients with BTC treated with immunotherapy. However, multicenter and larger sample studies are required to validate these results. Impact and implications: Immunotherapy is an alternative for the treatment of advanced BTC, whereas tumour response is heterogeneous. In a post hoc analysis of the single-arm phase II clinical trial (NCT03486678), we found that CT radiomics features were associated with the tumour microenvironment and that IGR expression was a promising marker for tumour response and long-term survival. Clinical trial number: Post hoc analysis of NCT03486678.

5.
Biomed Pharmacother ; 153: 113530, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36076610

RESUMO

To verify the role of myricetin in alleviating the symptoms of type 2 diabetes and regulating the intestinal flora, we established a type 2 diabetes mouse model. After being fed a high-fat and high-sugar diet for six weeks, mice were intraperitoneally injected with streptozotocin (80 mg/kg body weight [BW]) 2-3 times. Type 2 diabetes mice were randomly divided into type 2 diabetes control (T2DM) and myricetin intervention groups. Water and food intake, fasting blood glucose (FBG), and BW were monitored weekly. After six weeks of myricetin administration, superoxide dismutase (SOD) levels and blood lipid content were measured. Furthermore, 16S rRNA sequencing was used to detect the gut microbiota composition. FBG and blood lipid levels of T2DM mice were significantly reduced upon myricetin treatment, while SOD levels were increased. Myricetin improved polydipsia, polyphagia, polyuria, and weight loss in T2DM mice. In addition, the signature type 2 diabetes microflora was established by analyzing the microflora structure of healthy mice, type 2 diabetes mice, and mice treated with myricetin. Results showed that type 2 diabetes disrupted the mice intestinal flora, and myricetin intervention normalized the intestinal flora. In conclusion, our results indicate that myricetin alleviates type 2 diabetes in mice and regulates the intestinal microflora.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dieta Hiperlipídica , Flavonoides , Microbioma Gastrointestinal/fisiologia , Lipídeos , Camundongos , RNA Ribossômico 16S , Superóxido Dismutase
6.
Front Oncol ; 12: 923641, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35719911

RESUMO

Backgrounds: Uterine corpus endometrial carcinoma (UCEC) is one of the greatest threats on the female reproductive system. The aim of this study is to explore the inflammation-related LncRNA (IRLs) signature predicting the clinical outcomes and response of UCEC patients to immunotherapy and chemotherapy. Methods: Consensus clustering analysis was employed to determine inflammation-related subtype. Cox regression methods were used to unearth potential prognostic IRLs and set up a risk model. The prognostic value of the prognostic model was calculated by the Kaplan-Meier method, receiver operating characteristic (ROC) curves, and univariate and multivariate analyses. Differential abundance of immune cell infiltration, expression levels of immunomodulators, the status of tumor mutation burden (TMB), the response to immune checkpoint inhibitors (ICIs), drug sensitivity, and functional enrichment in different risk groups were also explored. Finally, we used quantitative real-time PCR (qRT-PCR) to confirm the expression patterns of model IRLs in clinical specimens. Results: All UCEC cases were divided into two clusters (C1 = 454) and (C2 = 57) which had significant differences in prognosis and immune status. Five hub IRLs were selected to develop an IRL prognostic signature (IRLPS) which had value in forecasting the clinical outcome of UCEC patients. Biological processes related to tumor and immune response were screened. Function enrichment algorithm showed tumor signaling pathways (ERBB signaling, TGF-ß signaling, and Wnt signaling) were remarkably activated in high-risk group scores. In addition, the high-risk group had a higher infiltration level of M2 macrophages and lower TMB value, suggesting patients with high risk were prone to a immunosuppressive status. Furthermore, we determined several potential molecular drugs for UCEC. Conclusion: We successfully identified a novel molecular subtype and inflammation-related prognostic model for UCEC. Our constructed risk signature can be employed to assess the survival of UCEC patients and offer a valuable reference for clinical treatment regimens.

7.
Mol Ther ; 30(10): 3133-3154, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-35405312

RESUMO

Exosomes have a crucial role in intercellular communication and mediate interactions between tumor cells and tumor-associated macrophages (TAMs). Exosome-encapsulated non-coding RNAs (ncRNAs) are involved in various physiological processes. Tumor-derived exosomal ncRNAs induce M2 macrophage polarization through signaling pathway activation, signal transduction, and transcriptional and post-transcriptional regulation. Conversely, TAM-derived exosomal ncRNAs promote tumor proliferation, metastasis, angiogenesis, chemoresistance, and immunosuppression. MicroRNAs induce gene silencing by directly targeting mRNAs, whereas lncRNAs and circRNAs act as miRNA sponges to indirectly regulate protein expressions. The role of ncRNAs in tumor-host interactions is ubiquitous. Current research is increasingly focused on the tumor microenvironment. On the basis of the "cancer-immunity cycle" hypothesis, we discuss the effects of exosomal ncRNAs on immune cells to induce T cell exhaustion, overexpression of programmed cell death ligands, and create a tumor immunosuppressive microenvironment. Furthermore, we discuss potential applications and prospects of exosomal ncRNAs as clinical biomarkers and drug delivery systems.


Assuntos
Exossomos , MicroRNAs , Neoplasias , RNA Longo não Codificante , Exossomos/genética , Exossomos/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias/patologia , RNA Circular , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , Microambiente Tumoral/genética , Macrófagos Associados a Tumor
8.
Nucleic Acids Res ; 47(13): 6769-6782, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31053851

RESUMO

We reconstituted two biochemical processes that may contribute to UV-induced mutagenesis in vitro and analysed the mutational profiles in the products. One process is translesion synthesis (TLS) by DNA polymerases (Pol) δ, η and ζ, which creates C>T transitions at pyrimidine dimers by incorporating two dAMPs opposite of the dimers. The other process involves spontaneous deamination of cytosine, producing uracil in pyrimidine dimers, followed by monomerization of the dimers by secondary UV irradiation, and DNA synthesis by Pol δ. The mutational spectrum resulting from deamination without translesion synthesis is similar to a mutational signature found in melanomas, suggesting that cytosine deamination encountered by the replicative polymerase has a prominent role in melanoma development. However, CC>TT dinucleotide substitution, which is also commonly observed in melanomas, was produced almost exclusively by TLS. We propose that both TLS-dependent and deamination-dependent mutational processes are likely involved in UV-induced melanoma development.


Assuntos
Dano ao DNA , DNA de Cadeia Simples/efeitos da radiação , Melanoma/genética , Modelos Genéticos , Mutagênese/efeitos da radiação , Neoplasias Induzidas por Radiação/genética , Dímeros de Pirimidina , Neoplasias Cutâneas/genética , Raios Ultravioleta/efeitos adversos , 5-Metilcitosina/efeitos da radiação , Sistema Livre de Células , Citosina/química , Citosina/efeitos da radiação , Replicação do DNA , DNA de Neoplasias/química , DNA de Neoplasias/genética , DNA de Cadeia Simples/química , DNA-Citosina Metilases/metabolismo , DNA Polimerase Dirigida por DNA/metabolismo , Desaminação , Humanos , Melanoma/etiologia , Dímeros de Pirimidina/química , Neoplasias Cutâneas/etiologia , Transcriptoma
9.
Brain Res Bull ; 69(2): 109-16, 2006 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-16533658

RESUMO

In the present study, we investigated whether activation of mitochondrial ATP-sensitive potassium channel is involved in the neuroprotective effect offered by early hyperbaric oxygenation after cerebral ischemia. The selective mitochondrial ATP-sensitive potassium channel antagonist 5-hydroxydecanoate was infused intracerebroventricularly before hyperbaric oxygenation treatment initiated 3 h after middle cerebral artery occlusion for 90 min. Neurological status was evaluated and brains were removed for the measurement of infarct size and immunohistochemical evaluation of apoptosis 24 h after middle cerebral artery occlusion. Early hyperbaric oxygenation treatment improved neurologic deficits and reduced infarct volume, while these effects were reversed by the administration of 5-hydroxydecanoate. Furthermore, early hyperbaric oxygenation significantly decreased the number of apoptotic cells in the peri-infarct cortex 24 h after ischemic insult and this effect was also blocked by 5-hydroxydecanoate. The present findings suggest that early hyperbaric oxygenation therapy prevents apoptosis and promotes neurologic functional recovery after focal cerebral ischemia, and the opening of mitochondrial ATP-sensitive potassium channel plays a role in this antiapoptotic effect of early hyperbaric oxygenation.


Assuntos
Isquemia Encefálica/metabolismo , Encéfalo/metabolismo , Citoproteção/fisiologia , Oxigenoterapia Hiperbárica , Mitocôndrias/metabolismo , Canais de Potássio/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/fisiologia , Encéfalo/fisiopatologia , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/terapia , Infarto Cerebral/fisiopatologia , Infarto Cerebral/prevenção & controle , Infarto Cerebral/terapia , Modelos Animais de Doenças , Metabolismo Energético/fisiologia , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/fisiopatologia , Infarto da Artéria Cerebral Média/terapia , Masculino , Degeneração Neural/fisiopatologia , Degeneração Neural/prevenção & controle , Degeneração Neural/terapia , Oxigênio/metabolismo , Consumo de Oxigênio/fisiologia , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
10.
Endocrinology ; 146(9): 4036-41, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15961565

RESUMO

Glucocorticoid (GC) acts through both genomic and nongenomic mechanisms. It affects the structure and function of the central nervous system, especially the hippocampus. Here we report an in vitro culture system that can yield embryonic hippocampal neurons deficient in the expression of GC receptor as demonstrated by immunoblotting, immunocytochemistry, and RT-PCR. Owing to this unique feature, those neuron preparations can serve as an ideal model for studying the nongenomic actions of GC on neural cells. In this study, we found that the Erk1/2, c-Jun N-terminal kinase (JNK), and p38 MAPKs were activated in these neurons by BSA-conjugated corticosterone within 15 min of treatment. This activation was not blocked by RU38486, spironolactone, or cycloheximide. Therefore, it is concluded that the activation of MAPKs observed here was due to the nongenomic action of GC. Furthermore, a 24-h incubation with corticosterone at concentrations ranged from 10(-11)-10(-5) M did not have an effect on the viability of GC receptor-deficient neurons.


Assuntos
Técnicas de Cultura de Células/métodos , Hipocampo/citologia , Sistema de Sinalização das MAP Quinases/fisiologia , Neurônios/metabolismo , Receptores de Glucocorticoides/genética , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Corticosterona/farmacologia , Meios de Cultura Livres de Soro/farmacologia , Cicloeximida/farmacologia , Hipocampo/embriologia , Antagonistas de Hormônios/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Mifepristona/farmacologia , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neurônios/citologia , Células PC12 , Fosforilação/efeitos dos fármacos , Inibidores da Síntese de Proteínas/farmacologia , RNA Mensageiro/análise , Ratos , Receptores de Glucocorticoides/metabolismo , Soroalbumina Bovina/farmacologia , Espironolactona/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
Acta Pharmacol Sin ; 26(2): 199-204, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15663899

RESUMO

AIM: In our previous observations, adenosine triphosphate (ATP) was found to evoke immediate elevations in intracellular free calcium concentration ([Ca2+]i) in HT4 neuroblastoma cells of mice. We tried to see if a brief pretreatment of glucocorticoids could inhibit the Ca2+ response and reveal the underlying signaling mechanism. METHODS: Measurement of [Ca2+]i was carried out using the dual-wavelength fluorescence method with Fura-2 as the indicator. RESULTS: Pre-incubation of HT4 cells for 5 min with corticosterone (B) or bovine serum albumin conjugated corticosterone (B-BSA) inhibited the peak [Ca2+]i increments in a concentration-dependent manner. Cortisol and dexamethasone had a similar action, while deoxycorticosterone and cholesterol were ineffective. Both extracellular Ca2+ influx and internal Ca2+ release contributed to ATP-induced [Ca2+]i elevation. The brief treatment with only B attenuated Ca2+ influx. Furthermore, the [Ca2+]i elevation induced by the P2X receptor agonist adenosine 5'-(beta, gamma-methylene) triphosphate (beta, gamma-meATP) was also suppressed. The rapid inhibitory effect of B can be reproduced by forskolin 1 mmol/L and blocked by H89 20 mmol/L. Neither nuclear glucocorticoid receptor antagonist mifepristone nor protein kinase C inhibitors influenced the rapid action of B. CONCLUSION: Our results suggest that glucocorticoids modulate P2X receptor-medicated Ca2+ influx through a membrane-initiated, non-genomic and PKA-dependent pathway in HT4 cells.


Assuntos
Trifosfato de Adenosina/antagonistas & inibidores , Cálcio/metabolismo , Corticosterona/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Transdução de Sinais , Trifosfato de Adenosina/análogos & derivados , Animais , Linhagem Celular Tumoral , Dexametasona/farmacologia , Relação Dose-Resposta a Droga , Hidrocortisona/farmacologia , Isoquinolinas/farmacologia , Camundongos , Neuroblastoma/patologia , Agonistas do Receptor Purinérgico P2 , Receptores Purinérgicos P2X , Albumina Sérica/farmacologia , Sulfonamidas/farmacologia
12.
J Neuroimmunol ; 156(1-2): 107-12, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15465601

RESUMO

We have reported that there are distinct domains in Interferon-alpha (IFNalpha) molecule mediating immune and opioid-like effects respectively. And the opioid effect of IFNalpha is mediated by mu opioid receptor. We report here the structural basis of fever induced by recombinant human IFNalpha. Two kinds of IFNalpha mutants were obtained and used to investigate the structural basis of fever of IFNalpha, which are 129Ser-IFNalpha and 38Leu-IFNalpha. The antiviral activity of 129Ser-IFNalpha almost disappeared, but there still retained the strong analgesic activity. The antiviral activity of 38Leu-IFNalpha remained, but the analgesic activity disappeared completely. It showed that IFNalpha and 129Ser-IFNalpha decreased cAMP production, induced the fever, and stimulated PGE2 to release from the hypothalamus slices, which could be blocked by naloxone, but 38Leu-IFNalpha failed. It is the first demonstration that fever induced by IFNalpha is mediated by opioid domain of IFNalpha interacting with opioid receptor. It is inferred that high-activity and low side-effect IFNalpha or other cytokines could be obtained after being changed the motifs in the tertiary structure.


Assuntos
Dinoprostona/biossíntese , Febre/imunologia , Febre/metabolismo , Interferon Tipo I/efeitos adversos , Receptores Opioides/metabolismo , Animais , Sítios de Ligação/fisiologia , Temperatura Corporal/imunologia , AMP Cíclico/metabolismo , Interferon Tipo I/genética , Interferon Tipo I/farmacologia , Masculino , Mutagênese Sítio-Dirigida , Estrutura Terciária de Proteína/genética , Estrutura Terciária de Proteína/fisiologia , Ratos , Ratos Sprague-Dawley , Receptores Opioides/fisiologia , Proteínas Recombinantes , Reto/imunologia , Reto/fisiologia
13.
Life Sci ; 72(22): 2533-42, 2003 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-12650862

RESUMO

Many stimulants, including bradykinin (BK), can induce increase in [Ca(2+)](i) in PC12 cells. Bradykinin induces an increase in [Ca(2+)](i) via intracellular Ca(2+) release and extracellular Ca(2+) influx through the transduction of G protein, but not through voltage-sensitive calcium channels. In this experiment, We analyzed how corticosterone (Cort) influences BK-induced intracellular Ca(2+) release and extracellular Ca(2+) influx, and further studied the mechanism of glucocorticoid's action. To dissociate the intracellular Ca(2+) release and extracellular Ca(2+) influx induced by BK, the Ca(2+)-free/Ca(2+)- reintroduction protocol was used. The results were as follows: (1) The Ca(2+) influx induced by BK could be rapidly inhibited by Cort, but intracellular Ca(2+) release could not be affected significantly. (2) The inhibitory effect of Cort-BSA (BSA -conjugated Cort) on Ca(2+) influx induced by BK was the same as the effect of free Cort. (3) Protein kinase C (PKC) activator (phorbol 12-myristate 13-acetate) could mimic and PKC inhibitor Gö6976 could reverse the inhibitory effect of Cort. (4) There was no inhibitory effect of Cort on Ca(2+) influx induced by BK when pretreated with pertussis toxin. The results suggested, for the first time, that Cort might act via a putative membrane receptor and inhibit the Ca(2+) influx induced by BK through the pertussis toxin -sensitive G protein-PKC pathway.


Assuntos
Bradicinina/antagonistas & inibidores , Cálcio/metabolismo , Glucocorticoides/farmacologia , Proteína Quinase C/metabolismo , Animais , Bradicinina/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Carbazóis/farmacologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Proteínas de Ligação ao GTP/metabolismo , Indóis/farmacologia , Células PC12 , Toxina Pertussis/farmacologia , Proteína Quinase C/antagonistas & inibidores , Ratos , Acetato de Tetradecanoilforbol/farmacologia , Tapsigargina/farmacologia , ômega-Conotoxinas/farmacologia
14.
Biochim Biophys Acta ; 1591(1-3): 21-7, 2002 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-12183051

RESUMO

We report here a new example in which glucocorticoids (GCs) acted in a rapid, nongenomic way. In rat B103 neuroblastoma cells, 5-hydroxytryptamine (5-HT) was found to evoke an immediate rise in intracellular free calcium concentration ([Ca(2+)](i)). Pre-incubation of B103 cells for 5 min with corticosterone (B) or bovine serum albumin-conjugated corticosterone (B-BSA) concentration-dependently (10(-4)-10(-8) M) inhibited the peak increments in [Ca(2+)](i). Cortisol and dexamethasone had a similar effect, while deoxycorticosterone and cholesterol were ineffective. This rapid inhibitory effect of corticosterone could be mimicked by protein kinase C (PKC) activator phorbol 12-myristate 13-acetate (PMA) and abolished completely by PKC inhibitors Ro31-8220 or GF-109203X. Neither pertussis toxin (PTX) nor nuclear GC receptor (GR) antagonist RU38486 influenced the rapid action of B. Our results suggest that GCs can modulate the 5-HT-induced Ca(2+) response in B103 cells in a membrane-initiated, nongenomic, and PKC-dependent manner.


Assuntos
Cálcio/metabolismo , Glucocorticoides/farmacologia , Neuroblastoma/metabolismo , Serotonina/farmacologia , Animais , Interações Medicamentosas , Ratos , Transdução de Sinais , Células Tumorais Cultivadas
15.
Acta Pharmacol Sin ; 23(6): 490-6, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12060521

RESUMO

AIM: To investigate the mechanism underlying the norepinephrine-induced elevation in intracellular calcium concentration ([Ca2+]i) in C6 glioma cells. METHODS: Measurement of [Ca2+]i was carried out using the dual-wavelength fluorescence method with fura-2 as the indicator. RESULTS: Norepinephrine was found to induce concentration-dependent increases in [Ca2+ ]i through alpha1-adrenoreceptors. The [Ca2+]i elevations were extracellular-calcium independent and not influenced by the treatment of pertussis toxin. Pretreatments with either U73122 or thapsigargin abolished the subsequent cellular calcium responses to norepinephrine. Preincubation with phorbol 12-myristate 13-acetate (PMA) significantly reduce d the [Ca2+]i elevations, while protein kinase C inhibitors Ro31-8220 or GF-109203X completely blocked the inhibitory action of PMA. However, drugs either activating or inhibiting the function of protein kinase A had no effect on the [Ca2+]i elevations. CONCLUSION: Norepinephrine induces calcium mobilization from internal stores by activation of phospholipase C in C6 cells. The [Ca2+]i elevation is negatively regulated by the activation of protein kinase C.


Assuntos
Cálcio/metabolismo , Glioma/metabolismo , Norepinefrina/farmacologia , Proteína Quinase C/metabolismo , Animais , Transporte Biológico Ativo , Fura-2 , Glioma/patologia , Ratos , Receptores Adrenérgicos alfa/metabolismo , Células Tumorais Cultivadas
16.
Neuroreport ; 13(8): 1089-94, 2002 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-12060815

RESUMO

In this study, membrane depolarization and multiple neurotransmitters (5-HT, acetylcholine, histamine, norepinephrine, epinephrine, glutamate, and ATP) were tested for the ability to elevate the intracellular free Ca2+ concentration ([Ca2+]i) in mouse HT4 neuroblastoma cells. Apart from ATP, none of the treatments gave rise to a detectable Ca2+ response, no matter whether the cells were subjected to temperature-induced neuronal differentiation. Our results provide pharmacological evidence for the co-existence in HT4 cells of both P2X and P2Y receptors, the activation of which by ATP led to Ca2+ influx and Ca2+ release, respectively. The P2Y receptor was found to couple to more than one type of G protein in the signaling pathway, causing the activation of phospholipase C (PLC) and Ca2+ mobilization from intracellular stores. cAMP-dependent protein kinase (PKA) and protein kinase C (PKC) attenuated ATP-evoked [Ca2+]i elevations in different ways. However, no correlation was identified between neuronal differentiation and the ATP-evoked Ca2+ responses in HT4 cells. This work indicates that HT4 cells can serve as a good model to study P2 purinoceptor-associated signaling pathways.


Assuntos
Trifosfato de Adenosina/metabolismo , Sinalização do Cálcio/fisiologia , Cálcio/metabolismo , Líquido Intracelular/metabolismo , Neurônios/metabolismo , Receptores Purinérgicos P2/metabolismo , Transdução de Sinais/fisiologia , Regulação para Cima/fisiologia , Trifosfato de Adenosina/farmacologia , Animais , Sinalização do Cálcio/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Líquido Intracelular/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Camundongos , Modelos Biológicos , Neuroblastoma , Neurônios/efeitos dos fármacos , Neurotransmissores/metabolismo , Neurotransmissores/farmacologia , Inibidores de Proteínas Quinases , Proteínas Quinases/metabolismo , Receptores Purinérgicos P2/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Células Tumorais Cultivadas , Regulação para Cima/efeitos dos fármacos , Fatores de Virulência de Bordetella/farmacologia
17.
Artigo em Chinês | MEDLINE | ID: mdl-21179840

RESUMO

AIM: To analyse the mechanism of corticosterone on the elevation of cytosolic free calcium ([Ca2+]i) induced by high-K+ in pheochromocytoma PC12 cells, METHODS: The [Ca2+]i was real-time checked by fluorescence image system. RESULTS: (1) When the cells were preincubated at 37 degrees C for 5 min in the presence of various concentration corticosterone and stimulated with 55 mmol/L KCl , an inhibitory effect of corticosterone on delta[Ca2+]i was observed in a concentration-dependent manner. (2) When PC12 cells were preincubated with various concentration of B-BSA at 37 degrees C for 5 min and stimulated with 55 mmol/L KCl, an inhibitory effect of B-BSA on delta[Ca2+]i was observed, which is also concentration-dependent manner. (3) The inhibitory effect of corticosterone and B-BSA could not be antagonized by RU38486 at 10(-4) mol/L. (4) cycloheximide could not block the inhibitory effect of corticosterone after pretreating cells at 10(-5) mol/L at 37 degrees C for 3 hours. CONCLUSION: It is obvious that the locus of corticosterone action is on the plasmic membrane. The inhibitory effect of corticosterone is independent of protein synthesis and intracellular glucocorticoid receptor. The effect of corticosterone on [Ca2+]i is nongenomic action in PC12 cells.


Assuntos
Cálcio/metabolismo , Corticosterona/farmacologia , Potássio/farmacologia , Animais , Células PC12/efeitos dos fármacos , Ratos
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