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1.
Bioorg Med Chem Lett ; 86: 129234, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36905967

RESUMO

The discovery of a new naphthylisoquinoline alkaloid, dioncophyllidine E (4), from the tropical liana Ancistrocladus abbreviatus (Ancistrocladaceae) is described. Due to its rare 7,3'-coupling type, combined with the lack of an oxygen function at C-6, it is configurationally semi-stable at the biaryl axis, and thus occurs as a pair of slowly interconverting atropo-diastereomers, 4a and 4b. Its constitution was assigned mainly by 1D and 2D NMR. The absolute configuration at the stereocenter, C-3, was elucidated by oxidative degradation. The absolute axial configuration of the individual atropo-diastereomers was established by their HPLC resolution, combined with online electronic circular dichroism (ECD) investigations, providing nearly mirror-imaged LC-ECD spectra. These were assigned to the respective atropisomers by ECD comparison with a related, but configurationally stable alkaloid, ancistrocladidine (5). Dioncophyllidine E (4a/4b) exhibits a strong preferential cytotoxicity against PANC-1 human pancreatic cancer cells under nutrient-deprived conditions, with a PC50 value of 7.4 µM, suggesting its potential as an agent against pancreatic cancer.


Assuntos
Alcaloides , Antineoplásicos Fitogênicos , Antineoplásicos , Neoplasias Pancreáticas , Humanos , Estrutura Molecular , Alcaloides/farmacologia , Alcaloides/química , Antineoplásicos/uso terapêutico , Espectroscopia de Ressonância Magnética , Neoplasias Pancreáticas/tratamento farmacológico , Antineoplásicos Fitogênicos/química
2.
Bioconjug Chem ; 32(11): 2307-2317, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34379392

RESUMO

Peptide-based vaccines are composed of small, defined, antigenic peptide epitopes. They are designed to induce well-controlled immune responses. Multiple epitopes are often employed in these vaccines to cover strain variability of a pathogen. However, peptide epitopes cannot stimulate adequate immune responses on their own and require an adjuvant (immune stimulant) and/or delivery system. Here, we designed and synthesized a multiepitope vaccine candidate against Group A Streptococcus (GAS) composed of several B-cell epitopes (J8, PL1, and 88/30) derived from GAS M-protein, universal PADRE T-helper cell epitope, and a polyleucine self-adjuvanting unit. The vaccine components were conjugated together (using mercapto-maleimide and azide-alkyne Huisgen cycloaddition reactions) or delivered as a mixture. The conjugated multiepitope vaccine candidate self-assembled into small nanoparticles and chain-like aggregated nanoparticles (CLANs) that were able to induce the production of J8-, PL1-, and 88/30-specific antibodies in mice. The multiepitope conjugate and the physical mixture of conjugates bearing the individual epitopes produced similar nanoparticles and induced comparable immune responses. Hence, simple physical mixing can replace complex chemical conjugation to produce multiepitope nanoparticles with equivalent morphology and immunological efficacy. This greatly simplifies vaccine production.


Assuntos
Streptococcus pyogenes
3.
Support Care Cancer ; 29(8): 4885-4892, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33598734

RESUMO

OBJECTIVE: The aim of this meta-analysis was to evaluate the effectiveness of glutamine for preventing or treating moderate-to-severe oral mucositis induced by chemotherapy or radiation therapy in patients with cancer. METHODS: PubMed, Cochrane Library, and Embase were searched for eligible randomized controlled trials (RCTs) up to June 2020. The outcomes analyzed were oral mucositis (at all levels of severity). Data were pooled using the random-effects model and are expressed as risk ratios (RRs) and corresponding 95% confidence intervals (CIs). Heterogeneity was assessed and quantified using I2. RESULTS: Sixteen RCTs were included in this review. In this meta-analysis, compared with placebo, glutamine significantly reduced the incidence of grade 3 and 4 oral mucositis induced by chemotherapy or radiation therapy (RR, 0.53; 95% CI, 0.32-0.88). In subgroup analysis, oral glutamine administration (RR, 0.56; 95% CI, 0.34-0.92) and a medium or low daily dose of glutamine (RR, 0.58; 95% CI, 0.44-0.77; RR, 0.53; 95% CI, 0.28-0.94; respectively) decreased risk. Glutamine caused a borderline significant reduction in the risk of grade 3 and 4 oral mucositis induced by radiotherapy (RR, 0.75; 95% CI, 0.58-0.99) and especially in its prevention (RR, 0.51; 95% CI, 0.28-0.94). CONCLUSIONS: Glutamine significantly reduces the risk of oral mucositis during chemotherapy or radiation therapy. Furthermore, large prospective trials are required to support these findings.


Assuntos
Glutamina/uso terapêutico , Neoplasias/complicações , Estomatite/tratamento farmacológico , Glutamina/farmacologia , Humanos , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
J Cell Physiol ; 230(9): 2038-48, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25536014

RESUMO

Phosphodiesterase (PDE) inhibitors have been suggested as a possible candidate for the treatment of osteopenia, including osteoporosis. KMUP-1 is a novel xanthine derivative with inhibitory activities on the PDE 3, 4, and 5 iso-enzymes to suppress the degradation of cAMP and cGMP. This study aimed to investigate the effect of KMUP-1 on osteoblast differentiation and the underlying cellular and molecular mechanisms. Primary osteoblasts and osteoblastic MC3T3-E1 cells were examined. KMUP-1 enhanced alkaline phosphatase (ALP) activity and mineralization compared to untreated controls in primary osteoblasts and MC3T3-E1 cells. KMUP-1 also increased the mRNA expression of the osteoblastic differentiation markers, including collagen type 1a, ALP, osteocalcin, osteoprotegerin, BMP-2, and Runx2, a key transcription regulator for osteoblastic differentiation. The osteogenic effect of KMUP-1 was abolished by BMP signaling inhibitor, noggin. Furthermore, we found that KMUP-1 upregulated Smad1/5/8 phosphorylations with subsequent BRE-Luc activation confirmed by transient transfection assay. In addition, KMUP-1 inactivated glycogen synthase kinase-3ß (GSK-3ß), with associated nuclear translocation of ß-catenin. Co-treatment with H89 and KT5823, cAMP and cGMP pathway inhibitors, respectively, reversed the KMUP-1-induced activations of Smad1/5/8, ß-catenin, and Runx2. The findings demonstrate for the first time that KMUP-1 can promote osteoblast maturation and differentiation in vitro via BMP-2/Smad1/5/8 and Wnt/ß-catenin pathways. These effects are mediated, in part, by the cAMP and cGMP signaling. Thus, KMUP-1 may be a novel osteoblast activator and a potential new therapy for osteoporosis.


Assuntos
Proteína Morfogenética Óssea 2/biossíntese , Diferenciação Celular/efeitos dos fármacos , Piperidinas/administração & dosagem , Proteína Smad1/biossíntese , Proteína Smad5/biossíntese , Proteína Smad8/biossíntese , Xantinas/administração & dosagem , Animais , Proteína Morfogenética Óssea 2/genética , Calcificação Fisiológica , Linhagem Celular , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Camundongos , Osteoblastos/efeitos dos fármacos , RNA Mensageiro/biossíntese , Proteína Smad1/genética , Proteína Smad5/genética , Proteína Smad8/genética , Via de Sinalização Wnt
6.
Gen Hosp Psychiatry ; 89: 75-83, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38824832

RESUMO

BACKGROUND: Evidence suggests that inflammatory processes play a role in the pathophysiology of schizophrenia. Statins exert anti-inflammatory and antioxidant effects and may be effective in improving the symptoms of schizophrenia. This study explored whether statins, as an adjunctive therapy, can alleviate the symptoms of schizophrenia. METHODS: PubMed, EMBASE, and the Cochrane Library were searched for articles published up to March 2023. The risk-of-bias tool for randomized trials was used to assess study quality. Two researchers independently assessed the risks of bias and extracted data. Pooled data on Positive and Negative Syndrome Scale (PANSS) scores were analyzed. A random-effects model was employed to calculate pooled effect sizes. Statistical heterogeneity across studies was assessed using the I2 statistic. All analyses were performed using RevMan5 and Comprehensive Meta-Analysis software. RESULTS: Nine trials enrolling 533 patients in total were included. Add-on statin therapy was found to be associated with a significantly better total PANSS score [standardized mean difference (SMD) = -0.42, 95% confidence interval (CI) -0.75 to -0.09, I2 = 72%; P = 0.01] and PANSS negative subscale score (SMD = -0.26, 95% CI -0.45 to -0.07, I2 = 0%; P = 0.009) in comparison with placebo. However, add-on statin therapy did not appear to improve scores for the PANSS positive and general subscales at the study-defined endpoint (6-24 weeks). CONCLUSIONS: Our meta-analysis indicates that adjunctive statin therapy may confer benefits in ameliorating PANSS negative and total scores. It needs more solid data to confirm the results are related to clinical improvement and functioning.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Esquizofrenia , Humanos , Esquizofrenia/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Quimioterapia Combinada , Antipsicóticos/administração & dosagem , Antipsicóticos/farmacologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-21785641

RESUMO

San-Huang-Xie-Xin-Tang (SHXT) is a traditional Chinese medication consisting of three herbs, namely Coptidis rhizome, Scutellariae radix and Rhei rhizome. This study aimed to examine the cardioprotective effects of SHXT in a rat model of acute myocardial apoptosis induced by ischemia/reperfusion (I/R). Vehicle (intravenous saline) or SHXT (intravenous or oral) was administered prior to I/R (occlusion of left coronary artery for 45 min followed by reperfusion for 2 h). In the vehicle group, myocardial I/R caused myocardial infarction with increased plasma cardiac enzymes, severe arrhythmia and mortality. Myocardial apoptosis was induced by I/R as evidenced by DNA ladder and Bcl-2/Bax ratio. In the SHXT group, we found that SHXT significantly reduced plasma levels of cardiac enzymes, arrhythmia scores (from 5 ± 1 to 2 ± 1, P < .01) and mortality rate (from 53 to 0%, P < .01). In addition, pretreatment with intravenous SHXT reduced the infarct size dose-dependently when compared with the vehicle group (10 mg kg(-1): 14.0 ± 0.2 versus 44.5 ± 5.0%, and 30 mg kg(-1): 6.2 ± 1.2% versus 44.5 ± 5.0%, both P < .01). Similarly, oral administration of SHXT reduced the infarct size dose-dependently. Furthermore, SHXT markedly decreased the apoptosis induced by I/R with increased Bcl-2/Bax ratio. Finally, we found that SHXT counteracted the I/R-induced downstream signaling, resulting in increased myocardial eNOS expression and plasma nitrite, and decreased activation of ERK1/2, p38 and JNK. These data suggest that SHXT has cardioprotective effects against I/R-induced apoptosis, and that these effects are mediated, at least in part, by eNOS and MAPK pathways.

8.
Thorac Cancer ; 12(21): 2873-2885, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34545685

RESUMO

OBJECTIVE: Currently, several immune checkpoint inhibitors (ICIs) treatment for advanced non-small-cell lung cancer (NSCLC) have been investigated; their overall efficacy and safety remain unclear. METHODS: We searched electronic databases such as PubMed, EMBASE, and the Cochrane library. The randomized controlled trials (RCTs) that compared ICIs with or without chemotherapy to chemotherapy in advanced NSCLC. We collected and compaired thier parameters, including overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and treatment-related adverse events (TRAEs) of grade ≥3. RESULTS: A total of 15 RCTs involving 8869 patients with NSCLC were included. Pembrolizumab plus platinum-based chemotherapy had higher OS and PFS than platinum-based chemotherapy (hazard ratio [HR] 0.55, 95% CI 0.46-0.67; HR 0.54, 95% CI 0.41-0.70, respectively). Pembrolizumab plus platinum-based chemotherapy had higher ranked ORR than platinum-based chemotherapy (odds ratio [OR] 2.92, 95% CI 1.99-4.22). In terms of OS, atezolizumab, pembrolizumab plus platinum-based chemotherapy, and nivolumab plus ipilimumab ranked as the best treatments for patients with programmed death-ligand 1 (PD-L1) expression levels of ≥50%, 1-49%, and <1%, respectively. In terms of PFS, pembrolizumab plus platinum-based chemotherapy ranked as the best treatment for patients with any PD-L1 expression levels. However, ipilimumab plus platinum-based chemotherapy, nivolumab plus platinum-based chemotherapy, and atezolizumab plus platinum-based chemotherapy have higher TRAEs of grade ≥3 than platinum-based chemotherapy. CONCLUSIONS: Pembrolizumab plus platinum-based chemotherapy prevailed in rank in OS, PFS, and ORR benefit. The TRAEs of pembrolizumab plus platinum-based chemotherapy were more than ICI monotherapy and chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Humanos , Intervalo Livre de Progressão , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Toxicology ; 256(1-2): 13-24, 2009 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-19056458

RESUMO

In this research, we conducted an in vitro analysis to evaluate the prostate cancer cells response to labedipinedilol-A in order to determine the effect of this selective alpha(1)-adrenoceptor antagonist to suppress prostate cancer cell growth by affecting cell proliferation and apoptosis. Here, we report that treatment of androgen-sensitive (LNCaP) and androgen-insensitive (PC-3) prostate cancer cells with labedipinedilol-A inhibited cell proliferation in concentration-dependent and time-dependent manners. Moreover, norepinephrine-stimulated proliferation of both cell lines are markedly inhibited by labedipinedilol-A. The probable involvement of alpha(1)-adrenoceptors in this cellular response is suggested. Labedipinedilol-A-induced growth inhibition was associated with G(0)/G(1) arrest, and G(2)/M arrest depending upon concentrations. Cell cycle blockade was associated with reduced amounts of cyclin D1/2, cyclin E, Cdk2, Cdk4, and Cdk6 and increased levels of the Cdk inhibitory proteins (Cip1/p21 and Kip1/p27). In addition, labedipinedilol-A also induced apoptosis in PC-3 cells, as determined by using Hoechst 33342 staining, DNA fragmentation, and Annexin V staining assay. Furthermore, labedipinedilol-A triggered the mitochondrial apoptotic pathway, as indicated by increasing the expression of Bax, but decreasing the level of Bcl-2, resulting in mitochondrial membrane potential loss, cytochrome c release, and activation of caspase-9 and -3. We further investigated the role of MAPK cascades in the anti-proliferative and apoptosis effects of labedipinedilol-A, and confirmed that labedipinedilol-A could activate JNK1/2 but not p38 in both cell lines. Unlike JNK1/2, however, labedipinedilol-A treatment resulted in down-regulation of phospho-ERK1/2 expression. We concluded that labedipinedilol-A possessed the growth-suppressive and apoptotic effects on LNCaP and PC-3 cells by its alpha(1)-adrenoceptor blockade, and the apoptotic effects of labedipinedilol-A primarily through caspases and MAPKs mediated pathways.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1 , Antagonistas Adrenérgicos alfa/farmacologia , Anisóis/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Di-Hidropiridinas/farmacologia , Neoplasias da Próstata/patologia , Benzimidazóis , Western Blotting , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Corantes Fluorescentes , Humanos , Masculino , Potenciais da Membrana/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteína Oncogênica v-akt/genética , Proteína Oncogênica v-akt/metabolismo , Receptores Adrenérgicos alfa 1/metabolismo , Transdução de Sinais/efeitos dos fármacos
10.
Epilepsy Behav ; 11(3): 303-9, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17826356

RESUMO

An enriched environment can enhance brain recovery in animals with early-life status epilepticus (SE). The purpose of this study was to determine the effects of early-life SE on spatial memory and hippocampal extracellular signal-regulated kinase (ERK) level, and the possible therapeutic effects of the enriched environment. Rats were assigned randomly to four groups: (1) control rats (nonenriched control); (2) control rats housed in an enriched environment from Postnatal Day (P) 25 to P40 (enriched control); (3) rats in which SE was induced with lithium-pilocarpine (Li-PC) at P21 (nonenriched SE); and (4) rats in which SE was induced with Li-PC at P21 and then housed in an enriched environment from P25 to P40 (enriched SE). As adults, the rats underwent spatial learning and memory tests in the Morris water maze between P50 and P55. At P55, subsets of animals were evaluated for expression of hippocampal ERK1/2 phosphorylation immediately following completion of the Morris water maze. At ~P100, another set of animals was tested for seizure threshold. When studied as adults, only the nonenriched SE group had a spatial memory deficit. The nonenriched SE group also exhibited lower levels of phosphorylated ERK2 as compared with the nonenriched control, enriched control, and enriched SE groups. Both the nonenriched SE and enriched SE groups had reduced seizure thresholds as compared with the nonenriched control and enriched control groups. Results from this study demonstrate that an enriched environment improves spatial memory in rats subjected to early-life SE, possibly through upregulation of phosphorylated ERK2 in the hippocampus. However, an enriched environment has no effect on seizure threshold.


Assuntos
Cognição/fisiologia , Meio Ambiente , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Estado Epiléptico/fisiopatologia , Análise de Variância , Animais , Animais Recém-Nascidos , Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças , Hipocampo/enzimologia , Cloreto de Lítio , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Fosforilação/efeitos dos fármacos , Pilocarpina , Ratos , Ratos Sprague-Dawley , Comportamento Espacial/efeitos dos fármacos , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/patologia , Fatores de Tempo
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