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1.
Cell Chem Biol ; 28(2): 169-179.e7, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33096051

RESUMO

Sterol regulatory element-binding proteins (SREBPs) are master transcriptional regulators of the mevalonate pathway and lipid metabolism and represent an attractive therapeutic target for lipid metabolic disorders. SREBPs are maintained in the endoplasmic reticulum (ER) in a tripartite complex with SREBP cleavage-activating protein (SCAP) and insulin-induced gene protein (INSIG). When new lipid synthesis is required, the SCAP-SREBP complex dissociates from INSIG and undergoes ER-to-Golgi transport where the N-terminal transcription factor domain is released by proteolysis. The mature transcription factor translocates to the nucleus and stimulates expression of the SREBP gene program. Previous studies showed that dipyridamole, a clinically prescribed phosphodiesterase (PDE) inhibitor, potentiated statin-induced tumor growth inhibition. Dipyridamole limited nuclear accumulation of SREBP, but the mechanism was not well resolved. In this study, we show that dipyridamole selectively blocks ER-to-Golgi movement of the SCAP-SREBP complex and that this is independent of its PDE inhibitory activity.


Assuntos
Dipiridamol/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipogênese/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo , Animais , Células CHO , Linhagem Celular , Cricetulus , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Ligação a Elemento Regulador de Esterol/genética
3.
J Acquir Immune Defic Syndr ; 85(5): 665-669, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33177477

RESUMO

BACKGROUND: We had previously conducted a double-blind, randomized placebo-controlled, partial cross-over trial showing that 12 weeks of dipyridamole decreased CD8 T-cell activation among treated HIV(+) individuals by increasing extracellular adenosine levels. METHODS: In this substudy, rectosigmoid biopsies were obtained from 18 participants (9 per arm), to determine whether 12 weeks of dipyridamole affects mucosal immune cells. Participants randomized to placebo were then switched to dipyridamole for 12 weeks while the treatment arm continued dipyridamole for another 12 weeks. We evaluated T-cell frequencies and plasma markers of microbial translocation and intestinal epithelial integrity. Linear regression models on log-transformed outcomes were used for the primary 12-week analysis. RESULTS: Participants receiving dipyridamole had a median 70.2% decrease from baseline in regulatory T cells (P = 0.007) and an 11.3% increase in CD8 T cells (P = 0.05). There was a nonsignificant 10.80% decrease in plasma intestinal fatty acid binding protein levels in the dipyridamole arm compared with a 9.51% increase in the placebo arm. There were no significant differences in plasma levels of ß-D-glucan. In pooled analyses, there continued to be a significant decrease in regulatory T cells (-44%; P = 0.004). There was also a trend for decreased CD4 and CD8 T-cell activation. CONCLUSION: Increasing extracellular adenosine levels using dipyridamole in virally suppressed HIV (+) individuals on antiretroviral therapy can affect regulation of gut mucosal immunity.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Dipiridamol/farmacologia , Infecções por HIV/tratamento farmacológico , Mucosa Intestinal/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos , Adenosina/metabolismo , Biópsia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Estudos Cross-Over , Feminino , Citometria de Fluxo , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade
4.
Proc Natl Acad Sci U S A ; 117(44): 27381-27387, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33051297

RESUMO

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global crisis. There is no therapeutic treatment specific for COVID-19. It is highly desirable to identify potential antiviral agents against SARS-CoV-2 from existing drugs available for other diseases and thus repurpose them for treatment of COVID-19. In general, a drug repurposing effort for treatment of a new disease, such as COVID-19, usually starts from a virtual screening of existing drugs, followed by experimental validation, but the actual hit rate is generally rather low with traditional computational methods. Here we report a virtual screening approach with accelerated free energy perturbation-based absolute binding free energy (FEP-ABFE) predictions and its use in identifying drugs targeting SARS-CoV-2 main protease (Mpro). The accurate FEP-ABFE predictions were based on the use of a restraint energy distribution (RED) function, making the practical FEP-ABFE-based virtual screening of the existing drug library possible. As a result, out of 25 drugs predicted, 15 were confirmed as potent inhibitors of SARS-CoV-2 Mpro The most potent one is dipyridamole (inhibitory constant Ki = 0.04 µM) which has shown promising therapeutic effects in subsequently conducted clinical studies for treatment of patients with COVID-19. Additionally, hydroxychloroquine (Ki = 0.36 µM) and chloroquine (Ki = 0.56 µM) were also found to potently inhibit SARS-CoV-2 Mpro We anticipate that the FEP-ABFE prediction-based virtual screening approach will be useful in many other drug repurposing or discovery efforts.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Reposicionamento de Medicamentos , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , COVID-19 , Cloroquina/farmacologia , Proteases 3C de Coronavírus , Infecções por Coronavirus/tratamento farmacológico , Cisteína Endopeptidases , Dipiridamol/farmacologia , Humanos , Hidroxicloroquina/farmacologia , Simulação de Acoplamento Molecular , Estrutura Molecular , Pandemias , Pneumonia Viral/tratamento farmacológico , SARS-CoV-2
5.
Mol Oncol ; 14(10): 2533-2545, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32749766

RESUMO

Dipyridamole, an antiplatelet drug, has been shown to synergize with statins to induce cancer cell-specific apoptosis. However, given the polypharmacology of dipyridamole, the mechanism by which it potentiates statin-induced apoptosis remains unclear. Here, we applied a pharmacological approach to identify the activity of dipyridamole specific to its synergistic anticancer interaction with statins. We evaluated compounds that phenocopy the individual activities of dipyridamole and assessed whether they could potentiate statin-induced cell death. Notably, we identified that a phosphodiesterase (PDE) inhibitor, cilostazol, and other compounds that increase intracellular cyclic adenosine monophosphate (cAMP) levels potentiate statin-induced apoptosis in acute myeloid leukemia and multiple myeloma cells. Additionally, we demonstrated that both dipyridamole and cilostazol further inhibit statin-induced activation of sterol regulatory element-binding protein 2, a known modulator of statin sensitivity, in a cAMP-independent manner. Taken together, our data support that PDE inhibitors such as dipyridamole and cilostazol can potentiate statin-induced apoptosis via a dual mechanism. Given that several PDE inhibitors are clinically approved for various indications, they are immediately available for testing in combination with statins for the treatment of hematological malignancies.


Assuntos
AMP Cíclico/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Neoplasias/patologia , Inibidores de Fosfodiesterase/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cilostazol/farmacologia , Dipiridamol/farmacologia , Sinergismo Farmacológico , Humanos , Hidrólise , Modelos Biológicos , Esteróis/metabolismo
6.
Cells ; 9(8)2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32824700

RESUMO

Blood-derived microRNA signatures have emerged as powerful biomarkers for predicting and diagnosing cardiovascular disease, cancer, and metabolic disorders. Platelets and platelet-derived microvesicles are a major source of microRNAs. We have previously shown that the inappropriate anticoagulation and storage of blood samples causes substantial platelet activation that is associated with the release of platelet-stored molecules into the plasma. However, it is currently unclear if circulating microRNA levels are affected by artificial platelet activation due to suboptimal plasma preparation. To address this issue, we used a standardized RT-qPCR test for 12 microRNAs (thrombomiR®, TAmiRNA GmbH, Vienna, Austria) that have been associated with cardiovascular and thrombotic diseases and were detected in platelets and/other hematopoietic cells. Blood was prevented from coagulating with citrate-theophylline-adenosine-dipyridamole (CTAD), sodium citrate, or ethylenediaminetetraacetic acid (EDTA) and stored for different time periods either at room temperature or at 4 °C prior to plasma preparation and the subsequent quantification of microRNAs. We found that five microRNAs (miR-191-5p, miR-320a, miR-21-5p, miR-23a-3p, and miR-451a) were significantly increased in the EDTA plasma. Moreover, we observed a time-dependent increase in plasma microRNAs that was most pronounced in the EDTA blood stored at room temperature for 24 h. Furthermore, significant correlations between microRNA levels and plasma concentrations of platelet-stored molecules pointed towards in vitro platelet activation. Therefore, we strongly recommend to (i) use CTAD as an anticoagulant, (ii) process blood samples as quickly as possible, and (iii) store blood samples at 4 °C whenever immediate plasma preparation is not feasible to generate reliable data on blood-derived microRNA signatures.


Assuntos
Anticoagulantes/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Coleta de Amostras Sanguíneas/métodos , Dipiridamol/farmacologia , Ácido Edético/farmacologia , MicroRNAs/sangue , MicroRNAs/genética , Citrato de Sódio/farmacologia , Adulto , Biomarcadores/sangue , Doadores de Sangue , Plaquetas/metabolismo , Feminino , Humanos , Masculino , Ativação Plaquetária/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Temperatura
7.
Sci Rep ; 10(1): 12135, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32699337

RESUMO

While the patency of vascular access is essential for hemodialysis patients, optimal pharmaceutical treatment to maintain arteriovenous fistula (AVF) patency remains lacking. As cardiovascular diseases are highly prevalent in patients with end-stage renal disease, various cardiovascular medications have also been used to maintain AVF patency. However, previous studies revealed inconsistent therapeutic effects and a comprehensive evaluation of this issue is needed. The present retrospective, longitudinal cohort study included patients receiving successful AVF creation. The evaluated cardiovascular medications included antiplatelet agents, antihypertensive agents, nitrates and nitrites, statins, dipyridamole, and pentoxifylline. The outcome was AVF primary patency. All laboratory data and medication profiles were recorded at baseline and followed at 3-month interval, until the end of the 2-year study period. Cox proportional regression model with time-dependent covariates was used to evaluate the risk for AVF patency loss. A total of 349 patients were included in the present study, in which 57% were men and the mean age was 65 ± 14 years. Among the included patients, 40% used antiplatelet agents, 27% used dipyridamole and 36% used statins at baseline. Of all the evaluated cardiovascular medications, only dipyridamole showed significant association with a higher risk for loss of AVF patency. To evaluate the effect of combination of antiplatelet agents and dipyridamole, the patients were classified into four groups, I: combine use of antiplatelet agents and dipyridamole, II: antiplatelet only, III: dipyridamole only; IV: none of both were used. Of the four groups, group IV exhibited highest AVF patency (52.4%), which was followed by group III (42.7%), group II (40%), and group I (28.6%), respectively. Compared with group IV, only group I showed a significantly higher risk for AVF patency loss. None of the cardiovascular medications evaluated in the present study showed a beneficial effect on AVF patency. Furthermore, dipyridamole showed an association with a higher risk of AVF patency loss. We do not suggest a beneficial effect of dipyridamole on maintaining AVF patency, particularly in combination with antiplatelet agents.


Assuntos
Fístula Arteriovenosa/etiologia , Dipiridamol/efeitos adversos , Inibidores da Agregação Plaquetária/efeitos adversos , Idoso , Fístula Arteriovenosa/diagnóstico , Doença da Artéria Coronariana/tratamento farmacológico , Dipiridamol/farmacologia , Dipiridamol/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Falência Renal Crônica/patologia , Falência Renal Crônica/terapia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico , Modelos de Riscos Proporcionais , Diálise Renal , Estudos Retrospectivos , Fatores de Risco , Grau de Desobstrução Vascular/efeitos dos fármacos
8.
J Plast Surg Hand Surg ; 54(4): 240-247, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32331511

RESUMO

Ischemic necrosis has been most dreaded complication of flap reconstruction. Therefore, researchers have tried to improvise modalities to prevent or treat it since the onset of flap surgery. So far these researches have failed to identify a pharmacological therapy equally effective as surgical delay in augmenting skin flap viability. In the path of search for this substance, dipyridamole attracted our attention as an antiaggregant agent. Put together with pathophysiological mechanisms underlying ischemic flap necrosis, we concluded dipyridamole might have beneficial effect on survival of skin flaps. In this research random pattern dorsal rat skin flap model of McFarlane is used. Subjects are separated in a randomized fashion between two groups. Experiment group is given dipyridamole with a dose of 20 mg/kg twice daily. Control group is given same amount of saline. At seventh day viability of skin flaps is assessed and compared between groups. Also on 7th day, pathologic specimens are obtained and evaluated histopathologically in terms of neutrophil and lymphocyte infiltration, edema and fibrosis. Necrosis percentage in experiment group is found to be significantly lower than that of control group (p < 0.01*). Neutrophil infiltration and edema found to be significantly lower in dipyridamole group (p < 0.05*). No significant difference is observed in lymphocyte infiltration and fibrosis. Dipyridamole is shown in this research to be effective in augmenting viability of random pattern skin flaps in rats. Nevertheless, more extensive researches are needed to fully determine its precise mechanism, side effects and appropriate doses.


Assuntos
Dipiridamol/farmacologia , Sobrevivência de Enxerto/efeitos dos fármacos , Transplante de Pele , Retalhos Cirúrgicos/patologia , Vasodilatadores/farmacologia , Animais , Masculino , Necrose/prevenção & controle , Complicações Pós-Operatórias/patologia , Distribuição Aleatória , Ratos , Ratos Wistar
9.
Biosci Rep ; 40(3)2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32124923

RESUMO

Ginkgo leaf extract and dipyridamole injection (GLED), a kind of Chinese herbal medicine preparation, has been considered as a promising supplementary treatment for chronic cor pulmonale (CCP). Although an analysis of the published literature has been performed, the exact effects and safety of GLED have yet to be systematically investigated. Therefore, a wide-ranging systematic search of electronic databases from which to draw conclusions was conducted. All randomized controlled trials concerning the GLED plus conventional treatments for CCP were selected in the present study. Main outcomes were treatment efficacy, blood gas and hemorrheology indexes, and adverse events. Data from 28 trials with 2457 CCP patients were analyzed. The results indicated that, compared with conventional treatments alone, the combination of conventional treatments with GLED obviously improved the markedly effective rate (RR = 1.44, 95% CI = 1.31-1.58, P < 0.00001) and total effective rate (RR = 1.28, 95% CI = 1.18-1.38, P < 0.00001). Moreover, the hemorrheology (PaO2, P < 0.00001; PaCO2, P < 0.00001; SaO2, P < 0.00001; pH value, P = 0.05) and blood gas indexes (PV, WBHSV, WBMSV, WBLSV, hematocrit and FBG, P < 0.01) of CCP patients were also significantly ameliorated after the combined therapy. The frequency of adverse events did not differ significantly between the two groups (P > 0.05). In summary, evidence from the meta-analysis suggested that the combination of conventional treatments and GLED appeared to be effective and relatively safe for CCP. Therefore, GLED mediated therapy could be recommended as an adjuvant treatment for CCP.


Assuntos
Dipiridamol/farmacologia , Extratos Vegetais/farmacologia , Doença Cardiopulmonar/tratamento farmacológico , Doenças Cardiovasculares/tratamento farmacológico , Doença Crônica , Dipiridamol/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Ginkgo biloba/metabolismo , Humanos , Hipertensão Pulmonar/tratamento farmacológico , Extratos Vegetais/metabolismo , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
10.
Pediatr Transplant ; 24(3): e13689, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32157785

RESUMO

BACKGROUND: Relative contraindications to adenosine use have included heart transplant and dipyridamole. We previously demonstrated the safety and efficacy of adenosine-induced atrioventricular (AV) block in healthy young heart transplant recipients while suspending dipyridamole therapy (dual antiplatelet agent). This prospective follow-up study evaluated the safety and efficacy of adenosine use in the same cohort of heart transplant recipients while on dipyridamole. METHODS: Adenosine was incrementally dosed until AV block occurred (maximum 200 mcg/kg up to 12 mg). The primary outcome was clinically significant asystole (≥12 seconds). Secondary outcomes included maximal adenosine dose, AV block duration, dysrhythmias, and clinical symptoms. Outcomes were compared to the parent study. RESULTS: Thirty of 39 eligible patients (5-24 years) were tested. No patient (0%, CI 0%-8%) experienced clinically significant asystole. AV block occurred in 29/30 patients (97%, CI 86%-100%). The median dose causing AV block was 50mcg/kg (vs 100 mcg/kg off dipyridamole; P = .011). Seventeen patients (57%, CI 39%-72%) required less adenosine to achieve AV block on dipyridamole; six (20%) required more. AV block occurred at doses ≥25 mcg/kg in all patients. In pairwise comparison to prior testing off dipyridamole, no significant change occurred in AV block duration, frequency of cardiac ectopy, or incidence of reported symptoms. No atrial fibrillation/flutter occurred. CONCLUSIONS: AV block often occurs at twofold lower adenosine doses in healthy young heart transplant recipients taking oral dipyridamole, compared with previous testing of this cohort off dipyridamole. Results suggest that initial dosing of 25 mcg/kg (maximum 0.8 mg) with stepwise escalation poses low risk of prolonged asystole on dipyridamole.


Assuntos
Adenosina/administração & dosagem , Antiarrítmicos/administração & dosagem , Bloqueio Atrioventricular/induzido quimicamente , Dipiridamol/administração & dosagem , Transplante de Coração , Complicações Pós-Operatórias/tratamento farmacológico , Taquicardia Supraventricular/tratamento farmacológico , Adenosina/farmacologia , Adenosina/uso terapêutico , Adolescente , Antiarrítmicos/farmacologia , Antiarrítmicos/uso terapêutico , Criança , Pré-Escolar , Dipiridamol/farmacologia , Dipiridamol/uso terapêutico , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos , Taquicardia Supraventricular/etiologia , Adulto Jovem
11.
Ann Biol Clin (Paris) ; 78(1): 27-34, 2020 02 01.
Artigo em Francês | MEDLINE | ID: mdl-32108577

RESUMO

Unfractionated heparin (UFH) is the main anticoagulante used in intensive care unit. The anticoagulant effect is monitored by activated partial thrombin time (aPTT) and anti-Xa activity (anti-Xa) measurement. However, delayed centrifugation induces platelet factor 4 (PF4) release and anti-Xa decrease. Several studies have concluded that aPTT and anti-Xa measurement should be performed within 2 hours in citrated anticoagulant but may be delayed longer in citrate theophylline adenosine and dypiridamol (CTAD) anticoagulant. The objective of this study was to compare the stability of both aPTT and anti-Xa in citrate and CTAD samples, and to determine the effect of delayed centrifugation on both aPTT, anti-Xa results, and PF4 release in citrate samples only. METHODS: aPTT and anti-Xa were measured in citrate and CTAD anticoagulant samples from 93 patients. Delayed centrifugation was performed in citrate samples from 31 additional patients, with hourly aPTT and anti-Xa measurement from 1 to 6 hours. In 14 of these last patients, PF4 release was also evaluated with Human CXCL4/PF4 Quantikine ELISA Kit. RESULTS: We observed a significant correlation between citrate and CTAD anticoagulant for aPTT (r2=0.94) and anti-Xa (r2=0.95). With Bland-Altman correlation, a minor bias was observed for anti-Xa (-0.025±0.041). Delayed centrifugation in citrated anticoagulant showed an excellent concordance from 1 to 4 hours for aPTT (-4.0±5.3 s) and anti-Xa (1.10-9±0.058 UI/mL) measurements. Moreover, PF4 release was not different between 1 hour (31.5±14.7 ng/mL) and 4 hours (33.8±11.8 ng/mL). CONCLUSION: We have demonstrated that anti-Xa measurement for unfractionated heparin should be done 4 hours in citrated plasma and that CTAD was not better than citrate. However, these initial findings require confirmation using other aPTT and calibrated anti-Xa assays.


Assuntos
Anticoagulantes/farmacologia , Coleta de Amostras Sanguíneas/métodos , Monitoramento de Medicamentos/métodos , Heparina/uso terapêutico , Adenosina/química , Adenosina/farmacologia , Anticoagulantes/química , Anticoagulantes/uso terapêutico , Testes de Coagulação Sanguínea/métodos , Preservação de Sangue/métodos , Centrifugação/métodos , Fracionamento Químico/métodos , Ácido Cítrico/química , Ácido Cítrico/farmacologia , Dipiridamol/química , Dipiridamol/farmacologia , Fator Xa/metabolismo , Inibidores do Fator Xa/análise , Inibidores do Fator Xa/sangue , Heparina/análise , Humanos , Tempo de Tromboplastina Parcial , Teofilina/química , Teofilina/farmacologia , Tempo de Trombina , Fatores de Tempo
12.
Minerva Cardioangiol ; 68(3): 249-257, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32100982

RESUMO

BACKGROUND: A blunted heart rate reserve (HRR) during dipyridamole stress echocardiography (DSE) is a prognostically unfavorable sign of cardiac autonomic dysfunction. Short-term adjustments of heart rate (HR) are thought to rise from changes in neural input to the heart. DSE is applied in potential heart donors to rule out underlying coronary artery disease and left ventricular dysfunction. The aim of this study is to assess HRR during DSE in brain death. METHODS: We enrolled two groups: group 1 (N.=49, 22 men, 54.6±8.8 years) with patients in brain death enrolled in the nationwide marginal donor heart recruiting program; group 2 (N.=49, 18 men, 66.4±12.0 years) referred to DSE for suspected or known coronary artery disease. All underwent DSE (0.84 mg/kg in 6') by quality-controlled readers certified via web-based training (1487/CE Lazio-1). We assessed left ventricular contractile reserve (LVCR) as stress/rest ratio of force (systolic blood pressure/end-systolic volume). HRR was calculated as the peak/rest HR ratio from 12-lead EKG. RESULTS: The two study groups were similar for prevalence of inducible ischemia (4/49 vs. 9/49, P=NS). Group 1 showed higher resting HR (group 1: 88.1±15.5 bpm vs. group 2: 66.5±11.5 bpm, P<0.01) and similar peak HR (group 1: 94.7±15.3 bpm vs. group 2: 89.5±19.3 bpm, P=0.144), with blunted HRR (group 1: 1.08±0.10 bpm vs. group 2: 1.36±0.31 bpm, P<0.01). HRR was unrelated to LVCR. CONCLUSIONS: HRR is almost abolished and unrelated to LVCR in brain-dead patients during DSE. The modulation of neural input to the heart is essential to determine HRR, and plays no significant role in determining the inotropic response during DSE.


Assuntos
Dipiridamol/farmacologia , Teste de Esforço/métodos , Frequência Cardíaca/efeitos dos fármacos , Doadores de Tecidos , Idoso , Morte Encefálica , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/fisiopatologia , Ecocardiografia sob Estresse , Eletrocardiografia , Feminino , Transplante de Coração , Humanos , Masculino , Pessoa de Meia-Idade , Vasodilatadores/farmacologia , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/fisiopatologia
14.
Mol Cancer Ther ; 19(1): 135-146, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31554653

RESUMO

Both the MAPK pathway and mevalonate (MVA) signaling pathway play an increasingly significant role in the carcinogenesis of colorectal carcinoma, whereas the cross-talk between these two pathways and its implication in targeted therapy remains unclear in colorectal carcinoma. Here, we identified that HMGCS1 (3-hydroxy-3-methylglutaryl-CoA synthase 1), the rate-limiting enzyme of the MVA pathway, is overexpressed in colon cancer tissues and positively regulates the cell proliferation, migration, and invasion of colon cancer cells. In addition, HMGCS1 could enhance the activity of pERK independent of the MVA pathway, and the suppression of HMGCS1 could completely reduce the EGF-induced proliferation of colon cancer cells. Furthermore, we found that trametinib, a MEK inhibitor, could only partially abolish the upregulation of HMGCS1 induced by EGF treatment, while combination with HMGCS1 knockdown could completely reverse the upregulation of HMGCS1 induced by EGF treatment and increase the sensitivity of colon cancer cells to trametinib. Finally, we combined trametinib and dipyridamole, a common clinically used drug that could suppress the activity of SREBF2 (sterol regulatory element-binding transcription factor 2), a transcription factor regulating HMGCS1 expression, and identified its synergistic effect in inhibiting the proliferation and survival of colon cancer cells in vitro as well as the in vivo tumorigenic potential of colon cancer cells. Together, the current data indicated that HMGCS1 may be a novel biomarker, and the combination of targeting HMGCS1 and MEK might be a promising therapeutic strategy for patients with colon cancer.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Dipiridamol/uso terapêutico , Hidroximetilglutaril-CoA Sintase/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Piridonas/uso terapêutico , Pirimidinonas/uso terapêutico , Animais , Linhagem Celular Tumoral , Proliferação de Células , Dipiridamol/farmacologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Piridonas/farmacologia , Pirimidinonas/farmacologia , Transfecção
15.
Biochem Pharmacol ; 172: 113747, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31830468

RESUMO

In the last decade it has been recapitulated that receptor-ligand binding kinetics is a relevant additional parameter in drug discovery to improve in vivo drug efficacy and safety. The equilibrative nucleoside transporter-1 (ENT1, SLC29A1) is an important drug target, as transporter inhibition is a potential treatment of ischemic heart disease, stroke, and cancer. Currently, two non-selective ENT1 inhibitors (dilazep and dipyridamole) are on the market as vasodilators. However, their binding kinetics are unknown; moreover, novel, more effective and selective inhibitors are still needed. Hence, this study focused on the incorporation of binding kinetics for finding new and improved ENT1 inhibitors. We developed a radioligand competition association assay to determine the binding kinetics of ENT1 inhibitors with four chemical scaffolds (including dilazep and dipyridamole). The kinetic parameters were compared to the affinities obtained from a radioligand displacement assay. Three of the scaffolds presented high affinities with relatively fast dissociation kinetics, yielding short to moderate residence times (RTs) at the protein (1-44 min). While compounds from the fourth scaffold, i.e. draflazine analogues, also had high affinity, they displayed significantly longer RTs, with one analogue (4) having a RT of over 10 h. Finally, a label-free assay was used to evaluate the impact of divergent ENT1 inhibitor binding kinetics in a functional assay. It was shown that the potency of compound 4 increased with longer incubation times, which was not observed for draflazine, supporting the importance of long RT for increased target-occupancy and effect. In conclusion, our research shows that high affinity ENT1 inhibitors show a large variation in residence times at this transport protein. As a consequence, incorporation of binding kinetic parameters adds to the design criteria and may thus result in a different lead compound selection. Taken together, this kinetic approach could inspire future drug discovery in the field of ENT1 and membrane transport proteins in general.


Assuntos
Transportador Equilibrativo 1 de Nucleosídeo/antagonistas & inibidores , Transportador Equilibrativo 1 de Nucleosídeo/metabolismo , Piperazinas/farmacologia , Cardiotônicos/química , Cardiotônicos/farmacologia , Linhagem Celular Tumoral , Dilazep/química , Dilazep/farmacologia , Dipiridamol/farmacologia , Transportador Equilibrativo 1 de Nucleosídeo/química , Humanos , Estrutura Molecular , Piperazinas/química , Ligação Proteica , Ensaio Radioligante , Relação Estrutura-Atividade
16.
Cell ; 179(5): 1160-1176.e24, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31730855

RESUMO

Pediatric-onset colitis and inflammatory bowel disease (IBD) have significant effects on the growth of infants and children, but the etiopathogenesis underlying disease subtypes remains incompletely understood. Here, we report single-cell clustering, immune phenotyping, and risk gene analysis for children with undifferentiated colitis, Crohn's disease, and ulcerative colitis. We demonstrate disease-specific characteristics, as well as common pathogenesis marked by impaired cyclic AMP (cAMP)-response signaling. Specifically, infiltration of PDE4B- and TNF-expressing macrophages, decreased abundance of CD39-expressing intraepithelial T cells, and platelet aggregation and release of 5-hydroxytryptamine at the colonic mucosae were common in colitis and IBD patients. Targeting these pathways by using the phosphodiesterase inhibitor dipyridamole restored immune homeostasis and improved colitis symptoms in a pilot study. In summary, comprehensive analysis of the colonic mucosae has uncovered common pathogenesis and therapeutic targets for children with colitis and IBD.


Assuntos
Doenças Inflamatórias Intestinais/patologia , Doenças Inflamatórias Intestinais/terapia , Mucosa Intestinal/patologia , Antígenos CD/metabolismo , Apirase/metabolismo , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Morte Celular/efeitos dos fármacos , Microambiente Celular/efeitos dos fármacos , Criança , Estudos de Coortes , Colo/patologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Dipiridamol/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Predisposição Genética para Doença , Homeostase/efeitos dos fármacos , Humanos , Imunoglobulina G/sangue , Memória Imunológica , Inflamação/patologia , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/genética , Interferon Tipo I/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Metilprednisolona/farmacologia , Células Mieloides/efeitos dos fármacos , Células Mieloides/metabolismo
17.
Korean J Ophthalmol ; 33(5): 414-421, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31612651

RESUMO

PURPOSE: Phosphodiesterase (PDE) inhibitors increase matrix metalloproteinase (MMP) production by inhibiting re-uptake of adenosine and may potentiate nitric oxide (NO) activity. This study was performed to investigate the effects and mechanisms of PDE inhibitors on trabecular outflow in cultured human trabecular meshwork cells (HTMCs). METHODS: Primary HTMC cultures were exposed to 0, 20, and 50 µM dipyridamole (DPD) or theophylline (TPN). Permeability through the HTMC monolayer was assessed using carboxyfluorescein. The production of NO was assessed using the Griess assay and MMP-2 levels were measured via Western blotting. RESULTS: DPD significantly increased permeability accompanied with increased nitrite concentration and MMP-2 levels (all p < 0.05). TPN increased nitrite but did not affect permeability or MMP-2 levels significantly (p > 0.05). When treated with DPD and TPN together, both permeability and nitrite production were increased; however, MMP-2 levels showed no difference compared to DPD exposure alone (p > 0.05). CONCLUSIONS: DPD increased trabecular permeability accompanied with increased nitrite production and MMP-2 levels. PDE inhibitors may increase trabecular outflow by increasing MMP-2 levels and by potentiating NO activity through cyclic GMP in HTMC.


Assuntos
Adenosina/metabolismo , Dipiridamol/farmacologia , Metaloproteinases da Matriz/metabolismo , Óxido Nítrico/metabolismo , Teofilina/farmacologia , Malha Trabecular/metabolismo , Western Blotting , Células Cultivadas , Humanos , Metaloproteinases da Matriz/efeitos dos fármacos , Inibidores de Fosfodiesterase/farmacologia , Malha Trabecular/citologia , Malha Trabecular/efeitos dos fármacos
18.
Antiviral Res ; 172: 104615, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31580916

RESUMO

Epstein-Barr virus (EBV) is a widely distributed gamma-herpesvirus that has been associated with various cancers mainly from lymphocytic and epithelial origin. Although EBV-mediated oncogenesis has been associated with viral oncogenes expressed during latency, a growing set of evidence suggested that antiviral treatments directed against EBV lytic phase may contribute to prevent some forms of cancers, including EBV-positive Post-Transplant Lymphoproliferative Diseases. It is shown here that dipyridamole (DIP), a safe drug with favorable and broad pharmacological properties, inhibits EBV reactivation from B-cell lines. DIP repressed immediate early and early genes expression mostly through its ability to inhibit nucleoside uptake. Considering its wide clinical use, DIP repurposing could shortly be evaluated, alone or in combination with other antivirals, to treat EBV-related diseases where lytic replication plays a deleterious role.


Assuntos
Dipiridamol/farmacologia , Herpesvirus Humano 4/efeitos dos fármacos , Ativação Viral/efeitos dos fármacos , Antivirais/farmacologia , Linfócitos B/metabolismo , Linfócitos B/virologia , Linhagem Celular , DNA Viral/efeitos dos fármacos , Reposicionamento de Medicamentos , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Expressão Gênica/efeitos dos fármacos , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Humanos , Nucleosídeos/metabolismo , Latência Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
19.
J Orthop Res ; 37(12): 2499-2507, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31334868

RESUMO

There are over two million long bone defects treated in the United States annually, of which ~5% will not heal without significant surgical intervention. While autogenous grafting is the standard of care in simple defects, a customized scaffold for large defects in unlimited quantities is not available. Recently, a three-dimensionally (3D)-printed bioactive ceramic (3DPBC) scaffold has been successfully utilized in the of repair critical-sized (CSD) long bone defects in vivo. In this study, 3DPBC scaffolds were augmented with dipyridamole (DIPY), an adenosine A2A receptor (A2A R) indirect agonist, because of its known effect to enhance bone formation. CSD full thickness segmental defects (~11 mm × full thickness) defects were created in the radial diaphysis in New Zealand white rabbits (n = 24). A customized 3DPBC scaffold composed of ß-tricalcium phosphate was placed into the defect site. Groups included scaffolds that were collagen-coated (COLL), or immersed in 10, 100, or 1,000 µM DIPY solution. Animals were euthanized 8 weeks post-operatively and the radii/ulna-scaffold complex retrieved en bloc, for micro-CT, histological, and mechanical analysis. Bone growth was assessed exclusively within scaffold pores and evaluated by microCT and advanced reconstruction software. Biomechanical properties were evaluated utilizing nanoindentation to assess the newly regenerated bone for elastic modulus (E) and hardness (H). MicroCT reconstructions illustrated bone in-growth throughout the scaffold, with an increase in bone volume dependent on the DIPY dosage. The histological evaluation did not indicate any adverse immune response while revealing progressive remodeling of bone. These customized biologic 3DPBC scaffolds have the potential of repairing and regenerating bone. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2499-2507, 2019.


Assuntos
Regeneração Óssea , Dipiridamol/farmacologia , Impressão Tridimensional , Tecidos Suporte , Animais , Cerâmica , Feminino , Osteogênese , Coelhos , Microtomografia por Raio-X
20.
Plast Reconstr Surg ; 144(2): 358-370, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31348344

RESUMO

BACKGROUND: Alveolar clefts are traditionally treated with secondary bone grafting, but this is associated with morbidity and graft resorption. Although recombinant human bone morphogenetic protein-2 (rhBMP-2) is under investigation for alveolar cleft repair, safety concerns remain. Dipyridamole is an adenosine receptor indirect agonist with known osteogenic potential. This study compared dipyridamole to rhBMP-2 at alveolar cleft defects delivered using bioceramic scaffolds. METHODS: Skeletally immature New Zealand White rabbits underwent unilateral, 3.5 × 3.5-mm alveolar resection adjacent to the growing suture. Five served as negative controls. The remaining defects were reconstructed with three-dimensionally printed bioceramic scaffolds coated with 1000 µm of dipyridamole (n = 6), 10,000 µm of dipyridamole (n = 7), or 0.2 mg/ml of rhBMP-2 (n = 5). At 8 weeks, new bone was quantified. Nondecalcified histologic evaluation was performed, and new bone was evaluated mechanically. Statistical analysis was performed using a generalized linear mixed model and the Wilcoxon rank sum test. RESULTS: Negative controls did not heal, whereas new bone formation bridged all three-dimensionally printed bioceramic treatment groups. The 1000-µm dipyridamole scaffolds regenerated 28.03 ± 7.38 percent, 10,000-µm dipyridamole scaffolds regenerated 36.18 ± 6.83 percent (1000 µm versus 10,000 µm dipyridamole; p = 0.104), and rhBMP-2-coated scaffolds regenerated 37.17 ± 16.69 percent bone (p = 0.124 versus 1000 µm dipyridamole, and p = 0.938 versus 10,000 µm dipyridamole). On histology/electron microscopy, no changes in suture biology were evident for dipyridamole, whereas rhBMP-2 demonstrated early signs of suture fusion. Healing was highly cellular and vascularized across all groups. No statistical differences in mechanical properties were observed between either dipyridamole or rhBMP-2 compared with native bone. CONCLUSION: Dipyridamole generates new bone without osteolysis and early suture fusion associated with rhBMP-2 in skeletally immature bone defects.


Assuntos
Processo Alveolar/efeitos dos fármacos , Conservadores da Densidade Óssea/farmacologia , Proteína Morfogenética Óssea 2/farmacologia , Regeneração Óssea/efeitos dos fármacos , Dipiridamol/farmacologia , Tecidos Suporte , Fator de Crescimento Transformador beta/farmacologia , Processo Alveolar/lesões , Animais , Conservadores da Densidade Óssea/administração & dosagem , Proteína Morfogenética Óssea 2/administração & dosagem , Transplante Ósseo/métodos , Dipiridamol/administração & dosagem , Modelos Animais de Doenças , Microscopia Eletrônica de Varredura , Modelos Animais , Osteogênese/efeitos dos fármacos , Impressão Tridimensional , Coelhos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Fator de Crescimento Transformador beta/administração & dosagem , Microtomografia por Raio-X
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