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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 311: 124017, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38354677

RESUMO

Nanoparticles are a boon for humanity because of their improved functionality and unlimited potential applications. Considering this significance, the proposed study introduced a simple, fast and eco-friendly method for synthesis of fluorescent silver nanoparticles (Ag-NPs) using Panax Ginseng root extract as a reducing and capping agent. Synthesis of Ag-NPs was performed in one step within three minutes utilizing microwave irradiation. The resulting Ag-NPs were characterized using various microscopic and spectroscopic techniques such as, Transmission Electron Microscope (TEM), UV/Visible spectroscopy, Fourier Transform Infrared Spectroscopy(FTIR) and Energy Dispersive X-ray analysis (EDX). The prepared Ag-NPs, which act as a fluorescent nano-probe with an emission band at 416 nm after excitation at 331 nm, were used to assay nilvadipine (NLV) spectrofluorimetrically in its pharmaceutical dosage form with good sensitivity and reproducibility. The proposed study is based on the ability of NLV to quantitatively quench the native Ag-NPs fluorescence, forming a ground state complex as a result of static quenching and an inner filter mechanism. The suggested approach displayed a satisfactory linear relationship throughout a concentration range of 5.0 µM - 100.0 µM, with LOD and LOQ values of 1.18 µM and 3.57 µM, respectively. Validation of the suggested approach was examined in accordance with ICH recommendations. In addition, the anti-bacterial and anti-fungal activities of the prepared nanoparticles were investigated, and they demonstrated effective anti-microbial activities and opened a future prospective to combat future antibiotic resistance. Finally, in-vitro cytotoxicity assay of Ag-NPs against normal and cancerous human cell lines was studied using MTT assay. The results proved the potential use of the produced Ag-NPs as an adjunct to anticancer treatment or for drug delivery without significantly harming healthy human cells.


Assuntos
Antineoplásicos , Nanopartículas Metálicas , Nifedipino/análogos & derivados , Panax , Humanos , Prata/farmacologia , Prata/química , Corantes Fluorescentes/farmacologia , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Bactérias , Antibacterianos/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Testes de Sensibilidade Microbiana
2.
Biomed Chromatogr ; 36(1): e5244, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34528268

RESUMO

An experimental combination of analytical quality by design and green analytical chemistry approaches is introduced to develop an high-performance thin-layer chromatography (HPTLC) approach to quantify barnidipine hydrochloride in the pharmaceutical matrix. The analytical quality by design approach was introduced to green analytical chemistry to enhance protocol knowledge while ensuring efficiency and reducing environmental impacts, energy consumption and analyst visibility. This analytical approach was systematically addressed by exploring failure mode effect analysis, risk assessment and optimization design. Subsequently, a screening of primary variables was performed to select the aptest proportion of solvents in the mobile phase resulting from the principles of green analytical chemistry. Failure mode effect analysis and a risk assessment study were attempted to estimate the critical method parameters (CMPs). The influence of the CMPs on critical analytical attributes, i.e. retention factor and peak area, was assessed through a screening design. A response surface methodology was then executed for the critical analytical attributes as a concern of the determined CMPs, and the conditions for excellent resolution were determined using a desirability procedure. The established protocol was validated in compliance with the International Conference on Harmonization guideline Q2(R1) and showed excellent specificity and sensitivity.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Fina/métodos , Química Verde/métodos , Nifedipino/análogos & derivados , Limite de Detecção , Modelos Lineares , Nifedipino/análise , Reprodutibilidade dos Testes , Projetos de Pesquisa
3.
Future Med Chem ; 13(15): 1271-1283, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34137272

RESUMO

Background: A comprehensive approach to drug repositioning will be required to overcome translational hurdles and identify more neuroprotective drugs. Results & methods: Gene Set Enrichment Analysis was applied to identify related pathways and enriched genes. Candidate genes were optimized using ToppGene, ToppGenet and pBRIT. From the perspective of the local structures, gene-domain-substructure-drug relationships were constructed. Using the MCODE algorithm and K-means clustering, 31 functional subnetworks were obtained, and 252 drugs with proposed neuroprotective function were identified. Using computational analysis, 72 substructures with different scores were found to correspond to neuroprotective functions. The protective effects of benidipine and barnidipine were confirmed in vitro. Conclusion: The authors' research has great potential to discover more neuroprotective drugs and obtain more information regarding mechanisms of action and functional substructures.


Assuntos
Biologia Computacional/métodos , Reposicionamento de Medicamentos , AVC Isquêmico/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Algoritmos , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Di-Hidropiridinas/química , Di-Hidropiridinas/farmacologia , Di-Hidropiridinas/uso terapêutico , Descoberta de Drogas , Humanos , AVC Isquêmico/genética , AVC Isquêmico/patologia , Camundongos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Nifedipino/análogos & derivados , Nifedipino/química , Nifedipino/farmacologia , Nifedipino/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos
4.
Iran J Med Sci ; 46(2): 136-143, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33753958

RESUMO

Background: Mebudipine, a dihydropyridine calcium-channel blocker (CCB), shows greater time- and voltage-dependent inhibitory effects than nifedipine. Its significant negative chronotropic effects without having considerable negative inotropic properties may make it a suitable candidate for the pharmacotherapy of heart failure (HF). This study aimed to investigate the possible beneficial action of mebudipine in a rat model of HF. Methods: The present study carried out in the Department of Pharmacology at the Iran University of Medical Sciences during the years of 2009-2011. An experimental model of HF was induced in male Wistar rats using doxorubicin (DOX). The rats were divided into five groups with seven animals in each group: normal control group, DOX-induced HF control groups, and treatment groups. The animals were administered DOX for 15 days. A consistent deterioration occurred after a four-week rest period. The animals were then treated with intraperitoneal mebudipine (0.5 mg/kg) and intraperitoneal amlodipine (0.35 mg/kg), as well as an equal volume of distilled water for 15 days. The plasma levels of big endothelin-1 (BET-1), creatine kinase-myocardial band (CK-MB), lactate dehydrogenase (LDH), aspartate aminotransferase (AST), and alanine aminotransferase (ALT), as well as the clinical status (heart rate and blood pressure), were assessed before and after treatment. Statistical analysis was performed with SPSS software using parametric and nonparametric ANOVA. Results: Mebudipine and amlodipine reversed the increased plasma BET-1 values in the treated animals when compared with the HF control group (0.103 and 0.112 vs 0.231 pg/mL, respectively). The increased plasma levels of AST, ALT, CK-MB, and LDH were also reversed in the HF animals that received mebudipine or amlodipine. Conclusion: The administration of mebudipine to HF animals, akin to amlodipine, palliated the clinical and biochemical signs of the disease in the present study. The abstract was presented in the Iranian Congress of Physiology and Pharmacology as a poster and published in the Scientific Information Database as a supplement (2015; Vol 22).


Assuntos
Doxorrubicina/efeitos adversos , Insuficiência Cardíaca/etiologia , Nifedipino/análogos & derivados , Fatores de Proteção , Animais , Pressão Sanguínea/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio , Modelos Animais de Doenças , Coração/efeitos dos fármacos , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/tratamento farmacológico , Frequência Cardíaca/efeitos dos fármacos , Irã (Geográfico) , Nifedipino/farmacologia , Nifedipino/normas , Ratos , Ratos Wistar/fisiologia
5.
Turk Neurosurg ; 31(3): 310-317, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32091117

RESUMO

AIM: To evaluate the neuroprotective effects of benidipine hydrochloride on the cerebral cortex tissues in rats exposed to cerebral ischemia-reperfusion (I/R) injury. MATERIAL AND METHODS: Twenty-four male Wistar albino rats were randomly divided into three groups, and administered benidipine hydrochloride (10 ?g/kg/day) orally through a catheter for 2 h to form the study group (BIR group, n=8). The I/R procedure was performed in the rats of the IR group (n=8), and a sham group was formed to determine the normal structure of the cerebral cortex (n=8). Transient ischemia was performed by clamping the left common carotid artery for 2 h. Subsequently, reperfusion was applied for 12 h. Cerebral infarct volumes were measured and cerebral cortex tissue samples were analyzed histopathologically and biochemically by measuring malondialdehyde (MDA), total glutathione, cyclooxygenase 1 (COX-1), COX-2 and superoxide dismutase (SOD) RESULTS: The infarct area was markedly reduced in the BIR group vs. the IR group. Histopathologically, neuroprotective effects of benidipine hydrochloride were observed in the cerebral cortex tissues. The mean malondialdehyde and COX-2 levels were statistically higher in the IR group; however, in the BIR group, these levels were within the normal limits. Furthermore, the mean total glutathione, COX-1 and SOD levels were markedly lower in the IR group, and within the normal limits in the BIR group. CONCLUSION: Benidipine hydrochloride may play a certain protective role in cerebral I/R injury. This effect may be related to improvement in the antioxidant capacity of brain tissue, and the inhibition of overproduction of inflammatory cytokines.


Assuntos
Isquemia Encefálica/patologia , Encéfalo/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Nifedipino/análogos & derivados , Traumatismo por Reperfusão/patologia , Animais , Masculino , Nifedipino/farmacologia , Distribuição Aleatória , Ratos , Ratos Wistar
6.
Acta Neuropathol Commun ; 8(1): 166, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-33076989

RESUMO

Repeated exposure to mild TBI (mTBI) has been linked to an increased risk of Alzheimer's disease (AD), chronic traumatic encephalopathy (CTE) and other neurodegenerative diseases. Some pathological features typically observed in AD have been found in postmortem brains of TBI and CTE, hence treatments tested for AD have a potential to be effective against r-mTBI outcomes. Neuroinflammation may present a possible answer due to its central role both in acute brain injury and in chronic degenerative-like disorders. Our previous studies have shown that drug nilvadipine, acting as an inhibitor of spleen tyrosine kinase (SYK), is effective at reducing inflammation, tau hyperphosphorylation and amyloid production in AD mouse models. To demonstrate the effect of nilvadipine in the absence of age-related variables, we introduced the same treatment to young r-mTBI mice. We further investigate therapeutic mechanisms of nilvadipine using its racemic properties. Both enantiomers, (+)-nilvadipine and (-)-nilvadipine, can lower SYK activity, whereas (+)-nilvadipine is also a potent L-type calcium channel blocker (CCB) and shown to be anti-hypertensive. All r-mTBI mice exhibited increased neuroinflammation and impaired cognitive performance and motor functions. Treatment with racemic nilvadipine mitigated the TBI-induced inflammatory response and significantly improved spatial memory, whereas (-)-enantiomer decreased microgliosis and improved spatial memory but failed to reduce the astroglial response to as much as the racemate. These results suggest the therapeutic potential of SYK inhibition that is enhanced when combined with the CCB effect, which indicate a therapeutic advantage of multi-action drugs for r-mTBI.


Assuntos
Concussão Encefálica/fisiopatologia , Bloqueadores dos Canais de Cálcio/farmacologia , Nifedipino/análogos & derivados , Aprendizagem Espacial/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos , Quinase Syk/antagonistas & inibidores , Animais , Antígenos CD/efeitos dos fármacos , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/efeitos dos fármacos , Antígenos de Diferenciação Mielomonocítica/metabolismo , Concussão Encefálica/metabolismo , Concussão Encefálica/psicologia , Proteínas de Ligação ao Cálcio/efeitos dos fármacos , Proteínas de Ligação ao Cálcio/metabolismo , Proteína Glial Fibrilar Ácida/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Inflamação/metabolismo , Camundongos , Proteínas dos Microfilamentos/efeitos dos fármacos , Proteínas dos Microfilamentos/metabolismo , Nifedipino/farmacologia , Fosforilação , Teste de Desempenho do Rota-Rod , Aprendizagem Espacial/fisiologia , Memória Espacial/fisiologia , Quinase Syk/efeitos dos fármacos , Quinase Syk/metabolismo
7.
Intern Med ; 59(11): 1401-1405, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32475907

RESUMO

A 69-year-old man was referred to our department with acute hepatitis. He had been newly treated with benidipine hydrochloride for two months. His blood test results were as follows: aspartate aminotransferase, 1,614 IU/L; alanine aminotransferase, 1,091 IU/L and anti-smooth muscle antibody, ×80. Needle liver biopsy specimen showed interface hepatitis with mainly lymphocytic infiltration and bridging fibrosis in the periportal area. Immunohistochemistry revealed lymphocytic infiltration positive for IgG4. We diagnosed him with IgG4-related AIH with an etiology that was suspected of being drug-induced. Oral prednisolone was started and then tapered after achieving biochemical remission. Hepatitis recurred after the cessation of steroids; however, remission was achieved with ursodeoxycholic acid.


Assuntos
Hepatite Autoimune/tratamento farmacológico , Hepatite Autoimune/etiologia , Hepatite Crônica/tratamento farmacológico , Imunoglobulina G/sangue , Nifedipino/efeitos adversos , Nifedipino/uso terapêutico , Prednisolona/uso terapêutico , Idoso , Anti-Inflamatórios/uso terapêutico , Colagogos e Coleréticos/uso terapêutico , Hepatite Autoimune/diagnóstico , Humanos , Japão , Masculino , Nifedipino/análogos & derivados , Resultado do Tratamento , Ácido Ursodesoxicólico/uso terapêutico
8.
J Gerontol A Biol Sci Med Sci ; 75(5): 987-994, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-31613323

RESUMO

BACKGROUND: Use of anticholinergic medication is associated with an increased risk of cognitive impairment and/or dementia. Despite this, the impact of continuing medication with anticholinergic properties in those diagnosed with Alzheimer's Disease (AD) is not clear. METHODS: Analysis of data from NILVAD, an 18-month randomized controlled trial of Nilvadipine in AD. Effects of ongoing Anticholinergic Cognitive Burden (ACB) on cognition (ADAS-Cog: Alzheimer's Disease Cog Subsection) and dementia severity (CDR-sb: Clinical Dementia Rating - Sum of Boxes/DAD: Disability Assessment for Dementia) over 18 months was evaluated adjusting for important clinical covariates. RESULTS: Just over one-quarter (27.90%, n = 142/510) of patients with mild to moderate AD were prescribed a potential/definite anticholinergic. While ACB score was not associated with greater progression on the ADAS-Cog/CDR-sb over time, a higher total ACB predicted greater dementia severity on the DAD, which persisted after robust covariate adjustment (ß Coef: -1.53, 95% CI: -2.83 to -0.23, p = .021). There was a significant interaction between APOE ε4 status and ACB score, with carriers experiencing greater progression on both the CDR-Sb (ß Coef: 0.36, 95% CI: 0.05-0.67, p = .021) and DAD (ß Coef: -3.84, 95% CI: -7.65 to 0.03, p = .049). CONCLUSIONS: Ongoing use of anticholinergic medication was associated with greater dementia progression on the DAD, but not the CDR-sb. APOE ε 4 carriers may be particularly vulnerable to the effect of ongoing anticholinergic medication on dementia severity, with significant APOE ε 4 x ACB score interactions demonstrated on both the DAD and CDR-sb.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Antagonistas Colinérgicos/efeitos adversos , Disfunção Cognitiva/induzido quimicamente , Nifedipino/análogos & derivados , Idoso , Apolipoproteína E4 , Antagonistas Colinérgicos/administração & dosagem , Avaliação da Deficiência , Progressão da Doença , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Nifedipino/administração & dosagem , Nifedipino/efeitos adversos , Fatores de Risco , Índice de Gravidade de Doença
9.
Chin J Nat Med ; 17(9): 690-697, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31526504

RESUMO

Herein, the purpose of this study is to evaluate the effects of kaempferol on bioavailability and pharmacokinetics of nifedipine and its metabolite dehydronifedipine in rats. The experimental design is based on with or without kaempferol in the oral and intravenous administration of nifedipine in rats. Moreover, the pharmacokinetic parameters including nifedipine and dehydronifedipine were evaluated in rats.The in vitro studies ofkaempferol were investigated on P-glycoprotein (P-gp) and cytochrome P450 (CYP) 3A4 activity. Kaempferol reduced a 50% inhibitory concentration (IC50) of 8.6 µmol·L-1 on CYP3A4 enzyme activity. Moreover, kaempferol clearly improved the cell internalization of rhodamine-123 in MCF-7/ADR cells overexpressing P-gp. Depending on increased concentrations of kaempferol, the areas under the plasma concentration-time curve (AUC0-∞) and the peak concentration (Cmax) of nifedipine were increased after oral and intravenous administration. Moreover, the absolute bioavailability (AB) and relative bioavailability (RB) of nifedipine in the presence of kaempferol was significantly higher than those of the control group after oral and intravenous administration. Improvement of bioavailability of nifedipine by kaempferol may be mainly because of the inhibition of the P-gp-mediated efflux transporter in the small intestine and CYP3A4-mediated metabolism in the small intestine or liver, or both.


Assuntos
Inibidores do Citocromo P-450 CYP3A/farmacologia , Quempferóis/farmacologia , Nifedipino/farmacocinética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Disponibilidade Biológica , Linhagem Celular , Citocromo P-450 CYP3A/metabolismo , Relação Dose-Resposta a Droga , Vias de Administração de Medicamentos , Humanos , Concentração Inibidora 50 , Masculino , Nifedipino/administração & dosagem , Nifedipino/análogos & derivados , Ratos Sprague-Dawley , Rodamina 123/metabolismo
10.
Hypertension ; 74(5): 1172-1180, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31542965

RESUMO

Blood pressure variability (BPV) has been shown to have predictive value over blood pressure (BP) levels alone in stroke patients. We assessed whether BPV predicts cognitive and functional decline in Alzheimer disease, using data from a randomized trial (NILVAD [A European Multicentre Double-blind Placebo-controlled Phase III Trial of Nilvadipine in Mild to Moderate Alzheimer's Disease]). Patients with mild-to-moderate Alzheimer disease were included if they had ≥3 office BP measurements available to determine visit-to-visit BPV. Day-to-day BPV was assessed using home BP measurements in a subsample. The variation independent of mean was used to calculate BPV. Outcomes were change in Alzheimer's Disease Assessment Scale-cognitive subscale-12 and Disability Assessment for Dementia after 1 and 1.5 years. A total of 460 patients aged 72.1 (SD=8.1) years, with mean BP of 134.0/75.1 (10.9/6.3) mm Hg were included. After 1 year, patients in the highest quartile of BPV had deteriorated more on Alzheimer's Disease Assessment Scale-cognitive subscale compared with patients in the lowest quartile (systolic: ß, 2.24 [95% CI, 0.11-4.38], P=0.040; diastolic: ß, 2.54 [95% CI, 0.33-4.75] P=0.024). This association was still present after 1.5 years (systolic: ß, 2.86 [95% CI, 0.35-5.36], P=0.026; diastolic: ß, 3.30 [95% CI, 0.67-5.93], P=0.014). There was no effect of visit-to-visit BPV on Disability Assessment for Dementia. Day-to-day BPV was available for 46 patients. Significant associations were observed between day-to-day BPV and deterioration on Alzheimer's Disease Assessment Scale-cognitive subscale (systolic: P=0.036) and Disability Assessment for Dementia (systolic: P=0.020; diastolic: P=0.007) after 1 year, but not after 1.5 years. All associations were adjusted for potential confounders, including intervention group. In conclusion, this post hoc analysis indicates that higher visit-to-visit and day-to-day BPV might be associated with progression of Alzheimer disease. Targeting BPV may be a future target to slow decline in patients with Alzheimer disease. Clinical Trial Registration URL: https://www.clinicaltrials.gov. Unique identifier: NCT02017340.


Assuntos
Doença de Alzheimer/fisiopatologia , Anti-Hipertensivos/uso terapêutico , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Nifedipino/análogos & derivados , Idoso , Doença de Alzheimer/epidemiologia , Determinação da Pressão Arterial/métodos , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/fisiopatologia , Intervalos de Confiança , Progressão da Doença , Método Duplo-Cego , Feminino , Humanos , Hipertensão/epidemiologia , Modelos Lineares , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Análise Multivariada , Nifedipino/uso terapêutico , Prognóstico , Medição de Risco , Índice de Gravidade de Doença
11.
Cell Res ; 29(9): 739-753, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31444469

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS), an emerging tick-borne infectious disease caused by a novel phlebovirus (SFTS virus, SFTSV), was listed among the top 10 priority infectious diseases by the World Health Organization due to its high fatality of 12%-50% and possibility of pandemic transmission. Currently, effective anti-SFTSV intervention remains unavailable. Here, by screening a library of FDA-approved drugs, we found that benidipine hydrochloride, a calcium channel blocker (CCB), inhibited SFTSV replication in vitro. Benidipine hydrochloride was revealed to inhibit virus infection through impairing virus internalization and genome replication. Further experiments showed that a broad panel of CCBs, including nifedipine, inhibited SFTSV infection. The anti-SFTSV effect of these two CCBs was further analyzed in a humanized mouse model in which CCB treatment resulted in reduced viral load and decreased fatality rate. Importantly, by performing a retrospective clinical investigation on a large cohort of 2087 SFTS patients, we revealed that nifedipine administration enhanced virus clearance, improved clinical recovery, and remarkably reduced the case fatality rate by >5-fold. These findings are highly valuable for developing potential host-oriented therapeutics for SFTS and other lethal acute viral infections known to be inhibited by CCBs in vitro.


Assuntos
Phlebovirus/fisiologia , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Canais de Cálcio Tipo L/química , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Linhagem Celular , Chlorocebus aethiops , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Nifedipino/análogos & derivados , Nifedipino/farmacologia , Nifedipino/uso terapêutico , Febre por Flebótomos/tratamento farmacológico , Febre por Flebótomos/patologia , Febre por Flebótomos/virologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Estudos Retrospectivos , Células Vero , Carga Viral , Replicação Viral/efeitos dos fármacos
12.
Hypertension ; 74(2): 413-420, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31203725

RESUMO

Cerebrovascular changes, including reduced cerebral blood flow (CBF), occur early in the development of Alzheimer disease and may accelerate disease progression. This randomized, double-blind, placebo-controlled study investigated how 6 months of treatment with the calcium antagonist nilvadipine would affect CBF in patients with mild-to-moderate Alzheimer disease. CBF was measured with magnetic resonance arterial spin labeling in whole-brain gray matter and in a priori defined regions of interest including the hippocampus. Fifty-eight patients were randomly assigned (29 in each group), of whom 22 in both groups had no magnetic resonance exclusion criteria and were medication compliant over 6 months. Mean age was 72.8±6.2 years, mean mini-mental state examination was 20.4±3.4. Nilvadipine treatment lowered systolic blood pressure (Δ=-11.5 [95% CI, -19.7 to -3.2] mm Hg; P<0.01), while whole-brain gray-matter CBF remained stable (Δ=5.4 [95% CI, -6.4 to 17.2] mL/100 g per minute; P=0.36). CBF in the hippocampus increased (left: Δ=24.4 [95% CI, 4.3-44.5] mL/100 g per minute; P=0.02; right: Δ=20.1 [95% CI, -0.6 to 40.8] mL/100 g per minute; P=0.06). There was no significant change in CBF in the posterior cingulate cortex (Δ=5.2 [95% CI, -16.5 to 27.0] mL/100 g per minute; P=0.63) or other regions of interest. In conclusion, nilvadipine reduced blood pressure and increased CBF in the hippocampus, whereas other regions showed stable or small nonsignificant increases in CBF. These findings not only indicate preserved cerebral autoregulation in Alzheimer disease but also point toward beneficial cerebrovascular effects of antihypertensive treatment. Clinical Trial Registration- URL: http://www.clinicaltrials.gov . Unique identifier: NCT02017340.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/tratamento farmacológico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Circulação Cerebrovascular/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Nifedipino/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/epidemiologia , Método Duplo-Cego , Feminino , Humanos , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Países Baixos , Nifedipino/uso terapêutico , Prognóstico , Valores de Referência , Medição de Risco , Índice de Gravidade de Doença , Resultado do Tratamento , Ultrassonografia Doppler/métodos
13.
J Am Heart Assoc ; 8(10): e011938, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31088188

RESUMO

Background Hypertension is common among patients with Alzheimer disease. Because this group has been excluded from hypertension trials, evidence regarding safety of treatment is lacking. This secondary analysis of a randomized controlled trial assessed whether antihypertensive treatment increases the prevalence of orthostatic hypotension (OH) in patients with Alzheimer disease. Methods and Results Four hundred seventy-seven patients with mild-to-moderate Alzheimer disease were randomized to the calcium-channel blocker nilvadipine 8 mg/day or placebo for 78 weeks. Presence of OH (blood pressure drop ≥20/≥10 mm Hg after 1 minute of standing) and OH-related adverse events (dizziness, syncope, falls, and fractures) was determined at 7 follow-up visits. Mean age of the study population was 72.2±8.2 years and mean Mini-Mental State Examination score was 20.4±3.8. Baseline blood pressure was 137.8±14.0/77.0±8.6 mm Hg. Grade I hypertension was present in 53.4% (n=255). After 13 weeks, blood pressure had fallen by -7.8/-3.9 mm Hg for nilvadipine and by -0.4/-0.8 mm Hg for placebo ( P<0.001). Across the 78-week intervention period, there was no difference between groups in the proportion of patients with OH at a study visit (odds ratio [95% CI]=1.1 [0.8-1.5], P=0.62), nor in the proportion of visits where a patient met criteria for OH, corrected for number of visits (7.7±13.8% versus 7.3±11.6%). OH-related adverse events were not more often reported in the intervention group compared with placebo. Results were similar for those with baseline hypertension. Conclusions This study suggests that initiation of a low dose of antihypertensive treatment does not significantly increase the risk of OH in patients with mild-to-moderate Alzheimer disease. Clinical Trial Registration URL: https://www.clinicaltrials.gov . Unique identifier: NCT02017340.


Assuntos
Doença de Alzheimer/epidemiologia , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/uso terapêutico , Hipertensão/tratamento farmacológico , Hipotensão Ortostática/epidemiologia , Nifedipino/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/fisiopatologia , Anti-Hipertensivos/efeitos adversos , Bloqueadores dos Canais de Cálcio/efeitos adversos , Método Duplo-Cego , Europa (Continente)/epidemiologia , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Hipotensão Ortostática/diagnóstico , Hipotensão Ortostática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Nifedipino/efeitos adversos , Nifedipino/uso terapêutico , Postura , Prevalência , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
14.
J Control Release ; 298: 68-82, 2019 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-30731151

RESUMO

Liquid-liquid phase separation (LLPS) occurs following amorphous solid dispersion (ASD) dissolution when the drug concentration exceeds the "amorphous solubility", and is emerging as an important characteristic of formulations that may enhance the oral bioavailability of poorly soluble drugs. The purpose of this research was to identify criteria that impact the rate and extent of drug release and hence the occurrence or not of LLPS upon ASD dissolution. Specifically, the effect of drug log P, phase behavior of the hydrated but undissolved ASD matrix and the relative dissolution rates of drug and polymer were studied as a function of drug loading, using nilvadipine (Nil) (ClogP = 3.04) and cilnidipine (Cil) (ClogP = 5.54) as model drugs. The model polymer was poly (vinylpyrrolidone-co-vinyl acetate) (PVPVA). Nil-PVPVA and Cil-PVPVA ASDs with different drug loadings were prepared. Surface area normalized dissolution rates of both the drug and the polymer from ASD tablets were studied. At a similar and relatively low drug loading (<20% w/w drug), dissolution of both Nil-PVPVA and Cil-PVPVA ASDs was found to switch from rapid, congruent (i.e., simultaneous) release of drug and polymer to incongruent release with slow release of drug. Only ASDs showing congruent release underwent LLPS, with the formation of amorphous drug-rich aggregates (~300nm). Scanning electron microscopy (SEM) and micro-computed tomography (micro-CT) showed the presence of characteristic "pits" on the surface of partially dissolved, incongruently releasing ASD tablets. These most likely arise due to faster polymer release in comparison to drug, whereby the drug-rich composition around these pits was confirmed by energy-dispersive X-ray (EDX) analysis and the surface drug enrichment on the compacts was confirmed by X-ray photoelectron spectroscopy (XPS). This study demonstrates two important findings, firstly, a link between congruent release of drug and polymer and the occurrence of LLPS and secondly, the switch between congruent and incongruent release of drug and polymer is a result of competitive kinetics between phase separation and the release rate of ASD components with minimal influence from drug hydrophobicity for two structural analogues.


Assuntos
Di-Hidropiridinas/administração & dosagem , Nifedipino/análogos & derivados , Polímeros/química , Pirrolidinas/química , Compostos de Vinila/química , Química Farmacêutica , Di-Hidropiridinas/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Nifedipino/administração & dosagem , Nifedipino/química , Solubilidade , Microtomografia por Raio-X
15.
J Biomol Struct Dyn ; 37(12): 3162-3167, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30238824

RESUMO

In this study, a nanoemulsion containing mebudipine [composed of ethyl oleate (oil phase), Tween 80 (T80), Span 80 (S80) (surfactants), polyethylene glycol 400, ethanol (cosurfactants), and deionized water] was prepared with the aim of improving its bioavailability for an effective antihypertensive therapy. Particle size of the formulation was measured by dynamic light scattering. Then, artificial neural networks were used in identifying factors that influence the particle size of the nanoemulsion. Three variables, namely, amount of surfactant system (T80 + S80), amount of polyethylene glycol, and amount of ethanol as cosurfactants, were considered as input values and the particle size was used as output. The developed model showed that all the three inputs had some degrees of effect on particles size: increasing the value of each input decreased the size. Furthermore, amount of surfactant was found to be the dominant factor in controlling the final particle size of nanoemulsion. Communicated by Ramaswamy H. Sarma.


Assuntos
Emulsões/química , Nanopartículas/química , Nifedipino/análogos & derivados , Etanol/química , Hexoses/química , Redes Neurais de Computação , Nifedipino/química , Ácidos Oleicos/química , Tamanho da Partícula , Polietilenoglicóis/química , Polissorbatos/química , Tensoativos/química , Água/química
16.
Pharmacology ; 102(5-6): 287-299, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30253416

RESUMO

BACKGROUND/AIMS: We have reported that nitrosonifedipine (NO-NIF), a photodegradation product of nifedipine, has strong antioxidant and endothelial protective effects, and can suppress several cardiovascular diseases in animal models. The objective of the present study was to investigate the effects of NO-NIF on aortic aneurysm formation. METHODS: The mice were infused with ß-aminopropionitrile for 2 weeks and angiotensin II for 6 weeks to induce aortic aneurysm formation. The oxidative stress was measured by dihydroethidium staining and nitrotyrosine staining. The expressions of inflammation-related genes were assessed by quantitative real-time PCR and immunohistochemical staining. To clarify the mechanisms of how NO-NIF suppresses vascular cell adhesion molecule (VCAM)-1, endothelial cells were used in in vitro system. RESULTS: NO-NIF suppressed pharmacologically induced the aortic aneurysm formation and aortic expansion without blood pressure changes. NO-NIF suppressed elastin degradation and matrix metalloproteinase-2 mRNA expression. NO-NIF suppressed the reactive oxygen species-cyclophilin A positive feedback loop. Upregulated mRNA expressions of inflammation-related genes and endothelial VCAM-1 were suppressed by NO-NIF co-treatment in aortae. CONCLUSION: NO-NIF has the potential to be a new, nifedipine-derived therapeutic drug for suppressing aortic aneurysm formation by directly improving aortic structure with its strong ability to reduce oxidative stress and inflammation.


Assuntos
Aneurisma Aórtico/tratamento farmacológico , Nifedipino/análogos & derivados , Compostos Nitrosos/farmacologia , Aminopropionitrilo/administração & dosagem , Angiotensina II/administração & dosagem , Animais , Antígenos de Diferenciação/metabolismo , Antioxidantes/farmacologia , Aneurisma Aórtico/induzido quimicamente , Aneurisma Aórtico/metabolismo , Quimiocina CCL2/metabolismo , Ciclofilinas/metabolismo , Modelos Animais de Doenças , Elastina/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , Nifedipino/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fotólise , Espécies Reativas de Oxigênio/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
17.
PLoS Med ; 15(9): e1002660, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30248105

RESUMO

BACKGROUND: This study reports the findings of the first large-scale Phase III investigator-driven clinical trial to slow the rate of cognitive decline in Alzheimer disease with a dihydropyridine (DHP) calcium channel blocker, nilvadipine. Nilvadipine, licensed to treat hypertension, reduces amyloid production, increases regional cerebral blood flow, and has demonstrated anti-inflammatory and anti-tau activity in preclinical studies, properties that could have disease-modifying effects for Alzheimer disease. We aimed to determine if nilvadipine was effective in slowing cognitive decline in subjects with mild to moderate Alzheimer disease. METHODS AND FINDINGS: NILVAD was an 18-month, randomised, placebo-controlled, double-blind trial that randomised participants between 15 May 2013 and 13 April 2015. The study was conducted at 23 academic centres in nine European countries. Of 577 participants screened, 511 were eligible and were randomised (258 to placebo, 253 to nilvadipine). Participants took a trial treatment capsule once a day after breakfast for 78 weeks. Participants were aged >50 years, meeting National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's disease Criteria (NINCDS-ADRDA) for diagnosis of probable Alzheimer disease, with a Standardised Mini-Mental State Examination (SMMSE) score of ≥12 and <27. Participants were randomly assigned to 8 mg sustained-release nilvadipine or matched placebo. The a priori defined primary outcome was progression on the Alzheimer's Disease Assessment Scale Cognitive Subscale-12 (ADAS-Cog 12) in the modified intention-to-treat (mITT) population (n = 498), with the Clinical Dementia Rating Scale sum of boxes (CDR-sb) as a gated co-primary outcome, eligible to be promoted to primary end point conditional on a significant effect on the ADAS-Cog 12. The analysis set had a mean age of 73 years and was 62% female. Baseline demographic and Alzheimer disease-specific characteristics were similar between treatment groups, with reported mean of 1.7 years since diagnosis and mean SMMSE of 20.4. The prespecified primary analyses failed to show any treatment benefit for nilvadipine on the co-primary outcome (p = 0.465). Decline from baseline in ADAS-Cog 12 on placebo was 0.79 (95% CI, -0.07-1.64) at 13 weeks, 6.41 (5.33-7.49) at 52 weeks, and 9.63 (8.33-10.93) at 78 weeks and on nilvadipine was 0.88 (0.02-1.74) at 13 weeks, 5.75 (4.66-6.85) at 52 weeks, and 9.41 (8.09-10.73) at 78 weeks. Exploratory analyses of the planned secondary outcomes showed no substantial effects, including on the CDR-sb or the Disability Assessment for Dementia. Nilvadipine appeared to be safe and well tolerated. Mortality was similar between groups (3 on nilvadipine, 4 on placebo); higher counts of adverse events (AEs) on nilvadipine (1,129 versus 1,030), and serious adverse events (SAEs; 146 versus 101), were observed. There were 14 withdrawals because of AEs. Major limitations of this study were that subjects had established dementia and the likelihood that non-Alzheimer subjects were included because of the lack of biomarker confirmation of the presence of brain amyloid. CONCLUSIONS: The results do not suggest benefit of nilvadipine as a treatment in a population spanning mild to moderate Alzheimer disease. TRIAL REGISTRATION: Clinicaltrials.gov NCT02017340, EudraCT number 2012-002764-27.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Nifedipino/análogos & derivados , Nootrópicos/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/psicologia , Progressão da Doença , Método Duplo-Cego , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nifedipino/uso terapêutico , Resultado do Tratamento
18.
High Blood Press Cardiovasc Prev ; 25(1): 25-34, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29197935

RESUMO

Essential hypertension is a complex clinical condition, characterized by multiple and concomitant abnormal activation of different regulatory and contra-regulatory pathophysiological mechanisms, leading to sustained increase of blood pressure (BP) levels. Asymptomatic rise of BP may, indeed, promote development and progression of hypertension-related organ damage, which in turn, increases the risk of major cardiovascular and cerebrovascular events. A progressive and independent relationship has been demonstrated between high BP levels and increased cardiovascular risk, even in the high-to-normal range. Conversely, evidence from randomized controlled clinical trials have independently shown that lowering BP to the recommended targets reduces individual cardiovascular risk, thus improving event-free survival and reducing the incidence of hypertension-related cardiovascular events. Despite these benefits, overall rates of BP control remain poor, worldwide. Currently available guidelines support a substantial equivalence amongst various antihypertensive drug classes. However, several studies have also reported clinically relevant differences among antihypertensive drugs, in terms of both BP lowering efficacy and tolerability/safety profile. These differences should be taken into account not only when adopting first-line antihypertensive therapy, but also when titrating or modulating combination therapies, with the aim of achieving effective and sustained BP control. This review will briefly describe evidence supporting the use of dihydropyridinic calcium channel blockers for the clinical management of hypertension, with a particular focus on barnidipine. Indeed, this drug has been demonstrated to be effective, safe and well tolerated in lowering BP levels and in reducing hypertension-related organ damage, thus showing a potential key role for improving the clinical management of hypertension.


Assuntos
Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/uso terapêutico , Di-Hidropiridinas/uso terapêutico , Hipertensão Essencial/tratamento farmacológico , Adesão à Medicação , Nifedipino/análogos & derivados , Vasodilatadores/uso terapêutico , Anti-Hipertensivos/efeitos adversos , Bloqueadores dos Canais de Cálcio/efeitos adversos , Di-Hidropiridinas/efeitos adversos , Hipertensão Essencial/diagnóstico , Hipertensão Essencial/fisiopatologia , Humanos , Nifedipino/efeitos adversos , Nifedipino/uso terapêutico , Fatores de Risco , Resultado do Tratamento , Vasodilatadores/efeitos adversos
19.
Chem Pharm Bull (Tokyo) ; 65(12): 1175-1178, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29199222

RESUMO

The powder properties of two 1,4-dihydropyridine type compounds, manidipine dihydrochloride (Man) and benidipine hydrochloride (Ben), which possess similar physicochemical properties, were compared through thermal and mechanical analyses. Man and Ben were compressed with lactose monohydrate (Lac) and magnesium stearate (Mgst) at different compression forces. As an index, we focused on the onset temperatures of Lac dehydration during thermal analysis and plotted them against compression forces to evaluate the differences in powder properties between Man and Ben. To discuss in detail, the Lac ratio was selected as a formulation factor and compression speed as a process factor, which would be influenced to the onset temperature or its profile. It could be represented that Man was more adherent than Ben through thermal analysis by changing these critical factors, which were consistent with the results obtained through mechanical analysis.


Assuntos
Di-Hidropiridinas/química , Nifedipino/análogos & derivados , Varredura Diferencial de Calorimetria , Força Compressiva , Lactose/química , Nifedipino/química , Nitrobenzenos , Piperazinas , Ácidos Esteáricos/química , Comprimidos/química , Temperatura
20.
Int J Mol Sci ; 18(12)2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29244747

RESUMO

Retinopathy leads to irreparable vision loss via capillary closure and areas of nonperfusion. However, the current instillation systems do not allow a sufficient amount of drug required to treat retinopathy to reach the posterior segment (retina); therefore, a new formulation targeting the posterior segment is expected as therapy for retinopathy. We prepared ophthalmic formulations containing nilvadipine nanoparticles (NILnano), and demonstrated whether the instillation of NILnano can prevent retinal dysfunction in rats injected with excessive streptozotocin (STZ rats) in this study. NILnano (mean particle size, 77 nm) was prepared by wet bead mill treatment, with the inclusion of various additives (2-hydroxypropyl-ß-cyclodextrin, benzalkonium chloride, d-mannitol, and methylcellulose). Retinal dysfunction was observable two weeks after rats received intraperitoneal injections of streptozotocin (100 mg/kg × 2, consecutive days, STZ rat). Changes in retinal function were evaluated by electroretinogram (ERG) and immunological methods. The retinal thickness, measured as the distance between the ganglion cell layer and the distal border of the outer nuclear layer, increased two weeks after the injection of streptozotocin, resulting in decreases in the levels of a-waves, b-waves, and oscillatory potential amplitudes in ERG of rats. The instillation of NILnano allowed the topical supplement of nilvadipine into the retina, and repeated instillation of NILnano (2 times/day) attenuated the retinal disorders led by the excessive streptozotocin. In conclusion, we found that retinal dysfunction in rats injected with streptozotocin can be prevented by the NILnano instillation. These results are useful in further studies aimed at the therapeutic treatment of retinopathy.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Retinopatia Diabética/tratamento farmacológico , Nifedipino/análogos & derivados , Estreptozocina/efeitos adversos , Animais , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/patologia , Retinopatia Diabética/induzido quimicamente , Retinopatia Diabética/fisiopatologia , Eletrorretinografia , Humanos , Nanopartículas/administração & dosagem , Nanopartículas/química , Nifedipino/administração & dosagem , Nifedipino/química , Ratos , Retina/efeitos dos fármacos , Retina/fisiopatologia
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