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1.
Oncol Res ; 28(6): 681-682, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33731248

RESUMO

Colon cancer (CC) is the third most common cancer worldwide. Emodin is an anthraquinone-active substance that has the ability to affect tumor progression. Our study aims to explore the effects and the relevant mechanism of emodin on the invasion and migration of CC in vitro and in vivo. In our study, we found that emodin inhibited the invasion and migration abilities of RKO cells and decreased the expression of matrix metalloproteinase-7 (MMP-7), MMP-9, and vascular endothelial growth factor (VEGF) in a dose-dependent manner. Further research suggested that emodin inhibited EMT by increasing the mRNA level of E-cadherin and decreasing the expression of N-cadherin, Snail, and -catenin. Emodin also significantly inhibited the activation of the Wnt/-catenin signaling pathway by downregulating the expression of related downstream target genes, including TCF4, cyclin D1, and c-Myc. A Wnt/-catenin signaling pathway agonist abolished the effect of emodin on EMT and cell mobility, suggesting that emodin exerted its regulating role through the Wnt/-catenin pathway. The CC xenograft model was established to study the antitumor efficiency of emodin in vivo. The in vivo study further demonstrated that emodin (40 mg/kg) suppressed tumor growth by inhibiting EMT via the Wnt/-catenin signaling pathway in vivo. Taken together, we suggest that emodin inhibits the invasion and migration of CC cells in vitro and in vivo by blocking EMT, which is related with the inhibition of the Wnt/-catenin signaling pathway.

2.
Nano Lett ; 20(12): 8903-8911, 2020 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-33232167

RESUMO

While protein coronas (PCs) are an important barrier in the clinical application of nanomedicines, the specific effects of PCs on nanoparticles (NPs) in vivo are unclear. Herein, we demonstrated that PCs from clinical sources greatly influenced the active targeting capacities of transferrin-modified NPs (Tf-NPs). Compared to PCs from healthy volunteers, PCs from the plasma of patients with nonsmall cell lung cancer (NSCLC) decreased the A549 uptake of Tf-NPs to a greater degree. The PC proteome revealed that this difference may be mediated by certain proteins in plasma. To attenuate the negative influence of PCs from patients, precoating Tf-NPs with PCs derived from healthy mice significantly enhanced active targeting capacities. Paclitaxel-loaded Tf-NPs with PCs derived from healthy mice showed the strongest antitumor effects in mice with NSCLC. This work illustrates the influence of PCs of ligand-modified NPs in clinical practice and proposes the use of corona-enabled active targeting for precision nanomedicine.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Nanopartículas , Preparações Farmacêuticas , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos
3.
R Soc Open Sci ; 7(2): 191666, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32257329

RESUMO

ET-26-HCl, a novel anaesthetic agent with promising pharmacological properties, lacks extensive studies on pharmacokinetics and disposition in vitro and in vivo. In this study, we investigated the metabolic stability, metabolite production and plasma protein binding (PPB) of ET-26-HCl along with its tissue distribution, excretion and pharmacokinetics in animals after intravenous administration. Ultra-high performance liquid chromatography-tandem quadrupole time-of-flight mass spectrometry identified a total of eight new metabolites after ET-26-HCl biotransformation in liver microsomes from different species. A hypothetical cytochrome P450-metabolic pathway including dehydrogenation, hydroxylation and demethylation was proposed. The PPB rate was highest in mouse and lowest in human. After intravenous administration, ET-26-HCl distributed rapidly to all tissues in rats and beagle dogs, with the highest concentrations in fat and liver. High concentrations of ET-26-acid, a major hydroxylation metabolite of ET-26-HCl, were found in liver, plasma and kidney. Almost complete clearance of ET-26-HCl from plasma occurred within 4 h after administration. Only a small fraction of the parent compound and its acid form were excreted via the urine and faeces. Taken together, the results added to a better understanding of the metabolic and pharmacokinetic properties of ET-26-HCl, which may contribute to the further development of this drug.

4.
Pharm Res ; 36(12): 171, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31654287

RESUMO

PURPOSE: Physiologically-based pharmacokinetic (PBPK) modeling offers a unique modality to predict age-specific pharmacokinetics. The objective of this study was to assess the ability of PBPK model to predict plasma exposure of oxycodone, a widely used opioid for pain management, in adults and children. METHODS: A full PBPK model of oxycodone following intravenous and oral administration was developed using a 'bottom-up' and 'top-down' combined strategy. The model was then extrapolated to pediatrics through a reasonable scaling method. The adult and pediatric model was evaluated using data from 17 clinical PK studies by testing predicted/observed goodness of fit. The mean fold error for PK parameters was calculated. Finally, we used the validated PBPK model to visualize adult-children dose conversion for oxycodone. RESULTS: The developed PBPK model successfully predicted the oxycodone disposition in adults, wherein the predicted versus observed AUC, Cmax, and tmax were within 0.90 to 1.20-fold difference. After scaling anatomy/physiology, protein binding, and clearance, the model showed satisfactory prediction performance for pediatric populations as predicted AUC were within the 1.50-fold range of the observed values. According to the application of PBPK model, we found that different intravenous doses should be given in children of different ages compared to a standard 0.1 mg/kg in adults, while a progressive increasing dose with age growth following oral administration is recommended for children. CONCLUSIONS: The current example provides the opportunity for using the PBPK model to guide dose adjustment of oxycodone in the design of future pediatric clinical studies.


Assuntos
Analgésicos Opioides/farmacocinética , Oxicodona/farmacocinética , Administração Intravenosa , Administração Oral , Adolescente , Adulto , Analgésicos Opioides/administração & dosagem , Criança , Pré-Escolar , Simulação por Computador , Relação Dose-Resposta a Droga , Humanos , Lactente , Recém-Nascido , Taxa de Depuração Metabólica , Modelos Biológicos , Oxicodona/administração & dosagem , Pediatria
5.
Pak J Pharm Sci ; 32(2): 607-615, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31081773

RESUMO

Methyl poly(ethylene glycol) grafted poly (lactide-co-(glycolic acid)-alt-(glutamic acid) amphiphilic copolymers (PLG-g-mPEG) were fabricated polymeric micelles to load anticancer drug doxorubicin (DOX). Both blank and drug loaded micelles were spherical nanoparticles with the mean sizes around 50 and 100nm, respectively. The effects of formulation conditions including compositions, concentrations, temperature, feeding doses and solvents on the size and drug loading content were investigated, the storage of the drug loaded micelles was explored. The results showed that the short graft mPEG chain length was favorable for the loading of DOX. The increase of temperature was preferable for receive micelles with higher drug loading content and smaller size. The encapsulation of polymeric micelles could protect the bioactivity of DOX. In vitro drug release profiles illustrated that the drug release from polymeric micelles with long mPEG chains was much faster than from micelles with short mPEG chains. The release kinetics of drug from micelles fitted to the Ritger-Peppas equation well and the release process followed diffusion mechanism.


Assuntos
Doxorrubicina/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Micelas , Polietilenoglicóis/química , Ácido Poliglutâmico/análogos & derivados , Ácido Poliglutâmico/química , Solventes/química , Temperatura
6.
Oncol Res ; 27(2): 193-202, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29301594

RESUMO

Colon cancer (CC) is the third most common cancer worldwide. Emodin is an anthraquinone-active substance that has the ability to affect tumor progression. Our study aims to explore the effects and the relevant mechanism of emodin on the invasion and migration of CC in vitro and in vivo. In our study, we found that emodin inhibited the invasion and migration abilities of RKO cells and decreased the expression of matrix metalloproteinase-7 (MMP-7), MMP-9, and vascular endothelial growth factor (VEGF) in a dose-dependent manner. Further research suggested that emodin inhibited EMT by increasing the mRNA level of E-cadherin and decreasing the expression of N-cadherin, Snail, and ß-catenin. Emodin also significantly inhibited the activation of the Wnt/ß-catenin signaling pathway by downregulating the expression of related downstream target genes, including TCF4, cyclin D1, and c-Myc. A Wnt/ß-catenin signaling pathway agonist abolished the effect of emodin on EMT and cell mobility, suggesting that emodin exerted its regulating role through the Wnt/ß-catenin pathway. The CC xenograft model was established to study the antitumor efficiency of emodin in vivo. The in vivo study further demonstrated that emodin (40 mg/kg) suppressed tumor growth by inhibiting EMT via the Wnt/ß-catenin signaling pathway in vivo. Taken together, we suggest that emodin inhibits the invasion and migration of CC cells in vitro and in vivo by blocking EMT, which is related with the inhibition of the Wnt/ß-catenin signaling pathway.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Emodina/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Via de Sinalização Wnt/fisiologia , beta Catenina/fisiologia , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Invasividade Neoplásica , Transdução de Sinais/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/antagonistas & inibidores
7.
Chin J Nat Med ; 16(2): 143-149, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29455730

RESUMO

Ginsenoside Rh2 (Rh2) is one of the major bioactive ginsenosides in Panax ginseng. However, the oral bioavailability of Rh2 is low, with P-glycoprotein (P-gp) and CYP3A4 being reported to be the main factors. The purpose of the present study was to determine the enhancing effect of piperine on the oral bioavailability as well as bioactivity of Rh2. The inhibitory effect of piperine on P-gp and CYP3A4 was determined using a Caco-2 monolayer model and a recombinant CYP3A4 metabolic system, respectively. The pharmacokinetics of oral Rh2 (10 mg·kg-1) administered alone or in combination with piperine (10 and 20 mg·kg-1) was performed in rats. The immune boosting effect of Rh2 was assessed in rats by measuring IL-12 level after treated by Rh2 alone or co-administered with piperine. The results indicated that piperine significantly increased the permeability of Rh2 and inhibited the metabolism of Rh2. The pharmacokinetic study results showed that the AUC of Rh2 was significantly increased in combination with piperine at high dose (20 mg·kg-1) when compared to the control group, with relative bioavailability of 196.8%. The increase of Rh2 exposure led to increased serum levels of IL-12. In conclusion, piperine may be used as a bioenhancer to improve pharmacological effect of Rh2 when given orally.


Assuntos
Alcaloides/administração & dosagem , Benzodioxóis/administração & dosagem , Medicamentos de Ervas Chinesas/administração & dosagem , Ginsenosídeos/farmacocinética , Piperidinas/administração & dosagem , Alcamidas Poli-Insaturadas/administração & dosagem , Administração Oral , Animais , Disponibilidade Biológica , Células CACO-2 , Citocromo P-450 CYP3A/metabolismo , Ginsenosídeos/administração & dosagem , Humanos , Interleucina-2/metabolismo , Panax/química , Ratos , Ratos Sprague-Dawley
8.
Yao Xue Xue Bao ; 51(9): 1356-67, 2016 09.
Artigo em Chinês | MEDLINE | ID: mdl-29924509

RESUMO

Tamoxifen (TAM) is the most common nonsteroidal antiestrogen agent, which has been widely used in the prevention of recurrence of estrogen or progesterone receptor-positive breast cancer in patients. It is metabolized by cytochrome P450 oxidases to its active metabolite (4-hydroxytamoxifen, 4-OH-TAM) and endoxifen (EDF), which played a critical role in the therapy. 4-OH-TAM and EDF have 30- to 100-fold more potency than TAM in the suppression of estrogen-dependent breast cancer cell proliferation. CYP3A4 and CYP2D6, as the key drug-metabolizing enzymes in those metabolic actions, are known to have several alleles. Genetic polymorphisms of CYP2D6 and CYP3A4 will influence the plasma concentrations of active TAM metabolites and clinical outcomes for breast cancer patients treated with TAM. The genetic polymorphisms of drug transporters, involved in the disposition of active TAM metabolites, also have the potential to influence the plasma concentrations of active TAM metabolites and clinical outcome for the treatment of breast cancer. In this review, we summarized the association of the genetic polymorphisms in the metabolic enzymes and transporters involved in the metabolism and disposition of TAM with the metabolite concentration, efficacy and adverse effects of TAM, which provides a fundamental reference for further pharmacogenomic study and clinical use of TAM.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/genética , Antagonistas de Estrogênios/farmacologia , Farmacogenética , Tamoxifeno/farmacologia , Neoplasias da Mama/tratamento farmacológico , Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP3A/metabolismo , Humanos , Polimorfismo Genético , Tamoxifeno/análogos & derivados , Tamoxifeno/metabolismo
9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 46(5): 783-7, 804, 2015 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-26619557

RESUMO

OBJECTIVE: To develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of desloratadine and its metabolite 3-OH desloratadine in human plasma. METHODS: 24 healthy male volunteers received a single oral dose of 5 mg desloratadine tablets in a randomized crossover bioequivalence study with two preparations of tablets. Serial plasma samples were taken and analyzed by the LC-MS/MS method. The pharmacokinetic parameters of the two preparations were calculated and compared statistically to evaluate their bioequivalence using Winnonlin 6. 3. RESULTS: The calibration curves of desloratadine and 3-OH desloratadine were both linear over the concentration range of 0. 050-6. 0 ng/mL, with intra-batch and inter-batch relative standard deviations less than 15%. The 90% confidence intervals (CIs) of peak concentration (Cmax) area under the curve (AUC)0t and AUC0-∞ of desloratadine and 3-OH desloratadine all resided within the bioequivalence limit 80%-125%. No significant difference in peak time (Tmax) was demonstrated between the two preparations. CONCLUSION: The LC-MS/MS method can be used for simultaneous determination of desloratadine and 3-OH desloratadine in human plasma, which has been successfully applied-to a bioequivalence study.


Assuntos
Cromatografia Líquida , Loratadina/análogos & derivados , Espectrometria de Massas em Tandem , Área Sob a Curva , Estudos Cross-Over , Humanos , Loratadina/sangue , Loratadina/farmacocinética , Masculino , Comprimidos , Equivalência Terapêutica
10.
Yao Xue Xue Bao ; 50(3): 305-11, 2015 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-26118109

RESUMO

To study the transport mechanisms of drugs for transplacental treatment of fetal tachyarrhythmia, MDCKII-BCRP and MDCKII cell models was used. MDCKII-BCRP and MDCKII cell monolayer model was used to investigate the bi-direction transport of sotalol, propranolol, propafenone, procainamide and flecainide. Drug concentrations were measured by HPLC-UV or chemiluminescence. The apparent permeability coefficient (P(app)), efflux rate (R(E)) and net efflux rate (R(net)) were calculated. Drugs with R(net) greater than 1.5 were further investigated using cellular accumulation experiments with or without a BCRP inhibitor. The R(net) of sotalol, propranolol, propafenone and procainamide were less than 1.5, while R(net) of flecainide with concentrations of 20 and 5 µmol x L(-1) were 1.6 and 1.9, respectively. The results showed that the transport of flecainide on MDCKII-BCRP cell monolayer could be mediated by BCRP; and the affinity increased when the concentration of flecainide decreased. Cellular accumulation experiments further suggested that accumulation of flecainide in MDCKII-BCRP cells was significantly lower than that in MDCKII cells in a concentration-dependent manner. BCRP inhibitor quercetin (50 µmol x L(-1)) significantly increased the accumulation of flecainide in MDCKII-BCRP cells (P < 0.05). Our preliminary data showed that flecainide but not sotalol, propranolol, propafenone or procainamide can be a substrate of BCRP. Thus the effect of flecainide may be affected by the BCRP in the maternal placental trophoblast membrane layer when treating fetal tachyarrhythmia.


Assuntos
Transporte Biológico , Permeabilidade da Membrana Celular , Células Madin Darby de Rim Canino/metabolismo , Animais , Cães , Feminino , Flecainida/metabolismo , Placenta/fisiologia , Gravidez , Taquicardia/tratamento farmacológico
11.
Acta Pharm ; 65(2): 147-57, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26011931

RESUMO

Fructose-1,6-diphosphate (FDP), a glycolytic metabolite, has been reported to protect susceptible organs during hypoxia or ischemia. However, there is paucity of human data on its pharmacokinetics after being exogenously administered. In the current study, the preliminary pharmacokinetics of FDP given orally to humans was investigated, and no typical peak was observed in the serum drug-time curve. Then, the pharmacokinetic studies were performed following multiple doses of FDP in rats, and the Caco-2 monolayer model was used to study the absorption of FDP in vitro. The results suggested that plasma FDP concentration was significantly increased after oral multiple doses of 180 mg kg(-1) but not 90 mg kg(-1) of FDP, and FDP was partly depleted during the absorption, which was supposed to be consumed by the intestinal epithelium cells. Thus, we conclude that a high dose of FDP should be orally administered in order to get an effective plasma level.


Assuntos
Frutosedifosfatos/farmacocinética , Mucosa Intestinal/metabolismo , Fármacos Neuroprotetores/farmacocinética , Administração Oral , Animais , Células CACO-2 , Frutosedifosfatos/administração & dosagem , Humanos , Masculino , Fármacos Neuroprotetores/administração & dosagem , Ratos , Ratos Sprague-Dawley , Adulto Jovem
12.
PLoS One ; 10(4): e0122322, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25874882

RESUMO

Laryngeal cancer is the most frequent neoplasm in the head and neck region, with the vast majority of tumors originating from squamous cells. The survival rate of patients with laryngeal cancer has not improved substantially over the past 25 years. To acquire further knowledge regarding the molecules responsible for laryngeal cancer oncogenesis and, in turn, to improve target therapy iTRAQ and mass spectrometry analysis were utilized to detect differences in protein expression from 15 paired laryngeal cancer and adjacent non-cancerous tissue samples. Using mass spectrometry analysis, the expression levels of 100 proteins in laryngeal cancer samples were distinct from the non-tumor, non-cancerous samples. Further validation of the differentially expressed proteins S100A2, KRT16, FGB and HSPB1 were carried out using quantitative real-time RT-PCR, immunoblot and immunohistochemistry. Functional analysis of one of the highly expressed proteins, S100 calcium binding protein A2 (S100A2), was performed using RNA interference. As a consequence, attenuated S100A2 expression enhanced the ability of HEp-2 cell lines to migrate and invade in vitro. Our investigation complements the current understanding of laryngeal cancer progression. Furthermore, this study supports the concept that enhanced expression of S100A2 may be a promising strategy in developing novel cancer therapeutic drugs.


Assuntos
Biomarcadores Tumorais/biossíntese , Fatores Quimiotáticos/biossíntese , Neoplasias Laríngeas/genética , Proteômica , Proteínas S100/biossíntese , Idoso , Biomarcadores Tumorais/genética , Fatores Quimiotáticos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Proteínas S100/genética , Análise Serial de Tecidos
13.
Yao Xue Xue Bao ; 49(2): 252-5, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-24761618

RESUMO

To investigate the influence of the difference enhancers on the transport mechanism of chlorogenic acid (CGA) across Caco-2 cells model, a RP-HPLC method was adopted to detect the concentrations of CGA. At the concentrations of 20 to 80 microg x mL(-1), the difference of absorption rate constants (K(a)) was not statistically significant. At the concentrations of 40 and 20 microg x mL(-1), the ratios of apparent permeability coefficients (P(app)) of the apical to basolateral and the basolateral to apical were 1.14 and 1.18, respectively. With the effect of enhancers K(a) and P(app) increased, the absorption half-life (T1/2) decreased. CGA passed through the Caco-2 cell membrane mainly by passive transport. It showed that monocarboxylic acid transporter (MCT) could be involved in the across membrane transport process of CGA. Borneol had no effect on the cell membrane transport processes. The order of increasing absorption of CGA caused by the enhancers was sodium lauryl sulphate > sodium taurocholate > carbomer.


Assuntos
Resinas Acrílicas/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Ácido Clorogênico/farmacocinética , Dodecilsulfato de Sódio/farmacologia , Ácido Taurocólico/farmacologia , Absorção , Células CACO-2 , Humanos
14.
Eur J Clin Pharmacol ; 69(11): 1917-25, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23807564

RESUMO

PURPOSE: CYP3A4 is the main isoform of cytochrome P450 oxidases involved in the metabolism of approximately 60 % drugs, and its expression level is highly variable in human subjects. CYP3A4 is regulated by many transcription factors, among which the pregnane X receptor/steroid and xenobiotic receptor (PXR/SXR, NR1I2) have been identified as the most critical. Genetic polymorphisms (such as SNPs) in PXR may affect the expression level of CYP3A4. Although numerous SNPs have been identified in PXR and have appeared to affect PXR function, their impact on the expression of CYP3A4 in human subjects has not been well studied. Thus, a clinical study in healthy Chinese subjects was conducted to investigate the impact of PXR polymorphisms on repaglinide (an endogenous marker for CYP3A4 activity) pharmacokinetics used alone or in combination with a PXR inducer, flucloxacillin. METHOD: Two SNPs, -298A>G and 11193T>C, were identified as the tag SNPs to represent the overall genetic polymorphic profile of PXR. To evaluate the potential functional change of these two SNPs, 24 healthy subjects were recruited in a pharmacokinetics/pharmacodynamics study of repaglinide with or without flucloxacillin. RESULTS: The pharmacokinetic parameters including AUC and T1/2 were significantly different among the PXR genotype groups. The SNPs of -298G/G and 11193C/C were found to be associated with a lower PXR activity resulting in reduction of CYP3A4 activity in vivo. After administration of flucloxacillin, a significant drug-drug interaction was observed. The clearance of repagnilide was significantly increased by concomitant flucloxacillin in a genotype dependent manner. The subjects with SNPs of -298G/G and 11193C/C appeared to be less sensitive to flucloxacillin. CONCLUSION: Our study results demonstrated for the first time the impact of genetic polymorphisms of PXR on the PK and PD of repaglinide, and showed that subjects with genotype of -298G/G and 11193C/C in PXR has a decreased elimination rate of 3A4/2C8. Furthermore, flucloxacillin was able to induce 3A4/2C8 expression mediated by PXR in a genotype dependent manner.


Assuntos
Antibacterianos/farmacologia , Carbamatos/farmacologia , Floxacilina/farmacologia , Hipoglicemiantes/farmacologia , Piperidinas/farmacologia , Receptores de Esteroides/genética , Antibacterianos/sangue , Hidrocarboneto de Aril Hidroxilases/genética , Povo Asiático/genética , Glicemia/análise , Carbamatos/sangue , Estudos Cross-Over , Citocromo P-450 CYP2C8 , Citocromo P-450 CYP3A/genética , Interações Medicamentosas , Floxacilina/sangue , Genótipo , Voluntários Saudáveis , Humanos , Hipoglicemiantes/sangue , Piperidinas/sangue , Polimorfismo de Nucleotídeo Único , Receptor de Pregnano X , Receptores de Esteroides/metabolismo
15.
J Chromatogr Sci ; 51(9): 867-71, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23169932

RESUMO

In this study, a simple and selective high-performance liquid chromatography method was developed and validated for the determination of nifekalant hydrochloride in canine plasma. Liquid-liquid extraction was used to separate nifekalant hydrochloride from canine plasma and the mean extraction recoveries of nifekalant hydrochloride and the internal standard were 82.31 and 94.81%, respectively. The chromatographic separation was performed on a Dikma Diamonsil column with a mobile phase consisting of acetonitrile-20mM phosphate buffer (pH 6.2; 30:70, v/v) with flow rate of 1.0 mL/min. The standard curve was linear over the concentration range of 20-10,000 ng/mL (r(2) > 0.99). The intra-batch and inter-batch accuracy for nifekalant hydrochloride at four concentrations were 93.14-100.47% and 96.12-103.77%, respectively. The relative standard deviations were less than 15%. The method was successfully applied to a pharmacokinetic study after the intravenous administration of nifekalant hydrochloride to beagle dogs.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Pirimidinonas/sangue , Pirimidinonas/farmacocinética , Animais , Cães , Feminino , Análise dos Mínimos Quadrados , Extração Líquido-Líquido , Masculino , Pirimidinonas/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Eur J Drug Metab Pharmacokinet ; 36(2): 79-85, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21547451

RESUMO

In the present study, an in situ rat model was employed to systemically investigate the absorption of phillyrin and forsythiaisde. Three concentrations of phillyrin (0.2, 0.4 and 1.5 mg) were tested and the results showed that phillyrin cannot be absorbed in the digestive tract. The absorption rates of forsythiaside in stomach were 7.773, 7.228 and 6.751% h(-1) for 0.5, 1 and 2.5 mg, and no significant difference was found in different concentrations. The absorptions of forsythiaside in intestine were investigated in different concentrations and different absorption sites. The mean P% were 6.618, 7.199, 9.210 and 9.747% h(-1) of forsythiaside in intestine for 0.25, 0.5, 1, 2.5 mg dosage, and the statistical analysis showed that the absorption had no relation with concentration. In addition, in different digestive segments, the mean P% were 7.528, 8.382, 8.191, 9.109 and 6.908% h(-1) for the gastric, duodenum, jejunum, ileum and colon, respectively. No statistical differences of absorption were found for forsythiaside among different digestive segments indicated no specific absorption site was found.


Assuntos
Anti-Infecciosos/farmacocinética , Glucosídeos/farmacocinética , Glicosídeos/farmacocinética , Absorção Intestinal/fisiologia , Algoritmos , Animais , Anti-Infecciosos/administração & dosagem , Mucosa Gástrica/metabolismo , Glucosídeos/administração & dosagem , Glicosídeos/administração & dosagem , Técnicas In Vitro , Masculino , Perfusão , Permeabilidade , Ratos , Ratos Sprague-Dawley , Ratos Wistar
17.
Eur J Drug Metab Pharmacokinet ; 36(1): 41-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21336515

RESUMO

The study was to investigate the absorption mechanism and transport modulation of phillyrin by P-gp in Caco-2 cells and MDR1-MDCKII cells. Three concentrations of phillyrin were tested in transport studies. The absorptive transports of phillyrin in the two cell models were not concentration-dependent which indicated passive diffusion as the dominating process in the test concentrations. The absorptive P (app) were 7.15, 6.39 and 10.03 × 10(-6) cm s(-1), respectively, for different concentrations (2.2, 4.8 and 8.4 µg ml(-1)) in Caco-2 cells. And the low absorptive P (app) was consistent with the low oral bioavailability of phillyrin observed in pharmacokinetic experiments. In transport inhibition experiment, the efflux inhibitors, verapamil and GF120918 can increase the absorption of phillyrin in Caco-2 cells which suggested the involvement of efflux transporters. In the further inhibition experiment in MDR1-MDCKII cells, the absorption was greatly increased and the efflux of phillyrin was competitively inhibited by verapamil and GF120918, which confirmed the involvement of P-gp in the efflux of phillyrin.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Glucosídeos/farmacocinética , Absorção , Animais , Transporte Biológico , Células CACO-2 , Linhagem Celular , Cães , Humanos , Camundongos , Temperatura
18.
Chin J Integr Med ; 16(3): 252-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20694781

RESUMO

OBJECTIVE: To evaluate the improvement of Kangshuai Yizhi Formula I ( I, KYF I) on: the learning and memory dysfunction in mice, and on the mechanism of the hippocampal cholinergic system and the nervous system of monoamine which are closely related to learning and memory function. METHODS: Mice: in the low-, middle-, and high-dose KYF I groups were given low-, middle-, and high-dose KYF, respectively, by gastrogavage for 35 successive days. Animals in the control group and the model group were treated with distilled water. The acute learning and memory dysfunction model was established by injection of scopolamine from day 31, and Morris water maze was used to assess the behavior performance of scopolamine-induced model mice for five days. The activities of acetylcholinesterase (AChE), choline acetyl transferase (ChaT) and the content of monoamine neurotransmitters in hippocampus were measured. The activity of monoamine oxidase (MAO) in hippocampus and serum was also detected. RESULTS: (1) Compared with the control group, the: mean escape latency was shortened, and the frequency across the platform and the staying time at the platform area on the 5th day were decreased in the model group by Morris water maze test. The activities of AChE and MAO were increased, and the ChaT activity and monoamine neurotransmitter content were decreased as well. (2) The escape latency for 4 days in the low-, middle-, and high-dose KYF I groups was significantly shortened than that in the model group, with the shortest latency in the high-dose KYF I group (P<0.05, P<0.01). The frequency across the platform was significantly increased and the staying time at the platform was significantly prolonged in the middle- and high-dose KYF I groups (P<0.05, P<0.01). (3) As compared with the model group, the activity of ChaT and the content of monoamine neurotransmitters in the hippocampus were significantly increased, and the activities of AchE and MAO were significantly decreased in the hippocampus in the high-dose KYF I group (P<0.01). CONCLUSIONS: High-dose KYF I can significantly improve the learning and memory dysfunction: induced by scopolamine in mice. Its mechanism may be related to improving the central cholinergic system and regulating the hippocampal monoamine neurotransmitters.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Aprendizagem/efeitos dos fármacos , Transtornos da Memória/tratamento farmacológico , Escopolamina/toxicidade , Acetilcolinesterase/metabolismo , Alpinia , Animais , Comportamento Animal/efeitos dos fármacos , Colina O-Acetiltransferase/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/enzimologia , Hipocampo/patologia , Masculino , Transtornos da Memória/sangue , Transtornos da Memória/enzimologia , Transtornos da Memória/fisiopatologia , Camundongos , Monoaminoxidase/sangue , Neurotransmissores/metabolismo , Extratos Vegetais , Tempo de Reação , Fatores de Tempo
19.
Dongwuxue Yanjiu ; 31(3): 319-27, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20672422

RESUMO

Acclimatization to winter conditions is an essential prerequisite for survival of small passerines. Seasonal changes in a bird's physiology and behavior are considered to be part of an adaptive strategy for survival and reproductive success. Changes in photoperiod, ambient temperature and food availability trigger seasonal acclimatization in physiology and behavior of many birds. In the present study, seasonal adjustments in several physiological, hormonal, and biochemical markers were examined in wild-captured Chinese bulbuls (Pycnonotus sinensis) from the Zhejiang Province in China. Oxygen consumption was measured using the closed-circuit respirometer containing 3.6 L animal chambers. State-4 respiration in liver and muscle mitochondria was measured at 30 degree with a Clark electrode. The activities of cytochrome C oxidase (COX) in liver and muscle were measured polarographically at 30 degree using a Clark electrode. The protein content of mitochondria was determined by the Folin phenol method, with bovine serum albumin as standard. In winter sparrows had higher body mass and basal metabolic rate (BMR). The contents of mitochondrial protein in liver, and state-4 respiration and COX activity in liver and muscle increased significantly in winter. Circulating level of serum triiodothyronine (T3) was significantly higher in winter than in summer. Together, these data suggest that Chinese bulbuls mainly coped with cold by enhancing thermogenic capacities through increased activity of respiratory enzymes activities. The results support the view that prominent winter increases in BMR are manifestations of winter acclimatization in Chinese bulbuls and that seasonal variation in metabolism in bulbuls is similar to that in other small wintering birds.


Assuntos
Aclimatação , Consumo de Oxigênio , Temperatura , Termogênese , Animais , China , Estações do Ano
20.
Eur J Drug Metab Pharmacokinet ; 34(2): 79-83, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19645216

RESUMO

The objective of the present study was to firstly investigate the in vivo pharmacokinetics of phillyrin and forsythiaside in beagle dog. On I.V. administration, a rapid distribution was observed and followed by a slower elimination for phillyrin and forsythiaside. The mean t(1/2Z) was 49.99, 34.87 and 43.81 min for 0.19, 0.70 and 1.43 mg/kg of phillyrin, and 60.90, 64.30, 57.99 min for 0.62, 1.39 and 5.52 mg/kg of forsythiaside respectively. And the AUC(o-t) increased linearly from 36.51 to 160.22 microg x min/ml of phillyrin and from 50.63 to 681.08 microg x min/ml after the three dosage administrated. In the range of the dose examined, the pharmacokinetics of phillyrin and forsythiaside in beagle dog was based on first order kinetics. Although both drugs were widely distributed to various tissues in the dog, no concerns about extensive binding to tissues that may be consumed by the public should a dog be exposed to phillyrin and forsythiaside according to the rapid elimination.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Glucosídeos/farmacocinética , Glicosídeos/farmacocinética , Animais , Área Sob a Curva , Cães , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/administração & dosagem , Glucosídeos/administração & dosagem , Glicosídeos/administração & dosagem , Meia-Vida , Injeções Intravenosas , Distribuição Tecidual
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