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1.
Zhongguo Zhong Yao Za Zhi ; 49(3): 728-734, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621876

RESUMO

Mesona chinensis is a common medicinal and edible plant in the Lingnan region of China, which has extensive pharmacological activity. However, the study of its chemical constituents is not sufficient. In this study, a variety of modern chromatographic separation techniques were used to isolate two compounds from 95% ethanol extract of the grass parts of M. chinensis. Their absolute configurations were determined by ultraviolet spectroscopy(UV), infrared spectroscopy(IR), high resolution mass spectrometry(HR-ESI-MS), 1D and 2D nuclear magnetic resonance(1D NMR and 2D NMR), and single-crystal X-ray diffraction(SC-XRD). Specifically, they were two new benzoyl-sesquiterpenes and named mesonanol A and mesonanol B, respectively. The results of the pharmacological activity evaluation showed that neither of the two new compounds showed obvious antiviral and anti-inflammatory activities.


Assuntos
Lamiaceae , Sesquiterpenos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Espectrofotometria Infravermelho , Estrutura Molecular
2.
Environ Sci Technol ; 57(10): 4219-4230, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36848599

RESUMO

The transport of ferrihydrite colloid (FHC) through porous media is influenced by anions (e.g., PO43-) and cations (e.g., Ca2+) in the aqueous environment. This study investigated the cotransport of FHC with P and P/Ca in saturated sand columns. The results showed that P adsorption enhanced FHC transport, whereas Ca loaded onto P-FHC retarded FHC transport. Phosphate adsorption provided a negative potential on the FHC, while Ca added to P-FHC led to electrostatic screening, compression of the electric double layer, and formation of Ca5(PO4)3OH followed by heteroaggregation at pH ≥ 6.0. The monodentate and bidentate P surface complexes coexisted, and Ca mainly formed a ternary complex with bidentate P (≡(FeO)2PO2Ca). The unprotonation bidentate P at the Stern 1-plane had a considerable negative potential at the Van der Waals molecular surface. Extending the potential effect to the outer layer of FHC, the potential at the Stern 2-plane and zeta potential exhibited a corresponding change, resulting in a change in FHC mobility, which was validated by comparison of experimental results, DFT calculations, and CD-MUSIC models. Our results highlighted the influence of P and Ca on FHC transport and elucidated their interaction mechanisms based on quantum chemistry and colloidal chemical interface reactions.


Assuntos
Cálcio , Fósforo , Adsorção , Eletricidade Estática , Coloides/química , Porosidade
3.
Ecotoxicol Environ Saf ; 249: 114402, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36516624

RESUMO

Excessive application of fertilizers has caused a high load of phosphorus (P) in the North China Plain. The fate of P and its effects on aquatic ecosystems depend on its chemical speciation in soils. However, few studies systematically investigated the transport and retardation of different P species in the fluvo-aquic soil. In this study, the transport of inorganic P (orthophosphate, PO4), organic P (phytic acid, PA) and particulate P (hydroxyapatite nanoparticles, nHAP) in the fluvo-aquic soil were investigated by column experiments, and their retardation from major soil components such as kaolin, CaCO3, Al2O3, and goethite (GT) was also investigated by monitoring breakthrough curves and fitting transport models. The transport of P species in fluvo-aquic soil followed the order of PO4 > PA > nHAP. A high fraction of increased clay and mineral particle-associated P (P-E) was observed for PO4 and PA; while significant Ca-associated P (P-Ca) for nHAP. Under the experimental conditions, both CaCO3 and GT were the most influential factors for PO4, PA, and nHAP retention. Goethite strongly inhibited PO4 transport due to its high PO4 adsorption capacity, while CaCO3 strongly inhibited PA transport due to its strong association with PA under alkaline conditions. Both CaCO3 and GT can severely inhibit nHAP transport due to the favorable electrostatic conditions as well as the Ca2+ bridging effect. These results indicated that CaCO3 played a key role in regulating the retention of organic P and particulate P in the calcareous soil, and also suggested the important role of Fe (hydr)oxides in controlling the transport of inorganic P, which could out-compete that of CaCO3.


Assuntos
Fósforo , Solo , Ecossistema , Durapatita
4.
Langmuir ; 37(40): 11707-11715, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34570511

RESUMO

The unconjugated bilirubin (BR) may penetrate through the cell membrane and cause a severe cytotoxicity. However, the molecular mechanism underlying the penetration of BR into the cell membrane is still largely unknown. In this work, we systematically investigate the interaction of BR and a lipid bilayer under different conditions by using all-atom molecular dynamics simulations. It is found that BR at the Z,Z conformation can easily enter into the interior of the lipid bilayer due to its hydrophobicity. However, when BR transforms from the Z,Z conformation to the E,E conformation (after the blue-light emission), its penetration ability is greatly reduced (especially at its ionized state). This study may offer useful physical insights into the effect of phototherapy on the penetration behavior and the cytotoxicity of the unconjugated BR.


Assuntos
Bilirrubina , Bicamadas Lipídicas , Membrana Celular , Conformação Molecular , Simulação de Dinâmica Molecular
5.
Chemosphere ; 283: 131102, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34146872

RESUMO

Arsenic (As) and cadmium (Cd) are unnecessary metal(loids) toxic at high concentration to plants and humans, hence lessening their rice grain accumulation is crucial for food security and human healthiness. Charred eggshell (EB), corncob biochar (CB), and eggshell-corncob biochar (ECB) were produced and amended to As and Cd co-polluted paddy soil at 1% and 2% application rates to alleviate the metal(loids) contents in rice grains using pot experiments. All the amendments increased paddy yields at 1%, while EB at 2% significantly reduced the yields compared to untreated control. The resulting yield loss in 2%EB was from the combined effects of its high CaCO3 supplementation, and the increment of rhizosphere soil pH which could insolubilize plant nutrients. The amendments were inefficient in decreasing rice grain As (AsGrain), but all the treatments significantly reduced the rice grain Cd (CdGrain) at both 1% (44.4-77.1%) and 2% (79.8-91.5%) application rates compared to that of control. Regression analysis for contribution weights of control factors revealed that rhizosphere soil Eh and pH were vital influential factors regulating the AsGrain, whereas porewater Cd was main factor controlling CdGrain accumulation. These investigations indicated that the Ca-enriched eggshell-corncob biochar even at high application rate (i.e., 2%ECB) could be a potential tactic for grain accumulation remediation of the cationic pollutant (i.e., Cd) from the paddy soil to rice grain scheme with concurrent increase in rice yields.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Arsênio/análise , Cádmio/análise , Cálcio , Carvão Vegetal , Humanos , Solo , Poluentes do Solo/análise
6.
Chemosphere ; 276: 130012, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34088086

RESUMO

Iron (Fe) minerals, organic matter (OM), and pH can effectively regulate phosphorus (P) transport in the soil. However, their respective contributions in this regard are still unclear. In this study, P transport in soil columns was investigated by monitoring breakthrough curves and transport model fitting, and the contributions of Fe and total organic carbon (TOC) concentrations, as well as pH to P retention, were determined using multiple linear regression (MLR). The results showed that the rate of P transport in Fe-rich laterite soil was significantly lower (retardation factor R = 458.5) than that in the other soil types (R = 108.4-247.6). Additionally, it was observed that OM formed rate-limited adsorption sites, causing the rapid release of labile P, and owing to P release and readsorption. Even though more significant P releases were observed, chernozem soil had an obvious inhibiting effect on P transport owing to its relatively high Fe content, and the high P-Fe increment (48.9-90.4%) indicated the essential role of Fe minerals in P immobilization. Further, P was readily transported in natural or artificially modified fluvo-aquic soils with high calcium concentrations, and it was also observed that the convection-dispersion equation (CDE) and Thomas models were suitable for describing P retardation and adsorption, respectively. Furthermore, the contribution weights of Fe and TOC concentrations as well as pH to P retardation, based on MLR calculations, were approximately 1.0, -0.3, and -0.2, respectively. Our findings can support the control of eutrophication pollution caused by P leaching.


Assuntos
Poluentes do Solo , Solo , Adsorção , Eutrofização , Fósforo , Poluentes do Solo/análise
7.
Biomed Pharmacother ; 133: 111015, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33232924

RESUMO

AIMS: Over-expression of CXCR4 activates nuclear translocation of NF-κB, induces high expression of NLRP3, GSDMD, IL-1ß and IL-18, which promotes severe inflammatory response following myocardial infarction. Previous studies revealed inflammation induces anxiety after myocardial infarction. The Chaihujialonggumuli granule has anti-inflammatory properties and could tranquillize mind. But the mechanism of its efficacy remains unknown. This study was to investigate the possible mechanism of BFG on cardioprotective and anxiolytic. METHODS: The expression of CXCR4, NF-κB, NLRP3and GSDMD was measured with western-blot, QRT-PCR. The expression location of CXCR4, NLRP3, GSDMD were determined by immunohistochemistry. IL-1ß、IL-18 in the peripheral blood were measured by ELISA. HE staining, Masson staining and transmission electron microscopy were used to observe morphological changes of cardiomyocytes. Echocardiography was used to assess cardiac function after cardiac surgery. Elevated cross maze test and open field test were used to evaluate behaviours. Western blot was used to detect the protein expressions of 5-HT, DA, IL-1ß, IL-18 and neuron damage was investigated by Nissl staining in the hippocampus. RESULTS: The up-regulation of CXCR4, NF-κB, NLRP3 and GSDMD were found in the infarcted area after left coronary artery ligation. Pathological staining and analysis showed that more severe inflammatory cytokines infiltration, myocardial fibrosis, were found in myocardial tissue of the complex group rats. And when compared to the sham group, the levels of IL-1ß, IL-18 was increased of the complex group in both peripheral blood and brain. Behavioural test and echocardiography indicated that the rats in complex group exploration behaviours was significantly reduced, and with poor cardiac functional recovery. The AMD3100 had an inhibitory impact of CXCR4 on the activition of its downstream effectors, alleviating inflammatory reaction. Furthermore, the BFG decreased the expression level of CXCR4, NF-κB, GSDMD, NLRP3 in the infarcted area after myocardial infarction, when compared to the complex group. The assays in the brain indicated the BFG suppressed expression and activity of IL-1ß, IL-18, and improved 5-HT and DA synthesis. CONCLUSIONS: In sum, our study indicated that BFG may reduce inflammation, treat co-existing anxiety after myocardial infarction through inhibition of CXCR4/NF-κB/GSDMD signalling.


Assuntos
Ansiolíticos/farmacologia , Anti-Inflamatórios/farmacologia , Ansiedade/prevenção & controle , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Infarto do Miocárdio/tratamento farmacológico , Miocárdio/metabolismo , NF-kappa B/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Receptores CXCR4/metabolismo , Animais , Ansiedade/metabolismo , Ansiedade/fisiopatologia , Ansiedade/psicologia , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Citocinas/metabolismo , Modelos Animais de Doenças , Comportamento Exploratório/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , NF-kappa B/genética , Proteínas de Ligação a Fosfato/genética , Ratos Sprague-Dawley , Receptores CXCR4/genética , Transdução de Sinais , Função Ventricular Esquerda/efeitos dos fármacos
8.
Water Res ; 157: 372-380, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30974286

RESUMO

Among natural organic matter (NOM), oxyanions and metal (hydr)oxides, a complicated interaction exists in natural aquatic and terrestrial systems and in waste waters. Effects of seven types of NOM (four humic acids (HA), three fulvic acids (FA)) that vary in properties on the adsorption of oxyanions, including phosphate, arsenate and arsenite, at goethite-water interface were quantitatively studied. Results show that the adsorption of oxyanions to goethite is decreased by the presence of NOM, especially for phosphate and arsenate at low pH. In general, the effects of the three FA are similar, which are more effective than HA in reducing oxyanion adsorption at low pH (<6). Differences were observed between the four HA in their competition with oxyanions. The adsorption of phosphate, arsenate and arsenite in the presence of NOM are well described with both the NOM-CD (CD: Charge Distribution) and LCD (Ligand and Charge Distribution) model. The NOM-CD model is relatively simple to use, whereas the LCD model can better reveal different factors in the interaction, including the spatial distribution of adsorbed NOM on oxide surface. According to these two models: site density of carboxylic groups, protonation constant of carboxylic groups, and particle size of NOM are major properties of NOM determining its effect on oxyanion adsorption to oxides. At relatively low loadings, morphological change of adsorbed NOM takes place, and the degree of morphological change of adsorbed NOM depends on the particle size, site density of carboxylic groups and aromaticity of NOM. The influence of particle size on the interaction becomes more important at higher NOM loadings. The results suggested that the fixation or removal efficiency of phosphate, arsenate and arsenite with iron oxides (e.g. goethite) can be significantly decreased by the presence of NOM, especially when NOM rich in acidic and aromatic groups.


Assuntos
Arsênio , Compostos de Ferro , Adsorção , Minerais , Fósforo , Água
9.
Int J Mol Med ; 43(2): 717-726, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30535505

RESUMO

Oxidative stress and neuroinflammation are important in the pathogenesis of ageing and age­related neurodegenerative diseases, including Alzheimer's disease. NADPH oxidase 2 (NOX2) is a major source of reactive oxygen species (ROS) in the brain. The nucleotide­binding oligomerisation domain (NOD)­like receptor protein 1 (NLRP1) inflammasome is responsible for the formation of pro­inflammatory molecules in neurons. Whether the NOX2­NLRP1 inflammasome signalling pathway is involved in neuronal ageing and age­related damage remains to be elucidated. Ginsenoside Rg1 (Rg1) is a steroidal saponin found in ginseng. In the present study, the primary hippocampal neurons were treated with H2O2 (200 µM) and Rg1 (1, 5 and 10 µM) for 24 h to investigate the protective effects and mechanisms of Rg1 on H2O2­induced hippocampal neuron damage, which mimics age­related damage. The results showed that H2O2 treatment significantly increased ROS production and upregulated the expression of NOX2 and the NLRP1 inflammasome, and led to neuronal senescence and damage to hippocampal neurons. Rg1 decreased ROS production, reducing the expression of NOX2 and the NLRP1 inflammasome in H2O2­treated hippocampal neurons. Furthermore, Rg1 and tempol treatment significantly decreased neuronal apoptosis and the expression of ß­galactosidase, and alleviated the neuronal senescence and damage induced by H2O2. The present study indicates that Rg1 may reduce NOX2­mediated ROS generation, inhibit NLRP1 inflammasome activation, and inhibit neuronal senescence and damage.


Assuntos
Fármacos do Sistema Nervoso Central/farmacologia , Ginsenosídeos/farmacologia , Hipocampo/patologia , Inflamassomos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Caspase 1/metabolismo , Células Cultivadas , Medicamentos de Ervas Chinesas/farmacologia , Peróxido de Hidrogênio , Inflamassomos/efeitos dos fármacos , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , NADPH Oxidase 2/antagonistas & inibidores , Proteínas NLR/metabolismo , Proteínas do Tecido Nervoso/antagonistas & inibidores , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , beta-Galactosidase/biossíntese
10.
Nutr Cancer ; 68(7): 1151-60, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27618151

RESUMO

The sporoderm-broken spores of Ganoderma lucidum (SBGS) and their extracts exhibited a wide range of biological activities. In the present study, we prepare ethanol/ethanol extract (E/E-SBGS) and ethanol/aqueous extract (E/A-SBGS) from SBGS and examine their antitumor activities against human lung cancer. Our results showed that E/E-SBGS, not E/A-SBGS, inhibited the survival and migration of lung cancer cells in a dose-dependent manner. E/E-SBGS arrested cell cycle at G2/M phase and triggered apoptosis by decreasing the expression and activity of cell cycle regulators, cyclin B1 and cdc2, as well as anti-apoptotic proteins, Bcl-2 and Bcl-xl. Consequently, colony formation of lung cancer cells was markedly blocked by E/E-SBGS at subtoxic concentrations. Oral administration of both E/E-SBGS and SBGS significantly suppressed tumor volume and tumor weight without gross toxicity in mice. Mechanism study showed that E/E-SBGS dose-dependently suppressed the activation of Akt, the mammalian target of rapamycin (mTOR) and their downstream molecules S6 kinase and 4E-BP1 in treated tumor cells. Taken together, these results indicate that the ethanol extract of sporoderm-broken spores of G. lucidum suppresses the growth of human lung cancer, at least in part, through inhibition of the Akt/mTOR signaling pathway, suggesting its potential role in cancer treatments.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Ganoderma/química , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Esporos Fúngicos/química , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Fase G2/efeitos dos fármacos , Ganoderma/fisiologia , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos Nus , Invasividade Neoplásica/patologia , Invasividade Neoplásica/prevenção & controle , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Esporos Fúngicos/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaio Tumoral de Célula-Tronco , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Yao Xue Xue Bao ; 51(5): 786-91, 2016 05.
Artigo em Chinês | MEDLINE | ID: mdl-29878726

RESUMO

An HPLC method was established for the determination of adenosine, γ-aminobutyric acid (GABA) and six flavonoids (calycosin-7-glucoside, ononin, calycosin, isoliquiritigenin, formononetin and medicarpin) in Radix Hedysari. The samples were extracted with methanol by refluxing for 4 h. The HPLC-DAD was performed on a Diamonsil C(18) column (250 mm × 4.6 mm, 5 µm) with acetonitrile-water as the mobile phase. The column temperature was at 40 ℃ and the flow rate was 1.0 m L·min(-1), while the temperature of drift tube was 110.5 ℃ and the nebulizing gas flow was 3.1 L·min-1 for the ELSD system. The results showed all the eight components had good linear relationships (r(2) =0.992 8-1.000 0) in the range of the test concentration. The RSD of precision, stability and repeatability were less than 2%.The average recovery rates were 96.78%-103.45%, and RSD were 0.29%-1.61%.The index component contents of Radix Hedysari form 24 different origins were determined and used as variable factors in clustering analysis. The results were classified into 2 groups basically in accordance with the regional cluster. And the consequence was in consistent with the results of principal component analysis. This HPLC method is simple, shows good sensitive and accurate, and provides the experimental basis for multi-index control of Radix Hedysari. Clustering analysis for Radix Hedysari quality control has a certain reliability and objectivity.


Assuntos
Medicamentos de Ervas Chinesas/química , Fabaceae/química , Flavonoides/isolamento & purificação , Raízes de Plantas/química , Cromatografia Líquida de Alta Pressão , Glucosídeos , Isoflavonas , Controle de Qualidade , Reprodutibilidade dos Testes
12.
Se Pu ; 33(4): 413-8, 2015 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-26292413

RESUMO

The spectrum-effect relationship on anti-hepatic fibrosis effect of Radix Hedysari was explored based on high performance liquid chromatographic technique. Hepatic fibrosis was induced in mice by administering a subcutaneous injection of carbon tetrachloride-peanut oil (4:6, v/v) continuously for 35 d at a interval of 5 d (0.1 mL/10 g). And at the same time of modeling, the different extracts of Radix Hedysari were administered orally once daily at a dose of 10 g/kg. The ethanol extract of Radix Hedysari was specified to be most effective on anti-hepatic fibrosis by determining the levels of alanine aminotransferase, aspartate transami- nase, total-protein, albumin, albumin/globulin (ALT, AST, TP, ALB, and A/G) in serum and relative liver weight. Subsequently, the grey relational degree analysis and partial least squares analysis were employed to reveal the correlation between chromatographic fingerprint of ethanol extract of Radix Hedysari from 10 different geographical origins and its anti-hepatic fibrosis efficacy. The results suggest that most chemical constituents of Radix Hedysari have a high correlation with the effect of anti-hepatic fibrosis (> 0.8), which indicates that the effect is related to the various components in Radix Hedysari. Adenosine, calycosin and ononin in ethanol extract of Radix Hedysari have been identified separately among which adenosine and calycosin made the great contribution to the anti-hepatic fibrosis effect.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Fabaceae/química , Cirrose Hepática/tratamento farmacológico , Animais , Tetracloreto de Carbono , Cromatografia Líquida de Alta Pressão , Glucosídeos/farmacologia , Isoflavonas/farmacologia , Cirrose Hepática/induzido quimicamente , Camundongos , Raízes de Plantas/química
13.
J Sep Sci ; 38(1): 9-17, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25330407

RESUMO

A simple and efficient method was developed for the simultaneous determination of eight isoquinoline alkaloids in methanol extracts of Dicranostigma leptopodum (Maxim) Fedde and the effective fractionation of the alkaloids of D. leptopodum by high-performance liquid chromatography with diode array detection. The chromatographic conditions were optimized on a SinoChrom ODS-BP column to obtain a good separation of the four types of alkaloid analytes, including two aporphines (isocorydine, corydine), two protopines (protopine and allocryptopine), a morphine (sinoacutine), and three quaternary protoberberine alkaloids (berberrubine, 5-hydroxycoptisine, and berberine). The separation of these alkaloids was significantly affected by the composition of the mobile phase, and particularly by its pH value. Acetonitrile (A) and 0.2% phosphoric acid solution adjusted to pH 6.32 with triethylamine (B) were selected as the mobile phase with a gradient elution. With this method, a new quaternary protoberberine alkaloid was isolated and the two structural isomers (isocorydine and corydine) were baseline separated. The appropriate harvest period for D. leptopodum was also recommended based on our analysis. The method for the effective fraction of the alkaloids of D. leptopodum was optimized under this method with regard to the varying significant pharmacological activities of the alkaloids.


Assuntos
Alcaloides/análise , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/isolamento & purificação , Isoquinolinas/análise , Isoquinolinas/isolamento & purificação , Papaveraceae/química , Alcaloides/isolamento & purificação , Cromatografia Líquida de Alta Pressão/instrumentação
14.
PLoS One ; 6(8): e23237, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21858040

RESUMO

BACKGROUND: ST-246® is an antiviral, orally bioavailable small molecule in clinical development for treatment of orthopoxvirus infections. An intravenous (i.v.) formulation may be required for some hospitalized patients who are unable to take oral medication. An i.v. formulation has been evaluated in three species previously used in evaluation of both efficacy and toxicology of the oral formulation. METHODOLOGY/PRINCIPAL FINDINGS: The pharmacokinetics of ST-246 after i.v. infusions in mice, rabbits and nonhuman primates (NHP) were compared to those obtained after oral administration. Ten minute i.v. infusions of ST-246 at doses of 3, 10, 30, and 75 mg/kg in mice produced peak plasma concentrations ranging from 16.9 to 238 µg/mL. Elimination appeared predominately first-order and exposure dose-proportional up to 30 mg/kg. Short i.v. infusions (5 to 15 minutes) in rabbits resulted in rapid distribution followed by slower elimination. Intravenous infusions in NHP were conducted at doses of 1 to 30 mg/kg. The length of single infusions in NHP ranged from 4 to 6 hours. The pharmacokinetics and tolerability for the two highest doses were evaluated when administered as two equivalent 4 hour infusions initiated 12 hours apart. Terminal elimination half-lives in all species for oral and i.v. infusions were similar. Dose-limiting central nervous system effects were identified in all three species and appeared related to high C(max) plasma concentrations. These effects were eliminated using slower i.v. infusions. CONCLUSIONS/SIGNIFICANCE: Pharmacokinetic profiles after i.v. infusion compared to those observed after oral administration demonstrated the necessity of longer i.v. infusions to (1) mimic the plasma exposure observed after oral administration and (2) avoid C(max) associated toxicity. Shorter infusions at higher doses in NHP resulted in decreased clearance, suggesting saturated distribution or elimination. Elimination half-lives in all species were similar between oral and i.v. administration. The administration of ST-246 was well tolerated as a slow i.v. infusion.


Assuntos
Benzamidas/farmacocinética , Avaliação Pré-Clínica de Medicamentos/métodos , Isoindóis/farmacocinética , Administração Oral , Animais , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Antivirais/farmacocinética , Área Sob a Curva , Benzamidas/administração & dosagem , Benzamidas/efeitos adversos , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Feminino , Humanos , Infusões Intravenosas , Isoindóis/administração & dosagem , Isoindóis/efeitos adversos , Macaca fascicularis , Masculino , Taxa de Depuração Metabólica , Camundongos , Camundongos Endogâmicos BALB C , Coelhos , Fatores de Tempo , Distribuição Tecidual , Tremor/induzido quimicamente
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