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1.
Artigo em Inglês | MEDLINE | ID: mdl-37068313

RESUMO

LQFM018 is a novel antineoplastic prototype, showing an expressive drug-triggered K562 leukemic cells death mechanism, through necroptotic signaling. Due to its promising effect, this study aimed to evaluate the pharmacokinetics of LQFM018 in rats, using a new validated bioanalytical LC-MS/MS-based method. Chromatographic column was an ACE® C18 (100 mm × 4.6 mm, 5 µm) eluted by a mobile phase composed of ammonium acetate 2 mM and formic acid 0.025%:methanol (50:50, v/v), under flow of 1.2 mL/min and injection volume of 3.0 µL. LQFM018 was extracted from rat plasma by a simple liquid-liquid method, using MTBE solvent. Rats were administered intraperitoneally at LQFM018 100 mg/kg dose and blood samples were collect at times of 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 h. Bioanalytical-LC-MS/MS-based method was rapid, high throughput and sensitive with a good linearity ranging from 10 (LLOQ) to 15000 ng/mL, besides precise and accurate, ranging of 0.8-7.3% and 96.8-107.6%, respectively. The prototype LQFM018 was rapid and well absorbed, and highly distributed, apparently due to its high lipid solubility. These features are primordial for an anticancer agent in the treatment of deep tumors, such as bone marrow neoplasms, in which the drug might permeate easily tissue barriers. Also, LQFM018 has demonstrated a high clearance, according to a low t1/2in rats, indicating a relative fast elimination phase related to a possible intense hepatic biotransformation. These information support further studies to establish new understands on pharmacokinetics of promising antineoplastic prototype LQFM018 from preclinical and clinical evaluations.


Assuntos
Antineoplásicos , Espectrometria de Massas em Tandem , Ratos , Animais , Cromatografia Líquida/métodos , Piperazina , Espectrometria de Massas em Tandem/métodos , Piperazinas , Reprodutibilidade dos Testes
2.
Naunyn Schmiedebergs Arch Pharmacol ; 394(8): 1703-1711, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34014349

RESUMO

Crotamine is a polypeptide toxin isolated from rattlesnake venom. Although several studies have been developed identifying many biological effects of isolated crotamine, none of them evaluated its acute toxicity, antinociceptive, and anti-inflammatory activities through oral administration. All in vivo experiments from this study were performed in mice. The up-and-down procedure and hippocratic screening were carried out to evaluate possible pharmacological and toxic effects. Antinociceptive and anti-inflammatory activities of this toxin were evaluated using acetic acid-induced abdominal writhing, formalin-induced pain assays, croton oil-induced ear edema, and carrageenan-induced pleurisy. Crotamine did not cause lethality or signs of intoxication up to the maximum dose tested (10.88 mg/kg). The number of contortions was reduced significantly by 34, 57, and 74% at the oral doses of 0.08, 0.16, and 0.32 mg/kg, respectively. At the dose of 0.16 mg/kg, crotamine decreases pain time-reactivity at neurogenic phase by 45% and at inflammatory phase by 60%. Also, crotamine elicited antiedematogenic activity through the attenuation of the croton oil-induced ear edema by 77%. In the carrageenan-induced pleurisy, the leukocyte, neutrophil, and mononuclear cell migration to the lesion site were reduced by 52%, 46%, and 59%, respectively. Altogether, crotamine demonstrated in vivo antinociceptive and anti-inflammatory effect through acute oral administration, generating an anti-migratory mechanism of action at non-toxic doses.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Venenos de Crotalídeos/farmacologia , Administração Oral , Analgésicos/administração & dosagem , Analgésicos/toxicidade , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/toxicidade , Carragenina , Venenos de Crotalídeos/administração & dosagem , Venenos de Crotalídeos/toxicidade , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Edema/tratamento farmacológico , Edema/patologia , Masculino , Camundongos , Dor/tratamento farmacológico , Pleurisia/tratamento farmacológico , Pleurisia/patologia , Testes de Toxicidade Aguda
3.
Biosensors (Basel) ; 11(3)2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33810105

RESUMO

In this work, we developed an enzymatic voltammetric biosensor for the determination of catechin and gallic acid in green tea and kombucha samples. The differential pulse voltammetry (DPV) methodology was optimized regarding the amount of crude enzyme extract, incubation time in the presence of the substrates, optimal pH, reuse of the biosensor, and storage time. Samples of green tea and kombucha were purchased in local markets in the city of Goiânia-GO, Brazil. High performance liquid chromatography (HPLC) and Folin-Ciocalteu spectrophotometric techniques were performed for the comparison of the analytical methods employed. In addition, two calibration curves were made, one for catechin with a linear range from 1 to 60 µM (I = -0.152 * (catechin) - 1.846), with a detection limit of 0.12 µM and a quantification limit of 0.38 µM and one for gallic acid with a linear range from 3 to 60 µM (I = -0.0415 * (gallic acid) - 0.0572), with a detection limit of 0.14 µM and a quantification limit of 0.42 µM. The proposed biosensor was efficient in the determination of phenolic compounds in green tea.


Assuntos
Técnicas Biossensoriais , Fungos/isolamento & purificação , Chá de Kombucha/microbiologia , Chá/microbiologia , Calibragem , Catequina/análise , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Ácido Gálico/análise , Chá de Kombucha/análise , Fenóis/análise , Extratos Vegetais , Espectrofotometria , Chá/química
4.
Neuropeptides ; 81: 102027, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32059939

RESUMO

Mastoparan-L (mast-L) is a cell-penetrating tetradecapeptide and stimulator of monoamine exocytosis. In the present study, we evaluated the anxiolytic-like effect of mast-L. Preliminary pharmacological tests were conducted to determine the most appropriate route of administration, extrapolate dose and detect potential toxic effects of this peptide. Oral and intracerebroventricular administration of mast-L (0.1, 0.3 or 0.9 mg.kg-1), diazepam (1 or 5 mg.kg-1), buspirone (10 mg.kg-1) or vehicle 10 mL.kg-1 was carried out prior to the exposure of mice to the anxiety models: open field, light-dark box and elevated plus-maze. To characterize the mechanism underlying the antianxiety-like effect of mast-L, pharmacological antagonism, blood plasma analysis, molecular docking, and receptor binding assays were performed. The absence of a neurotoxic sign, animal's death as well as lack of significant changes in the relative organ weight, hematological and biochemical parameters suggest that mast-L is relatively safe. The anxiolytic-like effect of mast-L was attenuated by flumazenil (antagonist of benzodiazepine binding site) and WAY100635 (selective antagonist of 5-HT1A receptors) pretreatments. Mast-L reduced plasma corticosterone and lowered the scoring function at GABAA -18.48 kcal/mol (Ki = 155 nM), 5-HT1A -22.39 kcal/mol (Ki = 130 nM), corticotropin-releasing factor receptor subtype 1 (CRF1) -11.95 kcal/mol (Ki = 299 nM) and glucocorticoid receptors (GR) -14.69 kcal/mol (Ki = 3552 nM). These data fit the binding affinity (Ki) and demonstrate the involvement of gabaergic, serotonergic and glucocorticoid mechanisms in the anxiolytic-like property of mast-L.


Assuntos
Ansiolíticos/administração & dosagem , Ansiolíticos/farmacologia , Ansiedade/metabolismo , Glucocorticoides/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Serotonina/metabolismo , Venenos de Vespas/administração & dosagem , Venenos de Vespas/farmacologia , Ácido gama-Aminobutírico/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Feminino , Masculino , Camundongos , Receptor 5-HT1A de Serotonina/metabolismo , Receptores de GABA-A/metabolismo
5.
Rev. bras. farmacogn ; 28(4): 414-420, July-Aug. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-958891

RESUMO

Abstract Trembleya parviflora (D. Don) Cogn., Melastomataceae, also known as "quaresmeira-branca", is a subshrub that is commonly used to treat verminosis, scabies, dermatoses, rheumatism, vaginal infections, ulcerations and wounds. The aim of this work was to perform a morphological study of T. parviflora, evaluate the composition and chemical variability of the volatile oils from the leaves, perform phytochemical screening of the powder from the leaves and to define parameters for quality control of the plant material. Macroscopic characterization of T. parviflora was carried out by naked eye in Serra dos Pireneus, Pirenópolis, Goiás for 12 months. Volatile oils were subjected to hydrodistillation with Clevenger apparatus and analyzed by gas chromatography-mass spectrometry. Phytochemical screening and ash and volatile compound content determination were performed by conventional techniques. T. parviflora has simple, oppositely crossed and petiolate leaves. The inflorescence of this plant is a cyme. The presence of coumarins, steroids, triterpenes, flavonoids and tannins was observed. The total ash content was 4.05 ± 0.02%; the insoluble ash content was 0.10 ± 0.03%; and the volatile compound content was 9.53 ± 0.02%. The major compounds present in the volatile oils were α-terpineol (2.7-16.5%), α-pinene (0.6-25.4%), β-pinene (2.7-23.1%), sabinene (1.2-14.1%), acetoxyeudesman-4-α-ol (0.6-6.3%) and 2,4a-8,8-tetramethyldecahydrocyclopropanaphtalene (2.4-24.4). Two clusters were identified: Cluster I represented the period with low levels of rainfall, and Cluster II represented the period with high levels of rainfall. This study provides data that can be applied for the quality control of powdered leaves and is the first description of the chemical composition and variability of the volatile oils from the leaves of T. parviflora.

6.
Rev. bras. farmacogn ; 25(5): 522-525, Sept.-Oct. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-765079

RESUMO

ABSTRACTThe oil from seeds of Dipteryx alata Vogel, Fabaceae, popularly known as baru, was extracted by hydraulic and continuous screw pressing. A total of eleven chemical constituents obtained by hydraulic pressing, including steroids, mono and sesquiterpenes and tocopherol derivatives were identified by gas chromatography–tandem mass spectrometry (GC–MS). Compounds limonene, β-elemene, γ-elemene, α-caryophyllene, β-caryophyllene, campesterol, stigmasterol, β-sitosterol and cycloartenol are being described for the first time in the baru oil.

7.
Ther Drug Monit ; 37(1): 66-70, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25588069

RESUMO

BACKGROUND: Busulfan is an alkylating agent used for conditioning patients undergoing hematopoietic stem cell transplantation with a narrow therapeutic range and highly variable pharmacokinetics. High concentrations induce toxicity, especially hepatic veno-occlusive disease, also referred to as sinusoidal obstruction syndrome. This study aimed to assess busulfan pharmacokinetic variability in pretransplant conditioning regimens using an analytical method validated by high-performance liquid chromatography coupled to diode array detector (HPLC/PDA). METHODS: Eight patients who used the test dose (TD) of 1 mg/kg busulfan 10 days before conditioning were included, and 10 serial blood samples were collected to determine: the elimination half-life (t1/2), total area under the curve (AUCT), total clearance (Cl(T)/F), and plasma concentration at steady state (C(ss)), using a monocompartmental model and first-order kinetics. The instrumental conditions were: HPLC/PDA Shimadzu, column ACE C18 (150 mm × 4 mm); methanol/water/acetonitrile (65:20:15) eluent flow rate of 1 mL/min; 1,6-bis-(methanesulfonyloxy)-hexane; UV λ = 276 nm; analysis time 17 minutes; and derivatization with sodium diethylcarbamate. The dose was adjusted, and 4 blood samples per day were collected at days 2, 3, and 4 of treatment for new plasma determinations. RESULTS: Four patients needed higher doses; the mean dose administered was 1.02 ± 0.19 mg/kg. Mean results at TD: t1/2 = 2.88 ± 0.5 hours; Cl(T)/F = 0.18 ± 0.03 L · h(-1) · kg(-1); AUC(T) = 5461.00 ± 961.15 ng · mL(-1) · h(-1); and C(ss) = 911.3 ± 159.8 ng/mL. Mean results of samples collected during conditioning: t1/2 = 3.21 ± 0.9 hours; Cl(T)/F = 0.13 ± 0.02 L · h(-1) · kg(-1); AUC(T) = 7571 ± 1705 ng · mL(-1) · h(-1); and C(ss) = 1262.0 ± 284.3 ng/mL. CONCLUSIONS: High variability in the assessed pharmacokinetic parameters was observed, with a 38% variation in C(ss) between TD and conditioning regimen; Cl(T)/F decreased by 30%, suggesting drug accumulation after multiple-dose regimen. Although being lower than reported in the literature, this variation may be associated with toxicity of the proposed treatment, justifying patient monitoring and enhancing validity of previous pharmacokinetic evaluation using TD regimen.


Assuntos
Bussulfano/administração & dosagem , Bussulfano/farmacocinética , Transplante de Células-Tronco Hematopoéticas/métodos , Imunossupressores/administração & dosagem , Imunossupressores/farmacocinética , Adolescente , Adulto , Área Sob a Curva , Bussulfano/uso terapêutico , Cromatografia Líquida de Alta Pressão , Feminino , Meia-Vida , Humanos , Imunossupressores/uso terapêutico , Indicadores e Reagentes , Leucemia/metabolismo , Leucemia/terapia , Masculino , Pessoa de Meia-Idade , Medicina de Precisão , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto Jovem
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