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1.
Sci Rep ; 14(1): 1883, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253706

RESUMO

Cigarette smoking delivers a number of heavy metals, including cadmium (Cd), into the body. Bioaccumulation may result in an increase in pathological consequences over time. The assessment of changes in serum Cd concentrations during the treatment of cigarette dependence with cytisine was performed for the first time. Parameters assessing smoking habits, strength of addiction, and effectiveness of therapy were analyzed. Cd was determined before, during, and after the end of treatment. The serum Cd levels were significantly higher in the smokers than in the nonsmokers. Significant differences in Cd concentrations between sampling times in smokers were observed. Individuals who stopped smoking had significantly lower Cd concentrations compared to baseline. A significant positive correlation between the serum Cd before treatment and smoking urges was also obtained. Additionally, salivary Cd determinations were performed before treatment to evaluate the use of this method to assess cigarette addiction. Our findings indicate that Cd can be used as a biomarker of smoking addiction, and provide an alternative assessment of tobacco smoke exposure to other methods. The results provide new knowledge related to Cd concentrations in human body fluids and may play a role in monitoring and assessing the efficacy of cytisine for smoking cessation.


Assuntos
Alcaloides , Fumar Cigarros , Alcaloides Quinolizidínicos , Tabagismo , Humanos , Cádmio , Fumar , Azocinas
2.
Int J Mol Sci ; 24(20)2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37895042

RESUMO

Cytisine (CYT) is a quinolizidine alkaloid used for nicotine addiction treatment. Recent clinical trial data regarding cytisine confirm its high effectiveness and safety as a smoking cessation treatment. CYT's popularity is growing due to its increased availability and licensing in more countries worldwide. This increased use by smokers has also resulted in an urgent need for continued drug research, including developing appropriate analytical methods for analyzing the drug in biological samples. In this study, a simple, fast, and reliable method combining hydrophilic interaction liquid chromatography and electrospray ionization quadrupole time of flight mass spectrometry (HILIC/ESI-QTOF-MS) for the determination of CYT in human serum and saliva was developed and validated. This was undertaken after the previous pre-treatment of the sample using solid-phase extraction (SPE). A hydrophilic interaction liquid chromatography (HILIC) column with a silica stationary phase was used for chromatographic analysis. In a linear gradient, the mobile phase consisted of acetonitrile (ACN) and formate buffer at pH 4.0. The proposed method was fully validated and demonstrated its sensitivity, selectivity, precision, and accuracy. The method was successfully applied to determine CYT in serum and, for the first time, in saliva. The findings indicate that saliva could be a promising non-invasive alternative to measure the free concentration of CYT.


Assuntos
Alcaloides , Saliva , Humanos , Cromatografia Líquida/métodos , Saliva/química , Espectrometria de Massas em Tandem/métodos , Alcaloides Quinolizidínicos , Alcaloides/análise , Cromatografia Líquida de Alta Pressão/métodos
3.
Int J Biol Macromol ; 245: 125544, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37356682

RESUMO

The polymeric cytisine-enriched fibers based on poly(3-hydroxybutyrate) were obtained using electrospinning method. The biocompatibility study, advanced thermal analysis and release of cytisine from the poly(3-hydroxybutyrate) fibers were carried out. The nanofibers' morphology was evaluated by scanning electron microscopy. The formation and description of phases during the thermal processes of fibers by the advanced thermal analysis were examined. The new quantitative thermal analysis of polymeric fibers with cytisine phases based on vibrational, solid and liquid heat capacities was presented. The apparent heat capacity of fibers was measured using the standard differential scanning calorimetry. The quantitative analysis allowed for the study of the glass transition and melting/crystallization process. The mobile amorphous fraction, degree of crystallinity and rigid amorphous fraction were determined depending on the thermal history of semicrystalline polymeric fibers. Furthermore, the cytisine dissolution behaviour was studied. It was observed that the kinetic of the release from polymeric nanofiber is delayed than for the marketed product. The immunosafety of the tested polymeric nanofibers with cytisine was confirmed by the Food and Drug Agency Guidance as well as the European Medicines Agency. The polymeric matrix with cytisine seems to be a promising candidate for the prolonged release formulation.


Assuntos
Nanofibras , Polímeros , Preparações de Ação Retardada/química , Ácido 3-Hidroxibutírico , Polímeros/química , Nanofibras/química , Varredura Diferencial de Calorimetria
4.
Eur J Pharm Sci ; 183: 106397, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36736465

RESUMO

The characterization of cytisine (CYT) and its blends with poly(lactic acid) was performed using thermal analysis, elemental analysis, infrared spectroscopy, and powder X-ray diffractometry. The heat capacities, total enthalpy, and phase transitions of CYT were established from 1.8 to 448.15 K (-271.35 - 175 °C) by advanced thermal analysis. Data were obtained using a Quantum Design Physical Property Measurement System (PPMS) and a differential scanning calorimetry (DSC). The low-temperature heat capacity of the crystalline CYT in the range of 1.8 to 300 K (-271.35 - 26.86 °C) was measured by PPMS and fitted to a theoretical model in the low temperature region below 11 K (-262.15 °C), to orthogonal polynomials in the middle range 5 K < T < 60 K (-268.15 °C < t < -213.15 °C) and to the Debye and Einstein functions in the high range of temperature above 60 K (-213.15 °C). The liquid heat capacity was calculated based on the approximated linear regression data above the molten state of the experimental heat capacity of CYT obtained by the standard DSC measurements, and it was expressed as Cpliquid = 0.0838T + 346.78 J·K-1·mol-1. The calculated heat capacity in the solid state was extended to a higher temperature and was used, together with liquid heat capacity, as the reference baselines for the advanced thermal analysis of CYT. The PPMS and DSC/TMDSC methods are complementary methods for thermal analysis of cytisine. The PPMS method allowed determination of the equilibrium heat capacity in the solid state, which together with the equilibrium heat capacity in the liquid state allowed to analyze of the experimental apparent heat capacity of cytisine obtained based on DSC. The melting temperature and the total heat of fusion of crystalline material were established as 431.8 K (158.65 °C) and 26.5 kJ·mol-1, respectively. The solid and liquid heat capacities and transition parameters of CYT were applied to calculate total enthalpies for fully amorphous and crystalline states. Analyses of DSC and X-ray confirmed the presence of the solid-solid transition linking with not so far described a polymorphism phenomenon of CYT. Based on the thermogravimetric analysis the temperature of degradation of CYT was determined as 460.5 K (187.35 °C). Also, a preliminary thermal analysis of the blends of cytisine and poly(lactic acid) as a new candidate for drug delivery system was presented.


Assuntos
Temperatura Alta , Abandono do Hábito de Fumar , Preparações Farmacêuticas , Temperatura , Varredura Diferencial de Calorimetria
5.
Int J Mol Sci ; 24(3)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36768937

RESUMO

Varenicline (VAR) is a partial agonist of brain α4ß2 nicotinic acetylcholine receptors recommended as a first line pharmacotherapy for smoking cessation. The aim of this study was to examine whether VAR affects the protective activity of four classic antiseizure medications, i.e., carbamazepine (CBZ), phenobarbital (PB), phenytoin (PHT), and valproate (VPA) on maximal electroshock (MES)-induced seizures, which may serve as an experimental model of human-generalized tonic-clonic seizures in mice. VAR administered intraperitoneally (i.p.) at a subthreshold dose of 0.5 mg/kg decreased the protective activity of CBZ against MES-induced convulsions, increasing its median effective dose (ED50) from 10.92 ± 1.0 to 18.15 ± 1.73 mg/kg (p < 0.01). The effect of VAR was dose-dependent because a lower dose of VAR (0.25 mg/kg) failed to antagonize the protective activity of CBZ. VAR administered at the subthreshold dose of 0.5 mg/kg had no impact on the protective activity of PB, PHT, and VPA in the mouse MES model. The inhibitory effect of VAR on the protective activity of CBZ against tonic-clonic convulsions most likely resulted from the pharmacodynamic mechanism(s) and was not associated with the changes in total brain concentrations of CBZ. VAR-evoked alterations in the anticonvulsive activity of CBZ may be of serious concern for epileptic tobacco smokers.


Assuntos
Anticonvulsivantes , Convulsões , Humanos , Camundongos , Animais , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Vareniclina/farmacologia , Vareniclina/uso terapêutico , Eletrochoque/efeitos adversos , Convulsões/tratamento farmacológico , Convulsões/etiologia , Encéfalo , Carbamazepina/farmacologia , Fenobarbital/farmacologia , Fenobarbital/uso terapêutico , Ácido Valproico/farmacologia , Fenitoína , Relação Dose-Resposta a Droga , Modelos Animais de Doenças
6.
Trials ; 23(1): 777, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104702

RESUMO

BACKGROUND: In Australia, tobacco smoking rates have declined but inequalities remain with significantly higher smoking prevalence among low-socioeconomic populations. Clinical trial data suggest vaporized nicotine products (VNPs) aid smoking cessation. Most VNP trials have used refillable tank systems, but newer generation (pod) devices now comprise the largest market share yet have limited clinical trial evidence on safety and effectiveness. This study evaluates the effectiveness, safety and cost-effectiveness of VNPs (pod and tank device) compared with nicotine replacement therapy ([NRT]-gum or lozenge) for smoking cessation. METHODS: This is a two-arm, open-label, superiority, parallel group, randomized controlled trial (RCT) with allocation concealment and blinded outcome assessment. The RCT is conducted at the National Drug and Alcohol Research Centre at the University of New South Wales, Sydney, Australia. Participants are people who smoke daily, are interested in quitting and receive a government pension or allowance (N = 1058). Participants will be randomized (1:1 ratio) to receive 8 weeks of free: VNPs, with pod (40 mg/mL nicotine salt) and tank device (18 mg/mL freebase nicotine) in mixed flavours; or NRT (gum or lozenge; 4 mg). All participants will receive daily text message behavioural support for 5 weeks. Assessments will be undertaken by telephone at baseline, with three follow-up calls (two check-in calls within the first month and final follow-up at 7 months post randomization) to ascertain smoking status, treatment adherence and adverse events. The primary outcome is 6-month continuous abstinence verified by carbon monoxide breath test of ≤5ppm at 7-month follow-up. Safety and cost-effectiveness of VNPs versus NRT will also be evaluated. DISCUSSION: Further data are required to strengthen certainty of evidence for VNPs aiding smoking cessation, particularly for newer generation pod devices. To our knowledge, this trial is the first to offer choice of VNPs and no comparative effectiveness trial data exists for new pod devices. If effective, the findings can inform wider implementation of VNPs to aid smoking cessation in a priority group. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12621000076875. Registered on 29 January 2021.  https://www.anzctr.org.au.


Assuntos
Alcoolismo , Abandono do Hábito de Fumar , Austrália , Análise Custo-Benefício , Humanos , Nicotina/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Abandono do Hábito de Fumar/métodos , Classe Social , Nicotiana , Dispositivos para o Abandono do Uso de Tabaco/efeitos adversos , Resultado do Tratamento
8.
JAMA ; 326(1): 56-64, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34228066

RESUMO

Importance: Cytisine is more effective than placebo and nicotine replacement therapy for smoking cessation. However, cytisine has not been tested against the most effective smoking cessation medication, varenicline, which is associated with adverse events known to lead to discontinuation of therapy. Objective: To examine whether standard cytisine treatment (25 days) was at least as effective as standard varenicline treatment (84 days) for smoking cessation. Design, Setting, and Participants: This noninferiority, open-label randomized clinical trial with allocation concealment and blinded outcome assessment was undertaken in Australia from November 2017 through May 2019; follow-up was completed in January 2020. A total of 1452 Australian adult daily smokers willing to make a quit attempt were included. Data collection was conducted primarily by computer-assisted telephone interview, but there was an in-person visit to validate the primary outcome. Interventions: Treatments were provided in accordance with the manufacturers' recommended dosage: cytisine (n = 725), 1.5-mg capsules taken 6 times daily initially then gradually reduced over the 25-day course; varenicline (n = 727), 0.5-mg tablets titrated to 1 mg twice daily for 84 days (12 weeks). All participants were offered referral to standard telephone behavioral support. Main Outcomes and Measures: The primary outcome was 6-month continuous abstinence verified using a carbon monoxide breath test at 7-month follow-up. The noninferiority margin was set at 5% and the 1-sided significance threshold was set at .025. Results: Among 1452 participants who were randomized (mean [SD] age, 42.9 [12.7] years; 742 [51.1%] women), 1108 (76.3%) completed the trial. Verified 6-month continuous abstinence rates were 11.7% for the cytisine group and 13.3% for the varenicline group (risk difference, -1.62% [1-sided 97.5% CI, -5.02% to ∞]; P = .03 for noninferiority). Self-reported adverse events occurred less frequently in the cytisine group (997 events among 482 participants) compared with the varenicline group (1206 events among 510 participants) and the incident rate ratio was 0.88 (95% CI, 0.81 to 0.95; P = .002). Conclusions and Relevance: Among daily smokers willing to quit, cytisine treatment for 25 days, compared with varenicline treatment for 84 days, failed to demonstrate noninferiority regarding smoking cessation. Trial Registration: anzctr.org.au Identifier: ACTRN12616001654448.


Assuntos
Alcaloides/uso terapêutico , Agentes de Cessação do Hábito de Fumar/uso terapêutico , Abandono do Hábito de Fumar/métodos , Vareniclina/uso terapêutico , Adulto , Alcaloides/efeitos adversos , Azocinas/efeitos adversos , Azocinas/uso terapêutico , Sonhos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Quinolizinas/efeitos adversos , Quinolizinas/uso terapêutico , Agentes de Cessação do Hábito de Fumar/efeitos adversos , Resultado do Tratamento , Vareniclina/efeitos adversos
9.
Cells ; 10(2)2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671798

RESUMO

We investigated the role of aldosterone (ALDO) in the development of arterial thrombosis in streptozotocin-induced diabetic rats. To evaluate the effect of endogenous ALDO, the rats underwent adrenalectomy (ADX). ADX reduced the development of arterial thrombosis. A 1 h infusion of ALDO (30 µg/kg/h) enhanced thrombosis in adrenalectomized rats, while this effect was potentiated in diabetic rats. ALDO shortened bleeding time, increased plasma levels of tissue factor (TF) and plasminogen activator inhibitor, decreased plasma level of nitric oxide (NO) metabolites, and increased oxidative stress. Moreover, 2 h incubation of human umbilical vein endothelial cells (HUVECs) with ALDO (10-7 M) disrupted hemostatic balance in endothelial cells in normoglycemia (glucose 5.5 mM), and this effect was more pronounced in hyperglycemia (glucose 30 mM). We demonstrated that the acute ALDO infusion enhances arterial thrombosis in rats and hyperglycemia potentiates this prothrombotic effect. The mechanism of ALDO action was partially mediated by mineralocorticoid (MR) and glucocorticoid (GR) receptors and related to impact of the hormone on primary hemostasis, TF-dependent coagulation cascade, fibrinolysis, NO bioavailability, and oxidative stress balance. Our in vitro study confirmed that ALDO induces prothrombotic phenotype in the endothelium, particularly under hyperglycemic conditions.


Assuntos
Aldosterona/efeitos adversos , Aldosterona/uso terapêutico , Hiperglicemia/tratamento farmacológico , Hiperglicemia/etiologia , Animais , Diabetes Mellitus Experimental/complicações , Modelos Animais de Doenças , Ratos , Ratos Wistar , Trombose/etiologia , Trombose/fisiopatologia
10.
Toxins (Basel) ; 12(9)2020 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-32872484

RESUMO

Quinolizidine alkaloids exhibit various forms of biological activity. A lot of them were found in the Leguminosae family, including Laburnum and Genista. The aim of the study was the optimization of a chromatographic system for the analysis of cytisine and N-methylcytisine in various plant extracts as well as an investigation of the cytotoxic activities of selected alkaloids and plant extracts obtained from Laburnum anagyroides, Laburnum anagyroides L. quercifolium, Laburnum alpinum, Laburnum watereri, Genista germanica, and Genista tinctoria against various cancer cell lines. The determination of investigated compounds was performed by High Performance Liquid Chromatography with Diode Array Detection (HPLC-DAD), while High Performance Liquid Chromatography coupled with Quadrupole Time-of-Flight-Mass Spectrometry (HPLC-QTOF-MS) was applied for the qualitative analysis of plant extracts. The retention, separation selectivity, peaks shape, and systems efficiency obtained for cytisine and N-methylcytisine in different chromatographic systems were compared. The application of columns with alkylbonded and phenyl stationary phases led to a very weak retention of cytisine and N-methylcytisine, even when the mobile phases containing only 5% of organic modifiers were used. The strongest retention was observed when hydrophilic interaction chromatography (HILIC) or especially when ion exchange chromatography (IEC) were applied. The most optimal system in terms of alkaloid retention, peak shape, and system efficiency containing an strong cation exchange (SCX) stationary phase and a mobile phase consisted of 25% acetonitrile and formic buffer at pH 4.0 was applied for investigating alkaloids analysis in plant extracts. Cytotoxic properties of the investigated plant extracts as well as cytisine and N-methylcytisine were examined using human tongue squamous carcinoma cells (SCC-25), human pharyngeal squamous carcinoma cells (FaDu), human triple-negative breast adenocarcinoma cell line (MDA-MB-231), and human breast adenocarcinoma cell line (MCF-7). The highest cytotoxic activity against FaDu, MCF-7, and MDA-MB cancer cell lines was observed after applying the Genista germanica leaves extract. In contrast, the highest cytotoxic activity against SCC-25 cell line was obtained after treating with the seed extract of Laburnum watereri. The investigated plant extracts exhibit significant cytotoxicity against the tested human cancer cell lines and seem to be promising for further research on its anticancer activity.


Assuntos
Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Extratos Vegetais/isolamento & purificação , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Azocinas/isolamento & purificação , Azocinas/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Células MCF-7 , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Extratos Vegetais/farmacologia , Quinolizinas/isolamento & purificação , Quinolizinas/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
11.
Pharmaceutics ; 12(5)2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32456066

RESUMO

Third-generation poly(amidoamine) dendrimer (PAMAM) was modified by stepwise primary amine group amidation with d-glucoheptono-1,4-lactone. The physicochemical properties of the conjugates-size, ζ potential in lysosomal pH 5 and in neutral aqueous solutions, as well as intramolecular dynamics by differential scanning calorimetry-were determined. Internalization and toxicity of the conjugates against normal human fibroblasts BJ were monitored in vitro in order to select an appropriate carrier for a drug delivery system. It was found that initial glucoheptoamidation (up to 1/3 of amine groups of neat dendrimers available) resulted in increase of conjugate size and ζ potential. Native or low substituted dendrimer conjugates accumulated efficiently in fibroblast cells at nontoxic 1 µM concentration. Further substitution of dendrimer caused consistent decrease of size and ζ potential, cell accumulation, and toxicity. All dendrimers are amorphous at 36.6 °C as determined by differential scanning calorimetry (DSC). The optimized dendrimer, half-filled with glucoheptoamide substituents, was applied as carrier bearing two covalently attached cytisine molecules: a rigid and hydrophobic alkaloid. The conjugate with 2 cytisine and 16 glucoheptoamide substituents showed fast accumulation and no toxicity up to 200 µM concentration. The half-glucoheptoamidated PAMAM dendrimer was selected as a promising anticancer drug carrier for further applications.

12.
Neurotox Res ; 37(4): 1036-1046, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31792805

RESUMO

This study investigated the influence of sildenafil and methylene blue (MB), two modulators of the nitric oxide (NO)-cyclic guanosine-3',5'-monophosphate (cGMP) pathway on amnesic effects of two benzodiazepines (BZs) (diazepam (DZ) and flunitrazepam (FNZ)), in rodents-mice and rats. In the modified elevated plus maze (mEPM) and novel object recognition (NOR) tests, MB given ip at a dose of 5 mg/kg 5 min prior to DZ administration (0.25 or 1 mg/kg, sc) enhanced/induced memory impairment caused by DZ. When MB (2.5, 5, and 10 mg/kg) was applied 5 min prior to FNZ administration (0.05 and 0.1 mg/kg), an effect was opposite and memory impairment induced by FNZ was reduced. When sildenafil (2.5 and 5 mg/kg, ip) was applied 5 min prior to DZ, we observed a reduction of DZ-induced memory deficiency in the mEPM test. A similar effect of sildenafil was shown in the NOR test when the drug was applied at doses of 1.25, 2.5, and 5 mg/kg prior to DZ. In the mEPM test, sildenafil at abovementioned doses had no effects on FNZ-induced memory impairment. In turns, sildenafil administered at doses of 2.5 and 5 mg/kg increased the effect of FNZ on memory impairment in the NOR test. In conclusion, the NO-cGMP pathway is involved differentially into BZs-induced spatial and recognition memory impairments assessed using the NOR and mEPM tests. Modulators of the NO-cGMP pathway affect animal behavior in these tests in a different way depending on what benzodiazepine is applied.


Assuntos
GMP Cíclico/metabolismo , Diazepam/toxicidade , Flunitrazepam/toxicidade , Óxido Nítrico/metabolismo , Reconhecimento Psicológico/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Moduladores GABAérgicos/toxicidade , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Ratos , Ratos Wistar , Reconhecimento Psicológico/fisiologia , Roedores , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Memória Espacial/fisiologia
13.
Molecules ; 24(14)2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31315205

RESUMO

Background: Identification and quantitative determination of cytisine, especially in biological samples and pharmaceutical formulations, is still a difficult analytical task. Cytisine is an alkaloid with a small and very polar molecule. For this reason, it is very weakly retained on reversed phase (RP) stationary phases, such as commonly used alkyl-bonded phases. The very weak retention of cytisine causes it to be eluted together with the components of biological matrices. Objective: Comparison and evaluation of various chromatographic systems for analysis of cytisine in different matrices-serum, saliva and pharmaceutical formulation-by high performance liquid chromatography (HPLC) with diode array (DAD), fluorescence (FLD) and mass spectrometry (MS) detection. Methods: The analyses were performed using HPLC in reversed phase (RP), hydrophilic interaction liquid chromatography (HILIC) and ion exchange chromatography (IEC) modes. Different sample pre-treatment methods were tested: Protein precipitation (with acetone, methanol (MeOH) or acetonitrile (ACN), and solid phase extraction (SPE) using cartridges with octadecyl (C18), hydrophilic-lipophilic balanced copolymer (HLB) or strong cation exchange sorbents (Strata X-C). Conclusion: Significant differences were observed in retention parameters with a change of the used chromatographic system. The various properties of stationary phases resulted in differences in analyte retention, peaks' shape and systems' efficiency. The weakest retention was observed using RP systems; however, the use of the Polar RP phase can be an alternative for application in green chromatography. In the strongest retention was observed using a strong cation exchange (SCX) phase. The most optimal systems were chosen for the analysis of cytisine in the pharmaceutical preparation, serum and saliva after sample pre-treatment with the new SPE procedure. Due to the sensitivity, the use of HPLC-DAD or HPLC-FLD is the most optimal for drug analysis in pharmaceutical preparations, whereas HPLC-MS is suitable for analysis of cytisine in biological samples.


Assuntos
Alcaloides/análise , Preparações Farmacêuticas/química , Saliva/química , Soro/química , Azocinas/análise , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Fluorescência , Humanos , Interações Hidrofóbicas e Hidrofílicas , Espectrometria de Massas , Quinolizinas/análise
14.
Addiction ; 114(11): 1951-1969, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31240783

RESUMO

AIMS: To review cytisine's history of use, pre-clinical evidence, clinical pharmacokinetics, efficacy, adverse reactions (ARs) and safety for smoking cessation. METHODS: A synoptic review of the use of cytisine as a smoking cessation medication, mechanism of action, pharmacokinetics and safety. Relevant literature on data included in these sections were identified through a search of 11 databases with additional literature obtained from reports and monographs. Three databases (PubMed, EMBASE and www.elibrary.ru) were systematically searched for studies published from 2012 to August 2018 in any language to provide an updated meta-analysis of cytisine's efficacy and ARs for smoking cessation compared with placebo. We pooled the relative risks (RR) of abstinence in the efficacy analysis and RR of ARs, either reported by the authors or calculated from the reports. RESULTS: Cytisine has been in use since 1964 and is currently marketed in 18 countries. Systemic bioavailability from oral ingestion is high and clearance is primarily renal, with minimal or no metabolism. Brain uptake in animal models is moderate. The plasma half-life averages 4.8 hours. Eight studies were included for meta-analysis of efficacy. With heterogeneous results, the overall RR versus placebo of successful continuous abstinence at the longest follow-up was 1.74 [95% confidence interval (CI) = 1.38-2.19]. Nausea, vomiting, dyspepsia, upper abdominal pain and dry mouth that were mild or moderate were the most common ARs, with RR versus placebo 1.10 (95% CI = 0.95-1.28). The cost of cytisine in eastern and central Europe is several-fold less than that of other smoking cessation medications. CONCLUSIONS: Cytisine is a low-cost medication found to increase the likelihood of smoking cessation. The most frequently reported ARs of cytisine involve gastrointestinal symptoms that are mostly reported as either mild or moderate in severity.


Assuntos
Alcaloides/farmacologia , Alcaloides/uso terapêutico , Abandono do Hábito de Fumar/métodos , Tabagismo/tratamento farmacológico , Azocinas/farmacologia , Azocinas/uso terapêutico , Ensaios Clínicos como Assunto , Humanos , Quinolizinas/farmacologia , Quinolizinas/uso terapêutico
15.
Psychoneuroendocrinology ; 101: 27-34, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30408720

RESUMO

This study evaluated the effect of androsterone (AND), a metabolite of testosterone, on the ability of selected classical and novel antiepileptic drugs to prevent seizures caused by maximal electroshock (MES), which may serve as an experimental model of human generalized tonic-clonic seizures in mice. Single intraperitoneal (i.p.) administration of AND (80 mg kg-1) significantly raised the threshold for convulsions in the MES seizure threshold test. Lower doses of AND (5, 10, 20, and 40 mg kg-1) failed to change the threshold. AND at a subthreshold dose of 40 mg kg-1 significantly enhanced the protective activity of carbamazepine, gabapentin, and phenobarbital against MES-induced seizures decreasing their median effective doses (ED50) values ± SEM from 8.59 ± 0.76 to 6.05 ± 0.81 mg kg-1 (p = 0.0308) for carbamazepine, from 419.9 ± 120.6 to 111.5 ± 41.1 mg kg-1 (p = 0.0405) for gabapentin, and from 20.86 ± 1.64 to 10.0 ± 1.21 mg kg-1 (p = 0.0007) for phenobarbital. There were no significant changes in total brain concentrations of carbamazepine, gabapentin, and phenobarbital following AND administration. This suggests that the enhancing effects of AND on the protective activity of these antiepileptic drugs are not related to pharmacokinetic factors. A lower dose of AND (20 mg kg-1) had no effect on the protective activity of carbamazepine, gabapentin, and phenobarbital. AND administered at a dose of 40 mg kg-1 failed to change the anticonvulsant activity of lamotrigine, oxcarbazepine, phenytoin, topiramate, and valproate in the MES test. In the chimney test, AND given at a dose enhancing the protective activity of carbamazepine, gabapentin, and phenobarbital (which alone was without effect on motor performance of mice) did not affect impairment of motor coordination produced by the antiepileptics. Our findings recommend further preclinical and clinical research on AND in respect of its use as adjuvant therapy in the management of epilepsy in men with deficiency of androgens.


Assuntos
Androsterona/farmacologia , Anticonvulsivantes/metabolismo , Convulsões/fisiopatologia , Androgênios/metabolismo , Androsterona/metabolismo , Animais , Anticonvulsivantes/farmacologia , Aprendizagem da Esquiva/efeitos dos fármacos , Encéfalo/metabolismo , Carbamazepina , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Eletrochoque , Epilepsia/complicações , Gabapentina , Masculino , Camundongos , Fenobarbital , Desempenho Psicomotor/efeitos dos fármacos , Convulsões/metabolismo
16.
Addiction ; 114(5): 923-933, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30589984

RESUMO

BACKGROUND AND AIMS: Smoking cessation medications are effective, but often underutilized because of costs and side effects. Cytisine is a plant-based smoking cessation medication with more than 50 years of use in central and eastern Europe. While cytisine has been found to be well-tolerated and more effective than nicotine replacement therapy, direct comparisons with varenicline have not been conducted. This study evaluates the effectiveness, safety and cost-effectiveness of cytisine compared with varenicline. DESIGN: Two-arm, parallel group, randomized, non-inferiority trial, with allocation concealment and blinded outcome assessment. SETTING: Australian population-based study. PARTICIPANTS: Adult daily smokers (n = 1266) interested in quitting will be recruited through advertisements and Quitline telephone-based cessation support services. INTERVENTION AND COMPARATOR: Eligible participants will be randomized (1 : 1 ratio) to receive either cytisine capsules (25-day supply) or varenicline tablets (12-week supply), prescribed in accordance with the manufacturer's recommended dosing regimen. The medication will be mailed to each participant's nominated residential address. All participants will also be offered standard Quitline behavioural support (up to six 10-12-minute sessions). MEASUREMENTS: Assessments will be undertaken by telephone at baseline, 4 and 7 months post-randomization. Participants will also be contacted twice (2 and 4 weeks post-randomization) to ascertain adverse events, treatment adherence and smoking status. The primary outcome will be self-reported 6-month continuous abstinence from smoking, verified by carbon monoxide at 7-month follow-up. We will also evaluate the relative safety and cost-effectiveness of cytisine compared with varenicline. Secondary outcomes will include self-reported continuous and 7-day point prevalence abstinence and cigarette consumption at each follow-up interview. COMMENTS: If cytisine is as effective as varenicline, its lower cost and natural plant-based composition may make it an acceptable and affordable smoking cessation medication that could save millions of lives world-wide.


Assuntos
Alcaloides/economia , Alcaloides/uso terapêutico , Abandono do Hábito de Fumar/economia , Abandono do Hábito de Fumar/métodos , Vareniclina/economia , Vareniclina/uso terapêutico , Adulto , Alcaloides/efeitos adversos , Austrália , Azocinas/efeitos adversos , Azocinas/economia , Azocinas/uso terapêutico , Análise Custo-Benefício , Método Duplo-Cego , Estudos de Equivalência como Asunto , Feminino , Humanos , Masculino , Quinolizinas/efeitos adversos , Quinolizinas/economia , Quinolizinas/uso terapêutico , Resultado do Tratamento , Vareniclina/efeitos adversos
17.
Curr Drug Targets ; 19(16): 1968-1979, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29577853

RESUMO

Aldosterone, the main mineralocorticoid hormone, plays a crucial role in the regulation of electrolyte homeostasis and blood pressure. Although this role is undoubtedly important, it is not a hormonal action that attracts the most attention. Aldosterone seems to be very important as a local messenger in the pathology of cardiovascular diseases (CVD). In the last few years, the attention was focused on the correlation between raised aldosterone level and increased risk of cardiovascular events. It has been demonstrated that aldosterone contributes to fibrosis, inflammation, endothelial dysfunction, fibrinolytic disorders, and oxidative stress leading to CVD development and progression. It used to be thought that the effects of aldosterone are mediated via classic nuclear receptors - mineralocorticoid receptors (MRs). Now we know that the mechanism of aldosterone action in the cardiovascular system (CVS) is much more complex since experimental and clinical studies indicate that MR blockade may be not sufficient to abolish aldosterone-induced harmful effects in CVS. Thus, the involvement of some other than MR, receptors, and factors is suggested. Moreover, in addition to the generally known genomic action of aldosterone, which involves MR activation, the nongenomic pathways are postulated in the mode of hormone action. More and more attention is focused on the membrane-coupled receptors, which mediate the rapid effects of aldosterone and have been already confirmed in different cells and tissues of CVS. Therefore, this brief review summarizes recent findings about new sides of aldosterone action in CVS that could be potential targets for therapeutic intervention.


Assuntos
Aldosterona/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Sistema Cardiovascular/efeitos dos fármacos , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Sistema Cardiovascular/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Modelos Animais de Doenças , Eletrólitos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Biossíntese de Proteínas/efeitos dos fármacos , Receptores Adrenérgicos beta/metabolismo , Receptores de Angiotensina/metabolismo , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Glucocorticoides/antagonistas & inibidores , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismo , Transdução de Sinais/genética , Transcrição Gênica/efeitos dos fármacos
18.
Pharmacol Rep ; 70(1): 106-109, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29335158

RESUMO

BACKGROUND: Recent evidence reveals therapeutic potential for cannabinoids to reduce seizure frequency, severity and duration. Animal models are useful tools to determine the potential antiseizure or antiepileptic effects of cannabinoids. The objective of this study was evaluation of the effect of arvanil, olvanil, AM 1172 and LY 2183240, the compounds interacted with endocannabinoid and/or endovanilloid systems, on convulsions in the commonly used model of convulsions in mice. METHODS: Arvanil and olvanil were injected intraperitoneally (ip) 30min and AM 1172 and LY 2183240 were administered ip 60min before the maximal electroshock seizure threshold (MEST) test. The criterion for convulsant activity was tonic hindlimb extension. RESULTS: Arvanil, olvanil, AM 1172 and LY 2183240 dose-dependently increased the electroconvulsive threshold in mice. The TID20 (threshold increasing dose 20) values for arvanil, olvanil, AM 1172 and LY 2183240 were 0.9, 2.18, 2.48 and 3.56mgkg-1, respectively, and the TID50 (threshold increasing dose 50) values were 1.88, 6.45, 6.29 and 10.04mgkg-1, respectively. CONCLUSION: This study identified anticonvulsant effects of arvanil, olvanil, AM 1172 and LY 2183240. The order of the magnitude of the anticonvulsant effects of the examined compounds was following: arvanil>olvanil>AM 1172>LY 2183240.


Assuntos
Ácidos Araquidônicos/farmacologia , Benzamidas/farmacologia , Ondas Encefálicas/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Agonistas de Receptores de Canabinoides/farmacologia , Capsaicina/análogos & derivados , Eletrochoque , Compostos Heterocíclicos com 1 Anel/farmacologia , Receptor CB1 de Canabinoide/agonistas , Convulsões/prevenção & controle , Ureia/análogos & derivados , Animais , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Capsaicina/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Masculino , Camundongos , Receptor CB1 de Canabinoide/metabolismo , Convulsões/etiologia , Convulsões/metabolismo , Convulsões/fisiopatologia , Transdução de Sinais/efeitos dos fármacos , Ureia/farmacologia
19.
J Clin Endocrinol Metab ; 102(11): 3924-3927, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28973408

RESUMO

Context: Carney complex (CNC) is a rare multiple neoplasia syndrome involving cardiac, endocrine, neural, and cutaneous tumors and a variety of pigmented skin lesions. CNC can be inherited as an autosomal dominant trait, but in about one-third of patients, the disease is caused by de novo mutation in the PRKAR1A gene localized on chromosome 17q22-24. Most of the mutations include single base substitutions and small deletions/insertions not exceeding 15 base pairs. Recently, large germline PRKAR1A deletions have been described and may cause a more severe phenotype. Case Description: Herein, we report the cases of two siblings with CNC with a de novo large deletion of 107 kb at 17q24.2 associated with acromegaly in both and primary pigmented nodular adrenocortical disease, cardiac myxoma, and lethal metastatic melanotic schwannian tumor at the age of 27 years in one of them, supporting the hypothesis that large deletions of PRKAR1A lead to severe disease. Conclusions: To our knowledge, this is the first description of familial CNC in siblings in which neither parent carried the deletion in blood-derived DNA, suggesting that one of them had germ cell mosaicism for this deletion. Testing for large gene deletions should be obtained in all patients who meet the diagnostic criteria for CNC but do not have a PRKAR1A mutation by Sanger sequencing.


Assuntos
Complexo de Carney/genética , Complexo de Carney/patologia , Deleção de Genes , Irmãos , Acromegalia/genética , Acromegalia/patologia , Adenoma/genética , Adenoma/patologia , Adulto , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/genética , Evolução Fatal , Feminino , Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Adenoma Hipofisário Secretor de Hormônio do Crescimento/patologia , Humanos , Masculino , Mutação
20.
Psychopharmacology (Berl) ; 234(2): 281-291, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27778062

RESUMO

BACKGROUND: Cytisine (CYT) is a partial agonist of brain α4ß2 nicotinic acetylcholine receptors widely used in Central/Eastern Europe for smoking cessation. OBJECTIVES: This study evaluated the effect of CYT on the ability of classical and novel antiepileptic drugs to prevent seizures evoked by the 6-Hz test, a model of psychomotor seizures in mice thought as a model of drug-resistant seizures. RESULTS: CYT administered intraperitoneally (i.p.) in a dose of 2 mg kg-1 significantly inhibited the anticonvulsant activity of lacosamide, levetiracetam, and pregabalin, increasing their median effective doses 50 (ED50) values from 6.88 to 10.52 mg kg-1 (P < 0.05) for lacosamide, from 22.08 to 38.26 mg kg-1 (P < 0.05) for levetiracetam, and from 40.48 to 64.61 mg kg-1 (P < 0.01) for pregabalin, respectively. There were no significant changes in total brain concentrations of lacosamide, levetiracetam, and pregabalin following CYT i.p. administration. CYT administered in a dose of 2 mg kg-1 failed to change the protective action of clobazam, clonazepam, phenobarbital, tiagabine, and valproate in the 6-Hz test. Neither CYT (2 mg kg-1) alone nor its combination with the anticonvulsant drugs (at their ED50 values from the 6-Hz test) affected motor coordination; skeletal muscular strength and long-term memory, as determined in the chimney; and grip strength and passive avoidance tests, respectively. CONCLUSION: CYT-evoked alterations in the protection provided by some antiepileptic drugs against seizures can be of serious concern for epileptic smokers, who might demonstrate therapeutic failure to lacosamide, levetiracetam, and pregabalin, resulting in possible breakthrough seizure attacks.


Assuntos
Alcaloides/toxicidade , Anticonvulsivantes/uso terapêutico , Eletrochoque/efeitos adversos , Agonistas Nicotínicos/toxicidade , Convulsões/tratamento farmacológico , Animais , Anticonvulsivantes/farmacologia , Azocinas/toxicidade , Relação Dose-Resposta a Droga , Levetiracetam , Masculino , Memória de Longo Prazo/efeitos dos fármacos , Memória de Longo Prazo/fisiologia , Camundongos , Fenobarbital/antagonistas & inibidores , Fenobarbital/farmacologia , Fenobarbital/uso terapêutico , Piracetam/análogos & derivados , Piracetam/antagonistas & inibidores , Piracetam/farmacologia , Piracetam/uso terapêutico , Quinolizinas/toxicidade , Convulsões/etiologia , Convulsões/psicologia , Ácido Valproico/antagonistas & inibidores , Ácido Valproico/farmacologia , Ácido Valproico/uso terapêutico
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