Doctor of Philosophy / Department of Anatomy and Physiology / Johann F. Coetzee / Flunixin meglumine has been used as an antipyretic and anti-inflammatory since the 1980s. In 2013, a novel formulation was released in the European Union for topical administration and transdermal absorption. Approval for transdermal flunixin in cattle in the United States occurred in 2017, and included a label claim for the control of pain associated with infectious pododermatitis (foot rot). This new formulation allows for needle-less delivery of flunixin with minimal restraint and training required. In this dissertation, the pharmacokinetics of transdermal flunixin in Holstein calves at 2 months of age and adult lactating cows is described. In these pharmacokinetic studies, plasma flunixin concentrations were determined using high-pressure liquid chromatography coupled with mass spectroscopy. Pharmacokinetic modeling was completed using non-compartmental modeling methods using a commercially available computer program. Ex vivo prostaglandin E₂ (PGE₂) production using a whole blood model served as a biomarker for the anti-inflammatory effects of flunixin meglumine and suppression of cyclo-oxygenase enzyme-2. The concentrations of PGE₂ were determined using a commercially available enzyme-linked immunosorbent linked assay (ELISA) kit. The effects of age and pain on the pharmacokinetics of flunixin were investigated. Both influenced the pharmacokinetics and anti-inflammatory effects of flunixin. Cautery dehorning without local anesthetic was used in the calf model to generate pain. The pain associated with dehorning caused lower absorption of the transdermal flunixin and a longer terminal half-life. This longer half-life did result in lower PGE₂ concentrations at later time points. The influence of age was determined in the same group of Holstein calves at 2 months and 8 month of age. Age related effects included lower clearance, a longer half-life, and longer suppression of PGE₂ following intravenous injection. Following transdermal administration, older animals had a prolonged absorption leading to a longer half-life and apparent ‘flip-flop’ pharmacokinetics. Additionally, the suppression of PGE₂ was not observed in older calves following transdermal flunixin administration. The analgesic properties of transdermal flunixin were tested using three different pain models. Those pain models include cautery dehorning, surgical castration, and induced lameness. The reduction in plasma cortisol following transdermal administration was the most consistent finding in each model for pain. Infrared thermography (IRT) was used to assess either activation of the autonomic nervous system or local inflammation. Flunixin did not have any effects on substance P concentration in all three pain models. Gait analysis using a floor based pressure mat was used in the assessment of castration and lameness pain. Although there were no observed effects of flunixin in those studies, the use of this technology for pain assessment is promising. Future studies of transdermal flunixin to determine its utility as part of a multi-modal analgesic plan are still warranted. Specifically, the use a of a local anesthetic block at the time of cautery dehorning, as flunixin has minimal effects on pain, and its pharmacokinetics were altered by the painful stimulus. Timing of the dose relative to the painful procedure is also needed as flunixin is rapidly absorbed. Field studies in lame cattle are needed as there is a deficiency in the literature as only models of lameness induction have been reported.

Master of Science in Biomedical Sciences / Department of Clinical Sciences / Elizabeth G. Davis / The primary study objective was to compare the pharmacokinetics of p.o. terbinafine alone to p.o. terbinafine administered with p.o. cimetidine in healthy adult horses. The second objective was to assess the pharmacokinetics of terbinafine when administered per rectum in two different suspensions at 30 mg/kg to adult horses. Six healthy adult horses were included in this crossover study. Plasma terbinafine concentrations were quantified with liquid chromatography and mass spectrometry. The half-life (geometric mean) was 8.38 and 10.76 h, for p.o. alone and p.o. with cimetidine, respectively. The mean maximum plasma concentrations were 0.291 lg/mL at 1.54 h and 0.418 lg/mL at 1.28 h for p.o. alone and p.o. with cimetidine, respectively. Terbinafine with cimetidine had an average CMAX 44% higher and the relative F was 153% compared p.o. terbinafine alone but was not statistically different (P > 0.05). Terbinafine was infrequently detected when administered per rectum in two different suspensions (water or olive oil). Minor adverse effects included oral irritation, fever, and colic. All resolved spontaneously. More pharmacokinetic studies are indicated assessing drug–drug interactions and using multiple dosing intervals to improve our knowledge of effective oral dosing, the potential for drug accumulation, and systemic adverse effect of terbinafine in horses.

The investigations detailed in this dissertation have been conducted to address the paucity of pharmacokinetic information, in published literature, pertaining to cyclizine. The areas of investigation have included the selective quantitation of both cyclizine and its demethylated metabolite, norcyclizine in serum and urine, assessment of stability of both compounds in stored biological samples, dosage form analysis, dissolution rate testing of tablets, and bioavailability and pharmacokinetics following administration of an intravenous solution, and tablets to humans. High-performance liquid chromatography (HPLC) was used as the main analytical technique throughout these studies. An original HPLC method employing ultraviolet detection with a limit of quantitation of 5μg/ℓ was developed for the determination of cyclizine in serum and both cyclizine and norcyclizine in urine, Solid-phase extraction using extraction columns packed with reversed-phase C18 material, and followed by a simple phase-separation step proved successful for the accurate and precise isolation of the compounds. The validated method was applied to the analysis of serum and urine samples from a pilot study in which a single volunteer was administered 50mg of cyclizine hydrochloride. Several samples collected during the pilot study revealed the presence of both drug and metabolite in concentrations below the limit of detection. In order to improve the selectivity and sensitivity of the analytical method an HPLC method with electrochemical detection operating in the "oxidative-screen" mode was developed. The solid-phase extraction procedure was modified slightly and the method found to be precise, accurate, selective and highly sensitive with a limit of quantitation of Iμg/g/l for both cyclizine and norcyclizine in both serum and urine. This method was applied to the determination of both compounds after intravenous and oral administration of cyclizine to humans. HPLC with electrochemical detection was used for the analysis of samples collected during dissolution studies on the batch of tablets used for pharmacokinetic studies. In addition, this method was used to assess content uniformity of the tablets and of samples from the batch of intravenous ampoules of cyclizine lactate. Dissolution studies showed that all tablets tested passed the compendial specifications for cyclizine. Content uniformity assessment revealed that within-batch uniformity existed for both the tablets and ampoules and, therefore, variations in pharmacokinetic parameters for the drug would more than likely be as a result of inter- and intra-individual variability within the subject population. Pharmacokinetic information for cyclizine was obtained following administration of an intravenous bolus dose of cyclizine lactate as a solution, oral administration of cyclizine hydrochloride as a single dose of 50mg and as fixed multiple doses of 50mg every 8 hours for five days. Further information was acquired following administration of single doses of 100mg and 150mg cyclizine hydrochloride. Data collected from these studies were evaluated using both compartmental and non-compartmental techniques. Cyclizine was rapidly absorbed following oral administration with mean kₐ = 1.54 hr⁻¹ and was found to have an absolute bioavailability (F) of 0.47. The presence of norcyclizine in serum following oral and not intravenous dosing suggests cyclizine is susceptible to "first-pass" metabolism in either the gut wall or the I iver. Mean ClTOT determined following the intravenous dose was 0.865 ℓ/hr/kg. The mean ClTOT of 0.823 ℓ/hr/kg calculated following oral dosing, using a unique value of F for each subject compared favourahly with that obtained following intravenous dosing. Renal clearance of cyclizine is negligihle indicating that non-renal routes of elimination account for the majority of removal of cyclizine form the body. Cyclizine is extensively distributed and the mean Vz following an intravenous dose was 16.70 ℓ/kg. This value is lower than that calculated from all oral studies from which the mean Vz was determined to be 25.74 ℓ/kg. Cyclizine is eliminated slowly with a mean elimination t½ = 20.11 hours. Cyclizine dose not appear to follow dosedependent kinetics and therefore, inability to predict steady state levels are more than likely due to accumulation as a result of frequent dosing rather than saturation of elimination mechanisms. Modelling of intravenous data to one-compartment (lBCM), two-compartment (2BCM) and threecompartment models indicated that the pharmacokinetics of cyclizine can be adequately described by a 3BCM. The drug is rapidly distributed into a "shallow" peripheral compartment (α = 9.44 hr⁻¹ , and k₂₁ = 2.09 hr⁻¹ ), and slowly distributed to the "deep" peripheral compartment (β = 0.451 hr⁻¹ and k₃₁ = 0.120 hr⁻¹ ). Modelling of all oral data indicated that a 2BCM best described the pharmacokinetics of the drug, however, distribution to the peripheral compartment is not as rapid as to the "shallow" peripheral compartment following the intravenous dose. Mean distribution parameters were α = 0.64 hr⁻¹1 and, k₂₁ = 0.39 hr⁻¹. Mean CITOT following intravenous dosing of 0.70 ℓ/hr/kg was similar to the mean CIToT of 0.73 ℓ/hr/kg determined after oral dosing. The mean distribution volume at steady state determined following intravenous dosing (17.78 ℓ/kg) was lower than that obtained from the oral studies (25.52 ℓ/kg). The mean terminal elimination half-lives calculated for cyclizine following fitting of intravenous and oral data was 25.09 hours. In general, mean pharmacokinetic parameters calculated following titting of data to a 2BCM after oral administration correlate closely with those calculated using non-compartmental techniques. However, the pharmacokinetics following intravenous dosing are better described by a 3BCM and a close correlation between parameters estimated using noncompartmental techniques and compartmental techniques is evident when a 3BCM model is used.

Objetivos: O objetivo deste estudo foi avaliar a influência do Diabetes Mellitus do tipo 2 na farmacocinética da glimepirida em ratos Wistar e descrever o perfil através de modelo farmacocinética populacional (popPK). Metodologia: Os experimentos com animais foram aprovados pelo CEUA/UFRGS (protocolo #27892). O diabetes foi induzido com administração intraperitoneal de 100 mg/kg de nicotinamida, 15 minutos antes da administração intravenosa de 65 mg/kg de STZ. Os animais com nível de glicemia > 250 mg/dL foram considerados diabéticos. A glimepirida foi administrada na dose de 5 mg/kg via i.v. nos animais sadios (n = 11) e diabéticos (n = 9) e quantificada por CLAE-UV. A ligação às proteínas plasmáticas foi determinada por método de ultracentrifugação (Centrifree®). A análise farmacocinética não compartimental (software Phoenix®) foi realizada, assim como a modelagem farmacocinética populacional (software Monolix ®). Resultados e Discussão: A metodologia analítica para quantificação da glimepirida em plasma foi desenvolvida e validada, seguindo os critérios do FDA, apresentou sensibilidade, exatidão e precisão. O modelo de indução da diabetes produziu glicemia > 250 mg/dL. A ligação às proteínas plasmáticas não foi afetada pela doença (LPPSaudáveis = 99,3 ± 0,09%, LPPDiabéticos = 99,13 ± 0,075%, p > 0,05). O modelo farmacocinético populacional estrutural de 2 compartimentos com eliminação de primeira-ordem com covariável categórica (diabetes), foi usado para descrever os perfis plasmáticos de concentração-tempo da glimepirida após administração intravenosa na dose de 5 mg/kg a ratos saudáveis e diabéticos. O CL e a ASC0-inf dos animais diabéticos foram estatisticamente diferentes dos animais saudáveis, CLpop Saudáveis= 0,066 L/h para CLpop diabéticos = 0,024 L/h e ASCpop saudáveis = 19,24 μg/mL.h para ASCpop diabéticos = 59,64 μg.h/mL, indicando que a eliminação foi alterada nos animais diabéticos induzidos STZ. Conclusões: A modela gempossibilitou identificação do parâmetro que atribuiu variabilidade entre os grupos. Desta forma, a variabilidade interindividual foi quantificada e incluída no modelo. O modelo popPK final, nos permitiu elucidar os fatores que afetam a farmacocinética da glimepirida e prever mudanças na exposição em uma população específica. / Objective: The aim of this study was to evaluate the influence of diabetes mellitus type 2 on the pharmacokinetics of glimepiride in rats and describe the profile in population pharmacokinetic model (popPK). Methods: The experiments with animals were approved by CEUA/UFRGS (protocol number). The diabetes was induced by intraperitoneal administration of NA (100 mg/kg) dissolved in saline 15 min before an intravenous administration of 65 mg/kg STZ in citrate buffer (pH 4.5) to overnight fasted rats. Animals with blood glucose level> 250 mg/dL were considered diabetic. After administered of glimepiride at a dose of 5 mg/kg i.v. bolus in healthy (n = 11) and diabetic animals (n = 9). Method HPLC-UV developed and validated quantified plasma concentrations. The plasma protein binding was determined by method ultracentrifugation (Centrifree®). Noncompartmental analysis of pharmacokinetic in Phoenix® software was performed, as well as the model pharmacokinetic population using Monolix®. Performed by Student's t-test for SigmaStat® software. Results and Discussion: The HPLC-UV method for quantification of glimepiride in plasma was developed and validated following requirements by FDA showing sensitivity, accuracy and precision. Induced diabetes model produced glucose> 250 mg / dL. The plasma protein binding was not affect by the disease (LPPSaudáveis = 99.3 ± 0.09%, LPPDiabéticos = 99.13 ± 0.075%, p> 0.05). The model pharmacokinetic population 2 compartments with eliminating first-order with categorical covariates diabetic was used to describe the plasma profile concentration-time glimepiride. The CL and AUC 0-inf of diabetic animals were significantly different. In healthy animals was Clpop Healthy = 0.066 L/h for diabetics Clpop = 0.024 L/h and healthy ASCpop = 19.24 g/mL.h ASCpop for diabetics = 59.64 g/mL.h, indicating that elimination was decreased in induced diabetic rats STZ. Conclusions: popPk enabled identification of the parameter assigned variability between the groups. Thus, the inter subject variability was measured and included in the model. The PBPK final model, allowed us to elucidate the factors that affect the pharmacokinetics of glimepiride and predict changes in exposure in a specific population.

Made available in DSpace on 2016-02-05T18:29:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-10-01. Added 1 bitstream(s) on 2016-02-05T18:33:20Z : No. of bitstreams: 1 000856417_20170730.pdf: 439965 bytes, checksum: 3270faac0cbd41571606afcec1c09a50 (MD5) Bitstreams deleted on 2017-08-07T14:09:11Z: 000856417_20170730.pdf,. Added 1 bitstream(s) on 2017-08-07T14:10:15Z : No. of bitstreams: 1 000856417.pdf: 3202526 bytes, checksum: 92cc9b27f04cf1ddd8e29425008ab955 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Instituto Nacional de Ciência e Tecnologia para inovação farmacêutica (INCT-if ) / A anemia falciforme é um distúrbio monogênico, cujas complicações resultam em um quadro debilitante, doloroso e fatal para os portadores. O planejamento, síntese e avaliação de novos compostos são imprescindíveis para renovar as esperanças daqueles acometidos por essa doença e os estudos de farmacocinética, relação PK/PD e de segurança são parte indispensável da continuidade de desenvolvimento de novos candidatos. O LAPDESF-SCD03 é uma nova molécula candidata a fármaco que foi planejada para o tratamento sintomático dessa doença e demonstrou resultados promissores. Neste trabalho desenvolvemos os estudos de farmacocinética pré-clínica e de avaliação da atividade inibitória da produção de TNF-α em ratos Wistar, e as análises foram realizadas por cromatografia líquida de ultra eficiência e ensaio imunoenzimático, respectivamente. Os estudos em busca de metabólitos foram conduzidos em hepatócitos e analisados por cromatografia líquida acoplada à espectrometria de massas de alta resolução. Nos parâmetros farmacocinéticos observados para o LAPDESF-SCD03 destaca-se a meia-vida curta (4,7 minutos) e o clearance elevado (172,5 mL/min.kg) para administração IV. Na administração oral o MRT foi 10 vezes maior que na administração IV com meia-vida de eliminação de 30 minutos. No estudo de relação PK/PD, foi observada redução dos níveis de TNF-α tanto pela via intravenosa, quanto pela via oral. No estudo de metabolismo, tanto na presença dos hepatócitos funcionais quanto na incubação com os hepatócitos não funcionais, foi observada a existência de um metabólito formado por hidrólise na subunidade ftalimídica, que de acordo com estudos previamente publicados com a talidomida e seus metabólitos, pode resultar em atividade inibitória da produção de TNF-α. Em conclusão, o fármaco mostrou atividade e teve sua farmacocinética... / Sickle cell disease is a severe monogenic disorder, whose complications include the increase in the susceptibility to infections, acute splenic sequestration, aplastic crisis, acute thoracic syndrome, vaso-occlusive crisis, cerebrovascular disease, bone disease, priapism and leg ulcerations. The design, synthesis and evaluation of new compounds are necessary in order to renew the hopefulness of those affected by this disease, and the preclinical pharmacokinetic study, PK/PD study, metabolism study and safety evaluations, are an indispensable part of the development of these candidates as LAPDESF-SCD03. The preclinical pharmacokinetic and the TNF-α inhibition evaluation have been done using ultra performance liquid chromatography and immunoassay, respectively. The metabolite study has been made using Wistar rat hepatocytes and analyzed liquid chromatography coupled to high resolution mass spectrometry. The main results in the pharmacokinetic parameters were the short half-life (4.7 minutos) and the high clearance (172,5 mL/min.kg). In the oral administration, the MRT was ten-fold higher than the observed one in the iv administration, while the half-life was 30 minutes. In the PK/PD study, it was observed TNF-α reduction by both routes of administration, intravenous and oral. The metabolism study has addressed the formation of open ring metabolite, even though in the absence of the functional cells. Aftermath, the drug has shown activity and its pharmacokinetic was achieved, including the identification of a probable metabolite, which maybe can be pharmacologically active.

Made available in DSpace on 2014-06-11T19:28:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-05-02Bitstream added on 2014-06-13T20:36:54Z : No. of bitstreams: 1 assumpcao_jucv_me_arafcf.pdf: 678214 bytes, checksum: 9acfe9078c5e33e1edcaa979ba032dca (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / Neste estudo investigou-se o perfil farmacocinético da DOX administrada na forma de microemulsão lipídica, em dose única i.v (6 mg/kg), a ratos Wistar (n=12; 250 g) e comparou-se ao perfil farmacocinético da doxorrubicina administrada na forma de cloridrato em solução aquosa. Ainda, avaliou-se a atividade da CKMb nos dois grupos de animais antes e após a administração das formulações com o objetivo de evidenciar a cardiotoxicidade do produto. Para a avaliação do perfil farmacocinético foram colhidas amostras seriadas de sangue (0 – 16 h) através de cânulas previamente implantadas na veia femoral, e para a avaliação da atividade de CKMb foram colhidas amostras de sangue nos tempos zero, 1 h e 12 h após a administração das formulações. Para a determinação da doxorrubicina em amostras de sangue e nas formulações, desenvolveu- se e validou-se um método analítico por HPLC com detecção por fluorescência (exc= 480 nm; em= 560 nm), empregando-se coluna Xterra (C18, 5 µm, 3,9 x 150 mm) e fase móvel composta por 25% de acetonitrila e 75% de água na presença de ácido fórmico (0,1%) e de solução de amônia 25% (0,1%), pH 3,0 , com fluxo de 0,8 mL/min, em modo gradiente. Para as determinações da atividade da CKMb utilizou-se o kit labtest. O método analítico desenvolvido demonstrou limites de confiança adequados para a sua aplicação na determinação da DOX em formulações e em amostras de plasma para a avaliação do seu perfil farmacocinético. Os parâmetros farmacocinéticos que apresentaram diferenças estatisticamente significativas (p<0,05, Mann-Whitney) entre a microemulsão e solução aquosa, apresentados como média (IC 95), foram respectivamente: Vd (L/kg) = 38,23 (24,94 – 51,50) vs 68,85 (55,69 – 82,00); tss (h) = 45,33 ( 39,45 – 58,20) vs 33,23 ( 27,7 – 38,75); β(h-1 )= 0,0014 (0,00072 – 0,00208) vs 0,00078... / The present study investigated the DOX pharmacokinetic profile when administered as a lipid microemulsion in a single dose (6 mg/kg, IV) to Wistar rats (n=12; 250g) and compared it to the pharmacokinetic profile of doxorubicin administered as hydrochloride in aqueous solution. With the purpose of demonstrating the cardiotoxicity of the product it also evaluated the CKMB activity in both animal groups before and after administration of the formulations. Serial blood samples were obtained (0 – 16h) through cannulas previously implanted into the femoral vein to evaluate the pharmacokinetic profile. To evaluate the CKMB activity, blood samples were collected after the formulation was administered at times zero, 1h and 12h. An analytical method by HPLC with fluorescence detection (exc= 480 nm; em= 560 nm) was developed and validated for the determination of doxorubicin in blood samples and in the formulations. The column used as stationary phase was Xterra  (C18, 5 µm, 3.9 x 150 mm) and the mobile phase was composed of 25% of acetonitrile and 75% of water in presence of formic acid (0.1%) and ammonia solution 25% (0.1%), pH 3.0 at a flow rate of 0.8 mL/min, gradient mode. The developed method demonstrated appropriate safety limits to its use in determining doxorubicin in formulations and in plasma samples, and therefore to evaluate the DOX pharmacokinetic profile. For the determination of CKMB activity it was used the Labtest. The pharmacokinetic parameters that showed statistically significant differences (p<0.05, Mann-Whitney) between the microemulsion and the aqueous solution, presented as medians (IC 95), were respectively: Vd (L/kg) = 38.23 (24.94 – 51.50) vs 68.85 (55.69 – 82.00); tss (h) = 45.33 (39.45 – 58.20) vs 33.23 ( 27.70 – 38.75); β(h-1 )= 0.0014 (0.00072 – 0.00208) vs 0.00078 ( 0.0004386 – 0.001076) and t1/2 (h) = 9.24 (5.31 – 13.17) vs 16.51 ... (Complete abstract click electronic access below)

Orientador: Natalia Valadares de Moraes / Banca: Jonas Augusto Rizzato Paschoal / Helen Mariana Baldan Cimatti / Resumo: A exposição ocupacional a agentes químicos é potencialmente capaz de modificar a disposição cinética ou o metabolismo de fármacos, principalmente em função da indução ou inibição de enzimas do sistema citocromo P450. Entretanto, estudos que mostram o efeito da exposição ocupacional a agentes químicos na atividade de transportadores de fármacos são escassos. O tolueno está presente no ambiente de trabalho principalmente na forma de vapor. Neste ambiente, o solvente é absorvido principalmente por inalação. O objetivo do estudo é avaliar a influência da exposição inalatória ao tolueno na atividade in vivo do polipeptídeo transportador de ânions orgânicos da família Oatp em ratos, empregando como fármaco marcador a pravastatina. Ratos machos Wistar (n=6 por tempo de coleta, por grupo) foram expostos ao tolueno (85 mg/m3) por inalação ou ao ar em câmara de exposição apenas pelo nariz por 6 horas/dia, 5 dias/semana, 4 semanas. Ao final do período de exposição, os animais receberam dose única de pravastatina (20 mg/kg) por via oral. Amostras seriadas de sangue foram coletadas até 8 horas após a administração de pravastatina. As concentrações plasmáticas do fármaco foram avaliadas por cromatografia líquida de alta eficiência com detecção por espectrometria de massas (LC-MS). O método de análise da pravastatina por LC-MS mostrou detectabilidade, precisão e exatidão compatíveis com a aplicação em estudos de disposição cinética após dose única em ratos. As áreas sob as curvas de concen... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Occupational exposure to chemical agents is potentially able to modify the kinetic disposition of drug metabolism, mainly due to the induction or inibition of cytochrome P450 enzymes. However, studies investigating the influence of occupational exposure to chemicals on the variability in drug response are rare. Toluene is present in the working environment particularly in vapor form. In this environment, the toluene is mainly absorbed by inhalation. Considering that, the aim of this study was evaluate the influence of inhalation to toluene in the in vivo activity of the polypeptide transporter organic anion (Oatp) family transporters in rats, using pravastatin as a probe drug. Male Wistar rats (n=6, for each sampling time) were exposed to toluene (85 mg / m3) by inhalation or air in a nose only exposure system for 6 hours/day, 5 days/week, during 4 weeks. After 4 weeks of exposure, animals received a single dose of pravastatin (20 mg/kg) orally. Serial blood samples were collected up to 8 hours after administration of pravastatin. Plasma concentrations of pravastatin were measured by high-performance liquid chromatography with detection by mass spectrometry (LC-MS). The analysis method of pravastatin by LC-MS showed detectability, precision and accuracy compatible with the application in kinetic disposition studies after single doses in rats. The areas under the plasma concentration versus time (AUC) were calculated by zero to the infinity by the Gauss-Laguerre Quadrature. Th... (Complete abstract click electronic access below) / Mestre

Orientador : Rosângela Gonçalves Peccinini / Banca: Regina Helena Costa Queiroz / Banca: Rafael Victorio Carvalho Guido / Banca: Vera Lúcia Lanchote / Banca: Chung Man Chin / Resumo: A anemia falciforme é um distúrbio monogênico, cujas complicações resultam em um quadro debilitante, doloroso e fatal para os portadores. O planejamento, síntese e avaliação de novos compostos são imprescindíveis para renovar as esperanças daqueles acometidos por essa doença e os estudos de farmacocinética, relação PK/PD e de segurança são parte indispensável da continuidade de desenvolvimento de novos candidatos. O LAPDESF-SCD03 é uma nova molécula candidata a fármaco que foi planejada para o tratamento sintomático dessa doença e demonstrou resultados promissores. Neste trabalho desenvolvemos os estudos de farmacocinética pré-clínica e de avaliação da atividade inibitória da produção de TNF-α em ratos Wistar, e as análises foram realizadas por cromatografia líquida de ultra eficiência e ensaio imunoenzimático, respectivamente. Os estudos em busca de metabólitos foram conduzidos em hepatócitos e analisados por cromatografia líquida acoplada à espectrometria de massas de alta resolução. Nos parâmetros farmacocinéticos observados para o LAPDESF-SCD03 destaca-se a meia-vida curta (4,7 minutos) e o clearance elevado (172,5 mL/min.kg) para administração IV. Na administração oral o MRT foi 10 vezes maior que na administração IV com meia-vida de eliminação de 30 minutos. No estudo de relação PK/PD, foi observada redução dos níveis de TNF-α tanto pela via intravenosa, quanto pela via oral. No estudo de metabolismo, tanto na presença dos hepatócitos funcionais quanto na incubação com os hepatócitos não funcionais, foi observada a existência de um metabólito formado por hidrólise na subunidade ftalimídica, que de acordo com estudos previamente publicados com a talidomida e seus metabólitos, pode resultar em atividade inibitória da produção de TNF-α. Em conclusão, o fármaco mostrou atividade e teve sua farmacocinética... / Abstract: Sickle cell disease is a severe monogenic disorder, whose complications include the increase in the susceptibility to infections, acute splenic sequestration, aplastic crisis, acute thoracic syndrome, vaso-occlusive crisis, cerebrovascular disease, bone disease, priapism and leg ulcerations. The design, synthesis and evaluation of new compounds are necessary in order to renew the hopefulness of those affected by this disease, and the preclinical pharmacokinetic study, PK/PD study, metabolism study and safety evaluations, are an indispensable part of the development of these candidates as LAPDESF-SCD03. The preclinical pharmacokinetic and the TNF-α inhibition evaluation have been done using ultra performance liquid chromatography and immunoassay, respectively. The metabolite study has been made using Wistar rat hepatocytes and analyzed liquid chromatography coupled to high resolution mass spectrometry. The main results in the pharmacokinetic parameters were the short half-life (4.7 minutos) and the high clearance (172,5 mL/min.kg). In the oral administration, the MRT was ten-fold higher than the observed one in the iv administration, while the half-life was 30 minutes. In the PK/PD study, it was observed TNF-α reduction by both routes of administration, intravenous and oral. The metabolism study has addressed the formation of open ring metabolite, even though in the absence of the functional cells. Aftermath, the drug has shown activity and its pharmacokinetic was achieved, including the identification of a probable metabolite, which maybe can be pharmacologically active. / Doutor

Objetivos: O objetivo deste estudo foi avaliar a influência do Diabetes Mellitus do tipo 2 na farmacocinética da glimepirida em ratos Wistar e descrever o perfil através de modelo farmacocinética populacional (popPK). Metodologia: Os experimentos com animais foram aprovados pelo CEUA/UFRGS (protocolo #27892). O diabetes foi induzido com administração intraperitoneal de 100 mg/kg de nicotinamida, 15 minutos antes da administração intravenosa de 65 mg/kg de STZ. Os animais com nível de glicemia > 250 mg/dL foram considerados diabéticos. A glimepirida foi administrada na dose de 5 mg/kg via i.v. nos animais sadios (n = 11) e diabéticos (n = 9) e quantificada por CLAE-UV. A ligação às proteínas plasmáticas foi determinada por método de ultracentrifugação (Centrifree®). A análise farmacocinética não compartimental (software Phoenix®) foi realizada, assim como a modelagem farmacocinética populacional (software Monolix ®). Resultados e Discussão: A metodologia analítica para quantificação da glimepirida em plasma foi desenvolvida e validada, seguindo os critérios do FDA, apresentou sensibilidade, exatidão e precisão. O modelo de indução da diabetes produziu glicemia > 250 mg/dL. A ligação às proteínas plasmáticas não foi afetada pela doença (LPPSaudáveis = 99,3 ± 0,09%, LPPDiabéticos = 99,13 ± 0,075%, p > 0,05). O modelo farmacocinético populacional estrutural de 2 compartimentos com eliminação de primeira-ordem com covariável categórica (diabetes), foi usado para descrever os perfis plasmáticos de concentração-tempo da glimepirida após administração intravenosa na dose de 5 mg/kg a ratos saudáveis e diabéticos. O CL e a ASC0-inf dos animais diabéticos foram estatisticamente diferentes dos animais saudáveis, CLpop Saudáveis= 0,066 L/h para CLpop diabéticos = 0,024 L/h e ASCpop saudáveis = 19,24 μg/mL.h para ASCpop diabéticos = 59,64 μg.h/mL, indicando que a eliminação foi alterada nos animais diabéticos induzidos STZ. Conclusões: A modela gempossibilitou identificação do parâmetro que atribuiu variabilidade entre os grupos. Desta forma, a variabilidade interindividual foi quantificada e incluída no modelo. O modelo popPK final, nos permitiu elucidar os fatores que afetam a farmacocinética da glimepirida e prever mudanças na exposição em uma população específica. / Objective: The aim of this study was to evaluate the influence of diabetes mellitus type 2 on the pharmacokinetics of glimepiride in rats and describe the profile in population pharmacokinetic model (popPK). Methods: The experiments with animals were approved by CEUA/UFRGS (protocol number). The diabetes was induced by intraperitoneal administration of NA (100 mg/kg) dissolved in saline 15 min before an intravenous administration of 65 mg/kg STZ in citrate buffer (pH 4.5) to overnight fasted rats. Animals with blood glucose level> 250 mg/dL were considered diabetic. After administered of glimepiride at a dose of 5 mg/kg i.v. bolus in healthy (n = 11) and diabetic animals (n = 9). Method HPLC-UV developed and validated quantified plasma concentrations. The plasma protein binding was determined by method ultracentrifugation (Centrifree®). Noncompartmental analysis of pharmacokinetic in Phoenix® software was performed, as well as the model pharmacokinetic population using Monolix®. Performed by Student's t-test for SigmaStat® software. Results and Discussion: The HPLC-UV method for quantification of glimepiride in plasma was developed and validated following requirements by FDA showing sensitivity, accuracy and precision. Induced diabetes model produced glucose> 250 mg / dL. The plasma protein binding was not affect by the disease (LPPSaudáveis = 99.3 ± 0.09%, LPPDiabéticos = 99.13 ± 0.075%, p> 0.05). The model pharmacokinetic population 2 compartments with eliminating first-order with categorical covariates diabetic was used to describe the plasma profile concentration-time glimepiride. The CL and AUC 0-inf of diabetic animals were significantly different. In healthy animals was Clpop Healthy = 0.066 L/h for diabetics Clpop = 0.024 L/h and healthy ASCpop = 19.24 g/mL.h ASCpop for diabetics = 59.64 g/mL.h, indicating that elimination was decreased in induced diabetic rats STZ. Conclusions: popPk enabled identification of the parameter assigned variability between the groups. Thus, the inter subject variability was measured and included in the model. The PBPK final model, allowed us to elucidate the factors that affect the pharmacokinetics of glimepiride and predict changes in exposure in a specific population.

Orientador: Francisco Carlos Groppo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-13T23:25:13Z (GMT). No. of bitstreams: 1 Bergamaschi_CristianedeCassia_D.pdf: 2052308 bytes, checksum: b1179c44a980353d8216c7fb92cdc21a (MD5) Previous issue date: 2009 / Resumo: Foram objetivos deste estudo: 1) comparar o efeito das formulações (gel e comprimido) de metronidazol (Mtz) sobre o debridamento periodontal (DP) em pacientes fumantes; 2) comparar as concentrações plasmáticas (CP) e salivares (CS) destas formulações; 3) determinar a farmacocinética do Mtz em comprimido; e 4) avaliar o efeito do fumo na biodisponibilidade do Mtz comprimido. Cada objetivo constituiu um capítulo do estudo. Capítulo 1: 30 fumantes com periodontite crônica foram aleatoriamente divididos em 3 grupos: DP associado com 3 g de gel placebo; DP associado com aplicação tópica diária de 3 g de gel de benzoato de Mtz e; DP associado com dose oral única diária de 750 mg de Mtz (Flagyl®). Foram avaliados: Índice de Placa (IP), Índice de Sangramento Gengival (ISG), Profundidade à Sondagem (PS) e Nível Clínico de Inserção relativo (NIC); nos tempos: pré-operatório, baseline, e após 30, 90 e 180 dias do tratamento periodontal. Nenhuma diferença significante foi observada entre os grupos para todos os parâmetros e tempos avaliados. Houve uma significante redução no ISG, PS e NIC em todos os tempos comparados ao baseline (p<0,05). Capítulo 2: 13 voluntários sadios receberam aleatoriamente dose oral única de 750mg de Mtz ou 3g de gel Mtz (15%). Amostras de plasma e saliva foram colhidas em diferentes tempos após administração. Cromatografia Líquida de Alta Eficiência (CLAE) foi usada para quantificar as CP e CS do Mtz. Os parâmetros farmacocinéticos concentração máxima (Cmax), área sob a curva de zero ao infinito (ASC0-inf), área sob a curva de zero a t (ASC0-t), volume de distribuição (VD) e clearence renal (CL) foram determinados. As CP do Mtz foram maiores que as CS nos períodos de 6 a 24 horas para o comprimido (p<0,05). Os parâmetros ASC0-inf e ASC0-t foram maiores no plasma que na saliva (p<0,05). As concentrações plasmáticas e salivares foram similares para a formulação gel (p>0,05). Capítulo 3: 13 fumantes (F) e 13 nãofumantes (NF) receberam dose oral única de 750mg Mtz. Amostras de plasma e saliva foram colhidas em diferentes tempos após administração. A CLAE foi usada para quantificar as CP e CS do Mtz. Os parâmetros farmacocinéticos AUC, Cmax, Tmax, VD e CL foram determinados. Foram observadas redução significante nas concentrações plasmáticas no grupo F comparada ao NF em 1, 1,5 e 2 horas após a administração e na Cmax plasmática (p<0,05). Nenhuma diferença foi observada entre os grupos na concentração e nos parâmetros farmacocinéticos do Mtz em saliva (p>0,05). Conclusão geral: 1) Não houve vantagem clínica no uso do Mtz associado ao DP; 2) A formulação em gel produziu igual disponibilidade de Mtz no plasma e na saliva; 3) Alguns dos parâmetros farmacocinéticos do Mtz foram maiores no plasma que na saliva para o comprimido; 4) O fumo interferiu apenas na biodisponibilidade plasmática do Mtz. / Abstract: The aim of this study were 1) to compare the effect of metronidazole (Mtz) gel and tablet on debridement periodontal (DP) in smokers; 2) to compare Mtz gel and tablet concentrations in both blood plasma and saliva; 3) to determine the pharmacokinetic profile of Mtz tablet; and 4) to verify the effect of cigarette smoking on bioavailability of Mtz tablet. This study was divided in three chapters. Chapter 1: 30 patients smokers with chronic periodontitis were randomly assigned into 3 groups: PD combined with 3 g placebo gel; PD combined with daily topical application of 3 g Mtz benzoate gel (15%); and PD combined with a daily single dose of 750 mg Mtz (Flagyl®). Clinical parameters evaluated were visible plaque index (VPI), gingival bleeding index (GBI), probing pocket depth (PPD) and relative attachment level (RAL) which were assessed preoperatively, baseline, and after 1, 3 and 6 months after PD. No significant difference was observed among the groups, considering all parameters tested (p>0.05). In all groups was observed a significant reduction in GBI, PPD and RAL, at all times compared to baseline (p<0.05). Chapter 2: 13 volunteers randomly received 750 mg single oral dose FLagyl® and 3 g Mtz benzoate gel (15%). Blood and saliva samples were collected in different times after gel application and oral administration of Mtz. High-performance liquid chromatography (HPLC) was used to quantify plasmatic (PC) and salivary (SC) concentrations of Mtz. Pharmacokinetic parameters determined were: the highest concentration (Cmax), the time at which Cmax ocurred (Tmax), the area under concentration-time curve from zero to infinity (AUC0-¥), the area under concentration-time curve from zero to t (AUC0-t), distribution volume (VD) and renal clearance (CL). Plasma showed higher Mtz concentration from 6 to 24 hours after drug administration and the highest values concerning Tmax, AUC0-48h and AUC0-¥ than those obtained in saliva (p<0.05). No significant difference was observed between SC and PC for Mtz gel considering all periods tested (p>0.05). Chapter 3: 13 smokers (S) and 13 non-smokers (NS) received a single oral dose of 750 mg Mtz tablet. Blood and saliva samples were collected in different times after oral administration of Mtz. HPLC was used to quantify plasmatic and salivary Mtz concentrations. Pharmacokinetic parameters (ASC, Cmax, Tmax, VD and CL) were determined. A significant reduction in plasmatic Mtz concentration was observed in S compared to NS at 1, 1.5 and 2 hours after administration and in Cmax to plasma (p<0.05). No significant difference was observed in Mtz concentration and pharmacokinetic parameters in saliva (p>0.05). Conclusions: 1) Mtz did not improve the clinical outcomes provided by PD alone; 2) Gel and tablet formulations had similar Mtz bioavailability in plasma and saliva; 3) Some pharmacokinetic parameters were higher in plasma than in saliva concerning Mtz tablet. 4) Smoking interfered with the plasmatic Mtz bioavailability but not the salivary. / Doutorado / Farmacologia, Anestesiologia e Terapeutica / Doutor em Odontologia