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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Desenvolvimento de metodologia para mapeamento petídico da Eritropoetina Humana Recombinante visando o controle em processo da produção em Bio-Manguinhos

Araujo, Ana Paula de January 2011 (has links)
Submitted by Priscila Nascimento (pnascimento@icict.fiocruz.br) on 2012-11-29T13:14:34Z No. of bitstreams: 1 ana-paula-araujo.pdf: 1867740 bytes, checksum: ab9d7b2866753474ebe7ecb95d8e32d9 (MD5) / Made available in DSpace on 2012-11-29T13:14:34Z (GMT). No. of bitstreams: 1 ana-paula-araujo.pdf: 1867740 bytes, checksum: ab9d7b2866753474ebe7ecb95d8e32d9 (MD5) Previous issue date: 2011 / Fundação Oswaldo Cruz. Instituto de Tecnologia em Imunobiológicos. Rio de Janeiro, RJ, Brasil. / A eritropoetina (EPO) é um hormônio produzido, principalmente, pelos rins, que regula a produção de células vermelhas do sangue. Trata-se de uma glicoproteína com 166 aminoácidos, três sítios de N-glicosilação e um de O-glicosilação. Apresenta massa molecular na faixa de 30-34 kDa, sendo aproximadamente 40% correspondente aos glicídeos. A EPO está disponível como agente terapêutico produzido através da tecnologia do DNA recombinante em cultura de células de mamíferos. A EPO humana recombinante (rHuEPO) é usada para o tratamento de anemia associada à insuficiência renal crônica. Devido a relevância médica da rHuEPO, sua produção está sendo nacionalizada através do processo de transferência de tecnologia do Centro de Inmunología Molecular (CIM), de Cuba, para o Instituto de Tecnologia de Imunobiológicos (Bio-Manguinhos)/FIOCRUZ. O controle de qualidade sobre o processo produtivo da rHuEPO e seu produto final é bastante rigoroso. Neste contexto, o mapeamento peptídico é um dos mais importantes ensaios usados no controle em processo da produção de proteínas recombinantes. Este ensaio assegura a integridade da estrutura primária das proteínas ao final das etapas de suas purificações. Sendo assim, o objetivo desta dissertação de mestrado foi definir uma metodologia de mapeamento peptídico da rHuEPO, visando o controle de processo da produção deste biofármaco em Bio-Manguinhos. Previamente, a preparação da rHuEPO fornecida pelo CIM foi avaliada quanto a sua homogeneidade e caracterizadapor eletroforeses em gel de poliacrilamida, cromatografia de fase reversa, cromatofocalização eespectrometria de massa. Para obter os peptídeos da rHuEPO, a hidrólise enzimática desta glicoproteína com a enzima tripsina foi avaliada em diferentes tempos de incubação e com relações enzima/substrato distintas. O fracionamento dos peptídeos foi feito por cromatografia líquida de fase reversa em coluna C18, empregando-se diferentes colunas cromatográficas e gradientes de eluição. As principais frações peptídicas isoladas da cromatografia de fase reversa foram analisadas por espectrometria de massa a fim de comprovar a identidade dos peptídeostrípticos da rHuEPO. A especificidade da metodologia desenvolvida foi avaliada através da comparação dos perfis peptídicos do hidrolisado tríptico da rHuEPO e do quimotripsinogênio A. A hidrólise tríptica usando-se relação enzima/substrato de 1/50 (p/p), concentração de rHuEPO de 1 mg/mL e incubação de 1 hora a 37o C hidrolisou mais de 99% da glicoproteína. As colunas cromatográficas de fase reversa Hi-Pore RP 318, Vydac 218TP C18 e Delta Pak C18 se mostraram aptas para o fracionamento dos peptídeos trípticos da rHuEPO. Em comparação à metodologia usada no CIM, o tempo de incubação de hidrólise foi reduzido em, pelo menos,2 horas e a duração da corrida cromatográfica para obtenção do mapa peptídico diminuiu em, pelo menos, 1 hora e 42 minutos. Na análise por espectrometria de massa das frações isoladas da cromatografia de fase reversa, seis peptídeos trípticos da rHuEPO foram observados. Tais frações peptídicas foram identificadas como pertencentes à EPO humana pelo programa Mascot Search Results. Dessa forma, ficou estabelecida uma metodologia de mapeamento peptídico especifica, simples e rápida para ser utilizada no controle em processo da produção da rHuEPO em Bio-Manguinhos. / Erythropoietin (EPO) is a hormone produced mainly by the kidney that regulates the production of red blood cells. It is a glycoprotein with 166 amino acids, three N-glycosylation and one O-glycosylation sites. It has a molecular weight in the range of 30-34 kDa, being approximately 40% of its content corresponding to carbohydrates. EPO is available as a therapeutic agent produced by recombinant DNA technology in mammaliancell culture. The recombinant human EPO (rHuEPO) is used to treat anemia associated with chronic renal disease. Due to rHuEPO medical relevance, its production technology is a subject of transference from the Centro de Inmunología Molecular(CIM), Cuba, to the Instituto de Tecnologia em Imunonobiologicos(Bio-Manguinhos)/FIOCRUZ. The quality control over production process of rHuEPO and its final product is quite rigorous. In this context, peptidemapping is one of the most important tests used in process control of recombinant proteins production. This test ensures the primary structure integrity of a protein after its purification processes. Thus, the objective of this dissertation was to define a methodology for peptide mapping of rHuEPO aiming to be used in the process control of this biopharmaceutical production in Bio-Manguinhos. Previously, the preparation of rHuEPO provided by CIM was characterized by polyacrylamidegel electrophoresis, reversed phase chromatography, chromatofocusing and mass spectrometry. In order to obtain rHuEPO peptides, the enzymatic hydrolysis of this glycoprotein with the enzyme trypsin was assessed at differents incubation times and enzyme/substrate ratio. Peptides fractionation was performed by reverse phase liquid chromatography, using distincts C18 columns and elution gradients. The main peptide fractions from reversed phase chromatography were analyzed by mass spectrometry to confirm the identity of rHuEPO tryptic peptides. The specificity of the developed methodology was evaluated by comparing peptides profiles from rHuEPO and Chymotrypsinogen A tryptic hydrolysates. The tryptic digestion using enzyme/substrate ratio of 1/50 (w/w), substrate concentration of 1 mg/mL and incubation for 1 hour at 37°C hidrolysated more than 99% of the glicoprotein. The reversed phase columns Hi-Pore RP318, Vydac 218TP C18 e Delta Pak C18 were able to fractionate the rHuEPO tryptic peptides. Compared to the methodology used in CIM, the hydrolysis incubation time was reduced by at least 2 hours and the chromatographic running time to obtain the peptide map was decreased by at least 1 hour and 42 minutes. The mass spectrometry analysis of the fractions isolated from reversed-phase chromatography showed six tryptic peptides of rHuEPO. These peptide fractions were identified as belonging to human EPO by the program Mascot Search Results. Thus it was established an specific, simple and fast peptide mapping methodology to use in process control of rHuEPO in Bio-Manguinhos.
2

In silico određivanje fizičko-hemijskih, farmakokinetskih i toksikoloških parametara i in vitro ispitivanje antiproliferativne aktivnosti novosintetisanih derivata N-sukcinimida / In silico physico-chemical, pharmacokinetic and toxicologic parameters determination and in vitro antiproliferative activity evaluation of newly synthesized succinimide derivatives

Ćurčić Jelena 30 July 2020 (has links)
<p>Sukcinimidi su jedinjenja koja pokazuju vi&scaron;estruke farmakolo&scaron;ke efekte uključujući i antiproliferativnu aktivnost, zahvaljujući prisustvu farmakofore sa dva hidrofobna regiona i dva regiona bogata elektronima. Savremeni dizajn lekova ima za cilj da se modifikacijama u strukturi (promena vrste, položaja i orijentacije supstituenata) i in silico računarskim metodama predvide i optimizuju farmakokinetske osobine i bezbednosni profil kandidata za lek. U ranoj fazi razvoja lekova se koriste postojeće baze podataka o molekulskim, farmakokinetskim i toksikolo&scaron;kim parametrima već ispitanih jedinjenja i pomoću matematičkih modela i algoritama predviđaju se osobine novih molekula, elimini&scaron;u se neodgovarajući kandidati i postiže se u&scaron;teda u vremenu i materijalnim sredstvima. Da se ispitaju fizičko-hemijske karakteristike 11 novosintetisanih metil-etil-N-aril-sukcinimida na osnovu strukture, primenom različitih softverskih paketa; da se na osnovu strukture odrede farmakokinetski i toksikolo&scaron;ki parametri, primenom različitih softverskih paketa; da se ispita retenciono pona&scaron;anje, odnosno odrede retencione konstante za svako jedinjenje primenom visokoefikasne hromatografije na tankom sloju (HP-TLC) i ispita mogućnost primene retencionih konstanti kao mere lipofilnosti ispitivanih jedinjenja; da se ispita antiproliferativna aktivnost na odabranim kulturama ćelija karcinoma i na zdravim ćelijama fibroblasta pluća; da se analizom molekulskog dokinga ustanovi vezivanje za estrogene receptore. Ispitano je retenciono pona&scaron;anje 11 novosintetisanih derivata sukcinimida primenom visokoefikasne hromatografije na tankom sloju (HP-TLC) obrnute faze uz primenu dvokomponentne sme&scaron;e vode i organskog rastvarača (metanola, acetonitrila ili acetona), sa odgovarajućim zapreminskim udelom organskog rastvarača kao mobilne faze. Iz razvijenih hromatograma su izračunate retencione konstante RM0 i S. Logaritam podeonog koeficijenta (logP) određen je in silico, kori&scaron;ćenjem različitih računarskih programa. In silico su određene fizičko-hemijske karakteristike, farmakokinetski parametri, toksikolo&scaron;ki parametri, akvatična toksičnosti i afinitet vezivanja za estrogene receptore. Izračunate su vrednosti afiniteta za 4 vrste receptora (G-protein spregnuti receptori, jonski kanali, inhibitori kinaza, nuklearni receptori). Antiproliferativna aktivnost ispitivanih derivata sukcinimida određena je primenom kolorimetrijskog testa sa tetrazolijum solima (MTT testa) na komercijalnim kulturama ćelija (MRC-5, A549, HeLa, MDA-MB-231, MCF-7, HT-29) i izračunate su IC50 vrednosti. Urađena je i doking analiza sukcinimida prema ERA (estrogen receptor alfa) i ERB (estrogen receptor beta) i dobijene su vrednosti energije formiranja kompleksa sa posmatranim receptorima (MolDock Score). Statistički najznačajnije linearne korelacije dobijene su između eksperimentalno određenih hromatografskih parametara (RM0 i S) i in silico parametara lipofilnosti MlogP i ClogP. Ispitivanjem uticaja promene RM0 i S na farmakokinetske karakteristike dobijeni su rezultati koji pokazuju paraboličnu zavisnost konstante apsorpcije (Ka) i procenta vezivanja za proteine plazme (PPB) od posmatranih retencionih konstanti, dok je zavisnost sa volumenom distribucije (Vd) i sposobno&scaron;ću prolaska kroz krvno-moždanu barijeru (logBBB) bila linearnog tipa. Toksičnost ispitivanih jedinjenja, procenjena na osnovu in silico dobijenih LD50 vrednosti, nije bila vi&scaron;a od toksičnosti već registrovanih lekova sa strukturom sukcinimida, i dala je parabolične zavisnosti u odnosu na RM0 i S vrednosti. Eksperimentalno nijedno od ispitivanih jedinjenja nije pokazalo aktivnost u odnosu na zdrave fibroblaste pluća. Najznačajniju antiproliferativnu aktivnost (najniže IC50) su pokazala jedinjenja 6 i 7 u odnosu na ćelije linije MCF-7 i jedinjenje 11 u odnosu na A549 ćelijsku liniju. Doking analiza je pokazala niže energije formiranja kompleksa sa ERA, u odnosu na ERB. Eksperimentalno određeni parametri RM0 i S se mogu koristiti kao alternativne i pouzdane mere lipofilnosti analiziranih sukcinimida. Ispitivana jedinjenja pokazuju povoljne fizičko-hemijske karakteristike, predviđene in silico metodama i povoljne farmakokinetske karakteristike: male vrednosti konstante apsorpcije, umeren volumen distribucije, povoljan afinitet vezivanja za proteine plazme, favorizovan prolazak kroz krvno-moždanu barijeru za lipofilnija jedinjenja. Procenjuje se da sva ispitivana jedinjenja, izuzev derivata sa &ndash;CN supstituentom, imaju zahtevani nizak stepen toksičnosti. Po antiproliferativnoj aktivnosti u odnosu na ćelije ER-zavisnog karcinoma dojke (MCF-7) izdvajaju se jedinjenja sa metil i nitro supstituentom u para položaju. Na osnovu malih energija formiranja kompleksa sa ERA, koji su eksprimirani na ćelijama MCF-7 linije, pretpostavlja se da bi mehanizam njihovog delovanja delimično mogao biti obja&scaron;njen uticajem na ERA, ali su potrebna dodatna istraživanja na tom polju.</p> / <p>Succinimides have exhibited various pharmaceutical effects including antiproliferative activity due to an important structural fragment (a pharmacophore) presented in form of two hydrophobic regions and two electron-rich centers. Current development of new drugs involves modifications in structure (type, position and orientation of substituents) and usage of in silico computational programs to predict and optimize pharmacokinetic and safety profile of drug candidates. In early phase of drug development, databases regarding the molecular, pharmacokinetic and toxicological parameters of already tested compounds are used, mathematical models and algorithms are applied for predicting the properties of new molecules and inadequate candidates are eliminated saving time and resources. Determination of physico-chemical properties of the analyzed methyl-ethyl-N-phenilsuccinimide derivatives by software packages; virtual pharmacokinetic and toxicology screening; investigation of retention behavior of the compounds by the reversed-phase HPTLC analysis and calculation of retention constants and their correlation with lipophilicity; in vitro evaluation of antiproliferative activity toward five carcinoma cell lines and normal fetal lung cell line; molecular behavior study on target estrogen receptors by molecular docking and correlation of antiproliferative activity toward ER+ breast carcinoma cell lines and in silico estrogen receptor affinity binding. Retention behavior of 11 newly synthesized succinimide derivatives was determined by reversed phase high performance thin layer chromatography (RP HPTLC) with the application of two-component mixtures water - organic solvent (methanol, acetonitrile or acetone) with adequate volume fractions of the organic modifier. After chromatographic development RM0 and S parameters were calculated. The logarithm of partition coefficient, logP for the analyzed compounds were calculated by different softwares. Physico-chemical properties, pharmacokinetic and toxicological parameters, aquatic toxicity and relative affinity to estrogen receptors were predicted in silico. The affinity toward 4 types of receptors (G-proteine coupled receptors, ion channels, kinase inhibitors, nuclear receptors) were calculated as well. Standard MTT assay was applied to evaluate cytotoxic activities of the analyzed succinimides after cells were exposed. Antiproliferative activity were investigated toward commercial MRC-5, A549, HeLa, MDA-MB-231, MCF-7, HT-29 cell lines and IC50 values were calculated for each compound. MolDock Score that represents energy of binding to estrogen alfa and estrogen beta receptors was determined by molecular docking. Statistically significant linear correlations were determined between the chromatographic retention constants (RM0 and S) and calculated logP, and the best two were obtained in correlation of retention constants with MlogP and ClogP. The examination of RM0 and S influence on pharmacokinetics indicated parabolic dependence of the absorption constant (Ka) and plasma protein binding predictor (PPB) from the observed constants while the volume of distribution (Vd) and the ability to cross the brain blood barrier (logBBB) had linear association with the retention parameters. The toxicity of the analysed compounds evaluated in silico as LD50 on rodents was lower in comparison with the drugs with succinimide structure that are on the market and had parabolic correlation with the RM0 and S values. The experiments indicated that none of the compounds examined had cytotoxic activity toward the healthy lung fibroblast cells. The results of the in vitro assay shown that none of the investigated compounds demonstrated antiproliferative activity toward fetal lung cells. The most potent antiproliferative agents were compounds 6 and 7 toward MCF-7 cell line, and compound 11 toward A549 cell line. Molecular docking shown lower energy for binding to ERA in comparison to ERB.</p>

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