<p>Raloksifen je predstavnik selektivnih modulatora estrogenih receptora koji se koristi u terapiji osteoporoze i invazivnog oblika raka dojke u postmenopauzi. Raloksifen se relativno dobro resorbuje iz gastrointestinalnog trakta, ali pri prvom prolasku kroz jetru podleže biotransformaciji u značajnom procentu, &scaron;to je uzrok njegove niske biolo&scaron;ke raspoloživosti. Bioraspoloživost kod ljudi iznosi 2%, a kod Wistar pacova 39%. Različite supstance se koriste da bi se pobolj&scaron;ala bioraspoloživost lekova. Žučne kiseline, kao &scaron;to je deoksiholna kiselina, omogućavaju bolji prolazak kroz biolo&scaron;ke membrane drugim supstancama, te mogu povećati bioraspoloživost lekova. Apigenin je &scaron;iroko rasprostranjeni flavonoid koji inhibi&scaron;e različite metaboličke puteve i na taj način može usporiti metabolizam i eliminaciju i povećati koncentraciju lekova u krvi. Ciljevi ovog istraživanja su bili da se ispita da li apigenin i natrijum-deoksiholat mogu povećati bioraspoloživost raloksifena, njihov uticaj na biohemijske parametre i parametre hemostaze, kao i da se ispita antioksidativni potencijal apigenina. Ispitan je i uticaj apigenina na akutno o&scaron;tećenje jetre usled primene toksične doze paracetamola. U istraživanju su kori&scaron;ćeni zdravi, beli pacovi mu&scaron;kog roda, soja Wistar. U ogledu su ukupno kori&scaron;ćene 84 eksperimentalne životinje. Sva ispitivanja na životinjama je odobrila Etička komisija Univerziteta u Novom Sadu. Raloksifen je primenjen intravenski i per os, dok su natrijum-deoksiholat i apigenin aplikovani peroralno. Uzorci krvi, urina i fecesa su kori&scaron;ćeni za određivanje farmakokinetskih parametara, dok su za određivanje biohemijskih, hemostatskih i parametara oksidativnog stresa kori&scaron;ćeni serum i uzorci jetre laboratorijskih životinja. Pretretman natrijum-deoksiholatom je doveo do smanjenja koncentracije raloksifena u krvi zbog olak&scaron;anog i brzog prodora raloksifena u periferne kompartmane. Time je značajno produženo poluvreme eliminacije i srednje vreme zadržavanja raloksifena i značajno je povećan volumen distribucije raloksifena. Apigenin je doveo do manjeg pada koncentracije raloksifena u prvim satima nakon intravenske primene raloksifena, dok su koncentracije raloksifena bile značajno vi&scaron;e nakon osmog časa od primene leka. Uticaj raloksifena na biohemijske parametre je bio značajno veći nakon intravenske nego nakon peroralne primene. Nakon intravenske primene raloksifena je značajno povećana aktivnost enzima jetre, ALP, ALT, AST i GGT, dok su pokazatelji funkcije bubrega, urea, mokraćna kiselina i kreatinin bili sniženi. U grupama koje su pretretirane natrijum-deoksiholatom i apigeninom vrednosti ovih parametara bile su niže u odnosu na grupu tretiranu samo raloksifenom. Statistički najznačajniji uticaj je imala primena trojne kombinacije, raloksifena, natrijum-deosiholata i apigenina, koja je dovela do značajnog pada aktivnosti enzima jetre, i u odnosu na grupu tretiranu raloksifenom i u odnosu na kontrolnu grupu. Kod životinja tretiranih kombinacijom apigenina i paracetamola pokazatelji toksičnosti su bili značajno niži, naročito vrednosti ALT i ALP, u odnosu na grupu koja je dobijala samo paracetamol. Hepatotoksičnost izazvana toksičnom dozom paracetamola je potvrđena i histopatolo&scaron;kim promenama na jetri, koje nisu primećene u grupi životinja tretiranih kombinacijom apigenina i paracetamola. Ispitivanjem je utvrđeno da apigenin može da spreči paracetamolom indukovano povećanje nivoa MDA, &scaron;to ukazuje da apigenin pozitivno utiče na očuvanje integriteta ćelije. Aktivnost enzima CAT i GR u homogenatima jetre je bila značajno povećana nakon primene toksične doze paracetamola u odnosu na kontrolnu grupu. Aktivnost enzima CAT i GR u grupi tretiranoj kombinacijom apigenina i paracetamola je bila približna vrednostima u kontrolnoj grupi. Na osnovu rezultata istraživanja može se zaključiti da natrijum-deoksiholat i apigenin značajno utiču na farmakokinetiku raloksifena. Primena natrijum-deoksiholata dovela je do pada koncentracije raloksifena u krvi, značajnog prelaska raloksifena iz krvi u periferne kompartmane i povećanja njegovog volumena distribucije, dok je apigenin značajno usporio metabolizam i eliminaciju raloksifena i doveo do njegovog produženog zadržavanja u krvi. Natrijum-deoksiholat i apigenin su pokazali pozitivan uticaj na biohemijske parametre, parametre hemostaze i smanjenje nivoa oksidativnog stresa. Kombinacija natrijum-deoksiholata i apigenina je pokazala sinergistički uticaj na navedene parametre, odnosno dovela je do značajnih promena u odnosu na pojedinačnu primenu ovih supstanci. Rezultati ispitivanja ukazuju na to da apigenin smanjuje stepen lipidne peroksidacije i da dovodi do značajnog povećanja enzimskih antioksidantnih mehanizama odbrane kod pacova kod kojih je hepatotoksičnost indukovana paracetamolom.</p> / <p>Raloxifene is selective estrogen receptor modulator used in treatment of osteoporosis and invasive breast cancer in postmenopausal women. Raloxifene is well absorbed from the gastrointestinal tract, but undergoes extensive first-pass metabolism, which results in very low bioavailability of raloxifene, 2% in humans, and 39% in Wistar rats. Various supstances are used for increasing bioavailability of other drugs. Bile acids, such as deoxycholic acid, promote transport of other supstances through biological membranes, and consequently, may increase their bioavailability. Apigenin is a widespread flavonoid, which inhibits different metabolic pathways. Thus, apigenin can slow down metabolism and elimination of drugs, and raise drug concentration in blood. Aims of this study were to investigate if apigenin and sodium deoxycholate could increase bioavailability of raloxifene, their influence on biochemical and hemostasis parameters, and to investigate antioxidative potential of apigenin. Furthermore, influence of apigenin on acute liver damage after toxic dose of paracetamol was examined. In vivo experiments were performed on 84 laboratory healthy male Wistar rats. All experiments were approved by Ethics Committee of University of Novi Sad. Raloxifene was applied intravenously and per os, while sodium deoxycholate and apigenin were given perorally. Blood, urine and feces samples were used for pharmacokinetic parameters measurement, whereas serum and liver samples were used for evaluation of biochemical, hemostasis and oxidative stress parameters. Pretreatment of sodium deoxycholate led to raloxifene blood concentration decrease due to easier penetration of raloxifene in peripher compartments. As a result, raloxifene half-life and mean residence time were significantly longer and volume of distribution was increased. Apigenin caused lower decrease in raloxifene concentration in first few hours after raloxifene intravenous application, while raloxifene concentrations after apigenin pretreatment were significantlny higher 8 hours after raloxifene application. Influence of raloxifene on biochemical parameters was more significant after intravenous than after per os application. Intravenous application of raloxifene led to increased activity of liver enzymes, ALP, ALT, AST and GGT, while parameters of kidney function, urea, uric acid and creatinine were decreased in comparison to the control group. In experimental groups pretreated with sodium deoxycholate and apigenin these parameters were lower than in the group treated only with raloxifene. Statistically the most significant effects were in the group treated with combination of raloxifene, sodium deoxycholate and apigenin, which caused significant decrease in activity of liver enzymes compared both with raloxifene and control group of animals. In experimental animals treated with combination of apigenin and paracetamol bioindicators of paracetamol toxicity were significantly lower, especially activity of ALT and ALP, in comparison to the group treated only with paracetamol. Hepatotoxicity induced by toxic dose of paracetamol was also confirmed by histopathological alterations in liver, which were not observed in the experimental group treated with combination of apigenin and paracetamol. In this study it was confirmed that apigenin could prevent paracetamol-induced MDA level increase, which suggests that apigenin have positive effects on cell integrity. Activity of CAT and GR in liver homogenates was significantly increased after toxic dose of paracetamol in comparison to the control group, while activity of these enzymes in the group treated with apigenin and paracetamol was similar to values in the control group. Results of this study showed that sodium deoxycholate and apigenin can significantly change pharmacokinetic parameters of raloxifene. Sodium deoxycholate caused signicant decrease in raloxifene blood concentration, extensive distribution from blood to peripheral compartments and increase of raloxifene volume of distribution. Apigenin inhibited metabolism and elimination of raloxifene and thus prolonged half-life and mean residence time of raloxifene. Sodium deoxycholate and apigenin showed positive effects on biochemical and hemostasis parameters and decreased the level oxidative stress. Combination of sodium deoxycholate and apigenin showed synergistic effects on these parameters in comparison to effects of separate application of sodium deoxycholate and apigenin. The result of our study indicates that apigenin inhibits the level of lipid peroxidation and significantly increase the enzyme antioxidant defence mehanisms in paracetamol induced hepatotoxicity in rats.</p>

<p>Uprkos op&scaron;te prihvaćenom stavu da u trudnoći lekove treba izbegavati, veliki broj trudnica tokom trudnoće uzima lekove sa manje ili vi&scaron;e opravdanja. Primena lekova u trudnoći zahteva dodatnu patnju, jer se mora voditi računa o zdravlju majke i zdravlju jo&scaron; nerođenog&nbsp; deteta. Većina lekova koji nalaze primenu u trudnoći, nisu ispitani u kontrolisanim studijama na trudnicama, već se njihov uticaj naljudski fetus, bazira na predpostavkama i kliničkim istraživanjima na životinjama. Odsustvo studija dovodi do toga da se trudnicama obično prepisuju lekovi u dozi za odrasle osobe, koje ne prate fiziolo&scaron;ke promene u trudnoći. Tokom trudnoće u telu trudnica dolazi do promena u funkciji organa i organskih sistema, a zbog nastalih promena menja se i sudbina leka u organizmu. Sistemske bolesti trudnice poput hipertenzije i dijabetesa dovode do hemodinamskih promena i utiču na nastanak patolo&scaron;kih promena posteljice, &scaron;to sve zajedno menja farmakokinetiku lekova i njihov transplacentrarni transport. Ukupno 75 trudnica je uključeno u studiju i podeljeno u tri grupe: zdrave trudnice-kontrolna grupa (n=31), trudnice sa hipertenzijom (n=30) i trudnice sa dijabetesom (n=14). Sve trudnice su u premedikaciji primile iste lekove koji su deo standardne kliničke&nbsp; procedure. Trudnice su primile jednu dozu diazepama intramuskularnom injekcijom (10mg/2ml), a intravenski su primile pojedinačne doze cefuroksima (1,5g), metoklopramida (10mg/2ml) i ranitidina (50mg/2ml). Od svakog para majka-dete ukupno je analizirano po 5 uzoraka. Uzorci krvi od majke uzimani su u tri vremenske tačke: nakon davanja leka, u momentu ekstrakcije deteta i nakon porođaja. Uzorci&nbsp; krvi&nbsp; deteta&nbsp; uzimani su&nbsp; nakon&nbsp; porođaja iz pupčane vene i arterije. Prikupljeni uzorci plazme analizirani su metodom tečne hromatografije visokih performansi (HPLC). Istraživanje je pokazalo da lekovi&nbsp; primenjeni u premedikaciji&nbsp; carskog reza prolaze transplacentarnu membranu i da se ni jedan&nbsp; od&nbsp; lekova&nbsp; primenjenih&nbsp; u studiji nije akumulirao u fetusu i nije imao neželjeno dejsvo na novorođenče. Cefuroksim, ranitidin i metoklopramid pokazali su nizak feto-maternalni transfer, dok je diazepam pokazao visok&nbsp; feto-maternalni transfer. Izmerene koncentracije cefuroksima u plazmi trudnica u momentu porođaja bile su &ge;8 &mu;g/ml, &scaron;to je koncentracija veća od MIC za većinu patogena odgovornih za nastavak infekcija u aku&scaron;erstvu. Koncentracije cefuroksima u fetalnoj plazmi bile su &ge;4&mu;g/ml &scaron;to je veće od&nbsp; MIC koncentracija za veliki broj patogena. Gestacijska starost trudnoće nije uticala na obim prolaska cefuroksima&nbsp; kroz placentu, koji je prolazi uglavnom pasivnom difuzijom. Farmakokinetski parametri cefuroksima razlikovali su se kod hipertenzivnih i dijabetičnih trudnica, u odnosu kontrolnu grupu, ali ove bolesti nisu imale značajan uticaj na smanjenje terapijske efikasnosti cefuroksima. Farmakokinetika cefuroksima kod hipertenzivnih&nbsp; trudnica&nbsp; ukazala je na bržu eliminaciju cefuroksima iz krvi majke i na veću distribuciju leka u okolna tkiva. U dijabetičnoj grupi trudnica i novorođenčadi koncentracije cefuroksima su bile vi&scaron;e u odnosu na druge ispitivane grupe, dok je feto-maternalni odnos bio niži, &scaron;to ukazuje na postojanje strukturalne i funkcionalne pomenu posteljice u dijabetesu. Hipertenzija i dijabetes trudnica nisu imali uticaj na prodor ranitidina kroz placentu. Hipertenzija i dijabetes trudnica nisu uticali na većinu farmakokinetskih parametara ranitidina, mada je zabeleženo smanjenje volumena distribucije u ovim grupama trudnica, &scaron;to bi moglo da ukazuje na njihovu hemodinamsku nestabilnost i povećanje slobodne frakcije ranitidina. Koncentracija metoklopramida bila veća u krvi majki u odnosu na krv fetusa. Transport metoklopramida iz fetusa ka majci bio je dominantniji, a naročito u hipertenzivnoj i dijabetičnoj grupi trudnica. Hipertenzija i dijabetes trudnica uticali su na zadržavanje metoklopramida u fetusu. Koncentracije dijazepama u majčinoj i fetalnoj krvi bile su vi&scaron;e u kontrolnoj i hipertenzivnoj grupi trudnica. Hipertenzija i dijabetes trudnica povećavaju&nbsp; transfer diazepama kroz placentu, povećanjem koncentracije slobodnih masnih kiselina, steroidnih hormona, smanjenjem vezivnog kapaciteta potencijalna opasnost od neželjenog dejstva diazepama i njegovih metabolita na fetus i novorođenče. Ova doktorska studija ukazuju na potrebu obimnijih farmakokinetskih istraživanja kako na zdravim tako i na bolesnim trudnicama, koja će dati zaključke utvrđene na dokazima i pomoći u individualnom terapijskom pristupu svakoj trudnici.</p> / <p>In spite of&nbsp; the widespread opinion&nbsp; that&nbsp; drugs should be avoided in pregnancy, a great number of&nbsp; pregnant&nbsp; women&nbsp; take drugs with more or less justification.&nbsp; Administration of drugs in pregnancy requires additional attention because the health of&nbsp; both the mother and&nbsp; her unborn child must be protected. Majority of drugs administered in pregnancy have not been tested&nbsp; within the controlled studies performed on pregnant women, but&nbsp; their effect on the human foetus is based on assumptions and clinical trials performed on animals. This absence of studies results in the situation that pregnant&nbsp; women are usually prescribed drugs in a dose&nbsp; for adults, which does not take into account the physiological changes happening in pregnancy. During pregnancy, the pregnant woman&rsquo;s body undergoes changes in the<br />functions of organs and organ systems. These changes further affect the destiny of a&nbsp; drug in the organism. In pregnant women, systemic diseases such as hypertension&nbsp;&nbsp; and diabetes mellitus lead to hemodynamic changes and cause pathological&nbsp; changes in placenta, thus changing the pharmacokinetics of drugs and their transplacental transport. The study sample consisted of 75 pregnant women, who were divided into three groups as follows: the control group included healthy pregnant&nbsp; women (n=31), a group of pregnant women&nbsp; with&nbsp; hypertension (n=30) and&nbsp; a group of&nbsp; those&nbsp; with&nbsp; diabetes mellitus (n=14). All of them were administered the same drugs as a part of standard clinical procedure in premedication. The pregnant women received a single dose of diazepam by intramuscular injection (10mg/ml), and individual doses of cefuroxime (1.5mg), metoclopramide (10mg/2ml) and ranitidine (50mg/2ml). Five samples taken from each mother-infant pair were analyzed. Blood samples were taken from the mother three times: after drug administration, at the moment of extraction of baby and after delivery. Baby&rsquo;s blood samples were taken from the umbilical cord vein and artery after delivery. Plasma samples were analyzed by the method of high-performance liquid chromatography (HPLC). The research has shown that drugs administered in premedication of caesarean section went through the transplacental membrane and that none of the tested drugs accumulated in the foetus and had an adverse effect on the newborn. Cefuroxime, ranitidine and metoclopramide were shown to have a low transfer between the mother and her foetus, whereas diazepam showed a high foetal-maternal transfer. Cefuroxime concentrations measured in the pregnant woman&rsquo;s and foetal plasma at the moment of delivery were &ge;8&mu;g/ml and &ge;4&mu;g/ml, respectively, that&nbsp; being above the minimum inhibitory concentration (MIC) for most pathogens responsible for the development of infection in obstetrics. Gestational age had no effect on the range of cefuroxime flow through the placenta, which happens mostly by&nbsp; passive diffusion. Pharmacokinetic parameters of cefuroxime differed in the pregnant&nbsp; women having hypertension and diabetes mellitus from the controls; however, these diseases did not significantly reduce the therapeutic efficacy of cefuroxime. Pharmacokinetics of cefuroxime indicated faster elimination of&nbsp; cefuroxime into the maternal blood and greater distribution of the drug into the surrounding tissues in the hypertensive pregnant women. In the group consisting of pregnant women and newborns having diabetes, the cefuroxime concentrations were higher than in other groups, whereas foetal-maternal relation was lower, which suggests the presence of structural and functional change in the placenta in diabetes. Hypertension and diabetes mellitus had no affect either on the flow of ranitidine through the placenta in the pregnant women or on&nbsp; the&nbsp; majority of pharmacokinetic parameters of ranitidine, although a certain reduction in the volume&nbsp; of distribution was recorded in these groups of pregnant women, which could suggest their hemodynamic instability and increased free fractions of ranitidine. The concentration of metocloporamide was higher in the maternal blood than in the&nbsp; foetal blood, and&nbsp; the transport of metocloporamide from the foetus towards the mother was more dominant, particularly in&nbsp; the&nbsp; group of&nbsp; hypertensive and diabetic&nbsp;&nbsp;&nbsp; pregnant women. Metoclopramide tended to retain in the foetuses of mothers having&nbsp; hypertension and diabetes. The concentrations of diazepam in maternal and foetal blood were higher in the controls&nbsp; and hypertensive&nbsp; pregnant&nbsp; women. Hypertension and diabetes in pregnant&nbsp; women increase the transfer of diazepam through the placenta by increasing the concentration of free fatty acids and steroid hormones and by reducing the binding capacity of carrier proteins and the concentration of plasma&nbsp;&nbsp; proteins, thus increasing the potential danger of adverse effects of diazepam and its metabolites on the foetus and the newborn. This doctoral study suggests the necessity for more extensive pharmacokinetic research including both healthy and affected pregnant women that would lead to conclusions based on evidence and help to develop individual therapeutic approach to each pregnant woman.</p>

<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>

Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Zdeněk Záboj Supervisor: PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: Study of drugs interactions of antiviral drugs with intestinal transporters Sofosbuvir is an antiviral agent widely used in the treatment of chronic hepatitis C. This orally administered prodrug is a designed substrate of ATP-binding (ABC) efflux transporters, P- glycoprotein (ABCB1) and breast cancer resistance protein (ABCG2). ABCB1 and ABCG2 are important determinants of intestinal absorption and are the site of significant pharmacokinetic drug interactions, leading to changes in drug exposure. Pharmacokinetic drug interactions may be undesirable (increasing the toxicity of the treatment) or desirable (allowing dose reduction). Because sofosbuvir is often administered in combination regimens with other anti(retro)virotics, the aim of this thesis was to study the ability to enhance intestinal absorption of sofosbuvir. To study the pharmacokinetic drug interactions on ABCB1 and ABCG2, a widely established in vitro bi-directional transport method through a polarized monolayer formed by the Caco-2 cell line derived from colorectal cancer has been used. We analyzed the drug interactions of sofosbuvir on these efflux...

- 8 - ABSTRACT (EN) The thesis is submitted as a commented set of reviewed publications documenting and depicting the possibilities of mass spectrometry in the field of chemical, biological and pharmaceutical research; namely for the purposes of structure elucidation of selected organometallic complexes, analyses of drugs and their metabolites, monitoring of important biological markers. In course of experimental work, the following objectives were studied and solved:  Proposal and realization of micro-scale preparation of selected rhenium complexes with aromatic ligands, utilizing tetrabutyammonium tetrachlorooxorhenate as a starting material; preparation and structure characterization of oxorhenium(V) complexes with 1,2-dihydroxybenzene, 1,2,3-trihydroxybenzene, and 2,3- dihydroxynaphtalene as ligands by means of ESI/MS, APPI/MS and LDI-MS; ESI/MS and UV/Vis study of kinetic behavior of complexes arising from the reaction of tetrabutylamonnium tetrachlooxorhenate with pyrogallol and catechol as ligands. Special aim was devoted to the study of subsequent chemical transformation of primarily formed Re(V) complexes; structure characterization of selected ferrocene complexes with copper, gold and silver by means of ESI/MS.  Proposal of methodology of structure characterization and quantification of the...