Search

Dyslipidemia and obesity are recognized as two of the major global health issues and main risk factors for coronary heart disease and cerebrovascular disease. In recent years, carob has shown certain antioxidant and anti-dyslipidemic potential. In this study, Wistar rats were fed with a standard and cholesterol-enriched diet and treated orally with carob extract and simvastatin for four weeks. After sacrifice, blood samples were collected for biochemical analysis, and liver tissue was taken for histological and immunohistochemical assessment. Weight gain was significantly higher in groups fed with cholesterol-fortified granules; total cholesterol was found to be significantly lower in the hypercholesterolemic groups treated with simvastatin and simvastatin/carob combined regimens compared with hypercholesterolemic animals treated with saline (p < 0.05). The same was true for low-density lipoprotein cholesterol and the LDL/HDL ratio (p < 0.05). Adiponectin was remarkably higher in animals treated with simvastatin compared to all other groups (p < 0.05). Leptin was significantly lower in groups treated with carob and simvastatin compared to the hypercholesterolemic group treated with saline (p < 0.05). Carob/simvastatin co-administration reduced hepatocyte damage and improved liver morphology. A study confirmed the anti-dyslipidemic, anti-obesity, and hepatoprotective potential of carob pulp alone or in combination with simvastatin in the treatment of high-fat diet-fed rats.

Doktorska disertacija posvećena je implementaciji mikrodijalizne metode za in vivo uzorkovanje levofloksacina i daidzeina iz intersticijalne tečnosti poprečno-prugastog mišića, i ispitivanju interakcije ove dve supstance u cilju povećanja terapijske efikasnosti levofloksacina. Takođe je ispitana i bezbednost konkomitantne primene levofloksacina i daidzeina. Uticaj daidzeina na prodor levofloksacina pasivnom difuzijom ispitan je PAMPA metodom. Na animalnom modelu, nakon oralne primene levofloksacina i daidzeina pojedinačno i u kombinaciji određene su koncentracije navedenih supstanci u plazmi, intersticijalnoj tečnosti mišića buta primenom mikrodijalizne metode i u homogenatima tkiva. Razvijena je metoda visokosenzitivne tečne hromatografije za detekciju obe supstance u plazmi i uzorcima dijalizata. Ispitan je uticaj daidzeina na farmakokinetiku levofloksacina u plazmi, mišiću, bubregu, jetri, plućima, mozgu, urinu i fecesu. Takođe je ispitan uticaj daidzeina na osetljivost bakterija na levofloksacin, u cilju ispitivanja mogućnosti njegove primenjivosti kao inhibitora efluks pumpi. Interakcija daidzeina i levofloksacina ispitana je na kliničkim izolatima bakterija primenom modifikovane metode šahovske ploče. In silico ispitivanjima određene su interakcije levofloksacina i daidzeina na nivou transportera. Levofloksacin se nakon peroralne primene rapidno distribuiše postižući visoke koncentracije u plazmi i u intersticijumu, sa indeksom distribucije u tkiva od 0,78, ali sa velikim interindividualnim razlikama u vrednostima maksimalnih koncentracija u tkivu. Nakon peroralne primene, uzorkovanja plazme i primene mikrodijalize, pokazano je da se daidzein distribuiše u mišićno tkivo, sa indeksom distribucije u tkiva od 0,35. Daidzein je doveo do povećanja slobodnih koncentracija levofloksacina u mišiću, mozgu, smanjio izlučivanje levofloksacina u urin i doveo do povećanja koncentracija levofloksacina u fecesu. Zajednička primena daidzeina i levofloksacina nije imala negati, This doctoral dissertation is dedicated to the implementation of microdialysis method for the in vivo sampling of levofloxacin and daidzein in striated muscle, and to the study of the interaction between these compounds with the aim of increasing therapeutic efficacy of levofloxacin. The safety of concomitant use of levofloxacin and daidzein was also examined. The effect of daidzein on the penetration of levofloxacin by passive diffusion was investigated by the PAMPA method. In an animal model, after oral administration of levofloxacin and daidzein individually and in combination, the concentrations of both substances were determined in plasma, muscle interstitial fluid and in tissue homogenates. A high-performance liquid chromatography method was developed for the detection of levofloxacin and daidzein in plasma, dialysate and tissue samples. The effect of daidzein on the pharmacokinetics of levofloxacin in plasma, muscle, kidney, liver, lung, brain, urine and feces was examined. The effect of daidzein on bacterial susceptibility to levofloxacin was determined to examine its potential use as an efflux pump inhibitor. The interaction of daidzein and levofloxacin was investigated on clinical isolates of bacteria by the modified checkerboard method. Interactions between levofloxacin and daidzein at the transporter level have been studied using in silico methods. Levofloxacin rapidly distributed after oral administration, achieving high plasma and interstitial muscle fluid concentration, with a tissue distribution index of 0.78, but with large interindividual differences in maximum tissue concentrations. Following oral administration, plasma sampling, and microdialysis, daidzein has been shown to distribute into muscle tissue with a tissue distribution index of 0.35. Daidzein led to an increase in the free concentrations of levofloxacin in muscle, brain, decreased urinary excretion of levofloxacin and an increase in levofloxacin concentration in feces. Concomitant use

Interindividualne razlike u sastavu i aktivnosti crevne mikroflore mogu uticati na metabolizam lekova kao i na njihov konačan terapijski odgovor. Simvastatin je lek iz grupe statina i karakteriše ga izuzetno mala rastvorljivost u vodi, mala bioraspoloživost (<5%) i velike interindividualne razlike u terapijskom odgovoru čiji uzroci nisu u potpunosti objašnjeni. Poslednjih godina velika pažnja se posvećuje ispitivanjima žučnih kiselina u razvoju novih farmaceutskih formulacija zbog svoje uloge u solubilizaciji i modifikaciji prodora lekova kroz biološke membrane. Zbog svega navedenog, u fokusu našeg istraživanja su bile potencijalne interakcije između simvastatina, probiotskih bakterija i žučnih kiselina o kojima se vrlo malo zna, a od izuzetne su važnosti, zbog mogućeg uticaja na farmakokinetske i farmakodinamske osobine simvastatina, pa samim tim i na konačan terapijski odgovor kod pacijenta.Cilj istraživanja je bio da se ispita prodor i metabolizam simvastatina u probiotskim bakterijama kao i uticaj različitih žučnih kiselina na transport ovog leka u bakterijske ćelije. Takođe, cilj je bio da se ispita uticaj soli žučnih kiselina na distribucioni koeficijent simvastatina, kao i interakcije žučnih kiselina sa simvastatinom na nivou transportnih proteina probiotskih bakterija kako bi se objasnila priroda očekivanih interakcija.Identifikacija i kvantifikacija uzoraka vršena je metodom tečne hromatografije sa masenom spektrometrijom (LC-MS/MS). Korišćenjem programskih paketa VolSurf+ i Molinspiration, za identifikovane metabolite su izračunati molekulski deskriptori koji opisuju fizičko-hemijske i farmakokinetske osobine molekula. Određivanje distribucionog koeficijenta vršeno je Shake-flask metodom. Interakcije žučnih kiselina sa simvastatinom na nivou transportnih proteina probiotskih bakterija ispitane su doking studijama pomoću SwissDock programa. Prilikom dvadesetčetvoročasovne inkubacije sa probiotskim bakterijama uočen je statistički značajan pad koncentracije, Interindividual differences in the composition and activity of the gut microflora may affect the metabolism of drugs as well as their final therapeutic response. Simvastatin is drug from the group of statins and has extremely low water solubility, low bioavailability (<5%) and high interindividual differences in therapeutic response whose causes are not fully understood. In recent years, great attention has been paid to studies of bile acids in the development of new pharmaceutical formulations because of their role in the drug solubilization and modification of drug transport through biological membranes. Accordingly, interactions between simvastatin, probiotic bacteria and bile acids were the focus of our research due to great importance and potential influence on the pharmacokinetic and pharmacodynamic properties of simvastatin, and therefore the final therapeutic response in the patients. The aim of the study was to investigate the simvastatin transport and metabolism in probiotic bacteria as well as the effect of various bile acids on drug transport into the bacterial cell. Additonally, the aim was to investigate the influence of bile salts on the distribution coefficient of simvastatin, and the interactions of bile acids with simvastatin at the level of probiotic transport proteins in order to elucidate the nature of expected interactions. Identification and quantification of samples were performed with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Molecular descriptors that describe the physico-chemical and pharmacokinetic properties of identified metabolites were calculated using the software packages VolSurf+ and Molinspiration. Determination of the distribution coefficient was performed using Shake-flask method. Interaction of bile acids with simvastatin at the level of bacterial transport proteins were studied using docking studies with SwissDock program. During the twenty-four hours of incubation with probiotic bacteria, simvastatin concentr

Uvod: U prošlosti žučne kiseline su uglavnom razmatrane sa stanovišta njihove funkcije koju obavljaju u crevima jer posreduju u varenju masti i apsorpciji liposolubilnih vitamina. Nedavne studije potvrđuju da žučne kiseline ne igraju samo ulogu u varenju masti, nego se ponašaju i kao signalni molekuli koji stupaju u interakciju sa raznim receptorima uključujući nuklearne receptore i receptore vezane za G-proteine. Kao amfipatični molekuli one su sposobne da reaguju sa fosfolipidima ćelijskih membrana i da poboljšavaju prolazak lekova kroz njih. Stoga se žučne kiseline razmatraju kao promoteri u bukalnim, okularnim i nazalnim farmaceutskim formulacijama. Cilj: Svrha ovog istraživanja je bila da se ispitaju žučne kiseline i njihovi okso derivati kao jedinjenja koja utiču na propustljivost ćelijskih membrana i prolazak lekova do ciljnih tkiva. Materijal i metod: Interakcije makrolidnih antibiotika i žučnih kiselina su ispitivane uz pomoć NMR difuzionih merenja i relaksacije paramagnetičnim jonima. Retencioni parametri odabranih žučnih kiselina su dobijeni korišćenjem hromatografije na normalnim fazama i evaluisani su primenom pet različitih softvera. In vivo ekaperimenti su sprovedeni na 126 eksperimentalnih životinja koje su bile podeljene u 21 grupu. Rezultati: Vezivanje žučnih kiselina za micele je indikovano razlikama u hemijskom pomeranju makrolida i proširenju signala kao posledica redukovane mobilnosti unutar micela. Dodatak micela žučnih kiselina povećava solubilizaciju makrolida za faktor približno 2-3. Sprovedena korelaciona analiza pokazala je značajnu zavisnost između faktora retencije i intestinalne apsorpcije, prodora u MDCK epitelne ćelije, permeabilnost kroz kožu, logBB i PPB%. Putem implementacije in vivo eksperimentalnog dela pokazano je da žučne kiseline utiču na prolazak makrolida u tkivo mozga, bubrega i jetre. Zaključak: Ispitivane žučne kiseline pokazuju dobre farmakokinetske karakteristike i olakšavaju prolazak makrolida kroz različite ćelijske, Introduction: In the past, bile acids were mostly considered to function in the intestine where they play a role in digestion of fats and mediate absorption of fat-soluble vitamins. Recent studies confirm that bile acids not only facilitate solubilization of fats but behave as signal molecules that interact with various receptors including nuclear receptors and G protein-coupled receptors. As amphipathic molecules they are able to interact with phospholipids of cells membranes and enhance drugs permeation. Thus, bile acids are considered as drug promoters in buccal, ocular, nasal, and transdermal dosage forms. Purpose: The purpose of this research was to investigate bile acids and its oxo derivatives as enhancers in drug permeability. Three research methods to evaluate the characteristics of bile acids and its properties were used. Material and method: The interaction between macrolide antibiotics and bile acids was investigated by NMR chemical-shift titration, self-diffusion measurements and paramagnetic relaxation enhancements. Retention parameters of selected bile acids are acquired by normal-phase thin layer chromatography and evaluated using five different softwares. In vivo experiments were conducted on 126 animals which were divided in 21 groups. Results: Binding bile acids to the micelles is indicated by differences in the chemical shift of the macrolides and line broadening as a consequence of reduced mobility in the micelle. Addition of bile micelles increases the solubility of macrolide antibiotics by a factor of approximately 2–3. Examined correlation analysis confirmed significant dependence between retention factor and intestinal absorption, MDCK epithelial cells, skin permeability, logBB and PPB%. Through the implementation of in vivo experiments it is shown that bile acids promote penetration of macrolides in brain tissue, kidney and liver. Conclusion: Investigated bile acids showed good pharmacokinetic properties and facilitate in macrolides permeat

Pomoćna lekovita sredstva, gde bi spadale i gljive, mogu značajno da umanje rizik od nastanka dijabetesa, da ga odlože ili da umanje njegove posledice. Pregledom savremene literature se uočava potencijal gljive Coprinus comatus da pomogne u regulisanju nivoa glukoze u krvi. S obzirom da su u Srbiji dostupni komercijalni preparati, postojala je potreba za detaljnim ispitivanjem farmakoloških i toksikoloških osobina gljive Coprinus comatus. Cilj ovog istraživanja je bio da se utvrdi: 1) uticaj preparata gljive Coprinus comatus na glikemiju, histološke karakteristike endokrinog pankreasa i parametre toksičnosti kod ispitivanih životinja; 2) protektivno delovanje preparata gljive Coprinus comatus kod životinja izloženih oksidativnom stresu. Vodena suspenzija gljive Coprinus comatus se primenjivala eksperimentalnim životinjama u tri različite doze (0,835 g/kg; 1,67 g/kg i 3,34 g/kg) i tokom tri vremenska intervala svakodnevno (7, 21 i 42 dana). Za ispitivanje uticaja gljive Coprinus comatus na glikemiju životinja korišćeni su adrenalinski test, test oralnog podnošenja glukoze i indukcija trajne hiperglikemije aloksanom. Od biohemijskih parametara u serumu je određivana koncentracija lipida, uree i kreatinina i enzimska aktivnost aspartat i alanin aminotransferaze. Antioksidantna aktivnost gljive Coprinus comatus je određivana i in vitro i in vivo testovima. Nakon žrtvovanja životinja, tkivo jetre i bubrega bojeno je standardnom hematoksilin i eozin metodom, a pankreasno tkivo imunohistohemijskom metodom. Poredeći promenu telesne mase, vidi se da je ona najmanja u grupi životinja koja je dobijala gljivu u najvećoj dozi. Prateći hipoglikemijski efekat gljive, kod 42-dnevnog tretmana je uočena dozna zavisnost. Ako se uzme u obzir histološki izgled Langerhansovih ostrvaca dobija se potvrda rezultata određivanja koncetracije glukoze u krvi životinja sa aloksanskim dijabetesom. Sedmodnevni tretman gljivom C.comatus u dozi od 3,34 g/kg je doveo do značajnog sniženja koncentraci, Natural health products, including mushrooms, can significantly reduce risk of developing diabetes, to postpone it or to reduce its consequences. A contemporary literature indicates to great potential of Coprinus comatus mushroom to help in regulation of blood glucose level. Considering that commercial products are available in Serbia, there was a need for more detailed pharmacological and toxicological investigation of Coprinus comatus mushroom. The aim of research was to determine: 1) influence of Coprinus comatus mushroom on glycaemia, endocrine pancreas histological features and toxicological parameters of experimental animals; 2) protective action of Coprinus comatus mushroom with animals exposed to oxidative stress, Coprinus comatus mushroom water suspension was administered to experimental animals in three different doses (0,835 g/kg; 1,67 g/kg and 3,34 g/kg) and during three time intervals every day (7, 21 and 42 days), Adrenalin test, oral glucose tolerance test and hyperglycaemia induction with alloxan were used to determine Coprinus comatus influence on giycaemia in animals, Also, serum lipid, urea, creatinine concentration and enzymatic activity of aspartate and alanine aminotransferase were determined. The antioxidant activity of Coprinus comatus mushroom was determined by using both in vitro and in vivo tests, After animals' sacrificing, liver and kidney tissues were dyed using standard hematoxylin eosin method, while pancreas tissue using immunohistochemical method. Comparing body weight gain, it can be seen that the smallest change was in group of animals treated with the highest mushroom dose. Dose dependent hypoglycaemic effect was noticed in a 42-days mushroom treatment. Considering histological appearance of Langerhans islets confirmation of blood glucose concentration in alloxan diabetic animals was obtained. Seven days' treatment of C.comatus mushroom in dose of 3,34 g/kg led to a significant total cholesterol decrease in alloxan diabetic an