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Diimide reduction and reduction of tri- and tetrapyridylporphyrins with tin (II) chloride
No full textFotodinamička terapija (PDT) je jedan od suvremenijih pristupa u liječenju tumora te je još uvijek u razvoju. Za PDT su potrebne tri komponente: fotosenzibilizator (PS), izvor svjetlosti i molekularni kisik. Uspješnost PDT-a ovisi o svojstvima PS-a, a trenutno su najčešće korišteni tetrapirolni makrocikli: porfirini, klorini i bakterioklorini. Klorini i bakterioklorini imaju jači apsorpcijski pik u crvenom području (~ 650 - 750 nm) od porfirina (~ 630 nm) te ih upravo to fizikalno svojstvo čini boljim fotosenzibilizatorima zato što svjetlost te valne duljine (~ 650 - 750 nm) dublje prodire u tkivo. Cilj ovog diplomskog bio je ispitati metode dobivanja klorina iz tetra- i tripiridilporfirina te su napravljeni razni pokušaji modifikacije diimidne redukcije i redukcije s kositar(II) kloridom (SnCl2). Reakcije su rađene na tri različita porfirina: 5,10,15,20-tetrakis (3-piridil)porfirin (1), 5-(4-acetamidofenil)-10,15,20-tris(3-piridil) porfirin (2) i 5-(4-aminofenil)- 10,15,20-tris(3-piridil)porfirin (3). Dobiveni rezultati pokazali su da je redukcija porfirina s SnCl2 regioselektivna te u reakciji s porfirinom 2 daje gotovo isključivo klorin 9. U diimidnoj redukciji nastaje smjesa produkata (početni porfirin, klorin, bakterioklorin, izobakterioklorin) koju je teško odvojiti te se u ovom slučaju najbolje pokazala oksidacija produkata diimidne redukcije do klorina. Oksidacijom bakterioklorina 8 nastaje klorin 10 s primjesama nečistoća. U budućim ispitivanjima trebalo bi optimizirati metode odvajanja te bi se u redukciji s SnCl2 trebalo ispitati bi li nastalo više klorina kada bi se dodalo više ekvivalenata SnCl2.Photodynamic therapy (PDT) is one of the modern approaches in the treatment of tumors and is still in development. PDT requires three components: a photosensitizer (PS), a light source and molecular oxygen. The success of PDT depends on the properties of PS and currently the most commonly used PSs are tetrapyrrole macrocycles: porphyrins, chlorins and
bacteriochlorins. Chlorins and bacteriochlorins have a stronger absorption peak in the red region (~ 650 - 750 nm) than porphyrins (~ 630 nm) and it is this physical property that makes them better photosensitizers because
light of this wavelength (~ 650 - 750 nm) penetrates deeper into the tissue. The aim of this master thesis was to test the methods of obtaining chlorin from tetra- and tripyridylporphyrins and various attempts were made to modify the diimide reduction and reduction with tin (II) chloride (SnCl2). Reactions were performed on three different porphyrins:
5,10,15,20-tetrakis(3-pyridyl) porphyrin (1), 5-(4-acetamidophenyl)-10,15,20-tris(3-pyridyl) porphyrin (2) and 5-(4-aminophenyl)-10,15,20- tris(3-pyridyl) porphyrin (3). The obtained results showed that the reduction of porphyrin with
SnCl2 is regioselective and in the reaction with porphyrin 2 gives almost exclusively chlorin 9. In diimide reduction a mixture of products is formed (initial porphyrin, chlorin, bacteriochlorin, isobacteriochlorin) which is difficult to separate and in this case it has been shown that oxidation of diimide reduction products to chlorin is the best option. Oxidation of
bacteriochlorin 8 produces chlorin 10 with impurities. In future studies, separation methods should be optimized and, in
reduction with SnCl2, it should be examined whether more chlorin would be formed when more SnCl2 equivalents are added
Crijevno-moždana os u depresivno-anksioznim poremećajima
No full textDepresivno-anksiozni poremećaji sve su češća pojavnost u današnjim društveno-ekonomskim okolnostima te je proučavanje mehanizama koji uvjetuju zabrinjavajuća ponašanja sada posebno relevantan. U zadnja dva desetljeća mnogo je pažnje usmjereno na razotkrivanje crijevno-moždane osi kao modulatora raznih patofizioloških procesa povezanih s mentalnim i drugim oboljenjima. Naime, radi se o dvosmjernoj, direktnoj i indirektnoj, komunikaciji između mozga i crijevne mikrobiote koja uključuje kemijske (neuro)transmitere, aferentne i eferentne puteve autonomnog živčanog sustava (ANS), neuroendokrini sustav posebno u vidu regulatorne HPA-osi (os hipotalamus-hipofiza-nadbubrežna žlijezda), odrednice imunog sustava i različite metaboličke puteve. Za dokazivanje povezanosti crijevne mikrobiote i mentalnih oboljenja bili su neophodni mišji modeli koji su pridonijeli saznanjima o utjecaju kroničnog i akutnog stresa, antibiotika, spolno-ovisnih razlika, vagusnog živca i mnogih drugih faktora, na crijevne bakterije i, posljedično, na mozak. Istraživanjima je otkriveno da oboljeli od depresije i anksioznosti imaju značajne razlike u konstituciji i funkciji crijevne mikrobiote od zdravih kontrola. U oboljelih je evidentirana disregulacija HPA-osi, abnormalna razina kortizola, poremećen serotonergički sustav djelomično kao posljedica neuravnoteženog kinurenskog puta (KP) čiji metaboliti imaju neurotoksični potencijal, povećana neuroimflamacija proupalnim citokinima itd. Postoje jaki argumenti kako su svi prethodno navedeni čimbenici potpuno ili djelomično modulirani crijevnom mikrobiotom ili disbiozom iste. Istraživanja ovog područja, ne samo da su dala osnovu za intenzivno ciljanje mikrobne stimulacije kao terapijskog pristupa mentalnim bolestima, već su omogućila nastavak destigmatizacije mentalnih bolesti za koje je sada i više nego jasno da nemaju samo psihološki, već i fiziološki profil
Platelets - cells with many functions
No full textPlatelets are a multifunctional cell with roles in homeostasis, heamostatic and non-heamostatic events. They contribute and are essential to the process of blood clotting. Platelets are great player in the onset of thrombosis. Platelets also play a less known role in immunity, neuroinflammation and tumour biology. These blood cells pose as important targets in the treatment of various cardiovascular and inflammatory diseases, as well as in the onset of cancer. Some antiplatelet therapies are already in use, however the majority of them is still being researched as they hold great potential as future treatment methods
Human genome editing: from methodology to ethical aspect
No full textPojam editiranje gena odnosi se na izmjenu željenog nukleotidnog slijeda DNA molekule. Otkriće novih, revolucionarnih metoda genetičkog editiranja, od kojih su trenutno najpopularnije i najkorištenije nukleaze cinkovih prstiju (engl. zinc finger nucleases, ZFN), efektorske nukleaze nalik aktivatoru transkripcije (engl. transcription activator-like effector nucleases, TALEN) te niz međusobno razdvojenih kratkih, klasteriranih, palindromskih ponavljanja povezanih s proteinom 9 (engl. clustered regularly interspaced short palindromic repeat – CRISPR– associated protein 9, CRISPR-Cas9), uspostavilo je naprednu generaciju alata koji imaju ključnu ulogu u molekularnoj biologiji, ali i nizu drugih biotehnoloških disciplina. Međutim, vjerojatno najveći potencijal za primjenu metoda editiranja genoma čovjeka je u medicini zbog pretpostavke da se promjenama u specifičnim genima mogu suzbiti brojne bolesti i poremećaji koji se još uvijek smatraju neizlječivima na razini uzroka. U tijeku je razvoj novih terapijskih mogućnosti, a jedna od trenutno klinički primjenjivih terapija je stanična imunoterapija T limfocitima koji su genetički modificirani kimernim antigenskim receptorom (engl. chimeric antigen receptor, CAR), za liječenje novotvorina. U ovom završnom radu, osim opisane metodologije alata za editiranje genoma te perspektivnih pretkliničkih i kliničkih ispitivanja za otkriće novih strategija liječenja bolesti, razmatraju se i etički aspekti editiranja genoma, kao i opisane smjernice za njegovu primjenu, koja je za sada moguća isključivo na somatskim stanicama. Kako bi se dostigla pouzdana razina učinkovitosti i sigurnosti metoda editiranja gena, potrebno je daljnje usavršavanje u odabiru adekvatnih metoda dostave programabilnih nukleaza u stanice te ustrajanje u razvoju pouzdanijeg in vivo editiranja, a ponajviše u donošenju etičkih i pravnih okvira za razumno, svrsishodno i nemanipulativno korištenje editiranja genoma.The term gene editing refers to the modification of the desired nucleotide sequence of a DNA molecule. Discovery of new, revolutionary methods of genetic editing, of which the most popular and most used are zinc finger nucleases (ZFN), transcription activator-like effector nucleases (TALEN) and clustered regularly interspaced short palindromic repeat – CRISPR–associated protein 9, (CRISPR-Cas9), has established an advanced generation of tools that play a key role in molecular biology, as well as a number of other biotechnological disciplines. However, probably the greatest potential for the application of human genome editing methods is medicine due to the assumption that changes in specific genes can suppress a number of diseases and disorders that are still considered incurable at the cause level. New therapeutic options are being developed, and one of the currently clinically applicable therapies is cellular immunotherapy that uses T lymphocytes that are genetically modified by the chimeric antigen receptor (CAR), for the treatment of neoplasms. In this undergraduate thesis, in addition to the described methodology of genome editing tools and perspective preclinical and clinical trials for the discovery of new treatment strategies, the ethical aspects of genome editing are discussed, as well as the described guidelines for its application, which is currently possible only on somatic cells. In order to achieve a reliable level of efficiency and safety of the gene editing methods, further improvement in the selection of adequate methods for delivering programmable endonucleases to cells is needed, but also persistence in the development of more reliable in vivo editing and in adopting ethical and legal frameworks for the reasonable, purposeful and non-manipulative use of genome editing
Adverse effects of oral contraceptives reported to the Agency for Medicinal products and Medicinal devices
No full textOralna hormonska kontracepcija (OHK) jedna je od najučinkovitijih reverzibilnih metoda kontracepcije. OHK sprječava trudnoću, ali utječe i na druge organe i organske sustave. U ovom istraživanju obrađene su nuspojave hormonskih oralnih kontraceptiva za sistemsku primjenu (ATK G03A) koje je Hrvatska agencija za lijekove i medicinske proizvode (HALMED) zaprimila u razdoblju od 11. lipnja 1993. do 2. veljače 2021. godine. Analizirano je 515 prijava sumnji na nuspojave lijekova skupine G03A, a podaci su obrađeni prema dobi i spolu pacijenta, ozbiljnosti, ishodu, prijavitelju, pripadnosti nuspojava prema klasifikaciji organskih sustava Medicinskog rječnika za regulatorne poslove (MedDRA) te djelatnoj tvari. Također, analizirana je i učestalost nuspojava hormonskih oralnih kontraceptiva u ukupnom broju prijavljenih nuspojava. Od ukupno 515 analiziranih nuspojava lijekova, najveći se broj odnosio na pacijente u dobnoj skupini od 18 do 30 godina (38,45 %). Najviše su nuspojava prijavili liječnici (41,75 %). Najveći broj nuspojava nije bio ozbiljan (63,69 %). Prema djelatnoj tvari, najveći je broj nuspojava prijavljen za kombinaciju drospirenona i etinilestradiola (28,36 %), kombinaciju gestodena i etinilestradiola (16,57 %) te ulipristal (11,05 %). Najveći broj nuspojava pripada organskim sustavima (SOC) prema MedDRA-i Poremećaji reproduktivnog sustava i dojki (14,49 %) te SOC Opći poremećaji i reakcije na mjestu primjene (11,98 %). Dvije su najučestalije prijavljene nuspojave lijekova glavobolja (4,45 %) i mučnina (3,97 %). Usporedbom s europskom (EudraVigilance) i svjetskom (VigiAccess) bazom podataka nuspojava lijekova, utvrđeno je podudaranje u većini obrađenih podataka. Iako je u tim bazama podataka bol navedena kao najčešća nuspojava, u ovom je istraživanju utvrđeno da na nacionalnoj razini nije česta.Oral hormonal contraception (OHC) is one of the most effective reversible method of contraception. OHC prevents pregnancy, but also effects other organs and organ systems. The purpose of this thesis is to analyze the suspected adverse reactions of oral hormonal contraceptives for systemic use (ATK G03A) reported to the Agency for Medicinal Products and Medical Devices of Croatia (HALMED) in the period from June 11, 1993 to February 2, 2021. In total, 515 suspected adverse drug reactions from G03A group were analyzed and data were proccesed according to the patient's age and gender, seriousness, outcome, reporter, affiliation of adverse reactions according to the Medical Dictionary of Regulatory Affairs (MedDRA) organic system classification and active substance. Also, the frequency of side effects of oral hormonal contraceptives in the total number of reported side effects was analyzed. Most adverse drug reactions were reported by doctors (41,75 %). The largest number of adverse drug reactions was not serious (63,69 %). According to the active substance, the highest number of adverse reactions was reported for the combination of drospirenone and ethinlyestradiol (28,36 %), the combination of gestodene and ethinylestradiol (16,57 %) and ulipristal (11,05 %). The largest number of adverse drug reactions belongs to System organ class (SOC) Reproductive system and breast disorder (14,49 %) and SOC General disorders and administration site conditions (11,98 %). Two most common adverse reactions were headache (4,45 %) and nausea (3,97 %). Comparison with European (EudraVigilance) and global (VigiAccess) database of adverse drug reactions, a match was found in most of the processed data. Although pain is listed as the most common adverse reaction in these databases, this study found that it is not common nationally
Transcription factor c-Myc as a target for new breast cancer therapy
No full textoai:repository.biotech.uniri.hr:biotechri_643Transkripcijski faktori imaju važnu ulogu u normalnom funkcioniranju stanice, utječu na stanični ciklus, metabolizam i druge stanične procese. No, njihova amplifikacija i deregulacija može dovesti do razvoja povoljnih uvjeta za nekontroliran rast i razvoj stanica raka. S obzirom na to da je učestalost razvoja kemorezistencije na postojeću terapiju u brojnim malignim bolestima sve veća te su postojeći lijekovi izrazito citotoksični, potreban je razvoj novih strategija za njihovo liječenje. Da bi se odredio učinak inhibicije c-Myc kao monoterapije te kombinirane terapije s postojećim lijekovima u liječenju karcinoma dojke, pretražila sam znanstvenu literaturu pomoću Pubmed i Mendeley tražilice znanstvenih radova. Poseban je naglasak stavljen na molekularnu kompleksnost karcinoma dojke, koja otežava odabir ispravne terapije, te učinke djelovanja c-Myc transkripcijskog faktora u svakom pojedinom tipu toga karcinoma i njegovom doprinosu u razvoju rezistencije na lijekove. Najbolji učinak inhibicije c-Myc-a pokazao se u trostruko-negativnom tipu raka dojke (engl.Triple-negative breast cancer, TNBC) s obzirom da je kod tog tipa karcinoma dojke, najčešća amplifikacija c-Myc-a. U ovome tipu raka dojke inhibitori c-Myc-a pokazali su se učinkovitima u senzibilizaciji TNBC stanica na postojeće kemoterapeutike. Rezultati istraživanja djelovanja inhibitora c-Myc-a pokazali su značajan potencijal za upotrebu u budućnosti, ali i farmakološke nedostatke koje je potrebno modificirati kako bi se povećalo terapijsku učinkovitost. Potrebno je provesti daljnja in vivo istraživanja kako bi se odredio potpuni terapeutski potencijal, ali i toksičnost inhibicije transkripcijskih faktora u zdravom tkivu.Transcription factors have important roles in normal cell functioning by
affecting the cell cycle, metabolism and other cellular processes. However,
their amplification and deregulation may lead to developing favorable
conditions for abnormal growth and development of cancer cells. Given the
frequency of chemoresistance development to existing therapy of many
malignancies and their cytotoxicity, new strategies for their treatment are
needed. To determine the effect of targeting transcription factors for breast
cancer therapy, I searched and studied the scientific literature via Mendeley
and Pubmed searching engines. Special stress was put on molecular
complexity of breast cancer, which makes it difficult to choose the right
therapy, and the effects of c-Myc in breast cancer subtypes. The c-Myc
inhibition was shown to be the most effective in TNBC breast cancer. The
reason behind that is the fact that c-Myc is mostly amplified in this breast
cancer subtype. In this breast cancer subtype, c-Myc inhibitors have shown to
be effective in sensitizing TNBC cells to existing chemotherapeutics. Because
of all the effects that c-Myc has in breast cancer subtypes, it represents
potential therapeutic target. The results of c-Myc inhibitor activity studies
showed its significant potential for the future terapeutic use. To determine full
therapeutic potential and cytotoxicity of c-Myc inhibitors, more in vivo studies
are needed
Quantification of expression of markers of the central nervous system of postantal opossums (Monodelphis domestica)
No full textFunkcije moždanog korteksa u središnjem živčanom sustavu (SŽS) direktno su povezane sa njegovom staničnom kompozicijom, čije osnove su utvrđene tijekom ranog razvoja. Razumijevanje brojčane distribucije neurona i ostalih
stanica korteksa od kritične je važnosti jer patofiziološkim procesom neurodegeneracije taj se broj progresivno reducira. Osim toga, tijekom regeneracije tkiva aktiviraju se stanični procesi koji su identični ili vrlo slični razvojnim procesima. Jedinstveni model za istraživanje neuroregeneracije u sisavcima je oposum, koji pokazuje sposobnost regeneracije SŽS-a kroz
embrionalni razvoj sve do drugog postantalnog tjedna. Postnatalni razvoj korteksa oposuma nije u potpunosti istražen. Ukupan podatak o broju neurona i „ne-neuronalnih“ stanica za prva dva postnatalna tjedna (<P18) nije još objavljen u literaturi, a za dob stariju od P18 su dostupni samo podaci za ukupan broj svih stanica i neurona. Pomoću metode izotropnog frakcionatora (IFR) i fluorescentne mikroskopije proveli smo kvantifikaciju stanica korteksa u oposumima postnatalnih dana (P) 6, 18, 34 i 35. Pokazali smo kako apsolutni broj svih stanica korteksa, uključujući i broj neurona raste kroz postnatalni period, te broj „ne-neuronalnih“ stanica naglo raste od P18 do P34, što nam je ukazalo na kraj neurogeneze i početak gliogeneze. Koristili smo markere NeuN, SOX2 i Ki-67 kako bi identificirali i kvantificirali diferencirane neurone te također progenitorske i proliferativne stanice korteksa oposuma u prvom postnatalnom tjednu (P6). Kvantifikacija ekspresijskih markera ukazala je na mogućnost da u korteksu P6 oposuma postoji populacija stanica nezrelih neurona kod kojih dolazi do kasnijeg utišavanja progenitorskih staničnih karakteristika.Functions of the cerebral cortex in the central nervous system (CNS) are directly related to its cellular composition, the basics of which are established during early development. Understanding the numerical distribution of neurons and other cortical cells is crucial because during pathophysiological processes of neurodegeneration the number of these cells decreases progressively. In addition, cellular processes that are identical or very similar to developmental processes are activated during tissue regeneration. A unique model for the study of neuroregeneration in mammals is the
opossum, which shows the ability to regenerate the CNS through embryonic development until the second postnatal week. The postnatal development of the opossum cortex has not been fully investigated. Data on the total
number of neurons and “non-neuronal” cells for the first two postnatal weeks (<P18) have not yet been published, and for the ages older than P18, the only available data include the total number of all cells and neurons. Using
the isotropic fractionator (IFR) method and fluorescence microscopy, we quantified cortical cells in opossums of postnatal days (P) 6, 18, 34, and 35. We showed that the absolute number of all cortical cells, including the number of neurons, increased through the postnatal period and that "nonneuronal" cells increase dramatically from P18 to P34, which indicated the end of neurogenesis and the beginning of gliogenesis. We used markers NeuN, SOX2 and Ki-67 to identify and quantify differentiated neurons as well as progenitor and proliferative cells of the opossum cortex in the first
postnatal week (P6). Quantification of expression markers indicated the possibility of an immature neuron cells population in the P6 opossum cortex whose progenitor cell characteristics are subsequently silenced
Hematologic disorders caused by ribosomopathies
No full textRibosomopatije su skupina bolesti koje su uzrokovane abnormalnostima u strukturi ili funkciji ribosoma i njegovih komponenti te gena koji su uključeni u biogenezu ribosoma. Karakteristični fenotipovi koje uzrokuju kod pojedinca uključuju abnormalnosti u rastu i razvoju, zatajenje koštane srži i ostale brojne hematološke poremećaje te povećan rizik od razvitka raka. Prva opisana ribosomopatija i ona koja se smatra predstavnikom ove skupine bolesti je Diamond-Blackfan anemija (DBA). Ostale poznate ribosomopatije su 5q-sindrom, Schwachman-Diamond sindrom (SDS), kongenitalna diskeratoza (DC), Treacher Collins sindrom (TCS) i hipoplazija hrskavice i dlake (CHH). Ovaj će rad opisati i raspraviti patogenezu bolesti, najznačajnije karakteristike svake od ovih bolesti s fokusom na hematološke poremećaje te molekularne mehanizme koji uzrokuju ove poremećaje. Najčešći hematološki poremećaji koji su uzrokovani ribosomopatijama su makrocitna anemija, nepravilna hematopoeza, i kod nekih neutropenija i tromocitopenija. Nadalje, rad će se fokusirati na posljedice koje uzrokuju ove bolesti te moguće načine liječenja ribosomopatija.Ribosomopathies are a group of diseases caused by abnormalities in the structure or function of the ribosome and its components and genes involved in the biogenesis of the ribosome. Characteristic phenotypes they cause in an individual include abnormalities in growth and development, bone marrow failiure and a number of other hematological disorders as well as an increased risk of developing cancer. The first ribosomopathy described and one considered to be representative of this group of diseases is Diamond-Blackfan anemia (DBA). Other known ribosomopathies are 5q-syndrome, Shwachman-Diamond syndrome (SDS), dyskeratosis congenita (DC), Treacher Collins syndrome (TCS) and cartilage hair hypoplasia (CHH). This thesis will describe and discuss the pathogenesis of the disease, the most significant features of each of these disorders with a focus on the hematological disorders and molecular mechanisms that cause these disorders. The most common hematological disorders caused by ribosomopathies are macrocytic anemia, irregular hematopoiesis, and in some cases neutropenia and thromocytopenia. Furthermore, the paper will focus on the consequences of these diseases and possible treatments for ribosomopathies
Chemical and biological evaluation of organic extracts of Adriatic sea ascidian, Phallusia mammillata
No full textPhallusia mammillata (Cuvier, 1815) je plaštenjak koji se prilagodio ekstremnim uvjetima morskog okoliša proizvodnjom bioaktivnih sekundarnih metabolita koji štite organizam od predatora te pomažu u lovu i borbi za moguće stanište. Morski sekundarni metaboliti, zbog svojih jedinstvenih kemijskih struktura te širokog spektra bioloških aktivnosti, mogu biti izvor novih kandidata lijekova. Većina istraživanja koja su se do sada provela na P. mammillata, proučavala su osnovne razvojne procese, no nema puno radova o biološkim aktivnostima ekstrakata plaštenjaka ili njegovih sekundarnih metabolita. Zato smo u sklopu ovog diplomskog rada proveli evaluaciju biološkog potencijala krutih organskih ekstrakata P. mammillata, in vitro. Ekstrakcija organizma je provedena pomoću pet otapala različitih polarnosti: petroletera, diklormetana, etanola, metanola i acetonitrila kako bi se odredilo najprikladnije otapalo za daljnju ekstrakciju plaštenjaka. Optimizacijom ekstrakcije utvrđeno je da je petroleter najprikladnije nepolarno otapalo, a etanol najprikladnije polarno otapalo obzirom na iskorištenja ekstrakcija. Antioksidativna aktivnost krutih organskih ekstrakata P. mammillata je ispitana pomoću ABTS i DPPH eseja. Antiproliferativni i citotoksični učinci ekstrakata, izraženi kao IC50 i LC50 vrijednosti, redom, su procijenjeni pomoću MTT eseja na tumorskim staničnim linijama karcinoma debelog crijeva (HCT116), duktalnog adenokarcinoma gušterače (CFPAC-1), metastatskog tumora dojke (MCF-7), hepatocelularnog karcinoma jetre (HepG2) te netransformiranim ljudskim fibroblastima (HFF-1). Alkoholni i acetonitrilni ekstrakti su pokazali značajnu ABTS antiradikalnu aktivnost. Značajna DPPH antiradikalna aktivnost nije opažena kod nijednog ekstrakta P. mammillata. Petroleterski ekstrakt je jedini pokazao značajan antiproliferativan i citotoksičan učinak na tumorskim staničnim linijama. Proveden je kvalitativni kemijski probir kako bi se utvrdilo koje skupine metabolita mogu biti odgovorne za ispitane biološke aktivnosti. Svi ekstrakti P. mammillata su pokazali prisutnost fenola i alkaloida. Terpenoidi, glikozidi i steroidi su jedino bili uočeni u ekstraktima petroletera i acetonitrila dok su saponini jedino bili prisutni u ekstraktu acetonitrila.Phallusia mammillata (Cuvier, 1815) is a tunicate which has adapted to the harsh marine environment by production of the secondary bioactive metabolites that provide protection from predators, aid in hunting process and defend their territory against invading competitors. Because of their unique chemical structures and diverse biological activities, marine secondary metabolites can be used to design and develop new potentially useful therapeutic agents. Majority of studies using P. mammillata investigated its basic development processes, but biological activities of tunicate extracts or its secondary metabolites have not been thoroughly described. Thus, the evaluation of in vitro biological potential of crude organic extracts of tunicate P. mammillata was conducted. To determine the most suitable organic solvent for the extraction process, the organism was extracted by using five solvents of different polarity: petroleum ether, dichloromethane, ethanol, methanol and acetonitrile. Petroleum ether and ethanol were the most suitable nonpolar and polar solvents, respectively, based on extraction yields. Antioxidant activity of P. mammillata crude organic extracts was tested by ABTS and DPPH assays. Antiproliferative and cytotoxic activities, expressed as IC50 and LC50 values, respectively, were evaluated by MTT assay by using following tumor cell lines: colorectal carcinoma (HCT116), ductal pancreatic adenocarcinoma (CFPAC-1), metastatic breast cancer (MCF7), hepatocellular carcinoma (HepG2) as well as non-transformed skin fibroblasts (HFF). Alcoholic and acetonitrile extracts showed significant ABTS scavenging activity. Significant DPPH scavenging activity was not observed in any of the organic extracts. Only petroleum ether extract demonstrated significant antiproliferative and cytotoxic activity against tumor cell lines. To evaluate which natural products classes may be responsible for observed biological activities, the presence of bioactive metabolites in P. mammillata organic extracts was evaluated by specific and qualitative colorimetric tests. Qualitative chemical screening of organic extracts revealed the presence of phenolic compounds and alkaloids in each tested sample. Terpenoids, sterols and glycosides were present in petroleum ether and in acetonitrile extract, while absent in the rest of samples. Saponins were detected only in acetonitrile extract
Development of 3D-QSAR models for Type I Src kinase inhibitors
No full textZNAČAJ: Src kinaza je tirozin kinaza koja sudjeluje u prijenosu signala povezanih s brojnim staničnim procesima, kao što su proliferacija, diferencijacija, ili adhezija. Src kinaza poželjna je terapijska meta jer ima prekomjernu ekspresiju, visoku aktivnost i jak utjecaj na razvoj metastaza u raznovrsnim tipovima karcinomima.
METODE: Razvili smo kvantitativne i kvalitativne 3D-QSAR modele koji se temelje na molekulskim poljima koristeći literaturno dostupne Src inhibitore tipa I.
REZULTATI: Razvijena su 4 odvojena modela za 4 klase strukturno sličnih analoga; PP2 analozi, Dasatinib analozi, Saracatinib analozi, Zajednički skup, od kojih se model za skup Saracatinib analoga pokazao kao najbolji model visoke točnosti i stabilnosti s prihvatljivom prediktivnom moći (PLS: q2=0.63; SVM: q2=0.60) i dobrim koeficijentom korelacije (PLS: r2=0.92, rtes2=0.85; SVM: r2=0.95, rtest2=0.28). Dodatno, cilj je bio usporediti pristup temeljen na ligandima (engl. LBDD, ligandbased drug design) s pristupom temeljenim na strukturi (engl. SBDD, structure-based drug design). Spojevi korišteni za izgradnju 3D-QSAR modela uklopljeni su u DFG-"in" konformaciju Src kinaze koristeći literaturno dostupne kristalne strukture, te su uklopljene komplekse minimizirani MM-GBSA metodom. Niska korelacija (r=0.48) eksperimentalnih aktivnosti i Gibbsove energije interakcije dobivene MMGBSA metodom, ukazuje kako pristup temeljen na strukturi ne poboljšava predviđanje aktivnosti Src inhibitora u odnosu na pristup temeljen na ligandu. U posljednjem koraku dobiveni rezultati su uspoređeni s prethodno objavljenim studijama te je pokazano da je predstavljeni model za saracatinib skup podataka bolji od do sada objavljenih studija te da MM-GBSA metoda nije korisna za efikasno predviđanje aktivnosti.
ZAKLJUČAK: Opisali smo odnose između strukture i aktivnosti za tip I inhibitore Src kinaza koristeći robusnije i pouzdanije modele s boljom prediktivnom moći za dizajn, filtriranje i prioritiziranje virtualnih biblioteka potencijalnih SRC inhibitora. Predstavljeni rezultati mogu se korsititi za planiranje sinteze novih i aktivnijih inhibitora.BACKGROUND: Src kinase is a tyrosine kinase that participates in the transmission of signals associated with numerous cellular processes such as proliferation, differentiation, or adhesion. Src is a desirable therapeutic target because it is overexpressed and highly active in various cancers, and it influences the development of metastasis as well.
METHODS: Field-based quantitative and qualitative 3D-QSAR models were developed for literature-available Type I Src inhibitors.
RESULTS: Four separate models have been developed for 4 classes of structurally similar analogues; PP2 analogues, Dasatinib analogues, Saracatinib, analogues, Common set, of which the model for the Saracatinib analogue set proved to be the best model of high accuracy and stability with acceptable predictive power (PLS: q2=0.63; SVM: q2=0.60), and good correlation coefficient (PLS: r2=0.92, rtes2=0.85; SVM: r2=0.95, rtest2=0.28). Additionally, the aim was to compare the ligand based approach (LBDD) with the structure-based drug design (SBDD). Compounds used to build the 3D-QSAR model were incorporated into the DFG-"in" conformation of Src kinase literature-available crystal structures, and the incorporated complexes were minimized by the MM-GBSA method. The low correlation (r=0.48) of the experimental activities and the Gibbs interaction energy obtained by the MM-GBSA method indicates that the structure-based approach does not improve the prediction of Src inhibitor activity compared to the ligand-based approach. Finally, the obtained results were compared with previously published studies and we concluded that the saracatinib data set is better than the previously published studies, and that the MM-GBSA method is not useful for an efficient prediction of activity.
CONCLUSION: We described the structure-activity relationships for type I Src kinase inhibitors using more robust and reliable models with better predictive capability; design; filtering and prioritization of virtual libraries of potential Src inhibitors. The presented results can be used to plan the synthesis of new and more active inhibitors