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Bor je bilo koji četinar roda Pinus koji pripada porodici Pinaceae. U Republici Srbiji nalaze se prirodne i veštačke šume crnog bora Pinus nigra Arnold. Kora bora se vekovima koristila u tradicionalnoj medicini, međutim tek u novije vreme su otkriveni i potvrđeni njeni pozitivni biološki efekti u medicini. Najpoznatiji komercijalni preparat kore bora je piknogenol, standardizovani ekstrakt kore francuskog primorskog bora Pinus pinaster Aiton, koji raste duţ obale jugozapadne Francuske. Pozitivni efekti koje ispoljava piknogenol, kao što su antioksidativno, hipoglikemijsko, hipolipidemijsko delovanje, zasnovani su na njegovom visokom sadržaju fenolnih jedinjenja. Danas, i pored saznanja da je kora bora bogata sekundarnim metabolitima ona najčešće završava kao nusproizvod drvne industrije. Ciljevi ovog rada bili su ispitivanje kvalitativnih i kvantitativnih karakteristika i biohemijskih aktivnosti ekstrakata kore crnog bora Pinus nigra sa Mokre gore i Tare, dobijenih različitim rastvaračima; upoređivanje glikemijskog i lipidnog delovanja ekstrakta kore bora Pinus nigra sa komercijalnim preparatom piknogenol; uticaj ekstrakta kore bora Pinus nigra i piknogenola na delovanje standardnih antidijabetika metformina i gliklazida; kao i uticaj na parametre oksidativnog stresa nakon izlaganja životinja toksičnoj dozi paracetamola. In vitro ispitivanja su uključivala analizu ekstrakata dobijenih različitim rastvaračima. Ukupni sadržaj fenola, tanina, flavonoida i proantocijanidna, kao i ispitivanje antioksidativne aktivnosti kroz pet različitih metoda, određivani su spektrofotometrijski. Vršena je analiza ekstrakata kore bora visokoefikasnom tečnom hromatografijom (HPLC). In vivo ispitivanje je rađeno na 156 albino laboratorijska pacova soja Wistar. Eksperimentalne ţivotinje su tokom 7 dana per os primale ekstrakt kore crnog bora poreklom sa Mokre gore 100 mg/kg, koji je pokazao najbolju aktivnost, piknogenol 50 mg/kg, metformin 100 mg/kg, gliklazid 10 mg/kg, kao i njihove kombinacije. Za ispitivanje uticaja primenjivanih supstanci na glikemiju ţivotinja korišćeni su test oralnog podnošenja glukoze i indukcija trajne hiperglikemije aloksanom. Od biohemijskih parametara u serumu je određivana koncentracija lipida, kao i parametric pokazatelji funkcije bubrega i jetre. Ex vivo ispitivanja uključivala su određivanje intenzitet lipidne peroksidacije i anktivnosti enzima antioksidativne zaštite u homogenatu jetre ispitivanih ţivotinja, nakon primene toksične doze paracetamola. HPLC analizom ekstrakata kore crnog bora utvrđeno je da ekstrakti poreklom sa Mokre gore i Tare u najvećoj meri sadrţe taksifolin, a zatim katehin, njegove derivate, kafenu kiselinu i epikatehin. PotvrĎen je visok antioksidativni kapacitet piknogenola, ali takođe i značajan antioksidativni kapacitet ekstrakata kore crnog bora, sa najboljim rezultatima kod ekstrakta poreklom sa Mokre gore. Sedmodnevni tretman ekstraktom kore bora 100 mg/kg, metforminom 100 mg/kg, gliklazidom 10 mg/kg i piknogenolom 50 mg/kg, kod ţivotinja sa aloksanski izazvanim dijabetesom, doveo je do sniženja glikemije u krvi. Uočeno je povećanje konentracije HDL holesterola i značajno sniženje serumskih triglicerida kod dijabetičnih i normoglikemičnih ţivotinja koje su primale piknogenol, ekstrakta kore bora, gliklazid i metformin u poređenju sa kontrolnom grupom ţivotinja. Zajednička primena ekstrakta kore bora i standardnih antidijabetika značajno je snizila vrednosti AST, ALP i direktni bilirubin u grupi dijabetičnih i normoglikemičnih ţivotinja u odnosu na kontrolnu grupu, čime se ukazuje na potencijalno hepatoprotektivno delovanje ekstrakta kore crnog bora. Oštećenje jetre izazvano toksičnom dozom paracetamola je potvrđeno ispitivanim parametrima, uključujući oksidativni status u homogenatu jetre i histološka ispitivanja. Rezultati našeg istraživanja su pokazali da piknogenol 50 mg/kg, kao i ekstrakt kore crnog bora 100 mg/kg značajno smanjuju nivo MDA u poređenju sa kontrolnom grupom i grupom koja je primala paracetamol. Na osnovu rezultata istraţivanja može se zaključiti da primena piknogenola i ekstrakta kore crnog bora: ublaţava poremećaj homeostaze glukoze, utiče povoljno na lipidni status, značajno potencira antihiperglikemijsko delovanje metformina i hipoglikemijski efekat gliklazida, sprečava poremećaj biohemijskih parametara pokazatelja funkcije jetre i bubrega u serumu ispitivanih životinja i ispoljava značajno in vitro antioksidativno delovanje i sprečava oštećenje jetre laboratorijskih životinja izazvano toksičnom dozom paracetamola., A pine is any conifer in the genus Pinus of the family Pinaceae. In the Republic of Serbia there are natural and artificial forests of black pine Pinus nigra Arnold. Pine bark has been used for centuries in traditional medicine, but only recently its positive biological effects has been revealed and confirmed in medicine. The most famous commercial pine bark product is Pycnogenol, a standardized extract of the French maritime pine bark (Pinus pinaster Aiton), which grows along the coast of southwestern France. The positive effects of Pycnogenol, such as antioxidant, hypoglycemic, hypolipidemic, are based on its high content of phenolic compounds. Nowdays, despite the knowledge that the pine bark is rich in secondary metabolites, it usually ends up as a by-product of the wood industry. The objectives of this dissertation were to investigate the qualitative and quantitative characteristics and biochemical activities of the black pine (Pinus nigra) extracts from Mokra gora and Tara, obtained by different solvents; comparison of glycemic and lipid action of Pinus nigra bark extract with commercial product Pycnogenol; the influence of black pine bark extract and Pycnogenol on the action of standard antidiabetics metformin and gliclazide; as well as the influence on the parameters of oxidative stress in animals exposed to the toxic dose of paracetamol. In vitro analyses included the analysis of extracts obtained with different solvents. The total phenolic, tannin, flavonoid and proanthocyanidin content, as well as the antioxidant activity tests, were determined spectrophotometrically. High-efficiency liquid chromatography (HPLC) was performed in order to determine black pine bark extract content. In vivo analyses was performed on 156 albino Wistar laboratory rats. Experimental animals received for 7 days per os: black pine bark extract obtained from Mokra gora 100 mg/kg, which showed the best activity; Pycnogenol 50 mg/kg; metformin 100 mg/kg; gliclazide 10 mg/kg; and their combinations. An oral glucose tolerance test and the aloxan-induced hyperglycaemia were used to examined the effects of the substances on experimental animals. Biochemical parameters, the lipids concentration and parameters of the kidney and liver function, were determined in animal serum. Ex vivo analyses included determination of lipid peroxidation activity and the activity of antioxidant protection enzymes in liver homogenates of the test animals, after administration of a toxic dose of paracetamol. HPLC analysis of black pine bark extracts obtained from Mokra gora and Tara showed the greatest content of taxifolin, then catechin, and its derivatives, caffeic acid and epicatechin. A high antioxidative capacity of Pycnogenol was confirmed, but also a significant antioxidant capacity of black pine bark extract, with the best results in the extract obtained from Mokra gora. Seven-day treatment in aloxan-induced diabetes animals with 100 mg/kg black pine bark extract, metformin 100 mg/kg, gliclazide 10 mg/kg and Pycnogenol 50 mg/kg led to a decrease of serum glycemic index. There was an increase in the HDL cholesterol concentration and a significant reduction in serum triglycerides in diabetic and normoglycemic animals which received Pycnogenol, black pine bark extract, gliclazide and metformin compared to the control group. Concomitant usage of the black pine bark extract and standard antidiabetics significantly reduced the levels of AST, ALP and direct bilirubin in the group of diabetic and normoglycemic animals compared to the control group, indicating the potential hepatoprotective action of the black pine bark extract. Damage to the liver caused by the toxic dose of paracetamol was confirmed by the liver homogenate oxidative status and histological examination. The results of our study have shown that Pycnogenol 50 mg/kg, as well as 100 mg/kg black pine bark extract significantly reduce the level of MDA in comparison with the control and the paracetamol treated group. Based on the results of the dissertation, it can be concluded that the use of Pycnogenol and black pine bark extract alleviate glucose homeostasis disorder; positively affects the lipid status; significantly increases the antihyperglycemic effect of metformin and the hypoglycemic effect of gliclazide; prevents impairment biochemical parameters of the liver and kidney function in the serum of the experimental animals; significantly exhibits in vitro antioxidant activity and prevents liver damage caused by toxic dose of paracetamol in experimental animals.

Žučne kiseline (ŽK) su strukturno raznoliki molekuli, koji pored uloge koju ostvaruju putem žuči, deluju i kao signalni molekuli i ostvaruju kako endokrina tako i parakrina dejstva. Činjenica da je do sada u terapijske svrhe primenjivana samo ursodeoksiholna kiselina (UDK), posledica je brojnih ograničenja u mogućnosti primene ostalih prirodnih ŽK, i ističe potrebu za otkrivanjem novih sintetskih ŽK i liganda. Cilj istraživanja bio je ispitivanje sintetske 12-monoketoholne kiseline (MK) i prirodne UDK u modelu holestaze i aloksanom izazvanog dijabetesa. Ispitivanja su vršena na pacovima soja Wistar. Analizirana je telesna masa, glikemija, pokazatelji jetrene funkcije (AST; ALT, γ-GT, ukupni i direktni bilirubin), a iz homogenate jetre određen je intenzitet lipidne peroksidacije i aktivnost antioksidativnih enzima (CAT, GSH-Px, GSH-R, GSH-ST). Isečci tkiva jetre su histološki obrađeni i bojeni hematoksilin-eozin metodom i histohemijskim metodama (retikulin, Mallory, Periodic Acid Schiff- Alcian Blue (PAS/AB)). Imunohistohemijski je ispitana proliferacija hepatocita (Ki-67), markeri apoptoze (p53, Bcl-2, Bcl-X, Bax) i ekspresija nuklearnog farnesoid X receptora (FXR). Rezultati istraživanja pokazuju da ispitivane ŽK pomažu očuvanje telesne mase u holestazi i dijabetesu, i značajno snižavaju glikemiju kod dijabetičnih jedinki. Parametri jetrene funkcije u holestazi i dijabetesu su regulisani primenom MK i UDK. Obe ŽK u značajnoj meri smanjuju intenzitet lipidne peroksidacije i pojačavaju enzimsku antioksidativnu odbranu hepatocita u holestazi i dijabetesu. Ekspresija markera apoptoze nije značajno promenjena izazvanjem modela holestaze i dijabetesa, kao ni primenom ispitivanih ŽK. Nasuprot tome, izazivanje holestaze i dijabetesa značajno smanjuje proliferaciju hepatocita, dok primena MK i UDK poništava ovaj efekat i značajno povećava proliferaciju hepatocita. Hiperglikemija u aloksanskom dijabetesu nije dovela do pojačane ekspresije FXR. Izazivanje holestaze kod zdravih i dijabetičnih životinja dovelo je do porasta ekspresije FXR, koja je redukovana primenom MK i UDK. Na osnovu dobijenih rezultata može se zaključiti da sintetska 12-monoketoholna kiselina pokazuje slična hipoglikemijska, hepatoprotektivna i antioksidativna dejstva kao i prirodna ursodeoksiholna kiselina. Bile acids (BAs) are structurally diverse molecules, which have theroles in the digestive system, which are exercised through the bile. Beside those, BAs act as a signaling molecules and achieve endocrine and paracrine effects. In addition to its own metabolism, bile acids modulate the metabolism of lipids and glucose. The fact that so far only ursodeoxycholic acid (UDC) is used for therapeutic purposes, speak clearly about of numerous limitations on the application of other natural BAs, and highlights the need to develop new synthetic Bas and ligands. The aim of this study was to investigate the influence of synthetic 12-monoketocholic acid (MC) and natural bila acid UDC in the model of cholestasis and alloxan-induced diabetes. Tests were performed on male Wistar rats. We analyzed the body mass, glucose, liver function tests (AST, ALT, γ-GT, total and direct bilirubin). Using liver tissue homogenates we determined intensity of lipid peroxidation (by concentration of malondilaldehyde) and the activity of antioxidant enzymes (CAT, GSH-Px, GSH -R, GSH-ST). Liver tissue were histologically processed and stained with hematoxylin-eosin method and histochemical methods (reticulin, Mallory, Periodic Acid Schiff- Alcian Blue (PAS / AB)). Imunohistochemical examination included hepatocyte proliferation (Ki-67), markers of apoptosis (p53, Bcl-2, Bcl-X, Bax), and expression of the nuclear farnesoid X receptor (FXR). Results of the research show that MC prevented decrease in body mass during cholestasis and diabetes, and significantly reduced glycemia in diabetic animals. The liver function tests in cholestasis and diabetes are normalised by MC and UDC aplication. Both BAs significantly reduce lipid peroxidation and enhance enzymatic antioxidant defense of hepatocytes in cholestasis and diabetes. The expression of markers of apoptosis was not significantly changed in models of cholestasis and diabetes, as well as the application of the tested BAs. In contrast, in cholestasis and diabetes model, the proliferation of hepatocytes was significantly reduced, while the use of MC and UDC reversed this effect and significantly increased the proliferation of hepatocytes. Hyperglycemia in alloxan-induced diabetes did not lead to overexpression of FXR. Induction of cholestasis in healthy and diabetic animals resulted in an increase in the expression of FXR, which is reduced by using the MK and the UDC. Based on these results we can conclude that a synthetic 12-monoketocholic acid shows similar hypoglycemic, hepatoprotective and antioxidant effects as natural ursodeoxycholic acid.

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 koncentracije ukupnog holesterola kod životinja sa aloksanskim dijabetesom. Takođe, analizom HDL frakcije holesterola je uočen pozitivan efekat tretmana gljivom C.comatus. Iako je u većini eksperimentalnih grupa tretman gljivom uspeo da spreči porast serumske koncentracije aminotransferaza uzrokovan primenom ugljentetrahlorida, do statistički značajne promene je došlo samo u koncentraciji alanin aminotransferaze grupa 7-dnevnog tretmana. Iako se u literaturi navodi da se kod dijabetičnih životinja, nakon nekoliko nedelja od indukcije dijabetesa, patohistološkim pregledom mogu uočiti promene u glomerulima i mezengijalnom matriksu bubrega, takve nisu uočene niti kod jedne životinje u ovom ogledu. Biohemijski parametri su pokazali da je ipak došlo do oštećenja bubrega kod životinja sa aloksanskim dijabetesom i da je tretman gljivom u određenoj meri uspeo da ublaži ovaj poremećaj. Potvrda visokog antioksidativnog kapaciteta, prvobitno utvrđena DPPH i FRAP testom i određivanjem sadržaja ukupnih fenola, je dobijena i in vivo testovima. Na osnovu rezultata istraživanja može se zaključiti da primena preparata gljive Coprinus comatus: smanjuje prirast telesne mase, ublažava poremećaj homeostaze glukoze, štiti od reaktivnih kiseoničnih vrsta, ubrzava obnovu β ćelija, utiče povoljno na lipidni status i ne izaziva toksične promene u krvi, na jetri i bubrezima ispitivanih životinja., 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 animals. Also, by HDL cholesterol fraction analysis positive effect of C. comatus mushroom treatment was noticed. Mushroom treatment succeeded n preventing serum aminotransferases increase in majority of experimental groups. Only by measuring concentration of alanine aminotransferase in seven days' treatment group of animals, statistically significant change was obtained. Though it was stated in the literature that pathohistological examination can show changes in glomeruls and mesangial matrix in kidneys of diabetic animals, those changes were not found in animals in this experiment. Biochemical parameters showed that, after all, there were still kidney damage in alloxan diabetic animals and :hat mushroom treatment alleviated this disorder in a certain degree. The confirmation of high .lntioxidant capacity, primarily determined by DPPH and FRAP tests and total phenolic content measurement, was reached using in vivo tests, as well, Based on research results it can be concluded that administration of Coprinus comatus mushroom preparation: lowers body weight gain, alleviates glucose homeostasis disorder, protects from reactive oxygen species, accelerates q cells regeneration, affects positively on lipid profile and does not cause toxic changes in blood, liver and kidneys of experimental animals.