Study of the metabolism of 17α-ethinylestradiol by cytochromes P450

Syntetický estrogen 17α-ethinylestradiol (EE2) je hlavní aktivní složkou hormonálních antikoncepčních přípravků. S rostoucí spotřebou hormonální antikoncepce ovšem stoupá riziko zpětného negativního působení EE2 na živé organismy. EE2 je velmi účinný tzv. endokrinní disruptor, což je látka, která svým účinkem napodobuje přirozené hormony. Detailní studium transformace této látky in vivo a in vitro může přispět k porozumění jeho negativních účinků. Předkládaná diplomová práce se proto zabývá studiem metabolismu EE2 u vybraných modelových organismů. Ligninolytická houba Pleurotus ostreatus patří mezi organismy mající slibné biodegradační schopnosti vůči mnoha polutantům. Proto byla studována degradace EE2 v souvislosti s možností odstranění této látky ze životního prostředí. EE2 byl degradován houbou P. ostreatus in vivo za vzniku jednoho hydroxylovaného metabolitu, jehož estrogenní aktivita je předmětem další studie. In vitro studie byly prováděny s mikrosomální frakcí izolovanou z mycelia této houby. Přeměna EE2 pomocí CYP závislých na NADPH nebyla prokázána, ovšem za použití KHP jako kofaktoru byl nalezen metabolit EE2, poukazující na možnou peroxidasovou aktivitu mikrosomálních enzymů. Druhý modelový organismus, laboratorní potkan, se jeví jako vhodný model pro studium metabolismu EE2 v lidském...A synthetic estrogen 17α-ethinylestradiol (EE2) is the main active component of the hormonal contraceptive pills. The rise of consumption of hormonal contraceptives has increased the risk of the back negative effects of EE2 to aquatic organisms. EE2 belongs to the endocrine disruptive compounds known for mimicking natural hormones. A more detailed examination of the transformation of this compound in vivo and in vitro can contribute to a better understanding of its negative effects. This master thesis is therefore devoted to the study of the metabolism of EE2 in two selected model organisms. The ligninolytic fungus Pleurotus ostreatus is the type of fungi with promising biodegradation ability to a lot of pollutants. These properties have led to numerous studies of the degradation potential of P. ostreatus towards EE2, with the possibility of removing this compound from the environment. EE2 has been degraded by the fungus P. ostreatus in vivo resulting in one hydroxylated metabolite, which estrogenic activity is in need for further study. In vitro studies were carried out with a microsomal fraction isolated from the mycelium of this fungus. The conversion of EE2 in vitro via CYPs dependent on NADPH has not been demonstrated, however using KHP as a cofactor, there was one metabolite of EE2 found,...Department of BiochemistryKatedra biochemieFaculty of SciencePřírodovědecká fakult

Antioxidant and antiinflammatory effects of bilirubin.

Bilirubin (BR) byl dlouho považován pouze za odpadní molekulu s potenciálně toxickými účinky zejména na centrální nervový systém. Později bylo zjištěno, že BR působí i cytoprotektivně a mírně zvýšené koncentrace BR vykazují antioxidační, protizánětlivé a imunomodulační účinky, nicméně přesné mechanismy jsou stále předmětem intenzivního výzkumu. Hlavním cílem této práce bylo studium protektivních účinků BR na experimentálních in vivo a in vitro modelech ve vztahu k zánětu a oxidačnímu stresu. Dílčím cílem práce bylo zavedení a validace analytické metody pro stanovení BR a lumirubinu. Potkanům kmene Gunn a příslušným normobilirubinemickým kontrolám byl aplikován lipopolysacharid (LPS, 6 mg/ml, i.p.) nebo fyziologický roztok. Po 12 hodinách byla odebrána krev a vybrané orgány na analýzu markerů zánětu a jaterního poškození. Primární hepatocyty izolované z jater experimentálních potkanů byly ovlivněny BR a TNF-α, buněčné linie HepG2 a SH-SY5Y byly ovlivněny BR a kyselinou chenodeoxycholovou. Hyperbilirubinemičtí potkani měli po aplikaci LPS ve srovnání s normobilirubinemickými potkany signifikantně sníženou zánětlivou odpověď a stupeň jaterního poškození. U potkanů kmene Gunn jsme pozorovali odlišný profil podskupin leukocytů a zároveň snížení exprese mRNA a koncentrace cytokinů IL-6, TNF-α, IL-1β a...For a long time, bilirubin (BR) has been considered a waste molecule with potential toxic effects especially on the central nervous system. Later, it was found that BR exhibited cytoprotective effects and mildly elevated BR levels showed antioxidant, anti-inflammatory and immunomodulatory properties, however, exact mechanisms of the anti-inflammatory actions of BR have not been fully understood yet. The main aim of this study was to assess the protective effects of BR using experimental in vivo and in vitro models in relation to inflammation and oxidative stress. Partial goal was to establish validated analytical method for determination of BR and lumirubin. Gunn and heterozygous rats were treated with lipopolysaccharide (LPS, 6 mg/kg, IP) or vehicle (saline). After 12 hours, blood and organs were collected for analyses of inflammatory and hepatic injury markers. Primary rat hepatocytes were treated with BR and TNF-α, HepG2 and SH-SY5Y cell lines were treated with BR and chenodeoxycholic acid. LPS-treated Gunn rats had a significantly decreased inflammatory response and hepatic injury compared to LPS- treated normobilirubinemic controls. We found different profile of leukocytes subsets and decreased systemic mRNA expressions and concentrations of IL-6, TNF-α, IL-1β and IL-10 in Gunn rats. Hepatic mRNA...Institute of Medical Biochemistry and Laboratory Medicine First Faculty of MedicineÚstav lékařské biochemie a laboratorní diagnostiky 1. LF UK a VFN1. lékařská fakultaFirst Faculty of Medicin

Isolation and characterization of microsomal fraction of fungus Pleurotus ostreatus and its role in the degradation of 17α-ethinylestradiol

Syntetický hormon 17α-ethinylestradiol (EE2), který je součástí hormonálních antikoncepčních pilulek, byl identifikován jako hlavní složka tzv. endokrinně disruptivních látek (EDc). EDc jsou látky, které napodobují svým účinkem přirozené hormony. V posledních letech se jejich množství zejména v podzemních a povrchových vodách značně zvyšuje, což má negativní vliv na hormonální systém zejména vodních organismů. Jelikož není snadné tyto látky z životního prostředí běžnými technikami odstranit, hledají se možnosti jejich biodegradace. Slibné biodegradační schopnosti vůči mnoha polutantům vykazují houby bílé hniloby, které v přírodě rozkládají lignin. Tyto houby disponují širokou škálou nespecifických extracelulárních a intracelulárních enzymů, které ve zmíněných degradacích hrají významnou roli. Tato bakalářská práce byla zaměřena na studium zástupce hub bílé hniloby, houbu Pleurotus ostreatus, a zejména degradační potenciál jeho intracelulárních enzymů při biodegradaci EE2. Nejprve byla ověřena schopnost houby Pleurotus ostreatus degradovat EE2 in vivo. Během 48 hodinové inkubace došlo k odbourání až 95,5 % EE2. Role cytochromů P450 (CYP) při metabolismu EE2 však tímto experimentem nebyla potvrzena, jelikož inhibitor CYP 1-aminobenzotriazol (1-ABT) nesnižoval účinnost degradace. V další fázi...A synthetic hormone 17α-ethinylestradiol (EE2) which is a component of hormonal contraception pills has been identified as a main component of the endocrine-disrupting compounds (EDc). EDc are substances that mimic natural hormones in their action. Recently their amount especially in the groundwater and the surface water has been increased, which results in a negative impact on the hormonal system especially of aquatic organisms. Since it is not easy to replace these substances from the environment by conventional techniques other possibilities of their biodegradation are examined. White rot fungi, which are able to degrade lignin in nature, have promising biodegradation abilities towards many pollutants. These fungi contain a wide range of non-specific extracellular and intracellular enzymes that play an important role in the degradation. This bachelor thesis was targeted on the study of a white rot fungus, Pleurotus ostreatus, and especially on the degradation potential of its intracellular enzymes in the biodegradation of EE2. Initially, the ability of fungi Pleurotus ostreatus to degrade EE2 in vivo was tested. During the 48 hour incubation there was replaced 95,5 % of EE2. However, the role of cytochromes P450 (CYPs) in a metabolism of EE2 was not confirmed in this experiment by reason that an...Katedra biochemieDepartment of BiochemistryPřírodovědecká fakultaFaculty of Scienc

Antioxidant and antiinflammatory effects of bilirubin

Bilirubin (BR) byl dlouho považován pouze za odpadní molekulu s potenciálně toxickými účinky zejména na centrální nervový systém. Později bylo zjištěno, že BR působí i cytoprotektivně a mírně zvýšené koncentrace BR vykazují antioxidační, protizánětlivé a imunomodulační účinky, nicméně přesné mechanismy jsou stále předmětem intenzivního výzkumu. Hlavním cílem této práce bylo studium protektivních účinků BR na experimentálních in vivo a in vitro modelech ve vztahu k zánětu a oxidačnímu stresu. Dílčím cílem práce bylo zavedení a validace analytické metody pro stanovení BR a lumirubinu. Potkanům kmene Gunn a příslušným normobilirubinemickým kontrolám byl aplikován lipopolysacharid (LPS, 6 mg/ml, i.p.) nebo fyziologický roztok. Po 12 hodinách byla odebrána krev a vybrané orgány na analýzu markerů zánětu a jaterního poškození. Primární hepatocyty izolované z jater experimentálních potkanů byly ovlivněny BR a TNF-α, buněčné linie HepG2 a SH-SY5Y byly ovlivněny BR a kyselinou chenodeoxycholovou. Hyperbilirubinemičtí potkani měli po aplikaci LPS ve srovnání s normobilirubinemickými potkany signifikantně sníženou zánětlivou odpověď a stupeň jaterního poškození. U potkanů kmene Gunn jsme pozorovali odlišný profil podskupin leukocytů a zároveň snížení exprese mRNA a koncentrace cytokinů IL-6, TNF-α, IL-1β a...For a long time, bilirubin (BR) has been considered a waste molecule with potential toxic effects especially on the central nervous system. Later, it was found that BR exhibited cytoprotective effects and mildly elevated BR levels showed antioxidant, anti-inflammatory and immunomodulatory properties, however, exact mechanisms of the anti-inflammatory actions of BR have not been fully understood yet. The main aim of this study was to assess the protective effects of BR using experimental in vivo and in vitro models in relation to inflammation and oxidative stress. Partial goal was to establish validated analytical method for determination of BR and lumirubin. Gunn and heterozygous rats were treated with lipopolysaccharide (LPS, 6 mg/kg, IP) or vehicle (saline). After 12 hours, blood and organs were collected for analyses of inflammatory and hepatic injury markers. Primary rat hepatocytes were treated with BR and TNF-α, HepG2 and SH-SY5Y cell lines were treated with BR and chenodeoxycholic acid. LPS-treated Gunn rats had a significantly decreased inflammatory response and hepatic injury compared to LPS- treated normobilirubinemic controls. We found different profile of leukocytes subsets and decreased systemic mRNA expressions and concentrations of IL-6, TNF-α, IL-1β and IL-10 in Gunn rats. Hepatic mRNA...Katedra biochemieDepartment of BiochemistryFaculty of SciencePřírodovědecká fakult

Heme oxygenase-1 may affect cell signalling via modulation of ganglioside composition

Heme oxygenase 1 (Hmox1), a ubiquitous enzyme degrading heme to carbon monoxide, iron, and biliverdin, is one of the cytoprotective enzymes induced in response to a variety of stimuli, including cellular oxidative stress. Gangliosides, sialic acid-containing glycosphingolipids expressed in all cells, are involved in cell recognition, signalling, and membrane stabilization. Their expression is often altered under many pathological and physiological conditions including cell death, proliferation, and differentiation. The aim of this study was to assess the possible role of Hmox1 in ganglioside metabolism in relation to oxidative stress. The content of liver and brain gangliosides, their cellular distribution, and mRNA as well as protein expression of key glycosyltransferases were determined in Hmox1 knockout mice as well as their wild-type littermates. To elucidate the possible underlying mechanisms between Hmox1 and ganglioside metabolism, hepatoblastoma HepG2 and neuroblastoma SH-SY5Y cell lines were used for in vitro experiments. Mice lacking Hmox1 exhibited a significant increase in concentrations of liver and brain gangliosides and in mRNA expression of the key enzymes of ganglioside metabolism. A marked shift of GM1 ganglioside from the subsinusoidal part of the intracellular compartment into sinusoidal membranes of hepatocytes was shown in Hmox1 knockout mice. Induction of oxidative stress by chenodeoxycholic acid in vitro resulted in a significant increase in GM3, GM2, and GD1a gangliosides in SH-SY5Y cells and GM3 and GM2 in the HepG2 cell line. These changes were abolished with administration of bilirubin, a potent antioxidant agent. These observations were closely related to oxidative stress-mediated changes in sialyltransferase expression regulated at least partially through the protein kinase C pathway. We conclude that oxidative stress is an important factor modulating synthesis and distribution of gangliosides in vivo and in vitro which might affect ganglioside signalling in higher organisms

Kolektivní vyjednávání a kolektivní smlouva

Import 20/04/2006Prezenční výpůjčkaVŠB - Technická univerzita Ostrava. Ekonomická fakulta. Katedra (119) práv

Antioxidant and antiinflammatory effects of bilirubin.

For a long time, bilirubin (BR) has been considered a waste molecule with potential toxic effects especially on the central nervous system. Later, it was found that BR exhibited cytoprotective effects and mildly elevated BR levels showed antioxidant, anti-inflammatory and immunomodulatory properties, however, exact mechanisms of the anti-inflammatory actions of BR have not been fully understood yet. The main aim of this study was to assess the protective effects of BR using experimental in vivo and in vitro models in relation to inflammation and oxidative stress. Partial goal was to establish validated analytical method for determination of BR and lumirubin. Gunn and heterozygous rats were treated with lipopolysaccharide (LPS, 6 mg/kg, IP) or vehicle (saline). After 12 hours, blood and organs were collected for analyses of inflammatory and hepatic injury markers. Primary rat hepatocytes were treated with BR and TNF-α, HepG2 and SH-SY5Y cell lines were treated with BR and chenodeoxycholic acid. LPS-treated Gunn rats had a significantly decreased inflammatory response and hepatic injury compared to LPS- treated normobilirubinemic controls. We found different profile of leukocytes subsets and decreased systemic mRNA expressions and concentrations of IL-6, TNF-α, IL-1β and IL-10 in Gunn rats. Hepatic mRNA..

Antioxidant and antiinflammatory effects of bilirubin

For a long time, bilirubin (BR) has been considered a waste molecule with potential toxic effects especially on the central nervous system. Later, it was found that BR exhibited cytoprotective effects and mildly elevated BR levels showed antioxidant, anti-inflammatory and immunomodulatory properties, however, exact mechanisms of the anti-inflammatory actions of BR have not been fully understood yet. The main aim of this study was to assess the protective effects of BR using experimental in vivo and in vitro models in relation to inflammation and oxidative stress. Partial goal was to establish validated analytical method for determination of BR and lumirubin. Gunn and heterozygous rats were treated with lipopolysaccharide (LPS, 6 mg/kg, IP) or vehicle (saline). After 12 hours, blood and organs were collected for analyses of inflammatory and hepatic injury markers. Primary rat hepatocytes were treated with BR and TNF-α, HepG2 and SH-SY5Y cell lines were treated with BR and chenodeoxycholic acid. LPS-treated Gunn rats had a significantly decreased inflammatory response and hepatic injury compared to LPS- treated normobilirubinemic controls. We found different profile of leukocytes subsets and decreased systemic mRNA expressions and concentrations of IL-6, TNF-α, IL-1β and IL-10 in Gunn rats. Hepatic mRNA..

Antioxidant and antiinflammatory effects of bilirubin

For a long time, bilirubin (BR) has been considered a waste molecule with potential toxic effects especially on the central nervous system. Later, it was found that BR exhibited cytoprotective effects and mildly elevated BR levels showed antioxidant, anti-inflammatory and immunomodulatory properties, however, exact mechanisms of the anti-inflammatory actions of BR have not been fully understood yet. The main aim of this study was to assess the protective effects of BR using experimental in vivo and in vitro models in relation to inflammation and oxidative stress. Partial goal was to establish validated analytical method for determination of BR and lumirubin. Gunn and heterozygous rats were treated with lipopolysaccharide (LPS, 6 mg/kg, IP) or vehicle (saline). After 12 hours, blood and organs were collected for analyses of inflammatory and hepatic injury markers. Primary rat hepatocytes were treated with BR and TNF-α, HepG2 and SH-SY5Y cell lines were treated with BR and chenodeoxycholic acid. LPS-treated Gunn rats had a significantly decreased inflammatory response and hepatic injury compared to LPS- treated normobilirubinemic controls. We found different profile of leukocytes subsets and decreased systemic mRNA expressions and concentrations of IL-6, TNF-α, IL-1β and IL-10 in Gunn rats. Hepatic mRNA..

Isolation and characterization of microsomal fraction of fungus Pleurotus ostreatus and its role in the degradation of 17α-ethinylestradiol

A synthetic hormone 17α-ethinylestradiol (EE2) which is a component of hormonal contraception pills has been identified as a main component of the endocrine-disrupting compounds (EDc). EDc are substances that mimic natural hormones in their action. Recently their amount especially in the groundwater and the surface water has been increased, which results in a negative impact on the hormonal system especially of aquatic organisms. Since it is not easy to replace these substances from the environment by conventional techniques other possibilities of their biodegradation are examined. White rot fungi, which are able to degrade lignin in nature, have promising biodegradation abilities towards many pollutants. These fungi contain a wide range of non-specific extracellular and intracellular enzymes that play an important role in the degradation. This bachelor thesis was targeted on the study of a white rot fungus, Pleurotus ostreatus, and especially on the degradation potential of its intracellular enzymes in the biodegradation of EE2. Initially, the ability of fungi Pleurotus ostreatus to degrade EE2 in vivo was tested. During the 48 hour incubation there was replaced 95,5 % of EE2. However, the role of cytochromes P450 (CYPs) in a metabolism of EE2 was not confirmed in this experiment by reason that an..