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Wyszukujesz frazę "cytochrome p-450" wg kryterium: Temat


Tytuł:
Toxicological and cytophysiological aspects of lanthanides action.
Autorzy:
Pałasz, Artur
Czekaj, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/1044234.pdf
Data publikacji:
2000
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
gadolinium
cytochrome P450.
calcium
lanthanides
metals
Opis:
Lanthanides, also called rare-earth elements, are an interesting group of 15 chemically active, mainly trivalent, f-electronic, silvery-white metals. In fact, lanthanides are not as rare as the name implies, except for promethium, a radioactive artificial element not found in nature. The mean concentrations of lanthanides in the earth's crust are comparable to those of life-important elements like iodine, cobalt and selenium. Many lanthanide compounds show particular magnetic, catalytic and optic properties, and that is why their technical applications are so extensive. Numerous industrial sources enable lanthanides to penetrate into the human body and therefore detailed toxicological studies of these metals are necessary. In the liver, gadolinium selectively inhibits secretion by Kupffer cells and it decreases cytochrome P450 activity in hepatocytes, thereby protecting liver cells against toxic products of xenobiotic biotransformation. Praseodymium ion (Pr3+) produces the same protective effect in liver tissue cultures. Cytophysiological effects of lanthanides appear to result from the similarity of their cationic radii to the size of Ca2+ ions. Trivalent lanthanide ions, especially La3+ and Gd3+, block different calcium channels in human and animal cells. Lanthanides can affect numerous enzymes: Dy3+ and La3+ block Ca2+-ATPase and Mg2+-ATPase, while Eu3+ and Tb3+ inhibit calcineurin. In neurons, lanthanide ions regulate the transport and release of synaptic transmitters and block some membrane receptors, e.g. GABA and glutamate receptors. It is likely that lanthanides significantly and uniquely affect biochemical pathways, thus altering physiological processes in the tissues of humans and animals.
Źródło:
Acta Biochimica Polonica; 2000, 47, 4; 1107-1114
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Skin metabolism established with the use of MetaSite for selected retinoids employed in topical and systemic treatment of various skin disorders and found in cosmeceuticals
Autorzy:
Słoczyńska, Karolina
Gunia-Krzyżak, Agnieszka
Żelaszczyk, Dorota
Waszkielewicz, Anna
Marona, Henryk
Powiązania:
https://bibliotekanauki.pl/articles/1039091.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
cytochrome P450
MetaSite
retinoids
skin metabolism
Opis:
Purpose. Besides being widely used in cosmetics, retinoids are potent therapeutic agents used topically and systemically as anti-acne agents. The aim of this study was to predict with the use of MetaSite the skin metabolism of selected retinoids employed in treatment of skin disorders and found in cosmeceuticals. The following compounds were studied: retinol, retinaldehyde, retinoic acid, retinyl acetate, retinyl palmitate, acitretin, etretinate, adapalene and bexarotene. Methods. MetaSite, Molecular Discovery Ltd. is a computational model that enables prediction of cytochrome P450-dependant metabolism. This software indicates atoms in the molecule structure that are mostly vulnerable to metabolic changes and predicts the metabolite structures. Results. MetaSite indicated that retinol and retinal metabolites were obtained through hydroxylation of the methyl group located in the position 3 of the aliphatic chain, whereas retinoic acid biotransformation would occur principally in the carbon atom situated in the position 4 in the cyclohexene ring. In acitretin molecule, carbon atom of the methoxy group attached to the benzene ring displayed the highest probability of biotransformation. In etretinate, metabolic reactions would occur principally on the carbon atom of the final ethyl group of the molecule. Conclusions. MetaSite metabolism predictions for retinoic acid, acitretin, etretinate, adapalene and bexarotene were in agreement with experimental findings. In case of compounds being converted by catalysts other than cytochrome P450 enzymes, the primary metabolites predicted by MetaSite differ from those reported previously. In conclusion, MetaSite is a useful tool that can aid identification of the major metabolites of compounds being administered topically.
Źródło:
Acta Biochimica Polonica; 2015, 62, 2; 201-206
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Potencjalna toksyczność klozapiny wynikająca z interakcji
Potential interaction-related toxicity of clozapine
Autorzy:
Siwek, Marcin
Powiązania:
https://bibliotekanauki.pl/articles/944060.pdf
Data publikacji:
2015
Wydawca:
Medical Communications
Tematy:
clozapine
cytochrome P450
interactions
cytochrom p450
interakcje
klozapina
Opis:
Clozapine is an agent which undergoes intensive cytochrome P450-mediated hepatic metabolism (mainly by 1A2 and, to a lesser extent, by 3A4 and 2D6). The combined use of clozapine with drugs that inhibit these isoenzymes, such as ciprofloxacin, erythromycin, fluoxetine, fluvoxamine, elevates clozapine serum levels, thus increasing the risk or severity of adverse effects and complications typical of clozapine therapy. At the same time, enzymatic inductors (e.g. rifampicin, phenytoin, carbamazepine, St. John’s wort, nicotine, cannabinols) might contribute to reduced efficacy or, after their rapid discontinuation, toxicity of clozapine. The occurrence of synergistic adverse effects due to pharmacodynamic properties is another aspect of the interactions of clozapine with other agents. Sedative, hypotonic, anticholinergic, myelotoxic, and convulsive effects might increase after a simultaneous use of clozapine and other agents inducing the same adverse effects. Clozapine should be used with particular caution during infectious diseases as some of antibiotics (e.g. macrolides) as well as other antimicrobials (e.g. fluorochinolones) and antifungals (mainly azoles) may, by inhibiting clozapine metabolism, increase its myelotoxicity. On the other hand, synergistic myelotoxic effects of clozapine and some of antibiotics (clindamycin, metronidazole) or antipyretic and anti-inflammatory agents (e.g. ibuprofen, paracetamol, metamizole) may occur. Due to the high risk of interactions, clozapine is intended mainly for monotherapy. However, knowledge of the pharmacokinetic and pharmacodynamic properties of clozapine, and thus its potential interactions, allows to include this agent, if necessary, in combined therapy, provided that the necessary precautions are taken.
Klozapina to lek podlegający intensywnemu metabolizmowi wątrobowemu z udziałem izoenzymów cytochromu P450 (głównie 1A2, w mniejszym stopniu 3A4 i 2D6). Łączne stosowanie leków hamujących wymienione izoenzymy, czyli np. ciprofloksacyny, erytromycyny, fluoksetyny lub fluwoksaminy, skutkuje zwiększeniem stężenia klozapiny we krwi pacjenta, co pociąga za sobą wzrost ryzyka pojawienia się bądź nasilenia działań niepożądanych albo powikłań typowych dla leczenia klozapiną. Jednocześnie induktory enzymatyczne (np. rifampicyna, fenytoina, karbamazepina, wyciąg z dziurawca, nikotyna, kanabinole) mogą przyczynić się do spadku skuteczności klozapiny, a po nagłym odstawieniu – do ujawnienia się jej toksyczności. Kolejnym aspektem interakcji klozapiny z innymi lekami jest sumowanie się działań niepożądanych wynikających z właściwości farmakodynamicznych. Działanie sedatywne, hipotonizujące, antycholinergiczne, mielotoksyczne czy drgawkorodne klozapiny może zatem się nasilić, kiedy będzie ona łączona z innymi substancjami również powodującymi takie działania niepożądane. Szczególnej uwagi wymaga stosowanie klozapiny w trakcie chorób infekcyjnych. Z jednej strony bowiem niektóre podawane wówczas antybiotyki (np. makrolidy) oraz inne leki przeciwbakteryjne (np. fluorochinolony) i przeciwgrzybicze (głównie azole) mogą – przez hamowanie metabolizmu klozapiny – przyczyniać się do nasilania jej mielotoksyczności. Z drugiej strony może dochodzić do sumowania się działania mielotoksycznego klozapiny i pewnych antybiotyków (klindamycyna, metronidazol) czy leków przeciwgorączkowych i przeciwzapalnych (np. ibuprofen, paracetamol, metamizol). Ze względu na wysokie ryzyko interakcji klozapina to lek przeznaczony głównie do monoterapii. Jednak znajomość właściwości farmakokinetycznych i farmakodynamicznych klozapiny i wynikających z nich interakcji pozwala, kiedy jest to konieczne, na włączenie jej w schemat terapii kombinowanej – pod warunkiem zachowania należytej ostrożności.
Źródło:
Psychiatria i Psychologia Kliniczna; 2015, 15, 2; 86-91
1644-6313
2451-0645
Pojawia się w:
Psychiatria i Psychologia Kliniczna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
THE EFFECT OF MULTIPLE-DOSE PAROXETINE ON THE PHARMACOKINETIC PROFILE OF CARVEDILOL IN RATS
Autorzy:
Abrudan, Maria B.
Muntean, Dana Maria
Neag, Maria A.
Vlase, Laurian
Gheldiu, Ana Maria
Powiązania:
https://bibliotekanauki.pl/articles/895543.pdf
Data publikacji:
2018-10-31
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
cytochrome P-450
pharmacokinetics
paroxetine
Carvedilol
preclinical study
Opis:
The aim of the present study was to evaluate the effect of multiple-dose paroxetine upon the pharmacokinetic profile of carvedilol in rats. Carvedilol was orally administrated in rats (3.57 mg/kg body mass (b.m.)) in the absence of paroxetine or after a pre-treatment with multiple oral doses of paroxetine (7.14 mg/kg b.m.). The plasma concentrations of carvedilol were estimated by high performance liquid chromatography-tandem mass spectrometry. After carvediol co-administration with paroxetine, an approximately 4.5-fold increase in the exposure of carvedilol was observed, considering the significantly elevated value of AUC0-∞. Furthermore, an increase by 72% of peak plasma concentration was found, as well as an augmentation by 91% of the half life time of carvedilol was observed. Paroxetine co-administration led to a significant alteration of carvedilol’s pharmacokinetic profile in rats, these effects could be explained by the existence of a drug-drug interaction mediated by CYP2D6 inhibition.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2018, 75, 5; 1241-1246
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of single application of paracetamol and/or N-acetylcysteine on rats subchronic exposed to trichloroethylene vapours. I. Effect on hepatic moonooxygenase system dependent of cytochrome P450
Wpływ pojedynczej dawki paracetamolu i/lub N-acetylocysteiny na szczury przewlekle eksponowane na trichloroetylen. I. Wpływ na wątrobowy układ monooksygenaz zależnych od cytochromu P450
Autorzy:
Plewka, Andrzej
Plewka, Danuta
Przystanowicz, Jędrzej
Kowalówka-Zawieja, Joanna
Zielińska-Psuja, Barbara
Powiązania:
https://bibliotekanauki.pl/articles/1178949.pdf
Data publikacji:
2012
Wydawca:
Instytut Medycyny Wsi
Tematy:
N-acetylcysteine
cytochrome P450
liver
paracetamol
trichloroethylene
Opis:
Background: There is a number of factors which potentially affect occurrence of toxic change in liver after overdosing of paracetamol. Hepatic metabolism of trichloroethylene has primary impact on hepatotoxic effect of this solvent. This means that the combined exposure to these xenobiotics can be particularly harmful for human. The influence of N-acetylcysteine (NAC) as a protective factor after paracetamol intoxication was studies. Materials and method: Tests were carried out on rats which were treated with trichloroethylene, paracetamol and/or N-acetylcysteine. In the hepatic microsomal fraction activity of the components of cytochrome P450- dependent monooxygenases was determined Results: Paracetamol slightly stimulated cytochrome P450 having no effect on reductase activity cooperating with it. Cytochrome b5 and its reductase were inhibited by this compound. Trichloroethylene was the inhibitor of compounds of II microsomal electron transport chain. N-acetylcysteine inhibited activity of reductase of NADH-cytochrome b5. Conclusions: Tested doses of the xenobiotics influenced on II microsomal electron transport chain. Protective influence of N-acetylcysteine was better if this compound was applied 2 hours after exposure on xenobiotics.
Wstęp: Istnieje szereg czynników, które potencjalnie wpływają na ryzyko wystąpienia zmian toksycznych w wątrobie po przedawkowaniu paracetamolu. Wątrobowy metabolizm trichloroetylenu ma pierwszorzędny wpływ na hepatotoksyczny efekt tego rozpuszczalnika. Oznacza to, że narażenie łączne na te ksenobiotyki może być szczególnie szkodliwe dla człowieka. Oceniono wpływ N-acetylocysteiny (NAC) jako czynnika osłaniającego po zatruciu paracetamolem. Materiał i metody: Badania wykonano na szczurach, które traktowano trichloroetylenem, paracetamolem i/lub N-acetylocysteiną. We frakcji mikrosomalnej wątroby oznaczano aktywność składników monooksygenaz zależnych od cytochromu P450. Wyniki: Paracetamol lekko stymulował cytochrom P450 nie mając wpływu na aktywność reduktazy współpracującej z nim. Cytochrom b5 i jego reduktaza były hamowane przez ten związek. Trichloroetylen był inhibitorem składników II mikrosomalnego łańcucha transportu elektronów. N-acetylocysteina hamowała aktywność reduktazy NADH-cytochrom b5. Wnioski: Badane dawki ocenianych ksenobiotyków swój wpływ ujawniały raczej na składniki II mikrosomalnego łańcucha transportu elektronów. Ochronny wpływ N-acetylocysteiny był wyraźniejszy, jeśli podano ten związek 2 godziny po zakończeniu ekspozycji na badane ksenobiotyki.
Źródło:
Medycyna Środowiskowa - Environmental Medicine; 2012, 15, 2; 64-71
1505-7054
2084-6312
Pojawia się w:
Medycyna Środowiskowa - Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of acetaminophen and trichloroethylene on liver cytochrome P450-dependent monooxygenase system.
Autorzy:
Plewka, Andrzej
Zielińska-Psuja, Barbara
Kowalówka-Zawieja, Joanna
Nowaczyk-Dura, Grażyna
Plewka, Danuta
Wiaderkiewicz, Anna
Kamiński, Marcin
Orłowski, Jerzy
Powiązania:
https://bibliotekanauki.pl/articles/1044264.pdf
Data publikacji:
2000
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
trichloroethylene
liver
rat
acetaminophen
cytochrome P450,glutathione
Opis:
The aim of the study was to evaluate the effect of acetaminophen (APAP) and/or trichloroethylene (TRI) on the liver cytochrome P450-dependent monooxygenase system, CYP2E1 and CYP1A2 (two important P450 isoforms), and liver glutathione (GSH) content in rats. Rats were given three different doses of APAP (250, 500 and 1000 mg/kg b...) and then the above-mentioned parameters were measured for 48 h. The lowest APAP dose produced small changes in the cytochrome P450 content of liver. At 500 mg/kg APAP increased the cytochrome P450 content to 230% of the control. The inductive effect was seen at 1000 mg/kg dose but at 24 h and later. NADPH-cytochrome P450 reductase activity was the highest after the lowest dose of APAP, while after the highest dose it was equal to the control value. TRI increased both the cytochrome P450 content and the NADPH-cytochrome P450 reductase activity. When TRI was combined with APAP, both these parameters increased in the first hours of observation, but they returned to the control values at 24 h. When APAP was given at 250 mg/kg, GSH levels decreased to 55% of the control at 8 h and returned to the control values at 24 h. The higher doses of APAP decreased GSH levels more than the lowest dose, but after 24 h GSH levels did not differ from those of the control. When TRI was given at 250 mg/kg, the GSH levels decreased to 68% of the control at 2 h and then they increased gradually and tended to exceed the control values at 48 h. The effect of TRI combined with APAP on the level of GSH was virtually the same as that of APAP alone given at 500 mg/kg.
Źródło:
Acta Biochimica Polonica; 2000, 47, 4; 1129-1136
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Arterial ketone index in assessing liver function and its detoxicative capability after ischemia-reperfusion injury.
Autorzy:
Caban, Artur
Wiaderkiewicz, Ryszard
Kamiński, Marcin
Oczkowicz, Grzegorz
Ziaja, Jacek
Powiązania:
https://bibliotekanauki.pl/articles/1044266.pdf
Data publikacji:
2000
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
ischemia
arterial ketone index
cytochrome P450
reperfusion
Opis:
Arterial ketone index (AKBR) which is the ratio of acetoacetic acid to 3-hydroxybutyric acid in the arterial blood, is believed to reflect the mitochondrial reduction potential of hepatocytes and general energy state of the liver. In the presented paper we challenged this hypothesis by analysing the correlation between AKBR and the results of typical liver blood tests (AspAT, AlAT, LDH, CRP) and biotransforming potential of the liver (cytochromes P450, b5 and their corresponding NADPH and NADH reductases) in the model of ischemia-reperfusion injury of rat liver. The results were compared with histochemical analysis of distribution and activity of SDH, LDH and G-6-Pase, the key marker enzymes of the liver. We have shown that, except in the case of acute phase protein (CRP), a decrease in AKBR correlated well with the increase of the level of indicator enzymes in serum. Histochemical analysis also confirmed that AKBR correlates with the degree of damage to hepatocytes during early stage of reperfusion after 60 min of liver ischemia. In the Spearman test, AKBR was significantly correlated with the changes in cytochrome P450 content and its NADPH reductase activity which indicates a high sensitivity of this test. We conclude that the decrease of AKBR value reflects the impairment of basic energy pathways and detoxicative capability of the liver.
Źródło:
Acta Biochimica Polonica; 2000, 47, 4; 1137-1146
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Monooksygenazy zależne od cytochromu P-450 oraz enzymy II fazy przemian ksenobiotykow w łożysku
P-450 cytochrome-dependent monooxygenases and phase II
Autorzy:
Włoch, Stanisław
Powiązania:
https://bibliotekanauki.pl/articles/1039767.pdf
Data publikacji:
2009
Wydawca:
Śląski Uniwersytet Medyczny w Katowicach
Tematy:
cytochrom p-450
biotransformacja
ksenobiotyki
łożysko
cytochrome p-450
biotransformation
xenobiotic
placenta
Opis:
The first part of this paper contains the discussion of the organization of the basic P-450 cytochrome-dependent monooxygenases including the functional differences resulting from their location in the microsomal and mitochondrial fractions, the basic stages of the pertinent metabolic changes, and also, the mechanisms of induction of the Cyp.-450 in the families 1,2,3 and 4. In the next part, the current state of knowledge on monooxygenases in the placental cells has been presented. Attention has been drawn to the fact that despite the low contents of both mRNA and CYP-450 protein in the families 1,2,3 and 4 in syncytiotrophoblast cells at the level of just several percent hepatocytes, this system may perform an important role in the release of indirect toxic metabolites , thus posing threat to the lives of either the embryo or the fetus, particularly in the first trimester of pregnancy. These risks substantially increase in situations where the pregnant woman has had contact with medicines, alcohol, narcotics or tobacco smoke, which are found to be effective CYP-450 inducers or inhibitors. In the final part, the activity of Phase II xenobiotic metabolism enzymes in the placenta has been discussed, including UDP-gluconylotransferase, 5-glutation transferase, and sulfotransferases.
W części pierwszej omówiono organizację podstawowych ogniw monooksygenaz zależnych od cytochromu P-450, różnice funkcjonalne wynikające z ich posadowienia we frakcji mikrosomalnej i mitochondrialnej komórek, podstawowe etapy realizowanych przemian, a także mechanizmy indukcji rodziny 1,2,3 i 4 CYP.-450. Następnie przedstawiono aktualny stan wiedzy na temat monooksygenaz w komórkach łożyska. Zwrócono uwagę, iż pomimo niskich zawartości mRNA i białka CYP-450 rodziny 1,2 oraz 3 w komórkach syncytiotrofoblastu na poziomie zaledwie kilkuprocentowym hepatocytów, układ ten może spełniać ważną rolę w uwalnianiu toksycznych metabolitów pośrednich, stwarzając zagrożenie dla zdrowia i rozwoju zarodka oraz płodu, zwłaszcza w I trymestrze ciąży. Owe zagrożenia zdecydowanie wzrastają w warunkach kontaktu ciężarnej kobiety z lekami, dymem papierosowym, alkoholem, narkotykami, które są efektywnymi induktorami lub inhibitorami CYP-450. Omówiono także aktywność w łożysku enzymów II fazy przemian ksenobiotyków, w tym: UDP-glukonylotransferazy, transferazy S-glutationowej i sufotransferaz.
Źródło:
Annales Academiae Medicae Silesiensis; 2009, 63, 2; 78-84
1734-025X
Pojawia się w:
Annales Academiae Medicae Silesiensis
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of single application of paracetamol and/or N-acetylcysteine on rats in subchronic exposition to trichloroethylene vapours. III. Effect on some isoforms of cytochrome P450 in liver
Wpływ pojedynczej dawki paracetamolu i/lub N-acetylocysteiny na szczury przewlekle eksponowane na trichloroetylen. III. Wpływ na wybrane izoformy cytochromu P450 w wątrobie
Autorzy:
Plewka, Andrzej
Plewka, Danuta
Kowalówka-Zawieja, Joanna
Przystanowicz, Jędrzej
Zielińska-Psuja, Barbara
Powiązania:
https://bibliotekanauki.pl/articles/1178723.pdf
Data publikacji:
2012
Wydawca:
Instytut Medycyny Wsi
Tematy:
N-acetylcysteine
isoforms of cytochrome P450
liver
paracetamol
trichloroethylene
Opis:
Background: In case of overdose of paracetamol the ability of hepatic biotransformation is saturated and accumulation of toxic metabolite – NAPQI takes place. Main CYP isoforms considered to be responsible for bioactivation of APAP and promoting the same liver intoxication are CYP2E1, CYP1A2, CYP3A4 and in animals 2B1/2 isoforms additionally. Purpose of this work was examination of paracetamol influence and/or trichloroethylene on the composition of hepatic cytochrome P450 isoforms. Materials and method: Tests were carried out on rats which were treated with trichloroethylene, paracetamol and/or N-acetylcysteine. In the microsomal fraction content of three isoforms of cytochrome P450 i.e. CYP2E1, CYP2B1/2 and CYP1A2 were determined. Results: Paracetamol slightly stimulated CYP2B1/2 lowering simultaneously level of CYP1A2. Trichloroethylene stimulated CYP2B1/2. N-acetylcysteine stimulated all tested P450 isoforms. N-acetylcysteine given together with examinated xenobiotics induced studied P450 isoforms. Conclusions: N-acetylcysteine demonstrated a protective effect on studied CYP isoforms especially when was given upon termination of xenobiotics exposure.
Wstęp: W przypadku przedawkowania paracetamolu, zdolność wątroby do detoksykacji zostaje wysycona i następuje akumulacja toksycznego metabolitu, jaki jest NAPQI. Główne izoformy CYP, uważane za odpowiedzialne za bioaktywację APAP-u i sprzyjające w ten sposób zatruciom wątrobowym, to CYP2E1, CYP1A2 oraz CYP3A4 a u zwierząt dodatkowo izoformy 2B1/2. Celem pracy było zbadanie wpływu paracetamolu i/lub trichloroetylenu na skład wątrobowych izoform cytochromu P450. Materiał i metody: Badania wykonano na szczurach, które traktowano trichloroetylenem, paracetamolem i/lub N-acetylocysteiną. We frakcji mikrosomalnej wątroby oznaczano zawartość trzech izoform cytochromu P450, tj., CYP2E1, CYP2B1/2 oraz CYP1A2. Wyniki: Paracetamol lekko stymulował CYP2E1 obniżając równocześnie poziom CYP1A2. Trichloroetylen stymulował CYP2B1/2. N-acetylocysteina miała stymulujący wpływ na wszystkie badane izoformy P450. N-acetylocysteina podawana łącznie z badanymi ksenobiotykami prowadziła do wyraźnych wzrostów CYP. Wnioski: N-acetylocysteina wykazywała ochronny wpływ na poziomy badanych izoform cytochromu P450, szczególnie, jeśli została podana zaraz po zaprzestaniu ekspozycji na ksenobiotyki.
Źródło:
Medycyna Środowiskowa - Environmental Medicine; 2012, 15, 4; 24-30
1505-7054
2084-6312
Pojawia się w:
Medycyna Środowiskowa - Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bioactivation of chemicals by cytochromes P450
Autorzy:
Ioannides, C.
Powiązania:
https://bibliotekanauki.pl/articles/363274.pdf
Data publikacji:
2007
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
cytochrom P450
ksenobiotyk
kancerogeneza
aktywacja metaboliczna
cytochrome P450
xenobiotics
carcinogenesis
metabolic activation
Opis:
Most chemical carcinogens require metabolism to generate highly reactive intermediates that manifest their carcinogenicity following covalent interaction with DNA. This bioactivation process is catalysed chiefly by cytochromes P450, a superfamily of enzymes localised primarily in the liver. The carcinogenic activity of a chemical is largely dependent on the profile and concentration of cytochromes P450 at the time of exposure.
Źródło:
Environmental Biotechnology; 2007, 3, 1; 1-9
1734-4964
Pojawia się w:
Environmental Biotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Metabolic activation of adriamycin by NADPH-cytochrome P450 reductase; overview of its biological and biochemical effects.
Autorzy:
Bartoszek, Agnieszka
Powiązania:
https://bibliotekanauki.pl/articles/1043757.pdf
Data publikacji:
2002
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
covalent binding to macromolecules
adriamycin
oxygen radicals
NADPH-cytochrome P450 reductase
Opis:
NADPH-cytochrome P450 reductase (P450 reductase) is one of the enzymes implicated in the metabolism of adriamycin, a very important clinically used antitumour drug. However, apart from the enzyme involvement, so far little was known about the chemical route and biochemical effects of this process. We demonstrated that the application of P450 reductase simultaneously with adriamycin to tumour cells in culture significantly increased cytotoxicity of the drug. Under tissue culture conditions, we noticed also that, in the presence of P450 reductase, adriamycin metabolite(s), displaying an altered spectrum within the visible light range were formed. This observation was taken adavantage of to study the metabolism of adriamycin in cell-free systems, using initially the enzyme isolated from rat liver and the recently obtained recombinant human P450 reductase. The reductive conversion of the drug turned out to be a multi-stage process, which occurred only under aerobic conditions and was accompanied by excessive NADPH consumption. Further research carried out with the aid of radical scavengers and radiolabelled adriamycin revealed that the enhancement of biological activity of adriamycin by P450 reductase stemmed from the formation of alkylating metabolite(s) rather than from the promotion of redox cycling known to be induced in the presence of anthracyclines.
Źródło:
Acta Biochimica Polonica; 2002, 49, 2; 323-331
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Use of cell therapy as a means of targeting chemotherapy to inoperable pancreatic cancer
Autorzy:
Günzburg, Walter
Salmons, Brian
Powiązania:
https://bibliotekanauki.pl/articles/1041363.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
cytochrome P450
chemotherapy
genetically modified cells
cell therapy
encapsulated cells
pancreatic cancer
Opis:
Although approved for the treatment of pancreatic cancer, the chemotherapeutic agent ifosfamide is not an effective therapy for this type of tumour. Ifosfamide must be activated by cytochrome P450 (P450) enzymes in the liver, initially to a short lived intermediate and then to toxic metabolites that are subsequently distributed by the circulatory system. Particularly for pancreatic cancer, this liver-mediated conversion results in relatively high systemic toxicities and poor therapeutic concentrations at the liver-distant site of the tumour. Activation of ifosfamide at the site of the tumour may allow lower doses to be used, while increasing the therapeutic index due to the resultant active concentrations generated locally. A cell-based therapy has been conceived where encapsulated, 293-derived cells genetically modified to overexpress a cytochrome P450 enzyme, are implanted near solid tumours. The cells are encapsulated in polymers of cellulose sulphate in order to provide a means of immunoprotection in vivo as well as to physically constrain them to the vicinity of the tumour. A major advantage of this strategy is that it allows one standard cell line to be applied to all patients and this approach can be extended to the treatment of other tumour types. After proof of principle studies in animal models, a phase I/II clinical trial was initiated in patients with stage III/IV nonresectable pancreatic cancer. Encapsulated cells were angiographically placed into the tumour vasculature of 14 patients and followed by systemic low dose ifosfamide treatment. Angiographic delivery of encapsulated cells proved feasible in all but one patient, and was well tolerated with no capsule or ifosfamide treatment-related adverse events. Four of the treated patients showed tumour regressions after capsule delivery and ifosfamide treatment in computer-tomography scans. The other 10 patients showed no further tumour growth (i.e. stable disease) during 20 weeks observation period. The median life expectancy of the patient collective was extended two fold as compared to age and status matched historical controls, with a 3-fold improvement in one year survival being attained. Evidence for a clinical benefit of the treatment was also obtained on the basis of standard parameters for quality of life. This approach has been evaluated by the European Medicines Evaluation Agency (EMEA) and orphan drug status has been granted. A pivotal clinical trial is now being planned with the help of the EMEA. Taken together, the data from this clinical trial suggest that encapsulated cytochrome P450-expressing cells combined with chemotherapy may be useful for the local treatment of a number of solid tumours and support the performance of further clinical studies of this new treatment.
Źródło:
Acta Biochimica Polonica; 2005, 52, 3; 601-607
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Polimorfizmy genetyczne a efekty metaboliczne działania olanzapiny
Genetic polymorphisms and the metabolic effects of olanzapine
Autorzy:
Sadakierska-Chudy, Anna
Bartosiewicz, Angelika
Powiązania:
https://bibliotekanauki.pl/articles/7454770.pdf
Data publikacji:
2023
Wydawca:
Krakowska Akademia im. Andrzeja Frycza Modrzewskiego
Tematy:
cytochrom P450
efekty uboczne
farmakogenetyka
olanzapina
polimorfizmy SNP
cytochrome P450
adverse side effects
pharmacogenetics
olanzapine
SNP polymorphisms
Opis:
Olanzapina to atypowy lek przeciwpsychotyczny (neuroleptyk) stosowany przede wszystkim w leczeniu schizofrenii. Lek metabolizowany jest głównie przez wątrobowe enzymy cytochromu P450, CYP1A2 i CYP2D6. W metabolizm zaangażowane są również enzymy glukuronidowe, UGT1A i UGT2B10. Olanzapina u niektórych pacjentów wywołuje metaboliczne efekty uboczne, takie jak przyrost masy ciała, a także wzrost poziomu: glukozy, lipidów oraz prolaktyny. Badania farmakogenetyczne wskazują, że polimorfizmy w genach kodujących enzymy metabolizujące lek, transportery oraz inne białka zaangażowane w procesy metaboliczne mogą pomóc wyjaśnić zróżnicowaną odpowiedź pacjentów na leczenie olanzapiną. Zatem profilowanie genetyczne mogłoby być przydatne w praktyce klinicznej, głównie w celu wytypowania pacjentów z podwyższonym ryzykiem wystąpienia działań niepożądanych. Możliwość spersonalizowania terapii ułatwiłaby osiągnięcie pożądanego efektu terapeutycznego i zminimalizowała efekty uboczne.
Olanzapine is an atypical antipsychotic (neuroleptic) used primarily to treat schizophrenia. The drug is mainly metabolized by the hepatic cytochrome P450 enzymes, CYP1A2 and CYP2D6. The glucuronide enzymes UGT1A and UGT2B10 are also involved in its metabolism. In some patients, olanzapine causes metabolic side effects, such as weight gain, an increase in glucose and lipid levels, and an increase in prolactin levels. Pharmacogenetic studies indicate that polymorphisms in genes encoding drug-metabolizing enzymes, transporters, and other proteins involved in metabolic pathways, may help explain the interindividual differences in response to olanzapine treatment. Thus, genetic profiling could be useful in clinical practice, mainly to identify patients with an increased risk of adverse events. The ability to personalize therapy would facilitate maximizing therapeutic efficacy and minimizing side effects.
Źródło:
Państwo i Społeczeństwo; 2023, XXIII, 1; 151-160
1643-8299
2451-0858
Pojawia się w:
Państwo i Społeczeństwo
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
In Vitro approach for identification of a leading cytochrome P450 isoenzyme responsible for biotransformation of novel arylpiperazine drug candidates and their inhibition potency towards CYP3A4.
Autorzy:
Ulenberg, Szymon
Belka, Mariusz
Georgiev, Paweł
Król, Marek
Herold, Franciszek
Bączek, Tomasz
Powiązania:
https://bibliotekanauki.pl/articles/895671.pdf
Data publikacji:
2020-02-29
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
cytochrome P-450
drug-drug interactions
isoform
arylpiperazine
CYP 3A4 inhibitor
metabolic stability
Opis:
Presented article is a follow-up study of previous work, published in PLoS ONE in 2015 regarding metabolic stability of arylpiperazine derivatives, a very promising group of novel antidepressants. The aim of this study was to identify cytochrome P450 (CYP) isoforms that participate in the metabolism of some novel arylpiperazine derivatives developed by authors as well as their potency to inhibit reactions catalysed by identified lead metabolizing enzyme. Such studies allow to predict possible drug-drug interactions that might occur during co-administration of studied compounds with other drugs that are metabolized by identified enzyme. The compounds were incubated in vitro together with the isolated CYP isoforms. After the incubation, samples were analyzed by liquid chromatography coupled with mass spectrometry. The results showed main contribution of CYP3A4 isoform in biotransformation of the investigated derivatives. With CYP3A4 being the main CYP isoform responsible for the metabolism of arylpiperazine derivatives and at the same time being the main metabolizing enzyme for almost 50% of all drugs, a high chance of in vivo drug-drug interactions emerged. Therefore, IC50 values were also determined using testosterone hydroxylation as a probe reaction, specific for CYP3A4. The resulting values ranged from 6.13 to 15.85 µM, which places studied derivatives as moderate or weak inhibitors of CYP3A4. Those results, combined with conclusion that all of the arylpiperazine derivatives are also metabolized to some extent by other CYP isoforms (providing alternative metabolic pathways), result in conclusion that studied arylpiperazines might be safe for co-administration with other CYP3A4 substrates.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2020, 77, 1; 69-76
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of genistein on the gene expressions of androgen generating key enzymes StAR, P450scc and CYP19 in rat ovary
Autorzy:
Chi, X.X.
Chu, X.L.
Zhang, T.
Cao, L.K.
Powiązania:
https://bibliotekanauki.pl/articles/2087521.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
genistein
steroidogenic acute regulatory protein
side-chain cleavage enzymes
cytochrome P450 aromatase
rat ovary
Źródło:
Polish Journal of Veterinary Sciences; 2019, 2; 279-286
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł

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