enzymatic activity
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Metodami luminol-dependentní chemiluminiscence byla sledována antioxidační aktivita N-(alkoxyfenyl)-2-(2-oxo-l-aza-l-cykloalkyl) acetamidů zkoumaných pro své potenciálně pozitivní působení na kognitivní funkce, stobadinu a jeho acylderivátů, které tvoří tzv. prodrug formu této látky se zvýšenou lipofilitou. V pokusech in vitro byl sledován vliv na produkci reaktivních kyslíkových metabolitů aktivovanými leukocyty. Dále byla stanovena celková antioxidační aktivita odpovídající schopnosti vychytávat peroxylový radikál a antioxidační aktivita vůči superoxidovému radikálu (generovaném v enzymatickém systému hypoxantin/xantinoxidasa) a hydroxylovému radikálu (generovanému Fentonovou reakcí). Antioxidační aktivita testovaných látek byla ve všech případech porovnána se stobadin dihydrochloridem. Antioxidační aktivita byla ve všech systémech ověřena u stobadinu a stanovena u jeho butyrylderivátu. Cinnamoylstobadin účinně snižoval pouze chemiluminiscenční aktivitu leukocytů. Potenciální zesilovače kognitivních funkcí byly antioxidačně neúčinné.
The luminol-enhanced chemiluminiscence method was used to investigate the antioxidative activity of N-(alkoxyphenyl)-2-(2-oxo-l-aza-l-cykloalkyl) acetamides studied as potential cognitive enhancers and stobadine acylderivatives which form prodrugs with increased lipophilicity. The effect on the production of reactive oxygen metabolites by activated leukocytes was studied in vitro. Furthermore, the total radical-trapping antioxidant parameter was evaluated as the peroxyl radical-trapping capacity and the scavenging effect on the superoxide anion radical (generated by the enzymatic system hypoxanthine/xanthine oxidase) and on the hydroxyl radical (produced in Fenton reaction) were studied. The antioxidative properties of the tested substances were compared with that of stobadine dihydrochloride. Only stobadine and its butyrylderivative have been demonstrated to possess free radical scavenging activity in all systems. Cinnamoylstobadine inhibited only the leukocyte chemiluminiscence activity. The potential cognitive enhancers did not show any antioxidant activity.
- Klíčová slova
- STOBADIN,
- MeSH
- acetamidy MeSH
- alkylace MeSH
- antioxidancia MeSH
- indoly MeSH
- luminiscence MeSH
- pyridinové sloučeniny MeSH
- MeSH
- hladovění MeSH
- hypoxie MeSH
- krysa rodu rattus MeSH
- mozek patofyziologie růst a vývoj MeSH
- Check Tag
- krysa rodu rattus MeSH
Sixty-four breast-fed infants and 23 calves were investigated for bacteria and enzymatic activity in their faecal samples. The bacteria were measured using cultivation and fluorescence in situ hybridization. Enzymatic activity was also examined. Forty-seven (64%) infants and all the calves had high numbers of bifidobacteria (usually >9 log CFU g-1) in their faeces, but 17 infants (36%) did not have a detectable amount of the bacteria. Most of the bifidobacteria-negative infants had significant quantities of clostridia in their faecal flora. While the infants did not have significantly higher counts of bifidobacteria, the samples from calves contained significantly (P<0.05) more coliform bacteria and lactobacilli. There were also significant differences in their enzymatic activities. Bifidobacteria-positive samples had a greater alpha-glucosidase activity, while bifidobacteria-negative samples had a lower activity of alpha-galactosidase, and calf samples had the highest beta-glucuronidase activity. A significant increase in bifidobacteria in calf faeces between days 3 and 7 was accompanied by a decrease in Escherichia coli. Our results show that the faecal flora of calves is similar to that of infants with regard to the occurrence of bifidobacteria as a dominant bacterial group.
- MeSH
- alfa-galaktosidasa metabolismus MeSH
- alfa-glukosidasy metabolismus MeSH
- beta-galaktosidasa metabolismus MeSH
- Bifidobacterium izolace a purifikace MeSH
- feces enzymologie mikrobiologie MeSH
- financování organizované MeSH
- hybridizace in situ fluorescenční MeSH
- lidé MeSH
- počet mikrobiálních kolonií MeSH
- skot MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- skot MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- srovnávací studie MeSH
Aktivita antioxidačných enzýmov CuZn-SOD, Mn-SOD a CAT bola meraná spektrofotometricky v hipokampe, striate a kortexe po 5 min. ischémie, použitej ako preconditioning a následnej reperfúzie (5 hod., 1 a 2 dni). Signifikantné zvýšenie CuZn-SOD aktivity bolo po všetkých reperfúznych časoch, predovšetkým po 5 hod. reperfúzii (3násobne) vo všetkých nami sledovaných oblastiach mozgu, najvyššie zvýšenia boli zistené v selektívne vulnerabilných oblastiach hippocampu a striata. Podobné zmeny boli zaznamenané v aktivite Mn-SOD. Aktivita CAT bola zvýšená tiež, ale najvyšší nárast bol po 24 hod. reperfúzie. V našom experimente sme aplikovali proteínový inhibítor cykloheximid, aby sme dokázali, že nárast aktivity SOD a CAT bol spôsobený proteosyntézou de-novo v prvých hodinách reperfúzie. Naše výsledky naznačujú, že obidva antioxidačné enzýmy sú syntetizované počas prvých 5 hod. reperfúzie.
The activities of the antioxidant enzymes CuZn-SOD, Mn-SOD and CAT were measured in the hippocampus, striatum and cortex after 5 min. of ischemia used as a preconditioning and subsequent reperfusion, by spectrophotometric methods. In all ischemiareperfusion groups (5 hours, 1 day, 2 days of reperfusion), CuZn-SOD activities were found to be increased if compared to the sham operated controls. The increase was significant (P < 0.05) in all reperfusion groups, particularly after 5 hours of reperfusion (3-times) in all studied brain regions; the largest increase was detected in the more vulnerable hippocampus and striatum. Very similar changes were found in Mn-SOD activity. The activity of CAT was increased too, but reached the peak of postischemic activity 24 hours after ischemia. Our attempt to understand the mechanizms of increased SOD and CAT activities by application of protein synthesis inhibitor cycloheximide showed that this increase was caused by de novo synthesis of enzymes during first hours after ischemia. Our findings indicate that both major endogenous antioxidant enzymes SOD and CAT are synthesized as soon as 5 hours after ischemia. In spite of significant upregulation of these enzymes a large number of neurons in selectively vulnerable CA1 region of hippocampus undergoes to neurodegeneration within 7 days after ischemia.
