reactive oxygen species production
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- Klíčová slova
- adherence,
- MeSH
- hypoxie MeSH
- integriny fyziologie MeSH
- lidé MeSH
- luminiscenční měření využití MeSH
- makrofágy * fyziologie MeSH
- NADPH-oxidasy sekrece MeSH
- reaktivní formy kyslíku MeSH
- sloučeniny kyslíku metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Cíl: Sledování incidence bakteriospermie, rodového a druhového zastoupení mikroorganizmů a produkce reaktivních kyslíkových částic (ROS) v ejakulátu mužů z neplodných párů v porovnání s fertilními dobrovolníky. Soubor pacientů a metody. Muži z párů léčených pro neplodnost byli rozděleni podle WHO parametrů spermiogramu na normospermiky (skupina A, n = 65) a muže s abnormálním spermiogramem (skupina B, n = 116). Kontrolní skupinu tvořilo 44 dobrovolníků s prokázanou fertilitou (skupina C). Aerobní kultivací bylo prokázáno rodové a druhové zastoupení přítomných mikroorganizmů. Produkce ROS byla vyšetřována chemiluminiscenční metodou. Statistické hodnocení bylo provedeno pomocí Mann -Whitneyova testu. Výsledky. Incidence bakteriospermie mezi skupinami A, B a C (69 %, 74 % a 66 % ) nebyla statisticky významná, převládaly kmeny StaphyJococcus species a Streptococcus species. Signifikantní rozdíl však jsme pozorovali mezi výskytem kmenů Escheríchia coli mezi muži z neplodných párů (skupina A = 11,1 %, B = 9,3 %) a muži fertilními (skupina C = 3,2 %). Neprokázali jsme statisticky signifikantní rozdíly mezi produkcí ROS v kultivačně pozitivních a kultivačně negativních ejakulátech v žádné ze sledovaných skupin. Závěr. Ve všech sledovaných skupinách byla incidence bakteriospermie stejně jako produkce ROS v ejakulátu obdobná. V druhovém zastoupení převažovaly kmeny Staphylococcus species a Streptococcus species ve všech skupinách. Ve vzorcích z neplodných párů bya prokázána signifikantně vyšší přítomnost kmenů Escheríchia coh oproti kontrolní skupině. V produkci ROS nebyly prokázány rozdíly mezi kultivačně pozitivními a negativními vzorky v jednodivých skupinách.
Objective: To estimate the incidence of bacteriospermia, the representation of specific micro-organisms and the generation of reactive oxygen species (ROS) in the semen of males from infertile couples in comparison with the semen of fertile volunteers. Material and Methods: Males from infertile couples were divided according to WHO criteria of their spermiogram results into those with normospermia (Group A, n = 65) and those with semen abnormalities (Group B, n = 116). The control group consisted of 44 fertile volunteers (Group C, n = 44). Aerobic culture was performed to ascertain the genus and species of the present microorganisms. ROS production was estimated by the chemiluminescence method. Statistical analysis was performed using the Mann-Whitney test. Results: The incidence of positive cultures in the semen between Groups A, B and C (69 %, 74 % and 66 %, respectively) did not differ significantly, with Staphylococcus and Streptococcus species being most frequently identified. A significant difference was found only between the occurence of microorganism Escherichia coU in the groups A, B and C (11.1 %, 9.3 % and 3.2 %). There were no statistically significant differences between ROS production in semen with positive or negative culture in any of the studied groups. Conclusions: In all the studied groups, the incidence of bacteriospermia as well as ROS production in the semen were similar. Staphylococcus and Streptococcus species were found in all groups. A significantly higher frequency of Escherichia coh in the semen samples of males from infertile couples in comparison with those from fertile volunteers was observed. No differences in ROS production in semen samples with positive and negative culture results were found in any of the studied groups.
- MeSH
- aerobní bakterie izolace a purifikace klasifikace MeSH
- analýza spermatu klasifikace MeSH
- C-reaktivní protein analýza MeSH
- financování organizované MeSH
- incidence MeSH
- lidé MeSH
- mužská infertilita diagnóza etiologie mikrobiologie MeSH
- reaktivní formy kyslíku analýza MeSH
- sperma chemie mikrobiologie MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
V patogenezi nefropatie krys způsobené aminonukleosidem puromycinu (PAN) se významná role připisuje zvýšené tvorbě reaktivních metabolitů kyslíku (RMK) v glomerulu. Doklady pro tuto hypotézu jsou založeny na poznatku, že látky, které tlumí tvorbu nebo odstraňují RMK, zmírňují proteinurii při PAN. Přímé měření tvorby RMK v izolovaných glomerulech by mohlo tuto hypotézu potvrdit. Inhibitor fosfodiesterázy IV - rolipram - tlumí tvorbu RMK v izolovaných glomerulech. Lze soudit, že by mohl zmírnit klinické projevy PAN. Chemiluminiscenční metodou jsme měřili tvorbu RMK na vrcholu proteinurie v suspenzi izolovaných glomerulů. V jiném pokusu jsme krysám 1 hodinu před a 1 hodinu po podání aminonukleosidu puromycinu aplikovali 25 mg/100 g tělesné váhy rolipramu. Kontrolním krysám byl aplikován pouze aminonukleosid puromycinu. Tvorba RMK izolovanými glomeruly krys s PAN byla statisticky významně nižší (p<0,01) než u kontrol. Inhibitor fosfodieterázy IV - rolipram neměl vliv na výši proteinurie krys s PAN. Závěry: Studie nepotvrdila domněnku o zvýšené tvorbě RMK v glomerulech krys s PAN. Nález jejich snížené tvorby na vrcholu proteinurie však nevylučuje jejich zvýšenou tvorbu v časově omezeném období PAN. Inhibitorem fosfodiesterázy IV, rolipramem, aplikovaným v časném období, se nepodařilo zmírnit klinické projevy PAN, ačkoliv lze soudit, že potlačil tvorbu.
A major role in attributed, in the pathogenesis of puromycin aminonucleoside nephropathy (PAN), to increased rates of production of reactives oxygen metabolites (ROM) in the glomerulus. Evidence for this hypothesis is based on the finding that substances either inhibiting ROM formation or ROM seavengers decrease proteinuria in PAN. Direct measurement of the rate of ROM production in isolated glomeruli could confirm this hypothesis. Rolipram, a phosphodiesterase IV inhibitor, inhibits ROM formation in isolated glomeruli. The implication is it could attenuate the clinical manifestations of PAN. Using chemiluminiscence, we measured ROM formation at peak proteinuria in a suspension of isolated glomeruli. In another experiment, rats were administered rolipram at a dose of 25 mg/100 g b.w. 1 hour before and 1 hour after the administration of puromycin aminonucleoside. Control rats were administered puromycin aminonucleoside only. The rate of ROM formation by isolated glomeruli of rats with PAN was significantly lower (P<0.01) compared with the controls. The phosphodiesterase inhibitor rolipram had no effect on the magnitude of proteinuria in rats with PAN. Conclusions: The study did not confirm the hypothesis of an increased rate of ROM formation in the glomeruli of rats with PAN. However, the finding of their reduced rate of formation at peak proteinuria does not rule out an increased rate of production within the limited period of PAN. The phosphodiesterase inhibitor rolipram administered at an early period, was unable to attenuate the clinical manifestations of PAN while presumably inhibiting ROM formation.
- MeSH
- glomerulus patologie sekrece účinky léků MeSH
- inhibitory fosfodiesteras MeSH
- krysa rodu rattus MeSH
- luminiscence MeSH
- modely nemocí na zvířatech MeSH
- puromycin aminonukleosid škodlivé účinky MeSH
- reaktivní formy kyslíku metabolismus MeSH
- rolipram farmakologie terapeutické užití MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
- Publikační typ
- přehledy MeSH
- srovnávací studie MeSH
Photosystem II (PSII) is a multisubunit protein complex in cyanobacteria, algae and plants that use light energy for oxidation of water and reduction of plastoquinone. The conversion of excitation energy absorbed by chlorophylls into the energy of separated charges and subsequent water-plastoquinone oxidoreductase activity are inadvertently coupled with the formation of reactive oxygen species (ROS). Singlet oxygen is generated by the excitation energy transfer from triplet chlorophyll formed by the intersystem crossing from singlet chlorophyll and the charge recombination of separated charges in the PSII antenna complex and reaction center of PSII, respectively. Apart to the energy transfer, the electron transport associated with the reduction of plastoquinone and the oxidation of water is linked to the formation of superoxide anion radical, hydrogen peroxide and hydroxyl radical. To protect PSII pigments, proteins and lipids against the oxidative damage, PSII evolved a highly efficient antioxidant defense system comprising either a non-enzymatic (prenyllipids such as carotenoids and prenylquinols) or an enzymatic (superoxide dismutase and catalase) scavengers. It is pointed out here that both the formation and the scavenging of ROS are controlled by the energy level and the redox potential of the excitation energy transfer and the electron transport carries, respectively. The review is focused on the mechanistic aspects of ROS production and scavenging by PSII. This article is part of a Special Issue entitled: Photosystem II.
- MeSH
- fotosystém II (proteinový komplex) chemie metabolismus MeSH
- molekulární modely MeSH
- oxidace-redukce MeSH
- přenos energie MeSH
- reaktivní formy kyslíku metabolismus MeSH
- scavengery volných radikálů metabolismus MeSH
- transport elektronů MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Za posledních 25 let se objevilo mnoho důkazů, že reakce volných radikálů hrafi významnou úlohu při vzniku a průběhu řady onemocnění, ale i ve fyziologických dějích organismu. Volné radikály jsou chemické látky obsahující jeden nebo více nepárových elektronů, což je příčinou jejich vysoké reaktivity s řadou biologicky významných látek jako jsou mastné kyseliny, DNA, RNA, aminokyseliny. Volné radikály mohou působit na organismus řadou mechanismů, z nichž nejznámější je peroxidace lipidů, při které vznikají významné toxické produkty jako jsou 4-hydroxy-2,3-trans nonenal (4-HNE) a malondialdehyd. Radikály se uplatňují i při fyziologických reakcích v organismu, jako je tvorba superoxidu v aktivovaném neutrofilním leukocytu, hrají roli v signální transdukci, vznikají při syntéze prostaglandinů a v dalších reakcích. Oxidativní stres tkání a buněk je vyvolán zvýšenou tvorbou volných radikálů a/nebo sníženou kapacitou antioxidačních systémů. Volné radikály jsou zapojeny v procesu stárnutí, v kancerogenezi, zánětlivých a degenerativních onemocněních, aterogenezi a hrají úlohu při ischemicko-reperfuzním a toxickém poškození organismu.
In the past 25 years there emerged many evidence for fi-ee radicals reactions playing an important role not only in the origin and course of a number of diseases, but also in physiologic events in the organism. Free radicals are chemical substances containing one or more un-paired electrons, which cause their high reactivity with many biologically important substances, i.e. fatty acids, DNA, RNA, amino acids. Free radicals can influence the organism in various mechanisms; the well-known is the lipid peroxidation giving rise to important toxic products such as 4-hydroxy 2 3-trans nonenal (4-HNE) a malonedialdehyd. Radicals also take part in the physiologic reactions in the organism, e.g. the production ofsuperoxid in the activated neutrophil leukocyte: they play a role in signal transduction, they are produced during the synthesis of prostaglandins and other reactions. Oxidative Stress (the reaction caused by free radicals) of tissues and cells is caused by excessive free radicals production and/or diminished capacity of antioxidant systems. Free radicals are involved in the aging process, in cancerogenesis, inflammatory and degenerative diseases, atherogenesis, and they play a role in ischemic-reperfusion and toxic injuries of the organism.
The objectives of this study was to investigate the production of reactive oxygen species (ROS) after photodynamic therapy (PDT) in vitro. We examined second generation sensitizers, porphyrines (TPPS4, ZnTPPS4 and PdTPPS4) and compared their effectivity on ROS generation in G361 cell line. Used porphyrines are very efficient water-soluble aromatic dyes with potential to use in photomedicine and have a high propensity to accumulate in the membranes of intracellular organelles like lysosomes and mitochondria. Interaction between the triplet excited state of the sensitizer and molecular oxygen leads to produce singlet oxygen and other ROS to induce cell death. Production of ROS was verificated by molecular probe CM-H2DCFDA and viability of cells was determined by MTT assay. Our results demonstrated that ZnTPPS4 induces the highest ROS production in cell line compared to TPPS4 and PdTPPS4 at each used concentration and light dose. These results consist with a fact that photodynamic effect depends on sensitizer type, its concentration and light dose.
The catalytic role of iron in the Haber-Weiss chemistry, which results in propagation of damaging reactive oxygen species (ROS), is well established. In this review, we attempt to summarize the recent evidence showing the reverse: That reactive oxygen and nitrogen species can significantly affect iron metabolism. Their interaction with iron-regulatory proteins (IRPs) seems to be one of the essential mechanisms of influencing iron homeostasis. Iron depletion is known to provoke normal iron uptake via IRPs, superoxide and hydrogen peroxide are supposed to cause unnecessary iron uptake by similar mechanism. Furthermore, ROS are able to release iron from iron-containing molecules. On the contrary, nitric oxide (NO) appears to be involved in cellular defense against the iron-mediated ROS generation probably mainly by inducing iron removal from cells. In addition, NO may attenuate the effect of superoxide by mutual reaction, although the reaction product-peroxynitrite-is capable to produce highly reactive hydroxyl radicals.
Metal ions play a crucial role in enzymatic reactions in all photosynthetic organisms such as cyanobacteria, algae and plants. It well known that metal ions maintain the binding of substrate in the active site of the metalloenzymes and control the redox activity of the metalloenzyme in the enzymatic reaction. A large pigment-protein complex, PSII, known to serve as a water-plastoquinone oxidoreductase, contains three metal centers comprising non-heme iron, heme iron of Cyt b559 and the water-splitting manganese complex. Metal ions bound to PSII proteins maintain the electron transport from water to plastoquinone and regulate the pro-oxidant and antioxidant activity in PSII. In this review, attention is focused on the role of PSII metal centers in (i) the formation of superoxide anion and hydroxyl radicals by sequential one-electron reduction of molecular oxygen and the formation of hydrogen peroxide by incomplete two-electron oxidation of water; and (ii) the elimination of superoxide anion radical by one-electron oxidation and reduction (superoxide dismutase activity) and of hydrogen peroxide by two-electron oxidation and reduction (catalase activity). The balance between the formation and elimination of reactive oxygen species by PSII metal centers is discussed as an important aspect in the prevention of photo-oxidative damage of PSII proteins and lipids.
- MeSH
- cytochromy typu b chemie metabolismus MeSH
- fotosystém II (proteinový komplex) chemie metabolismus MeSH
- katalytická doména MeSH
- kovy metabolismus MeSH
- kyslík metabolismus MeSH
- mangan metabolismus MeSH
- molekulární modely MeSH
- oxidace-redukce MeSH
- reaktivní formy kyslíku metabolismus MeSH
- rostliny enzymologie MeSH
- scavengery volných radikálů metabolismus MeSH
- sinice enzymologie MeSH
- voda metabolismus MeSH
- železo metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
OBJECTIVES: The generation of reactive oxygen species (ROS) by phagocytes is one of the irreplaceable microbicidal tools of innate immunity. It has been reported in our previous studies that short-term treatment by carvedilol ex vivo inhibits ROS generation. The purpose of this study was to investigate the long-term effect of carvedilol on phagocytes. METHODS: Human leukemia HL-60 cells differentiated into granulocyte-like cells were used as the model. Final concentrations of carvedilol were 0.1-100 micromol/l. The production of ROS by HL-60 cells was measured using luminol-enhanced chemiluminescence (CL). RESULTS: Carvedilol in concentrations 0.1-10 micromol/l did not exhibit any toxic effect on cells (measured using bioluminescent bacteria Photorhabdus luminescens subsp. thracensis). One hour's treatment with 10 micromol/l carvedilol significantly decreased both spontaneous and activated CL of cells. Conversely, no inhibitory effects on CL were observed in 10 micromol/l carvedilol after 48 h incubation; lower concentrations of carvedilol even slightly increased the CL activity of HL-60 cells. A significant increase in spontaneous CL activity was detected in cells incubated with 10 micromol/l carvedilol in comparison with the control. Powerful antioxidative properties of carvedilol against peroxyl radical (ORAC assay) were proved. No scavenging of nitric oxide (electrochemical method) was observed. CONCLUSIONS: Long-term influence of carvedilol can induce an increase in the generation of phagocyte-derived ROS and potentially also other inflammatory mediators. The increased ROS production is compensated for by antioxidative properties of carvedilol although the increased production of inflammatory mediators could affect the proper function of immune system.
- MeSH
- adenosintrifosfát metabolismus MeSH
- beta blokátory farmakologie toxicita MeSH
- buněčná diferenciace účinky léků MeSH
- fagocyty účinky léků MeSH
- fluorometrie MeSH
- granulocyty účinky léků MeSH
- HL-60 buňky MeSH
- karbazoly farmakologie toxicita MeSH
- lidé MeSH
- luminiscence MeSH
- oxid dusnatý metabolismus MeSH
- peroxidy metabolismus MeSH
- proliferace buněk účinky léků MeSH
- propanolaminy farmakologie toxicita MeSH
- reaktivní formy kyslíku metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Wound healing is a complex physiological process important for tissue homeostasis. An acute injury initiates massive cell migration, proliferation and differentiation, synthesis of extracellular matrix components, scar formation and remodelling. Blood flow and tissue oxygenation are parts of the complex regulation of healing. Higher organisms utilize molecular oxygen as a terminal oxidant. This way of gaining energy for vital processes such as healing leads to the production of a number of oxygen compounds that may have a defensive or informatory role. They may be harmful when present in high concentrations. Both the lack and the excess of reactive oxygen species may influence healing negatively.
- MeSH
- financování organizované MeSH
- granulační tkáň cytologie chemie MeSH
- hojení ran fyziologie MeSH
- hyperbarická oxygenace využití MeSH
- hypoxie patofyziologie MeSH
- lidé MeSH
- peroxidy farmakologie terapeutické užití MeSH
- reaktivní formy kyslíku farmakologie metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH