It is well documented that the polysaccharide glucomannan (GM), an abundant constituent of the fungal cell wall, in the form of particulate induces strong activation of phagocytes, however, the effects of soluble GM are not known. Activation of phagocyte anti-microbial mechanisms is a crucial part of the innate host defense against invading pathogens. However, under uncontrolled inflammatory conditions they contribute to damage of surrounding tissues. Thus, to prevent these deleterious effects, the activation of phagocytes is a tightly regulated process. Therefore, in this study we analyzed the effect of soluble GM on some neutrophil functions such as reactive oxygen species production, degranulation, and receptor mobilization at the plasma membrane. Soluble GM at the tested concentrations did not stimulate oxidative burst of phagocytes directly but significantly potentiated oxidative burst in response to opsonized zymosan particles. GM induced significant phosphorylation of p47phox subunit of NADPH oxidase on Ser345. This priming effect of GM was accompanied by time and concentration dependent degranulation characterized by increased surface expression of receptors stored in neutrophil granules (CD10, CD11b, CD14, CD35, and CD66b). Degranulation was further confirmed by increase of elastase activity in media. Thus, it could be suggested that soluble GM induces priming of phagocytes connected with their degranulation, the increase of surface receptor expression, and potentiation of oxidative burst response to opsonized particles through the activation of NADPH oxidase.

• MeSH
• Candida chemie   MeSH
• fagocyty účinky léků   metabolismus   MeSH
• fosforylace účinky léků   MeSH
• GTP-vázající protein RAC2 MeSH
• lidé MeSH
• mannany farmakologie   MeSH
• NADPH-oxidasy metabolismus   MeSH
• rac proteiny vázající GTP metabolismus   MeSH
• respirační vzplanutí účinky léků   MeSH
• zymosan farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• (1-6)-alpha-glucomannan MeSH Prohlížeč
• mannany MeSH
• NADPH-oxidasy MeSH
• neutrophil cytosolic factor 1 MeSH Prohlížeč
• rac proteiny vázající GTP MeSH
• zymosan MeSH

Results of ultramicroscopic investigations of phagocytes isolated from non-secreting and aberrantly secreting juvenile mammary glands of non-pregnant heifers are presented. The two types of phagocytes observed in cell suspensions obtained by lavage of mammary gland cavities were polymorphonuclear leukocytes and macrophages. Polymorphonuclear leukocytes were spherical or irregular in shape and contained segmented nuclei. Azurophilic and specific electron-dense granules, mitochondria, glycogen particles, phagosomes and phagolysosomes in cytoplasma and characteristic pseudopodia on the cell surface were observed. In addition to these normal polymorphonuclear leukocytes, degenerating cells, characterized by spherical nuclei, total absence of pseudopodia, merged nuclear segments and altered granules, other cellular organelles and plasmalemma were present. Two types of macrophages, i.e. vacuolized and non-vacuolized, could be distinguished. Typical of the non-vacuolized type was a kidney-shaped nucleus, a rich Golgi complex and a large amount of lysosomes in the cytoplasm. The vacuolized macrophages contained a large amount of electron-dense vacuoles in the cytoplasm. Unlike non-secreting glands, the cell suspensions collected from aberrantly secreting juvenile mammary glands contained only vacuolized macrophages. The vacuolization results from phagocytosis of corpuscular particles of aberrant milk plasma.

• MeSH
• fagocyty ultrastruktura   MeSH
• makrofágy ultrastruktura   MeSH
• mléčné žlázy zvířat cytologie   MeSH
• neutrofily ultrastruktura   MeSH
• skot anatomie a histologie   MeSH
• vakuoly ultrastruktura   MeSH
• zvířata MeSH
• Check Tag
• skot anatomie a histologie   MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Apocynin is a naturally occurring methoxy-substituted catechol, experimentally used as an inhibitor of NADPH oxidase. Since it acts as a potent inhibitor in studies with neutrophils and macrophages, no inhibitory effect can often be found in non-phagocyte cells. In our experiments, apocynin even stimulated reactive oxygen species (ROS) production by vascular fibroblasts. Even when added to macrophages, apocynin initially caused an increase in ROS production. The inhibition of ROS formation followed, suggesting that in the presence of leukocyte myeloperoxidase and hydrogen peroxide, apocynin is converted to another compound. Apocynin pre-activated with H2O2 and horseradish peroxidase (HRP) inhibited ROS production immediately. In non-phagocytes, apocynin stimulated ROS production and no inhibition was observed even after 60 min. Apocynin treated with H2O2 and HRP, however, decreased ROS production in the same manner as in macrophages. The stimulatory effect on ROS production can be abolished by tiron and superoxide dismutase (SOD), suggesting that superoxide was the produced species. The effect of apocynin was inhibited by diphenylene iodinium (DPI), a non-scavenging NADPH oxidase inhibitor. It can be summarized that apocynin stimulates cell superoxide production. In the presence of peroxidase and hydrogen peroxide, however, it is converted into another compound that acts as an inhibitor of superoxide production. It strongly suggests that under conditions in vivo, apocynin can have opposite effects on phagocytes and non-phagocyte cells. It acts as an inhibitor of phagocyte NADPH oxidase but also as a ROS production stimulator in non-phagocyte cells.

• MeSH
• acetofenony farmakologie   MeSH
• antioxidancia farmakologie   MeSH
• aorta účinky léků   metabolismus   MeSH
• fagocyty enzymologie   MeSH
• fibroblasty účinky léků   metabolismus   MeSH
• inhibitory enzymů farmakologie   MeSH
• krysa rodu Rattus MeSH
• kultivované buňky MeSH
• NADPH-oxidasy antagonisté a inhibitory   MeSH
• potkani Wistar MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• acetofenony MeSH
• acetovanillone MeSH Prohlížeč
• antioxidancia MeSH
• inhibitory enzymů MeSH
• NADPH-oxidasy MeSH
• reaktivní formy kyslíku MeSH

Serotonin, the major secretory product of activated platelets, has been widely reported as regulating various constituents of the immune system and immune functions. This modulation is complex and the data available are rather controversial. The aim of the present study was to clarify the mechanisms of serotonin action on human phagocytes. The effect of serotonin in a concentration range of 10(-7) M-10(-3) M on various parameters of oxidative burst of phagocytes was studied using various luminol-enhanced chemiluminescence methods. Serotonin inhibited the chemiluminescence response of the cells in a dose dependent manner. The effect of serotonin on the activity of myeloperoxidase was studied in further experiments. In this case, serotonin again exerted a dose dependent inhibition of the myeloperoxidase activity. The hypothesis that the inhibitory activity of serotonin might be also receptor mediated was evaluated using various serotonin receptor agonists and antagonists. None of the agonists studied exerted any direct antioxidative properties. Only (+/-)-DOI hydrochloride, a selective 5-HTR(2) agonist, exerted similar effects on phagocytic cells as serotonin. It can be concluded that serotonin could affect the oxidative burst of phagocytes. Responsibility for its inhibitory effects lies with both the decrease in the generation of reactive oxygen species (due to the inhibition of myeloperoxidase activity) and with direct scavenging of reactive oxygen species. The effect of serotonin on phagocytes is also partially mediated by 5-HTR(2) receptor.

• MeSH
• fagocyty metabolismus   MeSH
• lidé MeSH
• luminiscenční měření MeSH
• peroxidasa antagonisté a inhibitory   MeSH
• receptory serotoninové 5-HT2 MeSH
• respirační vzplanutí účinky léků   MeSH
• serotonin farmakologie   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• peroxidasa MeSH
• receptory serotoninové 5-HT2 MeSH
• serotonin MeSH

The purpose of the study was to investigate the effects of H(1)-antihistamines of the 1(st) generation (antazoline, bromadryl, brompheniramine, dithiaden, cyclizine, chlorcyclizine, chlorpheniramine, clemastine) and the 2(nd) generation (acrivastine, ketotifen, and loratadine) on the respiratory burst of phagocytes. Reactive oxygen species generation in neutrophils isolated from rat blood was measured using luminol-enhanced chemiluminescence. Changes in nitrite formation and iNOS protein expression by RAW 264.7 macrophages were analysed using Griess reaction and Western blotting. The antioxidative properties of drugs in cell-free systems were detected spectrophotometrically, luminometrically, fluorimetrically, and amperometrically. The majority of the H(1)-antihistamines tested (bromadryl, brompheniramine, chlorcyclizine, chlorpheniramine, clemastine, dithiaden, and ketotifen) exhibited a significant inhibitory effect on the chemiluminescence activity of phagocytes. H(1)-antihistamines did not show significant scavenging properties against superoxide anion and hydroxyl radical, thus this could not contribute to the inhibition of chemiluminescence. H(1)-antihistamines had a different ability to modulate nitric oxide production by LPS-stimulated macrophages. Bromadryl, clemastine, and dithiaden were the most effective since they inhibited iNOS expression, which was followed by a significant reduction in nitrite levels. H(1)-antihistamines had no scavenging activity against nitric oxide. It can be concluded that the effects observed in the H(1)-antihistamines tested are not mediated exclusively via H(1)-receptor pathway or by direct antioxidative properties. Based on our results, antihistamines not interfering with the microbicidal mechanisms of leukocytes (antazoline, acrivastine and cyclizine) could be used preferentially in infections. Other antihistamines should be used, under pathological conditions accompanied by the overproduction of reactive oxygen species.

• Klíčová slova
• antihistamines, nitric oxide, oxidative burst, phagocytes, reactive oxygen species,
• Publikační typ
• časopisecké články MeSH

OBJECTIVES: The effects of non-modified and oxidatively modified calf skin collagen type I on platelet aggregation and the oxidative burst of phagocytes were examined in the framework of a general hypothesis that collagen, platelets and phagocytes cooperate to modulate the oxidative burst of phagocytes and the extent of oxidative stress. MATERIALS AND METHODS: Calf skin collagen type I was subjected to oxidative modification by hydrogen peroxide or hydroxyl radical. Thermal denaturation of collagen was performed in a spectrophotometer equipped with a temperature gradient device. The aggregation of isolated human platelets obtained after differential centrifugation was measured using a dual-channel aggregometer. The production of reactive oxygen species by human whole blood phagocytes was evaluated by luminol-enhanced chemiluminescence. RESULTS: Oxidative modification of collagen samples was characterized by a decrease in denaturation transition temperature. Oxidatively modified samples showed a modified SDS-PAGE pattern, evidencing a significant destruction of the collagen. All oxidatively modified collagen samples, independent of the oxidation treatment applied, lost their platelet-aggregating and phagocyte oxidative burst-inducing activity. CONCLUSION: The results suggest that reactive oxygen species were able to modify collagen. On the other hand, oxidatively modified collagen lost its activating properties towards platelets and phagocytes.

• MeSH
• absorpce MeSH
• agregace trombocytů * MeSH
• centrifugace MeSH
• denaturace proteinů MeSH
• elektroforéza v polyakrylamidovém gelu MeSH
• fagocyty metabolismus   MeSH
• hydroxylový radikál chemie   MeSH
• kolagen typu I chemie   metabolismus   MeSH
• kůže * MeSH
• lidé MeSH
• luminiscence MeSH
• oxidace-redukce MeSH
• peroxid vodíku chemie   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• respirační vzplanutí * MeSH
• skot MeSH
• spektrofotometrie MeSH
• teplota MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• hydroxylový radikál MeSH
• kolagen typu I MeSH
• peroxid vodíku MeSH
• reaktivní formy kyslíku MeSH

Developmental changes of functional ability of peripheral blood phagocytes from days 1 to 100 of life were investigated. Luminol enhanced chemiluminiscence was used to establish the ability of phagocytes to produce reactive oxygen species (ROS). Simple superoxide anion production was determined by spectrophotometrical measurement of cytochrome c. Activity of surface aminopeptidase N was assessed by spectrophotometrical measurement of l-alanine-p-nitroanilide. Flow cytometric measurements of CD18 and CD45 expression were performed. The ROS production per 0.5microl of blood did not show any trend; however, the values recalculated per 500 granulocytes had a decreasing course. The most noteworthy increase in production of superoxide anion occurred between days 17 and 26. Activity of aminopeptidase N decreased during the first 4 weeks. Expression of CD18 and CD45 intensively increased from days 1 to 14 with gradual decrease by day 100. Natural immunity develops during the early postnatal life and seems to be influenced by exposure of the organism to environmental antigens.

• MeSH
• antigeny CD13 krev   imunologie   MeSH
• antigeny CD18 imunologie   MeSH
• antigeny CD45 imunologie   MeSH
• fagocyty imunologie   MeSH
• longitudinální studie MeSH
• luminiscenční měření veterinární   MeSH
• novorozená zvířata MeSH
• počet leukocytů veterinární   MeSH
• prasata krev   imunologie   MeSH
• přirozená imunita imunologie   MeSH
• průtoková cytometrie veterinární   MeSH
• spektrofotometrie ultrafialová veterinární   MeSH
• superoxidy krev   imunologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny CD13 MeSH
• antigeny CD18 MeSH
• antigeny CD45 MeSH
• superoxidy MeSH

The aim of this work was to evaluate ontogeny of reactive nitrogen species (RNS) production by peripheral blood phagocytes in pig. Pig fetuses (55 and 92 days of gestation) and postnatal piglets (1, 3, 8, 17, 31 and 41 days after birth) were used. RNS production was measured by fluorescent probes diaminofluorescein-diacetate (DAF-FMDA) and dichloro-fluorescein-diacetate (H2DCFDA). Levels of nitration of cell proteins were established by immunofluorescent detection of nitrotyrosine. Levels of plasma nitrites/nitrates were detected spectrophotometrically by Griess reaction. Nitric oxide production measured by DAF-FMDA in neutrophils decreased during postnatal life. Spontaneous RNS measured by H2DCFDA decreased from 55th day of gestation to the 41st day of life. Phorbol-12-myristate-13-acetate activated production decreased during postnatal life. Production of NO measured by DAF-FMDA in macrophages decreased from the first to 41st day after birth. RNS production measured by H2DCFDA in monocytes did not show any significant changes during ontogeny. The level of nitrotyrosine significantly decreased from the third to 17th day. Levels of plasma nitrites/nitrates gradually decreased from the 55th day of gestation to the 41st day after birth. A temporary increase in all parameters occurred after weaning, but without any significance. In conclusion, RNS production has a decreasing trend during ontogeny and is transiently upregulated after weaning.

• MeSH
• fagocyty metabolismus   MeSH
• longitudinální studie MeSH
• novorozená zvířata MeSH
• odstavení MeSH
• oxid dusnatý metabolismus   MeSH
• reaktivní formy dusíku metabolismus   MeSH
• stárnutí krev   MeSH
• Sus scrofa krev   embryologie   růst a vývoj   MeSH
• vývoj plodu MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• oxid dusnatý MeSH
• reaktivní formy dusíku MeSH

AIMS: The diverse physiological functions of histamine are mediated through distinct histamine receptors. In this study we investigated the role of H2R and H4R in the effects of histamine on the production of reactive oxygen species by phagocytes in whole blood. MAIN METHODS: Changes in reactive oxygen species (ROS) production by whole blood phagocytes after treatment with histamine, H4R agonists (4-methylhistamine, VUF8430), H2R agonist (dimaprit) and their combinations with H4R antagonist (JNJ10191584) and H2R antagonist (ranitidine) were determined using the chemiluminescence (CL) assay. To exclude the direct scavenging effects of the studied compounds on the CL response, the antioxidant properties of all compounds were measured using several methods (TRAP, ORAC, and luminol-HRP-H2O2 based CL). KEY FINDINGS: Histamine, 4-methylhistamine, VUF8430 and dimaprit inhibited the spontaneous and OZP-activated whole blood CL in a dose-dependent manner. On the other hand, only VUF8430 was able to inhibit PMA-activated whole blood CL. Ranitidine, but not JNJ10191584, completely reduced the effects of histamine, 4-methylhistamine and dimaprit. The direct scavenging ability of tested compounds was negligible. SIGNIFICANCE: Our results demonstrate that the inhibitory effects of histamine on ROS production in whole blood phagocytes were caused by H2R. Our results also suggest that H4R agonists in concentrations higher than 10(-6)M may also influence ROS production via binding to H2R.

• Klíčová slova
• H(2)R, H(4)R, Histamine, Histamine receptors, Phagocytes, Reactive oxygen species,
• MeSH
• agonisté histaminu farmakologie   MeSH
• benzimidazoly farmakologie   MeSH
• dimaprit farmakologie   MeSH
• fagocyty účinky léků   metabolismus   MeSH
• guanidiny farmakologie   MeSH
• histamin fyziologie   MeSH
• histaminový receptor H4 MeSH
• lidé MeSH
• methylhistaminy farmakologie   MeSH
• reaktivní formy kyslíku krev   MeSH
• receptory histaminu H2 metabolismus   MeSH
• receptory histaminu metabolismus   MeSH
• receptory spřažené s G-proteiny agonisté   metabolismus   MeSH
• thiomočovina analogy a deriváty   farmakologie   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 4-methylhistamine MeSH Prohlížeč
• agonisté histaminu MeSH
• benzimidazoly MeSH
• dimaprit MeSH
• guanidiny MeSH
• histamin MeSH
• histaminový receptor H4 MeSH
• HRH4 protein, human MeSH Prohlížeč
• JNJ 10191584 MeSH Prohlížeč
• methylhistaminy MeSH
• reaktivní formy kyslíku MeSH
• receptory histaminu H2 MeSH
• receptory histaminu MeSH
• receptory spřažené s G-proteiny MeSH
• S-(2-guanidylethyl)isothiourea MeSH Prohlížeč
• thiomočovina MeSH

Uptake of bacteria by phagocytes is a crucial step in innate immune defence. Members of the disintegrin and metalloproteinase (ADAM) family critically control the immune response by limited proteolysis of surface expressed mediator molecules. Here, we investigated the significance of ADAM17 and its regulatory adapter molecule iRhom2 for bacterial uptake by phagocytes. Inhibition of metalloproteinase activity led to increased phagocytosis of pHrodo labelled Gram-negative and -positive bacteria (E. coli and S. aureus, respectively) by human and murine monocytic cell lines or primary phagocytes. Bone marrow-derived macrophages showed enhanced uptake of heat-inactivated and living E. coli when they lacked either ADAM17 or iRhom2 but not upon ADAM10-deficiency. In monocytic THP-1 cells, corresponding short hairpin RNA (shRNA)-mediated knockdown confirmed that ADAM17, but not ADAM10, promoted phagocytosis of E. coli. The augmented bacterial uptake occurred in a cell autonomous manner and was accompanied by increased release of the chemokine CXCL8, less TNFα release and only minimal changes in the surface expression of the receptors TNFR1, TLR6 and CD36. Inhibition experiments indicated that the enhanced bacterial phagocytosis after ADAM17 knockdown was partially dependent on TNFα-activity but not on CXCL8. This novel role of ADAM17 in bacterial uptake needs to be considered in the development of ADAM17 inhibitors as therapeutics.

• Klíčová slova
• ADAM17, bacterial phagocytosis, chemokines, iRhom2, infection, inflammation, metalloproteinase, phagocytes, shedding,
• MeSH
• antigeny CD36 genetika   metabolismus   MeSH
• Escherichia coli patogenita   MeSH
• fagocytóza MeSH
• fagocyty metabolismus   mikrobiologie   MeSH
• interleukin-8 metabolismus   MeSH
• intracelulární signální peptidy a proteiny genetika   metabolismus   MeSH
• kultivované buňky MeSH
• lidé MeSH
• myši MeSH
• protein ADAM17 genetika   metabolismus   MeSH
• RAW 264.7 buňky MeSH
• receptory TNF - typ I genetika   metabolismus   MeSH
• Staphylococcus aureus patogenita   MeSH
• THP-1 buňky MeSH
• toll-like receptor 6 genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ADAM17 protein, human MeSH Prohlížeč
• antigeny CD36 MeSH
• CD36 protein, human MeSH Prohlížeč
• interleukin-8 MeSH
• intracelulární signální peptidy a proteiny MeSH
• protein ADAM17 MeSH
• receptory TNF - typ I MeSH
• RHBDF2 protein, human MeSH Prohlížeč
• TLR6 protein, human MeSH Prohlížeč
• toll-like receptor 6 MeSH