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ABSTRACT: The aim of this study was to evaluate the effects of pinosylvin (PIN) and pterostilbene (PTE), natural substances from the stilbenoid group, on the development of adjuvant arthritis in rats.
Adjuvant arthritis (AA) was induced by a single intradermal injection of Mycobacterium butyricum in incomplete Freund's adjuvant in male Lewis rats. Our experiments included healthy intact animals as reference controls, arthritic animals without any drug administration, and arthritic animals with administration of PIN and PTE in the oral daily dose of 30 mg/kg b.w. The treatment involved administration of the substances tested from day 0, i.e. the day of immunization, to the experimental day 28. The following parameters were monitored: change of the hind paw volume (HPV) on day 14, 21 and 28, luminol-enhanced chemiluminescence (CL) of the joint and myeloperoxidase (MPO) activity in hind paw joint homogenates (day 28).
Arthritic animals treated with PIN showed a decrease in HPV, significantly on days 14 and 28. PIN decreased CL of the joint as well as MPO activity of the joint homogenate, in comparison with untreated animals. PTE had no effect on HPV and MPO activity in hind paw joint homogenates and exerted only a partial effect on luminol-enhanced CL.
On the basis of our results we conclude that the effect of PTE on CL was only partial. PIN, on the other hand, had a beneficial anti-inflammatory and antioxidant effect on oxidative stress induced biochemical changes occurring in AA, as determined by all three functional parameters.
Neuro endocrinology letters 12/2010; 31 Suppl 2:91-5. · 1.30 Impact Factor
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ABSTRACT: We analysed and compared the effect of five H1-antihistamines on stimulated oxidative burst at extra- and intracellular level of isolated and stimulated human polymorphonuclear leukocytes.
Oxidative burst of isolated human neutrophils was studied by means of luminol and isoluminol enhanced chemiluminescence.
The following rank order of potency for H1-antihistamines to decrease chemiluminescence was evaluated extracellularly: dithiaden> loratadine> chlorpheniramine> brompheniramine> pheniramine and at intracellular site: loratadine> dithiaden.
H1-antihistamines differ substantially according to their chemical structure in suppressing oxidative burst both at extra- and intracellular site of isolated stimulated human neutrophils.
Neuro endocrinology letters 12/2009; 30 Suppl 1:133-6. · 1.30 Impact Factor
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ABSTRACT: There is incomplete information about host immune response to maggot therapy, nowadays increasingly used to clean chronic wounds from necrotic debris and infection. Maggots are applied to the wound during the inflammatory phase. At the same time neutrophils infiltrate the inflammatory site as the first defense line of the organism. Myeloperoxidase (MPO) and reactive oxygen species, generated during the respiratory burst by neutrophils, are the key players participating in microbial killing as well as in signalling pathways.
We studied the effect of an extract from salivary glands (SGE) of Lucilia sericata (L. sericata) on opsonized zymosan stimulated whole blood chemiluminescence (CL), superoxide generation and MPO release from human neutrophils.
Formation of reactive oxygen species in whole blood was determined by luminol-enhanced CL. superoxide generation was measured as superoxide dismutase inhibitable reduction of cytochrome c, MPO activity as the oxidation of o-dianisidine in the presence of hydrogen peroxide.
Crude SG extract of L. sericata had no significant effect either on superoxide generation and MPO release from isolated unstimulated human neutrophils or on activity of isolated enzymes. Crude SG extract of L. sericata in the highest concentration used significantly decreased opsonized zymosan (0.5 mg/ml) stimulated blood CL, superoxide generation and MPO release.
On the basis of our results as well as from the literature we suggest that the beneficial effects of maggot therapy might involve the decrease of generation and release of proinflammatory factors, while neither phagocytosis nor subsequent apoptosis is disturbed.
Neuro endocrinology letters 11/2008; 29(5):794-7. · 1.30 Impact Factor
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ABSTRACT: To compare three stimuli which activate human neutrophils with different signal transduction mechanisms, in order to better localize the effect of the beta-adrenoceptor antagonist carvedilol (CARV) on superoxide generation (O2*-) and myeloperoxidase release (MPO). The effect of CARV [0.1-100 micromol/l] on O2*- generation and MPO release from isolated human neutrophils was studied after specific receptor activator N-formyl-methionyl-leucyl-phenylalanine (fMLP) and nonreceptor phorbol-12-myristate-13-acetate (PMA) and calcium ionophor (A23187) stimuli.
O2*- generation was measured as superoxide dismutase inhibitable reduction of cytochrome c and MPO release as the oxidation of o-dianisidine in the presence of hydrogen peroxide in a spectrophotometer Hewlet Packard 8452 A at respective 550 and 463 nm.
CARV had no effect on O2*- generation and MPO release in nonstimulated cells. In the concentration 10 and 100 micromol/l, it significantly decreased fMLP and PMA stimulated O2*- generation and MPO release. Incubation of neutrophils with CARV [100 micromol/l] caused significant inhibition of O2*- generation and MPO release induced by A23187. Wortmannin, a specific inhibitor of 1-phosphatidylinositol-3-kinase, inhibited significantly only fMLP stimulated O2*- generation. CARV [100 micromol/l] with wortmannin [50 nmol/l] further decreased O2*- generation after the same stimulus.
CARV decreased O2*- generation and MPO release from isolated human neutrophils both by membrane-operating stimulus - fMLP and membrane bypassing activators - PMA and A 23187. This fact, together with effect the of wortmannin, indicates that the inhibition may be attributed to the non-specific action of CARV and its interference with phospholipase D signaling pathway, which plays only a minor role in proteinkinase C stimulated O2*- generation.
Neuro endocrinology letters 11/2008; 29(5):790-3. · 1.30 Impact Factor
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ABSTRACT: 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.
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).
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.
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.
Neuro endocrinology letters 11/2008; 29(5):779-83. · 1.30 Impact Factor
