Effect of carvedilol on reactive oxygen species and enzymes linking innate and adaptive immunity.
OBJECTIVE
Neutrophils and macrophages are critical components of our innate host defenses. They are a potential source of nitric oxide (NO) and superoxide, known to play an important role in many physiological processes including defense, immune and inflammatory responses. Myeloperoxidase (MPO), a major NO scavenger and a marker of oxidative stress, as well as increased inducible nitric oxide synthase (iNOS) expression, may affect the NO-superoxide balance, critical for cellular redox balance in the cardiovascular system at physiologic conditions. The effect of carvedilol was studied on stimulated superoxide generation, MPO release and iNOS expression in phagocytes by using receptor operating stimuli [N-formyl-Met-Leu-Phe (FMLP), lipopolysaccharide (LPS) and specific inhibitors (wortmannin, propranolol).


METHODS
Superoxide generation was measured as superoxide dismutase inhibitable reduction of cytochrome c (550 nm), MPO activity as the oxidation of o-dianisidine in the presence of hydrogen peroxide in a spectrophotometer Hewlet Packard 8452 A (463 nm). Expression of iNOS (Western-blot analysis) in RAW 264.7 cell line (murine macrophages) was stimulated by lipopolysaccharide (LPS).


RESULTS
Carvedilol dose-dependently decreased superoxide generation and MPO release from intact neutrophils stimulated by FMLP. In the highest concentration tested, carvedilol pronounced the effect of wortmannin [inhibitor of phospholipase D (PLD) regulatory pathway] and significantly decreased LPS stimulated iNOS expression in RAW 264.7 cell line.


CONCLUSIONS
The conceivable cumulative non-specific membrane effect of carvedilol and its effect on PLD signalling pathway contribute to the decrease of both superoxide generation and MPO release, thus supporting the restoration of NO-superoxide balance.
Pecivová
Jana
J
Institute of Experimental Pharmacology, Slovak Academy of Sciences, Bratislava, Slovakia. jana.pecivova@savba.sk
Macicková
Tatiana
T
Lojek
Antonín
A
Gallová
Lucie
L
Cíz
Milan
M
Nosál'
Rado
R
Holománová
Dagmar
D
D000818:Animals; D002227:Carbazoles / Q000494:pharmacology*; D000077261:Carvedilol; D002478:Cells, Cultured; D007111:Immunity, Cellular / Q000187:drug effects*; D007113:Immunity, Innate / Q000187:drug effects*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D009195:Peroxidase / Q000378:metabolism; D011412:Propanolamines / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013481:Superoxides / Q000378:metabolism
D002227:Carbazoles; D011412:Propanolamines; D017382:Reactive Oxygen Species; D000077261:Carvedilol; D013481:Superoxides; D009240:N-Formylmethionine Leucyl-Phenylalanine; D009195:Peroxidase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse