The protein kinase C inhibitor AEB071 (sotrastaurin) modulates migration and superoxide anion production by human neutrophils in vitro.
We examined the effect of the protein kinase C-selective inhibitor AEB071 (sotrastaurin) on neutrophil functions in vitro. Pre-incubation with AEB071 at concentrations similar to those reached during in vivo therapy significantly reduced cell capacity to migrate toward three different chemo-attractants and to produce superoxide anions (O₂⁻) in response to phorbol myristate acetate (PMA) or to N-formyl-methionyl-leucyl-phenylalanine (fMLP). AEB071 also significantly inhibited the O₂⁻ overproduction induced by fMLP in neutrophils primed with tumor necrosis factor alpha (TNF-α) or granulocyte/macrophage-colony stimulating factor (GM-CSF). This inhibition was not linked to fMLP-receptor down-regulation since the drug had no effect on either fMLP-receptors or fMLP-induced CD11b membrane expression. When the activity of AEB071 was compared to that of the conventional protein kinase C (PKC) inhibitor Gö6850 (which, like sotrastaurin, inhibits classical and novel PKC isoforms), Gö6976 (an inhibitor of α and α PKC isoforms) and rottlerin (a prevailing δ PKC isoform inhibitor), AEB071 at an equimolar concentration of 3 μM (close to the maximum drug concentration reached in patients treated with AEB071) caused significantly more inhibition on both chemotactic response and superoxide production. These in vitro findings suggest that neutrophils may offer a cellular target for AEB071 activity in vivo.
Rheumatology Unit, Orthopedic Institute Galeazzi IRCCS, University of Milan, Italy. franco.capsoni@unimi.it
F
F
Capsoni
A M
AM
Ongari
E
E
Reali
F
F
Bosè
G F
GF
Altomare
D039481:CD11b Antigen / Q000378:metabolism; D002478:Cells, Cultured; D002634:Chemotaxis, Leukocyte / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism; D006801:Humans; D053583:Interleukin-1beta / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects* / Q000201:enzymology; D018384:Oxidative Stress / Q000187:drug effects*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors* / Q000378:metabolism; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D011758:Pyrroles / Q000494:pharmacology*; D011799:Quinazolines / Q000494:pharmacology*; D044042:Receptors, Formyl Peptide / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D039481:CD11b Antigen; C508606:CXCL8 protein, human; C509295:ITGAM protein, human; D053583:Interleukin-1beta; D016209:Interleukin-8; D047428:Protein Kinase Inhibitors; D011758:Pyrroles; D011799:Quinazolines; D044042:Receptors, Formyl Peptide; D014409:Tumor Necrosis Factor-alpha; D013481:Superoxides; D009240:N-Formylmethionine Leucyl-Phenylalanine; C543528:sotrastaurin; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate