2-Benzyloxybenzaldehyde inhibits formyl-methionyl-leucyl-phenylalanine stimulation of phospholipase D activation in rat neutrophils

• Published in: Biochimica et biophysica acta Vol. 1573; no. 1; pp. 26 - 32
• Main Authors: Wang, Jih-Pyang, Chang, Ling-Chu, Hsu, Mei-Feng, Huang, Li-Jiau, Kuo, Sheng-Chu
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 10.10.2002
• Subjects: ADP-ribosylation factor; ADP-Ribosylation Factors - metabolism; Animals; Benzaldehydes - pharmacology; Calcium - metabolism; Cell Membrane - drug effects; Cell Membrane - metabolism; Dose-Response Relationship, Drug; Enzyme Activation - drug effects; Enzyme Inhibitors - pharmacology; Glycerophospholipids - metabolism; Intracellular free Ca 2; N-Formylmethionine Leucyl-Phenylalanine - antagonists & inhibitors; N-Formylmethionine Leucyl-Phenylalanine - pharmacology; Neutrophil; Neutrophils - drug effects; Neutrophils - metabolism; Phosphatidic Acids - metabolism; Phospholipase D; Phospholipase D - antagonists & inhibitors; Phospholipase D - metabolism; Protein tyrosine phosphorylation; Rats; Rats, Sprague-Dawley; Rho A; rhoA GTP-Binding Protein - metabolism; ADP-ribosylation factor; Neutrophil; Protein tyrosine phosphorylation; Intracellular free Ca 2; Phospholipase D; Rho A
• ISSN: 0304-4165; 0006-3002; 1872-8006
• DOI: 10.1016/S0304-4165(02)00329-X

2-Benzyloxybenzaldehyde (CCY1a) inhibited the formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated phospholipase D (PLD)-mediated products, phosphatidic acid (PA) and phosphatidylethanol (PEt) formation in rat neutrophils in a concentration-dependent manner with IC 50 values of 15.8±2.5 and 13.9±2.0 μM, respectively. The underlying cellular signaling mechanism of CCY1a inhibition was investigated. CCY1a inhibited the plateau phase but not the initial Ca 2+ spike of fMLP-stimulated Ca 2+ signal. CCY1a did not inhibit the [Ca 2+] i change in Ca 2+-free medium in response to fMLP, but inhibited the [Ca 2+] i change by the subsequent addition of Ca 2+. In addition, CCY1a treatment attenuated the fMLP-induced protein tyrosine phosphorylation. The membrane translocation of ADP-ribosylation factor (ARF) and Rho A proteins in neutrophils stimulated with fMLP was attenuated by CCY1a in a concentration-dependent manner. In a cell-free system, neither the membrane association of ARF and Rho A caused by GTPγS nor the phorbol myristate acetate-stimulated membrane translocation of Rho A was suppressed significantly by CCY1a. These results indicate that the attenuation of protein tyrosine phosphorylation, blockade of Ca 2+ entry, and the suppression of ARF and Rho A membrane translocation are probably obligatory for the CCY1a inhibition of PLD activity in rat neutrophils in response to fMLP.