title: Inhibitory effects on human eosinophil chemotaxis in vitro by BAY 41-2272, an activator of nitric oxide-independent site of soluble guanylate cyclase.
abstract: This study was designed to investigate the effects of the 5-cyclopropyl-2-[1-(2-fluoro-benzyl)-1H-pyrazolo[3,4-b]pyridin-3-yl]-pyrimidin-4-ylamine (BAY 41-2272) on formyl-methionyl-leucyl-phenylalanine (fMLP; 10(-7)M)-induced human eosinophil chemotaxis, cyclic guanosine-3',5'-monophosphate (cGMP) and cyclic adenosine-3',5'-monophosphate (cAMP) levels. Human eosinophils were pretreated or not with 3-isobutyl-l-methyl-xanthine (IBMX; 500microM), and then exposed to BAY 41-2272 (0.1-10.0microM) for either short (10min) or prolonged (90min) time periods. Exposition of eosinophils with BAY 41-2272 for either 10min or 90min markedly inhibited the eosinophil chemotaxis, independently of IBMX pretreatment. Inhibition of fMLP-induced eosinophil chemotaxis by BAY 41-2272 (in absence of prior treatment with IBMX) was about of the same irrespective if cells were exposed for 10min or 90min with this compound. In IBMX-pretreated eosinophils, the inhibition of fMLP-induced chemotaxis by BAY 41-2272 in the 10-min exposure protocols was even higher in comparison with the 90-min protocols. Incubation of IBMX-treated eosinophils for 90min with BAY 41-2272 resulted in 2.0-2.5 times higher levels of cGMP and cAMP compared with the 10-min protocols. The BAY 41-2272-induced cGMP increases were abolished by pre-incubation of eosinophils with the soluble guanylate cyclase inhibitor 1H-[1,2,4]-oxidiazolo[4,3-a] quinoxalin-1-one (ODQ). No eosinophil toxicity was observed in any experimental condition, according to 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide (MTT) assay. Our findings show that inhibitory effects of fMLP-induced human eosinophil chemotaxis by BAY 41-2272 at short-term or prolonged exposition time are accompanied by significant elevations of cGMP and cAMP, but we could not detect a clear correlation between chemotaxis inhibition and elevation of cyclic nucleotide levels.
authors.affiliation: Department of Pharmacology, Faculty of Medical Sciences, UNICAMP, P.O. Box 6111, 13084-971 Campinas (SP), Brazil. thomazzi@directnet.com.br <thomazzi@directnet.com.br>
authors.forename: Sara M
authors.initials: SM
authors.lastname: Thomazzi
authors.forename: Juliana
authors.initials: J
authors.lastname: Moreira
authors.forename: Gilberto
authors.initials: G
authors.lastname: De Nucci
authors.forename: Edson
authors.initials: E
authors.lastname: Antunes
mesh_terms: D000293:Adolescent; D000328:Adult; D002634:Chemotaxis, Leukocyte / Q000187:drug effects* / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004804:Eosinophils / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005260:Female; D006162:Guanylate Cyclase / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism*; D011720:Pyrazoles / Q000494:pharmacology*; D011725:Pyridines / Q000494:pharmacology*; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism*; D000071756:Soluble Guanylyl Cyclase
chemical_list: C423582:3-(4-Amino-5-cyclopropylpyrimidine-2-yl)-1-(2-fluorobenzyl)-1H-pyrazolo(3,4-b)pyridine; D011720:Pyrazoles; D011725:Pyridines; D018160:Receptors, Cytoplasmic and Nuclear; D009569:Nitric Oxide; D006162:Guanylate Cyclase; D000071756:Soluble Guanylyl Cyclase