RGD- and MLD-disintegrins, jarastatin and EC3, activate integrin-mediated signaling modulating the human neutrophils chemotaxis, apoptosis and IL-8 gene expression.
The effects of jarastatin (JT), a monomeric RGD-disintegrin, were compared with those of the heterodimeric MLD-disintegrin, EC3, on human neutrophil activation and functions. Both disintegrins inhibited neutrophil chemotaxis induced by fMet-Leu-Phe and were also potent chemotactic agents. These effects were accompanied by an increase in actin polymerization, and both were inhibited by genistein, a tyrosine kinase inhibitor. While JT, but not other RGD-disintegrins, inhibited EC3-induced chemotaxis, EC3 was not able to inhibit JT effect. The chemotactic effect of JT was blocked by anti-alpha(M) antibody whereas anti-alpha(9)beta(1) inhibited EC3 effect. Both JT and EC3 induced focal adhesion kinase (FAK) and phosphoinositide 3-kinase (PI3K) activation. Accordingly, LY294002, a PI3K inhibitor, impaired their chemotactic effect on neutrophils. JT induced Erk-2 translocation to nucleus and a delay of the spontaneous apoptosis of neutrophils in vitro. In contrast, EC3 inhibited Erk-2 activation and had a proapoptotic effect. These effects were reverted by PD98059, an MEK 1/2 inhibitor and blocked by z-VAD-FMK, a caspase inhibitor. In addition, JT, but not EC3, increased the IL-8 mRNA levels in neutrophils. The data indicate that JT and EC3 directly activate an integrin-coupled signaling and modulate the MAPK pathway in different ways, leading the neutrophils to express different functional response.
Coelho
Ana Lucia J
AL
Departamento de Farmacologia, Instituto de Biologia Roberto Alcântara Gomes, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
De Freitas
Marta S
MS
Mariano-Oliveira
Andrea
A
Rapozo
Davy Carlos M
DC
Pinto
Luis Felipe R
LF
Niewiarowski
Stefan
S
Zingali
Russolina B
RB
Marcinkiewicz
Cezary
C
Barja-Fidalgo
Christina
C
D021581:Active Transport, Cell Nucleus / Q000187:drug effects / Q000502:physiology; D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D002457:Cell Extracts; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D002478:Cells, Cultured; D002634:Chemotaxis, Leukocyte / Q000187:drug effects* / Q000502:physiology; D019483:Disintegrins / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D004347:Drug Interactions / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology; D006801:Humans; D016023:Integrins / Q000187:drug effects* / Q000378:metabolism; D016209:Interleukin-8 / Q000235:genetics; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology; D019950:Mitogen-Activated Protein Kinase 1 / Q000187:drug effects / Q000378:metabolism; D009504:Neutrophils / Q000187:drug effects* / Q000378:metabolism; D010446:Peptide Fragments / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000187:drug effects / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000187:drug effects / Q000378:metabolism; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D014757:Viper Venoms / Q000494:pharmacology*
D000906:Antibodies; D002457:Cell Extracts; D019483:Disintegrins; C119089:EC3 protein, Echis carinatus; D004791:Enzyme Inhibitors; D016023:Integrins; D016209:Interleukin-8; D010446:Peptide Fragments; D012333:RNA, Messenger; D014757:Viper Venoms; C121483:jarastatin; D019869:Phosphatidylinositol 3-Kinases; D011505:Protein-Tyrosine Kinases; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; C496050:PTK2 protein, human; D019950:Mitogen-Activated Protein Kinase 1