The p38 mitogen-activated protein kinase pathway plays a critical role in thrombin-induced endothelial chemokine production and leukocyte recruitment.
Thrombin, the terminal serine protease in the coagulation cascade, is a proinflammatory molecule in vivo and induces endothelial activation in vitro. The cellular signaling mechanisms involved in this function are unknown. The role of the p38 mitogen-activated protein kinase (MAPK) signaling pathway in thrombin-induced chemokine production was studied. Phosphorylation of both p38 MAPK and its substrate, ATF-2, was observed in human umbilical vein endothelial cells (HUVECs) stimulated with thrombin, with a maximum after 5 minutes of stimulation. Using the selective p38 MAPK inhibitor SB203580, there was a significant decrease in thrombin-induced interleukin-8 (IL-8) and monocyte chemotactic protein-1 (MCP-1) protein production and messenger RNA steady-state levels. In addition, SB203580 decreased IL-8 and MCP-1 production induced by the thrombin receptor-1 agonist peptide (TRAP), suggesting functional links between the thrombin G protein-coupled receptor and the p38 MAPK pathway. Furthermore, endothelial activation in the presence of SB203580 decreased the chemotactic activity of thrombin-stimulated HUVEC supernatant on neutrophils and monocytic cells. In contrast, the p42/p44 MAPK pathway did not appear to be involved in thrombin- or TRAP-induced endothelial chemokine production, because there was no reduction in the presence of the p42/p44-specific inhibitor PD98059. These results demonstrate that the p38 rather than p42/44 MAPK signaling pathway plays an important role in thrombin-induced endothelial proinflammatory activation and suggest that inhibition of p38 MAPK may be an interesting target for anti-inflammatory strategies in vascular diseases combining thrombosis and inflammation. (Blood. 2001;98:667-673)
Marin
V
V
Laboratoire d'Immunologie-INSERM U387, Hôpital Sainte-Marguerite, 270 blvd Sainte-Marguerite, 13009 Marseille, France.
Farnarier
C
C
Grès
S
S
Kaplanski
S
S
Su
M S
MS
Dinarello
C A
CA
Kaplanski
G
G
D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000096:biosynthesis; D018925:Chemokines / Q000096:biosynthesis*; D002634:Chemotaxis, Leukocyte / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D007249:Inflammation / Q000378:metabolism; D016209:Interleukin-8 / Q000096:biosynthesis; D007700:Kinetics; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism / Q000502:physiology*; D010766:Phosphorylation / Q000187:drug effects; D015398:Signal Transduction / Q000187:drug effects*; D013917:Thrombin / Q000494:pharmacology*; D014471:Umbilical Veins / Q000166:cytology; D048051:p38 Mitogen-Activated Protein Kinases
D018932:Chemokine CCL2; D018925:Chemokines; D016209:Interleukin-8; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D013917:Thrombin