Protease-activated receptor-2 (PAR-2) is a member of seven transmembrane domain G protein-coupled receptors activated by proteolytic cleavage whose better known member is the thrombin receptor. The pathophysiological role of PAR-2 remains poorly understood. Because PAR-2 is involved in inflammatory and injury response events, we investigated the role of PAR-2 in experimental myocardial ischemia-reperfusion injury. We show for the first time that PAR-2 activation protects against reperfusion-injury. After PAR-2-activating peptide (2AP) infusion, we found a significant recovery of myocardial function and decrease in oxidation at reflow. Indeed, the glutathione cycle (glutathione and oxidized glutathione) and lipid peroxidation analysis showed a reduced oxidative reperfusion-injury. Moreover, ischemic risk zone and creatine kinase release were decreased after PAR-2AP treatment. These events were coupled to elevation of PAR-2 and tumor necrosis factor α (TNFα) expression in both nuclear extracts and whole heart homogenates. The recovery of coronary flow was not reverted by L-nitroarginine methylester, indicating a NO-independent pathway for this effect. Genistein, a tyrosine kinase inhibitor, did not revert the PAR-2AP effect. During early reperfusion injuryin vivonot only oxygen radicals are produced but also numerous proinflammatory mediators promoting neutrophil and monocyte targeting. In this context, we show that TNFα and PAR-2 are involved in signaling in pathophysiological conditions, such as myocardial ischemia-reperfusion. At the same time, because TNFα may exert pro-inflammatory actions and PAR-2 may constitute one of the first protective mechanisms that signals a primary inflammatory response, our data support the concept that this network may regulate body responses to tissue injury.

Protease-activated receptor-2 modulates myocardial ischemia-reperfusion injury in the rat heart / Cicala, Carlo; Wallace, John L.; Santagada, Vincenzo; Caliendo, Giuseppe; Ignarro, Louis J.; Cirino, Giuseppe; Napoli, Claudio; De Nigris, Filomena; Franconi, Flavia. - 97:7(2000), pp. 3678-3683.

Protease-activated receptor-2 modulates myocardial ischemia-reperfusion injury in the rat heart

Franconi, Flavia
2000-01-01

Abstract

Protease-activated receptor-2 (PAR-2) is a member of seven transmembrane domain G protein-coupled receptors activated by proteolytic cleavage whose better known member is the thrombin receptor. The pathophysiological role of PAR-2 remains poorly understood. Because PAR-2 is involved in inflammatory and injury response events, we investigated the role of PAR-2 in experimental myocardial ischemia-reperfusion injury. We show for the first time that PAR-2 activation protects against reperfusion-injury. After PAR-2-activating peptide (2AP) infusion, we found a significant recovery of myocardial function and decrease in oxidation at reflow. Indeed, the glutathione cycle (glutathione and oxidized glutathione) and lipid peroxidation analysis showed a reduced oxidative reperfusion-injury. Moreover, ischemic risk zone and creatine kinase release were decreased after PAR-2AP treatment. These events were coupled to elevation of PAR-2 and tumor necrosis factor α (TNFα) expression in both nuclear extracts and whole heart homogenates. The recovery of coronary flow was not reverted by L-nitroarginine methylester, indicating a NO-independent pathway for this effect. Genistein, a tyrosine kinase inhibitor, did not revert the PAR-2AP effect. During early reperfusion injuryin vivonot only oxygen radicals are produced but also numerous proinflammatory mediators promoting neutrophil and monocyte targeting. In this context, we show that TNFα and PAR-2 are involved in signaling in pathophysiological conditions, such as myocardial ischemia-reperfusion. At the same time, because TNFα may exert pro-inflammatory actions and PAR-2 may constitute one of the first protective mechanisms that signals a primary inflammatory response, our data support the concept that this network may regulate body responses to tissue injury.
2000
Protease-activated receptor-2 modulates myocardial ischemia-reperfusion injury in the rat heart / Cicala, Carlo; Wallace, John L.; Santagada, Vincenzo; Caliendo, Giuseppe; Ignarro, Louis J.; Cirino, Giuseppe; Napoli, Claudio; De Nigris, Filomena; Franconi, Flavia. - 97:7(2000), pp. 3678-3683.
File in questo prodotto:
File Dimensione Formato  
Napoli_C_Articolo_2000_Protease.pdf

accesso aperto

Tipologia: Versione editoriale (versione finale pubblicata)
Licenza: Non specificato
Dimensione 156.32 kB
Formato Adobe PDF
156.32 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11388/264520
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact