Intraplatelet signaling mechanisms of the priming effect of matrix metalloproteinase-2 on platelet aggregation
Authors: G Guglielmini
E Falcinelli
P Gresele
M Torti
Journal: Journal of Thrombosis and Haemostasis (2005)
Discipline: CLINICAL MEDICINE
Keywords: Platelets; MMP-2; signal transduction; platelet activation; calcium influx
Affiliations: Department of Internal Medicine, Division of Internal and Cardiovascular Medicine, University of Perugia, Perugia, Italy.

Abstract:  Objective: Platelets contain and release some matrix metalloproteinases (MMPs), enzymes involved in the degradation of extracellular matrix, and one of these (MMP-2) exerts a proaggregatory effect. We explored the signal transduction mechanisms activated by MMP-2 in human blood platelets. Methods and results: Recombinant, human MMP-2, added before stimulation with subthreshold doses of different agonists, potentiated platelet activation, calcium influx, IP3 formation, and pleckstrin phosphorylation. Wortmannin and LY29400, two PI3-K inhibitors, suppressed the potentiating effects of MMP-2 and preincubation with MMP-2 enhanced the thrombin-induced association of the p85alpha PI3-K subunit with the cytoskeleton and increased the phosphorylation of PKB. Protein tyrosine kinase inhibitors, MAP kinase inhibitors, PLA2 inhibitors, cyclooxygenase inhibitors and antagonists of the P2Y1 and P2Y12 receptors did not affect the potentiating activity of MMP-2 on platelets. Conclusion: Our data show that MMP-2, at a concentration released by activated platelets, facilitates platelet activation acting at the level of a second messenger system common to different agonists and related to the activation of PI3-K. Platelet-released MMP-2 may contribute to platelet activation in vivo. 

Retracted: No

PubPeer comments:
 Brought to my attention by another reader. In Fig 1D, the d1 control image appears to be the same as the d4 pFUS image (day 4). It appears that the differences in the images can be explained if the brightness has been increased in the red channel and if the contrast has been changed in the blue channel in the pFUS image. Some common features highlighted. Could the authors explain these apparent issues? *** ![file] , 
 Published 24 January 2020 This corrigendum corrects a figure error in the original version of this publication. Panel D of Figure 1, showing representative images of mesenchymal stromal cells in kidney tissue, contained an accidental image duplication. The corrected figure panel is supplied below. This correction does not alter or affect the statistical measurements made in the figure or any conclusions of the original article. The authors apologize for the oversight and any inconvenience it may have caused. ![file] , 
 Published 24 January 2020 This corrigendum corrects a figure error in the original version of this publication. Panel D of Figure 1, showing representative images of mesenchymal stromal cells in kidney tissue, contained an accidental image duplication. The corrected figure panel is supplied below. This correction does not alter or affect the statistical measurements made in the figure or any conclusions of the original article. The authors apologize for the oversight and any inconvenience it may have caused. file ,