Decreasing phosphodiesterase 5A activity contributes to platelet cGMP accumulation during storage of apheresis-derived platelet concentrates
Version of Record online: 2 AUG 2013
© 2013 American Association of Blood Banks
Volume 54, Issue 4, pages 1008–1014, April 2014
How to Cite
Kobsar, A., Putz, E., Yilmaz, P., Weinig, E., Boeck, M. and Koessler, J. (2014), Decreasing phosphodiesterase 5A activity contributes to platelet cGMP accumulation during storage of apheresis-derived platelet concentrates. Transfusion, 54: 1008–1014. doi: 10.1111/trf.12360
- Issue online: 11 APR 2014
- Version of Record online: 2 AUG 2013
- Manuscript Revised: 12 JUN 2013
- Manuscript Accepted: 12 JUN 2013
- Manuscript Received: 27 APR 2013
Platelet storage lesion (PSL) considerably decreases the quality of platelets (PLTs) in concentrates characterized by a loss of signaling responses to agonists and impaired PLT activation, secretion, and aggregation. To understand the role of inhibitory signaling pathways in the mechanism of PSL, the basal state of the cyclic nucleotide (CN)-dependent signaling systems in stored PLTs was investigated.
Study Design and Methods
Whole blood samples (WB) and apheresis-derived PLT concentrates (APCs) were obtained from healthy volunteers. Washed PLTs were prepared from WB on Day 0 and from APCs on Days 0, 2, and 5. The basal phosphorylation of the vasodilator-stimulated phosphoprotein (VASP) and phosphodiesterase 5A (PDE5A) levels were quantified by Western blot. CN and PDE5A activity were measured by enzyme-linked immunoassay kits. Fibrinogen binding and aggregation were measured in PLT-rich plasma of WB or APC samples. Unpaired t test was used for statistical analysis.
Basal VASP phosphorylation levels were comparable in WB and APCs on Day 0. VASP phosphorylation increased significantly during storage of APCs, more pronounced at Ser239 than at Ser157. Similarly, intracellular cGMP, but not cAMP, concentration continuously increased in stored PLTs, whereas PDE5A levels and activity significantly decreased accompanied by diminished thrombin receptor activator peptide 6–induced fibrinogen binding and aggregation.
Storage of APCs leads to intracellular cGMP accumulation that could be caused by degradation of PDE5A. Enhanced cGMP level supports subsequent cGMP-dependent protein kinase–mediated increase of VASP phosphorylation resulting in reduced fibrinogen binding and aggregation.