Defective Zn
2+ homeostasis in mouse and human platelets with α- and δ-storage pool diseases.
Sci Rep 2019;
9:8333. [PMID:
31171812 PMCID:
PMC6554314 DOI:
10.1038/s41598-019-44751-w]
[Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 05/22/2019] [Indexed: 12/31/2022] Open
Abstract
Zinc (Zn2+) can modulate platelet and coagulation activation pathways, including fibrin formation. Here, we studied the (patho)physiological consequences of abnormal platelet Zn2+ storage and release. To visualize Zn2+ storage in human and mouse platelets, the Zn2+ specific fluorescent dye FluoZin3 was used. In resting platelets, the dye transiently accumulated into distinct cytosolic puncta, which were lost upon platelet activation. Platelets isolated from Unc13d−/− mice, characterized by combined defects of α/δ granular release, showed a markedly impaired Zn2+ release upon activation. Platelets from Nbeal2−/− mice mimicking Gray platelet syndrome (GPS), characterized by primarily loss of the α-granule content, had strongly reduced Zn2+ levels, which was also confirmed in primary megakaryocytes. In human platelets isolated from patients with GPS, Hermansky-Pudlak Syndrome (HPS) and Storage Pool Disease (SPD) altered Zn2+ homeostasis was detected. In turbidity and flow based assays, platelet-dependent fibrin formation was impaired in both Nbeal2−/− and Unc13d−/− mice, and the impairment could be partially restored by extracellular Zn2+. Altogether, we conclude that the release of ionic Zn2+ store from secretory granules upon platelet activation contributes to the procoagulant role of Zn2+ in platelet-dependent fibrin formation.
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