TY  - JOUR
A1  - Mammadova-Bach, Elmina
A1  - Braun, Attila
T1  - Zinc homeostasis in platelet-related diseases
JF  - International Journal of Molecular Sciences
N2  - Zn\(^{2+}\) deficiency in the human population is frequent in underdeveloped countries. Worldwide, approximatively 2 billion people consume Zn\(^{2+}\)-deficient diets, accounting for 1–4% of deaths each year, mainly in infants with a compromised immune system. Depending on the severity of Zn\(^{2+}\) deficiency, clinical symptoms are associated with impaired wound healing, alopecia, diarrhea, poor growth, dysfunction of the immune and nervous system with congenital abnormalities and bleeding disorders. Poor nutritional Zn\(^{2+}\) status in patients with metastatic squamous cell carcinoma or with advanced non-Hodgkin lymphoma, was accompanied by cutaneous bleeding and platelet dysfunction. Forcing Zn\(^{2+}\) uptake in the gut using different nutritional supplementation of Zn\(^{2+}\) could ameliorate many of these pathological symptoms in humans. Feeding adult rodents with a low Zn\(^{2+}\) diet caused poor platelet aggregation and increased bleeding tendency, thereby attracting great scientific interest in investigating the role of Zn\(^{2+}\) in hemostasis. Storage protein metallothionein maintains or releases Zn\(^{2+}\) in the cytoplasm, and the dynamic change of this cytoplasmic Zn\(^{2+}\) pool is regulated by the redox status of the cell. An increase of labile Zn\(^{2+}\) pool can be toxic for the cells, and therefore cytoplasmic Zn\(^{2+}\) levels are tightly regulated by several Zn\(^{2+}\) transporters located on the cell surface and also on the intracellular membrane of Zn\(^{2+}\) storage organelles, such as secretory vesicles, endoplasmic reticulum or Golgi apparatus. Although Zn\(^{2+}\) is a critical cofactor for more than 2000 transcription factors and 300 enzymes, regulating cell differentiation, proliferation, and basic metabolic functions of the cells, the molecular mechanisms of Zn\(^{2+}\) transport and the physiological role of Zn\(^{2+}\) store in megakaryocyte and platelet function remain elusive. In this review, we summarize the contribution of extracellular or intracellular Zn\(^{2+}\) to megakaryocyte and platelet function and discuss the consequences of dysregulated Zn\(^{2+}\) homeostasis in platelet-related diseases by focusing on thrombosis, ischemic stroke and storage pool diseases.
KW  - Zinc
KW  - platelets
KW  - hemostasis
KW  - thrombosis
KW  - ischemic stroke
KW  - storage-pool diseases
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-285554
SN  - 1422-0067
VL  - 20
IS  - 21
ER  - 
TY  - JOUR
A1  - Gotru, Sanjeev Kiran
A1  - van Geffen, Johanna P.
A1  - Nagy, Magdolna
A1  - Mammadova-Bach, Elmina
A1  - Eilenberger, Julia
A1  - Volz, Julia
A1  - Manukjan, Georgi
A1  - Schulze, Harald
A1  - Wagner, Leonard
A1  - Eber, Stefan
A1  - Schambeck, Christian
A1  - Deppermann, Carsten
A1  - Brouns, Sanne
A1  - Nurden, Paquita
A1  - Greinacher, Andreas
A1  - Sachs, Ulrich
A1  - Nieswandt, Bernhard
A1  - Hermanns, Heike M.
A1  - Heemskerk, Johan W. M.
A1  - Braun, Attila
T1  - Defective Zn2+ homeostasis in mouse and human platelets with α- and δ-storage pool diseases
JF  - Scientific Reports
N2  - 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.
KW  - coagulation system
KW  - metals
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227455
VL  - 9
ER  -