Shear Stress Accumulation Enhances von Willebrand Factor-Induced Platelet P-Selectin Translocation in a PI3K/Akt Pathway-Dependent Manner

Abstract

Platelet adhesion and activation through the interaction of von Willebrand factor (VWF) with platelet glycoprotein (GP) Ibα are the early key events in hemostasis and thrombosis especially under high blood shear stress. P-selectin translocation from α granule to the cell surface is a typical platelet function phenotype, which makes the platelet-induced inflammatory response of flowing leukocytes possible and can be induced by either chemical agonists (thrombin, ADP, etc.) or high blood shear stress, but regulations of VWF mutation and blood shear stress on VWF-induced P-selectin translocation remain unclear. With flow cytometry, parallel plate flow chamber, and immunofluorescence staining techniques, we examined the P-selectin translocation of platelets on immobilized wild-type (WT) VWF-A1 domain and its two mutants, the gain-of-function (GOF) mutant R1308L and the loss-of-function (LOF) mutant G1324S, respectively. The results showed that the VWF-A1-induced platelet P-selectin translocation was triggered, accelerated, and enhanced by fluid shear stress and could be correlated with shear stress accumulation (SSA, the product of fluid shear stress and mechanical stimulus time), and the PI3K/Akt axis was involved in the platelet P-selectin translocation. The force-triggered P-selectin translocation occurred quickly on partial platelet surface first and then extended gradually to the whole platelet surface as SSA increased. The P-selectin translocation process would be promoted by the GOF mutation (R1308L) but slowed down by the LOF mutation (G1324S). These findings demonstrated a force-enhanced regulation mechanism for the VWF-induced platelet P-selectin translocation through the PI3K/Akt pathway and provided a novel insight into the mechano-chemical regulation mechanism for the key events, such as platelet activation and functional phenotype change in hemostasis and thrombosis.

Nanoenzyme engineered neutrophil-derived exosomes attenuate joint injury in advanced rheumatoid arthritis via regulating inflammatory environment

“…Of note, their down-regulation indicated anti-inflammatory effects of uPB-Exo. Collected evidences have shown that the downregulated genes, including colony stimulating factor 3 [ 75 ], matrix metallopeptidase 9 [ 76 ], interleukin 1 alpha [ 77 ], interleukin 1 beta [ 78 ], interleukin 7 receptor [ 79 ] and Von Willebrand factor [ 80 ] could be regulated by PI3K/AKT pathway. Meanwhile, KEGG pathway enrichment analysis demonstrated that numerous down-regulated genes were significantly enriched PI3K-Akt pathway in FLS with uPB-Exo treatment ( Fig.…”

ATRA treatment slowed P-selectin-mediated rolling of flowing HL60 cells in a mechano-chemical-dependent manner

“…A total of 1 × 10 6 #/ml HL60 cells or neutrophils were washed with PBS three times, blocked with 2% BSA, and stained, respectively, with PE-labeled anti-CD11a, PE-labeled anti-CD11b, and PE-labeled anti-CD162 antibodies (BD Bioscience, USA) for 30 min at 4°C in the dark as described previously ( 51 ). Then, the cells were washed three times with PBS and analyzed by flow cytometry (BD Accuri C6, BD, USA) with a minimum acquisition of 10,000 events.…”

Patient specific approach to analysis of shear-induced platelet activation in haemodialysis arteriovenous fistula

“…VWF unfolding is supposedly initiated under overcritical cumulative shear stress [ 26 ]. The subsequent binding of VWF multimers with platelet GPIb receptors triggers outside-in signalling, i.e., platelet priming [ 47 , 48 ]. Platelet priming leads to platelet activation at which conspicuous functional consequences (e.g., P-selection expression) are observed [ 19 ].…”