Protective effects of plasma products on the endothelial-glycocalyx barrier following trauma-hemorrhagic shock: is sphingosine-1 phosphate responsible?

Plasma is an important component of resuscitation after trauma and hemorrhagic shock (T/HS). The specific plasma proteins and the impact of storage conditions is uncertain. Utilizing a microfluidic device system, we studied the effect of various types of plasma on the endothelial barrier function following T/HS.Human umbilical vein endothelial cells (HUVEC) were cultured in microfluidic plates. The microfluidic plates were subjected to control or shock conditions (hypoxia/reoxygenation+ epinephrine, 10 μM). Fresh plasma, one day thawed plasma, five-day thawed plasma and lyophilized plasma were then added. Supplementation of sphingosine-1 phosphate (S-1P) was done in a subset of experiments. Effect on the endothelial glycocalyx was indexed by shedding of syndecan-1, and hyaluronic acid. Endothelial injury/activation was indexed by soluble thrombomodulin (sTM), tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1). Vascular permeability determined by the ratio of angiopoetin-2 to angiopoetin-1 (ang-2/1). Concentration of S-1P and adiponectin in the different plasma groups was measured.HUVEC exposed to shock conditions increased shedding of syndecan-1 and hyaluronic acid. Administration of the various types of plasma decreased shedding, except for 5-day thawed plasma. Shocked HUVEC cells demonstrated a profibrinolytic phenotype, this normalized with all plasma types except for 5-day thawed plasma. The concentration of S-1P was significantly less in the 5-day thawed plasma compared to the other plasma types. Addition of S-1P to 5-day thawed plasma returned the benefits lost with storage CONCLUSION: A biomimetic model of the microcirculation following T/HS demonstrated endothelial glycocalyx and endothelial cellular injury/activation as well as a profibrinolytic phenotype. These effects were abrogated by all plasma products except the 5-day thawed plasma. Plasma thawed > 5 days had diminished S1-P concentrations. Our data suggest that S1-P protein is critical to the protective effect of plasma products on the endothelial-glycocalyx barrier following T/HS.Basic Science.