Anticoagulation targeting membrane-bound anionic phospholipids improves outcomes of traumatic brain injury in mice

Abstract

Severe traumatic brain injury (TBI) often causes an acute systemic hypercoagulable state that rapidly develops into consumptive coagulopathy. We have recently demonstrated that TBI-induced coagulopathy (TBI-IC) is initiated and disseminated by brain-derived extracellular vesicles (BDEVs) and propagated by extracellular vesicles (EVs) from endothelial cells and platelets. Here, we present results from a study designed to test the hypothesis that anticoagulation targeting anionic phospholipid-expressing EVs prevents TBI-IC and improves the outcomes of mice subjected to severe TBI. We evaluated the effects of a fusion protein (ANV-6L15) for improving the outcomes of TBI. ANV-6L15 combines the phosphatidylserine (PS)-binding annexin V with a peptide anticoagulant modified to preferentially target extrinsic coagulation. We found that ANV-6L15 reduced intracranial hematoma by 70.2%, improved neurological function, and reduced death by 56.8% in mice subjected to fluid percussion injury at 1.9 atm. It protected the TBI mice by preventing vascular leakage, tissue edema, and the TBI-induced hypercoagulable state. We further showed that the extrinsic tenase complex was formed on the surfaces of circulating EVs, with the highest level found on BDEVs. Phospholipidomic analysis detected the highest levels of PS on BDEVs, as compared to EVs from endothelial cells and platelets (79.1, 15.2, and 3.5 nM/mg of protein, respectively). These findings demonstrate that TBI-IC results from a trauma-induced hypercoagulable state and may be treated by anticoagulation targeting on the anionic phospholipid-expressing membrane of EVs from the brain and other cells.

Trauma-Derived Extracellular Vesicles Are Sufficient to Induce Endothelial Dysfunction and Coagulopathy

“…For examples, EVs from endothelial cells, smooth muscle cells, and monocytes contain tissue factors critical for injury-induced coagulation cascade, whereas those from platelets contain low or no tissue factor (24). Furthermore, levels of the membrane anionic phospholipids such as phosphatidylserine can also differ on EVs from different parental cells (25). Distinguishing cell type–specific EVs is important because severe trauma and HS could cause larger and deeper tissue injuries, releasing more tissue factor-bearing EVs.…”

Extracellular vesicles as bioactive nanotherapeutics: An emerging paradigm for regenerative medicine

“…In addition to being widely used as native therapeutic agents for neuroregeneration, EVs have also been engineered to transport various cargo for neurological repair 163 , 164 . Kim's group designed a biocompatible magnetic nanovesicle (MNV) by a serial extrusion of iron oxide nanoparticles (IONP)-loaded MSC to greatly enhance the therapeutic outcome against ischemic stroke ( Figure 6 B ) 165 .…”

Cell-Derived Exosomes as Therapeutic Strategies and Exosome-Derived microRNAs as Biomarkers for Traumatic Brain Injury

“…Surprisingly, a research team working on coagulopathy after TBI revealed that lactadherin might prevent coagulopathy and improve the survival of severe TBI mice via promoting BD-MVs clearance [ 128 ]. Moreover, coagulopathy after TBI may also be treated by anticoagulation-targeting membrane-bound anionic phospholipids of BD-EVs to improve TBI outcomes [ 129 ].…”