Abstract
BACKGROUND: Long-duration space missions beyond low Earth orbit pose increased risks of injury to astronauts. Traumatic hemorrhage will be a cause of preventable death. Due to payload constraints, in situ production of medical materials is essential. Regolith from the Moon, Mars, and asteroids is rich in silicates, which may serve as a hemostatic agent. OBJECTIVES: Here, we aimed to evaluate whether extraterrestrial regolith simulants, their mineral components, and meteorites can activate coagulation through factor (F)XII and control bleeding. METHODS: The procoagulant potential of Lunar and Martian regolith simulants, their component silicate minerals, and meteorite samples was assessed in vitro. Plasma clotting turbidity, thrombin generation, and FXIIa chromogenic assays were performed using either normal or FXII-inhibited/immunodepleted human plasma. ζ Potential and SiO(2) content were also plotted against time to fibrin clot formation. The in vivo efficacy of Lunar highland simulant (CSM-LHT-1), Mars global simulant high clay (CSM-MGS-1C), and Northwest Africa-869 chondritic meteorite was assessed in a pilot study using a porcine model of penetrating hemorrhage. RESULTS: All extraterrestrial regolith simulant samples accelerated clotting, thrombin generation, and FXII activation in normal plasma, with reduced effects in FXII-immunodepleted or FXII-inhibited plasma. Phyllosilicates showed greater procoagulant activity than framework silicates. In vivo, wounds treated with regolith remained clotted longer and lost less blood than wounds treated with gauze alone, with the Northwest Africa-869 chondrite meteorite significantly improving clotting and reducing blood loss. CONCLUSION: Extraterrestrial regolith activated coagulation in a FXII-dependent manner and reduced blood loss in a trauma model of penetrating hemorrhage. This suggests that extraterrestrial regolith may be used as a hemostatic agent during space missions.