Abstract
<jats:p>Hypothermic storage is constrained by the progressive depletion of energy reserves, curtailing the shelf-life of organs, cell therapies, and blood products. High sub-zero supercooling helps preserve energy homeostasis by slowing catabolic processes; however, the resulting injury in this setting is not primarily driven by energy depletion. Here, we investigated whether low-dose ethanol could prevent forms of injury that arise independently of disrupted energy homeostasis and remain unaddressed in supercooled storage. Human red blood cells treated with 4% (v/v) ethanol were stored 4 C, −4 C, or −8 C and subject to a series of functional assessments and integrated metabolomic/lipidomic profiling after 21 and 42 days of storage. Metabolomics data showed that energy homeostasis was better preserved at lower temperatures, yet these supercooled conditions simultaneously intensified hemolysis and caused a marked depletion of lysophospholipid species that did not occur at 4 C. Ethanol blunted these effects, cutting hemolysis by ~50 % at −4 C, by ~85 % at −8 C, and attenuating lysophospholipid depletion. These results uncover a previously unrecognized, lipid-centric injury that arises during supercooled storage and establish low-dose ethanol as a simple, readily deployable countermeasure that could help extend storage intervals of diverse biological systems.</jats:p>