Preliminary findings suggest a topical ‘antifreeze’ could protect the skin from frostbite and other cold injuries.
In a paper published in ACS Applied Bio Materials (Jan. 17, 2022, 5(1):252–264), the authors note that existing therapies for cold injuries halt the progression of the injury but do not prevent it. As well, prophylactic measures such as electric heaters sewn into clothing or transgenic antifreeze proteins are often costly, impractical or have safety concerns.
To explore the possibility of a convenient, inexpensive prophylactic for cold injuries, the researchers tested the frostbite prevention properties of a combination of synthetic molecules commonly used in labs to cryopreserve cells. The two molecules are dimethyl sulfoxide (DMSO), which keeps ice crystals from forming inside cells, and polyvinyl alcohol (PVA), which prevents ice crystals in the spaces between cells. They named the combination SynAFP.
In vitro studies of SynAFP revealed improved cellular revival and cell viability, retention of the cytoskeleton, and normal cell cycle progression even after cold stress.
Animal model tests showed that pre-application of SynAFP in mice facing a frostbite challenge prevented their skin from incurring significant injury. Multiple applications of SynAFP on mouse skin at room temperature also did not compromise skin integrity, which suggested the agent was relatively safe.
Formulating SynAFP into an Aloe vera-based cream resulted in similar protection under cold stress conditions in the animal models, preventing cold injury if applied 15 minutes before a cold challenge. The cream reduced frostbite wound size, tissue damage and inflammation, and sped healing, compared with no treatment. However, the cream did not prevent frostbite when applied 30 minutes or more before the cold challenge.
The authors write that the effects of the antifreeze cream in humans, and how frequently it needs to be reapplied, must still be determined.