Exposure to very low temperatures can lead to tissue damage (“frostbite”), particularly in the skin. Over time, it can also have systemic, sometimes life-threatening effects on the body. This can be a problem, e.g., for military personnel working under extreme weather conditions, travelers or athletes in cold regions, or workers exposed to subzero temperatures on the job. Preventing skin damage can involve, e.g., heated garments and/or the application of antifreeze agents. However, the latter is challenging to use safely due to the often toxic nature of synthetic antifreeze compounds.

Munia Ganguli, CSIR−Institute of Genomics and Integrative Biology, New Delhi, India, and Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India, and colleagues have developed an optimized combination of dimethyl sulfoxide (DMSO) and poly(vinyl alcohol) (PVA) that can be applied to skin cells or tissue to provide protection from cold damage. DMSO cannot be used alone due to its toxicity in high concentrations. PVA, in contrast, has a better biocompatibility. DMSO can penetrate cells and protect them from cold damage, while PVA can inhibit the growth of extracellular ice crystals.

Using a cell viability assay, the researchers found that a combination of 2 % DMSO and 1.6 mg/mL PVA was most promising. Cells with this mixture pre-applied were able to withstand temperatures of –20 °C for one hour and resume their normal cell cycle after thawing out. In a mouse experiment, the team mixed their optimized combination of cryopreservative agents into a cream and found that applying the resulting mixture to the skin before a cold challenge reduced skin damage. Multiple applications did not compromise the skin integrity. According to the team, the results could help to develop antifreeze creams for topical use in the future.

• A Combination of Synthetic Molecules Acts as Antifreeze for the Protection of Skin against Cold-Induced Injuries,
  Aanchal Gupta, Betsy Reshma G, Praveen Singh, Ekta Kohli, Shantanu Sengupta, Munia Ganguli,
  ACS Appl. Bio Mater. 2021.
  https://doi.org/10.1021/acsabm.1c01058