Gene expression changes reveal the impact of the space environment on the skin of International Space Station astronauts.

This article investigates the impact of the space environment on the skin of International Space Station astronauts by analyzing gene expression changes in hair follicle tissue before, during, and after space missions. Using bioinformatics tools on publicly available gene expression data from 10 astronauts, the study identified 554 genes with altered expression patterns, notably 311 genes upregulated during spaceflight and downregulated upon return to Earth. These genes are primarily involved in skin development, keratinocyte differentiation, and cornification, suggesting that space conditions affect skin barrier integrity and inflammatory responses. Ten key skin-related hub genes, nine transcription factors, and three circadian rhythm-related genes were highlighted, with most gene expression changes reversing after return to Earth. The findings imply that factors such as space radiation and microgravity influence skin keratinocyte differentiation and barrier function, with potential implications for astronaut health during long-duration missions.