The hysteresis damage of cold exposure on tissue and transcript levels in mice

Objectives: Although cold stress -induced damage to the heart and thyroid has been reported, specific organ associations between the heart and thyroid with delayed injury mechanisms have not been investigated. In this study, we determined the damage time and transcript levels of a large number of genes in the heart and thyroid after cold exposure. Meanwhile, we analysed the relationship between heart and thyroid injury in human medical records to determine the association of delayed injury from cold exposure. Methods: Mice were exposed to cold stress and hysteresis injury. Gene changes at the transcriptional level were detected using high throughput sequencing technology. The most variable genes were verified at the protein level using Western Blotting and medical records were collected and analysed. Results: The damage was the most severe when the animals were allowed to recover to room temperature for 4 h after exposure to cold stress. During this process, STAT1 and ATF3 genes were acutely up -regulated. Analysis of human medical records showed the highest correlation between AST and T4 under cold stress (p = 0.0011). Conclusions: Exposure to cold increases blood level of free thyroid hormone and biomarkers of myocardial injury, as well as related mRNA levels. These changes were more pronounced after return to room temperature.