is overexpressed in human cardiac tissue in hypothermia deaths; associations between the transcript and stress hormone levels in cardiac deaths.

BACKGROUND

Amphiregulin (AREG) is a growth factor linked to cardioprotection and heart pathology during myocardial stress. Our aim was to investigate cardiac expression, its potential as a postmortem hypothermia marker and its possible stress hormone dependency in different types of deaths.

MATERIALS AND METHODS

Heart RNA was isolated from hypothermic, cardiac and non-cardiac deaths. Relative mRNA levels and urine stress hormone concentrations were measured by qPCR and enzyme-linked immunosorbent assays from eight different death cause groups. Receiver operating characteristic curve was used to evaluate a cut-off point for expression as a hypothermia marker. Regulatory elements were predicted by PROMO.

RESULTS

The mRNA levels were significantly higher in hypothermic deaths than in most cardiac and non-cardiac deaths. expression indicated hypothermic deaths with nearly 70% sensitivity and specificity. However, high expression levels were also detected in non-ischaemic deaths. The highest concentrations of adrenaline and cortisol were detected in hypothermic deaths, while the highest noradrenaline concentrations associated with atherosclerotic heart disease (AHD) deaths with acute myocardial infarction and trauma deaths. There were no significant correlations between stress hormones and mRNA in hypothermic and non-cardiac deaths, whereas moderate-to-high associations were detected in cardiac deaths. Putative response elements for cortisol and catecholamines were found in .

CONCLUSIONS

Severe hypothermia activates cardiac expression practicable as a postmortem hypothermia marker. Cortisol and catecholamines may act as transcriptional modifiers of this gene, especially in long-term ischaemic heart disease. However, the exact role of these hormones in upregulation of during hypothermia remains unclear.