Role of ERK1 and ANP as potential forensic biomarkers in hypothermia conditions: An experimental study

Diagnosing fatal hypothermia remains a forensic challenge due to the lack of specific postmortem markers. This study investigates the potential of extracellular signal-regulated kinase 1 (ERK) and atrial natriuretic peptide (ANP) as biochemical indicators in hypothermia-related deaths, particularly under the influence of ethanol and diazepam. A randomized experimental study was conducted in rats approximately 3.5 months old and weighing 200–240 grams, which were randomized into the control group (n=7), the ethanol-treated group (n=7), and the diazepam-treated group (n=7). Survival time was measured from the point of immersion in 7°C water until the animals’ death. Hypothermia was induced, and serum and muscle levels of ERK1 and ANP were measured using ELISA. Serum ERK1 levels differed significantly across groups (p = 0.039), with a similar changes in Control and Ethanol groups, while Diazepam decreased. ANP levels showed no significant changes across groups or time points. Muscle concentrations of both markers remained stable. The observed alterations in ERK1 levels may indicate a possible association with stress responses during hypothermia, although the findings should be considered exploratory due to limited statistical significance after multiple-comparison correction. ANP showed limited diagnostic utility under the study conditions. Further research incorporating histological validation and larger cohorts is needed to confirm these findings and improve forensic applications.