The role of miRNA-21 and hypoxia inducible factor-1 in predicting post mortem interval in cardiac muscles of aluminum phosphide deaths

Background: The assessment of the postmortem interval (PMI) represents one of the major challenges in forensic pathology. Because of their stability, microRNAs, or miRNAs, are anticipated to be helpful in forensic research. Objective: To see if estimation of PMI is possible using miRNA-21 and Hypoxia-inducible factor-1 alpha (HIF-1 alpha) expression levels in the heart samples from aluminum phosphide toxicity (Alpt). Methods: This was a cross sectional study on 60 post-mortem samples (heart tissues) collected at different intervals during forensic autopsies. The two groups were allocated equally according to the cause of death into Group I (non-toxicated deaths, n = 30): Deaths caused by other than toxicity, and Group II (toxicated deaths, n = 30): Deaths due to Alpt. MDA (Malondialdehyde) and GSH (Glutathione), were measured in heart tissues using ELIZA. MiRNA- 21and HIF-1 alpha expression levels were measured in heart tissues at different PMI using RT-Q PCR. ROC curve for detection of toxicated deaths using miRNA-21 and HIF was carried out. Results: miRNA-21 and HIF-1 alpha expression levels in Alp deaths were up regulated while GSH was downregulated with statistically significant difference. There was positive correlation between miRNA-21, HIF-1 alpha and MDA with PMI while there was negative correlation between GSH and PMI in Alp deaths. In prediction of post mortem interval in Alp deaths miRNA-21 sensitivity and specificity were (75.9 %, 51.7 %, respectively) while HIF-1 alpha sensitivity and specificity were 100 %. Conclusion: PMI can be calculated using the degree to which particular miRNA-21 and HIF-1 alpha are expressed in the heart tissue. The combination of miRNA-21 with HIF-1 alpha in post mortem estimation is precious indicators.