Postmortem interval estimation based on protein analysis and marker studies in different organs in vivo

Estimating the postmortem interval (PMI) is a crucial aspect of forensic death-related investigations. However, determining the time of death remains one of the biggest challenges in forensic medicine. This study aims to assess the potential of protein analysis as a vital tool and histopathological examination to evaluate the PMI. Fifty male rats were randomly distributed into five groups of 10. These rats were kept at room temperature (22 °C) with a relative humidity of 15% during the period between the time of death and organ removal. The kidneys and Livers were extracted at 0-, 24-, 48-, 72-, and 96-hour intervals. The β-catenin immunohistochemical analysis showed no immunoreactivity in either organ at 0 h, which increased to severe immunoreactivity at 96 h after death. Additionally, flow cytometry demonstrated a decline in liver and kidney Bcl-2 expression at 96 h, at 17.5% and 12.8%, respectively, as the postmortem period increased. Moreover, a histopathological examination of the Liver and kidney showed progressively greater degradation over time as the PMI increased, resulting in the loss of normal Liver and kidney architecture at 96 h. These findings suggest the potential use of specific proteins' autolytic alterations as definite diagnostic parameters for the PMI. Autolytic processes have a delayed onset and show a significant increase in progression rate at each time interval. Different organs suffer different rates of autolysis in correlation to their structure and enzymatic content. Further studies are required to evaluate the definite roles of β-catenin and Bcl-2 expression as predictive tools for future applications in humans based on extensive experimental studies.