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

Area of Science:

• Forensic Science
• Biochemistry
• Pathology

Background:

• Accurate postmortem interval (PMI) estimation is vital in forensic investigations.
• Current methods for determining time of death face significant challenges in forensic medicine.
• Protein analysis and histopathology offer potential avenues for improved PMI assessment.

Purpose of the Study:

• To evaluate the utility of protein analysis and histopathological examination for estimating the postmortem interval (PMI).
• To assess changes in specific protein expressions (β-catenin and Bcl-2) in rat organs over time postmortem.
• To correlate histopathological degradation patterns with increasing PMI.

Main Methods:

• Fifty male rats were divided into five groups and organs (kidneys, liver) were collected at 0, 24, 48, 72, and 96-hour intervals postmortem.
• Immunohistochemical analysis was performed for β-catenin expression.
• Flow cytometry was used to measure Bcl-2 expression.
• Histopathological examination of liver and kidney tissues was conducted.

Main Results:

• β-catenin immunoreactivity increased significantly from 0 to 96 hours postmortem in both organs.
• Bcl-2 expression in the liver and kidney decreased over the 96-hour postmortem period.
• Histopathological analysis revealed progressive tissue degradation and loss of normal architecture in liver and kidney tissues with increasing PMI.

Conclusions:

• Alterations in specific protein autolysis, such as β-catenin and Bcl-2, show potential as diagnostic markers for PMI estimation.
• Autolytic processes demonstrate a delayed onset and accelerated progression rate.
• Organ-specific differences in autolysis rates exist, influenced by tissue structure and enzymatic content, warranting further investigation for human application.