Forensic Proteomics for the Discovery of New post mortem Interval Biomarkers: A Preliminary Study

Abstract

Estimating the time since death (<i>post mortem</i> interval, PMI) represents one of the most important tasks in daily forensic casework. For decades, forensic scientists have investigated changes in <i>post mortem</i> body composition, focusing on different physical, chemical, or biological aspects, to discover a reliable method for estimating PMI; nevertheless, all of these attempts remain unsuccessful considering the currently available methodical spectrum characterized by great inaccuracies and limitations. However, recent promising approaches focus on the <i>post mortem</i> decomposition of biomolecules. In particular, significant advances have been made in research on the <i>post mortem</i> degradation of proteins. In the present study, we investigated early <i>post mortem</i> changes (during the first 24 h) in the proteome profile of the pig skeletal muscle looking for new PMI specific biomarkers. By mass spectrometry (MS)-based proteomics, we were able to identify a total of nine potential PMI biomarkers, whose quantity changed constantly and progressively over time, directly or inversely proportional to the advancement of <i>post mortem</i> hours. Our preliminary study underlines the importance of the proteomic approach in the search for a reliable method for PMI determination and highlights the need to characterize a large number of reliable marker proteins useful in forensic practice for PMI estimation.