Serial analyses of postmortem changes in human skeletal muscle: A case study of alterations in proteome profile, histology, electrolyte contents,water composition, and enzyme activity

摘要

Postmortem tissues are frequently used in forensic investigation, clinical studies, and biomedical research. It is well known that the shorter period from death to analyses provides the more accurate results.However, the longest postmortem interval that still provides the reliable data remains unclear. We performed serial analyses of postmortem changes in proteome profile, histology, electrolyte contents, water composition, and enzyme activity in human vastus lateralis muscle from amale cadaver (died from amotorcycle accident). This uninjuredmusclewas sectioned into several 1-cm3cubes and stored in individual closed tubes at 4 or 257Cfor 0, 2, 4, 6, 12, 24 or 48 h prior to proteomic, histological, chemical and biochemical analyses. At 47C, the 2-DE proteome profile remained unchanged until 24 h, when some poorly focused protein spots and significant decrease in the total number of visualized spotswere observed. These changeswere detectable earlier (12 h) in the samples stored at 257C. Profound vacuolization and autolysis started at 24 and 6 h for the samples stored at 47C and 257C, respectively. K andMg contents began to increase at 12 and 48 h, respectively, for both temperatures. However, the increase in Na and Ca contents began at 24 h in the samples stored at 47C, but started earlier (12 h) in those stored at 257C. Water content started to decline at 48 and 24 h in the samples stored at 4 and 257C, respectively. Muscle lactate dehydrogenase activity began to be out of range at 12 h for both temperatures. These findings demonstrate that storing the samples at 47C could delay some of the aforementioned changes, which occurred more rapidly at 257C. Our results also suggest thatmuscle proteome profile, histology, electrolyte contents, water composition, and enzyme activity should be analyzedwithin the optimal postmortemintervals,which vary among individual analyses, to obtain themost reliable data.