The effect of elapsed time on Cardiac Troponin-T (cTnT) degradation and its dependency on the cause of death

• Published in: Journal of forensic and legal medicine Vol. 40; pp. 16 - 21
• Main Authors: Kumar, Sachil, Ali, Wahid, Bhattacharya, Sandeep, Verma, Anoop K
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-05-2016; Churchill Livingstone Inc., Medical Publishers
• Subjects: Asphyxia; Asphyxia - blood; Biomarkers - blood; Blotting, Western; Burn; Burns - blood; Case-Control Studies; Cause of death; Degradation; Electric Injuries - blood; Electrocution; Electrocutions; Forensic Pathology; Humans; Molecular weight; Myocardial Infarction - blood; Pathology; Poisoning; Poisoning - blood; Postmortem Changes; Proteins; Suffocation; Time Factors; Troponin T - blood; Burn; Degradation; Forensic Medicine; Electrocution; Poisoning; Asphyxia; MI; Cause of death
• ISSN: 1752-928X; 1878-7487
• DOI: 10.1016/j.jflm.2016.02.002

Abstract Purpose The aim of the present study is to evaluate the effect of elapsed time on cardiac troponin-T degradation and its dependency on the cause of death. Methods The cases included in this study were divided into six groups depending upon the cause of death without any prior history of disease that died in the hospital and their exact time of death was known. The analysis involves extraction of the protein, separation by denaturing gel electrophoresis and visualization by Western blot. Results Western blot data shows the rate of degradation of cTnT into lower molecular weight fragments with respect to time. In cases of control group the greatest amount of protein breakdown was observed within the first 64 hrs while in MI cases within first 6 hours, the original band of cTnT (42 kDa) decreased markedly into seven major fragments, with 25 kDa & 20 kDa fragments being the most prominent. In burn group, at 41.40 hours blot shows maximum fragmentation. In electrocution group the greatest amount of protein breakdown was observed within the first 50 Hrs. Within asphyxia cases, the original band of cTnT (42 kDa) decreased markedly into many major and minor fragments which continues up to 210 Hrs while the original band of cTnT (42 kDa) in poisoning cases decreased markedly into many major & minor fragments up to 140 hrs but after it blot shows only intact protein of very less intensity with few minor fragments. Conclusion It can be observed that in case of death due to MI, the intact cTnI fragmented at a much faster rate than in burn, electrocution, control, poisoning and asphyxia group. Thus, the rate of fragmentation of intact cTnT into lower molecular weight fragments depends upon the cause of death.