Related Experiment Video
Updated: Aug 3, 2026
Comprehensive Autopsy Program for Individuals with Multiple Sclerosis
Published on: July 19, 2019
A miRNome analysis at the early postmortem interval
Mariano Guardado-Estrada1, Christian A Cárdenas-Monroy1, Vanessa Martínez-Rivera1
1Laboratorio de Genética, Ciencia Forense, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico.
Abstract:
The postmortem interval (PMI) is the time elapsing since the death of an individual until the body is examined. Different molecules have been analyzed to better estimate the PMI with variable results. The miRNAs draw attention in the forensic field to estimate the PMI as they can better support degradation. In the present work, we analyzed the miRNome at early PMI in rats' skeletal muscle using the Affymetrix GeneChip™ miRNA 4.0 microarrays. We found 156 dysregulated miRNAs in rats' skeletal muscle at 24 h of PMI, out of which 84 were downregulated, and 72 upregulated. The miRNA most significantly downregulated was miR-139-5p (FC = -160, p = 9.97 × 10-11), while the most upregulated was rno-miR-92b-5p (FC = 241.18, p = 2.39 × 10-6). Regarding the targets of these dysregulated miRNAs, the rno-miR-125b-5p and rno-miR-138-5p were the miRNAs with more mRNA targets. The mRNA targets that we found in the present study participate in several biological processes such as interleukin secretion regulation, translation regulation, cell growth, or low oxygen response. In addition, we found a downregulation of SIRT1 mRNA and an upregulation of TGFBR2 mRNA at 24 h of PMI. These results suggest there is an active participation of miRNAs at early PMI which could be further explored to identify potential biomarkers for PMI estimation.
Insights
Researchers analyzed microRNAs (miRNAs) in rat skeletal muscle to estimate early postmortem intervals (PMI). They identified 156 dysregulated miRNAs, suggesting their potential as reliable biomarkers for forensic science.
Area of Science:
- Forensic Science
- Molecular Biology
- Genomics
Background:
- Estimating the postmortem interval (PMI) is crucial in forensic investigations.
- MicroRNAs (miRNAs) show promise as biomarkers due to their stability.
- Previous studies have explored various molecules for PMI estimation with variable success.
Purpose of the Study:
- To investigate the miRNome in rat skeletal muscle at early postmortem intervals (PMI).
- To identify potential miRNA biomarkers for estimating early PMI.
- To explore the role of miRNAs in biological processes following death.
Main Methods:
- Analysis of the miRNome in rat skeletal muscle using Affymetrix GeneChip™ miRNA 4.0 microarrays.
- Quantification and statistical analysis of differentially expressed miRNAs at 24 hours postmortem.
- Bioinformatic analysis to identify mRNA targets of dysregulated miRNAs.
Main Results:
- 156 miRNAs were found to be dysregulated in rat skeletal muscle at 24 h PMI (84 downregulated, 72 upregulated).
- Significant changes observed in specific miRNAs, including miR-139-5p (downregulated) and rno-miR-92b-5p (upregulated).
- Identified mRNA targets involved in crucial biological processes like cell growth and response to low oxygen; observed changes in SIRT1 and TGFBR2 mRNA levels.
Conclusions:
- MicroRNAs are actively involved in biological processes during early postmortem intervals.
- Dysregulated miRNAs in skeletal muscle show potential as biomarkers for early PMI estimation.
- Further research into miRNA profiles could enhance forensic science capabilities for determining time since death.
