Temporal mRNA and miRNA expression signatures as molecular markers of incised wound age and vitality

Background A precise wound age estimation remains a significant challenge in forensic pathology, with critical implications in crime scene reconstruction, determination of wound vitality, and medicolegal interpretation. Traditional histopathology has limited sensitivity in the early post-injury period, prompting exploration of objective molecular approaches. This study investigated the temporal expression patterns of TNF-α and VEGF mRNAs together with miRNA-29a, miRNA-15b, and miRNA-125b in experimentally induced incised skin wounds and evaluated their utility for wound aging and vitality assessment. Incised wounds were inflicted in rats’ skin and sampled at multiple time points (0 h to 10 days post-injury). Total RNA was extracted and analyzed using reverse transcription quantitative polymerase chain reaction (RT-qPCR). Expression profiles of mRNA and miRNA markers were compared among wound-age groups and between antemortem and postmortem wounds using appropriate statistical analyses. Results TNF-α mRNA remained upregulated throughout healing, whereas VEGF mRNA showed a distinct biphasic pattern: early suppression, peak overexpression at 24 h, and a sustained rebound. miRNA-29a showed bimodal expression with peaks at 12 h and 7–10 days. miRNA-15b and miRNA-125b were predominantly downregulated. For early wound-age estimation (0–24 h), multivariate linear regression modeling demonstrated that all tested markers, except TNF-α, accounted for 84.7% of total variance (R 2 = 0.847, p < 0.001), with VEGF showing the strongest independent association. Significant differences between antemortem and postmortem groups were observed for VEGF, miRNA-15b, and miRNA-125b. ROC analysis validated miRNA-125b as the top diagnostic indicator (AUC = 0.917), followed closely by VEGF (AUC = 0.889) and miRNA-15b (AUC = 0.861). Significant associations were also observed among mRNA–miRNA markers across different wound-healing time points, suggesting potential regulatory interactions. Conclusions This exploratory study of mRNA and miRNA temporal expression profiles provides an objective molecular approach for potential wound age estimation and vitality assessment, offering enhanced precision over traditional methods, especially early post-infliction.