ATF3 mRNA, but not BTG2, as a possible marker for vital reaction of skin contusion

Vitality markers in forensic investigations: a literature review

Determining whether an injury was sustained in life or not is one of the most important topics in forensic medicine. Morphological, cytological, and biological techniques are used to assess wound vitality. Several markers involved in vital and supravital reactions increase the accuracy of wound age estimation. This systematic review aimed to investigate the main vitality markers used in forensic medicine to date. This review was conducted by performing a systematic literature search on online resources (PubMed Central database and Google Scholar) until May 2022. We identified 46 articles published between 1987 and May 2022, analyzing a total of 53 markers. Based on the data of this review, the most studied vitality markers were adhesion molecules (fibronectin, p-selectin, CD 15), pro-inflammatory cytokines (IL-6, IL-1β, TNF-α), cathepsin D, tryptase, and microRNAs (miRNAs). The most interesting studies were based on animal models: the different markers were investigated through immunohistochemical and qRT-PCR methods. The experimental methods were usually based on skin incisions, ligature marks, and burned skin areas. To date, it has not been possible to identify any gold standard markers based on the criteria of efficacy, specificity, and reliability; however, studies are still in progress. In the future, the use of miRNAs is promising as well as the combination of multiple markers. In this way, it will be possible to increase the sensitivity and specificity to validate systems or models for determining wound vitality in forensic practice.

FOXO3 Depletion as a Marker of Compression-Induced Apoptosis in the Ligature Mark: An Immunohistochemical Study

One of the most challenging issues in forensic pathology is lesion vitality demonstration, particularly in cases of hanging. Over the past few years, immunohistochemistry has been applied to this field with promising results. In particular, protein and transcription factors involved in the apoptotic process have been studied as vitality markers for the ligature mark. This study represents an implementation of our previous studies on ligature mark vitality demonstration. In this study, we evaluated the FOXO3 expression in post-mortem cervical skin samples through an immunohistochemical analysis. To evaluate FOXO3 expression, anti-FOXO3 antibodies (GTX100277) were used. The study group comprised 21 cases, 8 women and 13 men, whereas the control group consisted of 13 cases of subjects who died due to other causes. Decomposition and no clear circumstantial data were exclusion criteria. We found that FOXO3 is decreased in hanging cases compared with normal skin in other causes of death (p-value < 0.05). No differences were seen concerning the type of hanging material (hard or soft), type of hanging (complete or incomplete), and position of the knot. Our results suggest that FOXO3 depletion could be a valid immunohistochemical marker of ligature mark vitality.

mRNA microarray analysis for the identification of potential biomarkers for vital reaction in burned skin: a preliminary pilot study

The identification of ante- and post-mortem burns is challenging in forensic pathology. In this study, microarray analysis was used to detect the mRNA expression profiles in the skin of an experimental burn mouse model; the results were validated using RT-qPCR. Differentially expressed mRNAs (DE-mRNAs) were assessed using the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Our results revealed that mRNA expression of 501 genes was significantly different, of which 273 were upregulated and 228 were downregulated in ante-mortem burned mice skin. The expression levels of eight random mRNAs were consistent when measured using the microarray assay-based method and RT-qPCR. Genes from different functional categories and signalling pathways were enriched, including interleukin-20 binding, type IV hypersensitivity, negative regulation of acute inflammatory response, sensory organ development, endocytosis, neuroactive ligand-receptor interaction, and Jak-STAT signalling pathway. Only five of the eight mRNAs exhibited consistent changes in expression between burned skin samples of mice and human autopsy specimens. Our findings showed that DE-mRNAs revealed using microarray are potential biomarkers of ante-mortem burns. However, DE-mRNAs identified from experimental animal models cannot be directly extended to autopsy specimens without careful validation.

State-of-the-Art on Wound Vitality Evaluation: A Systematic Review

The vitality demonstration refers to determining if an injury has been caused ante- or post-mortem, while wound age means to evaluate how long a subject has survived after the infliction of an injury. Histology alone is not enough to prove the vitality of a lesion. Recently, immunohistochemistry, biochemistry, and molecular biology have been introduced in the field of lesions vitality and age demonstration. The study was conducted according to the preferred reporting items for systematic review (PRISMA) protocol. The search terms were "wound", "lesion", "vitality", "evaluation", "immunohistochemistry", "proteins", "electrolytes", "mRNAs", and "miRNAs" in the title, abstract, and keywords. This evaluation left 137 scientific papers. This review aimed to collect all the knowledge on vital wound demonstration and provide a temporal distribution of the methods currently available, in order to determine the age of lesions, thus helping forensic pathologists in finding a way through the tangled jungle of wound vitality evaluation.

Forensic Impact of the Omics Science Involved in the Wound: A Systematic Review

Background: In forensic autopsies, examining the wounds is one of the most critical aspects to clarify the causal relationship between the cause of death and the wounds observed on the corpse. However, on many occasions, it is difficult to differentiate antemortem injuries from post-mortem injuries, mainly when they occur very close to the moment of death. At present, various studies try to find biomarkers and clarify the molecular mechanisms involved in a wound due to the high variability of conditions in which they occur, thus being one of the most challenging problems in forensic pathology. This review aimed to study the omics data to determine the main lines of investigation emerging in the diagnosis of vital injuries, time of appearance, estimation of the age and vitality of the wound, and its possible contributions to the forensic field.

Methods: A systematic review of the human wound concerning forensic science was carried out by following PRISMA guidelines.

Results: This study sheds light on the role of omics research during the process of wounding, identifying different cytokines and other inflammatory mediators, as well as cells involved in the specific stage of the wound healing process, show great use in estimating the age of a wound. On the other hand, the expression levels of skin enzymes, proteins, metal ions, and other biomarkers play an essential role in differentiating vital and post-mortem wounds. More recent studies have begun to analyze and quantify mRNA from different genes that encode proteins that participate in the inflammation phase of a wound and miRNAs related to various cellular processes.

Conclusions: This study sheds light on the role of research in the molecular characterization of vital wounds, heralding a promising future for molecular characterization of wounds in the field of forensic pathology, opening up an important new area of research.

Systematic Review Registration: URL: https://www.crd.york.ac.uk/prospero/#myprospero, Identifier: CRD42021286623.

Wound Vitality in Decomposed Bodies: New Frontiers Through Immunohistochemistry

Background: The question about wound vitality and the estimation of wound age of production are two of the classic investigation fields of forensic sciences. To answer this, the techniques most frequently used in research studies are immunohistochemistry (IHC), molecular biology, and biochemistry. Despite the great data on the literature about the usefulness of IHC in forensic pathology, there is always a request for further studies, especially on tissues altered by putrefactive phenomena. In fact, the degradation of the tissues is intended as the main limiting factor to the use of this technique.

Scope: The aim of this pilot study was to evaluate the immunohistochemical behavior of samples collected from decomposed bodies (in different putrefaction phases) and to relate these findings to wound vitality and postmortem interval.

Materials and Methods: Samples of skin and soft tissues were collected during autopsies, which were executed on decomposed bodies, whose cause of death was concluded to be traumatic. An immunohistochemical study was performed using antibodies against CD15, CD45, IL-15, tryptase, and glycophorin-A MMPs (endopeptidases involved in degrading extracellular matrix proteins: MMP-9 and MMP-2). An immunohistochemistry (IHC) reaction was evaluated according to a qualitative method as the following legend: (0): not expressed, (+): isolated and disseminated expression, (++): expression in groups or widespread foci, and (+++): widespread expression.

Results: Most of the tested markers (tryptase, glycophorin, IL15, CD 15, CD 45, and MMP9) showed to be highly expressed in the tissue of putrefied skin for 15 days.

Discussion and Conclusion: Although certainly inconclusive, this experimental application demonstrated that a nonexclusive but combined use of multiple antibodies is appropriate to verify wound vitality in decomposed bodies. Among them, GPA exhibited major reliability.

Luteolin Alleviates Methamphetamine-Induced Hepatotoxicity by Suppressing the p53 Pathway-Mediated Apoptosis, Autophagy, and Inflammation in Rats

Misuse of the psychostimulant methamphetamine (METH) could induce serious hepatotoxicity. Our previous study revealed the effects of luteolin on alleviating METH-induced hepatotoxicity, however, the detailed mechanisms have not been elucidated. In this study, rats were orally pretreated with 100 mg/kg luteolin or sodium dodecyl sulfate water, and then METH (15 mg/kg, intraperitoneal [i.p.]) or saline was administered. Histopathological and biochemical analyses were used to determine the alleviative effects of luteolin. Based on the RNA-sequencing data, METH induced 1859 differentially expressed genes (DEGs) in comparison with the control group, which were enriched into 11 signaling pathways. Among these DEGs, 497 DEGs could be regulated through luteolin treatment and enriched into 16 pathways. The p53 signaling pathway was enriched in both METH administered and luteolin pretreated rats. Meanwhile, luteolin significantly suppressed METH-induced elevation of p53, caspase9, caspase3, cleaved caspase3, the ratio of Bax/Beclin-2, as well as autophagy-related Beclin-1, Atg5, and LC3-II. Luteolin also relieved METH-induced hepatotoxicity by decreasing inflammation factors, including TNF-α, IL-1β, and IL-18. Moreover, the levels of PI3K, p-Akt, and the normalized ratio of p-Akt/Akt declined after METH administration, whereas luteolin pretreatment failed to reverse these effects. Our results suggest that luteolin alleviates METH-induced hepatic apoptosis, autophagy, and inflammation through repressing the p53 pathway. It further illustrates the protective mechanisms of luteolin on METH-induced hepatotoxicity and provides a research basis for clinical treatment.