Circulating miRNA expression in extracellular vesicles is associated with specific injuries after multiple trauma and surgical invasiveness.

Introduction: Two trauma treatment principles are Early Total Care (ETC), and Damage Control Orthopedics (DCO). Cellular mechanisms that underlie the connection between treatment type, its systemic effects, and tissue regeneration are not fully known. Therefore, this study aimed to: 1) profile microRNA (miRNA) expression in plasma derived Extracellular Vesicles (EVs) from a porcine multiple trauma model at different timepoints, comparing two surgical treatments; and 2) determine and validate the miRNA's messengerRNA (mRNA) targets. Methods: The porcine multiple trauma model consisted of blunt chest trauma, liver laceration, bilateral femur fractures, and controlled haemorrhagic shock. Two treatment groups were defined, ETC (n=8), and DCO (n=8). Animals were monitored under Intensive Care Unit-standards, blood was sampled at 1.5, 2.5, 24, and 72 hours after trauma, and EVs were harvested from plasma. MiRNAs were analysed using quantitative Polymerase Chain Reaction arrays. MRNA targets were identified in silico and validated in vivo in lung and liver tissue. Results: The arrays showed distinct treatment specific miRNA expression patterns throughout all timepoints, and miRNAs related to the multiple trauma and its individual injuries. EV-packed miRNA expression in the ETC group was more pro-inflammatory, indicating potentially decreased tissue regenerative capacities in the acute post-traumatic phase. In silico target prediction revealed several overlapping mRNA targets among the identified miRNAs, related to inflammation, (pulmonary) fibrosis, and Wnt-signalling. These were, among others, A Disintegrin and Metalloproteinase domain-containing protein 10, Collagen Type 1 Alpha 1 Chain, Catenin Beta Interacting Protein 1, and Signal Transducers and Activators of Transcription 3. Validation of these mRNA targets in the lung showed significant, treatment specific deregulations which matched the expression of their upstream miRNAs. No significant mRNA deregulations were observed in the liver. Discussion: This study showed treatment specific, EV-packed miRNA expression patterns after trauma that correlated with mRNA expressions in the lungs, target organs over distance. A systemic response to the increased surgical trauma in the ETC group was identified, with various miRNAs associated with injuries from the trauma model, and involved in (systemic) inflammation, tissue regeneration. EV-transported miRNAs demonstrated a clear role in multiple trauma, warranting further research into tissue-tissue talk and therapeutic applications of EVs after trauma.

Neutrophil Gene Expression Patterns in Multiple Trauma Patients Indicate Distinct Clinical Outcomes.

INTRODUCTION: Patients after polytrauma suffer from posttraumatic immune system dysregulation and multiple organ dysfunction. Genome-wide microarray profiling in monocytes revealed a regulatory network of inflammatory markers around the transcription factor AP-1 in severely injured patients. Recent research focuses on the role of neutrophils in posttraumatic inflammation. The aim of this study was, therefore, to evaluate the impact of this inflammatory network in neutrophils. MATERIALS AND METHODS: Blood sampling and neutrophil separation were performed on admission of the patient and at 6 h, 12 h, 24 h, 48 h, and 72 h after trauma. Neutrophil expression levels of the target genes c-Jun, c-Fos, BCL2A, MMP-9, TIMP-1, ETS-2, IL-1ß, and MIP-1ß were quantified by RT-qPCR. Patients were assorted into groups according to distinct clinical parameters like massive transfusion (>10 RBC units/24 h), injury severity (ISS), 90-d survival, and the presence of traumatic brain injury (defined by ICI on head CT). Statistics were calculated by Mann-Whitney Rank-Sum Test, Receiver Operating Curves, and binary multiple logistic regression. RESULTS: Forty severely injured patients (mean ISS 36 ± 14) were included. BCL2A, MMP-9, TIMP-1, and ETS2 levels showed a significant correlation to 90-d-survival in the early posttraumatic period (6 h-24 h). Furthermore, differential BCL2A, IL-1ß, MIP-1ß, and MMP-9 regulation was observed in patients requiring massive transfusion. We could further show a significant TIMP-1 response in trauma PMN associated with traumatic brain injury. CONCLUSIONS: This study of seriously injured patients highlights very early posttraumatic transcriptional changes in PMNs, which were clearly associated with posttraumatic events and outcomes.

Fracture fixation strategy and specific muscle tissue availability of neutrophilic granulocytes following mono- and polytrauma: intramedullary nailing vs. external fixation of femoral fractures.

BACKGROUND: In the stabilization of femoral fractures in mono- and polytrauma, clinical practice has shown better care through intramedullary nailing. However, the reason why this is the case is not fully understood. In addition to concomitant injuries, the immunological aspect is increasingly coming to the fore. Neutrophil granulocytes (PMNL), in particular next to other immunological cell types, seem to be associated with the fracture healing processes. For this reason, the early phase after fracture (up to 72 h after trauma) near the fracture zone in muscle tissue was investigated in a pig model. MATERIAL AND METHODS: A mono- and polytrauma pig model (sole femur fracture or blunt thoracic trauma, hemorrhagic shock, liver laceration, and femur fracture) was used to demonstrate the immunological situation through muscle biopsies and their analysis by histology and qRT-PCR during a 72 h follow-up phase. Two stabilization methods were used (intramedullary nail vs. external fixator) and compared with a nontraumatized sham group. RESULTS: Monotrauma shows higher PMNL numbers in muscle tissue compared with polytrauma (15.52 ± 5.39 mono vs. 8.23 ± 3.36 poly; p = 0.013), regardless of the treatment strategy. In contrast, polytrauma shows a longer lasting invasion of PMNL (24 h vs. 72 h). At 24 h in the case of monotrauma, the fracture treated with external fixation shows more PMNL than the fracture treated with intramedullary nailing (p = 0.026). This difference cannot be determined in polytrauma probably caused by a generalized immune response. Both monotrauma and polytrauma show a delayed PMNL increase in the muscle tissue of the uninjured side. The use of intramedullary nailing in monotrauma resulted in a significant increase in IL-6 (2 h after trauma) and IL-8 (24 and 48 h after trauma) transcription. CONCLUSION: The reduction of PMNL invasion into the nearby muscle tissue of a monotrauma femur fracture stabilized by intramedullary nailing supports the advantages found in everyday clinical practice and therefore underlines the usage of nailing. For the polytrauma situation, the fixation seems to play a minor role, possibly due to a generalized immune reaction.

miR-142-3p Expression Is Predictive for Severe Traumatic Brain Injury (TBI) in Trauma Patients.

BACKGROUND: Predictive biomarkers in biofluids are the most commonly used diagnostic method, but established markers in trauma diagnostics lack accuracy. This study investigates promising microRNAs (miRNA) released from affected tissue after severe trauma that have predictive values for the effects of the injury. METHODS: A retrospective analysis of prospectively collected data and blood samples of n = 33 trauma patients (ISS ≥ 16) is provided. Levels of miR-9-5p, -124-3p, -142-3p, -219a-5p, -338-3p and -423-3p in severely injured patients (PT) without traumatic brain injury (TBI) or with severe TBI (PT + TBI) and patients with isolated TBI (isTBI) were measured within 6 h after trauma. RESULTS: The highest miR-423-3p expression was detected in patients with severe isTBI, followed by patients with PT + TBI, and lowest levels were found in PT patients without TBI (2-∆∆Ct, p = 0.009). A positive correlation between miR-423-3p level and increasing AIShead (p = 0.001) and risk of mortality (RISC II, p = 0.062) in trauma patients (n = 33) was found. ROC analysis of miR-423-3p levels revealed them as statistically significant to predict the severity of brain injury in trauma patients (p = 0.006). miR-124-3p was only found in patients with severe TBI, miR-338-3p was shown in all trauma groups. miR-9-5p, miR-142-3p and miR-219a-5p could not be detected in any of the four groups. CONCLUSION: miR-423-3p expression is significantly elevated after isolated traumatic brain injury and predictable for severe TBI in the first hours after trauma. miR-423-3p could represent a promising new biomarker to identify severe isolated TBI.

Thirty-eight-negative kinase 1 mediates trauma-induced intestinal injury and multi-organ failure.

Dysregulated intestinal epithelial apoptosis initiates gut injury, alters the intestinal barrier, and can facilitate bacterial translocation leading to a systemic inflammatory response syndrome (SIRS) and/or multi-organ dysfunction syndrome (MODS). A variety of gastrointestinal disorders, including inflammatory bowel disease, have been linked to intestinal apoptosis. Similarly, intestinal hyperpermeability and gut failure occur in critically ill patients, putting the gut at the center of SIRS pathology. Regulation of apoptosis and immune-modulatory functions have been ascribed to Thirty-eight-negative kinase 1 (TNK1), whose activity is regulated merely by expression. We investigated the effect of TNK1 on intestinal integrity and its role in MODS. TNK1 expression induced crypt-specific apoptosis, leading to bacterial translocation, subsequent septic shock, and early death. Mechanistically, TNK1 expression in vivo resulted in STAT3 phosphorylation, nuclear translocation of p65, and release of IL-6 and TNF-α. A TNF-α neutralizing antibody partially blocked development of intestinal damage. Conversely, gut-specific deletion of TNK1 protected the intestinal mucosa from experimental colitis and prevented cytokine release in the gut. Finally, TNK1 was found to be deregulated in the gut in murine and porcine trauma models and human inflammatory bowel disease. Thus, TNK1 might be a target during MODS to prevent damage in several organs, notably the gut.

New Molecular and Epigenetic Expressions as Novel Biomarkers in Critically Ill Polytrauma Patients with Acute Kidney Injury (AKI).

BACKGROUND: A high percentage of the critically ill polytrauma patients develop acute kidney injury (AKI) secondary to trauma and are therefore prone to high morbidity and mortality rates. One of the main objectives in these cases is the fast detection of the condition and continuous rigorous monitoring of the patients. Currently the panel of biomarkers available for monitoring and for the prognosis of AKI is limited. Numerous studies have proven the importance of microRNAs in this field. In this actualization paper we wish to summarize the most relevant microRNAs that can be used as biomarkers for patients with AKI. METHODS: For this paper, we looked into the studies available in scientific databases such as PubMed and Scopus. For the analysis we used the following key words: "miRNAs biomarker", "acute kidney injury AKI", "genetic expression in AKI", and "epigenetic microRNAs biomarkers in AKI". RESULTS: Numerous studies have shown high specificity for certain microRNA species in the case of patients with AKI. Moreover, they have reported a series of microRNAs that present high specificity and that have a strong expression in fluids that can be sampled through non-invasive methods, such as urine and saliva. CONCLUSIONS: The expression of microRNAs can be successfully used in the future as a non-invasive method for the evaluation and monitoring of AKI patients.

Valproic acid induces prosurvival transcriptomic changes in swine subjected to traumatic injury and hemorrhagic shock.

BACKGROUND: Valproic acid (VPA) is a histone deacetylase inhibitor that improves outcomes in large animal models of trauma. However, its protective mechanism of action is not completely understood. We sought to characterize the genetic changes induced by VPA treatment following traumatic injuries. METHODS: Six female Yorkshire swine were subjected to traumatic brain injury (controlled cortical impact), polytrauma (liver and splenic laceration, rib fracture, rectus crush), and hemorrhagic shock (HS, 40% total blood volume). Following 2 hours of HS, animals were randomized to resuscitation with normal saline (NS) or NS + 150 mg/kg of intravenous VPA (n = 3/cohort, 18 samples total). Blood samples were collected for isolation of peripheral blood mononuclear cells at three distinct time points: baseline, 6 hours following injuries, and on postinjury day 1. RNA was extracted from peripheral blood mononuclear cells and sequenced. Differential expression analysis (false discovery rate < 0.001 and p value <0.001) and gene set enrichment (Panther Gene Ontology and Ingenuity Pathway Analysis) was used to compare VPA to non-VPA-treated animals. RESULTS: A total of 628 differentially expressed RNA transcripts were identified, 412 of which were used for analysis. There was no difference between treatment groups at baseline. The VPA-induced genetic changes were similar at 6 hours and on postinjury day 1. Upregulated genes were associated with gene expression (p 2.13E-34), cellular development (1.19E-33), cellular growth and proliferation (1.25E-30), and glucocorticoid receptor signaling (8.6E-21). Downregulated genes were associated with cell cycle checkpoint regulation (3.64E-22), apoptosis signaling (6.54E-21), acute phase response signaling (5.84E-23), and the inflammasome pathway (1.7E-19). CONCLUSION: In injured swine, VPA increases the expression of genes associated with cell survival, proliferation, and differentiation and decreases those associated with cell death and inflammation. These genetic changes could explain the superior clinical outcomes in VPA-treated animals, including smaller brain lesion size and improved neurologic recovery.

Advances in Biomarkers in Critical Ill Polytrauma Patients.

BACKGROUND: The complexity of the cases of critically ill polytrauma patients is given by both the primary, as well as the secondary, post-traumatic injuries. The severe injuries of organ systems, the major biochemical and physiological disequilibrium, and the molecular chaos lead to a high rate of morbidity and mortality in this type of patient. The 'gold goal' in the intensive therapy of such patients resides in the continuous evaluation and monitoring of their clinical status. Moreover, optimizing the therapy based on the expression of certain biomarkers with high specificity and sensitivity is extremely important because of the clinical course of the critically ill polytrauma patient. In this paper we wish to summarize the recent studies of biomarkers useful for the intensive care unit (ICU) physician. METHODS: For this study the available literature on specific databases such as PubMed and Scopus was thoroughly analyzed. Each article was carefully reviewed and useful information for this study extracted. The keywords used to select the relevant articles were "sepsis biomarker", "traumatic brain injury biomarker" "spinal cord injury biomarker", "inflammation biomarker", "microRNAs biomarker", "trauma biomarker", and "critically ill patients". RESULTS: For this study to be carried out 556 original type articles were analyzed, as well as case reports and reviews. For this review, 89 articles with relevant topics for the present paper were selected. The critically ill polytrauma patient, because of the clinical complexity the case presents with, needs a series of evaluations and specific monitoring. Recent studies show a series of either tissue-specific or circulating biomarkers that are useful in the clinical status evaluation of these patients. CONCLUSIONS: The biomarkers existing today, with regard to the critically ill polytrauma patient, can bring a significant contribution to increasing the survival rate, by adapting the therapy according to their expressions. Nevertheless, the necessity remains to research new non-invasive diagnostic methods that present with higher specificity and selectivity.

The Expression of Nuclear Transcription Factor Kappa B (NF-κB) in the Case of Critically Ill Polytrauma Patients with Sepsis and Its Interactions with microRNAs.

Critical polytrauma patients present a series of pathophysiological disturbances, biochemical and molecular dysfunction, which comprise to be the major cause of intensive care unit admission. In regard to molecular damage, there exists a series of factors, which all together contribute to the aggravation of the clinical status leading to increased mortality rate in these patients. One of the most important biochemical factors involved is the nuclear transcription factor B (NF-κB). Impaired NF-κB functioning is reflected on the clinical status of the patient through increased production of pro-inflammatory molecule, leading to multiple organ dysfunction syndrome. In addition to this, through microRNAs interactions, various pathophysiological as well as biochemical disturbances are produced, which altogether further reduce the patient's survival rate. In this paper, we would like to present the modifications seen in the expression of NF-κB in critically polytraumatized patients with sepsis. In additions to this, we would like to discuss the correlation between the microRNAs and its further implications in clinical status of these patients.

Literature Research Regarding miRNAs' Expression in the Assessment and Evaluation of the Critically Ill Polytrauma Patient with Traumatic Brain and Spinal Cord Injury.

BACKGROUND: One of the most severe conditions specific to the critically ill polytrauma patient is traumatic brain injury and traumatic spinal cord injury. The mortality rate is high in the case of these patients, both because of the direct traumatic lesions, and because of the pathophysiological imbalances associated with trauma. Amongst the most common pathologies associated with the critically ill polytrauma patients responsible for a lower survival rate, are redox imbalance, systemic inflammatory response, infections, and multiple organ dysfunction syndrome. METHODS: For this study, was analysed the literature available on PubMed. The key words used in the search were "traumatic brain injury", "spinal cord injury", "microRNAs expression", "polytrauma patients", and "biomarkers". RESULTS: For the study were selected 34 science articles. The oxidative attack on lipids is responsible for the biosynthesis of an increased quantity of free radicals, which further intensifies and aggravates the redox status in these patients. CONCLUSIONS: A new era for biomarkers is represented by the expression of miRNAs. In the case of the critically ill polytrauma patient, using miRNAs' expression as biomarkers for the evaluation and monitoring of the molecular and pathophysiological dysfunctions can bring a range of valuable answers that could contribute to an increased survival rate.

Cell Free DNA and Procalcitonin as Early Markers of Complications in ICU Patients with Multiple Trauma and Major Surgery.

BACKGROUND: Cell free DNA (cfDNA) was recently suggested as a new marker of sepsis and poor outcome in ICU patients. Procalcitonin has also been the focus of attention as an early marker for systemic inflammation and sepsis. METHODS: cfDNA, procalcitonin (PCT), C-reactive protein (CRP), and lactate levels were measured in 30 ICU patients with multiple trauma or after major surgery on the first day of admission and on 5th and 7th days for PCT, CRP, and lactate. cfDNA was measured by real-time PCR, PCT by ELISA, CRP immunoturbidimetrically, and lactate spectrophotometrically. SOFA score and Injury Severity Score (ISS) for trauma patients were calculated. RESULTS: Significantly higher levels of cfDNA were observed in non-survivor patients in comparison to survivors and in patients with sepsis in comparison to those without sepsis (p = 0.002 and p = 0.02, respectively). The ROC curve was calculated for cfDNA as a predictor of outcome, the area under the curve (AUC) was 0.847 (95% CI: 0.669 - 0.952), at a cutoff value of 15500 ng/µL, sensitivity = 83.3%, specificity = 77.8% (p < 0.0001). As a prognostic marker of sepsis, the AUC for cfDNA was 0.788 (95% CI: 0.601 - 0.915), sensitivity = 56.25%, specificity = 100% (p = 0.0007). Day 5 PCT levels significantly correlated with SOFA scores on day 5, ISS on admission (p < 0.001 and p = 0.028, respectively), and a significant elevation of its levels was observed in non-survivor patients compared to survivors (p = 0.001). As a predictor of sepsis, PCT showed a sensitivity of 81.3%, specificity of 100% on day 5, (AUC: 0.987, 95% CI: 0.955 - 1.00); at a cutoff value of 202.90 pg/mL (p = 0.001). As a predictor of outcome, PCT on day 5 showed a sensitivity of 94.0% and a specificity of 78.0% at a cutoff value of 194.40 pg/mL (p = 0.001). Day 1 CRP correlated with ISS on admission, and on day 5 it correlated with SOFA score 5, while lactate correlated with length of stay on days 1, 5, and 7, and its levels were significantly higher in non-survivors on days 5 and 7. CONCLUSIONS: cfDNA is a good predictor of patient outcome in ICU and to a lesser extent as a marker of sepsis. PCT is another promising marker that can complement cfDNA to reach better patient management. Other markers can help in less severe cases.

Epigenetic regulatory pathways involving microRNAs may modulate the host immune response following major trauma.

BACKGROUND: Posttraumatic nosocomial pneumonia is a common complication resulting in significant morbidity. Trauma-induced immunocompromise is associated with an enhanced susceptibility to pneumonia. In this study, we explore the hypothesis that posttranscriptional epigenetic regulation of gene expression may be an important factor in determining this immune phenotype. We describe the pattern of production of microRNAss (miRs) and their association with nosocomial pneumonia following severe trauma. METHODS: A convenience sample of 30 ventilated polytrauma patients ( UKCRN ID: 5637) and 16 healthy controls were recruited. Messenger RNA and protein levels of key cytokines were quantified within 2 hours of the injury and at 24 hours. Three miRs per cytokine were then selected based on miRBase target prediction scores and quantified using polymerase chain reaction. Nosocomial pneumonia was defined using the Centers for Disease Control and Prevention definitions. RESULTS: Median Injury Severity Score (ISS) was 29, and 47% of the patients developed nosocomial pneumonia. miR-125a and miR-202 decreased by 34% and 77%, respectively, immediately following injury, whereas their target, IL-10, increased messenger RNA levels 3-fold and protein levels 180-fold. Tumor necrosis factor α (TNF-α) and IL-12 gene expression decreased by 68% and 43%, respectively, following injury, and this was mirrored by a 10-fold increase in miR-181, an miR predicted to target TNF-α transcripts. Lower levels of miR-125a and miR-374b were associated with the later acquisition of hospital-acquired pneumonia. CONCLUSION: Alteration in the expression of miRs with highly predicted complementarity to IL-10 and TNF-α may be an important mechanism regulating the posttraumatic immunosuppressive phenotype in intensive care unit patients. LEVEL OF EVIDENCE: Retrospective observational study, level III.

Genetic variants of microRNA sequences and susceptibility to sepsis in patients with major blunt trauma.

OBJECTIVE: The objective of this study was to conduct a systematic survey of common precursor microRNA (pre-miRNA) single nucleotide polymorphisms (SNPs) and evaluate their clinical relevance in patients with major blunt trauma. BACKGROUND: Recent evidence indicates that small noncoding RNA molecules known as miRNAs can function as important negative gene regulators and are implicated in the pathogenesis of various diseases. METHODS: We conducted a 2-stage study to examine the impact of 9 selected SNPs with potential functional significance on the susceptibility to sepsis of 1268 trauma patients (1 screening cohort, n = 666) and 2 independent validated cohorts (n = 286 and n = 316, respectively) in China. RESULTS: Among the 9 selected SNPs with potential functional significance, only 1 (miR-608 rs4919510) was found to be strongly associated with a higher risk of developing sepsis and multiple organ dysfunction in all 3 independent study cohorts. An even stronger association was observed for the rs4919510 polymorphism when combining these 3 study cohorts together. In addition, the rs4919510 polymorphism showed a significant correlation with a higher production of proinflammatory cytokines and a lower production of anti-inflammatory cytokines. In vitro experiments further indicated that the G→C variant of this polymorphism could significantly increase the expression of mature miR-608. CONCLUSIONS: Our results indicate that the rs4919510G/C SNP in hsa-mir-608 may be a prognostic biomarker for sepsis in patients with major trauma. Further characterization of miRNA SNPs may open new avenues for studying sepsis and developing novel therapeutic approaches.

An obligatory role of NF-κB in mediating bone marrow derived endothelial progenitor cell recruitment and proliferation following endotoxemic multiple organ injury in mice.

BACKGROUND: Recruitment of bone marrow derived endothelial progenitor cells (BMDEPCs) alleviates multiple organ injury (MOI) and improves outcomes. However, mechanisms mediating BMDEPC recruitment following septic MOI remain largely unknown. This study characterized the kinetics of BMDEPC recruitment and proliferation and defined the role of NF-κB in regulating BMDEPC recruitment and proliferation. METHODS AND MAIN FINDINGS: Chimeric mice with an intact or disrupted NF-κB p50 gene and BMDEPC-restricted expression of green fluorescent protein were created and injected with LPS (2 mg/kg, i.p.). BMDEPC recruitment and proliferation in multiple organs were quantified. BMDEPC recruitment and proliferation are highly organ-dependent. Lungs had the highest number of BMDEPC recruitment, whereas heart, liver and kidney had only a small fraction of the number of BMDEPCs in lungs. Number of proliferating BMDEPCs was several-fold higher in lungs than in other 3 organs. Kinetically, BMDEPC recruitment into different organs showed different time course profiles. NF-κB plays obligatory roles in mediating BMDEPC recruitment and proliferation. Universal deletion of NF-κB p50 gene inhibited LPS-induced BMDEPC recruitment and proliferation by 95% and 69% in heart. However, the contribution of NF-κB to these regulations varies significantly between organs. In liver, universal p50 gene deletion reduced LPS-induced BMDEPC recruitment and proliferation only by 49% and 35%. NF-κB activities in different tissue compartments play distinct roles. Selective p50 gene deletion either in stromal/parenchymal cells or in BM/blood cells inhibited BMDEPC recruitment by a similar extent. However, selective p50 gene deletion in BM/blood cells inhibited, but in stromal/parenchymal cells augmented BMDEPC proliferation. CONCLUSIONS: BMDEPC recruitment and proliferation display different kinetics in different organs following endotoxemic MOI. NF-κB plays obligatory and organ-dependent roles in regulating BMDEPC recruitment and proliferation. NF-κB activities in different tissue compartments play distinct roles in regulating BMDEPC proliferation.

Fed state prior to hemorrhagic shock and polytrauma in a porcine model results in altered liver transcriptomic response.

Hemorrhagic shock is a leading cause of trauma-related mortality in both civilian and military settings. Resuscitation often results in reperfusion injury and survivors are susceptible to developing multiple organ failure (MOF). The impact of fed state on the overall response to shock and resuscitation has been explored in some murine models but few clinically relevant large animal models. We have previously used metabolomics to establish that the fed state results in a different metabolic response in the porcine liver following hemorrhagic shock and resuscitation. In this study, we used our clinically relevant model of hemorrhagic shock and polytrauma and the Illumina HiSeq platform to determine if the liver transcriptomic response is also altered with respect to fed state. Functional analysis of the response to shock and resuscitation confirmed several typical responses including carbohydrate metabolism, cytokine inflammation, decreased cholesterol synthesis, and apoptosis. Our findings also suggest that the fasting state, relative to a carbohydrate prefed state, displays decreased carbohydrate metabolism, increased cytoskeleton reorganization and decreased inflammation in response to hemorrhagic shock and reperfusion. Evidence suggests that this is a consequence of a shrunken, catabolic state of the liver cells which provides an anti-inflammatory condition that partially mitigates hepatocellar damage.

Clinical relevance of IL-6 gene polymorphism in severely injured patients.

In polytrauma, injuries that may be surgically treated under regular circumstances due to a systemic inflammatory response become life-threatening. The inflammatory response involves a complex pattern of humoral and cellular responses and the expression of related factors is thought to be governed by genetic variations. This aim of this paper is to examine the influence of interleukin (IL) 6 single nucleotide polymorphism (SNP) -174C/G and -596G/A on the treatment outcome in severely injured patients. Forty-seven severely injured patients were included in this study. Patients were assigned an Injury Severity Score. Blood samples were drawn within 24 h after admission (designated day 1) and on subsequent days (24, 48, 72 hours and 7 days) of hospitalization. The IL-6 levels were determined through ELISA technique. Polymorphisms were analyzed by a method of Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR). Among subjects with different outcomes, no statistically relevant difference was found with regards to the gene IL-6 SNP-174G/C polymorphism. More than a half of subjects who died had the SNP-174G/C polymorphism, while this polymorphism was represented in a slightly lower number in survivors. The incidence of subjects without polymorphism and those with heterozygous and homozygous gene IL-6 SNP-596G/A polymorphism did not present statistically significant variations between survivors and those who died. The levels of IL-6 over the observation period did not present any statistically relevant difference among subjects without the IL-6 SNP-174 or IL- 6 SNP -596 gene polymorphism and those who had either a heterozygous or a homozygous polymorphism.

Screening of differentially expressed genes between multiple trauma patients with and without sepsis.

The purpose of this study was to identify critical genes associated with septic multiple trauma by comparing peripheral whole blood samples from multiple trauma patients with and without sepsis. A microarray data set was downloaded from the Gene Expression Omnibus (GEO) database. This data set included 70 samples, 36 from multiple trauma patients with sepsis and 34 from multiple trauma patients without sepsis (as a control set). The data were preprocessed, and differentially expressed genes (DEGs) were then screened for using packages of the R language. Functional analysis of DEGs was performed with DAVID. Interaction networks were then established for the most up- and down-regulated genes using HitPredict. Pathway-enrichment analysis was conducted for genes in the networks using WebGestalt. Fifty-eight DEGs were identified. The expression levels of PLAU (down-regulated) and MMP8 (up-regulated) presented the largest fold-changes, and interaction networks were established for these genes. Further analysis revealed that PLAT (plasminogen activator, tissue) and SERPINF2 (serpin peptidase inhibitor, clade F, member 2), which interact with PLAU, play important roles in the pathway of the component and coagulation cascade. We hypothesize that PLAU is a major regulator of the component and coagulation cascade, and down-regulation of PLAU results in dysfunction of the pathway, causing sepsis.

Screening of differentially expressed genes related to severe sepsis induced by multiple trauma with DNA microarray.

OBJECTIVES: Severe sepsis after trauma still associated with a high mortality rate in intensive care units (ICU). In this study we aimed to identify genes related to multiple trauma complicated by severe sepsis. MATERIALS AND METHODS: The gene expression profile dataset GSE12624 including 36 samples of traumatic patients not complicated by sepsis and 34 traumatic patients complicated by sepsis was downloaded from GEO (Gene Expression Omnibus) database. The limma package in R was applied to identify differentially expressed genes (DEGs) between these two groups of samples. All the DEGs were divided into up- and down-regulation groups according to the changes of their expression value, which were then subjected to GO enrichment analysis. Two genes with largest changes among the up- and down-regulation groups were selected. Interaction networks based on these two genes were constructed using HitPredict software and then pathway enrichment analysis for the networks were performed by WebGestalt software. RESULTS: A total of 21 up-regulated genes and 37 down-regulated genes were obtained, which were mainly related to GO terms "endopeptidase inhibitor activity" and "response to wounding", respectively. The |logFC| of genes PLAU (urokinase-type plasminogen activator) and MMP8 (matrix metalloproteinase-8) ranked first in down-regulated or up-regulated list. There were 18 genes which can interact with PLAU at a high degree of confidence while there were 5 genes with MMP8. Further analysis showed that PLAU was closely associated with the pathway "complement and coagulation cascades". CONCLUSIONS: PLAU and MMP8 may act as potential targets for diagnosis and therapy of trauma complicated by sepsis.

Identification of haplotype tag single nucleotide polymorphisms within the receptor for advanced glycation end products gene and their clinical relevance in patients with major trauma.

INTRODUCTION: The receptor for advanced glycation end products (RAGE) has been considered as one of the major pattern recognition receptors and plays an important role in the development of sepsis and multiple organ dysfunction in critical illnesses. Although genetic variants of the RAGE gene have been shown to be well associated with susceptibility to some inflammatory diseases, little is known about their clinical relevance in the development of sepsis in critical ill patients. METHODS: Four genetic variants were selected from the entire RAGE gene and genotyped using pyrosequencing and polymerase chain reaction-length polymorphism methods. Association studies were performed in two independent Chinese Han populations. RESULTS: Among the four genetic variants, only the rs1800625 polymorphism was significantly associated with sepsis morbidity rate and multiple organ dysfunction (MOD) scores in patients with major trauma both in Chongqing (n = 496) and Zhejiang (n = 232) districts, respectively. Results from ex vivo responsiveness of peripheral blood leukocytes indicated that the rs1800625 polymorphism was well associated with decreased production of TNFα. In addition, the rs1800625 polymorphism could significantly inhibit the promoter activities of the RAGE gene. CONCLUSIONS: The rs1800625 polymorphism is a functional variant, which might be used as a relevant risk estimate for the development of sepsis and multiple organ dysfunction syndrome in patients with major trauma.

Blood group genotyping in a multitrauma patient: a case report.

Currently DNA-based analysis of blood groups is mainly used to improve transfusion safety by reducing alloantibody formation in multiply transfused patients and by monitoring pregnancies at risk for hemolytic disease of the fetus and newborn. We present a case in which genotyping was performed after massive transfusion with unmatched group O, D- blood in a trauma setting. Our patient was genotyped as O1A1 and predicted to be D-, and we therefore transfused group A, D- red blood cell concentrates. This case demonstrates how the use of blood group genotyping in an acute setting can lead to a decrease in the unnecessary use of group O, D- blood products.