title: Novel microRNA correlations in the severely injured.
abstract: OBJECTIVE
  Severe injury initiates an inflammatory response that can perpetuate immunological dysfunction, uncontrolled inflammation, and subsequent multisystem organ failure. MicroRNAs (miRNAs) have recently been identified as regulators of this inflammatory response. Our study sought to identify the differential expression of unique miRNAs and their correlations with genes of the Toll-like receptor (TLR) pathways, and clinical parameters in the severely injured.
  
  
  METHODS
  Fourteen trauma patients requiring transfusion were prospectively enrolled in this institutional review board-approved study. Inclusion criteria consisted of adult patients deemed clinically to be in hemorrhagic shock necessitating transfusion in the acute phase of their injury care. Peripheral blood samples were obtained after admission to the surgical intensive care unit. Expression of circulating mature miRNA from each patient, as well as from 10 healthy, age-matched controls, was determined and compared using the HiSeq 2500 sequencing system and the R software system. Gene expression of TLR signaling pathways for each patient was examined using custom gene expression polymerase chain reaction arrays. Statistical analyses were performed using general linear models and empirical Bayes methods to determine differential expression and Spearman's nonparametric correlation analysis.
  
  
  RESULTS
  Subjects were 21-77 years old (mean, 42), 80% male, Injury Severity Score 11-43 (mean, 26), with 11 blunt and 3 penetrating injuries. Three were intubated and 5 received blood products before arrival. Base deficit upon hospital admission was 3 to 20 (mean, 9). All patients required blood transfusion secondary to blood loss sustained during injury. Survival to discharge was 93%. Controls were 27-64 years old (mean, 40) and 60% male. Sequencing analysis revealed 69 differentially expressed miRNAs (P < .05) in the severely injured. Within the differentially expressed miRNAs, there were 12 direct and 6 indirect correlations with multiple genes involved in the TLR3 and TLR4 signaling pathways. The relationships between these same miRNAs and clinical parameters were also analyzed. We discovered 4 direct correlations with base deficit and HCO3, and 7 indirect correlations involving total fresh frozen plasma transfused, base deficit, HCO3, and PaCO2 levels.
  
  
  CONCLUSIONS
  Differential expression and correlations between miRNAs, genes of the TLR pathways, and clinical parameters are unique findings in the severely injured and may lead to a greater understanding of the regulation of sterile inflammation after severe injury.
authors.affiliation: Department of Surgery, University of Missouri, Columbia, MO.
authors.forename: Rindi M
authors.initials: RM
authors.lastname: Uhlich
authors.affiliation: Department of Surgery, University of Missouri, Columbia, MO.
authors.forename: Jared A
authors.initials: JA
authors.lastname: Konie
authors.affiliation: Department of Health Management and Informatics, University of Missouri, Columbia, MO.
authors.forename: J Wade
authors.initials: JW
authors.lastname: Davis
authors.affiliation: Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Misfeldt
authors.affiliation: Department of Surgery, University of Missouri, Columbia, MO.
authors.forename: Christopher
authors.initials: C
authors.lastname: Nelson
authors.affiliation: Department of Surgery, University of Missouri, Columbia, MO.
authors.forename: Robert
authors.initials: R
authors.lastname: Calaluce
authors.affiliation: Department of Surgery, University of Missouri, Columbia, MO. Electronic address: barnesste@health.missouri.edu.
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Barnes
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D001803:Blood Transfusion; D016022:Case-Control Studies; D005260:Female; D020869:Gene Expression Profiling; D005819:Genetic Markers; D006801:Humans; D015601:Injury Severity Score; D016014:Linear Models; D008297:Male; D035683:MicroRNAs / Q000097:blood*; D008875:Middle Aged; D010865:Pilot Projects; D011446:Prospective Studies; D017423:Sequence Analysis, RNA; D012771:Shock, Hemorrhagic / Q000097:blood / Q000209:etiology / Q000235:genetics* / Q000628:therapy; D015398:Signal Transduction; D051196:Toll-Like Receptor 3 / Q000378:metabolism*; D051197:Toll-Like Receptor 4 / Q000378:metabolism*; D014947:Wounds and Injuries / Q000097:blood / Q000150:complications / Q000235:genetics* / Q000628:therapy
chemical_list: D015415:Biomarkers; D005819:Genetic Markers; D035683:MicroRNAs; C495344:TLR3 protein, human; C495345:TLR4 protein, human; D051196:Toll-Like Receptor 3; D051197:Toll-Like Receptor 4