David Johnson1, Casandra M Cartagena, Frank C Tortella, Jitendra R Dave, Kara E Schmid, Angela M Boutté. 1. From the Department of Pathology and Area Laboratory Services (D.J.), Landstuhl Regional Medical Center, Landstuhl, Germany; Brain Trauma Neuroprotection and Neurorestoration Branch, Center for Military Psychiatry and Neuroscience (C.M.C., F.C.T., J.R.D., A.M.B.), Walter Reed Army Institute of Research, Silver Spring; and Neurotrauma and Psychological Health Project Management Office (K.E.S.), U.S. Army Medical Materiel Development Activity (USAMMDA), Fort Detrick, Maryland.
Abstract
BACKGROUND: MicroRNAs (miRNAs) are small stable RNAs that regulate translational degradation or repression of genes involved in brain trauma-mediated inflammation. More recently, miRNAs have emerged as potential novel TBI biomarkers. The aim of this study was to determine if a select set of miRNAs (miR-21, Let-7i, miR-124a, miR-146a, miR-107) that were previously associated with TBI models and clinical studies would be dysregulated and correlated to inflammatory cytokine abundance in the rat penetrating ballistic-like brain injury (PBBI) model. METHODS: Adult male Sprague-Dawley rats received a unilateral frontal 10% PBBI, which produces a temporary cavity. Sham animals received a craniotomy only. Ipsilateral brain tissue and serum were collected 4 hours to 7 days post-injury. Quantitation of miR-21, Let-7i, miR-124a, miR-146a, or miR-107 levels was conducted using Taqman PCR assays normalized to the endogenous reference, U6 snRNA. Brain tissue derived from matching cohorts was used to determine 1L-1beta and IL-6 levels by enzyme-linked immunosorbent assay. RESULTS: Brain tissue Let-7i and miR-21 increased at 4 hours and 1 day, whereas miR-124a and miR-107 were enhanced only 1 day post-injury. MiR-146a displayed a biphasic response and increased 1 day and 7 days, whereas elevation of miR-21 was sustained 1 day to 7 days after PBBI. Pathway analysis indicated that miRNAs were linked to inflammatory proteins, IL-6 and IL-1beta. Confirmation by enzyme-linked immunosorbent assay indicated that both cytokines were increased and peaked at 1 day, but fell at 3 days through 7 days after PBBI, indicating an inverse relationship with miRNA abundance. Serum Let-7i, alone, was differentially abundant 7 days after PBBI. CONCLUSION: Brain tissue-derived miRNAs linked to increased cytokine levels demonstrates a plausible therapeutic target of TBI-induced inflammation. Suppression of serum derived Let-7i may have utility as a biomarker of subacute injury progression or therapeutic responses.
BACKGROUND: MicroRNAs (miRNAs) are small stable RNAs that regulate translational degradation or repression of genes involved in brain trauma-mediated inflammation. More recently, miRNAs have emerged as potential novel TBI biomarkers. The aim of this study was to determine if a select set of miRNAs (miR-21, Let-7i, miR-124a, miR-146a, miR-107) that were previously associated with TBI models and clinical studies would be dysregulated and correlated to inflammatory cytokine abundance in the rat penetrating ballistic-like brain injury (PBBI) model. METHODS: Adult male Sprague-Dawley rats received a unilateral frontal 10% PBBI, which produces a temporary cavity. Sham animals received a craniotomy only. Ipsilateral brain tissue and serum were collected 4 hours to 7 days post-injury. Quantitation of miR-21, Let-7i, miR-124a, miR-146a, or miR-107 levels was conducted using Taqman PCR assays normalized to the endogenous reference, U6 snRNA. Brain tissue derived from matching cohorts was used to determine 1L-1beta and IL-6 levels by enzyme-linked immunosorbent assay. RESULTS: Brain tissue Let-7i and miR-21 increased at 4 hours and 1 day, whereas miR-124a and miR-107 were enhanced only 1 day post-injury. MiR-146a displayed a biphasic response and increased 1 day and 7 days, whereas elevation of miR-21 was sustained 1 day to 7 days after PBBI. Pathway analysis indicated that miRNAs were linked to inflammatory proteins, IL-6 and IL-1beta. Confirmation by enzyme-linked immunosorbent assay indicated that both cytokines were increased and peaked at 1 day, but fell at 3 days through 7 days after PBBI, indicating an inverse relationship with miRNA abundance. Serum Let-7i, alone, was differentially abundant 7 days after PBBI. CONCLUSION: Brain tissue-derived miRNAs linked to increased cytokine levels demonstrates a plausible therapeutic target of TBI-induced inflammation. Suppression of serum derived Let-7i may have utility as a biomarker of subacute injury progression or therapeutic responses.
Authors: Martin Cente; Katarina Matyasova; Nikoleta Csicsatkova; Adela Tomikova; Sara Porubska; Yun Niu; Marek Majdan; Peter Filipcik; Igor Jurisica Journal: Cell Mol Neurobiol Date: 2022-07-19 Impact factor: 4.231