TY - JOUR

T1 - Detection and quantification of microRNA in cerebral microdialysate

AU - Bache, Søren

AU - Rasmussen, Rune

AU - Rossing, Maria

AU - Hammer, Niels Risør

AU - Juhler, Marianne

AU - Friis-Hansen, Lennart Jan

AU - Cilius Nielsen, Finn

AU - Møller, Kirsten

PY - 2015

Y1 - 2015

N2 - BACKGROUND: Secondary brain injury accounts for a major part of the morbidity and mortality in patients with spontaneous aneurysmal subarachnoid hemorrhage (SAH), but the pathogenesis and pathophysiology remain controversial. MicroRNAs (miRNAs) are important posttranscriptional regulators of complementary mRNA targets and have been implicated in the pathophysiology of other types of acute brain injury. Cerebral microdialysis is a promising tool to investigate these mechanisms. We hypothesized that miRNAs would be present in human cerebral microdialysate.METHODS: RNA was extracted and miRNA profiles were established using high throughput real-time quantification PCR on the following material: 1) Microdialysate sampled in vitro from A) a solution of total RNA extracted from human brain, B) cerebrospinal fluid (CSF) from a neurologically healthy patient, and C) a patient with SAH; and 2) cerebral microdialysate and CSF sampled in vivo from two patients with SAH. MiRNAs were categorized according to their relative recovery (RR) and a pathway analysis was performed for miRNAs exhibiting a high RR in vivo.RESULTS: Seventy-one of the 160 miRNAs detected in CSF were also found in in vivo microdialysate from SAH patients. Furthermore specific miRNAs consistently exhibited either a high or low RR in both in vitro and in vivo microdialysate. Analysis of repeatability showed lower analytical variation in microdialysate than in CSF.CONCLUSIONS: MiRNAs are detectable in cerebral microdialysate; a large group of miRNAs consistently showed a high RR in cerebral microdialysate. Measurement of cerebral interstitial miRNA concentrations may aid in the investigation of secondary brain injury in neurocritical conditions.

AB - BACKGROUND: Secondary brain injury accounts for a major part of the morbidity and mortality in patients with spontaneous aneurysmal subarachnoid hemorrhage (SAH), but the pathogenesis and pathophysiology remain controversial. MicroRNAs (miRNAs) are important posttranscriptional regulators of complementary mRNA targets and have been implicated in the pathophysiology of other types of acute brain injury. Cerebral microdialysis is a promising tool to investigate these mechanisms. We hypothesized that miRNAs would be present in human cerebral microdialysate.METHODS: RNA was extracted and miRNA profiles were established using high throughput real-time quantification PCR on the following material: 1) Microdialysate sampled in vitro from A) a solution of total RNA extracted from human brain, B) cerebrospinal fluid (CSF) from a neurologically healthy patient, and C) a patient with SAH; and 2) cerebral microdialysate and CSF sampled in vivo from two patients with SAH. MiRNAs were categorized according to their relative recovery (RR) and a pathway analysis was performed for miRNAs exhibiting a high RR in vivo.RESULTS: Seventy-one of the 160 miRNAs detected in CSF were also found in in vivo microdialysate from SAH patients. Furthermore specific miRNAs consistently exhibited either a high or low RR in both in vitro and in vivo microdialysate. Analysis of repeatability showed lower analytical variation in microdialysate than in CSF.CONCLUSIONS: MiRNAs are detectable in cerebral microdialysate; a large group of miRNAs consistently showed a high RR in cerebral microdialysate. Measurement of cerebral interstitial miRNA concentrations may aid in the investigation of secondary brain injury in neurocritical conditions.

KW - Brain

KW - Brain Injuries

KW - Cerebrospinal Fluid

KW - Humans

KW - MicroRNAs

KW - Microdialysis

KW - Perfusion

KW - RNA Processing, Post-Transcriptional

KW - Reproducibility of Results

KW - Subarachnoid Hemorrhage

KW - Temperature

KW - Treatment Outcome

U2 - 10.1186/s12967-015-0505-1

DO - 10.1186/s12967-015-0505-1

M3 - Journal article

C2 - 25947950

VL - 13

SP - 1

EP - 10

JO - Journal of Translational Medicine

JF - Journal of Translational Medicine

SN - 1479-5876

IS - 149

M1 - s12967-015-0505-1

ER -