Dataset Information

The Fate of Erythrocytes after Cerebral Hemorrhage.

ABSTRACT: After a cerebral hemorrhage (intracerebral, subarachnoid, and intraventricular), extravasated blood contributes to both initial brain injury, via physical disruption and mass effect, and secondary injury, through the release of potentially neurotoxic and pro-inflammatory factors such as hemoglobin, iron, and peroxiredoxin-2. Erythrocytes are a major blood component and are a source of such damaging factors. Erythrolysis after cerebral hemorrhage releases potential neurotoxins, contributing to brain injury and edema. Alternatively, erythrocyte phagocytosis via microglia or macrophages may limit the spill of neurotoxins therefore limiting subsequent brain injury. The aim of this review is to discuss the process of phagocytosis of erythrocytes by microglia or macrophages after cerebral hemorrhage, the effect of erythrolysis on brain injury, novel mechanisms of erythrocyte and phagocyte egress from the brain, and exciting new targets in this pathway to attenuate brain injury. Understanding the fate of erythrocytes after cerebral hemorrhage may uncover additional potential interventions for clinical translational research.

SUBMITTER: Xia F

PROVIDER: S-EPMC9782724 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The Fate of Erythrocytes after Cerebral Hemorrhage.

Xia Fan F Keep Richard F RF Ye Fenghui F Holste Katherine G KG Wan Shu S Xi Guohua G Hua Ya Y

Translational stroke research 20220123 5

After a cerebral hemorrhage (intracerebral, subarachnoid, and intraventricular), extravasated blood contributes to both initial brain injury, via physical disruption and mass effect, and secondary injury, through the release of potentially neurotoxic and pro-inflammatory factors such as hemoglobin, iron, and peroxiredoxin-2. Erythrocytes are a major blood component and are a source of such damaging factors. Erythrolysis after cerebral hemorrhage releases potential neurotoxins, contributing to br ...[more]

PMID: 35066815

Similar Datasets

Project description:The diagnosis of cerebral vasospasm after Subarachnoid-Hemorrhage is currently very difficult, additional tools such as blood biomarkers are necessary. We tested the ability of gene expression profiles of blood cells to predict vasospasm. 32 patients suffering subarachnoid-hemorrhage were included in this prospective monocentre study. They were grouped according to have a complicated cerebral vasospasm (Vasospasm) or not (Control) and Paired according to age (+/- 10 years), sex, Fisher grade (+/- 1), location, smoking (at least 3 first parameters). Gene expression profiles of blood cells were determined using 25,000~gene microarray. Blood sample: 2.5 mL harvested in PAXgene® Blood RNA tubes (PreAnalytix) RNA extraction: PAXgene® Blood RNA kit (Qiagen). We used a Universel Reference RNA (Stratagene). RNA amplification and labelling: kit Amino Allyl MessageAmp II (Ambion). We hybridized 4 microarrays per patient using pangenomic microarrays from the "Réseau National des Génopôles" (Illkirch, France). 2 slides were hybridized with reference RNA labelled Cy3 and patient RNA labelled Cy5, and 2 slides were hybridized with reference RNA labelled Cy5 and patient RNA labelled Cy3. Hybridation : Agilent protocol with few modifications : 750 ng of each labelled RNA were hubriddized at 60°C during 17 hours in an Aglient hybridization oven. After washings, Slides were scanned with a GenePix 4000B scanner (Molecular Devices). Image intensity data were extracted with GenePix Pro 6.0 analysis software. Quantification of Cy3 and Cy5 and selection of good spots were performed using the MAIA software (Novikov E and Barillot E. Software package for automatic microarray image analysis (MAIA). The ACUITY software was then used to normalize log ratios Cy3/Cy5 with Lowess non linear normalization, to filter out genes not present in at least 3 slides out of 4, to evaluate the reproducibility of the 4 microarrays of each patient (hierarchical clustering, Self Organizing Maps). Statistical analyses to insure reproducibility was performed using Excel (correlation coefficients, ANOVA). Only slides that passed all reprocubility tests were validated.

Project description:To determine the feasibility and acute (i.e., within 72 hrs) safety of three levels of systolic blood pressure reduction in subjects with supratentorial intracerebral hemorrhage treated within 6 hrs after symptom onset.A traditional phase I, dose-escalation, multicenter prospective study.Emergency departments and intensive care units.Patients with intracerebral hemorrhage with elevated systolic blood pressure > or = 170 mm Hg who present to the emergency department within 6 hrs of symptom onset.Intravenous nicardipine to reduce systolic blood pressure to a target of: (1) 170 to 200 mm Hg in the first cohort of patients; (2) 140 to 170 mm Hg in the second cohort; and (3) 110 to 140 mm Hg in the third cohort.Primary outcomes of interest were: (1) treatment feasibility (achieving and maintaining the systolic blood pressure goals for 18-24 hrs); (2) neurologic deterioration within 24 hrs; and (3) serious adverse events within 72 hrs. Safety stopping rules based on neurologic deterioration and serious adverse events were prespecified and approved by an NIH-appointed Data and Safety Monitoring Board, which provided oversight on subject safety. Each subject was followed-up for 3 months to preliminarily assess mortality and the clinical outcomes. A total of 18, 20, and 22 patients were enrolled in the respective three tiers of systolic blood pressure treatment goals. Overall, 9 of 60 patients had treatment failures (all in the last tier). A total of seven subjects with neurologic deterioration were observed: one (6%), two (10%), and four (18%) in tier one, two, and three, respectively. Serious adverse events were observed in one subject (5%) in tier two and in three subjects (14%) in tier three. However, the safety stopping rule was not activated in any of the tiers. Three (17%), two (10%), and five (23%) subjects in tiers one, two, and three, respectively, died within 3 months.The observed proportions of neurologic deterioration and serious adverse events were below the prespecified safety thresholds, and the 3-month mortality rate was lower than expected in all systolic blood pressure tiers. The results form the basis of a larger randomized trial addressing the efficacy of systolic blood pressure reduction in patients with intracerebral hemorrhage.

Project description:BackgroundAneurismal subarachnoid hemorrhage (SAH) is a type of hemorrhagic stroke that, despite improvement through therapeutic interventions, remains a devastating cerebrovascular disorder that has a high mortality rate and causes long-term disability. Cerebral inflammation after SAH is promoted through microglial accumulation and phagocytosis. Furthermore, proinflammatory cytokine release and neuronal cell death play key roles in the development of brain injury. The termination of these inflammation processes and restoration of tissue homeostasis are of utmost importance regarding the possible chronicity of cerebral inflammation and the improvement of the clinical outcome for affected patients post SAH. Thus, we evaluated the inflammatory resolution phase post SAH and considered indications for potential tertiary brain damage in cases of incomplete resolution.MethodsSubarachnoid hemorrhage was induced through endovascular filament perforation in mice. Animals were killed 1, 7 and 14 days and 1, 2 and 3 months after SAH. Brain cryosections were immunolabeled for ionized calcium-binding adaptor molecule-1 to detect microglia/macrophages. Neuronal nuclei and terminal deoxyuridine triphosphate-nick end labeling staining was used to visualize secondary cell death of neurons. The gene expression of various proinflammatory mediators in brain samples was analyzed by quantitative polymerase chain reaction.ResultsWe observed restored tissue homeostasis due to decreased microglial/macrophage accumulation and neuronal cell death 1 month after insult. However, the messenger RNA expression levels of interleukin 6 and tumor necrosis factor α were still elevated at 1 and 2 months post SAH, respectively. The gene expression of interleukin 1β reached its maximum on day 1, whereas at later time points, no significant differences between the groups were detected.ConclusionsBy the herein presented molecular and histological data we provide an important indication for an incomplete resolution of inflammation within the brain parenchyma after SAH. Inflammatory resolution and the return to tissue homeostasis represent an important contribution to the disease's pathology influencing the impact on brain damage and outcome after SAH. Therefore, we consider a novel complementary or even superior therapeutic approach that should be carefully rethought in the management of cerebral inflammation after SAH. An acceleration of the resolution phase at the cellular and molecular levels could be a potential aim in this context.

Dataset Information

The Fate of Erythrocytes after Cerebral Hemorrhage.

Publications

The Fate of Erythrocytes after Cerebral Hemorrhage.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets