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Circular RNA (circRNA), a novel class of noncoding RNAs, has been used extensively to complement transcriptome remodeling in the central nervous system, although the genomic coverage provided has rarely been studied in intracerebral hemorrhage (ICH) and is limited and fails to provide a detailed picture of the cerebral transcriptome landscape. Here, we described sequencing-based transcriptome profiling, providing comprehensive analysis of cerebral circRNA, messenger RNA (mRNA) and microRNA (miRNA) expression in ICH rats. In the study, male Sprague-Dawley rats were subjected to ICH, and next-generation sequencing of RNAs isolated from non-hemorrhagic (Sham) and hemorrhagic (ICH) rat brain samples collected 7 (early phase) and 28 (chronic phase) days after insults, was conducted. Bioinformatics analysis was performed to determine miRNA binding sites and gene ontology of circRNAs, target genes of miRNAs, as well as biological functions of mRNAs, altered after ICH. These analyses revealed different expression profiles of circRNAs, mRNAs and miRNAs in day-7 and day-28 ICH groups, respectively, compared with the Sham. In addition, the expression signature of circRNAs was more sensitive to disease progression than that of mRNAs or miRNAs. Further analysis suggested two temporally specific circRNA-miRNA-mRNA networks based on the competitive endogenous RNA theory, which had profound impacts on brain activities after ICH. In summary, these results suggested an important role for circRNAs in the pathogenesis of ICH and in reverse remodeling based on self-protection support, providing deep insights into diverse possibilities for ICH therapy through targeting circRNAs.

Some neuroprotective agents have been used clinically to address the resulting various adverse effects after intracerebral hemorrhage (ICH). Particularly, effectively removing the hematoma is of practical significance to exert neuroprotective effects following ICH. However, such agents are still in need of development. Lithium chloride (LiCl) has shown neuroprotective effects through glycogen synthase kinase-3β (GSK-3β) inhibition in a variety of central nervous system diseases. However, the impact of LiCl on hematoma clearance and the potential molecular mechanisms have not been reported. We hypothesize that LiCl may exert neuroprotective roles after ICH, partly through promoting hematoma resolution. In this study, male Sprague-Dawley rats were subjected to ICH followed by intraperitoneal injection of LiCl (60 mg/kg). The hematoma volumes of ipsilateral hemisphere were determined using Drabkin's method. The sensorimotor deficits were evaluated by neurobehavioral tests. The expressions of target molecules involved in the process of hematoma clearance were assayed using immunofluorescence and Western blot. Our results showed that animals treated with LiCl presented significantly reduced hematoma volume after ICH, which was coupled with enhanced microglia phagocytosis and its differentiation into M2-phenotype within the first 7 days and up-regulated angiogenesis and neurogenesis in the next 7 days. Meanwhile, GSK-3β was inhibited by LiCl and β-catenin became stabilized, which was followed by up-regulation of nuclear factor erythroid 2-related factor 2 and CD36 from days 3 to 7, and increase of vascular endothelial growth factor and brain-derived neurotrophic factor from days 7 to 14. These data suggest that LiCl promotes hematoma resolution via enhancing microglia phagocytosis and M2-phenotype differentiation in the early stage (< 7 days) and angiogenesis and neurogenesis in the chronic phase (days 7-14), thus eventually improving the functional outcomes of ICH rats., (Copyright © 2019. Published by Elsevier Inc.)

To the clinical cognitive impairment following intracerebral hemorrhage, comprehensive neuropsychological assessments and efficacious interventions have rarely been conducted. Lithium chloride, a classical treatment for bipolar disorder, has shown neuroprotective effects through glycogen synthase kinase-3β inhibition in a variety of central nervous system diseases, including stroke. Since neurons that contain glutamate play crucial roles in psychological functions, such as learning and memory, the glutamate-mediated excitotoxicity and consequent neuronal death and cognitive impairment in hippocampus may co-determine the clinical course of intracerebral hemorrhage. However, the potential molecular mechanisms have rarely been demonstrated in intracerebral hemorrhage researches. In this study, Male Sprague-Dawley rats, subjected to intrastriatal blood infusion, were treated with lithium chloride and underwent neurobehavioral test for equivalent injury severity and neurological functional deficits, Morris water maze test for cognitive impairment, high performance liquid chromatography analysis for excitotoxic index determination, immunohistochemistry analysis for neuronal apoptosis, and Western blot analysis for glycogen synthase kinase-3β activity. Our results showed lithium chloride inhibited glycogen synthase kinase-3β activation, which on one hand, suppressed downstream CRMP-2/NR2B, thus diminishing the excitotoxic index level; and on the other, stabilized β-catenin, thus modulating its downstream apoptosis-related factors such as NF-κB, Bcl-2 and Bax. Meanwhile, glycogen synthase kinase-3β inactivation was paralleled by decreased neuronal death, improved neurological functional deficits and ameliorated cognitive deficits in intracerebral hemorrhage animals. These findings indicate that lithium chloride improves glutamate-mediated excitotoxicity-induced cognitive deficits after intracerebral hemorrhage and that lithium chloride might be a potential therapeutic agent for brain damages caused by intracerebral hemorrhage., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Vasogenic cerebral edema formation after blood-brain barrier (BBB) damage aggravates the devastating consequences of intracerebral hemorrhage (ICH). The present study aims to probe into a therapeutic method on BBB preservation after ICH with a glycogen synthase kinase-3β (GSK-3β) inhibitor, lithium. Intrastriatal infusion of semicoagulated autologous whole blood or sham surgery was performed on male Sprague-Dawley (SD) rats (n = 208). Experimental animals received administration of 4,6-disubstitutedpyrrolo-pyrimidine (TWS119), lithium alone or in combination with a phosphatidylinositol 3-kinase inhibitor, wortmannin, after ICH. Behavioral tests, brain edema, and BBB permeability were determined at 24 and 72 h after surgery. Expressions of Akt, GSK-3β, β-catenin, claudin-1 and claudin-3 were evaluated via Western blots. Our results showed lithium alone posttreatment activated GSK-3β, therefore increasing active β-catenin and claudin-1 and claudin-3 expressions, which were accompanied with improved BBB integrity and ameliorated sensorimotor deficits and brain edema in ICH animals. We concluded that lithium alone reduced BBB damage after ICH, likely through regulating Akt/GSK-3β pathway and stabilizing β-catenin., (Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.)

OBJECTIVE Inflammation and apoptosis are two key factors contributing to secondary brain injury after intracerebral hemorrhage (ICH). The objective of this study was to evaluate the effects of lithium posttreatment on behavior, brain atrophy, inflammation, and perihematomal cell death. Furthermore, the authors aimed to determine the role of the pro-apoptotic glycogen synthase kinase-3β (GSK-3β) after experimental ICH. METHODS Male Sprague-Dawley rats (n = 108) were subjected to intracerebral infusion of semicoagulated autologous blood. Window of opportunity and dose optimization studies of lithium on ICH-induced injury were performed by measuring neurological deficits. Animals with ICH received vehicle administration or lithium posttreatment (60 mg/kg) for up to 21 days. Hemispheric atrophy was evaluated. Perihematomal cell death was quantified through terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL). The number of myeloperoxidase (MPO)-positive neutrophils and OX42-positive microglia in the perihematomal areas were calculated. Western blotting was used for the quantification of GSK-3β, heat shock protein 70 (HSP70), nuclear factor-κB p65 (NF-κB p65), and cy-clooxygenase-2 (COX-2). RESULTS Lithium, at a dose of 60 mg/kg initiated from 2 hours after injury, exhibited the best effects of improving neurological outcomes 3, 5, 7, 14, 21, and 28 days after ICH, reduced the hemispheric atrophy at 42 days after surgery, and reduced the number of TUNEL-positive cells, MPO-positive neutrophils, and OX42-positive microglia in the perihematomal areas. Furthermore, lithium posttreatment modulated GSK-3β, increased HSP70, and decreased NF-κB p65 and COX-2 expression in the ipsilateral hemisphere. CONCLUSIONS Lithium posttreatment at a dose of 60 mg/kg, initiated beginning 2 hours after injury, improves functional and morphological outcomes, and inhibits inflammation and perihematomal cell death in a rat model of semicoagulated autologous blood ICH through inactivation of GSK-3β.

OBJECTIVE In this study, the authors investigated the involvement of 15( S)-hydroxyeicosatetraenoic acid (15(S)-HETE) in the regulation of peroxisome proliferator-activated receptor-γ (PPARγ) after intracerebral hemorrhage (ICH) and its effects on hemorrhage-induced inflammatory response and oxidative stress in an experimental rodent model. METHODS To simulate ICH in a rat model, the authors injected autologous whole blood into the right striatum of male Sprague-Dawley rats. The distribution and expression of 12/15-lipoxygenase (12/15-LOX) were determined by immunohistochemistry and Western blot analysis, respectively. Immunofluorescent double labeling was used to study the cellular localization of 12/15-LOX, and 15(S)-HETE was measured with a 15(S)-HETE enzyme immunoassay kit. Neurological deficits in the animals were assessed through behavioral testing, and apoptotic cell death was determined with terminal deoxynucleotidyl transferase-mediated biotinylated dUTP nick-end labeling. RESULTS Rats with ICH had increased expression of 12/15-LOX predominantly in neurons and also in oligodendrocytes, astrocytes, and microglia. Moreover, ICH elevated production of 15(S)-HETE in the brain area ipsilateral to the blood injection. The PPARγ agonist, exogenous 15(S)-HETE, significantly increased PPARγ protein levels and increased PPARγ-regulated gene (i.e., catalase) expression in the ICH rats. Reduced expression of the gene for the proinflammatory protein nuclear factor κB coincided with decreased neuron damage and improved functional recovery from ICH. A PPARγ antagonist, GW9662, reversed the effects of exogenous 15(S)-HETE on the PPARγ-regulated genes. CONCLUSIONS The induction of 15(S)-HETE during simulated ICH suggests generation of endogenous signals of neuroprotection. The effects of exogenous 15(S)-HETE on brain hemorrhage-induced inflammatory responses and oxidative stress might be mediated via PPARγ.

Objectives: A major limitation of intracerebral haemorrhage (ICH) research is the lack of reproducible animal models. The purpose of the present study was to produce experimental haemorrhages and to characterise the lesion by histology and behaviour in rats., Methods: A total of 180 male SD rats were anaesthetised with chloral hydrate. Rats were placed in a stereotactic frame, and a microinjector was introduced through a burr hole into the right striatum. Each rat received an injection of 60 μL of semi-coagulated autologous whole blood over 6  minutes. The needle was slowly withdrawn 40 minutes after the injection. Control rat had only needle insertion. Time courses of haematoma resolution and pathological changes after intrastriatal injection of semi-coagulated autologous blood were observed. Neurological status was evaluated on days 1, 3, 5, 7, 14 and 21.The behavioural tests used were forelimb placing and a corner turn test., Results: Rats with ICH had a marked, persistent neurological deficit and a highly reproduced haematoma in shape and size. Histologically, haematoma was observed at 1, 3, 5 and 7 days and cysts at 3 weeks. Behavioural abnormalities were present for 14  days, with the recovery of function occurring during the third week., Conclusions: The present ICH model in rats produces a consistent neurological deficit and reproducible haematoma in shape and size. This model could be useful to evaluate the future pharmaceutical therapies in ICH.