Intracerebral haemorrhage: mechanisms of injury and therapeutic targets

Biomarkers of Functional Outcome in Intracerebral Hemorrhage: Interplay between Clinical Metrics, CD163, and Ferritin

BACKGROUND

Intracerebral hemorrhage (ICH) is associated with neurological decline and poor prognosis. Although many etiologic models have been explored, secondary damage caused by continued inflammation and iron exposure from red blood cell lysis may explain poor outcomes at distant follow-up. Examining serum samples of patients with ICH for biomarkers of iron physiology may yield relationships between iron exposure and functional outcomes.

METHODS

The following study retrospectively evaluated 41 patient serum samples obtained 1 day and 7 days post-ictus for CD163, ferritin, and hepcidin concentrations. Functional outcomes, using the modified Rankin Scale, were dichotomized into good (0-3) and poor (4-6). Correlation analysis and logistic regression were used to explore relationships between biomarker values, clinical metrics (such as ICH Score), and functional outcomes at 3 and 12 months.

RESULTS

Clinical metrics (Acute Physiology and Chronic Health Evaluation II score, ICH Score, and National Institutes of Health Stroke Scale) were correlated with elevated ferritin levels 7 days post-ictus. Furthermore, it was found that mean CD163 levels on day 1 were significantly associated with functional outcomes at 3 and 12 months; mean serum ferritin concentrations on days 1 and 7 were elevated in those with poor outcomes at 3 months, and day 7 levels were independently correlated with 12-month outcomes.

CONCLUSION

Although this study serves to contribute to a growing body of evidence that CD163 and ferritin are biomarkers of functional outcomes, prospective cohort studies may clarify the role of iron-related inflammatory biomarkers as they pertain to neurological decline in patients with ICH.

Up-regulation of Vps4A promotes neuronal apoptosis after intracerebral hemorrhage in adult rats

Vps4, vacuolar protein sorting 4, belongs to ATPases Associated with diverse cellular Activities (AAA) protein family which is made up of Vps4A and Vps4B. Previous studies demonstrated that Vps4A plays vital roles in diverse aspects such as virus budding, the efficient transport of H-Ras to the PM (plasma membrane) and the involvement in the MVB (multivesiculate bodies) pathway. Interestingly, Vps4A is also expressed in the brain. However, the distribution and function of Vps4A in ICH diseases remain unclear. In this study, we show that Vps4A may be involved in neuronal apoptosis during pathophysiological processes of intracerebral hemorrhage (ICH). Based on the results of Western blot and immunohistochemistry, we found a remarkable up-regulation of Vps4A expression surrounding the hematoma after ICH. Double labeled immunofluorescence showed that Vps4A was co-expressed with NeuN but rarely with astrocytes and microglia. Morever, we detected that neuronal apoptosis marker active caspase-3 had co-localizations with Vps4A. Additionaly, Vps4A knockdown in vitro specifically leads to decreasing neuronal apoptosis coupled with increased Akt phosphorylation. All datas suggested that Vps4A was involved in promoting neuronal apoptosis via inhibiting Akt phosphorylation after ICH.

Alternative activation-skewed microglia/macrophages promote hematoma resolution in experimental intracerebral hemorrhage

Microglia/macrophages (MMΦ) are highly plastic phagocytes that can promote both injury and repair in diseased brain through the distinct function of classically activated and alternatively activated subsets. The role of MMΦ polarization in intracerebral hemorrhage (ICH) is unknown. Herein, we comprehensively characterized MMΦ dynamics after ICH in mice and evaluated the relevance of MMΦ polarity to hematoma resolution. MMΦ accumulated within the hematoma territory until at least 14days after ICH induction. Microglia rapidly reacted to the hemorrhagic insult as early as 1-1.5h after ICH and specifically presented a "protective" alternatively activated phenotype. Substantial numbers of activated microglia and newly recruited monocytes also assumed an early alternatively activated phenotype, but the phenotype gradually shifted to a mixed spectrum over time. Ultimately, markers of MMΦ classic activation dominated at the chronic stage of ICH. We enhanced MMΦ alternative activation by administering intraperitoneal injections of rosiglitazone, and subsequently observed elevations in CD206 expression on brain-isolated CD11b⁺ cells and increases in IL-10 levels in serum and perihematomal tissue. Enhancement of MMΦ alternative activation correlated with hematoma volume reduction and improvement in neurologic deficits. Intraventricular injection of alternative activation signature cytokine IL-10 accelerated hematoma resolution, whereas microglial phagocytic ability was abolished by IL-10 receptor neutralization. Our results suggest that MMΦ respond dynamically to brain hemorrhage by exhibiting diverse phenotypic changes at different stages of ICH. Alternative activation-skewed MMΦ aid in hematoma resolution, and IL-10 signaling might contribute to regulation of MMΦ phagocytosis and hematoma clearance in ICH.

The choroid plexus as a site of damage in hemorrhagic and ischemic stroke and its role in responding to injury

While the impact of hemorrhagic and ischemic strokes on the blood–brain barrier has been extensively studied, the impact of these types of stroke on the choroid plexus, site of the blood-CSF barrier, has received much less attention. The purpose of this review is to examine evidence of choroid plexus injury in clinical and preclinical studies of intraventricular hemorrhage, subarachnoid hemorrhage, intracerebral hemorrhage and ischemic stroke. It then discusses evidence that the choroid plexuses are important in the response to brain injury, with potential roles in limiting damage. The overall aim of the review is to highlight deficiencies in our knowledge on the impact of hemorrhagic and ischemic strokes on the choroid plexus, particularly with reference to intraventricular hemorrhage, and to suggest that a greater understanding of the response of the choroid plexus to stroke may open new avenues for brain protection.

Histopathologic Changes of Human Vestibular Epithelia in Intralabyrinthine Hemorrhage

Objective:

To determine whether intralabyrinthine hemorrhage affects vestibular hair cells, dark cells, and transitional cells in human temporal bones.

Methods:

We examined 9 temporal bone specimens from 9 deceased donors with unilateral intralabyrinthine hemorrhage (the hemorrhage group) along with their 9 contralateral temporal bone specimens without hemorrhage (the control group). We estimated the density of type I and type II hair cells in all peripheral sensorial organs (including the cristae of the superior, lateral, and posterior semicircular canals, as well as the maculae of the saccule and utricle). We also estimated the density of dark and transitional cells in the lateral and posterior semicircular canals.

Results:

The loss of type I hair cells in the cristae of the superior, lateral, and posterior semicircular canals and in the maculae of the saccule and utricle was significantly higher in the hemorrhage group, as compared with the control group ( P < .05). The density of type II hair cells in the cristae of the superior and posterior canals and in the macula of the saccule significantly differed between the hemorrhage group and the control group ( P < .05).

Conclusion:

The loss of vestibular hair cells might be the cause of vestibular symptoms in patients with intralabyrinthine hemorrhage.

NLRP3 Inflammasome in Neurological Diseases, from Functions to Therapies

Neuroinflammation has been identified as a causative factor of multiple neurological diseases. The nucleotide-binding oligomerization domain-, leucine-rich repeat- and pyrin domain-containing 3 (NLRP3) inflammasome, a subcellular multiprotein complex that is abundantly expressed in the central nervous system (CNS), can sense and be activated by a wide range of exogenous and endogenous stimuli such as microbes, aggregated and misfolded proteins, and adenosine triphosphate, which results in activation of caspase-1. Activated caspase-1 subsequently leads to the processing of interleukin-1β (IL-1β) and interleukin-18 (IL-18) pro-inflammatory cytokines and mediates rapid cell death. IL-1β and IL-18 drive inflammatory responses through diverse downstream signaling pathways, leading to neuronal damage. Thus, the NLRP3 inflammasome is considered a key contributor to the development of neuroinflammation. In this review article, we briefly discuss the structure and activation the NLRP3 inflammasome and address the involvement of the NLRP3 inflammasome in several neurological disorders, such as brain infection, acute brain injury and neurodegenerative diseases. In addition, we review a series of promising therapeutic approaches that target the NLRP3 inflammasome signaling including anti-IL-1 therapy, small molecule NLRP3 inhibitors and other compounds, however, these approaches are still experimental in neurological diseases. At present, it is plausible to generate cell-specific conditional NLRP3 knockout (KO) mice via the Cre system to investigate the role of the NLRP3 inflammasome, which may be instrumental in the development of novel pharmacologic investigations for neuroinflammation-associated diseases.

Regulatory T cells ameliorate intracerebral hemorrhage-induced inflammatory injury by modulating microglia/macrophage polarization through the IL-10/GSK3β/PTEN axis

Inflammation mediated by the peripheral infiltration of inflammatory cells plays an important role in intracerebral hemorrhage (ICH) induced secondary injury. Previous studies have indicated that regulatory T lymphocytes (Tregs) might reduce ICH-induced inflammation, but the precise mechanisms that contribute to ICH-induced inflammatory injury remain unclear. Our results show that the number of Tregs in the brain increases after ICH. Inducing Tregs deletion using a CD25 antibody or Foxp3^DTR-mice increased neurological deficient scores (NDS), the level of inflammatory factors, hematoma volumes, and neuronal degeneration. Meanwhile, boosting Tregs using a CD28 super-agonist antibody reduced the inflammatory injury. Furthermore, Tregs depletion shifted microglia/macrophage polarization toward the M1 phenotype while boosting Tregs shifted this transition toward the M2 phenotype. In vitro, a transwell co-culture model of microglia and Tregs indicated that Tregs changed the polarization of microglia, decreased the expression of MHC-II, IL-6, and TNF-α and increased CD206 expression. IL-10 originating from Tregs mediated the microglia polarization by increasing the expression of Glycogen Synthase Kinase 3 beta (GSK3β), which phosphorylates and inactivates Phosphatase and Tensin homologue (PTEN) in microglia, TGF-β did not participate in this conversion. Thus, Tregs ameliorated ICH-induced inflammatory injury by modulating microglia/macrophage polarization toward the M2 phenotype through the IL-10/GSK3β/PTEN axis.

Hck Promotes Neuronal Apoptosis Following Intracerebral Hemorrhage

The hematopoietic cell kinase (Hck) is a member of the Src family protein kinases which regulates many signal transduction pathways including cell growth, proliferation, differentiation, migration, and apoptosis. However, the expression and function of Hck after intracerebral hemorrhage (ICH) are unknown. Western blot, immunohistochemistry, and immunofluorescence showed that Hck was obviously up-regulation in neurons adjacent to the hematoma after ICH. In addition, the temporary raise of Hck expression was paralleled with the expression of p53, Bax, and active caspase-3, suggesting that Hck was involved in neuronal apoptosis. Hck siRNA dramatically decrease hemin-induced expression of p53, Bax, and active caspase-3 as well as the amount of apoptotic SH-SY5Y cells in vitro. Furthermore, Hck interacted with p53. Hence, Hck might promote neuronal apoptosis via p53 signaling pathway after ICH.

Neuronal Death After Hemorrhagic Stroke In Vitro and In Vivo Shares Features of Ferroptosis and Necroptosis

BACKGROUND AND PURPOSE

Intracerebral hemorrhage leads to disability or death with few established treatments. Adverse outcomes after intracerebral hemorrhage result from irreversible damage to neurons resulting from primary and secondary injury. Secondary injury has been attributed to hemoglobin and its oxidized product hemin from lysed red blood cells. The aim of this study was to identify the underlying cell death mechanisms attributable to secondary injury by hemoglobin and hemin to broaden treatment options.

METHODS

We investigated cell death mechanisms in cultured neurons exposed to hemoglobin or hemin. Chemical inhibitors implicated in all known cell death pathways were used. Identified cell death mechanisms were confirmed using molecular markers and electron microscopy.

RESULTS

Chemical inhibitors of ferroptosis and necroptosis protected against hemoglobin- and hemin-induced toxicity. By contrast, inhibitors of caspase-dependent apoptosis, protein or mRNA synthesis, autophagy, mitophagy, or parthanatos had no effect. Accordingly, molecular markers of ferroptosis and necroptosis were increased after intracerebral hemorrhage in vitro and in vivo. Electron microscopy showed that hemin induced a necrotic phenotype. Necroptosis and ferroptosis inhibitors each abrogated death by >80% and had similar therapeutic windows in vitro.

CONCLUSIONS

Experimental intracerebral hemorrhage shares features of ferroptotic and necroptotic cell death, but not caspase-dependent apoptosis or autophagy. We propose that ferroptosis or necroptotic signaling induced by lysed blood is sufficient to reach a threshold of death that leads to neuronal necrosis and that inhibition of either of these pathways can bring cells below that threshold to survival.

Sulforaphane Protects against Brain Diseases: Roles of Cytoprotective Enzymes

Sulforaphane (SFN) is a kind of isothiocyanate derived from broccoli and other cruciferous vegetables. Because of its roles of antioxidant, anti-inflammatory, and anti-tumor through multiple targets and various mechanisms, SFN has drawn broad attention of the researchers. One of the most important target of SFN is nuclear factor erythroid 2 related factor 2 (Nrf2), wildly known for its ability to regulate the expression of a series of cytoprotective enzymes with antioxidative, prosurvival, and detoxification effects. Multiple researches have shown that SFN protects against central nervous system diseases through Nrf2pathway. In this article, we list SFN contents in common cruciferous vegetables, and summarize recent advances in the protective effects of SFN against acute brain injuries and neurodegenerative diseases through activating Nrf2 signaling pathway.

Acupuncture for acute moderate thalamic hemorrhage: randomized controlled trial study protocol

Background

Thalamic hemorrhage (TH) is a neurological insult with a high rate of morbidity and mortality. Moderate TH (10–30 ml) accounts for more than half of all TH. Treatment remains controversial. The role of acupuncture in patients with moderate TH is not clear.

Methods

We will conduct a single-center, randomized, parallel group, and assessor-blinded clinical trial. A total of 488 patients with moderate TH will be randomly assigned to one of eight groups: 10–15 cc left sided TH study group (N = 61) and a corresponding control group (N = 61), 10–15 cc right sided TH study group (N = 61) and a corresponding control group, 15–30 cc left sided TH study group (N = 61) and a corresponding control group (N = 61), and 15–30 cc right sided TH study group (N = 61) and a corresponding control group. Study groups will receive acupuncture in addition to standard treatment, while control groups will receive standard treatment alone. The primary outcome will be change in National Institutes of Health Stroke Scale scores at 30 and 90 days after TH. The secondary outcomes will be death or major disability, defined as a score of 3 to 6 on the modified Rankin scale (in which a score of 0 indicates no symptoms, a score of 5 indicates severe disability, and a score of 6 indicates death) at 90-days, need for surgery at 30-days, Glasgow Outcome Scale (GOS) score at 90-days following TH onset, and the results of several additional group specific tests. The rate of adverse events will then be compared between the groups.

Discussion

This study will attempt to answer the question of whether or not acupuncture can improve neurologic outcome following moderate TH.

 Trial registration

Chinese clinical trial registry (ChiCTR-IOR-16008362)

Inflammatory Regulation by Driving Microglial M2 Polarization: Neuroprotective Effects of Cannabinoid Receptor-2 Activation in Intracerebral Hemorrhage

The cannabinoid receptor-2 (CB2R) was initially thought to be the “peripheral cannabinoid receptor.” Recent studies, however, have documented CB2R expression in the brain in both glial and neuronal cells, and increasing evidence suggests an important role for CB2R in the central nervous system inflammatory response. Intracerebral hemorrhage (ICH), which occurs when a diseased cerebral vessel ruptures, accounts for 10–15% of all strokes. Although surgical techniques have significantly advanced in the past two decades, ICH continues to have a high mortality rate. The aim of this study was to investigate the therapeutic effects of CB2R stimulation in acute phase after experimental ICH in rats and its related mechanisms. Data showed that stimulation of CB2R using a selective agonist, JWH133, ameliorated brain edema, brain damage, and neuron death and improved neurobehavioral outcomes in acute phase after ICH. The neuroprotective effects were prevented by SR144528, a selective CB2R inhibitor. Additionally, JWH133 suppressed neuroinflammation and upregulated the expression of microglial M2-associated marker in both gene and protein level. Furthermore, the expression of phosphorylated cAMP-dependent protein kinase (pPKA) and its downstream effector, cAMP-response element binding protein (CREB), were facilitated. Knockdown of CREB significantly inversed the increase of M2 polarization in microglia, indicating that the JWH133-mediated anti-inflammatory effects are closely associated with PKA/CREB signaling pathway. These findings demonstrated that CB2R stimulation significantly protected the brain damage and suppressed neuroinflammation by promoting the acquisition of microglial M2 phenotype in acute stage after ICH. Taken together, this study provided mechanism insight into neuroprotective effects by CB2R stimulation after ICH.

Miconazole protects blood vessels from MMP9-dependent rupture and hemorrhage

Hemorrhagic stroke accounts for 10-15% of all strokes and is strongly associated with mortality and morbidity worldwide, but its prevention and therapeutic interventions remain a major challenge. Here, we report the identification of miconazole as a hemorrhagic suppressor by a small-molecule screen in zebrafish. We found that a hypomorphic mutant fn40a, one of several known β-pix mutant alleles in zebrafish, had the major symptoms of brain hemorrhage, vessel rupture and inflammation as those in hemorrhagic stroke patients. A small-molecule screen with mutant embryos identified the anti-fungal drug miconazole as a potent hemorrhagic suppressor. Miconazole inhibited both brain hemorrhages in zebrafish and mesenteric hemorrhages in rats by decreasing matrix metalloproteinase 9 (MMP9)-dependent vessel rupture. Mechanistically, miconazole downregulated the levels of pErk and Mmp9 to protect vascular integrity in fn40a mutants. Therefore, our findings demonstrate that miconazole protects blood vessels from hemorrhages by downregulating the pERK-MMP9 axis from zebrafish to mammals and shed light on the potential of phenotype-based screens in zebrafish for the discovery of new drug candidates and chemical probes for hemorrhagic stroke.

Summary: A phenotype-based chemical screen in zebrafish identifies miconazole as a novel hemorrhagic suppressor. Miconazole inhibits vessel rupture and hemorrhages by decreasing pErk and MMP9 in zebrafish and rats.

Post-hemorrhagic hydrocephalus: Recent advances and new therapeutic insights

Post-hemorrhagic hydrocephalus (PHH), also referred to as progressive ventricular dilatation, is caused by disturbances in cerebrospinal fluid (CSF) flow or absorption following hemorrhage in the brain. As one of the most serious complications of neonatal/adult intraventricular hemorrhage (IVH), subarachnoid hemorrhage (SAH), and traumatic brain injury (TBI), PHH is associated with increased morbidity and disability of these events. Common sequelae of PHH include neurocognitive impairment, motor dysfunction, and growth impairment. Non-surgical measures to reduce increased intracranial pressure (ICP) in PHH have shown little success and most patients will ultimately require surgical management, such as external ventricular drainage and shunting which mostly by inserting a CSF drainage shunt. Unfortunately, shunt complications are common and the optimum time for intervention is unclear. To date, there remains no comprehensive strategy for PHH management and it becomes imperative that to explore new therapeutic targets and methods for PHH. Over past decades, increasing evidence have indicated that hemorrhage-derived blood and subsequent metabolic products may play a key role in the development of IVH-, SAH- and TBI-associated PHH. Several intervention strategies have recently been evaluated and cross-referenced. In this review, we summarized and discussed the common aspects of hydrocephalus following IVH, SAH and TBI, relevant experimental animal models, clinical translation of in vivo experiments, and potential preventive and therapeutic targets for PHH.

Urokinase, a promising candidate for fibrinolytic therapy for intracerebral hemorrhage

OBJECTIVE Intracerebral hemorrhage (ICH) is associated with a high rate of mortality and severe disability, while fibrinolysis for ICH evacuation is a possible treatment. However, reported adverse effects can counteract the benefits of fibrinolysis and limit the use of tissue-type plasminogen activator (tPA). Identifying appropriate fibrinolytics is still needed. Therefore, the authors here compared the use of urokinase-type plasminogen activator (uPA), an alternate thrombolytic, with that of tPA in a preclinical study. METHODS Intracerebral hemorrhage was induced in adult male Sprague-Dawley rats by injecting autologous blood into the caudate, followed by intraclot fibrinolysis without drainage. Rats were randomized to receive uPA, tPA, or saline within the clot. Hematoma and perihematomal edema, brain water content, Evans blue fluorescence and neurological scores, matrix metalloproteinases (MMPs), MMP mRNA, blood-brain barrier (BBB) tight junction proteins, and nuclear factor-κB (NF-κB) activation were measured to evaluate the effects of these 2 drugs in ICH. RESULTS In comparison with tPA, uPA better ameliorated brain edema and promoted an improved outcome after ICH. In addition, uPA therapy more effectively upregulated BBB tight junction protein expression, which was partly attributed to the different effects of uPA and tPA on the regulation of MMPs and its related mRNA expression following ICH. CONCLUSIONS This study provided evidence supporting the use of uPA for fibrinolytic therapy after ICH. Large animal experiments and clinical trials are required to further explore the efficacy and safety of uPA in ICH fibrinolysis.

Epidemiology, Risk Factors, and Clinical Features of Intracerebral Hemorrhage: An Update

Intracerebral hemorrhage (ICH) is the second most common subtype of stroke and a critical disease usually leading to severe disability or death. ICH is more common in Asians, advanced age, male sex, and low- and middle-income countries. The case fatality rate of ICH is high (40% at 1 month and 54% at 1 year), and only 12% to 39% of survivors can achieve long-term functional independence. Risk factors of ICH are hypertension, current smoking, excessive alcohol consumption, hypocholesterolemia, and drugs. Old age, male sex, Asian ethnicity, chronic kidney disease, cerebral amyloid angiopathy (CAA), and cerebral microbleeds (CMBs) increase the risk of ICH. Clinical presentation varies according to the size and location of hematoma, and intraventricular extension of hemorrhage. Patients with CAA-related ICH frequently have concomitant cognitive impairment. Anticoagulation related ICH is increasing recently as the elderly population who have atrial fibrillation is increasing. As non-vitamin K antagonist oral anticoagulants (NOACs) are currently replacing warfarin, management of NOAC-associated ICH has become an emerging issue.

Endoscopic Evacuation of Basal Ganglia Hematoma: Surgical Technique, Outcome, and Learning Curve

BACKGROUND

Minimally invasive endoscopic hematoma evacuation is a promising treatment option for intracerebral hemorrhage. However, the technique still needs improvement. We report our clinical experience of using this technique to evacuate deep-seated basal ganglia hematomas.

METHODS

The frontal approach was used in most patients. The preoperative and postoperative hematoma volumes, Glasgow Coma Scale, hematoma evacuation rate, 30-day mortality, and long-term outcome defined by the modified Rankin Scale were analyzed retrospectively. The surgical duration per milliliter of clot (DPM) was calculated. The learning curve for this technique was determined based on the relation between the DPM and evacuation rate per the number of cases experienced.

RESULTS

A total of 24 patients were enrolled. The evacuation rate was 87% ± 10%. The average Glasgow Coma Scale score recovered from 8 to 13 after surgery. Twenty-one patients had follow-up data. The follow-up time was 13 ± 6 months. The 30-day mortality after surgery was zero. Forty-eight percent of patients (10/21) achieved a favorable outcome. The DPM (P = 0.92) and evacuation rate (P = 0.64) did not change substantially with the number of cases experienced.

CONCLUSIONS

Endoscopic port surgery for hematoma evacuation via the frontal approach is a safe surgical option for deep-seated basal ganglia hematomas. This technique is minimally invasive and may be helpful to provide better long-term outcomes for selected patients. For neurosurgeons, the learning curve for this technique is steep, which implies that the skills needed for our technique can be easily acquired.

Plasma kallikrein mediates brain hemorrhage and edema caused by tissue plasminogen activator therapy in mice after stroke

Thrombolytic therapy using tissue plasminogen activator (tPA) in acute stroke is associated with increased risks of cerebral hemorrhagic transformation and angioedema. Although plasma kallikrein (PKal) has been implicated in contributing to both hematoma expansion and thrombosis in stroke, its role in the complications associated with the therapeutic use of tPA in stroke is not yet available. We investigated the effects of tPA on plasma prekallikrein (PPK) activation and the role of PKal on cerebral outcomes in a murine thrombotic stroke model treated with tPA. We show that tPA increases PKal activity in vitro in both murine and human plasma, via a factor XII (FXII)-dependent mechanism. Intravenous administration of tPA increased circulating PKal activity in mice. In mice with thrombotic occlusion of the middle cerebral artery, tPA administration increased brain hemorrhage transformation, infarct volume, and edema. These adverse effects of tPA were ameliorated in PPK (Klkb1)-deficient and FXII-deficient mice and in wild-type (WT) mice pretreated with a PKal inhibitor prior to tPA. tPA-induced brain hemisphere reperfusion after photothrombolic middle cerebral artery occlusion was increased in Klkb1^-/- mice compared with WT mice. In addition, PKal inhibition reduced matrix metalloproteinase-9 activity in brain following stroke and tPA therapy. These data demonstrate that tPA activates PPK in plasma and PKal inhibition reduces cerebral complications associated with tPA-mediated thrombolysis in stroke.

Baicalein Promotes Neuronal and Behavioral Recovery After Intracerebral Hemorrhage Via Suppressing Apoptosis, Oxidative Stress and Neuroinflammation

Intracerebral hemorrhage (ICH) is an important public health problem in neurology, which is not only associated with high mortality but also leading to disability. Yet no satisfactory treatment has been developed. The secondary injury that resulted from a number of self-destructive processes such as neuroinflammation, apoptosis and oxidative stress, is the key factor contributing to ICH-induced brain damage. Baicalein has been proved to improve neuronal functional recovery in rat model of subarachnoid hemorrhage and ischemic brain damage. To investigate the effect of baicalein on ICH and its underlying mechanism, a collagenase-induced ICH rat model was performed. Baicalein treatment significantly decreased neurological severity score at day 1 and 3 after ICH injury. Our results showed that the lesion volume, the brain water content, the expression levels of four pro-inflammatory cytokines (IL-1β, IL-4 and IL-6 and TNF-α) and the numbers of apoptotic cells were reduced significantly in ICH rats receiving baicalein treatment, especially in 50 mg/kg baicalein-treated group. Moreover, baicalein increased SOD and GSH-Px activities and down-regulated MDA level of brain tissues in rats. These results suggested that the therapeutic efficacy of baicalein on repairing brain damage is probably caused by suppressing apoptosis, oxidative stress and neuroinflammation. Baicalein could be developed into a novel drug for clinical treatment of ICH and ICH-related brain injuries.

N-methyl-D-aspartic acid receptor 1 (NMDAR1) aggravates secondary inflammatory damage induced by hemin-NLRP3 pathway after intracerebral hemorrhage

OBJECTIVE

Inflammation plays a critical role in secondary brain damage after intracerebral hemorrhage (ICH). However, the mechanisms of inflammatory injury following ICH are still unclear, particularly the involvement of NLRP3 inflammasome, which are crucial to sterile inflammatory responses. In this study, we aim to test the hypothesis that NLRP3 signaling pathway takes a vital position in ICH-induced secondary inflammatory damage and detect the role of N-methyl-D-aspartic acid receptor 1 (NMDAR1) in this progress.

METHODS

ICH was induced in mice by microinjection of hemin into the striatum. The protein levels of NMDAR1, NMDAR1 phosphorylation, NLRP3 and IL-1b were measured by Western blot. The binding of NMDAR1 to NLRP3 was detected by immunoprecipitation.

RESULTS

The expression of NMDAR1, NMDAR1 phosphorylation, NLRP3 and IL-1b were rapidly increased after ICH. Hemin treatment enhanced NMDAR1 expression and NMDAR1 phosphorylation, as well in cultured microglial cells treated by hemin. Hemin up regulated NLRP3 and IL-1b level, which was reversed by MK801 (NMDAR antagonist) in vitro. Hemin also promoted the binding of NMDAR1 to NLRP3.

CONCLUSION

Our findings suggest that NMDAR1 plays a pivotal role in hemin-induced NLRP3-mediated inflammatory damage through synergistic activation.

Transcriptional and Genomic Targets of Neural Stem Cells for Functional Recovery after Hemorrhagic Stroke

Hemorrhagic stroke is a life-threatening disease characterized by a sudden rupture of cerebral blood vessels, and it is widely believed that neural cell death occurs after exposure to blood metabolites or subsequently damaged cells. Neural stem cells (NSCs), which maintain neurogenesis and are found in subgranular zone and subventricular zone, are thought to be an endogenous neuroprotective mechanism for these brain injuries. However, due to the complexity of NSCs and their microenvironment, current strategies cannot satisfactorily enhance functional recovery after hemorrhagic stroke. It is well known that transcriptional and genomic pathways play important roles in ensuring the normal functions of NSCs, including proliferation, migration, differentiation, and neural reconnection. Recently, emerging evidence from the use of new technologies such as next-generation sequencing and transcriptome profiling has provided insight into our understanding of genomic function and regulation of NSCs. In the present article, we summarize and present the current data on the control of NSCs at both the transcriptional and genomic levels. Using bioinformatics methods, we sought to predict novel therapeutic targets of endogenous neurogenesis and exogenous NSC transplantation for functional recovery after hemorrhagic stroke, which could also advance our understanding of its pathophysiology.

Hyperbaric oxygen therapy and preconditioning for ischemic and hemorrhagic stroke

To date, the therapeutic methods for ischemic and hemorrhagic stroke are still limited. The lack of oxygen supply is critical for brain injury following stroke. Hyperbaric oxygen (HBO), an approach through a process in which patients breathe in 100% pure oxygen at over 101 kPa, has been shown to facilitate oxygen delivery and increase oxygen supply. Hence, HBO possesses the potentials to produce beneficial effects on stroke. Actually, accumulated basic and clinical evidences have demonstrated that HBO therapy and preconditioning could induce neuroprotective functions via different mechanisms. Nevertheless, the lack of clinical translational study limits the application of HBO. More translational studies and clinical trials are needed in the future to develop effective HBO protocols.

The Potential Therapeutic Effects of Artesunate on Stroke and Other Central Nervous System Diseases

Artesunate is an important agent for cerebral malaria and all kinds of other severe malaria because it is highly efficient, lowly toxic, and well-tolerated. Loads of research pointed out that it had widespread pharmacological activities such as antiparasites, antitumor, anti-inflammation, antimicrobes activities. As we know, the occurrence and development of neurological disorders usually refer to intricate pathophysiologic mechanisms and multiple etiopathogenesis. Recent progress has also demonstrated that drugs with single mechanism and serious side-effects are not likely the candidates for treatment of the neurological disorders. Therefore, the pluripotent action of artesunate may result in it playing an important role in the prevention and treatment of these neurological disorders. This review provides an overview of primary pharmacological mechanism of artesunate and its potential therapeutic effects on neurological disorders. Meanwhile, we also briefly summarize the primary mechanisms of artemisinin and its derivatives. We hope that, with the evidence presented in this review, the effect of artesunate in prevention and curing for neurological disorders can be further explored and studied in the foreseeable future.

Brain iron overload following intracranial haemorrhage

Intracranial haemorrhages, including intracerebral haemorrhage (ICH), intraventricular haemorrhage (IVH) and subarachnoid haemorrhage (SAH), are leading causes of morbidity and mortality worldwide. In addition, haemorrhage contributes to tissue damage in traumatic brain injury (TBI). To date, efforts to treat the long-term consequences of cerebral haemorrhage have been unsatisfactory. Incident rates and mortality have not showed significant improvement in recent years. In terms of secondary damage following haemorrhage, it is becoming increasingly apparent that blood components are of integral importance, with haemoglobin-derived iron playing a major role. However, the damage caused by iron is complex and varied, and therefore, increased investigation into the mechanisms by which iron causes brain injury is required. As ICH, IVH, SAH and TBI are related, this review will discuss the role of iron in each, so that similarities in injury pathologies can be more easily identified. It summarises important components of normal brain iron homeostasis and analyses the existing evidence on iron-related brain injury mechanisms. It further discusses treatment options of particular promise.

Therapeutic targeting of oxygen-sensing prolyl hydroxylases abrogates ATF4-dependent neuronal death and improves outcomes after brain hemorrhage in several rodent models

Disability or death due to intracerebral hemorrhage (ICH) is attributed to blood lysis, liberation of iron, and consequent oxidative stress. Iron chelators bind to free iron and prevent neuronal death induced by oxidative stress and disability due to ICH, but the mechanisms for this effect remain unclear. We show that the hypoxia-inducible factor prolyl hydroxylase domain (HIF-PHD) family of iron-dependent, oxygen-sensing enzymes are effectors of iron chelation. Molecular reduction of the three HIF-PHD enzyme isoforms in the mouse striatum improved functional recovery after ICH. A low-molecular-weight hydroxyquinoline inhibitor of the HIF-PHD enzymes, adaptaquin, reduced neuronal death and behavioral deficits after ICH in several rodent models without affecting total iron or zinc distribution in the brain. Unexpectedly, protection from oxidative death in vitro or from ICH in vivo by adaptaquin was associated with suppression of activity of the prodeath factor ATF4 rather than activation of an HIF-dependent prosurvival pathway. Together, these findings demonstrate that brain-specific inactivation of the HIF-PHD metalloenzymes with the blood-brain barrier-permeable inhibitor adaptaquin can improve functional outcomes after ICH in several rodent models.

MicroRNA-132 attenuates neurobehavioral and neuropathological changes associated with intracerebral hemorrhage in mice

Recent studies suggest that microRNA-132 (miR-132) potentiates the cholinergic blockade of inflammatory reactions by targeting acetylcholinesterase (AChE) and affords robust protection against ischemia-induced neuronal death. However, the role of miR-132 in intracerebral hemorrhage (ICH) remains unexplored. This study aimed to determine whether miR-132 participates in the process and launches an anti-inflammatory response in a mouse model of ICH. To establish a relationship between miR-132 and ICH-induced neuronal inflammation and death, we used unilateral stereotaxic injections to deliver lentiviruses encoding miR-132, anti-miR-132 or an empty lentiviral vector directly into the right caudate nuclei of 192 living male C57BL/6 mice. Fourteen days later, ICH was induced by injection of autologous blood into these three groups. Neurodeficits, brain edema, blood-brain barrier (BBB) integrity, inflammatory reactions, together with cell death were assessed after ICH. Compared with the control group, the mice overexpressing miR-132 in the brain responded with attenuated neurological deficits and brain edema. The counts of activated microglia and the expression of proinflammatory cytokines were also decreased in these mice. Additionally, BBB integrity improved, and the extent of neuronal death decreased in ICH mice injected with lentivirus encoding miR-132. On the contrary, a decrease of miR-132 expression aggravated the severity of inflammation and increased cell apoptosis. Overall, these findings support a protective role of miR-132 in a mouse model of ICH, providing new opportunities for therapeutic intervention.

Ghrelin Attenuates Intestinal Barrier Dysfunction Following Intracerebral Hemorrhage in Mice

Intestinal barrier dysfunction remains a critical problem in patients with intracerebral hemorrhage (ICH) and is associated with poor prognosis. Ghrelin, a brain-gut peptide, has been shown to exert protection in animal models of gastrointestinal injury. However, the effect of ghrelin on intestinal barrier dysfunction post-ICH and its possible underlying mechanisms are still unknown. This study was designed to investigate whether ghrelin administration attenuates intestinal barrier dysfunction in experimental ICH using an intrastriatal autologous blood infusion mouse model. Our data showed that treatment with ghrelin markedly attenuated intestinal mucosal injury at both histomorphometric and ultrastructural levels post-ICH. Ghrelin reduced ICH-induced intestinal permeability according to fluorescein isothiocyanate conjugated-dextran (FITC-D) and Evans blue extravasation assays. Concomitantly, the intestinal tight junction-related protein markers, Zonula occludens-1 (ZO-1) and claudin-5 were upregulated by ghrelin post-ICH. Additionally, ghrelin reduced intestinal intercellular adhesion molecule-1 (ICAM-1) expression at the mRNA and protein levels following ICH. Furthermore, ghrelin suppressed the translocation of intestinal endotoxin post-ICH. These changes were accompanied by improved survival rates and an attenuation of body weight loss post-ICH. In conclusion, our results suggest that ghrelin reduced intestinal barrier dysfunction, thereby reducing mortality and weight loss, indicating that ghrelin is a potential therapeutic agent in ICH-induced intestinal barrier dysfunction therapy.

Impact of pre-stroke sulphonylurea and metformin use on mortality of intracerebral haemorrhage

Introduction

Few proven therapies for intracerebral haemorrhage exist. Preliminary observational evidence suggests that sulphonylurea and metformin may be protective in ischaemic stroke. We assessed the association of pre-intracerebral haemorrhage sulphonylurea and metformin use on outcome in diabetic patients.

Methods

We merged datasets from the consecutive single-centre Helsinki ICH Study, the intracerebral haemorrhage arm of the Virtual International Stroke Trials Archive (VISTA-ICH) and the Royal Melbourne Hospital ICH Study. Logistic regression adjusting for known predictors of intracerebral haemorrhage outcome (age, sex, baseline Glasgow Coma Scale, National Institutes of Health Stroke Scale, intracerebral haemorrhage volume, infratentorial location, intraventricular extension, and pre-intracerebral haemorrhage warfarin use) estimated the association of metformin and sulphonylurea with all-cause 90-day mortality.

Results

From a dataset of 2404 consecutive intracerebral haemorrhage patients, we included 374 (16%) patients with diabetes. Of these, 113 (30%) died by 90 days. Metformin was used in 148 (40%) patients and sulphonylurea in 115 (31%) patients at intracerebral haemorrhage onset. After adjusting for baseline characteristics, metformin use was associated with lower 90-day mortality (OR 0.51; 95% CI 0.26-0.97; p = 0.041) irrespective of whether the drug was continued or not during the admission, while sulphonylurea use was not associated with mortality (OR 0.96; 95% CI 0.49-1.88; p = 0.906). Haematoma location or evacuation did not modify the association between metformin and mortality; neither did adding insulin use, baseline glucose and serum creatinine into the model (OR 0.50; 95% CI 0.25-0.99; p = 0.047).

Conclusion

Pre-intracerebral haemorrhage metformin use was associated with improved outcome in diabetic intracerebral haemorrhage patients. Our results generate hypotheses which after further validation could be tested in clinical trials.

Intraventricular Transplantation of Autologous Bone Marrow Mesenchymal Stem Cells via Ommaya Reservoir in Persistent Vegetative State Patients after Haemorrhagic Stroke: Report of Two Cases & Review of the Literature

Background: One of the most devastating diseases, stroke, is a leading cause of death and disability worldwide with severe emotional and economic consequences. The purpose of this article is mainly to report the effect of intraventricular transplantation via an Ommaya reservoir using autologous bone marrow mesenchymal stem cells (BM-MSCs) in haemorrhagic stroke patients. Case Presentations: Two patients, aged 51 and 52, bearing sequels of haemorrhagic stroke were managed by intraventricular transplantation of BM-MSCs obtained from their own bone marrow. Before the procedure, both patients were bedridden, tracheostomised, on nasogastric (NG) tube feeding and in hemiparesis. The cells were transplanted intraventricularly (20 x 10⁶ cells/2.5 ml) using an Ommaya reservoir, and then repeated transplantations were done after 1 and 2 months consecutively. The safety and efficacy of the procedures were evaluated 3, 6 and 12 months after treatment. The National Institute of Health Stroke Scale (NIHSS) was used to evaluate the patients' neurological status before and after treatment. No adverse events derived from the procedures or transplants were observed in the one-year follow-up period, and the neurological status of both patients improved after treatment. Conclusions: Our report demonstrates that the intraventricular transplantation of BM-MSCs via an Ommaya reservoir is safe and it improves the neurological status of post-haemorrhagic stroke patients. The repeated transplantation procedure is easier and safer to perform via a subcutaneously implanted Ommaya reservoir. Key Words: Haemorrhagic stroke, bone marrow mesenchymal stem cells (BM-MSCs), intraventricular transplantation.

TGF-β1 modulates microglial phenotype and promotes recovery after intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is a devastating form of stroke that results from the rupture of a blood vessel in the brain, leading to a mass of blood within the brain parenchyma. The injury causes a rapid inflammatory reaction that includes activation of the tissue-resident microglia and recruitment of blood-derived macrophages and other leukocytes. In this work, we investigated the specific responses of microglia following ICH with the aim of identifying pathways that may aid in recovery after brain injury. We used longitudinal transcriptional profiling of microglia in a murine model to determine the phenotype of microglia during the acute and resolution phases of ICH in vivo and found increases in TGF-β1 pathway activation during the resolution phase. We then confirmed that TGF-β1 treatment modulated inflammatory profiles of microglia in vitro. Moreover, TGF-β1 treatment following ICH decreased microglial Il6 gene expression in vivo and improved functional outcomes in the murine model. Finally, we observed that patients with early increases in plasma TGF-β1 concentrations had better outcomes 90 days after ICH, confirming the role of TGF-β1 in functional recovery from ICH. Taken together, our data show that TGF-β1 modulates microglia-mediated neuroinflammation after ICH and promotes functional recovery, suggesting that TGF-β1 may be a therapeutic target for acute brain injury.

Increased expression of HERPUD1 involves in neuronal apoptosis after intracerebral hemorrhage

Homocysteine-inducible endoplasmic reticulum stress-inducible ubiquitin-like domain member 1 protein (HERPUD1) is involved in endoplasmic reticulum stress response. Immense amounts of research showed HERPUD1 plays multiple roles in various models. In this work, we explored the role of HERPUD1 during the pathophysiological processes of intracerebral hemorrhage (ICH). Rat ICH model was established and verified by behavioral test. Western blot and immunohistochemistry revealed a significant up-regulation of HERPUD1 expression around the hematoma after ICH. Besides, the expression of cytochrome c (cyt c) and active caspase-3 increased accompanied to HERPUD1 expression. Double-labeled immunofluorescence indicated HERPUD1 mainly colocalized with neurons. Further study showed HERPUD1 silence brought about up-regulation of apoptosis markers including cyt c and active caspase-3 coupled with increased cell apoptosis in vitro model. All these findings suggested that HERPUD1 might play a protective role in ICH-induced neuronal apoptosis in rat models.

von Willebrand factor contributes to poor outcome in a mouse model of intracerebral haemorrhage

Spontaneous intracerebral haemorrhage (ICH) is the most devastating stroke subtype and has no proven treatment. von Willebrand factor (VWF) has recently been demonstrated to promote inflammation processes. The present study investigated the pathophysiological role of VWF after experimental ICH. Functional outcomes, brain edema, blood-brain barrier (BBB) permeability, cerebral inflammation and levels of intercellular adhesion molecule-1 (ICAM-1) and matrix metalloproteinase-9 (MMP-9) were measured in a mouse model of ICH induced by autologous blood injection. We show that VWF were increased in the plasma and was accumulated in the perihematomal regions of mice subjected to ICH. Injection of VWF resulted in incerased expression of proinflammatory mediators and activation of ICAM-1 and MMP-9, associated with elevated myeloperoxidase, recruitment of neutrophils and microglia. Moreover, mice treated with VWF showed dramatically decreased pericyte coverage, more severe BBB damage and edema formation, and neuronal injury was increased compared with controls. In contrast, blocking antibodies against VWF reduced BBB damage and edema formation and improved neurological function. Together, these data identify a critical role for VWF in cerebral inflammation and BBB damage after ICH. The therapeutic interventions targeting VWF may be a novel strategy to reduce ICH-related injury.

Early Erythrolysis in the Hematoma After Experimental Intracerebral Hemorrhage

Erythrolysis occurs in the clot after intracerebral hemorrhage (ICH), and the release of hemoglobin causes brain injury, but it is unclear when such lysis occurs. The present study examined early erythrolysis in rats. ICH rats had an intracaudate injection of 100 μl autologous blood, and sham rats had a needle insertion. All rats had T2 and T2* magnetic response imaging (MRI) scanning, and brains were used for histology and CD163 (a hemoglobin scavenger receptor) and DARPP-32 (a neuronal marker) immunohistochemistry. There was marked heterogeneity within the hematoma on T2* MRI, with a hyperintense or isointense core and a hypointense periphery. Hematoxylin and eosin staining in the same animals showed significant erythrolysis in the core with the formation of erythrocyte ghosts. The degree of erythrolysis correlated with the severity of perihematomal neuronal loss. Perihematomal CD163 was increased by day 1 after ICH and may be involved in clearing hemoglobin caused by early hemolysis. Furthermore, ICH resulted in more severe erythrolysis, neuronal loss, and perihematomal CD163 upregulation in spontaneously hypertensive rats compared to Wistar-Kyoto rats. In conclusion, T2*MRI-detectable early erythrolysis occurred in the clot after ICH and activated CD163. Hypertension is associated with enhanced erythrolysis in the hematoma.

C1q/Tumor Necrosis Factor-Related Protein-3 Attenuates Brain Injury after Intracerebral Hemorrhage via AMPK-Dependent Pathway in Rat

C1q/tumor necrosis factor (TNF)-related protein-3 (CTRP3) is a recently discovered adiponectin paralog with established metabolic regulatory properties. However, the role of CTRP3 in intracerebral hemorrhage (ICH) is still mostly unresolved. The aim of the present report was to explore the possible neuroprotective effect of CTRP3 in an ICH rat model and to elucidate the fundamental mechanisms. ICH was induced in rats by intracerebral infusion of autologous arterial blood. The effects of exogenous CTRP3 (recombinant or lentivirus CTRP3) on brain injury were explored on day 7. Treatment with CTRP3 reduced brain edema, protected against disruption of the blood-brain barrier (BBB), improved neurological functions and promoted angiogenesis. Furthermore, CTRP3 greatly intensified phosphorylation of AMP-activated protein kinase (AMPK) in addition to expression of hypoxia inducing factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF). Finally, the protective effects of CTRP3 could be blocked by either AMPK or VEGF inhibitors. Our findings give the first evidence that CTRP3 is a new proangiogenic and neuroprotective adipokine, which may exert its protective effects at least partly through an AMPK/HIF-1α/ VEGF-dependent pathway, and suggest that CTRP3 may provide a new therapeutic strategy for ICH.

Signaling pathways involved in HSP32 induction by hyperbaric oxygen in rat spinal neurons

Spinal cord injury (SCI) is a debilitating disease, effective prevention measures are in desperate need. Our previous work found that hyperbaric oxygen (HBO) preconditioning significantly protected rats from SCI after stimulated diving, and in vitro study further testified that HBO protected primary cultured rat spinal neurons from oxidative insult and oxygen glucose deprivation injury via heat shock protein (HSP) 32 induction. In this study, underlying molecular mechanisms were further investigated. The results showed that a single exposure to HBO significantly increased intracellular levels of reactive oxygen species (ROS) and nitric oxide (NO) and activated MEK1/2, ERK1/2, p38 MAPK, CREB, Bach1 and Nrf2. The induction of HSP32 by HBO was significantly reversed by pretreatment neurons with ROS scavenger N-Acetyl-L-cysteine, p38 MAPK inhibitor or Nrf2 gene knockdown, enhanced by MEK1/2 inhibitors or gene knockdown but not by ERK1/2 inhibitor. CREB knockdown did not change the expression of HSP32 induced by HBO. N-Acetyl-L-cysteine significantly inhibited the activation of MEK1/2, ERK1/2, p38 MAPK, and Nrf2. Activation of Nrf2 was significantly inhibited by p38 MAPK inhibitor and the nuclear export of Bach1 was significantly enhanced by MEK1/2 inhibitor. The results demonstrated that HBO induces HSP32 expression through a ROS/p38 MAPK/Nrf2 pathway and the MEK1/2/Bach1 pathway contributes to negative regulation in the process. More importantly, as we know, this is the first study to delineate that ERK1/2 is not the only physiological substrates of MEK1/2.

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HBO induces HSP32 through ROS/p38 MAPK/Nrf2 pathway in rat spinal neurons.

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ROS but not RNS participates in HBO induced HSP32 expression.

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MEK1/2/Bach1 contributes to negative regulation in HBO induced HSP32 expression.

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MEK1/2 acts through pathways other than ERK1/2.

MEKK1 Associated with Neuronal Apoptosis Following Intracerebral Hemorrhage

The JNKs have been implicated in a variety of biological functions in mammalian cells, including apoptosis and the responses to stress. However, the physiological role of these pathways in the intracerebral hemorrhage (ICH) has not been fully elucidated. In this study, we identified a MAPK kinase kinase (MAPKKK), MEKK1, may be involved in neuronal apoptosis in the processes of ICH through the activation of JNKs. From the results of western blot, immunohistochemistry and immunofluorescence, we obtained a significant up-regulation of MEKK1 in neurons adjacent to the hematoma following ICH. Increasing MEKK1 level was found to be accompanied with the up-regulation of p-JNK 3, p53, and c-jun. Besides, MEKK1 co-localized well with p-JNK in neurons, indicating its potential role in neuronal apoptosis. What's more, our in vitro study, using MEKK1 siRNA interference in PC12 cells, further confirmed that MEKK1 might exert its pro-apoptotic function on neuronal apoptosis through extrinsic pathway. Thus, MEKK1 may play a role in promoting the brain damage following ICH.

Electroacupuncture Exerts Neuroprotection through Caveolin-1 Mediated Molecular Pathway in Intracerebral Hemorrhage of Rats

Spontaneous intracerebral hemorrhage (ICH) is one of the most devastating types of stroke. Here, we aim to demonstrate that electroacupuncture on Baihui (GV20) exerts neuroprotection for acute ICH possibly via the caveolin-1/matrix metalloproteinase/blood-brain barrier permeability pathway. The model of ICH was established by using collagenase VII. Rats were randomly divided into three groups: Sham-operation group, Sham electroacupuncture group, and electroacupuncture group. Each group was further divided into 4 subgroups according to the time points of 6 h, 1 d, 3 d, and 7 d after ICH. The methods were used including examination of neurological deficit scores according to Longa's scale, measurement of blood-brain barrier permeability through Evans Blue content, in situ immunofluorescent detection of caveolin-1 in brains, western blot analysis of caveolin-1 in brains, and in situ zymography for measuring matrix metalloproteinase-2/9 activity in brains. Compared with Sham electroacupuncture group, electroacupuncture group has resulted in a significant improvement in neurological deficit scores and in a reduction in Evans Blue content, expression of caveolin-1, and activity of matrix metalloproteinase-2/9 at 6 h, 1 d, 3 d, and 7 d after ICH (P < 0.05). In conclusion, the present results suggested that electroacupuncture on GV20 can improve neurological deficit scores and reduce blood-brain barrier permeability after ICH, and the mechanism possibly targets caveolin-1/matrix metalloproteinase/blood-brain barrier permeability pathway.

CD163 promotes hematoma absorption and improves neurological functions in patients with intracerebral hemorrhage

Clinical outcomes are positively associated with hematoma absorption. The monocyte-macrophage scavenger receptor, CD163, plays an important role in the metabolism of hemoglobin, and a soluble form of CD163 is present in plasma and other tissue fluids; therefore, we speculated that serum CD163 affects hematoma absorption after intracerebral hemorrhage. Patients with intracerebral hemorrhage were divided into high- and low-level groups according to the average CD163 level (1,977.79 ± 832.91 ng/mL). Compared with the high-level group, the low-level group had a significantly slower hematoma absorption rate, and significantly increased National Institutes of Health Stroke Scale scores and modified Rankin Scale scores. These results suggest that CD163 promotes hematoma absorption and the recovery of neurological function in patients with intracerebral hemorrhage.

Review of Preclinical and Clinical Studies of Bone Marrow-Derived Cell Therapies for Intracerebral Hemorrhage

Stroke is the second leading cause of mortality worldwide, causing millions of deaths annually, and is also a major cause of disability-adjusted life years. Hemorrhagic stroke accounts for approximately 10 to 27% of all cases and has a fatality rate of about 50% in the first 30 days, with limited treatment possibilities. In the past two decades, the therapeutic potential of bone marrow-derived cells (particularly mesenchymal stem cells and mononuclear cells) has been intensively investigated in preclinical models of different neurological diseases, including models of intracerebral hemorrhage and subarachnoid hemorrhage. More recently, clinical studies, most of them small, unblinded, and nonrandomized, have suggested that the therapy with bone marrow-derived cells is safe and feasible in patients with ischemic or hemorrhagic stroke. This review discusses the available evidence on the use of bone marrow-derived cells to treat hemorrhagic strokes. Distinctive properties of animal studies are analyzed, including study design, cell dose, administration route, therapeutic time window, and possible mechanisms of action. Furthermore, clinical trials are also reviewed and discussed, with the objective of improving future studies in the field.

Recent Advances of the NLRP3 Inflammasome in Central Nervous System Disorders

Inflammasomes are multiprotein complexes that trigger the activation of caspases-1 and subsequently the maturation of proinflammatory cytokines interleukin-1β and interleukin-18. These cytokines play a critical role in mediating inflammation and innate immunity response. Among various inflammasome complexes, the NLRP3 inflammasome is the best characterized, which has been demonstrated as a crucial role in various diseases. Here, we review recently described mechanisms that are involved in the activation and regulation of NLRP3 inflammasome. In addition, we summarize the recent researches on the role of NLRP3 inflammasome in central nervous system (CNS) diseases, including traumatic brain injury, ischemic stroke and hemorrhagic stroke, brain tumor, neurodegenerative diseases, and other CNS diseases. In conclusion, the NLRP3 inflammasome may be a promising therapeutic target for these CNS diseases.

Effect of integrated traditional Chinese and Western medicine therapy for acute hypertensive intracerebral hemorrhage: a meta-analysis

Intracerebral hemorrhage (ICH) is an important public health problem associated with high mortality and morbidity. The aim of this study was to evaluate the clinical efficacy of integrated traditional Chinese (TCM) and Western medicine (WM) therapy for acute hypertensive ICH. Randomized controlled trials were searched in PubMed, Medline, Embase, Wanfang and CNKI database published between January 2000 and June 2016. Our results showed that integrated TCM and WM therapy appeared to be able to improve the clinical effect for patients with acute hypertensive ICH.

Rate of Perihematomal Edema Expansion Predicts Outcome After Intracerebral Hemorrhage

OBJECTIVES

Intracerebral hemorrhage is a devastating disorder with no current treatment. Whether perihematomal edema is an independent predictor of neurologic outcome is controversial. We sought to determine whether perihematomal edema expansion rate predicts outcome after intracerebral hemorrhage.

DESIGN

Retrospective cohort study.

SETTING

Tertiary medical center.

PATIENTS

One hundred thirty-nine consecutive supratentorial spontaneous intracerebral hemorrhage patients 18 years or older admitted between 2000 and 2013.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Intracerebral hemorrhage, intraventricular hemorrhage, and perihematomal edema volumes were measured from CT scans obtained at presentation, 24-hours, and 72-hours postintracerebral hemorrhage. Perihematomal edema expansion rate was the difference between initial and follow-up perihematomal edema volumes divided by the time interval. Logistic regression was performed to evaluate the relationship between 1) perihematomal edema expansion rate at 24 hours and 90-day mortality and 2) perihematomal edema expansion rate at 24 hours and 90-day modified Rankin Scale score. Perihematomal edema expansion rate between admission and 24-hours postintracerebral hemorrhage was a significant predictor of 90-day mortality (odds ratio, 2.97; 95% CI, 1.48-5.99; p = 0.002). This association persisted after adjusting for all components of the intracerebral hemorrhage score (odds ratio, 2.21; 95% CI, 1.05-4.64; p = 0.04). Similarly, higher 24-hour perihematomal edema expansion rate was associated with poorer modified Rankin Scale score in an ordinal shift analysis (odds ratio, 2.40; 95% CI, 1.37-4.21; p = 0.002). The association persisted after adjustment for all intracerebral hemorrhage score components (odds ratio, 2.07; 95% CI, 1.12-3.83; p = 0.02).

CONCLUSIONS

Faster perihematomal edema expansion rate 24-hours postintracerebral hemorrhage is associated with worse outcome. Perihematomal edema may represent an attractive translational target for secondary injury after intracerebral hemorrhage.