Abstract W P210: Plasma Kallikrein Induces Ischemic Brain Damage Through Cleavage-Dependent Activation of NMDA Receptors

Stroke ◽  
2014 ◽  
Vol 45 (suppl_1) ◽  
Author(s):  
Gongxiong wu ◽  
Long-Jun Wu ◽  
David E. Clapham ◽  
Edward P. Feener
Keyword(s):  
Cell Culture ◽  
Cell Death ◽  
Ischemic Stroke ◽  
Nmda Receptor ◽  
Brain Damage ◽  
Infarct Volume ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Plasma Kallikrein ◽  
Ischemic Brain

Background and Purpose: Ischemic stroke ultimately leads to brain dysfunction and neurological deficits. However, the mechanisms that contribute to neuronal injury and dysfunction in ischemic stroke are not fully understood. Recent studies have shown that pharmacological inhibition of the serine protease plasma kallikrein (PK) reduced neuron death and neurological impairment in ischemic brain in mice. In this study, we examine the effects of PK on the neuronal cell death and brain damage in mice and investigate the molecular mechanism of PK-induced neuronal cell death in ischemic stroke. Methods: Ischemia was produced in wild-type (WT) and PK knockout mice by permanent middle cerebral artery occlusion (pMCAO). Infarct volume was quantified by TTC staining and brain function was evaluated by neurological scoring. The effect of PK on neuron cell death in cell culture was determined by lactate dehydrogenase (LDH) release. NMDA receptor function was measured by patch clamp and Ca2+ imaging. NR1 cleavage was detected by western blot. The effect of systemic PK inhibition on pMCAO-induced infarct volume was evaluated in mice treated with the PK inhibitor (BPCCB) or vehicle alone delivered using subcutaneously implanted osmotic pumps. Results: We show that PK deficiency in mice decreased MCAO-induced infarct volume by 39.8% (P<0.01) and improved neurological function compared responses in WT mice. Addition of PK to cell culture media enhanced NMDA-induced cell death of cortical neurons. We further show that PK induced cleavage of NR1 and identify the cleavage site in the extracellular N-terminal domain of NR1. The truncated form of NR1 displayed enhanced NMDA-stimulated current and calcium influx. Treatment of mice with a PK inhibitor reduced MCAO-induced brain damage and neuronal injury. Conclusions: PK enhances NMDA receptor-mediated excitotoxicity and ischemic neuronal death. These findings suggest that PK may serve as a potential therapeutic target for treatment of ischemic stroke.

Abstract 114: Neuroprotective Role of Brain Pericytes through PDGFRβ-Akt Signaling in Ischemic Stroke

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Koichi Arimura ◽  
Tetsuro Ago ◽  
Masahiro Kamouchi ◽  
Hiroshi Sugimori ◽  
Junya Kuroda ◽  
...  
Keyword(s):  
Cell Death ◽  
Ischemic Stroke ◽  
Infarct Volume ◽  
Neurovascular Unit ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Akt Signaling ◽  
Artery Occlusion ◽  
Brain Functions ◽  
Brain Pericytes

Brain pericytes are a constituent of the neurovascular unit and play various important roles in brain functions, such as regulation of capillary blood flow, maintenance of blood-brain barrier and angiogenesis. Previous reports have elucidated that PDGF-B prevents neuronal cell death during ischemic insults in adult rodent models; however, the detailed mechanisms by which PDGF-B signaling protects neurons from ischemic damage are not fully understood. In the present study, we investigated whether brain pericytes play neuroprotective roles in brain ischemia, using a permanent middle cerebral artery occlusion stroke model (MCAO) and cultured human brain pericytes. Immunohistochemistry revealed that the expression of PDGF receptorβ(PDGFRβ) was induced predominantly in pericytes in peri-infarct areas. PDGF-B induced marked phosphorylation of Akt in cultured pericytes. Consistently, Akt was markedly phosphorylated in the PDGFRβ-expressing pericytes in peri-infarct areas. PDGF-B upregulated the expression of neurotrophins, such as neuronal growth factor (NGF) and neurotrophin-3 (NT-3), through Akt activation in the cultured pericytes. We subjected PDGFRβheterozygous knockout (PDGFRβ+/-) mice to MCAO. Infarct volume, as assessed by MAP2 immunostaining, was significantly greater in PDGFRβ+/- than wild-type mice ( 48% increase at day 7, p < 0.01 , n=5). The number of TUNEL positive apoptotic cells was significantly greater in PDGFRβ+/- mice (54 % increase at day 4, p < 0.001 , n=6). Production of NGF and NT-3 at mRNA and protein levels in infarct areas was significantly decreased in PDGFRβ+/- mice (NGF: 28% decrease, p<0.05, NT-3: 22% decrease, p<0.05). Since it has been established that neurotrophin receptors are induced in peri-infarct areas, the decreases in neurotrophin production may increase apoptotic neuronal cell death in the PDGFRβ+/- mice. In conclusion, brain pericytes may have a direct neuroprotective role through secreting neurotrophins via PDGFRβ-Akt signaling, thereby decreasing infarct volume in ischemic stroke.

Cathepsin B and middle cerebral artery occlusion in the rat

1997 ◽  
Vol 87 (5) ◽  
pp. 716-723 ◽  
Author(s):  
Donald Seyfried ◽  
Yuxia Han ◽  
Zhang Zheng ◽  
Nancy Day ◽  
Kamiar Moin ◽  
...  
Keyword(s):  
Cell Death ◽  
Cathepsin B ◽  
Infarct Volume ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Inflammatory Cells ◽  
Ischemic Brain ◽  
Mca Occlusion ◽  
Stefin A ◽  
Intraventricular Infusion

✓ Lysosomal proteases, although tightly regulated under physiological conditions, are known to contribute to cell injury after various forms of tissue ischemia have occurred. Because cathepsin B is a prominent lysosomal protease found in brain parenchyma, the authors hypothesized that it may contribute to neuronal cell death after focal cerebral ischemia. The authors measured the expression and spatial distribution of cathepsin B within the ischemic brain in 43 animals by means of immunohistochemical analysis in a rat model of transient middle cerebral artery (MCA) occlusion. Cathepsin B activity was also measured within specific ischemic brain regions by using an in vitro assay (22 animals). In addition, the authors tested the therapeutic effect of preischemic intraventricular administration of stefin A, a cysteine protease inhibitor, on the volume of cerebral infarction after transient MCA occlusion (15 animals). Increased cathepsin B immunoreactivity was detected exclusively within the ischemic neurons after 2 hours of reperfusion following a 2-hour MCA occlusion. Cathepsin B immunolocalization in the ischemic region decreased by 24 hours of reperfusion, but then increased by 48 hours of reperfusion because the infarct was infiltrated by inflammatory cells. Increased immunolocalization of cathepsin B in the inflammatory cells located in the necrotic infarct core continued through 7 days of reperfusion. Cathepsin B enzymatic activity was significantly increased in the ischemic tissue at 2, 8, and 48 hours, but not at 24 hours of reperfusion after 2 hours of MCA occlusion. Continuous intraventricular infusion of stefin A, before 2 hours of MCA occlusion (15 animals), significantly reduced infarct volume compared with control animals (12 animals): the percentage of hemispheric infarct volume was 20 ± 3.9 compared with 33 ± 3.5 (standard error of the mean; p = 0.025). These data indicate that neuronal cathepsin B undergoes increased expression and activation within 2 hours of reperfusion after a 2-hour MCA occlusion and may be a mechanism contributing to neuronal cell death. Intraventricular infusion of stefin A, an inhibitor of cathepsin B, significantly reduces cerebral infarct volume in rats.

Use of Both Fluoro-Jade B and Hematoxylin and Eosin to Detect Cell Death in the Juvenile Rat Brain Exposed to NMDA-Receptor Antagonists or GABA-Receptor Agonists in Safety Assessment

2021 ◽  
pp. 019262332110077
Author(s):  
Catherine A. Picut ◽  
Odete R. Mendes ◽  
David S. Weil ◽  
Sarah Davis ◽  
Cynthia Swanson
Keyword(s):  
Cell Death ◽  
Nmda Receptor ◽  
Rat Brain ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Nmda Receptor Antagonists ◽  
Neonatal Rats ◽  
Receptor Antagonists ◽  
Fluoro Jade B ◽  
Hematoxylin And Eosin

Administration of pediatric anesthetics with N-methyl D-aspartate (NMDA)-receptor antagonist and/or γ-aminobutyric acid (GABA) agonist activities may result in neuronal degeneration and/or neuronal cell death in neonatal rats. Evaluating pediatric drug candidates for this potential neurotoxicity is often part of overall preclinical new drug development strategy. This specialized assessment may require dosing neonatal rats at postnatal day 7 at the peak of the brain growth spurt and evaluating brain tissue 24 to 48 hours following dosing. The need to identify methods to aid in the accurate and reproducible detection of lesions associated with this type of neurotoxic profile is paramount for meeting the changing needs of neuropathology assessment and addressing emerging challenges in the neuroscience field. We document the use of Fluoro-Jade B (FJB) staining, to be used in conjunction with standard hematoxylin and eosin staining, to detect acute neurodegeneration and neuronal cell death that can be caused by some NMDA-receptor antagonists and/or GABA agonists in the neonatal rat brain. The FJB staining is simple, specific, and sensitive and can be performed on brain specimens from the same cohort of animals utilized for standard neurotoxicity assessment, thus satisfying animal welfare recommendations with no effect on achievement of scientific and regulatory goals.

scholarly journals NMDA Receptor-Mediated Neuroprotective Effect of theScutellaria baicalensisGeorgi Extract on the Excitotoxic Neuronal Cell Death in Primary Rat Cortical Cell Cultures

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Jinsong Yang ◽  
Xiaohong Wu ◽  
Haogang Yu ◽  
Xinbiao Liao ◽  
Lisong Teng
Keyword(s):  
Cell Death ◽  
Nmda Receptor ◽  
Cell Cultures ◽  
Neuroprotective Effect ◽  
Neuronal Cell Death ◽  
Cortical Cell ◽  
Neuronal Cell ◽  
Ethanol Extract ◽  
Phytochemical Analysis ◽  
Cortical Cell Cultures

The objective of the current research work was to evaluate the neuroprotective effect of the ethanol extract ofScutellaria baicalensis(S.B.) on the excitotoxic neuronal cell death in primary rat cortical cell cultures. The inhibitory effects of the extract were qualitatively and quantitatively estimated by phase-contrast microscopy and lactate dehydrogenase (LDH) assays. The extract exhibited a potent and dose-dependent inhibition of the glutamate-induced excitotoxicity in the culture media. Further, using radioligand binding assays, it was observed that the inhibitory effect of the extract was more potent and selective for the N-methyl-D-aspartate (NMDA) receptor-mediated toxicity. The S.B. ethanol extract competed with [3H] MDL 105,519 for the specific binding to the NMDA receptor glycine site with 50% inhibition occurring at 35.1 μg/mL. Further, NMDA receptor inactivation by the S.B. ethanol extract was concluded from the decreasing binding capability of [3H]MK-801 in the presence of the extract. Thus, S.B. extract exhibited neuroprotection against excitotoxic cell death, and this neuroprotection was mediated through the inhibition of NMDA receptor function by interacting with the glycine binding site of the NMDA receptor. Phytochemical analysis of the bioactive extract revealed the presence of six phytochemical constituents including baicalein, baicalin, wogonin, wogonoside, scutellarin, and Oroxylin A.

scholarly journals p53-mediated neuronal cell death in ischemic brain injury

2010 ◽  
Vol 26 (3) ◽  
pp. 232-240 ◽  
Author(s):  
Li-Zhi Hong ◽  
Xiao-Yuan Zhao ◽  
Hui-Ling Zhang
Keyword(s):  
Cell Death ◽  
Brain Injury ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Ischemic Brain Injury ◽  
Ischemic Brain

scholarly journals miR-455 inhibits neuronal cell death by targeting TRAF3 in cerebral ischemic stroke

2016 ◽  
Vol Volume 12 ◽  
pp. 3083-3092 ◽  
Author(s):  
Shengtao Yao ◽  
Bo Tang ◽  
Gang Li ◽  
Ruiming Fan ◽  
Fang Cao
Keyword(s):  
Cell Death ◽  
Ischemic Stroke ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Cerebral Ischemic Stroke ◽  
Cerebral Ischemic

scholarly journals Establishment of an Experimental Intracerebral Haemorrhage Model for Mass Effect Research using a Thermo-sensitive Hydrogel

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Yuhua Gong ◽  
Yuping Gong ◽  
Zongkun Hou ◽  
Tingwang Guo ◽  
Jia Deng ◽  
...  
Keyword(s):  
Cell Death ◽  
Brain Tissue ◽  
Brain Damage ◽  
Intracerebral Haemorrhage ◽  
Brain Oedema ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Mass Effect ◽  
Iron Deposition ◽  
Mass Effects

Abstract The mechanical response of brain tissue closely relates to cerebral blood flow and brain diseases. During intracerebral haemorrhage (ICH), a mass effect occurs during the initial bleeding and results in significant tissue deformation. However, fewer studies have focused on the brain damage mechanisms and treatment approaches associated with mass effects compared to the secondary brain injuries after ICH, which may be a result of the absence of acceptable animal models mimicking a mass effect. Thus, a thermo-sensitive poly (N-isopropylacrylamide) (PNIPAM) hydrogel was synthesized and injected into the rat brain to establish an ICH model for mass effect research. The PNIPAM hydrogel or autologous blood was injected to establish an ICH animal model, and the space-occupying volumes, brain tissue elasticity, brain oedema, neuronal cell death, iron deposition and behavioural recovery were evaluated. The lower critical solution temperature of PNIPAM hydrogel was 32 °C, and the PNIPAM hydrogel had a rough surface with similar topography and pore structure to a blood clot. Furthermore, the ICH model animals who received an injection of PNIPAM and blood produced similar lesion volumes, elasticity changes and mechanically activated ion channel piezo-2 upregulation in brain tissue. Meanwhile, slight iron deposition, neuronal cell death and brain oedema were observed in the PNIPAM hydrogel model compared to the blood model. In addition, the PNIPAM hydrogel showed good biocompatibility and stability in vivo via subcutaneous implantation. Our findings show that PNIPAM hydrogel cerebral infusion can form a mass effect similar to haematoma and minimize the interference of blood, and the establishment of a mass effect ICH model is beneficial for understanding the mechanism of primary brain injury and the role of mass effects in secondary brain damage after ICH.

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