Abstract TP77: New treatment

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Munehisa Shimamura ◽  
Hironori Nakagami ◽  
Kouji Wakayama ◽  
Tomohiro Kawano ◽  
Hideki Mochizuki ◽  
...  
Keyword(s):  
Infarct Volume ◽  
Artery Occlusion ◽  
Therapeutic Effects ◽  
Systemic Injection ◽  
Ischemic Brain ◽  
Trap Staining ◽  
Osteoclast Activation ◽  
New Treatment ◽  
Cerebral Artery Occlusion ◽  
Radial Bone

Background and purpose: We previously showed that stimulation of RANKL (receptor activator of nuclear factor-B ligand)/ RANK (receptor for RANKL) signal with novel RANKL-based partial peptide, MHP1, worked as anti-inflammatory in microglia and macrophages without induction of osteoclast activation, but the effects of systemic injection of MHP1 in ischemic brain is still unclear. Here, we examined the effects of systemically injected MHP1 in ischemic brain. Methods: FITC-conjugated MHP1 was injected via jugular vein 4 hrs after transient middle cerebral artery occlusion (tMCAo) in C57BL6J mice to check whether MHP1 could penetrate into infarct parenchyma. To examine whether MHP1 has therapeutic effects, MHP1 was injected intravenously (IV) followed by successive subcutaneous injection with Alzet pump beginning at 4 or 6 hrs after tMCAo. The effects of MHP1 for osteoclast activation in the radial bone in paralyzed upper arm were examined by TRAP staining. Results: Immunohistochemistry for FITC showed that MHP1 could successfully penetrated into infarct parenchyma 5 min after IV injection of MHP1, but the penetrated MHP1 was not observed 1 hr after injection. These results indicated that MHP1 should be administered continuously to achieve successive penetration into infarct parenchyma. The mice treated with MHP1 showed less neurological severity score and infarct volume at 48 hrs after tMCAo even when the treatment was started at 6 hrs after MCAo. TRAP staining showed that osteoclast activation in paralyzed radial bone was inhibited in MHP1-treated mice, suggesting that MHP1 could prevent osteoclast activation as well as ischemic injury. Conclusion: Systemically injected MHP1 could successfully penetrated into infarct parenchyma and prevent exacerbation of paralysis and infarct size after tMCAo. Although further studies for improvement of its stability are needed, MHP1 might be a novel agent to treat ischemic brain.

scholarly journals Impact of Age and Sex on α-Syn (α-Synuclein) Knockdown-Mediated Poststroke Recovery

Stroke ◽  
2020 ◽  
Vol 51 (10) ◽  
pp. 3138-3141
Author(s):  
Bharath Chelluboina ◽  
Taehee Kim ◽  
Suresh L. Mehta ◽  
Joo-Yong Kim ◽  
Saivenkateshkomal Bathula ◽  
...  
Keyword(s):  
Brain Damage ◽  
Infarct Volume ◽  
Critical Role ◽  
Artery Occlusion ◽  
Motor Deficits ◽  
Ischemic Brain ◽  
Therapeutic Opportunity ◽  
Interfering Rna ◽  
Cerebral Artery Occlusion ◽  
Age And Sex

Background and Purpose: Increased expression of α-Syn (α-Synuclein) is known to mediate secondary brain damage after stroke. We presently studied if α-Syn knockdown can protect ischemic brain irrespective of sex and age. Methods: Adult and aged male and female mice were subjected to transient middle cerebral artery occlusion. α-Syn small interfering RNA (siRNA) was administered intravenous at 30 minutes or 3 hour reperfusion. Poststroke motor deficits were evaluated between day 1 and 7 and infarct volume was measured at day 7 of reperfusion. Results: α-Syn knockdown significantly decreased poststroke brain damage and improved poststroke motor function recovery in adult and aged mice of both sexes. However, the window of therapeutic opportunity for α-Syn siRNA is very limited. Conclusions: α-Syn plays a critical role in ischemic brain damage and preventing α-Syn protein expression early after stroke minimizes poststroke brain damage leading to better functional outcomes irrespective of age and sex.

scholarly journals Reduction of Infarct Volume by Magnesium after Middle Cerebral Artery Occlusion in Rats

1991 ◽  
Vol 11 (6) ◽  
pp. 1025-1030 ◽  
Author(s):  
Yoshio Izumi ◽  
Simon Roussel ◽  
Elisabeth Pinard ◽  
Jacques Seylaz
Keyword(s):  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Focal Cerebral Ischemia ◽  
Infarct Volume ◽  
Artery Occlusion ◽  
Triphenyltetrazolium Chloride ◽  
Ischemic Brain ◽  
Mca Occlusion ◽  
Cerebral Artery Occlusion ◽  
Hyperglycemic Effect

The effects of magnesium, an endogenous inhibitor of calcium entry into neurons, upon ischemic brain damage were investigated using a well-characterized model of focal cerebral ischemia in rats. Infarct volumes were determined by 2,3,5-triphenyltetrazolium chloride transcardiac perfusion 48 h after middle cerebral artery (MCA) occlusion. The area of ischemic damage was quantified by image analysis in coronal sections taken every 0.5 mm. MgCl2 (1 mmol/kg) was injected intraperitoneally just after MCA occlusion and again 1 h later. Posttreatment with MgCl2 (16 control and 16 treated rats) significantly reduced the cortical infarct volume. Compensation for the hyperglycemic effect of MgCl2 with insulin (17 rats) further reduced the infarct volume in the neocortex. No systemic effects of either treatment could account for the observed neuroprotection.

Abstract W MP81: Excess Salt Increases Infarct Size Produced by Photothrombotic Middle Cerebral Artery Occlusion Without Increasing Blood Pressure in Spontaneously Hypertensive Rats

Stroke ◽  
2014 ◽  
Vol 45 (suppl_1) ◽  
Author(s):  
Hiroshi Yao ◽  
Toru Nabika
Keyword(s):  
Infarct Size ◽  
Brain Tissue ◽  
Infarct Volume ◽  
Artery Occlusion ◽  
Control Group ◽  
Salt Loading ◽  
Ischemic Brain ◽  
Spontaneously Hypertensive ◽  
Ischemic Brain Tissue ◽  
Cerebral Artery Occlusion

Background and Purpose: Cerebral circulation is known to be vulnerable to excess salt (e.g., impaired vasodilation, increased oxidative stress, accelerated spontaneous stroke, and enhanced blood-brain barrier [BBB] disruption). To our knowledge, however, no study has investigated the effects of excess salt on focal ischemic injury. Methods: After 14 days of salt loading or water, spontaneously hypertensive rats (SHR, Izumo strain, n=43) or normotensive Wistar-Kyoto rats (WKY, n=11) were subjected to photothrombotic middle cerebral artery occlusion (MCAO), and infarct volume was determined at 48 h after MCAO. Brain albumin and hemoglobin contents, as indices of BBB disruption, were determined with SELDI-TOF-MS in ischemic brain tissue. Effects of excess salt on the lower limits of cerebral blood flow (CBF) autoregulation were also determined. Results: Two-way analysis of variance confirmed a significant effect of saline on the volumes of drinking in SHR (p=0.000). Resting mean arterial blood pressure (BP) in SHR was 137±15 (S.D.) mmHg and 141±7 mmHg in the salt loading and control groups, respectively. After MCAO, regional CBF, determined with two ways of laser-Doppler flowmetry (one-point measurement or manual scanning), was more steeply decreased in the salt-loaded group than in the control group. In SHR, infarct volume in the salt-loaded group was 112±27 mm3, which was significantly larger than 77±12 mm3 in the control group (p=0.002), while albumin and hemoglobin levels in discrete brain regions were not different between the groups. In WKY, salt loading did not significantly increase infarct size. CBF response to hemorrhagic hypotension (i.e., autoregulation) was not affected by excess salt. Conclusions: We demonstrated that excess salt increased infarct size produced by photothrombotic MCAO without increasing BP in SHR but not in WKY. Excess salt did not deteriorate both vasogenic edema and hemorrhagic transformation of ischemic brain tissue after MCAO. The detrimental effects of excess salt were considered to be the result of compromised CBF in the ischemic brain tissue supplied by collateral circulation. A future study will investigate the mechanisms underlying the salt sensitivity to focal brain ischemia independent of BP changes.

scholarly journals Blockade and knock-out of CALHM1 channels attenuate ischemic brain damage

2017 ◽  
Vol 38 (6) ◽  
pp. 1060-1069 ◽  
Author(s):  
Abraham Cisneros-Mejorado ◽  
Miroslav Gottlieb ◽  
Asier Ruiz ◽  
Juan C Chara ◽  
Alberto Pérez-Samartín ◽  
...  
Keyword(s):  
Brain Damage ◽  
Therapeutic Potential ◽  
Infarct Volume ◽  
Atp Release ◽  
Artery Occlusion ◽  
Ruthenium Red ◽  
Ischemic Brain ◽  
Knock Out ◽  
Cerebral Artery Occlusion ◽  
Cortical Slices

Overactivation of purinergic receptors during cerebral ischemia results in a massive release of neurotransmitters, including adenosine triphosphate (ATP), to the extracellular space which leads to cell death. Some hypothetical pathways of ATP release are large ion channels, such as calcium homeostasis modulator 1 (CALHM1), a membrane ion channel that can permeate ATP. Since this transmitter contributes to postischemic brain damage, we hypothesized that CALHM1 activation may be a relevant target to attenuate stroke injury. Here, we analyzed the contribution of CALHM1 to postanoxic depolarization after ischemia in cultured neurons and in cortical slices. We observed that the onset of postanoxic currents in neurons in those preparations was delayed after its blockade with ruthenium red or silencing of Calhm1 gene by short hairpin RNA, as well as in slices from CALHM1 knockout mice. Subsequently, we used transient middle cerebral artery occlusion and found that ruthenium red, a blocker of CALHM1, or the lack of CALHM1, substantially attenuated the motor symptoms and reduced significantly the infarct volume. These results show that CALHM1 channels mediate postanoxic depolarization in neurons and brain damage after ischemia. Therefore, targeting CALHM1 may have a high therapeutic potential for treating brain damage after ischemia.

scholarly journals No Role for Interleukin-18 in Acute Murine Stroke-Induced Brain Injury

2003 ◽  
Vol 23 (5) ◽  
pp. 531-535 ◽  
Author(s):  
Rachel D. Wheeler ◽  
Herve Boutin ◽  
Omar Touzani ◽  
Giamal N. Luheshi ◽  
Kiyoshi Takeda ◽  
...  
Keyword(s):  
Middle Cerebral Artery ◽  
Middle Cerebral Artery Occlusion ◽  
Brain Damage ◽  
Cerebral Artery ◽  
Infarct Volume ◽  
Artery Occlusion ◽  
Interleukin 18 ◽  
Ischemic Brain Damage ◽  
Ischemic Brain ◽  
Cerebral Artery Occlusion

There is now extensive evidence to show that the cytokine interleukin-1 (IL-1) contributes directly to reversible and permanent ischemic brain damage in rodents. Because interleukin-18 (IL-18) shares many structural and functional similarities with IL-1, the authors tested the hypothesis that IL-18 contributes directly to ischemic brain damage in mice exposed to focal, reversible (15-minute or 30-minute) middle cerebral artery occlusion. IL-18 expression was not induced acutely by middle cerebral artery occlusion, and deletion of the IL-18 gene (IL-18 knockout mice) did not affect infarct volume. The present results suggest that IL-18 does not contribute to acute ischemic brain damage.

scholarly journals Long Course Hyperbaric Oxygen Stimulates Neurogenesis and Attenuates Inflammation after Ischemic Stroke

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Ying-Sheng Lee ◽  
Chung-Ching Chio ◽  
Ching-Ping Chang ◽  
Liang-Chao Wang ◽  
Po-Min Chiang ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Hyperbaric Oxygen ◽  
Artery Occlusion ◽  
Trophic Factors ◽  
Therapeutic Effects ◽  
Ischemic Brain ◽  
Neurological Severity Score ◽  
Group Mobilization ◽  
Long Course ◽  
Cerebral Artery Occlusion

Several studies have provided evidence with regard to the neuroprotection benefits of hyperbaric oxygen (HBO) therapy in cases of stroke, and HBO also promotes bone marrow stem cells (BMSCs) proliferation and mobilization. This study investigates the influence of HBO therapy on the migration of BMSCs, neurogenesis, gliosis, and inflammation after stroke. Rats that sustained transient middle cerebral artery occlusion (MCAO) were treated with HBO three weeks or two days. The results were examined using a behavior test (modified neurological severity score, mNSS) and immunostaining to evaluate the effects of HBO therapy on migration of BMSCs, neurogenesis, and gliosis, and expression of neurotrophic factors was also evaluated. There was a lower mNSS score in the three-week HBO group when compared with the two-day HBO group. Mobilization of BMSCs to an ischemic area was more improved in long course HBO treatments, suggesting the duration of therapy is crucial for promoting the homing of BMSCs to ischemic brain by HBO therapies. HBO also can stimulate expression of trophic factors and improve neurogenesis and gliosis. These effects may help in neuronal repair after ischemic stroke, and increasing the course of HBO therapy might enhance therapeutic effects on ischemic stroke.

Cortical Protection by Localized Striatal Injection of IL-1ra Following Cerebral Ischemia in the Rat

1997 ◽  
Vol 17 (6) ◽  
pp. 597-604 ◽  
Author(s):  
R. Paul Stroemer ◽  
Nancy J. Rothwell
Keyword(s):  
Cerebral Ischemia ◽  
Core Temperature ◽  
Infarct Volume ◽  
Interleukin 1 ◽  
Artery Occlusion ◽  
Protective Effects ◽  
Ischemic Brain ◽  
Cortical Damage ◽  
Sites Of Action ◽  
Cerebral Artery Occlusion

Interleukin-1 (IL-1) receptor antagonist (IL-1ra) markedly reduces infarct volume induced by middle cerebral artery occlusion (MCAO) in the rat, when injected either centrally (intracerebroventricularly) or peripherally. The site or sites of action of IL-1 in stroke pathology, however, are not known. The present study investigated the site(s) of action of IL-1/IL-1ra in ischemic brain damage by studying the effects of local injection of IL-1ra into the cortex or striatum following permanent MCAO in the rat. Cortical injection of IL-1ra (5 µg) did not affect infarct volume in the cortex or striatum measured 24 h after MCAO. In contrast, striatal injection of IL-1ra ipsilateral to the infarction caused a significant and highly reproducible reduction of cortical (37%, p < 0.001) and striatal damage (27%, p < 0.001, corrected for edema) compared with vehicle-injected animals. Injection of IL-1ra (5 µg) into the striatum, contralateral to the infarction, resulted in a small (9%) but significant (p < 0.001) reduction of ipsilateral cortical damage, with no effect on ipsilateral striatal damage. Injection of a higher dose of IL-1ra (7.5 µg) in the contralateral striatum caused a further inhibition of ipsilateral cortical damage (24%, p < 0.001) and a significant reduction of ipsilateral striatal damage (16%, p < 0.001). In separate groups of rats, it was established that core temperature (measured continuously in free-moving animals with remote radiotelemetry) was not affected by striatal or cortical injection of IL-1ra. These data show that injection of IL-1ra into the striatum but not the cortex reduces infarct volume in both the striatum and the cortex, independently of effects on core temperature. These results imply that blocking striatal IL-1 contributes to IL-1ra-protective effects. We hypothesize that IL-1 may influence striatal distal cortical damage through either the release of specific substances or activation of polysynaptic pathways.

scholarly journals Postischemic Administration of AK275, a Calpain Inhibitor, Provides Substantial Protection against Focal Ischemic Brain Damage

1994 ◽  
Vol 14 (4) ◽  
pp. 537-544 ◽  
Author(s):  
Raymond T. Bartus ◽  
Keith L. Baker ◽  
Angie D. Heiser ◽  
Sean D. Sawyer ◽  
Reginald L. Dean ◽  
...  
Keyword(s):  
Brain Damage ◽  
Infarct Volume ◽  
Neuroprotective Effect ◽  
Focal Ischemia ◽  
Artery Occlusion ◽  
Calpain Inhibitor ◽  
Ischemic Brain Damage ◽  
Ischemic Brain ◽  
Diastereomeric Mixture ◽  
Cerebral Artery Occlusion

Experiments were conducted to determine whether a potent, reversible calpain inhibitor could reduce the cortical ischemic brain damage associated with focal ischemia in the rat. AK275 (Z-Leu–Abu–CONH–CH2CH3), the active isomer of the diastereomeric mixture, CX275, was employed in conjunction with a novel method of perfusing drug directly onto the infarcted cortical surface. This protocol reduced or eliminated numerous, nonspecific pharmacokinetic, hemodynamic, and other potentially confounding variables that might complicate interpretation of any drug effect. Focal ischemia was induced using a variation of the middle cerebral artery occlusion method. These studies demonstrated a reliable and robust neuroprotective effect of AK275 over the concentration range of 10 to 200 μ M (perfused supracortically at 4 μl/h for 21 h). Moreover, a 75% reduction in infarct volume was observed when initiation of drug treatment was delayed for 3 h postocclusion. Our data further support an important role of calpain in ischemia-induced neuropathology and suggest that calpain inhibitors may provide a unique and potentially powerful means of treating stroke and other ischemic brain incidents.

scholarly journals Effect of Electroacupuncture on Rat Ischemic Brain Injury: Importance of Stimulation Duration

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Fei Zhou ◽  
Jingchun Guo ◽  
Jieshi Cheng ◽  
Gencheng Wu ◽  
Ying Xia
Keyword(s):  
Blood Flow ◽  
Death Rate ◽  
Infarct Volume ◽  
Ischemic Injury ◽  
Artery Occlusion ◽  
Neurological Deficits ◽  
Ischemic Brain ◽  
Cell Velocity ◽  
Short Period ◽  
Cerebral Artery Occlusion

We explored the optimal duration of electroacupuncture (EA) stimulation for protecting the brain against ischemic injury. The experiments were carried out in rats exposed to right middle cerebral artery occlusion (MCAO) for 60 min followed by 24-hr reperfusion. EA was delivered to “Shuigou” (Du 26) and “Baihui” (Du 20) acupoints with sparse-dense wave (5/20 Hz) at 1.0 mA for 5, 15, 30, and 45 min, respectively. The results showed that 30 min EA, starting at 5 minutes after the onset of MCAO (EA during MCAO) or 5 minutes after reperfusion (EA after MCAO), significantly reduced ischemic infarct volume, attenuated neurological deficits, and decreased death rate with a larger reduction of the ischemic infarction in the former group. Also in the group of EA during MCAO, this protective benefit was positively proportional to the increase in the period of stimulation, that is, increased protection in response to EA from 5- to 30-min stimulation. In all groups, EA induced a significant increase in cerebral blood flow and promoted blood flow recovery after reperfusion, and both blood flow volume and blood cell velocity returned to the preischemia level in a short period of time. Surprisingly, EA for 45 min did not show reduction in the neurological deficits or the infarct volume and instead demonstrated an increase in death rate in this group. Although EA for 45 min still increased the blood flow during MCAO, it led to a worsening of perfusion after reperfusion compared to the group subjected only to ischemia. The neuroprotection induced by an “optimal” period (30 min) of EA was completely blocked by Naltrindole, aδ-opioid receptor (DOR) antagonist (10 mg/kg, i.v.). These findings suggest that earlier EA stimulation leads to better outcomes, and that EA-induced neuroprotection against ischemia depends on an optimal EA-duration via multiple pathways including DOR signaling, while “over-length” stimulation exacerbates the ischemic injury.

scholarly journals Exacerbation of Ischemic Brain Damage by Localized Striatal Injection of Interleukin-1β in the Rat

1998 ◽  
Vol 18 (8) ◽  
pp. 833-839 ◽  
Author(s):  
R. Paul Stroemer ◽  
Nancy J. Rothwell
Keyword(s):  
Body Temperature ◽  
Middle Cerebral Artery ◽  
Middle Cerebral Artery Occlusion ◽  
Brain Damage ◽  
Infarct Volume ◽  
Artery Occlusion ◽  
Ischemic Damage ◽  
Ischemic Brain ◽  
Site Of Action ◽  
Cerebral Artery Occlusion

Interleukin-1β (IL-1β) has been implicated in ischemic brain damage. The site of action of IL-1β in such damage is not known, but we have demonstrated previously that injection of the interleukin-1 receptor antagonist (IL-1ra) in the striatum but not the cortex of rats inhibits damage caused by permanent middle cerebral artery occlusion. The present study investigated the site of action of IL-1β on ischemic damage by examining the effects of intracerebroventricular, striatal, or cortical injection of recombinant IL-1β at the onset of permanent middle cerebral artery occlusion in the rat. Intracerebroventricular injection of IL-1β (2.5 ng) significantly increased infarct volume in the striatum (35%, P < 0.0001) and in the cortex (44%, P < 0.0001) compared with vehicle treatment. Direct injection of IL-1β into the striatum also increased infarct volume in both the striatum (36%, P < 0.0001) and the cortex (38%, P < 0.0001), whereas injection of IL-1β into the cortex failed to affect infarct volume in either the striatum or the cortex. Cortical injection of a higher dose of IL-1β (20 ng) also failed to affect ischemic damage in either the striatum or the cortex. Injection of IL-1β into the striatum contralateral to the infarction had no effect on striatal damage in the ischemic hemisphere, but did increase cortical damage by 18% ( P < 0.0001). In separate groups of animals, IL-1β (2.5 ng) was injected into either the striatum or the cortex, and body temperature was recorded continuously in conscious free-moving animals by remote telemetry. Injection of IL-1β at either site failed to influence body temperature, suggesting that exacerbation of brain damage by striatal injection of IL-1β is not caused by effects on body temperature. These results imply that IL-1β exacerbates ischemic damage by specific actions in the striatum where it can influence damage at distant sites in the cortex.

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