1
|
Nash C, Powell K, Lynch DG, Hartings JA, Li C. Nonpharmacological modulation of cortical spreading depolarization. Life Sci 2023:121833. [PMID: 37302793 DOI: 10.1016/j.lfs.2023.121833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 06/01/2023] [Accepted: 06/03/2023] [Indexed: 06/13/2023]
Abstract
AIMS Cortical spreading depolarization (CSD) is a wave of pathologic neuronal dysfunction that spreads through cerebral gray matter, causing neurologic disturbance in migraine and promoting lesion development in acute brain injury. Pharmacologic interventions have been found to be effective in migraine with aura, but their efficacy in acutely injured brains may be limited. This necessitates the assessment of possible adjunctive treatments, such as nonpharmacologic methods. This review aims to summarize currently available nonpharmacological techniques for modulating CSDs, present their mechanisms of action, and provide insight and future directions for CSD treatment. MAIN METHODS A systematic literature review was performed, generating 22 articles across 3 decades. Relevant data is broken down according to method of treatment. KEY FINDINGS Both pharmacologic and nonpharmacologic interventions can mitigate the pathological impact of CSDs via shared molecular mechanisms, including modulating K+/Ca2+/Na+/Cl- ion channels and NMDA, GABAA, serotonin, and CGRP ligand-based receptors and decreasing microglial activation. Preclinical evidence suggests that nonpharmacologic interventions, including neuromodulation, physical exercise, therapeutic hypothermia, and lifestyle changes can also target unique mechanisms, such as increasing adrenergic tone and myelination and modulating membrane fluidity, which may lend broader modulatory effects. Collectively, these mechanisms increase the electrical initiation threshold, increase CSD latency, slow CSD velocity, and decrease CSD amplitude and duration. SIGNIFICANCE Given the harmful consequences of CSDs, limitations of current pharmacological interventions to inhibit CSDs in acutely injured brains, and translational potentials of nonpharmacologic interventions to modulate CSDs, further assessment of nonpharmacologic modalities and their mechanisms to mitigate CSD-related neurologic dysfunction is warranted.
Collapse
Affiliation(s)
- Christine Nash
- Translational Brain Research Laboratory, The Feinstein Institutes for Medical Research, Manhasset, NY, USA; Barnard College, New York, NY, USA
| | - Keren Powell
- Translational Brain Research Laboratory, The Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Daniel G Lynch
- Translational Brain Research Laboratory, The Feinstein Institutes for Medical Research, Manhasset, NY, USA; Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
| | - Jed A Hartings
- Department of Neurosurgery, University of Cincinnati, Cincinnati, OH, USA
| | - Chunyan Li
- Translational Brain Research Laboratory, The Feinstein Institutes for Medical Research, Manhasset, NY, USA; Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA; Department of Neurosurgery, Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA.
| |
Collapse
|
2
|
Ma H, Zhai Y, Xu Z, Fan S, Wu X, Xu J, Wu S, Ma C. Increased cerebral cortex activation in stroke patients during electrical stimulation of cerebellar fastigial nucleus with functional near-infrared spectroscopy. Front Neurosci 2022; 16:895237. [PMID: 36061594 PMCID: PMC9433974 DOI: 10.3389/fnins.2022.895237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 07/25/2022] [Indexed: 11/17/2022] Open
Abstract
Background Electrical stimulation of the cerebellar fastigial nucleus (FNS) has been shown to protect animals against cerebral ischemic injury. However, the changes in cortical activation as a response to FNS have not been illustrated in humans. Objective This study aims to detect functional connectivity changes in the brain of stroke patients, and investigate the cortical activation caused by FNS through measuring the oxygenated hemoglobin concentration (HBO) in the cerebral cortex of stroke patients and healthy controls (HCs). Methods This study recruited 20 patients with stroke and 20 HCs with all the following factors matched: age, gender and BMI. The experiment session was made up of the pre-task baseline, FNS task period, and post-task baseline. FNS task period contains 5 blocks, each block encompassing the resting state (30 s) and the FNS state (30 s). HBO signals were acquired by functional near-infrared spectroscopy (fNIRS) from the Prefrontal Cortex (PFC), the Motor Cortex (MC) and the Occipital Cortex (OC) throughout the experiment. The Pearson correlation coefficient was used to calculate the resting-state functional connectivity strength between the two groups, and the general linear model (GLM) was used to calculate the activation of 39 fNIRS channels during FNS in stroke patients and HCs, respectively. Results The coupling strength of stroke patients were significantly decreased in the following regions: right MC and left MC (t = 4.65, p = 0.0007), right MC and left OC (t = 2.93, p = 0.04), left MC and left OC (t = 2.81, p = 0.04). In stroke patients, the changes in cerebral oxygenated hemoglobin (ΔHBO) among 12 channels (CH) in the bilateral PFC and bilateral MC regions were significantly increased during the FNS state (FDR corrected p < 0.05) compared with the resting state. In HCs, only 1 channel was increased (FDR corrected p < 0.05) in the left PFC during FNS. Conclusion By using the FNS and fNIRS techniques, the characteristics of functional connectivity were found to decrease in stroke patients. It was also noticed that FNS activates the PFC and MC regions. These findings may help to guide functional rehabilitation in stroke patients.
Collapse
|
3
|
Abstract
PURPOSE OF REVIEW The past two decades has seen an influx of noninvasive neuromodulation devices aimed at treatment of various primary headache disorders, including cluster headache and migraine. This narrative review is to summarize the current options in noninvasive neuromodulation in migraine. RECENT FINDINGS A variety of noninvasive neuromodulation devices have been FDA cleared and marketed for use in migraine, including single-pulse transcranial magnetic stimulation (sTMS), noninvasive vagal nerve stimulators (nVNS), and external trigeminal nerve stimulators (eTNS). Newer devices include peripheral electrical stimulation devices (PES), caloric stimulation, and others. Each has varying levels of evidence supporting its use in migraine, tolerability profiles, and access issues. Noninvasive neuromodulation devices can be beneficial when used in patients with migraine, with minimal side effects. As more devices are developed, approved, and marketed in the future, rigorous research on efficacy and safety remain a top priority.
Collapse
|
4
|
Vagus nerve stimulation reduces spreading depolarization burden and cortical infarct volume in a rat model of stroke. PLoS One 2020; 15:e0236444. [PMID: 32702055 PMCID: PMC7377493 DOI: 10.1371/journal.pone.0236444] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 07/06/2020] [Indexed: 01/30/2023] Open
Abstract
Cortical spreading depolarization (SD) waves negatively affect neuronal survival and outcome after ischemic stroke. We here aimed to investigate the effects of vagus nerve stimulation (VNS) on SDs in a rat model of focal ischemia. To this end, we delivered non-invasive VNS (nVNS) or invasive VNS (iVNS) during permanent middle cerebral artery occlusion (MCAO), and found that both interventions significantly reduced the frequency of SDs in the cortical peri-infarct area compared to sham VNS, without affecting relative blood flow changes, blood pressure, heart rate or breathing rate. In separate groups of rats subjected to transient MCAO, we found that cortical stroke volume was reduced 72 h after transient MCAO, whereas stroke volume in the basal ganglia remained unchanged. In rats treated with nVNS, motor outcome was improved 2 days after transient MCAO, but was similar to sham VNS animals 3 days after ischemia. We postulate that VNS may be a safe and efficient intervention to reduce the clinical burden of SD waves in stroke and other conditions.
Collapse
|
5
|
Bahr-Hosseini M, Saver JL. Mechanisms of action of acute and subacute sphenopalatine ganglion stimulation for ischemic stroke. Int J Stroke 2020; 15:839-848. [PMID: 32326842 DOI: 10.1177/1747493020920739] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND Sphenopalatine ganglion stimulation (SPG-Stim) for ischemic stroke, starting 8-24 h after onset and continuing through five days in a pooled analysis of two recent, randomized, sham-controlled trials, improved outcome of acute ischemic stroke patients with confirmed cortical involvement. As a neuromodulatory therapy, SPG-Stim differs substantially from existing pharmacologic (lytic and antiplatelets) and device (endovascular thrombectomy) acute ischemic stroke treatments. AIM Focused review of SPG anatomy, physiology, and neurovascular and neurobiologic mechanisms of action mediating benefit of SPG-Stim in acute ischemic stroke. SUMMARY OF REVIEW Located posterior to the maxillary sinus, the SPG is the main source of parasympathetic innervation to the anterior circulation. Preclinical and human studies delineate four distinct mechanisms of action by which the SPG-Stim may confer benefit in acute ischemic stroke: (1) collateral vasodilation and enhanced cerebral blood flow, mediated by release of neurotransmitters with vasodilatory effects, nitric oxide, and acetylcholine, (2) stimulation frequency- and intensity-dependent stabilization of the blood-brain barrier, reducing edema (3) direct acute neuroprotection from activation of the central cholinergic system with resulting anti-inflammatory, anti-apoptotic, and anti-excitatory effects; and (4) neuroplasticity enhancement from enhanced central cholinergic and adrenergic neuromodulation of cortical networks and nitrous oxide release stimulating neurogenesis. CONCLUSION The benefit of SPG-Stim in acute ischemic stroke is likely conferred not only by potent collateral augmentation, but also blood-barrier stabilization, direct neuroprotection, and neuroplasticity enhancement. Further studies clarifying the relative contribution of these mechanisms and the stimulation protocols that maximize each may help optimize SPG-Stim as a therapy for acute ischemic stroke.
Collapse
Affiliation(s)
- Mersedeh Bahr-Hosseini
- Department of Neurology and Comprehensive Stroke Center, David Geffen School of Medicine at 8783UCLA, Los Angeles, CA, USA
| | - Jeffrey L Saver
- Department of Neurology and Comprehensive Stroke Center, David Geffen School of Medicine at 8783UCLA, Los Angeles, CA, USA
| |
Collapse
|
6
|
Deng Y, Zheng M, He L, Yang J, Yu G, Wang J. A Head-to-Head Comparison of Percutaneous Mastoid Electrical Stimulator and Supraorbital Transcutaneous Stimulator in the Prevention of Migraine: A Prospective, Randomized Controlled Study. Neuromodulation 2020; 23:770-777. [PMID: 32096902 DOI: 10.1111/ner.13127] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 01/07/2020] [Accepted: 02/03/2020] [Indexed: 11/30/2022]
Abstract
INTRODUCTION This prospective, randomized, multicenter head-to-head outcome study was performed to compare the efficacy and safety of Percutaneous Mastoid Electrical Stimulator (PMES) and Supraorbital Transcutaneous Stimulator (STS) in migraine prevention. METHODS This was a prospective, randomized, head-to-head outcome study that involved three medical centers. After a one-month run-in, episodic patients with at least two migraine attacks/month were randomized to receive PMES daily for 45 min or STS daily for 20 min for three months. The primary outcomes were change in monthly migraine days and the 50% response rate. RESULTS A total of 90 patients were included in this study. We observed statistically significant reduction of migraine days in the third month treatment both in the PMES group and STS group. The difference between the two groups was not significant (60.5% vs. 53.8%, p = 0.88). Of note, 77.8% patients in the PMES group and 62.2% patients in the STS group had a ≥50% reduction of migraine days in the third month (p = 0.070). The change in monthly migraine days, monthly migraine attacks, severity of migraine days, accompanying symptoms during migraine and monthly acute anti-migraine drug intake were not significantly different between the two groups. The change of Headache Impact Test-6 (HIT-6) from run-in to the third-month treatment in the STS group was more remarkable than that in the PMES group (36.5% vs. 25.6%, p = 0.041). The occurrence of discomfort paresthesia was higher in the STS group (13.3% vs. 0%, p = 0.026). CONCLUSION PMES and STS treatment were both effective in migraine prevention. The safety and efficacy of PMES and STS were comparable.
Collapse
Affiliation(s)
- Yushuang Deng
- Department of Neurology, The Second People's Hospital of Chengdu, Chengdu, People's Republic of China
| | - Min Zheng
- School of Medicine, University of Electronic Science and Technology of China, Chengdu, People's Republic of China
| | - Lanying He
- Department of Neurology, The Second People's Hospital of Chengdu, Chengdu, People's Republic of China
| | - Juan Yang
- Department of Neurology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China
| | - Gang Yu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China
| | - Jian Wang
- Department of Neurology, The Second People's Hospital of Chengdu, Chengdu, People's Republic of China
| |
Collapse
|
7
|
Bahr Hosseini M, Hou J, Bikson M, Iacoboni M, Gornbein J, Saver JL. Central Nervous System Electrical Stimulation for Neuroprotection in Acute Cerebral Ischemia: Meta-Analysis of Preclinical Studies. Stroke 2019; 50:2892-2901. [PMID: 31480966 DOI: 10.1161/strokeaha.119.025364] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Background and Purpose- Brain electrical stimulation, widely studied to facilitate recovery from stroke, has also been reported to confer direct neuroprotection in preclinical models of acute cerebral ischemia. Systematic review of controlled preclinical acute cerebral ischemia studies would aid in planning for initial human clinical trials. Methods- A systematic Medline search identified controlled, preclinical studies of central nervous system electrical stimulation in acute cerebral ischemia. Studies were categorized among 6 stimulation strategies. Three strategies applied different stimulation types to tissues within the ischemic zone (cathodal hemispheric stimulation [CHS], anodal hemispheric stimulation, and pulsed hemispheric stimulation), and 3 strategies applied deep brain stimulation to different neuronal targets remote from the ischemic zone (fastigial nucleus stimulation, subthalamic vasodilator area stimulation, and dorsal periaqueductal gray stimulation). Random-effects meta-analysis assessed electrical stimulation modification of final infarct volume. Study-level risk of bias and intervention-level readiness-for-translation were assessed using formal rating scales. Results- Systematic search identified 28 experiments in 21 studies, including a total of 350 animals, of electrical stimulation in preclinical acute cerebral ischemia. Overall, in animals undergoing electrical stimulation, final infarct volumes were reduced by 37% (95% CI, 34%-40%; P<0.001), compared with control. There was evidence of heterogeneity of efficacy among stimulation strategies (I2=93.1%, Pheterogeneity<0.001). Among the within-ischemic zone stimulation strategies, only CHS significantly reduced the infarct volume (27 %; 95% CI, 22%-33%; P<0.001); among the remote-from ischemic zone approaches, all (fastigial nucleus stimulation, subthalamic vasodilator area stimulation, and dorsal periaqueductal gray stimulation) reduced infarct volumes by approximately half. On formal rating scales, CHS studies had the lowest risk of bias, and CHS had the highest overall quality of intervention-level evidence supporting readiness to proceed to clinical testing. Conclusions- Electrical stimulation reduces final infarct volume across preclinical studies. CHS shows the most robust evidence and is potentially appropriate for progression to early-stage human clinical trial testing as a promising neuroprotective intervention.
Collapse
Affiliation(s)
- Mersedeh Bahr Hosseini
- From the Department of Neurology and Comprehensive Stroke Center (M.B.H., J.H., J.L.S.), David Geffen School of Medicine at UCLA
| | - Jesse Hou
- From the Department of Neurology and Comprehensive Stroke Center (M.B.H., J.H., J.L.S.), David Geffen School of Medicine at UCLA
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York (CCNY) (M.B.)
| | - Marco Iacoboni
- Department of Psychiatry and Biobehavioral Sciences (M.I.), David Geffen School of Medicine at UCLA
| | - Jeffrey Gornbein
- Department of Biomedical Engineering, The City College of New York (CCNY) (M.B.)
| | - Jeffrey L Saver
- From the Department of Neurology and Comprehensive Stroke Center (M.B.H., J.H., J.L.S.), David Geffen School of Medicine at UCLA
| |
Collapse
|
8
|
Abstract
Vagus nerve stimulation has recently been reported to improve symptoms of migraine. Cortical spreading depression is the electrophysiological event underlying migraine aura and is a trigger for headache. We tested whether vagus nerve stimulation inhibits cortical spreading depression to explain its antimigraine effect. Unilateral vagus nerve stimulation was delivered either noninvasively through the skin or directly by electrodes placed around the nerve. Systemic physiology was monitored throughout the study. Both noninvasive transcutaneous and invasive direct vagus nerve stimulations significantly suppressed spreading depression susceptibility in the occipital cortex in rats. The electrical stimulation threshold to evoke a spreading depression was elevated by more than 2-fold, the frequency of spreading depressions during continuous topical 1 M KCl was reduced by ∼40%, and propagation speed of spreading depression was reduced by ∼15%. This effect developed within 30 minutes after vagus nerve stimulation and persisted for more than 3 hours. Noninvasive transcutaneous vagus nerve stimulation was as efficacious as direct invasive vagus nerve stimulation, and the efficacy did not differ between the ipsilateral and contralateral hemispheres. Our findings provide a potential mechanism by which vagus nerve stimulation may be efficacious in migraine and suggest that susceptibility to spreading depression is a suitable platform to optimize its efficacy.
Collapse
|
9
|
Juan Y, Shu O, Jinhe L, Na Y, Yushuang D, Weiwei D, Lanying H, Jian W. Migraine prevention with percutaneous mastoid electrical stimulator: A randomized double-blind controlled trial. Cephalalgia 2016; 37:1248-1256. [PMID: 27821639 DOI: 10.1177/0333102416678623] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objective To evaluate the effectiveness and safety of episodic migraine prevention with the percutaneous mastoid electrical stimulator (PMES). Methods This was a randomized, double-blind, and sham-controlled trial that involved four medical centers. Episodic patients with at least two migraine attacks every month were randomly 1:1 to PMES or sham stimulation treatment. The treatments were performed daily for 45 minutes over 3 months. The primary outcomes were change in migraine days per month and the 50% response rate. Results The PMES group had a significantly greater reduction of migraine days in the third month than the sham group (-71.3% vs. -14.4%, p < 0.001). The 50% response rate of migraine days in the PMES group (≥50% reduction of migraine days compared with the baseline) was significantly higher than that in the sham group (82.5% vs. 17.5%, p < 0.001). In the PMES group, 60% of the patients had a ≥75% reduction of migraine days in the third month, and 35% of the patients had no migraine attack in the third month. No patients in the sham group had a ≥75% reduction of migraine days. There were no adverse events in either group. Conclusion Treatment of migraine using non-invasive PMES was safe and effective.
Collapse
Affiliation(s)
- Yang Juan
- 1 Department of Neurology, The Second People's Hospital of Chengdu, Chengdu, China
| | - Ou Shu
- 2 Department of Neurology, The Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Lou Jinhe
- 3 Department of Neurology, The First Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Yang Na
- 4 Department of Neurology, Chongqing Emergency Medical Center, Chongqing, China
| | - Deng Yushuang
- 1 Department of Neurology, The Second People's Hospital of Chengdu, Chengdu, China
| | - Dong Weiwei
- 3 Department of Neurology, The First Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - He Lanying
- 1 Department of Neurology, The Second People's Hospital of Chengdu, Chengdu, China
| | - Wang Jian
- 1 Department of Neurology, The Second People's Hospital of Chengdu, Chengdu, China
| |
Collapse
|
10
|
Preconditioning cortical lesions reduce the incidence of peri-infarct depolarizations during focal ischemia in the Spontaneously Hypertensive Rat: interaction with prior anesthesia and the impact of hyperglycemia. J Cereb Blood Flow Metab 2015; 35:1181-90. [PMID: 25757750 PMCID: PMC4640273 DOI: 10.1038/jcbfm.2015.37] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 01/16/2015] [Accepted: 02/08/2015] [Indexed: 02/07/2023]
Abstract
The relationship between peri-infarct depolarizations (PIDs) and infarction was investigated in a model of preconditioning by cortical freeze lesions (cryogenic lesions, CL) in the Spontaneously Hypertensive Rat. Small (< 5 mm(3)) lesions produced 24 hours before permanent focal ischemia were protective, without impacting baseline cerebral blood flow (CBF) and metabolism. Prior CL reduced infarct volume, associated with improved penumbral CBF as previously showed for ischemic preconditioning. The brief initial procedure avoided sham effects on infarct volume after subsequent occlusion under brief anesthesia. However, under prolonged isoflurane anesthesia for perfusion monitoring both sham and CL rats showed reduced PID incidence relative to naive animals. This anesthesia effect could be eliminated by using α-chloralose during perfusion imaging. As an additional methodological concern, blood glucose was frequently elevated at the time of the second surgery, reflecting buprenorphine-induced pica and other undefined mechanisms. Even modest hyperglycemia (>10 mmol/L) reduced PID incidence. In normoglycemic animals CL preconditioning reduced PID number by 50%, demonstrating associated effects on PID incidence, penumbral perfusion, and infarct progression. Hyperglycemia suppressed PIDs without affecting the relationship between CBF and infarction. This suggests that the primary effect of preconditioning is to improve penumbral perfusion, which in turn impacts PID incidence and infarct size.
Collapse
|
11
|
Wang J, Dong WW, Zhang WH, Zheng J, Wang X. Electrical stimulation of cerebellar fastigial nucleus: mechanism of neuroprotection and prospects for clinical application against cerebral ischemia. CNS Neurosci Ther 2014; 20:710-6. [PMID: 24930936 DOI: 10.1111/cns.12288] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2014] [Revised: 04/28/2014] [Accepted: 05/01/2014] [Indexed: 12/18/2022] Open
Abstract
For around two decades, electrical fastigial nucleus stimulation (FNS) has been demonstrated to induce neuroprotection involving multiple mechanisms. In this review, we summarize the protective effects of FNS against cerebral ischemia through the inhibition of electrical activity around the lesion, excitotoxic damage on neurons, and brain inflammatory response, as well as apoptosis. Moreover, FNS has been reported to promote nerve tissue repair, reconstruction, and neurological rehabilitation and improve stroke-related complications including poststroke cognitive dysfunction, depression, and abnormal heart rate variability. We thus further discuss the potential of FNS for clinical applications. Given the absence of any risk of inducing sublethal damage, FNS may offer a new approach to preconditioned neuroprotection against cerebral ischemia.
Collapse
Affiliation(s)
- Jian Wang
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Department of Neurology, The Second People's Hospital of Chengdu, Chengdu, Sichuan, China
| | | | | | | | | |
Collapse
|
12
|
Fastigial Nucleus Electrostimulation Reduces the Expression of Repulsive Guidance Molecule, Improves Axonal Growth Following Focal Cerebral Ischemia. Neurochem Res 2012; 37:1906-14. [DOI: 10.1007/s11064-012-0809-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Revised: 04/29/2012] [Accepted: 05/26/2012] [Indexed: 02/04/2023]
|
13
|
Abstract
Abstract
Collapse
|
14
|
Takahashi M, Zhang ZD, Macdonald RL. Sphenopalatine ganglion stimulation for vasospasm after experimental subarachnoid hemorrhage. J Neurosurg 2011; 114:1104-9. [DOI: 10.3171/2010.6.jns091525] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Sphenopalatine ganglion stimulation activates perivascular vasodilatory nerves in the ipsilateral anterior circle of Willis. This experiment tested whether stimulation of the ganglion could reverse vasospasm and improve cerebral perfusion after subarachnoid hemorrhage (SAH) in monkeys.
Methods
Thirteen cynomolgus monkeys underwent baseline angiography followed by creation of SAH by placement of autologous blood against the right intradural internal carotid artery, the middle cerebral artery (MCA), and the anterior cerebral artery. Seven days later, angiography was repeated, and the right sphenopalatine ganglion was exposed microsurgically. Angiography was repeated 15 minutes after exposure of the ganglion. The ganglion was stimulated electrically 3 times, and angiography was repeated during and 15 and 30 minutes after stimulation. Cerebral blood flow (CBF) was monitored using laser Doppler flowmetry, and intracranial pressure (ICP) was measured throughout. The protocol was repeated again. Evans blue was injected and the animals were killed. The brains were removed for analysis of water and Evans blue content and histology.
Results
Subarachnoid hemorrhage was associated with significant vasospasm of the ipsilateral major cerebral arteries (23% ± 10% to 39% ± 4%; p < 0.05, paired t-tests). Exposure of the ganglion and sham stimulation had no significant effects on arterial diameters, ICP, or CBF (4 monkeys, ANOVA and paired t-tests). Sphenopalatine ganglion stimulation dilated the ipsilateral extracranial and intracranial internal carotid artery, MCA, and anterior cerebral artery compared with the contralateral arteries (9 monkeys, 7% ± 9% to 15% ± 19%; p < 0.05, ANOVA). There was a significant increase in ipsilateral CBF. Stimulation had no effect on ICP or brain histology. Brain water content did not increase but Evans blue content was significantly elevated in the MCA territory of the stimulated hemisphere.
Conclusions
Sphenopalatine ganglion stimulation decreased vasospasm and increased CBF after SAH in monkeys. This was associated with opening of the blood-brain barrier.
Collapse
Affiliation(s)
- Masataka Takahashi
- 1Section of Neurosurgery, Department of Surgery, University of Chicago Medical Center and Pritzker School of Medicine, Chicago, Illinois; and
| | - Zhen-Du Zhang
- 1Section of Neurosurgery, Department of Surgery, University of Chicago Medical Center and Pritzker School of Medicine, Chicago, Illinois; and
| | - R. Loch Macdonald
- 2Division of Neurosurgery, St. Michael's Hospital, Keenan Research Centre in the Li Ka Shing Knowledge Institute of St. Michael's Hospital and Department of Surgery, University of Toronto, Ontario, Canada
| |
Collapse
|
15
|
Vagus nerve stimulation reduces infarct size in rat focal cerebral ischemia. Neurosci Lett 2009; 459:147-51. [DOI: 10.1016/j.neulet.2009.05.018] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Revised: 04/30/2009] [Accepted: 05/06/2009] [Indexed: 11/21/2022]
|
16
|
Obrenovitch TP. Molecular physiology of preconditioning-induced brain tolerance to ischemia. Physiol Rev 2008; 88:211-47. [PMID: 18195087 DOI: 10.1152/physrev.00039.2006] [Citation(s) in RCA: 170] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Ischemic tolerance describes the adaptive biological response of cells and organs that is initiated by preconditioning (i.e., exposure to stressor of mild severity) and the associated period during which their resistance to ischemia is markedly increased. This topic is attracting much attention because preconditioning-induced ischemic tolerance is an effective experimental probe to understand how the brain protects itself. This review is focused on the molecular and related functional changes that are associated with, and may contribute to, brain ischemic tolerance. When the tolerant brain is subjected to ischemia, the resulting insult severity (i.e., residual blood flow, disruption of cellular transmembrane gradients) appears to be the same as in the naive brain, but the ensuing lesion is substantially reduced. This suggests that the adaptive changes in the tolerant brain may be primarily directed against postischemic and delayed processes that contribute to ischemic damage, but adaptive changes that are beneficial during the subsequent test insult cannot be ruled out. It has become clear that multiple effectors contribute to ischemic tolerance, including: 1) activation of fundamental cellular defense mechanisms such as antioxidant systems, heat shock proteins, and cell death/survival determinants; 2) responses at tissue level, especially reduced inflammatory responsiveness; and 3) a shift of the neuronal excitatory/inhibitory balance toward inhibition. Accordingly, an improved knowledge of preconditioning/ischemic tolerance should help us to identify neuroprotective strategies that are similar in nature to combination therapy, hence potentially capable of suppressing the multiple, parallel pathophysiological events that cause ischemic brain damage.
Collapse
Affiliation(s)
- Tihomir Paul Obrenovitch
- Division of Pharmacology, School of Life Sciences, University of Bradford, Bradford, United Kingdom.
| |
Collapse
|
17
|
Henninger N, Fisher M. Stimulating Circle of Willis Nerve Fibers Preserves the Diffusion-Perfusion Mismatch in Experimental Stroke. Stroke 2007; 38:2779-86. [PMID: 17761922 DOI: 10.1161/strokeaha.107.485581] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background and Purpose—
Stimulation of the nerves traversing the ethmoidal foramen (including postsynaptic, parasympathetic projections from the sphenopalatine ganglion [SPG], henceforth referred to as “SPG-stimulation”) has been shown to elevate cerebral blood flow (CBF) and to be neuroprotective after permanent, middle cerebral artery occlusion (pMCAO).
Methods—
Employing diffusion (DWI)- and perfusion (PWI) weighted MRI, the effect of SPG-stimulation (started at 60 minutes post-MCAO) on the spatiotemporal evolution of ischemia during and after pMCAO was investigated. In an additional experiment, regional CBF changes were investigated in the nonischemic brain.
Results—
In the nonischemic brain, SPG stimulation significantly elevated CBF predominantly within areas supplied by the anterior cerebral artery (by 0.64 mL/g/min relative to baseline). In the ischemic brain, CBF only marginally increased within the penumbra and core (by up to 0.08 and 0.15 mL/g/min relative to prestimulation, respectively). However, the threshold-derived CBF lesion volume did not change significantly. Penumbral apparent diffusion coefficient (ADC)-values improved to almost baseline values and the threshold derived ADC/CBF-mismatch was preserved up to 180 minutes after MCAO. TTC-derived lesion volumes were significantly smaller in stimulated versus nonstimulated animals (120.4±74.1 mm
3
versus 239.3±68.5 mm
3
, respectively).
Conclusion—
This study demonstrates that unilateral SPG-stimulation increases CBF bilaterally within the normal brain, acutely preserves the CBF/ADC mismatch largely independent of altering cerebral blood flow, and reduces infarct size in the rat permanent suture model.
Collapse
Affiliation(s)
- Nils Henninger
- Department of Medicine, University of Massachusetts Medical School, 55 Lake Ave, North, Worcester, MA 01655, USA.
| | | |
Collapse
|
18
|
Dean JM, Gunn AJ, Wassink G, George S, Bennet L. Endogenous alpha2-adrenergic receptor-mediated neuroprotection after severe hypoxia in preterm fetal sheep. Neuroscience 2006; 142:615-28. [PMID: 16952424 DOI: 10.1016/j.neuroscience.2006.06.066] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2006] [Revised: 06/20/2006] [Accepted: 06/21/2006] [Indexed: 11/28/2022]
Abstract
Central alpha-adrenergic receptor activity is important for fetal adaptation to hypoxia before birth. It is unclear whether it is also important during recovery. We therefore tested the hypothesis that an infusion of the specific alpha(2)-adrenergic receptor antagonist idazoxan (1 mg/kg/h i.v.) from 15 min to 4 h after profound hypoxia induced by 25 min umbilical cord occlusion in fetal sheep at 70% of gestation (equivalent to the 28-32 weeks in humans) would increase neural injury. After 3 days' recovery, idazoxan infusion was associated with a significant increase in neuronal loss in the hippocampus (P<0.05), expression of cleaved caspase-3 (P<0.05), and numbers of activated microglia (P<0.05). There was no significant effect on other neuronal regions or on loss of O4-positive premyelinating oligodendrocytes in the subcortical white matter. Idazoxan was associated with an increase in evolving epileptiform electroencephalographic (EEG) transient activity after occlusion (difference at peak 2.5+/-1.0 vs. 11.7+/-4.7 counts/min, P<0.05) and significantly reduced average spectral edge frequency, but not EEG intensity, from 54 until 72 h after occlusion (P<0.05). Hippocampal neuronal loss was correlated with total numbers of epileptiform transients during idazoxan infusion (P<0.01; r(2)=0.7). In conclusion, endogenous inhibitory alpha(2)-adrenergic receptor activation after severe hypoxia appears to significantly limit evolving hippocampal damage in the immature brain.
Collapse
Affiliation(s)
- J M Dean
- Department of Physiology, Faculty of Medicine and Health Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | | | | | | | | |
Collapse
|
19
|
Fujiki M, Kobayashi H, Inoue R, Goda M. Electrical preconditioning attenuates progressive necrosis and cavitation following spinal cord injury. J Neurotrauma 2004; 21:459-70. [PMID: 15115595 DOI: 10.1089/089771504323004601] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This study evaluates the influence of preconditioning and subsequent electrical stimulation on the formation of primary and secondary lesions following spinal cord injury in rats. The dorsal surface of the spinal cord at the T7 level was stimulated 24 h before right-side hemisection (500 Hz, 10 pulses/train, at an inter-train interval of 10 sec for 2 h). Stimulation was again administered immediately after injury and then every 24 h for 7 days. Preconditioning electrical stimulation of the spinal cord activated reactive astrocytes, then significantly attenuated edema, progressive necrosis, and cavitation, especially in the secondary cavity lesions (24 h, 1 week, and 3 weeks post-injury). Upregulation of glial fibrillary acidic protein (GFAP) and vimentin immunoreactivity, a measure of reactive astrocytic response, were increased at 1 week after injury in the rats treated with electrical stimulation. These results suggest that preconditioning with electrical stimulation prevents the formation of secondary lesions after spinal cord injury. This beneficial effect may be related to the ability of electrical stimulation to attenuate trauma-induced cellular cascades.
Collapse
Affiliation(s)
- Minoru Fujiki
- Department of Neurosurgery, School of Medicine, Oita University, Oita, Japan.
| | | | | | | |
Collapse
|
20
|
Galea E, Heneka MT, Dello Russo C, Feinstein DL. Intrinsic regulation of brain inflammatory responses. Cell Mol Neurobiol 2004; 23:625-35. [PMID: 14514020 DOI: 10.1023/a:1025084415833] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
It is now well accepted that inflammatory responses in brain contribute to the genesis and evolution of damage in neurological diseases, trauma, and infection. Inflammatory mediators including cytokines, cell adhesion molecules, and reactive oxygen species including NO are detected in human brain and its animal models, and interventions that reduce levels or expression of these agents provide therapeutic benefit in many cases. Although in some cases, the causes of central inflammatory responses are clear--for example those due to viral infection in AIDS dementia, or those due to the secretion of proinflammatory substances by activated lymphocytes in multiple sclerosis--in other conditions the factors that allow the initiation of brain inflammation are not well understood; nor is it well known why brain inflammatory activation is not as well restricted as it is in the periphery. The concept is emerging that perturbation of endogenous regulatory mechanisms could be an important factor for initiation, maintenance, and lack of resolution of brain inflammation. Conversely, activation of intrinsic regulatory neuronal pathways could provide protection in neuroinflammatory conditions. This concept is the extension of the principle of "central neurogenic neuroprotection" formulated by Donald Reis and colleagues, which contends the existence of neuronal circuits that protect the brain against the damage initiated by excitotoxic injury. In this paper we will review work initiated in the Reis laboratory establishing that activation of endogenous neural circuits can exert anti-inflammatory actions in brain, present data suggesting that these effects could be mediated by noradrenaline, and summarize recent studies suggesting that loss of noradrenergic locus ceruleus neurons contributes to inflammatory activation in Alzheimer's disease.
Collapse
Affiliation(s)
- Elena Galea
- Department of Anesthesiology, University of Illinois, Chicago, Illinois, USA
| | | | | | | |
Collapse
|
21
|
Abstract
1. Stimulation of the rostral-ventromedial pole of the cerebellar fastigial nucleus exerts powerful effects on systemic and cerebral circulation. 2. Excitation of fibers passing through the fastigial nucleus evokes sympathoactivation and increases in arterial pressure. 3. Increase in cerebral blood flow evoked by excitation of fibers passing through the FN is mediated by intrinsic brain mechanisms independently of metabolism. 4. Excitation of the fastigial nucleus neurons in contrast decreases arterial pressure and cerebral blood flow. The latter probably is secondary to the suppression of brain metabolism. 5. Excitation of the fastigial nucleus neurons significantly decreases damaging effects of focal and global ischemia on the brain. 6. The fastigial nucleus-evoked neuroprotection can be conditioned: 1-h stimulation protects the brain for up to 3 weeks. 7. Other brain structures such as subthalamic cerebrovasodilator area and dorsal periaqueductal gray matter also produce long-lasting brain salvage when stimulated. 8. More than one mechanism may account for neurogenic neuroprotection. 9. Early neuroprotection, which develops immediately after the stimulation, involves opening of potassium channels. 10. Delayed long-lasting neuroprotection may involve changes in genes expression resulting in suppression of inflammatory reaction and apoptotic cascade. 11. It is conceivable that intrinsic neuroprotective system exists within the brain, which renders the brain more tolerant to adverse stimuli when activated. 12. Knowledge of the mechanisms of neurogenic neuroprotection will allow developing new neuroprotective approaches.
Collapse
Affiliation(s)
- Eugene V Golanov
- Department of Neurosurgery, University of Mississippi Mediacl Center, 2500 North State Street, Jackson, Mississippi 39216, USA.
| | | |
Collapse
|
22
|
Wang M, Urenjak J, Fedele E, Obrenovitch TP. Effects of phosphodiesterase inhibition on cortical spreading depression and associated changes in extracellular cyclic GMP. Biochem Pharmacol 2004; 67:1619-27. [PMID: 15041479 DOI: 10.1016/j.bcp.2003.12.029] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2003] [Accepted: 12/22/2003] [Indexed: 10/26/2022]
Abstract
Cortical spreading depression (CSD) is a temporary disruption of local ionic homeostasis that propagates slowly across the cerebral cortex, and may contribute to the pathophysiology of stroke and migraine. Previous studies demonstrated that nitric oxide (NO) formation promotes the repolarisation phase of CSD, and this effect may be cyclic GMP (cGMP)-mediated. Here, we have examined how phosphodiesterase (PDE) inhibition, either alone or superimposed on NO synthase (NOS) inhibition, alters CSD and the associated changes in extracellular cGMP. Microdialysis probes incorporating an electrode were implanted into the frontoparietal cortex of anaesthetised rats for quantitative recording of CSD, pharmacological manipulations, and dialysate sampling for cGMP measurements. CSD was induced by cathodal electrical stimulation in the region under study by microdialysis. Extracellular cGMP increased, but only slightly, during CSD. Perfusion of either zaprinast or sildenafil through the microdialysis probe, at concentrations that inhibited both PDE5 and PDE9 (and possibly other PDE), increased significantly extracellular cGMP. Unexpectedly, these levels remained high when NOS was subsequently inhibited with N(omega)-nitro-l-arginine methyl ester hydrochloride (l-NAME, 1mM). The most interesting pharmacological effect on CSD was obtained with sildenafil. This drug altered neither CSD nor the subsequent characteristic effect of NOS inhibition, i.e. a marked widening of CSD. The fact that NOS inhibition still widened CSD in the presence of the high extracellular levels of cGMP associated with PDE inhibition, suggests that NO may promote CSD recovery, independently of cGMP formation.
Collapse
Affiliation(s)
- Minyan Wang
- Pharmacology, School of Pharmacy, University of Bradford, Bradford BD7 1DP, UK.
| | | | | | | |
Collapse
|
23
|
Fujiki M, Kobayashi H, Abe T, Kamida T. Repetitive transcranial magnetic stimulation for protection against delayed neuronal death induced by transient ischemia. J Neurosurg 2003; 99:1063-9. [PMID: 14705735 DOI: 10.3171/jns.2003.99.6.1063] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object. Data in the present study demonstrate that repetitive transcranial magnetic stimulation (rTMS) induces ischemic tolerance against delayed neuronal death (DND) of hippocampal neurons following an otherwise lethal ischemic insult.
Methods. Various regimens of rTMS were delivered to adult gerbils at various times prior to an episode of ischemia induced by transient (5-minute) bilateral common carotid artery (CCA) occlusion. The extent of DND in the CA1 region of the hippocampus was assessed quantitatively 7 days after the transient ischemic episode.
When rTMS was delivered 2 to 5 days prior to bilateral CCA occlusion, DND was substantially attenuated; delivery of rTMS 12 to 24 hours prior to occlusion induced partial tolerance. In the group of animals that had received stimulation 2 days prior to occlusion, neuron density in the CA1 sector was significantly higher (three gerbils, 210.33, 86.01% of normal) than in the group that experienced ischemia only (three gerbils, 10.66, 4.36% of normal). A similar degree of neuron sparing occurred when stimulation was delivered 3, 4, or 5 days prior to occlusion. Note that rTMS was effective when it was delivered at frequencies of 25 and 50 Hz. Stimulation at 25 Hz for 128 seconds (3200 pulses) was more effective than stimulation at 50 Hz for 64 seconds (3200 pulses) or 128 seconds (6400 pulses), however.
Conclusions. Noninvasive rTMS represents an important tool for exploring the mechanisms of ischemic tolerance and preventing ischemic neuronal damage.
Collapse
Affiliation(s)
- Minoru Fujiki
- Department of Neurosurgery, School of Medicine, Oita University, Oita, Japan.
| | | | | | | |
Collapse
|
24
|
Glickstein SB, Ilch CP, Reis DJ, Golanov EV. Stimulation of the subthalamic vasodilator area and fastigial nucleus independently protects the brain against focal ischemia. Brain Res 2001; 912:47-59. [PMID: 11520492 DOI: 10.1016/s0006-8993(01)02602-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We investigated whether stimulation of the functionally discrete subthalamic region, subthalamic cerebrovasodilator area (SVA), which increases cerebral blood flow (CBF) when excited, would, like stimulation of cerebellar fastigial nucleus (FN), produce central neurogenic neuroprotection. A 1-h electrical stimulation of SVA or FN reduced infarctions triggered by permanent occlusion of middle cerebral artery (MCA) by 48-55% in Sprague-Dawley rats and by 59% in Fisher rats. The salvaging effect of SVA stimulation, similar to FN, was long lasting and reduced the volume of infarctions placed 72 h or 10 days later by 58 and 26%, respectively, in Fisher rats. Bilateral lesioning of FN neurons by the microinjection of ibotenic acid 5 days before SVA stimulation did not affect SVA-evoked neuroprotection. Bilateral lesions of SVA neurons administered 5 days before FN stimulation had no effect on FN-induced neuroprotection but reversed the stimulus-locked increase in CBF accompanying FN stimulation. This study demonstrates that (1) excitation of neurons and/or fibers projecting through the SVA reduces ischemic infarctions as substantially as excitation of FN neurons; (2) the effects are long-lasting and not attributable to increases in cerebral blood flow, changes in blood gases or brain temperature, or rat strain; (3) the neuroprotective effects of SVA and FN stimulation are mutually independent and (4) FN-evoked cerebrovasodilation is mediated by SVA neurons. The SVA and FN are part of a neuronal system in CNS, which is distributed and, when excited, acts to protect the brain from ischemic injury.
Collapse
Affiliation(s)
- S B Glickstein
- Department of Psychiatry, Columbia Presbyterian Medical Center, New York State Psychiatric Institute, 1051 Riverside Drive, Box #42, New York, NY 10032, USA
| | | | | | | |
Collapse
|
25
|
Golanov EV, Christensen JD, Reis DJ. Role of potassium channels in the central neurogenic neuroprotection elicited by cerebellar stimulation in rat. Brain Res 1999; 842:496-500. [PMID: 10526150 DOI: 10.1016/s0006-8993(99)01871-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Electrical stimulation of the cerebellar fastigial nucleus (FN) in spontaneously hypertensive (SHR), Wistar-Kyoto (WKY) and Fisher rats reduced, by approximately 50%, the infarctions produced by occlusion of the middle cerebral artery. Blockade of ATP-dependent potassium (K-ATP) channels with glibenclamide (i.c.v.) abolished salvage only in the SHR rat. While blockade of K-ATP channels failed to abolish salvage in WKY and Fisher rats, participation of potassium channels in neurogenic neuroprotection cannot be excluded.
Collapse
Affiliation(s)
- E V Golanov
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, 411 East 69th Street, KB410, New York, NY 10021, USA.
| | | | | |
Collapse
|
26
|
Intrinsic neurons of fastigial nucleus mediate neurogenic neuroprotection against excitotoxic and ischemic neuronal injury in rat. J Neurosci 1999. [PMID: 10234042 DOI: 10.1523/jneurosci.19-10-04142.1999] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Electrical stimulation of the cerebellar fastigial nucleus (FN) elevates regional cerebral blood flow (rCBF) and arterial pressure (AP) and provides long-lasting protection against focal and global ischemic infarctions. We investigated which neuronal element in FN, perikarya or axons, mediates this central neurogenic neuroprotection and whether it also protects against excitotoxicity. In anesthetized rats, the FN was stimulated for 1 hr, and ibotenic acid (IBO) was microinjected unilaterally into the striatum. In unstimulated controls, the excitotoxic lesions averaged approximately 40 mm3. Stimulation of FN, but not dentate nucleus (DN), significantly reduced lesion volumes up to 80% when IBO was injected 15 min, 72 hr, or 10 d, but not 30 d, thereafter. In other rats, intrinsic neurons of FN or DN were destroyed by pretreatment with IBO. Five days later, the FN was stimulated, and 72 hr later, IBO was microinjected into the striatum. Lesions of FN, but not DN, abolished neuroprotection but not the elevations of rCBF and AP elicited from FN stimulation. Excitotoxic lesions of FN, but not DN, also abolished the 37% reduction in focal ischemic infarctions produced by middle cerebral artery occlusion. Excitation of intrinsic FN neurons provides long-lasting, substantial, and reversible protection of central neurons from excitotoxicity, as well as focal ischemia, whereas axons in the nucleus, probably collaterals of ramified brainstem neurons, mediate the elevations in rCBF, which do not contribute to neuroprotection. Long-lived protection against a range of injuries is an unrecognized function of FN neurons transmitted over pathways distinct from those regulating rCBF.
Collapse
|