A Role for the Gtpase Pathway in Neuronal Damage after Cerebral Ischemia: The Impact of the DNA Array Technique on Stroke Research

2001 ◽  
pp. 3-9
Author(s):  
T. Trapp ◽  
L. Oláh ◽  
C. Tiesler ◽  
K. Maeda ◽  
K.-A. Hossmann
Keyword(s):  
Cerebral Ischemia ◽  
Neuronal Damage ◽  
Dna Array ◽  
Stroke Research ◽  
The Impact

scholarly journals Early Detection of Irreversible Cerebral Ischemia in the Rat Using Dispersion of the Magnetic Resonance Imaging Relaxation Time, T1ρ

2000 ◽  
Vol 20 (10) ◽  
pp. 1457-1466 ◽  
Author(s):  
Olli H J. Gröhn ◽  
Mikko I. Kettunen ◽  
Heidi I. Mäkelä ◽  
Markku Penttonen ◽  
Asla Pitkänen ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Relaxation Time ◽  
Cerebral Ischemia ◽  
Magnetic Resonance ◽  
Neuronal Damage ◽  
Therapeutic Window ◽  
Resonance Imaging ◽  
Mca Occlusion ◽  
Acute Cerebral Ischemia ◽  
The Impact

The impact of brain imaging on the assessment of tissue status is likely to increase with the advent of treatment methods for acute cerebral ischemia. Multimodal magnetic resonance imaging (MRI) demonstrates potential for selecting stroke therapy patients by identifying the presence of acute ischemia, delineating the perfusion defect, and excluding hemorrhage. Yet, the identification of tissue subject to reversible or irreversible ischemia has proven to be difficult. Here, the authors show that T1 relaxation time in the rotating frame, so-called T1ρ, serves as a sensitive MRI indicator of cerebral ischemia in the rat. The T1ρ prolongs within minutes after a drop in the CBF of less than 22 mL 100 g−1 min−1. Dependence of T1ρ on spin-lock amplitude, termed as T1ρ dispersion, increases by approximately 20% on middle cerebral artery (MCA) occlusion, comparable with the magnitude of diffusion reduction. The T1ρ dispersion change dynamically increases to be 38% ± 10% by the first 60 minutes of ischemia in the brain region destined to develop infarction. Following reperfusion after 45 minutes of MCA occlusion, the tissue with elevated T1ρ dispersion (yet normal diffusion) develops severe histologically verified neuronal damage; thus, the former parameter unveils an irreversible condition earlier than currently available MRI methods. The T1ρ dispersion as a novel MRI index of cerebral ischemia may be useful in determination of the therapeutic window for acute ischemic stroke.

scholarly journals SARS-CoV-2 and the Nervous System: From Clinical Features to Molecular Mechanisms

2020 ◽  
Vol 21 (15) ◽  
pp. 5475 ◽  
Author(s):  
Manuela Pennisi ◽  
Giuseppe Lanza ◽  
Luca Falzone ◽  
Francesco Fisicaro ◽  
Raffaele Ferri ◽  
...  
Keyword(s):  
Nervous System ◽  
Molecular Mechanisms ◽  
Neuronal Damage ◽  
Neurological Complications ◽  
Neurological Manifestations ◽  
Wide Range ◽  
Inflammatory State ◽  
Acute Polyneuropathy ◽  
The Central Nervous System ◽  
The Impact

Increasing evidence suggests that Severe Acute Respiratory Syndrome-coronavirus-2 (SARS-CoV-2) can also invade the central nervous system (CNS). However, findings available on its neurological manifestations and their pathogenic mechanisms have not yet been systematically addressed. A literature search on neurological complications reported in patients with COVID-19 until June 2020 produced a total of 23 studies. Overall, these papers report that patients may exhibit a wide range of neurological manifestations, including encephalopathy, encephalitis, seizures, cerebrovascular events, acute polyneuropathy, headache, hypogeusia, and hyposmia, as well as some non-specific symptoms. Whether these features can be an indirect and unspecific consequence of the pulmonary disease or a generalized inflammatory state on the CNS remains to be determined; also, they may rather reflect direct SARS-CoV-2-related neuronal damage. Hematogenous versus transsynaptic propagation, the role of the angiotensin II converting enzyme receptor-2, the spread across the blood-brain barrier, the impact of the hyperimmune response (the so-called “cytokine storm”), and the possibility of virus persistence within some CNS resident cells are still debated. The different levels and severity of neurotropism and neurovirulence in patients with COVID-19 might be explained by a combination of viral and host factors and by their interaction.

scholarly journals Circular RNA TTC3 regulates cerebral ischemia-reperfusion injury and neural stem cells by miR-372-3p/TLR4 axis in cerebral infarction

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Bo Yang ◽  
Li’e Zang ◽  
Jingwen Cui ◽  
Linlin Wei
Keyword(s):  
Stem Cells ◽  
Cerebral Ischemia ◽  
Cerebral Infarction ◽  
Neural Stem Cells ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Luciferase Reporter ◽  
Circular Rnas ◽  
Cerebral Ischemia Reperfusion ◽  
The Impact

Abstract Background Stroke serves as a prevalent cerebrovascular disorder with severe cerebral ischemia/reperfusion (CIR) injury, in which neural stem cells (NSCs) play critical roles in the recovery of cerebral function. Circular RNAs (circRNAs) have been widely found to participate in stroke and NSC modulation. However, the role of circRNA TTC3 (circTTC3) in the regulation of CIR injury and NSCs remains elusive. Here, we aimed to explore the impact of circTTC3 on CIR injury and NSCs. Methods The middle cerebral artery occlusion/repression (MCAO/R) model was established in C57BL/6J mice. The primary astrocytes were isolated from the cerebellum from C57BL/6J mice. The primary NSCs were obtained from rat embryos. The effect of circTTC3 on CIR injury and NSCs was analyzed by TTC staining, qPCR, Western blot, LDH colorimetric kits, MTT assays, Annexin V-FITC Apoptosis Detection Kit, luciferase reporter gene assays, and others in the system. Results Significantly, the expression of circTTC3 was elevated in the MCAO/R mice and oxygen and glucose deprivation (OGD)-treated astrocytes. The depletion of circTTC3 attenuated cerebral infarction, neurological score, and brain water content. The OGD treatment induced apoptosis and the levels of lactate dehydrogenase (LDH) in the astrocytes, in which circTTC3 depletion reduced this phenotype in the system. Moreover, the depletion of circTTC3 promoted the proliferation and upregulated the nestin and β-tubulin III expression in NSCs. Mechanically, circTTC3 was able to sponge miR-372-3p, and miR-372-3p can target Toll-like receptor 4 (TLR4) in NSCs. The miR-372-3p inhibitor or TLR4 overexpression could reverse circTTC3 depletion-mediated astrocyte OGD injury and NSC regulation. Conclusion Thus, we conclude that circTTC3 regulates CIR injury and NSCs by the miR-372-3p/TLR4 axis in cerebral infarction. Our finding presents new insight into the mechanism by which circTTC3 modulates CIR injury and NSC dysfunction. CircTTC3, miR-372-3p, and TLR4 may serve as potential targets for the treatment of CIR injury during stroke.

scholarly journals Effects of Propentofylline on Hypoxia—Hypoglycemia-Induced Calcium Accumulation in Gerbil Hippocampal Slices

1992 ◽  
Vol 12 (2) ◽  
pp. 301-305 ◽  
Author(s):  
Fumito Kadoya ◽  
Akira Mitani ◽  
Tatsuru Arai ◽  
Kiyoshi Kataoka
Keyword(s):  
Cerebral Ischemia ◽  
Intracellular Calcium ◽  
Neuronal Damage ◽  
Hippocampal Slices ◽  
Dependent Manner ◽  
Protective Effects ◽  
Calcium Accumulation ◽  
Xanthine Derivative ◽  
Acute Increase ◽  
Dose Dependent

The xanthine derivative propentofylline (HWA 285) has been reported to show protective effects against neuronal damage induced by cerebral ischemia. In the present study, microfluorometry was used to investigate the effect of propentofylline on the hypoxia–hypoglycemia-induced intracellular calcium accumulation in gerbil hippocampal slices. When slices were superfused with hypoxic–hypoglycemic medium that did not contain propentofylline, an acute increase in calcium accumulation was detected 75–200 s (mean latency of 123 s) after the beginning of hypoxia–hypoglycemia. When slices were superfused with hypoxic–hypoglycemic mediums that contained 10 μ M, 100 μ M, and 1 m M propentofylline, the latency of the acute increase in calcium accumulation was prolonged in all subregions of the hippocampus in a dose-dependent manner: mean latencies in field CA1 were 146, 168, and 197 s after hypoxia–hypoglycemia, respectively. This retardation in calcium accumulation may be involved in the mechanisms by which propentofylline diminishes ischemic injury.

scholarly journals Oxidative Stress Transiently Decreases the IKK Complex (IKKα, β, and γ), an Upstream Component of NF-κB Signaling, after Transient Focal Cerebral Ischemia in Mice

2005 ◽  
Vol 25 (10) ◽  
pp. 1301-1311 ◽  
Author(s):  
Yun S Song ◽  
Yong-Sun Lee ◽  
Pak H Chan
Keyword(s):  
Cerebral Ischemia ◽  
Focal Cerebral Ischemia ◽  
Nuclear Factor Κb ◽  
Nuclear Factor ◽  
Dna Array ◽  
Wild Type ◽  
Iκb Kinase ◽  
Transient Focal Cerebral Ischemia ◽  
Ikk Complex ◽  
In The Wild

Nuclear factor-κB (NF-κB) has a central role in coordinating the expression of a wide variety of genes that control cerebral ischemia. Although there has been intense research on NF-κB, its mechanisms in the ischemic brain have not been clearly elucidated. We investigated the temporal profile of NF-κB-related genes using a complementary DNA array method in wild-type mice and human copper/zinc-superoxide dismutase transgenic (SOD1 Tg) mice that had low-level reactive oxygen species (ROS) by scavenging superoxide. Our DNA array showed that IκB kinase (IKK) complex (IKKα, β, and γ) mRNA in the wild-type mice was decreased as early as 1 h after reperfusion, after 30 mins of transient focal cerebral ischemia (tFCI). In contrast, tFCI in the SOD1 Tg mice caused an increase in the IKK complex. The IKK complex protein levels were also drastically decreased at 1 h in the wild-type mice, but did not change in the SOD1 Tg mice throughout the 7 days. Electrophoretic mobility shift assay revealed activation of NF-κB DNA binding after tFCI in the wild-type mice. Nuclear factor-κB activation occurred at the same time, as did the phosphorylation and degradation of the inhibitory protein κBα. However, SOD1 prevented NF-κB activation, and phosphorylation and degradation of IκBα after tFCI. Superoxide production and ubiquitinated protein in the SOD1 Tg mice were also lower than in the wild-type mice after tFCI. These results suggest that ROS are implicated in transient downregulation of IKKα, β, and γ in cerebral ischemia.

scholarly journals A Model of Global Cerebral Ischemia in C57 BL/6 Mice

2004 ◽  
Vol 24 (2) ◽  
pp. 151-158 ◽  
Author(s):  
Ichiro Yonekura ◽  
Nobutaka Kawahara ◽  
Hirofumi Nakatomi ◽  
Kazuhide Furuya ◽  
Takaaki Kirino
Keyword(s):  
Cerebral Ischemia ◽  
Genetic Background ◽  
Neuronal Degeneration ◽  
Neuronal Damage ◽  
Neuronal Injury ◽  
Genetically Engineered ◽  
Global Cerebral Ischemia ◽  
Vessel Occlusion ◽  
Bilateral Carotid ◽  
The Mean

A reproducible model of global cerebral ischemia in mice is essential for elucidating the molecular mechanism of ischemic neuronal injury. Such a model is particularly important in the mouse because many genetically engineered mutant animals are available. In C57BL/6 and SV129/EMS mice, we evaluated a three-vessel occlusion model. Occlusion of the basilar artery with a miniature clip was followed by bilateral carotid occlusion. The mean cortical cerebral blood flow was reduced to less than 10% of the preischemic value, and the mean anoxic depolarization was attained within 1 minute. In C57BL/6 mice, there was CA1 hippocampal neuronal degeneration 4 days after ischemia. Neuronal damage depended upon ischemic duration: the surviving neuronal count was 78.5 ± 8.5% after 8-minute ischemia and 8.4 ± 12.7% after 14-minute ischemia. In SV129/EMS mice, similar neuronal degeneration was not observed after 14-minute ischemia. The global ischemia model in C57BL/6 mice showed high reproducibility and consistent neuronal injury in the CA1 sector, indicating that comparison of ischemic outcome between wild-type and mutant mice could provide meaningful data using the C57BL/6 genetic background. Strain differences in this study highlight the need for consideration of genetic background when evaluating ischemia experiments in mice.

scholarly journals Curcumin Protects Neuron against Cerebral Ischemia-Induced Inflammation through Improving PPAR-Gamma Function

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Zun-Jing Liu ◽  
Wei Liu ◽  
Lei Liu ◽  
Cheng Xiao ◽  
Yu Wang ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Neuronal Damage ◽  
Infarct Volume ◽  
Critical Role ◽  
Ischemic Injury ◽  
Ppar Gamma ◽  
Neurological Deficits ◽  
Protective Effects ◽  
Cerebral Ischemic Injury ◽  
Cerebral Ischemic

Cerebral ischemia is the most common cerebrovascular disease worldwide. Recent studies have demonstrated that curcumin had beneficial effect to attenuate cerebral ischemic injury. However, it is unclear how curcumin protects against cerebral ischemic injury. In the present study, using rat middle cerebral artery occlusion model, we found that curcumin was a potent PPARγagonist in that it upregulated PPARγexpression and PPARγ-PPRE binding activity. Administration of curcumin markedly decreased the infarct volume, improved neurological deficits, and reduced neuronal damage of rats. In addition, curcumin suppressed neuroinflammatory response by decreasing inflammatory mediators, such as IL-1β, TNF-α, PGE2, NO, COX-2, and iNOS induced by cerebral ischemia of rats. Furthermore, curcumin suppressed IκB degradation that was caused by cerebral ischemia. The present data also showed that PPARγinteracted with NF-κB-p65 and thus inhibited NF-κB activation. All the above protective effects of curcumin on cerebral ischemic injury were markedly attenuated by GW9662, an inhibitor of PPARγ. Our results as described above suggested that PPARγinduced by curcumin may play a critical role in protecting against brain injury through suppression of inflammatory response. It also highlights the potential of curcumin as a therapeutic agent against cerebral ischemia.

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