Variability of neuronal damage and proportion of activities of NO synthase isoforms during cerebral ischemia/reperfusion in rats

2007 ◽  
Vol 144 (5) ◽  
pp. 657-660
Author(s):  
V. I. Petrov ◽  
V. B. Pisarev ◽  
E. A. Ponomarev ◽  
V. V. Novochadov ◽  
N. N. Strepetov
Keyword(s):  
Cerebral Ischemia ◽  
Neuronal Damage ◽  
Ischemia Reperfusion ◽  
No Synthase ◽  
Cerebral Ischemia Reperfusion

scholarly journals MicroRNA-27a-3p Relives Inflammation and Neurologic Impairment after Cerebral Ischemia Reperfusion via Inhibiting LITAF and the TLR4/NF-κB Pathway

2020 ◽  
Author(s):  
Jing Luo ◽  
Junjie Li ◽  
Li Xiong ◽  
Linna Fan ◽  
Lijia Peng ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Neuronal Damage ◽  
Expression Profiles ◽  
Ischemia Reperfusion ◽  
Underlying Mechanism ◽  
Neurologic Deficit ◽  
Luciferase Assay ◽  
Ischemic Reperfusion ◽  
Post Surgery ◽  
Cerebral Ischemia Reperfusion

Abstract Background: Cerebral ischemia reperfusion (CIR) affects microRNA (miR) expression and causes substantial inflammation. Here, we investigated the influence and underlying mechanism of miR-27-3p in rats with CIR.Methods: Cerebral ischemia reperfusion was built by tMCAO. Rats were randomly divided into Sham group, brain ischemic reperfusion (IR) group, brain ischemic reperfusion transfected with NC group, brain ischemic reperfusion transfected with miR-27a-3p mimic group, brain ischemic reperfusion transfected with miR-27a-3p inhibitor group and brain ischemic reperfusion transfected with miR-27a-3p mimic and Litaf mimic group. The relationship between miR-27a-3p and Litaf was verified via qRT-PCR and luciferase assays. The cellular distribution of Litaf was determined via double immunofluorescence. The effect of miR-27a-3p on the expression of Litaf, TLR4, NF-κB and IL-6 was evaluated using synthetic miR-27a-3p mimic and inhibitor. The level of Nissl’s body in each group was detected by Nissl’s staining. The infarct in each group was evaluated by TTC staining.Results: Firstly, BV treatment relieves cerebral infarction and decreases the levels of serum IL-1β, IL-6 and TNF-α. Through our previous study, we found key microRNA mR-27a-3p and its targeted gene Litaf might involve in the molecular mechanism of CIR. Then, the regulation between miR-27a-3p and Litaf was verified by the temporal miR-27a-3p and Litaf expression profiles and luciferase assay. Moreover, intracerebroventricular injection of the miR-27a-3p mimic significantly decreased the Litaf, TLR4, NF-κB and interleukin (IL)-6 levels and the double-labeled cell count 24 h post-surgery, whereas miR-27a-3p inhibitor reversed these effects. Furthermore, miR-27a-3p mimic could relive cerebral infarct and neurologic deficit after CIR. In addition, injection of miR-27a-3p mimic decreased neuronal damage induced by CIR.Conclusions: Increasing miR-27-3p levels protect against CIR by relieving inflammation, neuronal damage and neurologic deficit by inhibiting LITAF and the TLR4/NF-κB pathway.

scholarly journals Destructive Effects of Pyroptosis on Homeostasis of Neuron Survival Associated with the Dysfunctional BBB-Glymphatic System and Amyloid-Beta Accumulation after Cerebral Ischemia/Reperfusion in Rats

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Zhongkuan Lyu ◽  
Yuanjin Chan ◽  
Qiyue Li ◽  
Qiang Zhang ◽  
Kaili Liu ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Amyloid Beta ◽  
Neuronal Damage ◽  
Ischemia Reperfusion ◽  
Artery Occlusion ◽  
Neurological Deficits ◽  
Specific Marker ◽  
Nissl Staining ◽  
Glymphatic System ◽  
Cerebral Ischemia Reperfusion

Neuroinflammation-related amyloid-beta peptide (Aβ) accumulation after cerebral ischemia/reperfusion (I/R) accounts for cerebral I/R injuries and poststroke dementia. Recently, pyroptosis, a proinflammatory cell death, has been identified as a crucial pathological link of cerebral I/R injuries. However, whether pyroptosis acts as a trigger of Aβ accumulation after cerebral I/R has not yet been demonstrated. Blood-brain barrier (BBB) and glymphatic system mediated by aquaporin-4 (AQP-4) on astrocytic endfeet are important pathways for the clearance of Aβ in the brain, and pyroptosis especially occurring in astrocytes after cerebral I/R potentially damages BBB integrity and glymphatic function and thus influences Aβ clearance and brain homeostasis. In present study, the method of middle cerebral artery occlusion/reperfusion (MCAO/R) was used for building models of focal cerebral I/R injuries in rats. Then, we used lipopolysaccharide and glycine as the agonist and inhibitor of pyroptosis, respectively, Western blotting for detections of pyroptosis, AQP-4, and Aβ1-42 oligomers, laser confocal microscopy for observations of pyroptosis and Aβ locations, and immunohistochemical stainings of SMI 71 (a specific marker for BBB integrity)/AQP-4 and Nissl staining for evaluating, respectively, BBB-glymphatic system and neuronal damage. The results showed that pyroptosis obviously promoted the loss of BBB integrity and AQP-4 polarization, brain edema, Aβ accumulation, and the formation of Aβ1-42 oligomers and thus increased neuronal damage after cerebral I/R. However, glycine could inhibit cerebral I/R-induced pyroptosis by alleviating cytomembrane damage and downregulating expression levels of cleaved caspase-11/1, N-terminal gasdermin D, NLRP3 (nucleotide-binding domain, leucine-rich repeat containing protein 3), interleukin-6 (IL-6) and IL-1β and markedly abate above pathological changes. Our study revealed that pyroptosis is a considerable factor causing toxic Aβ accumulation, dysfunctional BBB-glymphatic system, and neurological deficits after cerebral I/R, suggesting that targeting pyroptosis is a potential strategy for the prevention of ischemic stroke sequelae including dementia.

scholarly journals N6-methyladenosine demethylases Alkbh5/Fto regulate cerebral ischemia-reperfusion injury

2020 ◽  
Vol 11 ◽  
pp. 204062232091602 ◽  
Author(s):  
Kaiwei Xu ◽  
Yunchang Mo ◽  
Dan Li ◽  
Qimin Yu ◽  
Lu Wang ◽  
...  
Keyword(s):  
Cerebral Cortex ◽  
Cerebral Ischemia ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Neuronal Damage ◽  
Ischemia Reperfusion ◽  
Neuronal Cell ◽  
Cerebral Ischemia Reperfusion ◽  
Cerebral Ischemia Reperfusion Injury

Background: Although N6-methyladenosine (m6A) plays a very important role in different biological processes, its function in the brain has not been fully explored. Thus, we investigated the roles of the RNA demethylases Alkbh5/Fto in cerebral ischemia-reperfusion injury. Methods: We used a rat model and primary neuronal cell culture to study the role of m6A and Alkbh5/Fto in the cerebral cortex ischemic penumbra after cerebral ischemia-reperfusion injury. We used Alkbh5-shRNA and Lv-Fto ( in vitro) to regulate the expression of Alkbh5/Fto to study their regulation of m6A in the cerebral cortex and to study brain function after ischemia-reperfusion injury. Results: We found that RNA m6A levels increased consecutive to the increase of Alkbh5 expression in both the cerebral cortex of rats after middle cerebral artery occlusion, and in primary neurons after oxygen deprivation/reoxygenation. In contrast, Fto expression decreased after these perturbations. Our results suggest that knocking down Alkbh5 can aggravate neuronal damage. This is due to the demethylation of Alkbh5 and Fto, which selectively demethylate the Bcl2 transcript, preventing Bcl2 transcript degradation and enhancing Bcl2 protein expression. Conclusion: Collectively, our results demonstrate that the demethylases Alkbh5/Fto co-regulate m6A demethylation, which plays a crucial role in cerebral ischemia-reperfusion injury. The results provide novel insights into potential therapeutic mechanisms for stroke.

Neuroprotective Effect of Urinary Trypsin Inhibitor against Focal Cerebral Ischemia–Reperfusion Injury in Rats

2003 ◽  
Vol 98 (2) ◽  
pp. 465-473 ◽  
Author(s):  
Toshiyuki Yano ◽  
Sakiko Anraku ◽  
Ryosuke Nakayama ◽  
Kazuo Ushijima
Keyword(s):  
Cerebral Ischemia ◽  
Reperfusion Injury ◽  
Trypsin Inhibitor ◽  
Ischemia Reperfusion Injury ◽  
Neuronal Damage ◽  
Focal Cerebral Ischemia ◽  
Ischemia Reperfusion ◽  
Saline Control ◽  
Urinary Trypsin Inhibitor ◽  
Cerebral Ischemia Reperfusion

Background Acute inflammatory reactions cause neuronal damage in cerebral ischemia-reperfusion. Urinary trypsin inhibitor (UTI), a serine protease inhibitor, is cytoprotective against ischemia-reperfusion injury in the liver, intestine, kidney, heart, and lung through its antiinflammatory activity. Neuroprotective action of UTI on transient global cerebral ischemia has been documented. This is the first study to determine whether UTI is neuroprotective against transient focal cerebral ischemia. Methods Adult male Wistar rats were randomly assigned to the following treatment groups: 0.9% saline (control, n = 9); 100,000 U/kg UTI (n = 9); and 300,000 U/kg UTI (n = 9). Treatments were performed intravenously 10 min before right middle cerebral artery occlusion for 2 h and subsequent reperfusion. Ninety-six hours after the onset of reperfusion, the motor neurologic deficit and the cerebral infarct size were evaluated. Furthermore, immunohistochemical staining for myeloperoxidase and nitrotyrosine to count infiltrating neutrophils and nitrated cells, respectively, was performed on the brain sections. Results Infarct volume in the 300,000 U/kg UTI group was smaller than in the 100,000 U/kg UTI and saline control groups (P < 0.05). Treatment with 300,000 U/kg UTI showed a trend to improve neurologic outcome but did not reach statistical significance (P = 0.0693). The significant decrease in neutrophil infiltration was observed in the ischemic hemisphere treated with 300,000 U/kg UTI compared with saline control (P < 0.05). Nitrotyrosine deposition in the ischemic hemisphere was significantly reduced in the 300,000 U/kg UTI group compared with saline control and 100,000 U/kg UTI groups (P < 0.05). Conclusions Intravenous pretreatment with 300,000 U/kg UTI reduces focal ischemia-reperfusion injury in the rat brain, potentially opening a novel therapeutic avenue for the treatment of cerebral ischemia.

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