scholarly journals Electroacupuncture-Induced Neuroprotection against Cerebral Ischemia in Rats: Role of the Dopamine D2 Receptor

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Ming-Shu Xu ◽  
Shu-Jing Zhang ◽  
Dan Zhao ◽  
Cheng-Yong Liu ◽  
Chang-Zhi Li ◽  
...  

Background. Cerebral ischemia is known to produce brain damage and related behavioural deficits, including memory deficits and motor disorders. Evidence shows that EA significantly promotes recovery of neurological function and thus improves quality of life.Objective. Evidence exists for the involvement of catecholamines in human neuroplasticity. A better understanding of dopaminergic (DAergic) modulation in this process will be important.Methods. A total of 72 adult male Sprague-Dawley (SD) rats were divided into 6 groups: normal, model, EA, spiperone group, EA + spiperone group, and pergolide. The middle cerebral artery occlusion (MCAO) model was used in all 6 groups except the normal group. A behavioural assessment was conducted at 1, 3, 5, and 7 days after MCAO. The percent of brain infarct area was also determined 7 days after MCAO. Tyrosine hydroxylase (TH) and growth-associated protein 43 (GAP-43) fluorescence double labeling was performed in the striatum.Results. In this study, we found that EA at Fengchi (GB20) acupoints resulted in marked improvements based on a behavioural assessment. Both TTC staining and GAP-43 immunofluorescence labeling results showed that EA treatment reduced ischemia injury and promoted neuroplasticity compared with the model group. The D2R-selective agonist, pergolide, showed similar results, but these results were reversed by the D2R-selective antagonist, spiperone. We also found that there were more colocalization and expression of GAP-43 and TH in the EA and pergolide groups than those in the other groups.Conclusion. These results suggest that the neuroplasticity induced by EA was mediated by D2 autoreceptors in DAergic neurons.

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Lingguang Liu ◽  
R. T. F. Cheung

Both melatonin and electroacupuncture (EA) have been suggested to be effective treatments against stroke. However, it is unknown whether a combination of these two therapies could be beneficial against transient focal cerebral ischemia. The present study investigated the effects of pretreatment of a combination of melatonin and EA in a rat model of transient middle cerebral artery occlusion (MCAO). After pretreatment of melatonin plus EA (MEA), transient MCAO was induced for 90 minutes in male Sprague-Dawley (SD) rats. The neurological deficit score, brain infarct volume, cerebral edema ratio, neuronal inflammation, and apoptosis were evaluated 24 hours after transient MCAO. The expression of related inflammatory and apoptotic mediators in the brain was also investigated. The results showed that MEA improved neurological outcome, reduced brain infarct volume, and inhibited neuronal inflammation as well as apoptosis 24 hours after transient MCAO. The beneficial effects may derive from downregulation of proinflammatory and proapoptotic mediators and upregulation of antiapoptotic mediators. Thus, these results suggest a preventive effect of pretreatment of MEA on transient focal cerebral ischemia.


2019 ◽  
Vol 77 (10) ◽  
pp. 689-695 ◽  
Author(s):  
Jairo Pinheiro da SILVA ◽  
Fermino Sanches LIZARTE NETO ◽  
Mucio Luiz de Assis CIRINO ◽  
Camila Albuquerque Melo de CARVALHO ◽  
Carlos Gilberto CARLOTTI JR ◽  
...  

ABSTRACT This study aimed to analyze the cerebellum of rats submitted to an experimental focal cerebral ischemia, by middle cerebral artery occlusion for 90 minutes, followed by reperfusion for 48 hours, associated with an alcoholism model. Methods Fifty adult Wistar rats were used, subdivided into five experimental groups: control group (C): animals submitted to anesthesia only; sham group (S): animals submitted to complete simulation of the surgical procedure; ischemic group (I): animals submitted to focal cerebral ischemia for 90 minutes followed by reperfusion for 48 hours; alcoholic group (A): animals that received daily absolute ethanol diluted 20% in water for four weeks; and, ischemic and alcoholic group (I + A): animals receiving the same treatment as group A and, after four weeks, submitted to focal cerebral ischemia for 90 minutes, followed by reperfusion for 48 hours. The cerebellum samples were collected and immunohistochemical analysis of Caspase-9 protein and serum analysis by RT-PCR of microRNAs miR-21, miR-126 and miR155 were performed. Results The expression of Caspase-9 was higher in groups I, A and I + A. In the microRNAs analyses, miR-126 was higher in groups A and I + A, miR-155 was higher in groups I and I + A. Conclusions We conclude that apoptosis occurs in the cerebellar cortex, even if it is distant from the ischemic focus, and that microRNAs 126 and 155 show a correlation with cellular apoptosis in ischemic rats and those submitted to the chronic alcohol model.


2016 ◽  
Vol 37 (2) ◽  
pp. 605-613 ◽  
Author(s):  
Sotaro Momosaki ◽  
Miwa Ito ◽  
Hiroko Yamato ◽  
Hitoshi Iimori ◽  
Hirokazu Sumiyoshi ◽  
...  

The changes in the availability of striatal dopamine transporter and dopamine D2 receptor after mild focal ischemia in rats were measured using a small animal positron emission tomography system. Mild focal ischemia was induced by 20-minute middle cerebral artery occlusion. [11C]PE2I binding to dopamine transporter was transiently increased on the ipsilateral side of the striatum at 2 days after middle cerebral artery occlusion. On day 7 and 14 after middle cerebral artery occlusion, [11C]PE2I binding levels were decreased. In contrast, [11C]raclopride binding to dopamine D2 receptor in the ipsilateral striatum had not changed at 2 days after middle cerebral artery occlusion. [11C]Raclopride binding was significantly decreased on the ischemic side of the striatum at 7 and 14 days after middle cerebral artery occlusion. Moreover, on day 1 and 2 after middle cerebral artery occlusion, significant circling behavior to the contralateral direction was induced by amphetamine challenge. This behavior disappeared at 7 days after middle cerebral artery occlusion. At 14 days, circling behavior to the ipsilateral direction (middle cerebral artery occlusion side) was significantly increased, and that to the contralateral direction also appeared again. The present study suggested that amphetamine-induced circling behavior indicated striatal dopaminergic alterations and that dopamine transporter and dopamine D2 receptor binding could be key markers for predicting motor dysfunction after mild focal ischemia.


2018 ◽  
Vol 40 (1) ◽  
pp. 214-224 ◽  
Author(s):  
Xia Liu ◽  
Toru Yamashita ◽  
Jingwei Shang ◽  
Xiaowen Shi ◽  
Ryuta Morihara ◽  
...  

The ubiquitin-proteasome system (UPS) and autophagy are two major pathways to degrade misfolded proteins that accumulate under pathological conditions. When UPS is overloaded, the degeneration pathway may switch to autophagy to remove excessive misfolded proteins. However, it is still unclear whether and how this switch occurs during cerebral ischemia. In the present study, transient middle cerebral artery occlusion (tMCAO) resulted in accelerated ubiquitin-positive protein aggregation from 0.5 h of reperfusion in mice brain after 10, 30 or 60 min of tMCAO. In contrast, significant reduction of p62 and induction of LC3-II were observed, peaking at 24 h of reperfusion after 30 and 60 min tMCAO. Western blot analyses showed an increase of BAG3 and HDAC6 at 1 or 24 h of reperfusion that was dependent on the ischemic period. In contract, BAG1 decreased at 24 h of reperfusion after 10, 30 or 60 min of tMCAO after double immunofluorescent colocalization of ubiquitin, HSP70, p62 and BAG3. These data suggest that a switch from UPS to autophagy occurred between 10 and 30 min of cerebral ischemia depending on the BAG1/BAG3 ratio and level of HDAC6.


2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Chujun Zhang ◽  
Sai Zhang ◽  
Lanxiang Wang ◽  
Soyeon Kang ◽  
Jiabao Ma ◽  
...  

Panax notoginseng saponins (PNS), the main bioactive constituents of a traditional Chinese herb Panax notoginseng, were commonly used for ischemic stroke in China. However, the associated cellular and molecular mechanisms of PNS have not been well examined. This study aimed to decipher the underlying molecular target of PNS in the treatment of cerebral ischemia. The oxygen-glucose-deprived (OGD) model of rat brain microvascular endothelial cells (BMECs) was used in this study. The alteration of gene expression in rat BMECs after PNS treatment was measured by microarray and indicated that there were 38 signaling pathways regulated by PNS. Among them, RIG-I receptor and related signaling molecules TNF receptor-associated factor 2 (Traf2) and nuclear factor-kappa B (NF-κB) were significantly suppressed by PNS, which was verified again in OGD-induced BMECs measured by FQ-PCR and western blotting and in middle cerebral artery occlusion (MCAO) rats measured by immunohistochemistry. The levels of TNF-α, IL-8, and the downstream cytokines regulated by RIG-I receptor pathway were also decreased by PNS. Meanwhile, the neurological evaluation, hematoxylin and eosin (HE) staining, and Evans blue staining were conducted to evaluate the effect of PNS in MCAO rats. Results showed PNS significantly improved functional outcome and cerebral vascular leakage. Flow cytometry showed the number of the inflammatory cells infiltrated in brain tissue was decreased in PNS treatment. Our results identified that RIG-I signaling pathway mediated anti-inflammatory properties of PNS in cerebral ischemia, which provided the novel insights of PNS application in clinics.


2009 ◽  
Vol 110 (3) ◽  
pp. 529-537 ◽  
Author(s):  
Irina Lasarzik ◽  
Uta Winkelheide ◽  
Sonja Stallmann ◽  
Christian Orth ◽  
Astrid Schneider ◽  
...  

Background Postischemic endogenous neurogenesis can be dose-dependently modulated by volatile anesthetics. The intravenous anesthetic propofol is used during operations with a risk of cerebral ischemia, such as neurosurgery, cardiac surgery, and vascular surgery. The effects of propofol on neurogenesis are unknown and, therefore, the object of this study. Methods Eighty male Sprague-Dawley rats were randomly assigned to treatment groups with propofol administration for 3 h: 36 mg x kg(-1) x h(-1) propofol with or without cerebral ischemia and 72 mg x kg(-1) x h(-1) propofol with or without cerebral ischemia. In addition, 7 rats with propofol administration for 6 h and 14 treatment-naive rats were investigated. Forebrain ischemia was induced by bilateral carotid artery occlusion and hemorrhagic hypotension. Animals received 5-bromo-2-deoxyuridine for 7 days. 5-Bromo-2-deoxyuridine-positive neurons were counted in the dentate gyrus after 9 and 28 days. Spatial learning in the Barnes maze and histopathologic damage of the hippocampus were analyzed. Results Propofol revealed no impact on basal neurogenesis. Cerebral ischemia increased the amount of new neurons. After 28 days, neurogenesis significantly increased in animals with low-dose propofol administered during cerebral ischemia compared with naive animals, whereas no significant difference was observed in animals with high-dose propofol during ischemia. Neuronal damage in the CA3 region was increased at 28 days with high-dose propofol. Postischemic deficits in spatial learning were not affected by propofol. Conclusions Independent effects of propofol are difficult to ascertain. Peri-ischemic propofol administration may exert secondary effects on neurogenesis by modulating the severity of histopathologic injury and thereby regenerative capacity of the hippocampus.


2009 ◽  
Vol 30 (5) ◽  
pp. 943-949 ◽  
Author(s):  
Jae Hwan Kim ◽  
Yong Woo Lee ◽  
Kyung Ah Park ◽  
Won Taek Lee ◽  
Jong Eun Lee

Brain edema is frequently shown after cerebral ischemia. It is an expansion of brain volume because of increasing water content in brain. It causes to increase mortality after stroke. Agmatine, formed by the decarboxylation of L-arginine by arginine decarboxylase, has been shown to be neuroprotective in trauma and ischemia models. The purpose of this study was to investigate the effect of agmatine for brain edema in ischemic brain damage and to evaluate the expression of aquaporins (AQPs). Results showed that agmatine significantly reduced brain swelling volume 22 h after 2 h middle cerebral artery occlusion in mice. Water content in brain tissue was clearly decreased 24 h after ischemic injury by agmatine treatment. Blood–brain barrier (BBB) disruption was diminished with agmatine than without. The expressions of AQPs-1 and -9 were well correlated with brain edema as water channels, were significantly decreased by agmatine treatment. It can thus be suggested that agmatine could attenuate brain edema by limitting BBB disruption and blocking the accumulation of brain water content through lessening the expression of AQP-1 after cerebral ischemia.


2001 ◽  
Vol 21 (4) ◽  
pp. 430-439 ◽  
Author(s):  
Laszlo Olah ◽  
Stefan Wecker ◽  
Mathias Hoehn

Changes in apparent diffusion coefficients (ADC) were compared with alterations of adenosine triphosphate (ATP) concentration and pH in different phases of transient focal cerebral ischemia to study the ADC threshold for breakdown of energy metabolism and tissue acidosis during ischemia and reperfusion. Male Wistar rats underwent 1 hour of middle cerebral artery occlusion without recirculation (n = 3) or with 1 hour (n = 4) or 10 hours of reperfusion (n = 5) inside the magnet, using a remotely controlled thread occlusion model. ADC maps were calculated from diffusion-weighted images and normalized to the preischemic value to obtain relative ADC maps. Hemispheric lesion volume (HLV) was determined on the last relative ADC maps at different relative ADC thresholds and was compared to the HLV measured by ATP depletion and by tissue acidosis. The HLVs, defined by ATP depletion and tissue acidosis, were 26.0% ± 10.6% and 38.1% ± 6.5% at the end of ischemia, 3.3% ± 2.4% and 4.8% ± 3.5% after 1 hour of reperfusion, and 11.2% ± 4.7% and 10.9% ± 5.2% after 10 hours of recirculation, respectively. The relative ADC thresholds for energy failure were consistently approximately 77% of the control value in the three different groups. The threshold for tissue acidosis was higher at the end of ischemia (86% of control) but was similar to the results obtained for ATP depletion after 1 hour (78% of control) and 10 hours (76% of control) of recirculation. These results indicate that the described relative ADC threshold of approximately 77% of control provides a good estimate for the breakdown of energy metabolism not only during middle cerebral artery occlusion but also at the early phase of reperfusion, when recovery of energy metabolism is expected to occur, or some hours later, when development of secondary energy failure was described.


2004 ◽  
Vol 24 (6) ◽  
pp. 668-676 ◽  
Author(s):  
Hiroharu Kataoka ◽  
Seong-Woong Kim ◽  
Nikolaus Plesnila

The contribution of leukocyte infiltration to brain damage after permanent focal cerebral ischemia and the underlying molecular mechanisms are still unclear. Therefore, the aim of this study was to establish a mouse model for the visualization of leukocytes in the cerebral microcirculation in vivo and to investigate leukocyte-endothelial interaction (LEI) after permanent middle cerebral artery occlusion (MCAO). Sham-operated 129/Sv mice showed physiologic LEI in pial venules as observed by intravital fluorescent microscopy. Permanent focal cerebral ischemia induced a significant increase of LEI predominantly in pial venules. The number of rolling and adherent leukocytes reached 36.5 ± 13.2/100 μm × min and 22.5 ± 7.9/100 μm × min, respectively at 120 minutes after MCAO ( P = 0.016 vs. control). Of note, rolling and adherent leukocytes were also observed in arterioles of ischemic animals (7.3 ± 3.0/100 μm × min rolling and 3.0 ± 3.6/100 μm × min adherent). Capillary density was not different between groups. These results demonstrate that leukocytes accumulate in the brain not only after transient but also after permanent focal cerebral ischemia and may therefore contribute to brain damage after stroke without reperfusion.


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