The action mechanism by which C1q/tumor necrosis factor-related protein-6 alleviates cerebral ischemia/reperfusion injury in diabetic mice

Studies have shown that C1q/tumor necrosis factor-related protein-6 (CTRP6) can alleviate renal ischemia/reperfusion injury in mice. However, its role in the brain remains poorly understood. To investigate the role of CTRP6 in cerebral ischemia/reperfusion injury associated with diabetes mellitus, a diabetes mellitus mouse model of cerebral ischemia/reperfusion injury was established by occlusion of the middle cerebral artery. To overexpress CTRP6 in the brain, an adeno-associated virus carrying CTRP6 was injected into the lateral ventricle. The result was that oxygen injury and inflammation in brain tissue were clearly attenuated, and the number of neurons was greatly reduced. In vitro experiments showed that CTRP6 knockout exacerbated oxidative damage, inflammatory reaction, and apoptosis in cerebral cortical neurons in high glucose hypoxia-simulated diabetic cerebral ischemia/reperfusion injury. CTRP6 overexpression enhanced the sirtuin-1 signaling pathway in diabetic brains after ischemia/reperfusion injury. To investigate the mechanism underlying these effects, we examined mice with depletion of brain tissue-specific sirtuin-1. CTRP6-like protection was achieved by activating the sirtuin-1 signaling pathway. Taken together, these results indicate that CTRP6 likely attenuates cerebral ischemia/reperfusion injury through activation of the sirtuin-1 signaling pathway.

Selective brain hypothermia-induced neuroprotection against focal cerebral ischemia/reperfusion injury is associated with Fis1 inhibition

Selective brain hypothermia is considered an effective treatment for neuronal injury after stroke,and avoids the complications of general hypothermia.However,the mechanisms by which selective brain hypothermia affects mitochondrial fission remain unknown.In this study,we investigated the effect of selective brain hypothermia on the expression of fission 1 (Fis1) protein,a key factor in the mitochondrial fission system,during focal cerebral ischemia/reperfusion injury.Sprague-Dawley rats were divided into four groups.In the sham group,the carotid arteries were exposed only.In the other three groups,middle cerebral artery occlusion was performed using the intraluminal filament technique.After 2 hours of occlusion,the filament was slowly removed to allow blood reperfusion in the ischemia/reperfusion group.Saline,at 4℃ and 37℃,were perfused through the carotid artery in the hypothermia and normothermia groups,respectively,followed by restoration of blood flow.Neurological function was assessed with the Zea Longa 5-point scoring method.Cerebral infarct volume was assessed by 2,3,5-triphenyltetrazolium chloride staining,and apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining.Fis1 and cytosolic cytochrome c levels were assessed by western blot assay.Fis1 mRNA expression was assessed by quantitative reverse transcription-polymerase chain reaction.Mitochondrial ultrastructure was evaluated by transmission electron microscopy.Compared with the sham group,apoptosis,Fis1 protein and mRNA expression and cytosolic cytochrome c levels in the cortical ischemic penumbra and cerebral infarct volume were increased after reperfusion in the other three groups.These changes caused by cerebral ischemia/reperfusion were inhibited in the hypothermia group compared with the normothermia group.These findings show that selective brain hypothermia inhibits Fis1 expression and reduces apoptosis,thereby ameliorating focal cerebral ischemia/reperfusion injury in rats.Experiments were authorized by the Ethics Committee of Qingdao Municipal Hospital of China (approval No.2019008).

Expression of Bcl-2 and NF-κB in brain tissue after acute renal ischemia-reperfusion in rats

Objective:To investigate the effect of acute renal ischemia reperfusion on brain tissue.Methods:Fourty eight rats were randomly divided into four groups(n=12):sham operation group,30 min ischemia 60 min reperfusion group,60 min ischemia 60 min reperfusion group,and120 min ischemia 60 min reperfusion group.The brain tissues were taken after the experiment.TUNEL assay was used to detect the brain cell apoptosis,and western blot was used to detect the expression of apoptosis-related proteins and inflammatory factors.Results:Renal ischemiareperiusion induced apoptosis of brain tissues,and the apoptosis increased with prolongation of ischemia time.The detection at the molecular level showed decreased Bcl-2 expression,increased Bax expression,upreguiated expression of NF- κB and its downstream factor COX-2/PGE2.Conclusions:Acute renal ischemia-reperfusion can cause brain tissue damage,manifested as induced brain tissues apoptosis and inflammation activation.

Puerarin protects brain tissue against cerebral ischemia/reperfusion injury by inhibiting the inflammatory response

Puerarin, a traditional Chinese medicine, exerts a powerful neuroprotective effect in cerebral ischemia/reperfusion injury, but its mechanism is unknown. Here, we established rat models of middle cerebral artery ischemia/reperfusion injury using the suture method. Puerarin （100 mg/kg） was administered intraperitoneally 30 minutes before middle cerebral artery occlusion and 8 hours after reperfusion. Twenty-four hours after reperfusion, we found that puerarin significantly improved neurological deficit, reduced infarct size and brain water content, and notably diminished the expression of Toll-like receptor-4, myeloid differentiation factor 88, nuclear factor kappa B and tumor necrosis factor-α in the ischemic region. These data indicate that puerarin exerts an anti-inflammatory protective effect on brain tissue with ischemia/reperfusion damage by downregulating the expression of multiple inflammatory factors.

Electroacupuncture reduces injury to the blood-brain barrier following cerebral ischemia/reperfusion injury

This study used electroacupuncture at Renzhong （DU26） and Baihui （DU20） in a rat model of cerebral ischemia/reperfusion injury. Neurological deficit scores, western blotting, and reverse transcription-PCR results demonstrated that electroacupuncture markedly reduced neurological deficits, decreased corpus striatum aquaporin-4 protein and mRNA expression, and relieved damage to the blood-brain barrier in a rat model of cerebral ischemia/reperfusion injury. These results suggest that electroacupuncture most likely protects the blood-brain barrier by regulating aquaporin-4 expression following cerebral ischemia/reperfusion injury.

Effects of “Nourishing Liver and Kidney” Acupuncture Therapy on Expression of Brain Derived Neurotrophic Factor and Synaptophysin after Cerebral Ischemia Reperfusion in Rats

The aim of the present study was to investigate the effect of ＂nourishing liver and kidney＂ acupuncture therapy on motor and cognitive deficits,and the underlying mechanism following cerebral ischemia-reperfusion（I/R） via increasing the expression of brain derived neurotrophic factor（BDNF） and synaptophysin（SYN） in the hippocampus.Healthy adult male SD rats were randomly divided into sham operation group（n=51）,model group（n=51）,acupuncture group（n=51） and acupuncture control group（n=51）.The middle cerebral I/R model was established.Acupunctures were performed in the acupuncture group and acupuncture control group at acupoints of Taixi（K103）,Taichong（ST09） of both sides,for 30 min once daily every morning.The animals in the sham operation group and model group were conventionally fed in the cage,without any intervention therapy.The rats of each group were assessed with modified neurological severity scores（m NSS）.The expression of BDNF and SYN in the hippocampus was detected by immunohistochemical SP method and the synaptic structure in hippocampus area was assessed morphologically and quantitatively at the 3rd,7th and 14 th day.The Morris water Maze（MWM） test was used to evaluate the rats＇ learning and memory abilities on the 15 th day after acupuncture.The animals in the acupuncture control group and sham operation group presented no neurological deficit.In the acupuncture group,the nerve functional recovery was significantly better than that in the model group at the 7th and 14 th day after modeling.The average MWM escape latency in the acupuncture group was shorter than that in the model group at the 3rd,4th and 5th day.The number of crossings of the platform quadrant in the acupuncture group was significantly more than that in the model group.At the each time point,the expression levels of BDNF and SYN in the hippocampal regions increased significantly in the model group as compared with the sham operation group and the acupuncture control group.In the acupuncture group,the expression levels of BDNF at the 7th and 14 th day increased more significantly than those in the model group.In the acupuncture group,the expression levels of SYN at the each time point increased more significantly than those in the model group.The post-synaptic density（PSD） was significantly increased and the synapse cleft width was narrowed in the acupuncture group as compared with other groups.The synaptic curvatures were improved obviously in the acupuncture group in contrast to the model group.It was concluded that the ＂nourishing liver and kidney＂ acupuncture therapy has positive effects on behavioral recovery,as well as learning and memory abilities,probably by promoting the expression of BDNF and SYN,and synaptic structure reconstruction in the ipsilateral hippocampus after I/R in rats.The ＂nourishing liver and kidney＂ acupuncture therapy can promote the functional recovery in rats after cerebral ischemia injury.

Matrix metalloproteinase-9 expression and blood brain barrier permeability in the rat brain after cerebral ischemia/reperfusion injury

BACKGROUND： The integrity of the blood brain barrier （BBB） plays an important role in the patho-physiological process of cerebral ischemia/reperfusion injury. It has been recently observed that metalloproteinase-9 （MMP-9） is closely related to cerebral ischemia/reperfusion injury OBJECTIVE： This study was designed to observe MMP-9 expression in the rat brain after cerebral ischemia/reperfusion injury and to investigate its correlation to BBB permeability. DESIGN, TIME AND SETTING： This study, a randomized controlled animal experiment, was performed at the Institute of Neurobiology, Central South University between September 2005 and March 2006. MATERIALS： Ninety healthy male SD rats, aged 3-4 months, weighing 200-280 g, were used in the present study. Rabbit anti-rat MMP-9 polyclonal antibody （Boster, Wuhan, China） and Evans blue （Sigma, USA） were also used. METHODS： All rats were randomly divided into 9 groups with 10 rats in each group： normal control group, sham-operated group, and ischemia for 2 hours followed by reperfusion for 3, 6, 12 hours, 1, 2, 4 and 7 days groups. In the ischemia/reperfusion groups, rats were subjected to ischemia/reperfusion injury by suture occlusion of the right middle cerebral artery. In the sham-operated group, rats were merely subjected to vessel dissociation. In the normal control group, rats were not modeled. MAIN OUTCOME MEASURES： BBB permeability was assessed by determining the level of effusion of Evans blue. MMP-9 expression was detected by an immunohistochemical method. RESULTS： All 90 rats were included in the final analysis. BBB permeability alteration was closely correlated to ischemia/reperfusion time. BBB permeability began to increase at ischemia/reperfusion for 3 hours, then it gradually reached a peak level at ischemia/reperfusion for 1 day, and thereafter it gradually decreased. MMP-9 expression began to increase at ischemia/reperfusion for 3 hours, then gradually reached its peak level 2 days after perfusion, and thereafter it gradually decreased. CONCLUSION： MMP-9 expression increases in rat brain tissue after focal cerebral ischemia/reperfusion injury, which correlates with increased permeability of the BBB.

The role of glycogen synthase kinase 3 beta in brain injury induced by myocardial ischemia/reperfusion injury in a rat model of diabetes mellitus

Myocardial ischemia/reperfusion injury can lead to severe brain injury.Glycogen synthase kinase 3 beta is known to be involved in myocardial ischemia/reperfusion injury and diabetes mellitus.However,the precise role of glycogen synthase kinase 3 beta in myocardial ischemia/reperfusion injury-induced brain injury is unclear.In this study,we observed the effects of glycogen synthase kinase 3 beta on brain injury induced by myocardial ischemia/reperfusion injury in diabetic rats.Rat models of diabetes mellitus were generated via intraperitoneal injection of streptozotocin.Models of myocardial ischemia/reperfusion injury were generated by occluding the anterior descending branch of the left coronary artery.Post-conditioning comprised three cycles of ischemia/reperfusion.Immunohistochemical staining and western blot assays demonstrated that after 48 hours of reperfusion,the structure of the brain was seriously damaged in the experimental rats compared with normal controls.Expression of Bax,interleukin-6,interleukin-8,terminal deoxynucleotidyl transferase d UTP nick end labeling,and cleaved caspase-3 in the brain was significantly increased,while expression of Bcl-2,interleukin-10,and phospho-glycogen synthase kinase 3 beta was decreased.Diabetes mellitus can aggravate inflammatory reactions and apoptosis.Ischemic post-conditioning with glycogen synthase kinase 3 beta inhibitor lithium chloride can effectively reverse these changes.Our results showed that myocardial ischemic post-conditioning attenuated myocardial ischemia/reperfusion injury-induced brain injury by activating glycogen synthase kinase 3 beta.According to these results,glycogen synthase kinase 3 beta appears to be an important factor in brain injury induced by myocardial ischemia/reperfusion injury.

Expression of netrin-1 and its receptors, deleted in colorectal cancer and uncoordinated locomotion-5 homolog B, in rat brain following focal cerebral ischemia reperfusion injury

Netrin-1 is currently one of the most highly studied axon guidance factors. Netrin-1 is widely expressed in the embryonic central nervous system, and together with the deleted in colorectal cancer and uncoordinated locomotion-5 homolog B receptors, netrin-1 plays a guiding role in the construction of neural conduction pathways and the directional migration of neuronal cells. In this study, we established a rat middle cerebral artery ischemia reperfusion model using the intraluminal thread technique. Immunofluorescence microscopy showed that the expression of netrin-1 and deleted in colorectal cancer in the ischemic penumbra was upregulated at 1 day after reperfusion, reached a peak at 14 days, and decreased at 21 days. There was no obvious change in the expression of uncoordinated locomotion-5 homolog B during this time period. Double immunofluorescence labeling revealed that netrin-1 was expressed in neuronal cells and around small vessels, but not in astrocytes and microglia, while deleted in colorectal cancer was localized in the cell membranes and protrusions of neurons and astrocytes. Our experimental findings indicate that netrin-1 may be involved in post-ischemic repair and neuronal protection via deleted in colorectal cancer receptors.

Pretreatment with Danhong injection protects the brain against ischemia-reperfusion injury

Danhong injection （DHI）, a Chinese Materia Medica standardized product extracted from Radix Salviae miltiorrhizae and Flos Carthami tinctorii, is widely used in China for treating acute isch-emic stroke. In the present study, we explored the neuroprotective efficacy of DHI in a rat model of temporary middle cerebral artery ocdusion, and evaluated the potential mechanisms under-lying its effects. Pretreatment with DHI （0.9 and 1.8 mL/kg） resulted in a significantly smaller infarct volume and better neurological scores than pretreatment with saline. Furthermore, DHI significantly reduced the permeability of the blood-brain barrier, increased occludin protein expression and decreased neutrophil infiltration, as well as profoundly suppressing the upreg-ulation of matrix metallopeptidase-9 expression seen in rats that had received vehicle. Matrix metallopeptidase-2 expression was not affected by ischemia or DHI. Moreover, DHI （1.8 mL/kg） administered 3 hours after the onset of ischemia also improved neurological scores and reduced infarct size. Our results indicate that the neuroprotective efficacy of DHI in a rat model of cerebral ischemia-reperfusion injury is mediated by a protective effect on the blood-brain barrier and the reversal of neutrophil infiltration.

Effects of Chuanxiongqin hydrochloride on increasing the fluidity of brain cell membrane and scavenging free radicals in model rats with ischemia/reperfusion injury

BACKGROUND: The fluidity of cell membrane can be affected by various factors. Many experiments have confirmed that the ischemia/reperfusion of organic tissue can increase the contents of free radicals, which lead to high rigidity and low fluidity of cell membrane, and the conditions can be changed by Chuanxiongqin. OBJECTIVE: To observe the effect and mechanism of Chuanxiongqin hydrochloride on the fluidity of brain cell membrane in rat models of ischemia/reperfusion. DESIGN: A completely randomized controlled animal trial. SETTINGS: Institute of Brain Sciences; Department of Physiology, Medical College, Datong University. MATERIALS: Twenty male grade Ⅰ Wistar rats of 170-220 g were randomly divided into model group (n =10) and control group (n =10). Chuanxiongqin hydrochloride (molecular mass was 172.2) was purchased from the National Institute for the Control of Pharmaceutical and Biological Products (batch number: 0817-9803); Spin labelers: 5-doxyl-stearlic acid methylester (5DS), 16-doxyl-stearlic acid methylester (16DS), xanthine, xanthine oxidase (XOD) and 5,5-dimeth-1-pyrroline- N-oxide (DMPO) from Sigma Company; Bruker ESP 300 electron paramagnetic resonance (EPR) spectrometer by Bruker Company (Germany). METHODS: The experiments were carried out in the State Key Laboratory of Natural and Biomimetic Drugs, Peking University from June 2001 to July 2002. In the model group, rats were made into models of cerebral ischemia by 30-minute ligation and 2-hour reperfusion of common carotid arteries; The rats in the control group were not made into models. The order parameter (S) and rotational correlation time (τc) were detected with the ESR spectrometer by means of spin labeling. The greater the S and τc, the smaller the fluidity. Meanwhile, the clearance rate of free radicals was detected with ESR spin trapping. The measurement data were compared using the t test. MAIN OUTCOME MEASURES: The S, τc and clearance rates of O2 · and OH· free radicals were compared between the model group and control group. RESULTS: The S and τc in the model group [0.738 4±0.003 5; (8.472±0.027)×10-10 s/circle] were obviously different from those in the control group [0.683 9±0.008 3; (7.945±0.082)×10-10 s/circle, t =5.731, 5.918, P < 0.05], which suggested that ischemia/reperfusion injury decreased the fluidity of brain cell membrane. After adding Chuanxiongqin hydrochloride, there were no obvious differences between the model group [0.688 5±0.030 5; (7.886±0.341)×10-10 s/circle] and control group (P > 0.05), indicating that Chuanxiongqin hydrochloride could recover the fluidity of brain cell membrane after ischemia/reperfusion injury close to the level in the normal control group. Chuanxiongqin hydrochloride could directly scavenge the O2 · and OH· free radicals, and the maximal clearance rates were 83.92% and 44.99% respectively. CONCLUSION: Chuanxiongqin hydrochloride increases the fluidity of membrane of ischemia-injured brain cell by scavenging both O2 ·and OH· free radicals.

Electroacupuncture stimulation of the brachial plexus trunk on the healthy side promotes brain-derived neurotrophic factor mRNA expression in the ischemic cerebral cortex of a rat model of cerebral ischemia/reperfusion injury

A rat model of cerebral ischemia/reperfusion was established by suture occlusion of the left middle cerebral artery. In situ hybridization results showed that the number of brain-derived neurotrophic factor mRNA-positive cells in the ischemic rat cerebral cortex increased after cerebral ischemia/ reperfusion injury. Low frequency continuous wave electroacupuncture （frequency 2-6 Hz, current intensity 2 mA） stimulation of the brachial plexus trunk on the healthy （right） side increased the number of brain-derived neurotrophic factor mRNA-positive cells in the ischemic cerebral cortex 14 days after cerebral ischemia/reperfusion injury. At the same time, electroacupuncture stimulation of the healthy brachial plexus truck significantly decreased neurological function scores and alleviated neurological function deficits. These findings suggest that electroacupuncture stimulation of the brachial plexus trunk on the healthy （right） side can greatly increase brain-derived neurotrophic factor mRNA expression and improve neurological function.

Does closure of acid-sensing ion channels reduce ischemia/reperfusion injury in the rat brain?

Acidosis is a common characteristic of brain damage. Because studies have shown that permeable Ca2＋-acid-sensing ion channels can mediate the toxic effects of calcium ions, they have become new targets against pain and various intracranial diseases. However, the mechanism associated with expression of these channels remains unclear. This study sought to observe the expression characteristics of permeable Ca2＋-acid-sensing ion channels during different reperfusion inflows in rats after cerebral ischemia. The rat models were randomly divided into three groups： adaptive ischemia/reperfusion group, one-time ischemia/reperfusion group, and severe cerebral ischemic injury group. Western blot assays and immunofluorescence staining results exhibited that when compared with the one-time ischemia/reperfusion group, acid-sensing ion channel 3 and Bcl-x/I expression decreased in the adaptive ischemia/reperfusion group. Calmodulin expression was lowest in the adaptive ischemia/reperfusion group. Following adaptive reperfusion, common carotid artery flow was close to normal, and the pH value improved. Results verified that adaptive reperfusion following cerebral ischemia can suppress acid-sensing ion channel 3 expression, significantly reduce Ca2＋ influx, inhibit calcium overload, and diminish Ca2＋ toxicity. The effects of adaptive ischemia/reperfusion on suppressing cell apoptosis and relieving brain damage were better than that of one-time ischemia/reperfusion.

Preventive administration of cromakalim reduces aquaporin-4 expression and blood-brain barrier permeability in a rat model of cerebral ischemia/reperfusion injury

Cromakalim,an adenosine triphosphate-sensitive potassium channel opener,exhibits protective effects on cerebral ischemia/reperfusion injury.However,there is controversy as to whether this effect is associated with aquaporin-4 and blood-brain barrier permeability.Immunohistochemistry results show that preventive administration of cromakalim decreased aquaporin-4 and IgG protein expression in rats with ischemia/reperfusion injury;it also reduced blood-brain barrier permeability,and alleviated brain edema,ultimately providing neuroprotection.

Effects of Panax Notoginseng Saponin on the Expression of Vascular Endothelial Growth Factor after the Brain Ischemia-reperfusion Injury in Rats

Objective： To observe effects of Panax Notoginseng Saponin （PSN） on the expression of Vascular Endothelial Growth Factor （VEGF） after the brain ischemia-reperfusion injury in rats. Methods： 48 SD rats had been randomly divided into 4 groups： the sham operation group, the model group, Panax Notoginseng Saponin （PNS） group and Nimodipine group （n=12） . The rats had been treated with PNS, and 7 days later the rat focal cerebral ischemia-reperfusion models had been pre- pared. Neurobehavioral scores （NBS） had been evaluated in each group, TTC staining observed; the immunohistochemistry was used to observe VEGF and mRNA expressions. Results： PNS could not only improve significantly neurobehavioral scores and decrease dramatically cerebral infarct volume, but also increase remarkably VEGF and mRNA expression levels. Conclusion： The PNS is beneficial for rehabilitation after cerebral ischemia reperfusion injury via effectively up-regulating the injured cor- tical VEGF mRNA expression concentrations, which promotes vascular reborn in the ischemic region.

Influence of ginkgolide combined with edaravone on the brain function of elderly patients with acute cerebral infarction and its preventive effect on ischemia reperfusion injury

Objective: To explore the influence of ginkgolide combined with edaravone on the brain function of elderly patients with acute cerebral infarction and its preventive effect on ischemia reperfusion injury. Methods: A total of 126 patients with acute cerebral infarction who were treated in Dazhou Central Hospital between February 2016 and May 2017 were divided into the control group (n=67) and ginkgolide group (n=59) according to different therapies. Control group received routine intravenous thrombolysis + edaravone therapy, and ginkgolide group received routine intravenous thrombolysis + edaravone + ginkgolide therapy. The differences in brain function and nerve ischemia reperfusion injury extent were compared between the two groups. Results: At T1 and T2, serum nerve function indexes NT-proBNP and NSE levels of ginkgolide group were lower than those of control group whereas BDNF levels were higher than those of control group;serum inflammatory mediators MCP-1, NF-κB, CRP and TNF-α levels were lower than those of control group;serum apoptosis molecules caspase-3 and Bax levels were lower than those of control group whereas Bcl-2 levels were higher than those of control group. Conclusion: Ginkgolide combined with edaravone therapy on the basis of intravenous thrombolysis can effectively optimize the brain function and alleviate the ischemia reperfusion injury caused by inflammatory response and apoptosisis in elderly patients with acute cerebral infarction.

Atorvastatin protects against cerebral ischemia/ reperfusion injury through anti-inflammatory and antioxidant effects

In addition to its lipid-lowering effect, atorvastatin exerts anti-inflammatory and antioxidant effects as well. In this study, we hypothesized that atorvastatin could protect against cerebral isch-emia/reperfusion injury. The middle cerebral artery ischemia/reperfusion model was established, and atorvastatin, 6.5 mg/kg, was administered by gavage. We found that, after cerebral ischemia/ reperfusion injury, levels of the inflammation-related factors E-selectin and myeloperoxidase were upregulated, the oxidative stress-related marker malondialdehyde was increased, and super- oxide dismutase activity was decreased in the ischemic cerebral cortex. Atorvastatin pretreatment significantly inhibited these changes. Our findings indicate that atorvastatin protects against ce-rebral ischemia/reperfusion injury through anti-inflammatory and antioxidant effects.

Neuronal apoptosis in cerebral ischemia/reperfusion area following electrical stimulation of fastigial nucleus

Previous studies have indicated that electrical stimulation of the cerebellar fastigial nucleus in rats may reduce brain infarct size, increase the expression of Ku70 in cerebral ischemia/ reperfusion area, and decrease the number of apoptotic neurons. However, the anti-apoptotic mechanism of Ku70 remains unclear. In this study, fastigial nucleus stimulation was given to rats 24, 48, and 72 hours before cerebral ischemia/reperfusion injury. Results from the electrical stim- ulation group revealed that rats exhibited a reduction in brain infarct size, a significant increase in the expression of KuT0 in cerebral ischemia/reperfusion regions, and a decreased number of terminal deoxynucleotidyl transferase dUTP nick end labeling （TUNEL）-positive cells. Double immunofluorescence staining revealed no co-localization of Ku70 with TUNEL-positive cells. However, Ku70 partly co-localized with Bax protein in the cytoplasm of rats with cerebral ischemia/reperfusion injury. These findings suggest an involvement of Ku70 with Bax in the cy- toplasm of rats exposed to electrical stimulation of the cerebellar fastigial nucleus, and may thus provide an understanding into the anti-apoptotic activity of KuT0 in cerebral ischemia/reperfu- sion injury.

Electroacupuncture reduces apoptotic index and inhibits p38 mitogen-activated protein kinase signaling pathway in the hippocampus of rats with cerebral ischemia/reperfusion injury

Electroacupuncture attenuates cerebral hypoxia and neuronal apoptosis induced by cerebral ischemia/reperfusion injury.To further identify the involved mechanisms,we assumed that electroacupuncture used to treat cerebral ischemia/reperfusion injury was associated with the p38 mitogen-activated protein kinase（MAPK） signaling pathway.We established rat models of cerebral ischemia/reperfusion injury using the modified Zea-Longa＇s method.At 30 minutes before model establishment,p38 MAPK blocker SB20358 was injected into the left lateral ventricles.At 1.5 hours after model establishment,electroacupuncture was administered at acupoints of Chize（LU5）,Hegu（LI4）,Zusanli（ST36）,and Sanyinjiao（SP6） for 20 minutes in the affected side.Results showed that the combination of EA and SB20358 injection significantly decreased neurologic impairment scores,but no significant differences were determined among different interventional groups.Hematoxylin-eosin staining also showed reduced brain tissue injuries.Compared with the SB20358 group,the cells were regularly arranged,the structures were complete,and the number of viable neurons was higher in the SB20358 ＋ electroacupuncture group.Terminal deoxynucleotidyl transferase（Td T）-mediated d UTP nick-end labeling assay showed a decreased apoptotic index in each group,with a significant decrease in the SB20358 ＋ electroacupuncture group.Immunohistochemistry revealed reduced phosphorylated p38 expression at 3 days in the electroacupuncture group and SB20358 ＋ electroacupuncture group compared with the ischemia/reperfusion group.There was no significant difference in phosphorylated p38 expression between the ischemia/reperfusion group and SB20358 group.These findings confirmed that the electroacupuncture effects on mitigating cerebral ischemia/reperfusion injury are possibly associated with the p38 MAPK signaling pathway.A time period of 3 days could promote the repair of ischemic cerebral nerves.

Anti-oxidant effect of picroside II in a rat model of cerebral ischemia/reperfusion injury

Picroside II,the major active component of picroside,has been shown to induce PC12 cell axonal growth and relieve free radical damage.In vivo experiments have demonstrated that picroside II can improve neurological function in rats with cerebral ischemia/reperfusion injuries.In the present in vivo study,enzyme-linked immunosorbent assay and immunohistochemistry revealed that picroside II increased superoxide dismutase content and reduced inducible nitric oxide synthase content in the ischemic hemisphere.The effects of picroside II were similar to those of salvianic acid A sodium,an active control drug.These results indicate that picroside II exerts a neuroprotective effect,possibly by downregulating inducible nitric oxide synthase expression,increasing superoxide dismutase activity,and inhibiting neuronal apoptosis.