Total Saponins of Panax notoginseng Activate Akt/mTOR Pathway and Exhibit Neuroprotection in vitro and in vivo against Ischemic Damage / 中国结合医学杂志

OBJECTIVE@#To reveal the neuroprotective effect and the underlying mechanisms of a mixture of the main components of Panax notoginseng saponins (TSPN) on cerebral ischemia-reperfusion injury and oxygen-glucose deprivation/reoxygenation (OGD/R) of cultured cortical neurons.@*METHODS@#The neuroprotective effect of TSPN was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, flow cytometry and live/dead cell assays. The morphology of dendrites was detected by immunofluorescence. Middle cerebral artery occlusion (MCAO) was developed in rats as a model of cerebral ischemia-reperfusion. The neuroprotective effect of TSPN was evaluated by neurological scoring, tail suspension test, 2,3,5-triphenyltetrazolium chloride (TTC) and Nissl stainings. Western blot analysis, immunohistochemistry and immunofluorescence were used to measure the changes in the Akt/mammalian target of rapamycin (mTOR) signaling pathway.@*RESULTS@#MTT showed that TSPN (50, 25 and 12.5 µ g/mL) protected cortical neurons after OGD/R treatment (P<0.01 or P<0.05). Flow cytometry and live/dead cell assays indicated that 25 µ g/mL TSPN decreased neuronal apoptosis (P<0.05), and immunofluorescence showed that 25 µ g/mL TSPN restored the dendritic morphology of damaged neurons (P<0.05). Moreover, 12.5 µ g/mL TSPN downregulated the expression of Beclin-1, Cleaved-caspase 3 and LC3B-II/LC3B-I, and upregulated the levels of phosphorylated (p)-Akt and p-mTOR (P<0.01 or P<0.05). In the MCAO model, 50 µ g/mL TSPN improved defective neurological behavior and reduced infarct volume (P<0.05). Moreover, the expression of Beclin-1 and LC3B in cerebral ischemic penumbra was downregulated after 50 µ g/mL TSPN treatment, whereas the p-mTOR level was upregulated (P<0.05 or P<0.01).@*CONCLUSION@#TSPN promoted neuronal survival and protected dendrite integrity after OGD/R and had a potential therapeutic effect by alleviating neurological deficits and reversing neuronal loss. TSPN promoted p-mTOR and inhibited Beclin-1 to alleviate ischemic damage, which may be the mechanism that underlies the neuroprotective activity of TSPN.

Echinacoside Alleviates Cognitive Impairment in Cerebral Ischemia Rats through α 7nAChR-Induced Autophagy / 中国结合医学杂志

OBJECTIVES@#To evaluate the effect of echinacoside (ECH) on cognitive dysfunction in post cerebral stroke model rats.@*METHODS@#The post stroke cognitive impairment rat model was created by occlusion of the transient middle cerebral artery (MCAO). The rats were randomly divided into 3 groups by a random number table: the sham group (sham operation), the MCAO group (received operation for focal cerebral ischemia), and the ECH group (received operation for focal cerebral ischemia and ECH 50 mg/kg per day), with 6 rats in each group. The infarct volume and spatial learning were evaluated by triphenyl tetrazolium chloride staining and Morris water maze. The expression of α7nAChR in the hippocampus was detected by immunohistochemistry. The contents of acetylcholine (ACh), malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), activities of choline acetyltransferase (ChAT), acetylcholinesterase (AChE), and catalase (CAT) were evaluated by enzyme linked immunosorbent assay. The neural apoptosis and autophagy were determined by TUNEL staining and LC3 staining, respectively.@*RESULTS@#ECH significantly lessened the brain infarct volume and ameliorated neurological deficit in infarct volume and water content (both P<0.01). Compared with MCAO rats, administration of ECH revealed shorter escape latency and long retention time at 7, 14 and 28 days (all P<0.01), increased the α7nAChR protein expression, ACh content, and ChAT activity, and decreased AChE activity in MCAO rats (all P<0.01). ECH significantly decreased MDA content and increased the GSH content, SOD, and CAT activities compared with MCAO rats (all P<0.05). ECH suppressed neuronal apoptosis by reducing TUNEL-positive cells and also enhanced autophagy in MCAO rats (all P<0.01).@*CONCLUSION@#ECH treatment helped improve cognitive impairment by attenuating neurological damage and enhancing autophagy in MCAO rats.

Protective effect and mechanism of Ershiwuwei Zhenzhu Pills on cerebral apoplexy rats / 中国中药杂志

To study the protective effect of Ershiwuwei Zhenzhu Pills on ischemic stroke rats. Ninety 4-weeks-old SPF male SD rats were randomly divided into 6 groups(n=15):sham operation group, model group, nimodipine group(12 mg·kg~(-1)), Ershiwuwei Zhenzhu Pills high-dose group(400 mg·kg~(-1)), Ershiwuwei Zhenzhu Pills medium-dose group(200 mg·kg~(-1)), Ershiwuwei Zhenzhu Pills low-dose group(100 mg·kg~(-1)).The permanent middle cerebral artery occlusion model(PMCAO) was established in the model group, nimodipine group, and Ershiwuwei Zhenzhu Pills groups by the improved thread plug method, while the sham operation group did not insert the thread plug.Nimodipine group and Ershiwuwei Zhenzhu Pills groups were given intragastric administration once a day for 24 days before the modeling operation, and once 1 hour before the modeling operation, while sham operation group and model group were given equal volumes of distilled water.The neuroethology of the surviving rats was measured; The volume of cerebral infarction in rats was measured by TTC method; The histopathology of rat brain was observed by HE method; The expression levels of tumor necrosis factor α(TNF-α),interleukin-1β(IL-1β),interleukin-6(IL-6),malondialdehyde(MDA),superoxide dismutase(SOD) and catalase(CAT) in serum were detected by ELISA;The mRNA expressions of Notch 1,Jagged 1,Hes 1 and Bcl-2 in rat brain were detected by RT-PCR;Western blot was used to detect the expression levels of caspase-3 protein in rat brain; the expression levels of vascular endothelial growth factor(VEGF) and CD34 positive cells in rat brain were detected by immunofluorescence.The low, medium and high dose groups of Ershiwuwei Zhenzhu Pills and nimodipine group could significantly reduce the neurobehavioral score and cerebral infarction volume of rats with permanent middle cerebral artery occlusion, reduce the morphological changes of nerve cells, decrease the expression of TNF-α,IL-1β and IL-6 in rat serum, increase the activity of SOD and CAT,and reduce the level of MDA.Furthermore, the expression levels of Notch l, Jagged l, Hes l and Bcl-2 mRNA were significantly increased, and the expression level of caspase-3 protein was decreased.Meanwhile, the number of VEGF and CD34 positive cells increased in the treatment group.The differences were statistically significant. Ershiwuwei Zhenzhu Pills has a protective effect on ischemic stroke rats, and its mechanism may be related to anti-inflammation, anti-oxidation, promotion of nerve cell proliferation, inhibition nerve cell apoptosis and promotion of angiogenesis.

Baicalin treats cerebral ischemia reperfusion-induced brain edema in rats by inhibiting TRPV4 and AQP4 of astrocytes / 中国中药杂志

This study aims to explore the pharmacodynamic effect of baicalin on rat brain edema induced by cerebral ischemia reperfusion injury and discuss the mechanism from the perspective of inhibiting astrocyte swelling, which is expected to serve as a refe-rence for the treatment of cerebral ischemia with Chinese medicine. To be specific, middle cerebral artery occlusion(suture method) was used to induce cerebral ischemia in rats. Rats were randomized into normal group, model group, high-dose baicalin(20 mg·kg~(-1)) group, and low-dose baicalin(10 mg·kg~(-1)) group. The neurobehavior, brain index, brain water content, and cerebral infarction area of rats were measured 6 h and 24 h after cerebral ischemia. Brain slices were stained with hematoxylin and eosin(HE) for the observation of pathological morphology of cerebral cortex after baicalin treatment. Enzyme-linked immunosorbent assay(ELISA) was employed to determine the content of total L-glutathione(GSH) and glutamic acid(Glu) in brain tissue, Western blot to measure the content of glial fibrillary acidic protein(GFAP), aquaporin-4(AQP4), and transient receptor potential vanilloid type 4(TRPV4), and immunohistochemical staining to observe the expression of GFAP. The low-dose baicalin was used for exploring the mechanism. The experimental results showed that the neurobehavioral scores(6 h and 24 h of cerebral ischemia), brain water content, and cerebral infarction area of the model group were increased, and both high-dose and low-dose baicalin can lower the above three indexes. The content of GSH dropped but the content of Glu raised in brain tissue of rats in the model group. Low-dose baicalin can elevate the content of GSH and lower the content of Glu. According to the immunohistochemical staining result, the model group demonstrated the increase in GFAP expression, and swelling and proliferation of astrocytes, and the low-dose baicalin can significantly improve this situation. The results of Western blot showed that the expression of GFAP, TRPV4, and AQP4 in the cerebral cortex of the model group increased, and the low-dose baicalin reduce their expression. The cerebral cortex of rats in the model group was severely damaged, and the low-dose baicalin can significantly alleviate the damage. The above results indicate that baicalin can effectively relieve the brain edema caused by cerebral ischemia reperfusion injury in rats, possibly by suppressing astrocyte swelling and TRPV4 and AQP4.

Neuroprotective effects of zonisamide on cerebral ischemia injury via inhibition of neuronal apoptosis

It is known that neuronal apoptosis contributes to pathology of cerebral ischemia injury. Zonisamide (ZNS) has shown anti-apoptosis effects in recent studies. The present study investigated whether the anti-apoptotic effect can account for the neuroprotective action of ZNS on cerebral ischemia. Neuronal cells were maintained under oxygen-glucose deprivation conditions to simulate cerebral ischemia and treated with ZNS simultaneously. The apoptosis of the cells and expression of apoptosis-related proteins were investigated by flow cytometry and western blot analysis, respectively. A cerebral ischemia mouse model was created via middle cerebral artery occlusion, and the mice were treated with ZNS. Neurological deficit scores and infarct volumes of the cerebral ischemia mice were measured. The apoptosis status of the neuronal cells was evaluated by TUNEL staining. In vitro, the ZNS treatment inhibited both the apoptosis of the neuronal cells and apoptosis-related protein expression (caspase-3, caspase-8, and calpain-1) induced by the oxygen-glucose deprivation. The anti-apoptosis effect of ZNS could occur through the blocking of reactive oxygen species. Moreover, ZNS treatment significantly ameliorated neurological deficits and reduced infarct volumes in the cerebral ischemia mice model. In this study, ZNS exerted neuroprotective effects by inhibition of apoptosis in neuronal cells in cerebral ischemia. Therefore, ZNS might be a promising therapy for cerebral ischemia.

Trombolisis endovenosa post reversión de acenocumarol con complejo de protrombina: caso clínico / Intravenous thrombolysis after reversion of acenocoumarol anticoagulation: report of one case

We report an 89-year-old male under oral anticoagulant therapy with a therapeutic international normalized ratio, presenting at the emergency room with right side hemiparesis and aphasia. Neuroimaging was compatible with an acute middle cerebral artery ischemic stroke. Anticoagulation was reverted with the use of four factor prothrombin complex, followed by thrombolysis with alteplase, with a favorable evolution, returning to his basal functional status.

Does the side of middle cerebral artery compromise matters in the mortality after thrombolysis in ischemic stroke? / O lado acometido da artéria cerebral média interfere na mortalidade do acidente vascular isquêmico pós trombólise?

The impact of the side in middle cerebral artery (MCA) ischemic stroke is not well established. Our aim was to analyze the differences between right (RMCA) and left middle cerebral artery (LMCA) stroke in patients submitted to intravenous thrombolysis and the influence of the affected side in the patient’s mortality after 3 months. Method Patients with MCA ischemic stroke submitted to intravenous thrombolysis from March 2010 to December 2011 at two Brazilian Stroke Centers were included. Differences between patients with RMCA and LMCA stroke were identified by univariate analysis. Results Forty-five patients with RMCA stroke and 67 with LMCA stroke were analyzed. Patients with LMCA had a higher incidence of atrial fibrillation (p = 0.031), although patients with RMCA more often had a previous ischemic stroke (p = 0.034). The mortality over 3 months was similar for either side (OR = 1.20 ;0.37 - 4.29, p = 0.772). Conclusion The side of the MCA ischemic stroke did not influence the patients mortality. .

O impacto do lado de acometimento da artéria cerebral média (ACM) não é bem estabelecido. Nosso objetivo é analisar as diferenças entre pacientes com acidente vascular isquêmico (AVCi) de ACM direita (ACMD) e esquerda (ACME) submetidos à trombólise endovenosa e a influência do lado acometido na mortalidade em 3 meses. Método Pacientes com AVCi ACMD e ACME submetidos à trombólise endovenosa entre Março de 2010 a Dezembro de 2012 em duas Unidades de AVC brasileiras foram incluídos. Diferenças entre AVCi ACMD e ACME foram identificadas pela análise univariada. Resultados Quarenta e cinco pacientes com AVCi de ACMD e 67 de ACME foram analisados. Pacientes com AVCi de ACME tiveram maior incidência de fibrilação atrial (p = 0,031), enquanto de ACMD maior de AVCi prévio (p = 0,034). A mortalidade em 3 meses foi similar em ambos os grupos (OR = 1,20; 0,37 -4,29, p = 0,772). Conclusão O lado de acometimento da ACM no AVCi não influencia na mortalidade. .

Atorvastatin protects GABAergic and dopaminergic neurons in the nigrostriatal system in an experimental rat model of transient focal cerebral ischemia / La atorvastatina protege las neuronas gabérgicas y dopaminérgicas del sistema nigroestriatal en un modelo experimental de isquemia cerebral focal transitoria en ratas

Introduction: Cerebral ischemia is the third leading cause of death and the primary cause of permanent disability worldwide. Atorvastatin is a promising drug with neuroprotective effects that may be useful for the treatment of stroke. However, the effects of atorvastatin on specific neuronal populations within the nigrostriatal system following cerebral ischemia are unknown. Objective: To evaluate the effects of atorvastatin on dopaminergic and GABAergic neuronal populations in exofocal brain regions in a model of transient occlusion of the middle cerebral artery. Materials and methods: Twenty-eight male eight-week-old Wistar rats were used in this study. Both sham and ischemic rats were treated with atorvastatin (10 mg/kg) or carboxymethylcellulose (placebo) by gavage at 6, 24, 48 and 72 hours post-reperfusion. We analyzed the immunoreactivity of glutamic acid decarboxylase and tyrosine hydroxylase in the globus pallidus, caudate putamen and substantia nigra. Results: We observed neurological damage and cell loss in the caudate putamen following ischemia. We also found an increase in tyrosine hydroxylase immunoreactivity in the medial globus pallidus and substantia nigra reticulata, as well as a decrease in glutamic acid decarboxylase immunoreactivity in the lateral globus pallidus in ischemic animals treated with a placebo. However, atorvastatin treatment was able to reverse these effects, significantly decreasing tyrosine hydroxylase levels in the medial globus pallidus and substantia nigra reticulata and significantly increasing glutamic acid decarboxylase levels in the lateral globus pallidus. Conclusion: Our data suggest that post-ischemia treatment with atorvastatin can have neuro-protective effects in exofocal regions far from the ischemic core by modulating the GABAergic and dopaminergic neuronal populations in the nigrostriatal system, which could be useful for preventing neurological disorders.

Introducción. La isquemia cerebral es la tercera causa de muerte y la primera de discapacidad permanente en el mundo. La atorvastatina es un fármaco neuroprotector prometedor para el tratamiento de la apoplejía; sin embargo, su acción sobre las poblaciones neuronales del sistema nigroestriatal después de la isquemia aún se desconoce. Objetivo. Evaluar el efecto de la atorvastatina sobre poblaciones gabérgicas y dopaminérgicas en regiones exofocales en un modelo de oclusión transitoria de la arteria cerebral media. Materiales y métodos. Se utilizaron 28 ratas Wistar macho de ocho semanas de edad. Los ejemplares con isquemia simulada y los ejemplares sometidos a isquemia fueron tratados con atorvastatina (10 mg/kg) y carboximetilcelulosa (placebo) administrados por medio de sonda a las 6, 24, 48 y 72 horas después de la reperfusión. Se analizó la inmunorreacción de la descarboxilasa del ácido glutámico y de la tirosina hidroxilasa en el globo pálido, el putamen caudado y la sustancia negra. Resultados. Los datos confirmaron el daño neurológico y la pérdida celular en el putamen caudado. Se incrementó la inmunorreacción de la tirosina hidroxilasa en el globo pálido medial y la sustancia negra pars reticulata , disminuyendo la inmunorreacción de la descarboxilasa del ácido glutámico en el globo pálido lateral de los animales isquémicos tratados con placebo; sin embargo, el tratamiento con atorvastatina pudo revertirla, lo que logró una disminución significativa de la tirosina hidroxilasa en el globo pálido medial y la sustancia negra pars reticulata y aumentando los niveles de descarboxilasa del ácido glutámico en el globo pálido lateral. Conclusión. Nuestros datos sugieren que la atorvastatina en el tratamiento posterior a la isquemia ejerce neuroprotección en las zonas exofocales, modulando las poblaciones neuronales gabérgicas y dopaminérgicas del sistema nigroestriatal, lo que podría prevenir trastornos neurológicos.

Evaluation of effects of memantine on cerebral ischemia in rats

To evaluate the effects of memantine on infarct size in cerebral ischemia and on neurological outcome after temporary middle cerebral artery occlusion [MCAO] and reperfusion in rats. In this study, performed between 2002-2004 in Dicle University School of Medicine, Diyarbakir, Turkey, 30 adult Sprague-Dawley rats were used. Cerebral ischemia was constituted by the intraluminal filament method with a 4-0 nylon suture. Reperfusion was started after 2 hours of MCAO. The rats were randomly divided into 2 groups as control and memantine. Saline 0.9% [0.5 ml/kg] and memantine [30 mg/kg] were administered via nasogastric intubations. Three coronal slices of 2 mm thickness were obtained from cerebrum, cerebellum, and brain stem, and were stained with a 2% solution of triphenyltetrazolium chloride. Transparent sheets were placed over each section and the areas of the brain and infarct were measured. Forty-five slices from each group [total 90] were obtained. Percent of ischemic area [%] in cerebrum, cerebellum, and brain stem level in memantine was lower than those of the control group [p=0.0001]. In addition, we determined an improvement in neurological score at 24th and 72nd hours in the rats that have been given memantine. The memantine group showed significantly better recovery than the control group [p=0.0001]. We concluded that memantine may decrease ischemic area in experimental cerebral ischemia in rats and it seems that memantine may be beneficial in cerebral ischemia

Effect of dichloracetate on infarct size in a primate model of focal cerebral ischaemia.

Acidosis is a major contributing factor towards spread of the ischaemic focus in the brain. Drugs that increase pyruvate dehydrogenase activity could decrease the formation of lactic acidosis. The sodium salt of dichloracetic acid (DCA) has been found to be effective in reducing lactate. This study was undertaken to study the efficacy of DCA in reducing infarct size in experimental focal ischaemia in monkeys. Macaca radiata monkeys in the treatment group were given 35 mg per kilogram of dichloracetate intravenously immediately before occluding and interrupting the middle cerebral artery, and the control group was given saline as placebo under similar conditions. Mean infarct size expressed as a percentage of the size of the hemisphere in all the three brain slices was 35.38 in the control group as against l2.06 in the treated group (p=0. 0008).