Effect of Modified Shuyuwan on Hippocampal Myelin Sheath Injury in Vascular Dementia Rats Through Cx43/Glu/AMPAR Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the effect and mechanism of modified Shuyuwan （SYW） on hippocampal myelin sheath injury in vascular dementia （VD） model rats. MethodSixty male SD rats of SPF grade were randomly divided into sham operation group， model group， and high-， medium- and low-dose modified SYW groups， with 12 rats in each group. The VD model was induced by bilateral carotid artery ligation in rats of the groups except for those of the sham operation group. After modeling， rats were screened by the water maze test， followed by drug treatment by gavage. Specifically， rats in the modified SYW groups were treated with modified SYW at 10， 5， 2.5 g·kg-1·d-1， accordingly， and those in other groups were administered with the same amount of normal saline. After intragastric administration for 28 days， the spatial learning and memory abilities of rats were detected by the water maze test. The hippocampal neuron structure was observed by hematoxylin-eosin （HE） staining. The content of hippocampal tumor necrosis factor （TNF）-α， interleukin-6 （IL-6）， and glutamate （Glu） was observed by biochemical detection. The hippocampal expression of myelin basic protein （MBP）， astrocyte activation marker glial fibrillary acidic protein （GFAP）， and connexin 43 （Cx43） was detected by immunofluorescence detection. The myelin sheath structure in the hippocampus was observed by the electron microscope. The α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor （AMPAR） and Cx43 protein expression was detected by Western blot. ResultCompared with the sham operation group， the model group showed prolonged escape latency （P<0.01）， decreased times of crossing the original platform and percentage of target quadrant detention time （P<0.01）， disordered neuron structure in the hippocampal CA1 region， loose myelin sheath lamella with blurry edge， up-regulated expression levels of TNF-α， IL-6， and Glu in the hippocampal CA1 region， especially Glu （P<0.01）， reduced expression of AMPAR （P<0.01）， increased protein expression of p-AMPAR and Cx43 （P<0.01）， significantly dwindled protein expression of MBP in the myelin sheath， and enhanced fluorescence co-labeled by GFAP and Cx43. Compared with the model group， the modified SYW groups showed shortened escape latency （P<0.05）， increased times of crossing the original platform and percentage of target quadrant detention time （P<0.05）， closely arranged hippocampal neuron structure， denser myelin sheath lamella with clear edge， down-regulated expression levels of TNF-α， IL-6， and Glu in the hippocampal CA1 region， especially Glu （P<0.01）， up-regulated AMPAR （P<0.01）， reduced protein expression of p-AMPAR and Cx43， especially in the high-dose group （P<0.01）， significantly elevated protein expression of MBP in the myelin sheath， and weakened fluorescence co-labeled by GFAP and Cx43， especially in the high-dose group. ConclusionModified SYW can improve the learning and memory abilities of VD rats， and the mechanism may be related to the inhibition of Cx43 expression， reduction of the release of Glu， inhibition of AMPAR-mediated inflammatory response to reduce the production of astrocyte marker GFAP， and promotion of the expression of MBP protein to alleviate myelin injury.

Effect of moxibustion on cognitive function and proteins related with apoptosis of hippocampal neurons in rats with vascular dementia / 中国针灸

OBJECTIVE@#To observe the effect of moxibustion on proteins related with apoptosis of hippocampal neurons in rats with vascular dementia (VD), and to explore the possible mechanism of moxibustion on improving VD.@*METHODS@#Thirty SD rats were selected from 100 rats (3 rats were excluded) and randomly divided into a normal group and a sham operation group, 15 rats in each group. The remaining 67 rats were treated with ischemia-reperfusion method at bilateral common carotid artery to establish VD model. The 45 rats with successful VD model were randomly divided into a model group, a moxibustion group and a medication group, 15 rats in each group. On the 7th day after successful modeling, the rats in the moxibustion group were treated with suspended moxibustion at "Guanyuan" (CV 4), "Mingmen" (GV 4) and "Dazhui" (GV 14), 15 min per acupoint, once a day; there was 1 d of rest after 6 d of moxibustion, and the treatment was given for 4 weeks. The rats in the medication group was treated with nimodipine tablets by gavage, 2 mg/kg per day, 3 times a day for 4 weeks. Before and after intervention, the Morris water maze test was used to detect the escape latency of rats in each group; after the intervention, the TUNEL method was used to detect the apoptosis rate of neurons in hippocampal CA1 area; the immunofluorescence double labeling method was used to detect the number of co-expression positive cells of B-cell lymphoma-2 (Bcl-2)/neuronal nuclear antigen (NeuN) and Bcl-2-associated X protein (Bax)/NeuN in hippocampal CA1 area; the immunofluorescence single labeling method was used to detect cytochrome C (cytC) and outer mitochondrial membrane receptor Tom20 (Tom20) in hippocampal CA1 area; the Western blot method was used to detect the p53 upregulated modulator of apoptosis (PUMA) in hippocampus.@*RESULTS@#Before intervention, compared with the normal group and the sham operation group, the escape latency in the model group, the moxibustion group and the medication group was prolonged (@*CONCLUSION@#Moxibustion could improve the cognitive function of VD rats, which may be related to reducing the expression of Bax, cytC, Tom20 and PUMA protein in hippocampal CA1 area, promoting the release of Bcl-2 and inhibiting the apoptosis of hippocampal neurons.

Effect of Allicin on Learning and Memory Ability of Vascular Dementia Rats and Its Mechanism / 中国实验方剂学杂志

Objective:To investigate the effect of allicin （ALL） on learning and memory ability of rats with vascular dementia （VD） and the possible mechanism. Method:The VD rats induced by modified bilateral common carotid artery occlusion （BCCAO） were randomly divided into the VD group， low- and high-dose ALL （ALL-L and ALL-H） groups， and the sham operation （S） group， with 15 rats in each group. In the ALL-L and ALL-H groups， ALL was injected into the femoral vein at 5 mg·kg^-1 and 20 mg·kg^-1， respectively， while the same volume of normal saline was injected in the S and VD groups， once a day， for two successive weeks. Morris water maze （MWM） was used to test the learning and memory ability of rats. Hematoxylin and eosin （HE） staining was conducted to observe the pathological changes in hippocampal tissue， followed by the detection of inflammatory factors tumor necrosis factor-<italic>α</italic> （TNF-<italic>α</italic>）， interleukin-6 （IL-6）， and IL-1<italic>β</italic> as well as oxidative stress indexes malondialdehyde （MDA）， superoxide dismutase （SOD）， and glutathione peroxidase （GSH-Px） in rat hippocampus. The apoptosis of hippocampal cells was detected by TdT-mediated dUTP Nick end Labeling（TUNEL） assay. The expression levels of apoptosis and autophagy-related proteins cysteinyl aspartate-specific protease-3 （Caspase-3）， B-cell lymphoma 2 （Bcl-2）， Bcl-2-associated X protein （Bax）， microtubule-associated protein light chain 3Ⅱ （LC3Ⅱ）， LC3Ⅰ， and the mammalian homolog of yeast ATG6 （Beclin 1） in hippocampus were determined by Western blot. Result:The comparison with the VD group revealed that the learning and memory abilities of rats in the ALL-H and ALL-L groups were significantly improved （<italic>P</italic><0.05）. The TNF-<italic>α</italic>， IL-6， IL-1<italic>β</italic>， and MDA levels in hippocampus were lowered （<italic>P</italic><0.05）， whereas the SOD and GSH-Px activities were enhanced （<italic>P</italic><0.05）. The apoptosis rates were declined （<italic>P</italic><0.05）， with an even lower rate noticed in the ALL-H group （<italic>P</italic><0.05）. The expression levels of Caspase-3， Bax， LC3Ⅱ/LC3Ⅰ ratio， and Beclin-1 in the ALL-H and ALL-L groups were significantly down-regulated in contrast to those in the VD group （<italic>P</italic><0.05）， while that of Bcl-2 was up-regulated （<italic>P</italic><0.05）. The ALL-H group exhibited better performances than the ALL-L group （<italic>P</italic><0.05）. Conclusion:ALL could improve the learning and memory ability of VD rats to some extent， which may be attributed to its inhibition against inflammatory reaction， oxidative stress， and neuronal apoptosis and autophagy.

Effect of Bushen Tongluo Prescription on Synaptic Plasticity of Hippocampal Neurons of Vascular Dementia Model Rats Based on PI3K/Akt/mTOR Pathway / 中国实验方剂学杂志

Objective:To explore the effect of Bushen Tongluo prescription （BSTLP） on the synaptic plasticity of hippocampal neurons in vascular dementia （VD） model rats and its mechanism. Method:SD male rats of SPF grade were selected. The rat model of VD was established by permanent bilateral ligation of the common carotid artery several times. The model rats were randomly divided into a model group， an insulin-like growth factor-1 （IGF-1， 20 μg·kg^-1） group， high-dose （3 g·kg^-1）， medium-dose （1.5 g·kg^-1）， and low-dose （0.75 g·kg^-1） BSTLP groups. A sham operation group was also set. Drugs were administered to rats by gavage once a day for four weeks. The model group and the sham operation group received the same volume of normal saline. After the last administration， all the rats were detected for spatial learning and memory by the Morris water maze. The apoptosis of hippocampal neurons was detected by terminal deoxynucleotidyl transferase （TdT） dUTP nick-end labeling （TUNEL） assay. The changes in synaptic morphological structure and the number of dendritic spines in hippocampal neurons were detected by Golgi's method. The expression levels of phosphatidylinositol 3-kinase （PI3K）， protein kinase B （Akt）， mammalian target of rapamycin （mTOR）， synaptophysin （SYP）， and amyloid precursor protein （APP） in hippocampal neurons were detected by Western blot. Result:Compared with the sham operation group， the model group showed prolonged escape latency， lengthened swimming distance， dwindled the number of times for the platform crossing after platform removal （<italic>P</italic><0.05）， increased apoptotic cells （<italic>P</italic><0.05）， declining synaptic dendritic spines （<italic>P</italic><0.05）， down-regulated expression levels of PI3K， Akt， mTOR， and SYP proteins， and up-regulated expression level of APP protein in hippocampal neurons （<italic>P</italic><0.05）. Compared with the model group， the BSTLP groups and the IGF-1 group showed shortened escape latency and swimming distance， increased number of times for the platform crossing after platform removal （<italic>P</italic><0.05），declining apoptotic cells （<italic>P</italic><0.05）， up-regulated expression levels of PI3K， Akt， mTOR， and SYP proteins， and down-regulated expression level of APP protein in hippocampal neurons （<italic>P</italic><0.05）. Compared with the IGF-1 group， the high-dose BSTLP group showed no significant difference in the escape latency， swimming distance， the number of times for the platform crossing after platform removal， apoptotic cells， synaptic dendritic spines， and expression levels of PI3K， Akt， mTOR， SYP， and APP proteins in hippocampal neurons. However， the differences were significant in the medium-dose and low-dose BSTLP groups （<italic>P</italic><0.05）. Conclusion:BSTLP can improve the learning and memory of rats with VD. The mechanism is presumedly related to the activation of thePI3K/Akt/mTOR pathway and improvement of synaptic plasticity of hippocampal neurons.

Effects of Naoluo Xintong Decoction on vascular dementia rats' memory and learning, and hippocampal neuronal intracellular calcium concentration / 中成药

AIM To study the effects of Naoluo Xintong Decoction (NLXTD) on vascular dementia (VD)rats' memory and learning,and hippocampal neuronal intracellular calcium concentration.METHODS Rats were divided randomly into model group,NLXTD group (8.54 g/kg),Huperzia-A group (0.06 mg/kg) and sham group.They were made into vascular dementia rats by the improved bilateral carotid artery ligation method (2-VO)thereafter if necessary.After one-month corresponding intragastric administration,the rats were ethologically evaluated by the Morris water maze experiment;their fluorescence intensity of hippocampal neuronal intracellular calcium concentration was determined by flow cytometry,and the expression levels of calcitonin gene related peptide (CGRP) and its hippocampus receptor were detected by enzyme-linked immunosorbent assay (ELISA).RESULTS Compared with the model group,rats in NLXTD group displayed overall superiority to those of the model group in terms of significantly shortened time of escape latency (P ＜0.01),significantly increased number through the platform and the times in the fourth quadrant (P ＜ 0.01),a lower fluorescence intensity indicating a lower hippocampal neuronal intracellular calcium concentration (P ＜ 0.05).CONCLUSION The significant improvement of memory and learning observed among VD rats' due to NLXTD intervention may be attributable to its efficacy in reducing the hippocampal neuronal intracellular calcium concentration by enhancing the expression levels of CGRP and its receptor.

Xiao-Xu-Ming decoction protects against chronic cerebral ischemia injury in rats and profile of differentially expression proteins analysis in hippocampus / 中国药理学与毒理学杂志

OBJECTIVE Vascular dementia (VD) refers to a progressive decline in memory and cognitive function caused by chronic cerebral ischemia. 2-Vessels occlusion (2-VO) has been widely used as a model of VD. Xiao-Xu-Ming decoction, a well-known traditional Chinese medicine prescrip-tion,has been widely used to treat stroke and sequelae of stroke.The present study was to investigate the mechanism of Xiao-Xu-Ming decoction(XXM) against chronic cerebral ischemia injury in rats. METHODS After XXM treatment, rats were performed a memory testing with Morris water maze and motor ability testing using prehensile test and inclined screen test.Neuronal plasticity was observed by immunofluorescent staining with MAP2 antibody. Differentially expressed proteins of rat hippocampus were analyzed by Label-free quantitative proteomics. RESULTS XXM significantly alleviated 2-VO-induced learning and memory deficits, motor ability dysfunction, and neuronal plasticity injury in rats. The mechanism might be involved in up-regulation of 39 proteins and down-regulation of 13 proteins in the hippocampus of rats after XXM treatment vs 2-VO group rats.Gene ontology and pathway analysis showed that the regulated proteins are mainly involved in oxidation reduction process, intracellular signaling cascade process, and protein catabolic process, etc. The signal pathways are mainly involved in ubiquitin mediated proteolysis and phosphatidylinositol signaling system. CONCLUSION Current findings provide new insights into the molecular mechanisms of XXM on chronic cerebral ischemia.

Effects of kaempferol on learning and memory in rats with chronic cerebral ischemia and possible mechanisms / 中国药理学通报

Aim To investigate the effects and possible mechanisms of kaemperol in the rats with chronic cere-bral ischemia.Methods Chronic cerebral hypoperfu-sion model was produced by permanent occlusion of bi-lateral common carotid arteries (2VO)in rats.After KAE treatment,the rats underwent Morris water maze and prehensile traction test.Neuronal morphology was observed using Nissl and HE staining.The activity of SOD and the content of MDA in brain tissue were de-termined.The DJ-1 protein expression was assayed by Western blot.Results Compared with 2VO model group,KAE significantly improved learning and memo-ry and the grasping ability.In addition,KAE signifi-cantly reduced brain tissue pathological injury induced by 2VO. Furthermore, KAE significantly increased SOD activity and enhanced antioxidant protein DJ-1 ex-pression in brain tissue.Conclusions KAE could sig-nificantly attenuate the cognitive impairment,limb bal-ance dysfunction and pathological injury in rats with chronic cerebral ischemia.The mechanism may be re-lated to improving the antioxidant system in vivo.

Electroacupuncture at the Wangu acupoint suppresses expression of inflammatory cytokines in the hippocampus of rats with vascular dementia / 西安交通大学学报(医学版)

Objective To examine whether electroacupuncture at the Wangu acupoint (GB 12 ) , whose position is similar to the cerebellar fastigial nucleus ,can reduce inflammatory cytokines in the hippocampus of rats with vascular dementia (VD) to provide theoretical evidence for treating VD with electroacupuncture .Methods Healthy Sprague‐Dawley rats ( n=54 ,300 -450 g) were randomly divided into three groups :sham surgery group ,VD group ,and electroacupuncture group .The ethologic scores of VD rats were evaluated and the mRNA expressions of inflammatory cytokines (TNF‐α,IL‐6 and IL‐1β) in the hippocampus were assessed and the hippocampal tissues were observed by hematoxylin‐eosin (HE) staining .Results Compared with VD group ,in electroacupuncture group the rats' learning ability improved significantly and the mRNA expressions of TNF‐α, IL‐6 and IL‐1β decreased . Simultaneously ,the damage extent of nerve cells in the hippocampal tissues decreased , and their morphology recovered to nearly normal .Conclusion Electroacupuncture at the Wangu acupoint can decrease the level of inflammatory cytokines in the hippocampus and reduce the damage extent of nerve cells in the hippocampus ,thus providing a new neuroprotective method for VD .

Mechanism arid Treatment of Vascular Dementia with Traditional Chinese Medicine / 国际中医中药杂志

Vascular dementia(VD)is caused by blockage of blood supply in brain leading to damage of brain tissue.The prevention and cure of VD has become an important task with China is stepping into a senile society.Researches of VD trated with traditional Chinese medicine in the recent 10 year are summarized in this paper.

Effect of Naomaitai Capsule on learning and memory abilities and cerebral lipid-peroxidation in rat with vascular dementia / 中草药

Objective To observe the effect of Naomaitai Capsule on the learning and memory abilities and cerebral lipid-peroxidation in rat with vascular dementia(VD).Methods Two VD models were(established).The first one was produced by occlusion of bilateral common carotid arteries in rats with the(following) steps: ischemia 20 min—reperfusion 10 min—ischemia 20 min.The learning and memory abilities were tested by Y type maze.Meanwhile,malondiadehyde(MDA) content and superoxide dismutase(SOD) activity in brain tissue of ischemia-reperfusion rats were measured.The second model was formed by injecting thrombin NS solution into internal carotid artery.The learning and memory abilities were studied by Y type Maze.The content of Evans blue in brain tissue was measured.Results In the model caused by cerebral ischemia-reperfusion,Naomaitai Capsule significantly improved the learning and memory abilities((P