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Aim To investigate the effect of safflower yellow (SY) on learning and memory ability of APP/ PS1 mice at different disease stages, and to explore the mechanism of SY anti- Alzheimer's disease by using 3-,6- and 9-month-old APP/PS 1 transgenic mice as experimental animal models. Methods Behavioral experiments were conducted to observe the effects of SY on learning and memory of APP/PS1 mice of different months. ELISA was used to detect the effect of SY on the expression of inflammatory factors in cortex of mice of different months. Western blot was used to detect the microglia activation marker protein, and its mechanism of action was further analyzed. Results SY could enhance the learning and memory ability of mice aged 3, 6 and 9 months, reduce the content of IL-6 and increase the content of TGF-β1 in brain tissue, up-regulate the expression levels of arginase-1 (arg-1) and triggering receptor expressed on myeloid cells 2 (tREM2) in brain tissue of mice of different months, and down-regulate the expression levels of inducible nitric oxide synthase (iNOS), Toll-like receptors 4 (tlr4) and nuclear factor-kappa B (nf-KB). Conclusions Compared with 3- and 9-month-old mice, SY is the most effective in improving learning memory in 6-month-old APP/PS1 mice. SY inhibits TLR4/NF-KB pathway activation by inducing TREM2 expression in brain tissue of APP/PS 1 transgenic mice, promotes microglia phenotype shift to anti-inflammatory phenotype, reduces chronic neuroinflammatory response, and improves learning memory in APP/PS1 mice at all months of age.
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Objective:To investigate the effects of 40 Hz and 70 Hz frequency flash stimulation on the ability of learning memory and autonomous exploratory in young rats.Methods:Twenty-seven SPF grade male SD rats aged 19-21 days were divided into control group (Ctr group), 40 Hz group and 70 Hz group with 9 in each group according to the random number table.The rats in Ctr group were not given flash stimulation, while rats in the 40 Hz and 70 Hz group were received 40 Hz, 70 Hz flash stimulation (1.5 h/d for 39 days), respectively.The Morris water maze experiment was used to assess the learning and memory ability of rats, and the open field experiment was used to evaluate the ability of autonomous exploratory of rats.Nissl staining was used to assess the morphology of Nissl bodies in the hippocampus CA1 region of the rats.The local field potentials (LFPs) collected from the primary visual cortex (V1 area) region by electrophysiological experiments was used to verify the synchronization of flash evoked neural oscillations.SPSS 23.0 software was used for statistical analysis.The repeated measures ANOVA and one-way ANOVA were used to analyze normal distribution measurement data, and LSD and Tamhane tests were used for further pairwise comparison.The Kruskal-Wallis test was used for non-normal distribution measurement data.Results:(1) The flash stimulation of 40 Hz and 70 Hz both can effectively caused synchronization of neural oscillations in the primary visual cortex of healthy young rats.(2) The results of repeated measures ANOVA analysis showed that there was no interaction effect of grouping and time in the escape latency of young rats in the Morris water maze positioning navigation phase( F=1.326, P>0.05 ). The escape latency had time main effect ( F=40.025, P<0.05), but no grouping main effect ( F=2.039, P>0.05). With the increase of learning days, the escape latency of young rats in each group decreased significantly.There was no interaction effect of grouping and time in the total distance of young rats ( F=2.029, P>0.079). It had time main effect ( F=32.052, P<0.05), but not grouping main effect ( F=2.390, P>0.05) on total distance.With the increase of learning days, the total distance of young rats in each group significantly shortened.On the 6th day of the Morris water maze experiment, there was no statistically significant difference among groups in terms of time in the target quadrant and the number of crossing platforms ( F=2.511, 0.802, both P>0.05). The results of the open field experiment showed that the total distance traveled in the center of young rats in each group was statistically significant ( H=8.935, P<0.05), the total distance traveled in the center in the 70 Hz group (3.80 (2.25, 6.93) m)was significantly longer than that in the 40 Hz group (0.80 (0.72, 1.46) m), P<0.05). The percentage of time spent in the center was statistically significant in the three groups ( H=11.050, P<0.05). Young rats in the 70 Hz group spent significantly higher percentage of time in the center(3.20(2.43, 8.30)) than those in the 40 Hz group (0.95 (0.37, 1.06 ), P<0.05 ). (3) Nissl staining results showed that Nissl bodies in the hippocampal CA1 area of young rats in Ctr, 40 Hz and 70 Hz group were all arranged neatly and tightly, no edema was found in the surrounding stroma, and no obvious inflammatory cell infiltration was found. Conclusion:70 Hz frequency flash stimulation may promote the ability of learning memory and autonomous exploratory of young rats.
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Objective:To observe the effect of α-lipoic acid(ALA) on the intracerebroventricular injection(icv) of streptozotocin(STZ)-induced spatial learning memory impairments in rats and the underlying molecular mechanisms.Methods:Forty-five male SD rats were assigned into 3 groups, control group, icv-STZ group and icv-STZ+ ALA group, 15 rats each. STZ was dissolved in artificial cerebrospinal fluid then injected into the lateral ventricles of the rat by using stereotaxic device. ALA was administrated by gavage after STZ injection. The spatial learning memory was examined by using Morris water maze test after 4 weeks of treatment. Immunohistochemistry was performed to detect the number of microglia and astrocytes, electron microscopy was applied to detect mitochondrial integrity, Western blotting was used to detect the protein expression levels, and the changes of lipid peroxidation and redox system were examined by kit.Results:Spatial learning memory was impaired in rats after 4 weeks of STZ injection, and ALA treatment ameliorated STZ-induced cognitive dysfunction in rats. Iron concentration, lipid peroxidation, neuroinflammation, Tau hyperphosphorylated were enhanced markedly after STZ injection, along with and the activation of MAPK and GSK-3β, which were ameliorated by ALA. Further examination revealed that STZ activated the JAK2/STAT3 pathway and transcriptionally inhibited the expression of peroxidase GPX. Inhibition of STAT3 activity can block STZ-induced downregulation of GPX4 and Tau hyperphosphorylation.Conclusion:ALA ameliorated STZ-induced spatial learning memory impairments in rats via deactivation of JAK2/STAT3 pathway, restored GPX4 protein level, resulting in chelating iron, improving mitochondrial function, balancing the redox system, ameliorating Tau hyperphosphorylation and neuroinflammation.
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Porpouse: To systematically review the mechanisms by WBV improves the ability to learn, think, memorize and all other processes involving cognition. Methods: The present study collected data from three databases using the keywords "whole-body-vibration" and "cognition". Randomized clinical trials focusing on the association of WBV and cognition were considered. The study was registered in the database of systematic reviews protocols PROSPERO. All included studies used healthy patients, exposed to WBV. The included articles were obtained regarding the risk of bias according to the Cochrane Collaboration criteria, level of evidence and strength of recommendation following the GRADE and Oxford classification. Results: Of the 89 articles published to the eligibility criteria, four were submitted to data extraction. Cognitive parameters were improved in relation to attention, memory or learning in almost all articles evaluated in this systematic review. Conclusion: Intervention with WBV would positive effects on individuals' cognitive ability, although further randomized investigations must be conducted. PROSPERO registration number: CRD42020203679
Objetivo: Revisar sistematicamente os mecanismos pelos quais a vibração de corpo inteiro (VCI) melhora a capacidade de aprender, pensar, memorizar e todos os outros processos que envolvem a cognição. Método: O presente estudo coletou dados de três bancos de dados usando as palavras-chave "vibração de corpo inteiro" e "cognição". Ensaios clínicos randomizados com foco na associação de WBV e cognição foram considerados. O estudo foi registrado no banco de dados de protocolos de revisões sistemáticas PROSPERO. Todos os estudos incluídos usaram pacientes saudáveis, expostos à VCI. Os artigos incluídos foram avaliados quanto ao risco de viés de acordo com os critérios da Colaboração Cochrane, nível de evidência e força de recomendação segundo a classificação GRADE e Oxford. Discussão e Resultados: Dos 89 artigos publicados, de acordo com os critérios de elegibilidade, quatro foram submetidos à extração de dados. Os parâmetros cognitivos, atenção, memória e aprendizagem demonstraram melhora em quase todos os artigos avaliados nesta revisão sistemática. Conclusão: A intervenção com VCI teria efeitos positivos na capacidade cognitiva dos indivíduos, embora mais ensaios clínicos randomizadas devam ser realizados para avaliação de tais parâmetros. Número de registro PROSPERO: CRD42020203679
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Objective:To explore the mechanism of Suanzaoren Tang in improving learning-memory of sleep-deprived rats based on Nod-like receptor 3 (NLRP3) inflammatome pathway. Method:The rats were randomly divided into normal control group, model group, Eszolam group(5.4×10<sup>-4</sup> g·kg<sup>-1</sup>·d<sup>-1</sup>), low-dose Suanzaoren Tang group(4.59 g·kg<sup>-1</sup>·d<sup>-1</sup>)and high-dose Suanzaoren Tang group (18.36 g·kg<sup>-1</sup>·d<sup>-1</sup>). In addition to normal control group, other groups were used to constructed sleep-deprived model, which was concurrent with 30-day continuous drug administration. Water maze was used to evaluate the learning-memory function of rats; The mRNA and protein expressions of NLRP3, apoptosis-related speckle proteins (ASC), aspartic acid-specific cysteine protease-1 (Caspase-1), interleukin-1(IL-1) and IL-18 in the hippocampus of rats were detected by Real-time fluorescence quantitative polymerase chain reaction (Real-time PCR) and Western blot. Result:Compared with control group, the incubation period of the platform, the total distance of swimming and the duration of first reaching the platform in model group were significantly increased (<italic>P</italic><0.01), while the number of platform crossings and the target quadrant time were decreased (<italic>P</italic><0.01). Compared with the model group, the incubation period, total swimming distance and the duration of first reaching the platform in low-dose Suanzaoren Tang group and high-dose Suanzaoren Tang group were decreased to different degrees (<italic>P</italic><0.05,<italic>P</italic><0.01), while the number of platform crossings and the target quadrant time were increased significantly (<italic>P</italic><0.05,<italic>P</italic><0.01),but with no significant change in estazolam group. Compared with normal control group, mRNA and protein expressions of NLRP3, ASC, Caspase-1, IL-1<italic>β</italic>, IL-18 in the hippocampus of the model group were significantly increased (<italic>P</italic><0.05,<italic>P</italic><0.01). Compared with model group, mRNA and protein expressions of NLRP3, ASC, Caspase-1, IL-1<italic>β</italic> and IL-18 in the hippocampus of the rats in low-dose Suanzaoren Tang group and high-dose Suanzaoren Tang group were all decreased to different degrees (<italic>P</italic><0.05). The mRNA and protein expressions of NLRP3, ASC, Caspase-1, IL-1<italic>β</italic> and IL-18 in the hippocampus of Suanzaoren group also decreased, but with no significant change. Conclusion:Suanzaoren Tang can improve the learning-memory function of sleep-deprived rats, and its mechanism is related to the inhibition of NLRP3 inflammatome pathway in hippocampus and the alleviation of neuroinflammation.
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Abstract Hippocampus is a part of the brain that has a major role in spatial learning and memory which can be affected by herbal extracts. Incense resin (Styrax benzoin) has been used by local communities to improve intelligence. However, there is no scientific evidence of the functions of Styrax benzoin for regulating hippocampal function. The aim of this study was intended to analyze and investigate the effect of incense resin on learning, memory, and dendrite complexity of mice. Three months old male Deutch Democratic Yokohama (DDY) mice were injected orally with graded doses of 100, 150, and 200 mg/kg of incense resin aqueous extract daily for 30 days. Spatial learning and memory performance levels were tested with Y-maze alternation, novel object recognition, and Morris water maze. The branches and maximum dendritic span in the dentate gyrus were observed by the Golgi-Cox staining. Overall, our results showed that incense resin extract increased learning and memory ability, and the number of dendrite branching in the dentate gyrus.
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Animaux , Mâle , Souris , Cellules dendritiques/effets des médicaments et des substances chimiques , Extraits de plantes/pharmacologie , Styrax/composition chimique , Apprentissage spatial/effets des médicaments et des substances chimiques , Mémoire/effets des médicaments et des substances chimiques , Administration par voie orale , Apprentissage du labyrinthe/effets des médicaments et des substances chimiquesRésumé
Objective:To observe the effect of Dabuyuan Jian on the synaptic plasticity of hippocampus and the brain derived neurotrophic factor (BDNF)/tyrosine kinase receptor (TrkB)/cyclic adenosine phosphate reactive element binding protein (CREB) signaling pathway in amyloid precursor protein/presenilil (APP/PS1) mice, and to explore its possible mechanism for improving synaptic plasticity. Method:Totally 36 APP/PS1 mice were divided into model group, donepezil group(6.5×10-4 g·kg-1·d-1) and Dabuyuan Jian group (13.2 g·kg-1·d-1), and another wild mice were set as control group. The mice in control group and model group received an equal volume of saline, and the mice in each group received drugs by gavage for 30 days. The learning ability and memory of mice in each group were detected by Morris water maze. The pathological changes of neurons and synapses in the hippocampus of each group were observed by Nissl staining and Golgi staining. The expression levels of postsynaptic density protein 95 (PSD95) and synaptophysin (SYN) in hippocampus of each group were detected by immunofluorescence (IF). The protein expression levels of BDNF, TrkB, CREB and phosphorylated CREB (p-CREB) in hippocampus were detected by Western blot. Result:As compared with the control group, the platform latency and total swimming distance of the model group were increased in the model group (P<0.01), with decreased times of crossing the platform and staying time in the target quadrant (P<0.01), the intracellular Nissl bodies of neurons in hippocampal CA3 area decreased or disappeared in model group, with decreased number of neurons and dendritic branches and decreased density of dendritic spine in hippocampal CA3 area of the mice (P<0.01), and the protein expression levels of SYN, PSD95, BDNF, TrkB and p-CREB in hippocampus of mice were also decreased in model group (P<0.05, P<0.01). As compared with the model group, the platform latency and total swimming distance were decreased in the donepezil group and Dabuyuan Jian group (P<0.05, P<0.01), with increased times of crossing platform and staying time in target quadrant (P<0.05, P<0.01), the number of Nissl bodies of neurons in hippocampal CA3 area was increased in the donepezil group and Dabuyuan Jian group, with increased number of neurons and dendritic branches and increased density of dendritic spine in hippocampal CA3 area of the mice, and the protein expression levels of SYN, PSD95, BDNF, TrkB and p-CREB in hippocampus of mice were increased in the donepezil group and Dabuyuan Jian group (P<0.05, P<0.01). Conclusion:Dabuyuan Jian can improve the synaptic plasticity of APP/PS1 double transgenic mice, and its mechanism may be related to its up-regulation of BDNF/TrkB/CREB signal pathway in mouse hippocampus.
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OBJECTIVE@#To explore the effect of early intervention electroacupuncture (EA) at "Baihui" (GV 20), "Dazhui" (GV 14) and "Shenshu" (BL 23) on the learning-memory ability and the expression of phosphorylated Tau protein in the hippocampus of SAMP8 mice, so as to provide reference for the intervening period of EA for Alzheimer's disease (AD).@*METHODS@#A total of 36 3-month old SAMP8 mice were randomly divided into a model group, a 3-month-old EA group and a 9-month-old EA group, 12 mice in each group. Twelve normal SAMR1 mice with the same age were taken as the control group. The mice in the 3-month-old EA group and 9-month-old EA group were treated with EA at "Baihui" (GV 20), "Dazhui" (GV 14) and "Shenshu" (BL 23) separately 3 months old and 9 months old (continuous wave, 2 Hz, 1.5-2 mA), 20 min each time, once a day, 8 days as a course of treatment, with an interval of 2 days between courses, totally 3 courses of treatment were given. The mice sample in each group was collected at the age of 10 months after the learning-memory ability tested by Morris water maze. The expression of phosphorylated Tau protein in the hippocampus was detected by immunohistochemistry and Western blot, and the expression of Tau mRNA was detected by real-time PCR.@*RESULTS@#Compared with the control group, in the model group, the escape latency was significantly increased (<0.01), the time of stay in the original platform quadrant and the number of crossing the platform quadrant were reduced (<0.01), and the expressions of phosphorylated Tau protein and Tau mRNA in hippocampus were increased (<0.01). Compared with the model group, in the 3-month-old EA group and 9-month-old EA group, the escape latency was significantly reduced (<0.05), the time of stay in the original platform quadrant and the number of crossing the platform quadrant were increased (<0.05), and the expressions of phosphorylated Tau protein and Tau mRNA in hippocampus were reduced (<0.05). Compared with the 9-month-old EA group, in the 3-month-old EA group, the escape latency was significantly reduced (<0.05), the time of stay in the original platform quadrant and the number of crossing the platform quadrant were increased (<0.05), and the expressions of phosphorylated Tau protein and Tau mRNA were reduced (<0.01).@*CONCLUSION@#The early EA intervention could more effectively improve the learning-memory ability and inhibit phosphorylation of Tau protein in the hippocampus of SAMP8 mice.
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Animaux , Souris , Modèles animaux de maladie humaine , Électroacupuncture , Hippocampe , Apprentissage , Mémoire , Protéines tauRésumé
OBJECTIVE@#To observe the effect of pretreatment of acupuncture on the expression of nucleotide-binding oligomerization domain-like receptor 3(NLRP3), Caspase-1, interleukin1β(IL-1β) and the number of activated microglia (MG) in the hippocampus in Alzheimer's disease (AD) like rats, so as to explore the mechanism of pretreatment of acupuncture in preventing and treating AD.@*METHODS@#A total of 36 SD rats were randomly divided into a blank group, a model group and an electroacupuncture (EA) group, 12 rats in each group. The AD like rat model was established by 8-week continuous intraperitoneal injection of D-galactose (120 mg·kg@*RESULTS@#Compared with the blank group, the average escape latency was prolonged (@*CONCLUSION@#Pretreatment of acupuncture could prevent and treat the learning-memory dysfunction in AD like rats, and its mechanism may be related to the inhibition of NLRP3 inflammatsome related protein and MG activation.
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Animaux , Rats , Maladie d'Alzheimer/thérapie , Électroacupuncture , Hippocampe , Inflammasomes , Protéine-3 de la famille des NLR contenant un domaine pyrine/génétique , Rat Sprague-DawleyRésumé
OBJECTIVE: To compare the effect of electroacupuncture (EA) of acupoint group for "reinforcing the kidney and regulating Governor Vessel" and acopoint group for "reinforcing the kidney and lung and regulating Governor Vessel" on lear-ning-memory ability and expression of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) proteins in the hippocampus and prefrontal cortex (PFC) in Alzheimer's disease (AD) rats, so as to explore the efficacy of the two acupoint groups and mechanisms underlying improvement of AD. METHODS: Forty male SD rats were randomly divided into control, sham operation, model, "Baihui" + "Shenshu" (GV20+BL23, for "reinforcing the kidney and regulating Governor Vessel") EA and GV20+BL23+ "Feishu" (BL13, GV20+BL23+BL13, for "reinforcing the kidney and lung and regulating Governor Vessel") EA groups (n=8 rats in each group). The AD model was established by bilateral injection of amyloid β peptide (Aβ25-35,10 μL) into bilateral hippocampus, and rats of the sham operation group received injection of normal saline. After successful establishment of the model,EA (2 Hz, 2 mA) was applied to these acupoints for 15 min, once daily for 10 days. Then, the learning-memory ability was assessed by using Morris water maze tests, and the expression levels of TNF-α and IL-1β proteins in the PFC and hippocampus tissues were detected by using Western blot. RESULTS: Following modeling, the average escape latency of place navigation test were significantly increased (P0.05). CONCLUSION: EA of both GV20+BL23 and GV20+BL23+BL13 acupoint can improve learning-memory ability of AD rats, which is associated with their effects in down-regulating the expression of IL-1β and TNF-α in the PFC and hippocampus to reduce inflammatory reaction. There were no significant differences between the two acupoint groups in the therapeutic effects.
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OBJECTIVE: To investigate the effect of electroacupuncture (EA) at "Baihui"(GV20), "Fengfu"(GV16) and bilateral "Shenshu"(BL23) on learning-memory ability, apoptosis in the hippocampus and expression of Aβ, Caspase 3, Bax and Bcl-2 proteins in the hippocampus and cerebral cortex in immature mice with Alzheimer's disease (AD), so as to explore its mechanism underlying improvement of AD. METHODS: Forty APP/PS1 transgenic male young mice were equally randomized into model and EA groups and 20 C57BL/6J male young mice were used as the normal control. EA (10 Hz, about 2 mA) was applied to GV20-BL23 and GV16-BL23 for 20 min, once daily, 6 days a week for 16 weeks. The Morris water maze swimming test was used to evaluate the animals' learning-memory ability. Congo red staining and immunohistochemical staining were used to detect senile plaques in the hippocampus (dentate gyrus) and cerebral cortex tissues. Terminal deoxynucleotidyl transferase-mediated dUTP Nick-end Labeling (TUNEL) was used to detect the cellular apoptosis of hippocampus. The expression levels of apoptosis related factors Caspase 3, Bax and Bcl-2 were detected by Western blot. RESULTS: After modeling, the escape latency of place navigation test of Morris water maze swimming tasks was significantly increased (P0.05). CONCLUSION: EA of GV20, GV16 and BL23 can effectively improve the learning-memory ability in AD mice, which may be related to its function in inhibiting neuronal apoptosis in the hippocampus and down-regulating the expression levels of Aβ, Caspase 3 and Bax proteins in both hippocampus and cerebral cortex.
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OBJECTIVE: To observe the effect of electroacupuncture (EA) and manual acupuncture (MA) on learning-memory ability, changes of ultrastructure of neurons and expression of CDK5 and Tau proteins in hippocampus of SAMP8 mice,so as to explore its mechanisms underlying improvement of Alzheimer's disease (AD).. METHODS: A total of 45 male SAMP8 mice were randomly divided into model, EA and MA groups, with 15 mice in each group. The other 15 SAMR1 mice were used as the normal group. In the EA group, EA (2 Hz, 1 mA) was applied to bilateral "Shenshu"(BL23) and manual acupuncture was applied to "Baihui"(GV20) for 20 min. In the MA group, MA was applied to GV20 and bilateral BL23 for 20 min. Both group were treated once a day for 31 days, and with an interval of one day between every two 7 days. Morris water maze was performed to assess the animals' learning-memory ability. The morphological changes of hippocampal neurons were observed under transmission electron microscopy. The expression levels of CDK5, p25 and Tau-5 proteins in the hippocampus were detected by immunohistochemistry and Western blot, separately. RESULTS: ①Compared with the normal group, the average escape latency of Morris water maze test was prolonged in the model group(P<0.05, P<0.01), duration of swimming in the original platform quadrant and the number of original platform crossing were significantly shorter and less respectively (P<0.01). Compared with the model group, the average escape latency in the EA group was shortened (P<0.05, P <0.01), the duration of swimming in the original platform quadrant and the number of original platform crossing were significantly prolonged and increased (P<0.01); The average escape latency in the MA group was shortened (P<0.05, P <0.01),and the duration of swimming in the original platform quadrant was prolonged (P<0.05). Compared with the EA group, the average escape latency of the MA group was prolonged (P<0.05), the duration of swimming in the original platform quadrant was shortened(P<0.05). ②Transmission electron microscopy revealed that the neurons in the hippocampal CA1 area had irregular shape and vague structure, reduction in size and number of mitochondria accompanied with swelling, and malformed changes of mitochondrial crest in the model group, which was relatively milder in both EA and MA groups. ③The expression levels of hippocampal Tau-5, p25 and CDK5 proteins were significantly up-regulated in the model group in contrast to the normal group (P<0.01, P<0.05), and obviously down-regulated in both EA and MA groups relevant to the model group (P<0.05, P<0.01). Compared with the EA group, the expression levels of p25 and CDK5 proteins were significantly increased in the MA group (P<0.05). CONCLUSION: EA of BL23 can improve the learning-memory ability in SAMP8 mice, which is associated with its effect in down-regulating the expression of hippocampal CDK5, p25 and Tau-5 proteins.
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OBJECTIVE: To investigate the effect of electroacupuncture (EA) combined with Donepezil on learning-memory ability and gene expression of β-amyloid (Aβ) clearance-related factors in the hippocampus in senescence-accelerated mouse prone 8 (SAMP8) mice, so as to explore their synthetic effect in improving dementia of Alzheimer's disease (AD).. METHODS: Male SAMP8 mice (30-week-old) were randomly divided into model, medication and EA+medication groups (n=6 mice in each group), and other 6 senescence-resistant 1 (SAMR1) mice were used as the control group. Mice of the medication and EA+medication group received gavage of Donepezil (1.3 mg•kg-1•d-1) once daily for 4 weeks. EA (2 Hz, 1 mA) was applied to "Baihui"(GV20) and "Yintang" (EX-HN3) for 15 min, once daily, 6 days a week for 4 weeks for rats in the EA+medication group. The Morris water maze (MWM) task (including place navigation tests and space exploration trials) was used to assess the mouse's learning-memory ability. Histopathological changes of hippocampus tissue were observed by H.E. staining. The expression levels of matrix metalloprotein 9 (MMP-9), low density lipoprotein receptor-related protein-1 (LRP-1), P-glycoprotein (Pgp, an important drug transporter responsible for multidrug resistance), Claudin-5 (a component of tight junction strands that serves as a physical barrier to prevent solutes and water from passing freely through the paracellular space between epithelial or endothelial cell sheets of blood-brain barrier, BBB) and Aβ mRNAs of the hippocampus tissue were detected by quantitative real-time PCR. RESULTS: Compared with the control group, the average escape latency of place navigation tests, and the expression levels of MMP-9 and Aβ mRNAs were significantly increased (P<0.01), and the number of platform quadrant-crossing times of space exploration trials, and the expression levels of LRP-1, Pgp and Claudin-5 mRNAs considerably decreased in the model group (P<0.01). After the intervention, the learning-memory ability was significantly improved in the medication and EA+medication groups (P<0.01,P<0.05), the expression levels of Aβ mRNAs in the medication and EA+medication groups and MMP-9 mRNA in the EA+medication group were obviously down-regulated (P<0.01), and those of LRP-1 and Pgp mRNAs in the medication and EA+medication groups and Claudin-5 mRNA in the EA+medication group were remarkably up-regulated (P<0.05, P<0.01). The therapeutic effect of EA+medication was apparently superior to that of simple medication in shortening the escape latency (P<0.05,P<0.01) and in down-regulating the expression of MMP-9 and Aβ mRNAs(P<0.01), and in increasing the number of platform quadrant-crossing times(P<0.01), and expression levels of LRP-1, Pgp and Claudin-5 mRNAs (P<0.01). H.E. staining showed scatted and loose arrangement of neurons in the hippocampus, with reduction of number of cell layers and unclear nucleoli, which was relatively milder in the medication and EA+medication groups. CONCLUSION: EA can enhance the effect of Donepezil in improving learning-memory ability in AD mice possibly by regulating expression of MMP-9, LRP-1, Pgp and Claudin-5 mRNAs and strengthening the effect of Donepezil in transporting Aβ via BBB.
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OBJECTIVE: To investigate the effect of acupuncture stimulation of head acupoints "Jin San Zhen" (JIN's Three Acupuncture Needles Therapy) on behavior reactions, hippocampal neuronal autophagy and expression of autophagy associated proteins (Beclin-1 and light chain 3 Ⅱ/Ⅰ [LC 3 Ⅱ/Ⅰ]) in rats with hypoxic-ischemic brain damage (HIBD) due to fetal intrauterine distress, so as to reveal its underlying mechanisms in improving neonatal HIBD. METHODS: Pregnant SD rats were used in the present study. The HIBD model was established by delayed caesarean delivery and bilateral uterine arteries clipping for 10 minutes. The HIBD rats were randomly divided into model group and acupuncture groups (n=9 rats in each group). The other 9 rats delivered naturally were used as the normal control group. On day 14 after delivery, the neonatal rats in the acupuncture group received acupuncture stimulation of head acupoints ("Nao San Zhen""Nie San Zhen" and "Zhi San Zhen") by twirling each needle leftward and rightward for 10 times, once a day for 14 d. The open field test and Morris water maze test were used to determine the locomotive activity and spatial learning-memory ability, respectively. The ultrastructure and autophagosomes in the hippocampal neurons were observed by transmission electron microscope. The contents and expression levels of Beclin-1 and LC3 Ⅱ/Ⅰ in the hippocampus tissues were detected by flow cytometry and Western blot, separately. RESULTS: Compared with the normal control group, the time to go out of the central region of open field test, and the escape latency and duration of first platform-quadrant-crossing of spatial exploration of Morris water maze tests were significantly increased (P<0.01,P<0.05,P<0.001), and the total distance and number of activities in the central region, and the target quadrant resistance time and number of platform-cros-sing remarkably decreased in the model group (P<0.01, P<0.05), suggesting a decline of both locomotor activity and learning-memory ability after modeling. The expression level (%) of Beclin-1 protein and ratio of LC3 Ⅱ/Ⅰ proteins were considerably increased in the model group (P<0.01). Following acupuncture interventions, the locomotor activity and spatial learning-memory ability were obviously increased (P<0.05,P<0.01,P<0.001), and the expression of Beclin-1 protein and ratio of LC3 Ⅱ/Ⅰ were further up-regulated relevant to the model group (P<0.001). Moreover, ultrastructural observation showed serrated change of nuclear membrane and widened perinuclear space, vacuolization in the mitochondria, dilation of endoplasmic reticulum and increase of autophagosomes in the hippocampal neurons in the model group. These situations were relatively milder in the acupuncture group. CONCLUSION: Acupuncture of head acupoints of "JIN San Zhen" may increase locomotor activity and learning-memory abi-lity in rats with HIBD due to fetal intrauterine anoxia, which is closely with its effect in promoting hippocampal neuronal autophagy via up-regulating the expression of Beclin-1 and LC3 Ⅱ/Ⅰ.
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OBJECTIVE: To observe the effect of electroacupuncture (EA) stimulation on the expression of c-Jun terminal kinase(JNK)signaling pathway-related proteins in the hippocampus of vascular dementia (VD) rats, so as to explore its mechanisms underlying improvement of VD. METHODS: Male Sprague-Dawley rats were randomly divided into sham operation, model and EA groups (n=10 rats per group). The VD model was prepared by repeated occlusion of the bilateral common carotid arteries for 10 min and reperfusion for 10 min (3 times in total). The rats in the EA group received EA (2 Hz, 2 mA) at "Dazhui"(GV14),"Baihui"(GV20), and bilateral "Housanli"(ST36) ,"Geshu"(BL17) for 10 min, once daily for 14 days. The learning-memory abi-lity was detected by Morris water maze tests, the distribution of hippocampal neurons detected by Nissl staining, and the apoptosis of hippocampal neurons detected by using TdT-mediated dUTP nick-end labeling (TUNEL) method. The expressions of JNK, phosphorylated JNK (p-JNK), cysteine-containing aspartate-specific proteases-8 (Caspase-8) and Caspase-3 proteins were detected by Western blot. RESULTS: After modeling and compared with the sham operation group, the escape latency was significantly prolonged (P<0.01) and the number of safe-platform quadrant crossing obviously decreased (P<0.01), suggesting a reduction of learning-memory ability. The number of hippocampal neurons was considerably reduced (P<0.01), and that of hippocampal apoptotic neurons remarkably increased in the model group (P<0.01). Whereas, the expression levels of hippocampal apoptosis-related proteins as JNK, p-JNK, Caspase-8 and Caspase-3, as well as the apoptotic index were significantly up-regulated (P<0.01). Following EA intervention, the learning-memory ability was apparently improved (P<0.01), and the number of hippocampal neurons was considerably increased (P<0.01), the hippocampal apoptotic cell number, apoptosis index and the expression levels of JNK, p-JNK, Caspase-8 and Caspase-3 were significantly down-regulated (P<0.01). CONCLUSION: EA intervention can improve the learning-memory ability of VD rats, which may be associated with its effects in reducing hippocampal apoptosis by suppressing JNK signaling pathway.
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Objective To observe the effect of β-carotene ( β-C ) on the learning and memory and the expression of caspase-3 and p-tau expression in hippocampus of obstructive sleep apnea syndrome ( OSAS) rats. Methods Twenty-four adult SD rats were randomly divided into normal control group, OSAS model group ( model group) and β-C intervention group (intervention group), with 8 rats in each group. A hypoxic chamber was used to establish an OSAS rat animal model. The rats in model group and intervention group were given by gavage before intragastric administration, and no treatment was performed in the normal group. After completion of the modeling, the Morris water maze was used to test the learning and memory ability of the experimental rats. Observing the pathological changes of hippocampal tissue in rats by HE staining. The protein expression of caspase-3 and p-tau in hippocampus was detected by Western Blotting. Results Escape latency time of model group in each time point were significantly prolonged than those in normal control group ( all P<0. 05), and escape latency time of intervention group at 2-5 d were significantly shorter than those in model group (all P<0. 05). The number of times of crossing the platform in model group was significantly less than that in normal control group and intervention group ( all P<0. 05). Compared with those in model group, the expression of caspase-3 and p-tau in normal control group and intervention group were significantly lower (all P<0. 05). Conclusion β-C can reduce the impairment of learning and memory ability caused by OSAS, and the mechanism may be related to its inhibition of caspase-3 and p-tau protein expression.
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Objective To determine the content of total alkaloids and their components in roots, stems, and leaves of Berberis wilsonae, and investigate the effects of their extracts and components on the improvement of learning and memory ability and anti-oxidant activity of mice. Methods In this study, the total alkaloid content of roots, stems, leaves, and roots, stem extracts and components of B. wilsonae was determined by acid dye colorimetry. The HPLC method and conditions were established for determination jateorhizine, palmatine, and berberine. The memory impairment mice model was established with scopolamine, and the root and stem extracts and components of B. wilsonae were ig administrated for 30 d. Jumping platform test and water maze test were used to detect the effect of roots and stem extracts and components on learning and memory, and the levels of MDA and T-SOD in serum was determinated by kit method. Results The results showed that the latency of the mice in step-down test was significantly prolonged (P < 0.01), and the reduction of the number of errors was also significant (P < 0.01). To a certain extent, the place navigation time in water maze was shortened (P < 0.01), and the number of errors was reduced significantly (P < 0.05). Extracts and components can significantly increase the level of T-SOD (P < 0.05, 0.01) in mice, and reduce the level of MDA significantly (P < 0.05, 0.01). Conclusion The extracts and components of B. wilsonae had a certain effect on the improvement of learning and memory ability of mice, and the anti-oxidant capacity in vivo was also improved.
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Objective To explore the effects of electroacupuncture at Baihui (DU20) and Shenting (GV24) on Alzheimer's disease, and possible mechanism for it.Methods A total of 24 eight-month-old APP/PS1 male mice were randomly divided into model group (n = 8), electroacupuncture group (n = 8) and non-acupoint group (n = 8), and other eight wild-type mice were as wild-type group.The electroacupuncture group accepted electroacupuncture at Baihui and Shenting, while the non-acupoint group accepted electroacupuncture at bilateral subcostal non-acupoint area, and the wild-type group and the model group accepted the same grasping and fixing, for 28 days. Then they assessed with Morris water maze test. The levels of β-amyloid protein (Aβ) and β-site amyloid precursor protein cleaving enzyme 1 (BACE1) in cerebral cortex were detected with immunohistochemistry and immunofluorescence respectively, and the level of BACE1 m RNA with RT-PCR.Results Compared with the model group, the escape latency decreased in the electroacupuncture group (P < 0.001), and the times crossing platforms increased (P < 0.001), while the expression of BACE1 and Aβ decreased (P < 0.001).Conclusion Electroacupuncture may improve the learning-memory ability by inhibiting the expression of BACE1 in the cerebral cortex of APP/PS1 mice to decreasing the level of Aβ.
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Aim: To observe the COX-2 pathway changes in hippocampus and cortex of rat offsprings following maternal inflammation during pregnancy. Methods: Female SD rats were randomly divided into control group and lipopolysaccharide (LPS) group. Rats in LPS group were intraperitonealy injected with LPS 300 μug · kg-1 on 11th, 14th and 18th day of pregnancy, while those in control group were given normal saline. Body weight of offspring rats on 3th, 10th, 20th and 30th day was recorded; on 30th day, the development of nervous system of the offspring rats was tested using water maze test, open field test and spontaneous activity test and so on; the histopathological changes of the hippocampus and cortex were detected by hematoxylineosin staining; the levels of inflammatory factors were measured by ELISA; the protein expression of COX-2 was measured by Western blot. Results: There were no significant differences in the body weight of offspring rats between NS group and LPS group (P >0. 05). In LPS group, it was found that the learning and memory function of rats were impaired, and horizontal movement and spontaneous activities were significantly reduced (P < 0. 05); the hippocampus and cortex neurons showed a significant nuclear pyknosis (P < 0. 05, P<0.01); the levels of PGD2, PGE2, PGI2, TNF- a, IL6 and IL-1 [J in hippocampus and cortex significantly increased (P < 0. 05, P < 0. 01); the protein expression of COX-2 in hippocampus and cortex significantly increased (P<0.01). Conclusions: COX-2 and downstream pathway are involved in the mechanism of brain injury in offsprings of pregnancy inflammation rats.
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OBJECTIVE: To observe the effect of moxibustion of acupoints of the Governor Vessel on the levels of cellular autophagy, β amyloid protein (Aβ) immunoactivity, and expression of LC3-Ⅰ, LC3-Ⅱ, p62 and p-P70S6K proteins in the hippocampal tissue of APPswe/PS1de9 (APP/PS1) double-transgenic Alzheimer's disease (AD) mice, so as to reveal its underlying mechanisms in improving AD. METHODS: APP/PS1 double-transgenic AD mice were randomly divided into AD model, moxibustion, autophagy-inducer (Rapamycin) and autophagy-inhibitor (3-MA)+moxibustion groups (n=10 in each group), and other 10 C57BL/6J male mice (the same age) were used as the normal control group. Herbal-cake (made of Chuanwu [Radix Aconiti Praeparata]) partitioned moxibustion was applied to "Baihui"(GV20), moxibustion was applied to "Fengfu"(GV16) and "Dazhui"(GV14), all for 20 min, once daily for 2 weeks, with one day's off between two weeks. For mice of the autophagy-inducer and 3-MA+moxibustion groups, Rapamycin (2 mg•kg-1•d-1) and 3-MA (1.5 mg•kg-1•d-1) were separately administered by intraperitoneal injection for 2 weeks. The cognitive ability was examined by Morris water maze tests, and the ultrastructural changes (including autophagic lysosomes, etc.) of hippocampal neurons were observed by using transmission electron microscopy. The immunoactivity of cerebral cortex and hippocampal Amyloid β peptide 1-42 (Aβ1-42) was detected by immunohistochemistry, and the expression levels of hippocampal LC3-Ⅰ, LC3-Ⅱ, p62 and p-P70S6K proteins were detected by Western blot. RESULTS: After modeling, the escape latency of Morris water maze tasks was prolonged in the model group than in the normal control group (P<0.05) and obviously shortened in the moxibustion and autophagy-inducer groups (not the autophagy-inhibitor group) than in the model group (P<0.05). Results of transmission electron microscope showed deformed, irregular or atrophic neurons with rough and incomplete and fuzzy nuclear membrane, and decreased intracellular autophagosomes in the hippocampus in the model group, and partial irregular, atrophic neurons with more autophagic vesicles and lysosomes in the moxibustion group. The expression levels of Aβ1-42 in both cerebral cortex and hippocampus tissues, and LC3-Ⅰ, p62 and p-P70S6K proteins in the hippocampus were consi-derably up-regulated in the model group relevant to the normal control group (P<0.01), and evidently down-regulated in both moxibustion and autophagy-inducer groups (not the autophagy-inhibitor group) than in the model group (P<0.01), while that of hippocampal LC3-Ⅱ protein and LC3-Ⅱ/Ⅰ ratio levels were obviously down-regulated in the model group relevant to the normal control group (P<0.01), and significantly up-regulated in both moxibustion and autophagy-inducer groups (not the autophagy-inhibitor group) than in the model group (P<0.01).. CONCLUSION: Moxibustion can improve the cognitive ability of APP/PS1 double-transgenic AD mice, which is associated with its effects in promoting hip-pocampal and cerebral cortex autophagy level, and down-regulating the expression levels of Aβ1-42, LC3-Ⅰ, p62 and p-P70S6K proteins in the hippocampus.