Effect of aqueous extract of Corni Fructus on Aβ_(25-35)-induced brain injury and neuroinflammation in mice with Alzheimer's disease / 中国中药杂志

The purpose of this study was to investigate the effect of aqueous extract of Corni Fructus on β-amyloid protein 25-35(Aβ_(25-35))-induced brain injury and neuroinflammation in Alzheimer's disease(AD) mice to provide an experimental basis for the treatment of AD by aqueous extract of Corni Fructus. Sixty C57BL/6J male mice were randomly divided into a sham group, a model group, a positive control group(huperizine A, 0.2 mg·kg~(-1)), a low-dose aqueous extract of Corni Fructus group(1.3 g·kg~(-1)), a medium-dose aqueous extract of Corni Fructus group(2.6 g·kg~(-1)), and a high-dose aqueous extract of Corni Fructus group(5.2 g·kg~(-1)). The AD model was induced by lateral ventricular injection of Aβ_(25-35) in mice except for those in the sham group, and AD model mice were treated with corresponding drugs by gavage for 24 days. The behavioral test was performed one week before animal dissection. Hematoxylin-eosin(HE) staining was performed to observe the morphology of neurons in the hippocampal region. Flow cytometry was used to detect the apoptosis level of primary hippocampal cells in mice. ELISA kits were used to detect the levels of β-amyloid protein 1-42(Aβ_(1-42)) and phosphorylated microtubule-associated protein Tau(p-Tau) in mouse brain tissues. Immunofluorescence and Western blot were used to detect the expression of related proteins in mouse brain tissues. MTT assay was used to detect the effect of compounds in aqueous extract of Corni Fructus on Aβ_(25-35)-induced N9 cell injury. Molecular docking was employed to analyze the interactions of caffeic acid, trans-p-hydroxy cinnamic acid, isolariciresinol-9'-O-β-D-glucopyranoside, esculetin, and(+)-lyoniresinol with β-amyloid precursor protein(APP), interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α). Aqueous extract of Corni Fructus could improve the learning and memory abilities of Aβ_(25-35)-induced mice by increasing the duration of the autonomous activity, the rate of autonomous alternation, the preference coefficient, and the discrimination coefficient, and reduce Aβ_(25-35)-induced brain injury and neuroinflammation in mice by increasing the expression levels of interleukin-10(IL-10) and B-cell lymphoma-2(Bcl-2) in brain tissues, decreasing the expression levels of Aβ_(1-42), p-Tau, IL-6, TNF-α, cysteine aspartate-specific protease 3(caspase-3), cysteine aspartate-specific protease 9(caspase-9), and Bcl-2-associated X protein(Bax), and decreasing the number of activated glial cells in brain tissues. The results of cell experiments showed that esculetin and(+)-lyoniresinol could improve Aβ_(25-35)-induced N9 cell injury. Molecular docking results showed that caffeic acid, trans-p-hydroxy cinnamic acid, isolariciresinol-9'-O-β-D-glucopyranoside, esculetin, and(+)-lyoniresinol had good binding affinity with APP and weak binding affinity with IL-6 and TNF-α. Aqueous extract of Corni Fructus could ameliorate cognitive dysfunction and brain damage in Aβ_(25-35)-induced mice by reducing the number of apoptotic cells and activated glial cells in the brain and decreasing the expression level of inflammatory factors. Caffeic acid, trans-p-hydroxy cinnamic acid, isolariciresinol-9'-O-β-D-glucopyranoside, esculetin, and(+)-lyoniresinol may be the material basis for the anti-AD effect of aqueous extract of Corni Fructus.

Effects and mechanisms of SNP-9 on Aβ25-35-induced damage in bEnd.3 cells / 中国药科大学学报

@#In order to investigate the effects of neuroprotective peptide SNP-9 which is derived from silk fibroin hydrolysate on the injury of the blood-brain barrier in Alzheimer′s disease (AD), Aβ25-35 was used to damage brain microvascular endothelial cells bEnd.3 to establish AD injury model and drug intervention was performed.MTT assay was used to detect the effects of SNP-9 and Aβ25-35 on cell viability.RT-qPCR was used to determine the effects of SNP-9 and Aβ25-35 on the mRNA levels of tight junctions (TJs)-related ZO-1, occludin and claudin-5.Western blot was used to detect the effects of SNP-9 and Aβ25-35 on the protein levels of TNF-α, phosphorylated NF-κB, NF-κB, IκBα and RAGE.The results showed that SNP-9 reduced bEnd.3 cell damage induced by Aβ25-35, and improved the abnormal mRNA levels of ZO-1, occludin and claudin-5 in model cells.It alleviated the abnormal protein levels of TNF-α, phosphorylated NF-κB, IκBα and RAGE induced by Aβ25-35. These results suggest that SNP-9 may regulate the levels of TNF-α in model cells by influencing RAGE/NF-κB pathway, and then ameliorate TJs-related abnormalities and alleviate bEnd.3 cell injury induced by Aβ25-35.

Effects of stachyine on apoptosis in an Aβ-induced PC12 cell model of Alzheimer's disease / 南方医科大学学报

OBJECTIVE@#To investigate the effects of stachydrine (STA) on apoptosis of Aβ-induced PC12 cells mimicking Alzheimer's disease and explore the mechanisms.@*METHODS@#The differential genes of STA were analyzed based on GSE85871 data, and the target genes of STA were identified using STITCH database. PC12 cells were treated with Aβ to establish a cell model of Alzheimer's disease, and the changes in cell viability and cell cycle in response to STA treatment were assessed using MTT assay and flow cytometry, respectively. RT-PCR and Western blotting were used to detect the relevant gene or protein expressions in the treated cells.@*RESULTS@#GSE85871 data showed 37 up-regulated genes and 48 down-regulated genes in cells following treatment with STA. Analysis of the data from the STITCH database indicated that RPS8 and EED were the target genes of STA. Treatment of PC12 cells with Aβ significantly lowered the cell viability ( < 0.05) and the expressions of RPS8 and EED at both the mRNA and protein levels ( < 0.05), and obviously inhibited the expression of apoptosis-related proteins Bcl-2 and p53 ( < 0.05). STA treatment of the cells significantly reversed the effect of Aβ and induced cell cycle arrest in G2/M phase, causing also significantly increases in the expression levels of RPS8, EED, Bcl-2 and p53 ( < 0.05).@*CONCLUSIONS@#STA plays an important role in inhibiting the apoptosis of PC12 cells induced by Aβ possibly by regulating RPS8 and EED expression to promote the expressions of Bcl-2 and p53.

Effect of Naringenin on Oxidative Stress and Tau Protein Phosphorylation of Aβ25-35-induced PC12 Cell Injury / 中国实验方剂学杂志

Objective:To investigate the effects of naringenin on oxidative stress and Tau protein phosphorylation of adrenal pheochromocytoma（PC12） cells injured by β-amyloid（Aβ）25-35 and its relationship with estrogen receptor（ER） and phosphatidylinositol -3 kinase/protein kinase B（PI3K/Akt） signaling pathway. Method:The PC12 cells were intervened with Aβ25-35 to prepare the injury model. The experiment was divided into blank group， model group， naringenin（400，40，4，0.4，0.04，4×10-3，4×10-4，4×10-5 μmol·L-1）group， positive drugs estradiol（E2）（1 nmol·L-1）+Aβ25-35 group， naringenin（0.4，0.04，4×10-3，4×10-4，4×10-5 μmol·L-1）+Aβ25-35 group， E2+Aβ25-35+ER antagonist（ICI182780）（1 μmol·L-1） group， naringenin+Aβ25-35+ICI182780 group， E2+Aβ25-35+PI3K blocker（LY294002）（50 μmol·L-1） group， naringenin+Aβ25-35+LY294002 group. Methye thiazolye telrazlium（MTT）method was used to detect the cell proliferation index， 2'，7'-Dichlorodi -hydrofluorescein diacetate（DCFH-DA） was used as a fluorescent probe to detect the content of reactive osygen species（ROS）， the content of malondialdehyde（MDA） and the activity of superoxide dismutase（SOD） were measured by thiobarbituric acid（TBA） and oxidase methods， Western blot was used to detect the expression of phosphorylated Tau protein/total Tau protein（p-Tau/t-Tau）. Result:According to the results of MTT experiment， 0.4 μmol·L-1 was selected as the best effective concentration of naringenin， compared with the blank group， the cell proliferation index of model group decreased significantly （P<0.01）， compared with model group， the cell proliferation index of naringenin+Aβ25-35 group increased significantly （P<0.01）. In addition， compared with blank group， the content of ROS， MDA and the expression of p-Tau/t-Tau in the model group increased significantly （P<0.01）， and the activity of SOD decreased significantly （P<0.01）， compared with model group， the content of ROS， MDA and the expression of p-Tau/t-Tau in naringenin+Aβ25-35 group decreased significantly （P<0.01）， and the activity of SOD increased significantly （P<0.01）， compared with naringenin+Aβ25-35 group， the addition of ICI182780 and LY294002 significantly reversed the role of naringenin in the above indicators （P<0.01）. The effect of naringenin was similar to that of E2. Conclusion:Naringenin can improve the cell proliferation index and protect PC12 cells from Aβ25-35 injury， which may be achieved by activating ER and PI3K/Akt signaling pathway to reduce ROS， MDA content， p-Tau/t-Tau expression and promote SOD activity.

Neuroprotective Effect of Tetrahydroxy Stilbene Glucoside on Aβ25-35-induced Neuron Synapses via CREB/BDNF Signaling Pathway / 中国实验方剂学杂志

Objective: To investigate the neuroprotective effect and mechanism of tetrahydroxy stilbene glucoside (TSG) on β-amyloid protein 25-35 (Aβ25-35)-induced neuron synapses damage. Method: Primary neurons were isolated and purified from cerebral cortex of suckling mouse. Then neurons were divided into control group, model group (incubation with Aβ25-35) and TSG groups (after incubation with Aβ25-35, add 6.25, 12.5, 25, 50, 100 μmol·L-1 TSG). Cell counting kit-8 (CCK-8) and Lactate dehydrogenase (LDH) methods were used to observe the viability of neuron, immunocytochemical staining was performed to determine the expressions of synapsin-1 (SYN-1), and the concentration of postsynaptic density-95 (PSD-95) and synaptophysin (SYP) were detected by enzyme-linked immunosorbent assay (ELISA) method. The level of cyclic adenosine monophosphate response element binding protein (CREB) and brain-derived neurotrophic factor (BDNF) mRNA were determined by reverse transcription-polymerase chain reaction (RT-PCR) and the level of CREB, Phosphorylated CREB (p-CREB) and BDNF proteins were determined by immunocytochemical staining or Western blot (WB). Result: Compared with normal group, the cell survival rate of model group was significantly reduced, LDH release was significantly increased (PPPPPPP-1,25 μmol·L-1 TSG can significantly enhance the expression of SYN-1(PPPPConclusion: TSG possesses the neuroprotective effect on Aβ25-35-induced neuron synapses, the mechanism may be associated with the activation of CREB/BDNF signaling pathway.

Intervention Effect of Kidney-tonifying and Essence-filling Therapy on Hippocampal Autophagy in Kidney-deficiency Alzheimer Mice / 中国实验方剂学杂志

Objective:To study the effect of Liuwei Dihuangwan on the improvement of autophagy level of hippocampal neurons in mice with kidney deficiency Alzheimer' s disease (AD) and its partial mechanism, in order to explore part of therapeutic mechanisms of kidney-tonifying and essence-filling therapy for AD. Method:Healthy male C57-B6 mice were divided into control group, AD group, kidney deficiency AD group and Liuwei Dihuangwan group(1.08 g·kg-1). The control group and the AD group were subcutaneously injected with normal saline (15 mL·kg-1) daily, and the kidney deficiency AD group and the Liuwei Dihuangwan group were subcutaneously injected with hydrocortisone injection (15 mL·kg-1) daily for 20 consecutive days. On the 21st day, the other three groups were injected with 6 μg amyloid beta protein 25-35(Aβ25-35) in the lateral ventricle, while the control group was injected with sterile saline into the lateral ventricle. The levels of serum cortisol and testosterone in each group were detected by enzyme-linked immunosorbent assay (ELISA), the morphological changes in hippocampal neurons were observed by transmission electron microscopy, the expression of microtubule-associated protein 1 light chain 3 (LC3) was detected by immunofluorescence, and the expression of selective autophagic junction protein (p62) was detected by Western blot. Result:Compared with normal group, serum cortisol and testosterone levels in AD group and kidney deficiency AD group were significantly reduced (PPPPPPPPPConclusion:Kidney-tonifying and essence-filling therapy can protect hippocampal neurons, increase LC3 expression in hippocampal neurons, decrease p62 expression level and increase autophagy level of hippocampal neurons. It has a certain therapeutic effect on kidney-deficiency Alzheimer' s disease.

Epigallocatechin promotes nuclear translocation of Nrf2 to reduce damage of Aβ25-35 in SH-SY5Y cells / 中国药理学通报

Aim To investigate the protective effect of epigallocatechin(EGC) on SH-SY5Y cells induced by Aβ25-35 injury. Methods MTT and LDH assay were employed to investigate the effects of EGC on viability of SH-SY5Y cells. DCFH-DA fluorescent probe was used to detect the intracellular ROS levels, and the activity of SOD, GSH-Px and MDA in cells was measured to investigate the level of oxidative stress in cells. Western blot analysis was used to determine Nrf2, NQ01, HO-1, Prdx6 and Trxl levels in cells. Results SH-SY5Y cells were injured by Aβ25-35 treatment, and the cell viability was significantly reduced. 5, 10 and 20 μmol . L 1 of EGC alleviated Aβ25-35 induced SH-SY5Y cell injury and reduced LDH release. In addition, EGC could reduce the intracellular ROS level induced by Aβ25-35 and inhibit oxidative stress. At the same time, EGC could significantly enhance the expression of Nrf2, NQ01, HO-1, Prdx6 and Trxl after Aβ25-35 injury. Conclusions EGC could inhibit Aβ25-35 -induced SH-SY5Y cell injury, increase the cells antioxidant levels and reduce the neurotoxicity of Aβ25-35 by promoting nuclear translocation of Nrf2.

Cyanidin-3-glucoside inhibits amyloid β₂₅₋₃₅-induced neuronal cell death in cultured rat hippocampal neurons

Increasing evidence implicates changes in [Ca²⁺]i and oxidative stress as causative factors in amyloid beta (Aβ)-induced neuronal cell death. Cyanidin-3-glucoside (C3G), a component of anthocyanin, has been reported to protect against glutamate-induced neuronal cell death by inhibiting Ca²⁺ and Zn²⁺ signaling. The present study aimed to determine whether C3G exerts a protective effect against Aβ₂₅₋₃₅-induced neuronal cell death in cultured rat hippocampal neurons from embryonic day 17 fetal Sprague-Dawley rats using MTT assay for cell survival, and caspase-3 assay and digital imaging methods for Ca²⁺, Zn²⁺, MMP and ROS. Treatment with Aβ25–35 (20 µM) for 48 h induced neuronal cell death in cultured rat pure hippocampal neurons. Treatment with C3G for 48 h significantly increased cell survival. Pretreatment with C3G for 30 min significantly inhibited Aβ₂₅₋₃₅-induced [Zn²⁺]i increases as well as [Ca²⁺]i increases in the cultured rat hippocampal neurons. C3G also significantly inhibited Aβ₂₅₋₃₅-induced mitochondrial depolarization. C3G also blocked the Aβ₂₅₋₃₅-induced formation of ROS. In addition, C3G significantly inhibited the Aβ₂₅₋₃₅-induced activation of caspase-3. These results suggest that cyanidin-3-glucoside protects against amyloid β-induced neuronal cell death by reducing multiple apoptotic signals.

Chemical Constituents of Drynaria fortunei and Their Protective Effects on PC12 Cell / 中国药学杂志

OBJECTIVE: To study the chemical constituents from the rhizome of Drynaria fortunei and the protective effects of them on PC12 cells induced by Aβ25-35. METHODS: The compounds were isolated and purified by silica gel, Sephadex LH-20, ODS column chromatography, and their structures were identified on basis of spectroscopic METHODS:, such as MS and NMR. PC12 cells were treated with Aβ25-35 to establish the Alzheimer' s disease models. The compounds of different concentrations were added into culture medium to detect the protection. MTT assay was used to detect cell vitality and to observe the protective effects of compounds on PC12 cells induced by Aβ25-35. RESULTS: Nine compounds were isolated and identified as naringin(1), neoeriocitrin(2), 5,7-dihydroxychromone-7-neohesperidoside(3), (E)-4-O-β-D-glucopyranosyl caffeic acid(4), kaempferol(5), luteolin(6), protocatechoic acid(7), psoralen(8), and β-sitosterol(9). The cell experiments were performed on the compounds 1-8 and the RESULTS: showed they can promote the proliferation of PC12 cells. The cell vitality increase with concentration rising, and the difference is statistically significant (P<0.05). CONCLUSION: Compounds 1-8 play an important role in protecting Aβ25-35-induced injury in PC12 cells and they are the main active components of Drynaria fortunei in the protection of central nervous function.

Effects of curcumin on expression of caspase-3 , caspase-8 and caspase-9 in PC12 cells induced by Aβ25-35 / 中国病理生理杂志

AIM:To investigate the effects of curcumin on the viability ,the lactate dehydrogenase(LDH)re-lease,the apoptosis,and the activity and the expression levels of caspase-3,caspase-8 and caspase-9 of rat adrenal pheo-chromocytoma PC12 cells induced by β-amyloid protein 25-35(Aβ25-35 ).METHODS:The PC12 cells were treated with Aβ25-35.The viability and LDH release rates were measured by MTT assay and LDH kit ,respectively.The cells were ran-domly divided into blank control group ,model group,curcumin 10μmol/L group and curcumin 20μmol/L group.The ap-optotic rates were evaluated by flow cytometry with Annexin V-FITC/PI staining.The activities and expression levels of caspase-3,caspase-8 and caspase-9 were detected by colorimetric method and Western blot analysis.RESULTS:Com-pared with model group ,curcumin significantly increased the viability ,and decreased the LDH release rates and the apop-totic rates of the PC12 cells treated with Aβ25-35(P<0.01).Compared with model group,curcumin significantly decreased the activity and expression levels of caspase-3,caspase-8 and caspase-9(P<0.05 or P<0.01).CONCLUSION:Cur-cumin inhibits Aβ25-35-induced apoptosis of PC12 cells by inhibiting the expression of caspase-3,caspase-8 and caspase-9.

Lychee seed saponins improve cognitive function and ameliorate hippocampal neuronal injury in Alzheimer disease rat model induced by Aβ25-35 through AKT/GSK3β pathway / 中国药理学与毒理学杂志

OBJECTIVE Lychee seed, a famous traditional Chinese medicine, recently were reported to improve the learning and memory abilities in mice. However, it is still unclear whether lychee seed saponins (LSS) can improve the cognitive function and associated mechanisms. METHODS In present studies, we established the Alzheimer disease (AD) model by injecting Aβ25-35 into the lateral ventricle of rats. Then the spatial learning and memory abilities of LSS- treated rats were evaluated with the Morris water maze, meanwhile the protein expressions of AKT, GSK3β and Tau in the hippo?campal neuron were analyzed by immunohistochemistry and Western blotting. RESULTS The results showed LSS can improve the cognitive functions of AD rats through shortening the escape latency, increasing the number across the platform, platform quadrant dwell time and the percentage of the total distance run platform quadrant. The protein expression of AKT was significantly up-regulated and that of GSK3β and Tau were decreased remarkably in the hippocampal CA1 area. CONCLUSION Our study is the first to show that LSS significantly improve the cognitive function and prevent hippocampal neuronal injury of the rats with AD by activation of the PI3K/AKT/GSK3β signaling pathway, suggesting LSS may be developed into the nutrient supplement for the treatment of AD.

Effect of Epimedium brevicormon on Aβ25-35 induced SH-SY5Y cells injury / 中草药

Objective: To compare the neuroprotective effect of different elution fractions and compounds of Epimedium brevicormon on SH-SY5Y cells injury induced by Aβ25-35 so as to screen pharmacologically fraction and compounds. Methods: The isolation and purification of extract from E. brevicormon were performed on D101 macroporous resin column chromatography, silica gel column chromatography, Sephadex LH-20 column chromatography, and preparative liquid chromatography. Hoechst 33342/PI double staining method was used to screen neuroprotective fractions and components. Results: Compared to model group, all fractions and kaempferol-3-O-[α-L-rhamnopyranosyl (1→6)-β-D-galactoside]-7-O-α-L-rhamnopyranoside, icariin, epimedin A, and epimedin B from E. brevicormon could significantly increase the cells viability, except of 95% ethanol fraction. Conclusion: E. brevicormon show some protective effect against Aβ25-35 induced SH-SY5Y cells injury. The CH2CI2-MeOH (5:1) extract from E. brevicormon has the most pharmacologically activity, followed by 30% ethanol and 50% ethanol extracts from E. brevicormon.

Effects of butylphthalide on cognitive ability and mitochondrial function in dementia model rats / 西安交通大学学报(医学版)

Objective To explore the protective effects of butylphthalide against Aβ25-35 induced dementia-like pathological rat model and reveal the mechanism.Methods Rats were divided into five groups:control group, model group and NBP groups (10,30,and 100 mg/kg).In model group and butylphthalide groups,Aβ25-35 was injected into the lateral ventricle,while the rats in intervention group were administered with butylphthalide (gastric infusion dose of 2.5 mL/kg).Learning and memory abilities of the rats were observed with water maze test. Mitochondrial function in brain tissue was observed by ATP assay,and the mitochondrial related enzyme activities were detected by the kit.Results Water maze test showed that learning and memory abilities of model group were poorer than those of control group.They were significantly improved in NBP 10 mg/kg group and 30 mg/kg group (P <0.05),but did not change significantly in 100 mg/kg group.Compared with control group,model group had significantly decreased ATP level (P < 0.05 ); cytochrome c oxidase, pyruvate dehydrogenase complex and ketoglutarate dehydrogenase activities were also significantly decreased (P < 0.05 ).Compared with model group, butylphthalide group had significantly improved activities of mitochondrial enzymes that improved mitochondrial function.Conclusion Butylphthalide can improve learning and memory abilities of rats with Aβ25-35 -induced dementia by improving mitochondrial function.

Effects of butylphthalide on cognitive ability and mitochondrial function in dementia model rats / 西安交通大学学报(医学版)

Objective To explore the protective effects of butylphthalide against Aβ25-35 induced dementia-like pathological rat model and reveal the mechanism.Methods Rats were divided into five groups:control group, model group and NBP groups (10,30,and 100 mg/kg).In model group and butylphthalide groups,Aβ25-35 was injected into the lateral ventricle,while the rats in intervention group were administered with butylphthalide (gastric infusion dose of 2.5 mL/kg).Learning and memory abilities of the rats were observed with water maze test. Mitochondrial function in brain tissue was observed by ATP assay,and the mitochondrial related enzyme activities were detected by the kit.Results Water maze test showed that learning and memory abilities of model group were poorer than those of control group.They were significantly improved in NBP 10 mg/kg group and 30 mg/kg group (P <0.05),but did not change significantly in 100 mg/kg group.Compared with control group,model group had significantly decreased ATP level (P < 0.05 ); cytochrome c oxidase, pyruvate dehydrogenase complex and ketoglutarate dehydrogenase activities were also significantly decreased (P < 0.05 ).Compared with model group, butylphthalide group had significantly improved activities of mitochondrial enzymes that improved mitochondrial function.Conclusion Butylphthalide can improve learning and memory abilities of rats with Aβ25-35 -induced dementia by improving mitochondrial function.

Protective Effect and Mechanism of Human Lipoxin A4 on N2a Cell Injury Induced by β-Amyloid Protein 25-35 / 中国药师

Objective: To investigate the protective effect of human lipoxin A4 (LXA4) on N2a cell damage induced by β-amyloid protein 25-35 (Aβ25-35) and the underlying mechanism. Methods: Aβ25-35 was used to treat N2a cells to establish Alzheimer's disease (AD) cell injury model. Meanwhile, LXA4 was added to the experimental group at different concentrations (50, 100 and 200 nmol·L-1 ). MTT assay was used to detect the activity of N2a cells. The apoptosis was detected by Hoechst 33258-PI staining, the expression of P62 and TRAF6 mRNA was detected by RT-PCR, and the expression of P62 and TRAF6 protein was detected by Western blot. Results: Compared with that of the model group, the cell survival rate of LXA4 protective group (50,100 and 200 nmol·L-1 ) increased (P <0. 01) and the apoptosis of N2a cells induced by Aβ25-35 was reduced by LXA4 (100 and 200 nmol·L-1 ) . Compared with that of the model group, the expression of P62-mRNA and protein-P62 of N2a cells treated with Aβ25-35 increased (P <0. 05 or P <0. 01) and the expression of TRAF6-mRNA and protein-TRAF6 of N2a cells treated with Aβ25-35 were reduced (P <0. 05 or P <0. 01). Conclusion: LXA4 has protective effect on N2a cell damage induced by Aβ25-35 , and its mechanism may be related to the up-regulation of P62 gene and down-regulation of TRAF6 gene.

Aβ25-35 protein in different concentrations to create a rat model resembling Alzheimer's disease and the differences in their learning and memory ability / 中国比较医学杂志

Objective To observe the learning and memory ability of rats after injection of Aβ25-35 protein in different concentrations into the lateral ventricle assessed by Morris water maze test, and to explore the optimal concentration of Aβ25-35 in the preparation of AD model rats.Methods Male SD rats were randomly divided into sham operated group and model group.The rats of model group received Aβ25-35 injection in concentrations of 2 μg/μL, 4 μg/μL and 8 μg/μL, respectively.According to the Rat Brain Stereotaxic Atlas, 5 μL of aggregation of Aβ25-35 was injected into the right lateral ventricle to establish the AD rat model.7 days after successful modeling, Morris water maze was used to test thechanges of learning and memory ability of the rats.Results There was no significant difference in the average swimming speed between the two groups (P > 0.05).The escape latency time of rats in the model group was significantly increasedcompared with the sham group (P 0.05).The activity time and distance of target quadrant of the rats injected with different concentration of Aβ25-35in the model group were significantly reduced compared with the sham group (P 0.05).Compared with the sham-operated group, the number of platform-crossing of rats injected with different doses of Aβ25-35in the model group were significantly reduced (P 0.05).Conclusions The recommended dose and concentration of Aβ25-35 to be injected into the unilateral ventricle to establisha rat model of Alzheimer's disease is 4 μg/μL in a volume of 5 μL.

Protection of 20 Chinese materia medica extracts to Aβ25-35-induced SH-SY5Y cell injury using high content screening / 中草药

Objective: To identify neuroprotective extracts with the protective effects on Aβ25-35-induced SH-SY5Y cell injury via high content screening (HCS). Methods: Hoechst 33342/PI double staining method was used to screen neuroprotective extracts from 60 Chinese materia medica (CMM) extracts. Further more, the effects of neuroprotective extracts on Aβ25-35-induced changes in the levels of Caspase-3/7 were detected. Results: The results showed that 17 extracts had obviously neuroprotective effects. Among the 17 extracts, 8 of them inhibited Aβ25-35-induced up-regulation of Caspase-3/7. Conclusion: HCS is an efficient method to screen neuroprotective extracts with the protective effects of Aβ25-35-induced SH-SY5Y cell injury. The neuroprotective extracts have potential medicinal value in Alzheimer's disease.

Scutellaria barbata flavonoids inhibits NFT aggregation and regulatory mechanism in rats induced by composited Aβ / 中国病理生理杂志

AIM: To investigate the effects of Scutellaria barbata flavonoids (SBF) on neurofibrillary tangle (NFT) aggregation, tau protein phosphorylation and the regulated mechanism of glycogen synthase kinase (GSK) 3βand protein phosphatase (PP) 2A in the rats induced by amyloid βprotein 25-35 (Aβ25-35) in combination with AlCl3 and re-combinant human transforming growth factor ( RHTGF)-β1( composited Aβ) .METHODS:The male SD rats were used to establish the simulated Alzheimer disease ( AD) model by intracerebroventricular injection of composited Aβ.The Morris water maze was applied for screening the successful model rats with learning and memory deficits .The successful model rats were daily and orally administrated with SBF at doses of 35, 70 and 140 mg/kg or positive control drug Ginkgo biloba leaves flavonoids ( GLF) at 140 mg/kg for 37 d.The silver nitrate staining was used to determine the cortical NFT .The protein levels of total tau, phosphorylated protein of tau at Ser199 and Ser214 sites, GSK3βand PP2A in hippocampus and cortex were determined by Western blot .The mRNA expression of GSK3βand PP2A in the hippocampus and cortex was detected by RT-PCR.RESULTS:Compared with sham group , the cell number of positive NFT with silver nitrate staining in model rat cerebral cortex was significantly increased .The protein levels of phosphorylated tau protein at Ser 199 and Ser214 sites, GSK3βin the hippocampus and cerebral cortex in the model rats dramatically elevated , and PP2A was marked decreased as compared with the sham group rats.Meanwhile, the mRNA expression of GSK-3βsignificantly increased but PP2A was de-creased.However, these above abnormalities were differently attenuated by treating with SBF at different doses or GLF at 140 mg/kg for 37 d.CONCLUSION: SBF suppresses the NFT aggregation by inhibition of the regulatory functions of GSK-3βand PP2A, thus reducing the phosphorylation of tau protein .

Neuroprotective effect of peptides extracted from walnut (Juglans Sigilata Dode) proteins on Aβ25-35-induced memory impairment in mice / 华中科技大学学报（医学）（英德文版）

Alzheimer's disease (AD) is one of the major neurodegenerative disorders of the elderly, which is characterized by the accumulation and deposition of amyloid-beta (Aβ) peptide in human brains. Oxidative stress and neuroinflammation induced by Aβ in brain are increasingly considered to be responsible for the pathogenesis of AD. The present study aimed to determine the protective effects of walnut peptides against the neurotoxicity induced by Aβ25-35 in vivo. Briefly, the AD model was induced by injecting Aβ25-35 into bilateral hippocampi of mice. The animals were treated with distilled water or walnut peptides (200, 400 and 800 mg/kg, p.o.) for five consecutive weeks. Spatial learning and memory abilities of mice were investigated by Morris water maze test and step-down avoidance test. To further explore the underlying mechanisms of the neuroprotectivity of walnut peptides, the activities of superoxide dismutase (SOD), glutathione (GSH), acetylcholine esterase (AChE), and the content of malondialdehyde (MDA) as well as the level of nitric oxide (NO) in the hippocampus of mice were measured by spectrophotometric method. In addition, the levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β) and IL-6 in the samples were determined using ELISA. The hippocampal expressions of inducible nitric oxide synthase (iNOS) and nuclear factor κB (NF-κB) were evaluated by Western blot analysis. The results showed that walnut peptides supplementation effectively ameliorated the cognitive deficits and memory impairment of mice. Meanwhile, our study also revealed effective restoration of levels of antioxidant enzymes as well as inflammatory mediators with supplementation of walnut peptides (400 or 800 mg/kg). All the above findings suggested that walnut peptides may have a protective effect on AD by reducing inflammatory responses and modulating antioxidant system.

Genistein protects PC12 cells from Aβ(25-35)-induced apoptosis via JNK signaling and regulation of Fas pathway / 中国药理学通报

Aim To investigate the effect of genistein ( GEN) against Aβ( 25 -35 )-induced PC12 cells in regulation of Fas pathway through the activation of JNK. Methods Aβ( 25 -35 )-induced PC12 cells model was established. MTT and fluorescence activated cell sorting to analyze cell viability and apoptotic rate. Fluorescence quantitative PCR was used to detect Fas apoptotic pathways related gene Fas, FasL, caspase-3 and caspase-8 mRNA relative expression. Spectropho-tometry was used to detect caspase-3 and caspase-8 en-zyme activity. Western blot was adopted to detect JNK and p-JNK protein expression level changes. Results GEN attenuated Aβ( 25-35 )-induced upregulation of Fas and FasL, caspase-3 and caspase-8 mRNA lev-el, caspase-3 and caspase-8 enzyme activity, and sig-nificantly reduced Aβ(25-35) induced JNK phospho-rylation level. Conclusion GEN can protect PC12 cells from Aβ(25-35)-induced apoptosis via reducing Aβ( 25 -35 )-induced phosphorylation of JNK activa-tion, and then inhibit the JNK dependent Fas apoptotic pathway.