The risk of Alzheimer′s disease transmitted by blood transfusion based on APP/PS1 double transgenic mice / 中国输血杂志

【Objective】 To explore the risk of Alzheimer′s disease (AD) transmitted by blood transfusion. 【Methods】 There were 10 APP/PS1 mice of 3, 6 and 9 months old, half female and half male, and the cognitive and behavioral abilities of C57 mice of the same age were measured, and the blood of the oldest APP/PS1 mice with no behavioral changes were collected to detect the contents of Aβ40 and Aβ42. The polymers Aβ40 and Aβ42 were prepared and Western blotting analysis was conducted. Kunming mice aged from 6 to 7 months were randomly divided into 6 groups (10 mice/ group, half male and half female). The blood of APP/PS1 mice was injected intravenously in experimental group 1-2(100 μL/mouse) with high frequency injection (3 times/week) and low frequency injection (1 time/week), respectively. In experimental group 3-4, Aβ40 and Aβ42 polymerized mixture (100 μL/mouse) were injected in high frequency and low frequency, respectively. The control group 1-2 was injected with the same amount of normal saline, with high frequency and low frequency, respectively. The above groups were injected for 4 weeks, and the cognitive and behavioral abilities were tested and analyzed one week after injection. Finally, the contents of Aβ40 and Aβ42 in blood of Kunming mice were detected. 【Results】 Change in cognitive and behavioral ability showed in 9 months old APP/PS1 mice, but not in 3 and 6 months old APP/PS1 mice. The contents of Aβ40 and Aβ42 (pg/mL) in blood of 6-7 months old APP/PS1 mice were 418.40±2.18 and 15.68±0.20, respectively. Except for monomers, most of the polymerized mixtures of Aβ40 and Aβ42 were dimers and trimers. In both high frequency and low frequency, Kunming mice transfused with blood of APP/PS1 mice (experimental group 1-2) showed a certain degree of anxiety-like behavior and short-term memory shortening in open-field test and conditioned fear test, but without significant difference. There was no significant difference in open field test, new object recognition, Barnes maze and cognitive behavior analysis of conditioned fear between experimental group 3-4 and the control group. The levels of blood Aβ40 and Aβ42(pg/mL) of Kunming mice detected by ELISA were 10.30±0.08 and 3.360±0.005, respectively, and there was no significant difference between the two groups. 【Conclusion】 Blood transfusion of APP/PS1 mice and the mixture of Aβ40 and Aβ42 have no significant effect on the cognitive function of healthy Kunming mice in a short time, and the risk of AD transmission is relatively low.

Effects of pranlinide on cognitive behavior, β amyloid protein 6E10, inflammatory factors and neuronal cell morphology in brain and retina of 5×FAD mice and WT mice / 解剖学报

[Abstract] Objective To study the effects of pranlinide on cognitive behavior, β amyloid(Aβ) protein 6E10, inflammatory factors and neuronal cell morphology in brain and retina of 5×FAD mice and WT mice. Methods Thirty two 5×FAD mice and 16 WT mice were selected. All were female. 5×FAD mice were randomly divided into blank group and treatment group; No treatment was given in WT group. Blank group was intraperitoneally injected with PBS; treatment group was received intraperitoneal injection of pranlinide once a day for 8 weeks. The changes of cognitive ability were measured by Morris water maze test. The expression of Aβ6E10 protein in mice hippocampal cells and retina was detected by immunohistochemistry. Tumor necrosis factor α(NF-α) was determined by enzyme-linked immunosorbent assay. The same method was also used for interleukin-1β(IL-1β) detection (The content of inflammatory factors). The arrangement and morphology of nerve cells in mouse hippocampal tissue were determined by hematoxylin-eosin (HE) staining. Results The latency time of treatment group was shorter than that of 5×FAD group,and the times of crossing the platform and the percentage of target quadrant stay in the treatment group were higher than those in the 5×FAD group, and the differences were statistically significant (P0. 05). Compared with the 5×FAD group, the nerve cells in the treatment group were arramged in order and clear relatively. The distribution of glial cells was concentrated; The surrounding clearance was small. Conclusion Pranlinide can improve the cognitive ability of mice. The arrangement of nerve cells is regular, the shape is regular and the boundary is clear; The distribution of glial cells is concentrated; surrounding of clearance decrease. Aβ6E10 is synchronized in brain and retina.

Pay attention to the diagnosis and treatment of cerebral amyloid angiopathy-related inflammation / 中华神经科杂志

Cerebral amyloid angiopathy-related inflammation is an inflammatory reaction process caused by beta-amyloid protein deposited in the cortical and leptomeningeal vessels, which is a rare type of cerebral amyloid angiopathy. Most of the patients are middle-aged and elderly, and manifest as progressive cognitive impairment, headache, seizures, and focal neurological deficits. Brain magnetic resonance imaging shows asymmetric T 2/fluid attenuated inversion recovery hyperintensity in cortical and subcortical white matter, in addition to multiple cerebral microbleeds. The disease often needs to be differentiated from primary angiitis of the central nervous system, glioma, and varicella-zoster virus encephalitis. Although the disease is rare, prompt treatment with glucocorticoids and immune suppressants can reduce death and disability and significantly improve outcome. Therefore, it is necessary to improve the ability of early diagnosis and treatment of this disease.

Effect of Aloe-emodin on Aβ42 Aggregation and Cytotoxicity in Presence of Al3+ / 中国实验方剂学杂志

ObjectiveTo study the inhibitory effect of aloe-emodin （AE） on aluminum ion （Al3+）-induced β-amyloid protein 42 （Aβ42） aggregation and its depolymerization on formed Aβ42-Al3+ aggregates in vitro， and to investigate the effect of AE on the cytotoxicity of Aβ42 aggregation in the presence of Al3+. MethodThe Aβ42 group， Aβ42+Al3+ group， Aβ42+AE group， Aβ42+Al3++AE group and the depolymerization test group were set up in the experiment. The aggregation fibrosis process， aggregation morphology， aggregation size and cytotoxicity of Aβ42 in each group were detected by thioflavin T （ThT） fluorescence assay， transmission electron microscopy （TEM）， dynamic light scattering （DLS） experiment and thiazolyl blue （MTT） cytotoxicity assay. ResultCompared with the Aβ42 group， Al3+ could promote Aβ42 aggregation， increase the fluorescence intensity of ThT by 124.48%， induce the aggregation of Aβ42 to form fiber bundles with larger particle size， and significantly reduce the cell viability of human neuroblastoma SH-SY5Y cells （P<0.01）， thus reducing the cell survival rate to 51.05%. AE not only inhibited Aβ42 aggregation， but also inhibited Al3+-induced Aβ42 aggregation in a concentration-dependent manner. Compared with the Aβ42+Al3+ group， high concentration of AE could reduce the ThT fluorescence intensity to 41.66%， and change the polypeptide aggregation pathway to form amorphous aggregates with small particle size. Besides， it significantly inhibited the cytotoxicity of Aβ42 induced by Al3+ （P<0.01）， and restored the cell survival rate to 84.87%. Further depolymerization was conducted， AE could depolymerize Aβ42-Al3+ aggregates to make the formed aggregates disappear and form some small-particle short fibers and amorphous structure aggregates with low toxicity. ConclusionAE can inhibit Aβ42 aggregation and cytotoxicity in the presence of Al3+， depolymerize the formed Aβ42-Al3+ aggregates and alleviate the cytotoxicity， thus laying the foundation for exploring the mechanism of AE in the treatment of Alzheimer's disease.

Effect of Aloe-emodin on Aβ42 Aggregation and Cytotoxicity in Presence of Al3+ / 中国实验方剂学杂志

ObjectiveTo study the inhibitory effect of aloe-emodin （AE） on aluminum ion （Al3+）-induced β-amyloid protein 42 （Aβ42） aggregation and its depolymerization on formed Aβ42-Al3+ aggregates in vitro， and to investigate the effect of AE on the cytotoxicity of Aβ42 aggregation in the presence of Al3+. MethodThe Aβ42 group， Aβ42+Al3+ group， Aβ42+AE group， Aβ42+Al3++AE group and the depolymerization test group were set up in the experiment. The aggregation fibrosis process， aggregation morphology， aggregation size and cytotoxicity of Aβ42 in each group were detected by thioflavin T （ThT） fluorescence assay， transmission electron microscopy （TEM）， dynamic light scattering （DLS） experiment and thiazolyl blue （MTT） cytotoxicity assay. ResultCompared with the Aβ42 group， Al3+ could promote Aβ42 aggregation， increase the fluorescence intensity of ThT by 124.48%， induce the aggregation of Aβ42 to form fiber bundles with larger particle size， and significantly reduce the cell viability of human neuroblastoma SH-SY5Y cells （P<0.01）， thus reducing the cell survival rate to 51.05%. AE not only inhibited Aβ42 aggregation， but also inhibited Al3+-induced Aβ42 aggregation in a concentration-dependent manner. Compared with the Aβ42+Al3+ group， high concentration of AE could reduce the ThT fluorescence intensity to 41.66%， and change the polypeptide aggregation pathway to form amorphous aggregates with small particle size. Besides， it significantly inhibited the cytotoxicity of Aβ42 induced by Al3+ （P<0.01）， and restored the cell survival rate to 84.87%. Further depolymerization was conducted， AE could depolymerize Aβ42-Al3+ aggregates to make the formed aggregates disappear and form some small-particle short fibers and amorphous structure aggregates with low toxicity. ConclusionAE can inhibit Aβ42 aggregation and cytotoxicity in the presence of Al3+， depolymerize the formed Aβ42-Al3+ aggregates and alleviate the cytotoxicity， thus laying the foundation for exploring the mechanism of AE in the treatment of Alzheimer's disease.

Abdominal acupoint thread embedding therapy based on "brain-intestinal connection" for mild-to-moderate Alzheimer's disease and its effects on serum levels of APP and Aβ / 中国针灸

OBJECTIVE@#To compare the clinical efficacy of abdominal acupoint thread embedding therapy based on "brain-intestinal connection" combined with donepezil hydrochloride tablets and oral donepezil hydrochloride tablets alone for mild-to-moderate Alzheimer's disease (AD) and observe its effects on amyloid precursor protein (APP) and β-amyloid protein@*METHODS@#Sixty patients with AD were randomly divided into an observation group (30 cases, 3 cases dropped off) and a control group (30 cases, 3 cases dropped off). The patients in the control group were treated with donepezil hydrochloride tablets (5 mg per day); based on the treatment in the control group, the patients in the observation group were treated with abdominal acupoint thread embedding therapy at Zhongwan (CV 12), Xiawan (CV 10), Huaroumen (ST 24), Wailing (ST 26), Daheng (SP 15), etc., once every 10 days. Both groups were treated for 2 months. The mini-mental state examination (MMSE), Alzheimer's disease assessment scale-cognitive subscale (ADAS-Cog), activity of daily living scale (ADL), neuropsychiatric inventory questionnaire (NPI) as well as the serum levels of APP and Aβ@*RESULTS@#After treatment, the MMSE scores in the two groups were higher than those before treatment (@*CONCLUSION@#The abdominal acupoint thread embedding therapy based on the theory of "brain-intestinal connection" combined with donepezil hydrochloride tablets can improve cognitive function, self-care ability of daily life and mental behavior, and reduce the serum levels of APP and Aβ

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.

Mechanisms of electroacupuncture for improving Alzheimer's disease from reducing β amyloid protein level / 针刺研究

Alzheimer's disease (AD), a neurodegenerative disorder characterized by amyloid deposits and neurofibrillary degeneration, is the most common type of dementia and has no incurable therapies at the moment. Electroacupuncture (EA) therapy has been widely used in clinical treatment of AD, and has attained approving effects. This article reviews the development of researches on the mechanisms of EA underlying improving AD by diminishing β amyloid protein （Aβ） neurotoxicity, from 1) up-regulating hippocampal cellular autophagy, 2) improving cerebral energy metabolism by activating oxidation stress-related factors peroxisome proliferator-activated receptor γ coactivator 1 alpha and sirtuin 1 in the hippocampus and frontal cerebral cortex, 3) relieving inflammatory reaction by lowering expression of tumor necrosis factor-alpha and high-mobility group box 1 and increasing expression of Interleukin 10, and 4) promoting degradation of Aβ1-42 by down-regulating expression of insulin degeneration enzyme, lipoprotein, transthyretin, apolipoprotein and α2 mcroglobulin. Meanwhile, a comprehensive clinical therapy of AD is proposed.

Study on the Mechanism of Sinapic Acid against PC 12 Cell Injury Induced by Aβ1-42 Based on PI 3K/Akt/GSK3β Signaling Pathway / 中国药房

OBJECTIVE：To investigate the mechanism of sinapic acid （SA）against PC 12 cell injury induced by Amyloid β1-42 protein（Aβ1-42）based on PI 3K/Akt/GSK3β signaling pathway. METHODS：PC12 cells of rats were randomly divided into control group，Aβ group（Aβ1-42 2 μmol/L），Aβ+SA group（Aβ1-42 2 μmol/L+SA100 μmol/L），Aβ+SA+LY group [Aβ1-42 2 μmol/L+SA 100 μmol/L+LY294002（PI3K inhibitor ）10 μmol/L]，Aβ+LY group（Aβ1-42 2 μmol/L+LY294002 10 μmol/L）and LY group （LY294002 10 μmol/L）. Except for control group and LY group ，the cells of other groups were replicated the damage model with Aβ1-42. After 24 hours of culture ，the morphology of cells was obsened in each group with a microscope ，and MTT assay was adopted to determine the cell viability of PC 12 cells in each group. Western blotting assay was used to detect the expression of PI 3K，p-PI3K， Akt，p-Akt，GSK3β and p-GSK3β in cells of each group. RESULTS：Compared with control group ，the number of cells decreased and some synaptic breaks disappeared in Aβ group while cell viability，ratio of p-PI 3K/PI3K，p-Akt/Akt and p-GSK 3β/GSK3β in Aβ group were decreased significantly（P＜0.05 or P＜0.01）. Compared with Aβ group，the cells became round and synapses became more in Aβ+SA group while cell viability，the ratio of p-PI 3K/PI3K，p-Akt/Akt and p-GSK 3β/GSK3β were increased significantly（P＜0.05）. Compared with Aβ+SA group，some synaptic breaks occurred in Aβ+SA+LY group while cell viability， the ratio of p-PI 3K/PI3K，p-Akt/Akt and p-GSK 3β/GSK3β were decreased significantly（P＜0.05）；Aβ+LY group had more cell debris，and t he cell viability was decreased ，but the difference was not significant ，and the ratio of p-PI 3K/PI3K，p-Akt/Akt and p-GSK3 β/GSK3 β had no significant change （P＞0.05）; LY294002 alone had no significant effect on morphology ，cellviability and the ratio of p-PI 3K/PI3K，p-Akt/Akt or p-GSK 3β/ GSK3 β （P＞0.05）. CONCLUSIONS ： SA may play aprotective role against PC 12 cell injury induced by A β 1-42 through activating PI 3K/Akt/GSK-3β.

Clinical value of Aβ1-42, tau protein and thyroid hormone levels in predicting cognitive impairment after ischemic stroke / 中国神经精神疾病杂志

Objective To investigate the relationship between serum markers β amyloid (Aβ), tau and thyroid hormone levels and post-stroke cognitive impairment (PSCI) in the acute phase of cerebral infarction. Methods A total of 214 patients with acute cerebral infarction were enrolled. The baseline data and serological indicators were collected and the cognitive function of patients was evaluated. All patients were divided into cognitive impairment group and normal group based on follow-up results. The differences of Aβ1-42, tau protein and thyroxine levels between the two groups and their relationship with disease progression were analyzed. The Cox regression analysis and ROC curve were used to compare the above parameters to predict the development of PSCI. Results The total protein level of Tau (210.6 ±98.9 pg/mL) was higher and Aβ1-42 (426.1 ±123.5 pg/mL) and triiodothyronine (T3) (1.43 ±0.57 nmol/L), free thyroxine (FT4) (13.15±2.23 pmol/L) was significantly lower in the cognitive impairment group than in the normal group (P<0.05). Tau protein (r=-0.457), Aβ1-42 (r=0.348), T3 (r=0.211), and FT4 (r=0.306) were all associated with disease progression (P<0.05). Cox regression analysis showed that Aβ1-42 and T3 were important influencing factors in the occurrence of PSCI. The area under the curve of Aβ1-42 combined with T3 was 0.841. The specificity and the sensitivity were 74.8% and 85.3%, respectively, with a diagnostic cutoff value of 0.572. Conclusion Aβ1-42 and T3 levels in the acute phase of cerebral infarction may predict the progression of PSCI.

Application of PET/CT imaging in early diagnosis of Alzheimer disease / 中国医学影像技术

Alzheimer disease (AD) is a common neurodegenerative disorder in the elderly. It is the most common cause of dementia and is difficult to diagnose in the early stage. PET imaging has important value for early diagnosis, and amyloid imaging is the best choice for early diagnosis of AD, glucose imaging has great value of assessment of disease condition. The application and progresses of PET imaging in early diagnosis of AD, focusing on glucose imaging, amyloid protein imaging and tau protein imaging were reviewed in this article.

Effect of Ferulic Acid on Learning and Memory Impairment by the Repairing of Mitochondrial Fission-Fusion Imbalance in AD Mice / 中国药学杂志

OBJECTIVE: To discuss the effect of ferulic acid(FA) on learning and memory impairment and neuron protection by repairing the imbalance of mitochondrial fission-fusion dynamics in Alzheimer′s disease (AD) mice. METHODS: The KM mice were randomly divided into normal control group (A group, n=10), model group (B group, n=10), positive control group (huperzine A tablets, C group, n=10) and low dose of FA group (D-low group, n=10), high dose of FA group (D-high group, n=10). Mice in B, C, D-low and D-high groups were built as AD model by injecting Aβ1-42 into the lateral ventricle. The learning and memory ability of mice were detected by Morris water maze test. The mRNA of dynamin-related protein 1 (Drp1) were detected by PCR. The AD related pathological proteins and mitochondrial fission-fusion proteins were detected by Western blot. The content and distribution of Aβ was analyzed using immunofluorescence staining. RESULTS: ①The escape latency of mice in D-high group was shorter than B group, but a little longer than A group (P0.05). ②The mean expressions of Drp1, CaN subunit α (CnAα), CnAβ mRNA in D-high group were lower than B group, but higher than A group (P<0.05). ③The mean expressions of amyloid precursor protein (APP), beta-site APP cleaving enzyme 1 (Bace1), Tau46 and pS396 proteins in D-high group were lower than B group, but higher than A group (P<0.05).The mean expressions of Drp1Ser637, CnAα, protein kinase A catalytic subunit c (PKAc), mitofusin gene 2(Mfn2) proteins in D-high group were basically identical with A group. ⑤The levels of Aβ formation and accumulation in mice cortex and hippocampus of D-high group were less than B group. CONCLUSION: It′s suggested that ferulic acid(FA) might repair pathological damage of Alzheimer′s disease by improving the imbalance of mitochondrial fission-fusion dynamics.

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.

Relationship between BDNF and TRPC3 in a Rat Model of Alzheimer's Disease Induced by β-amyloid Protein / 中国医科大学学报

Objective To investigate the expression and relationship of canonical transient receptor potential channel-3 (TRPC3) and brain-derived neurotrophic factor (BDNF) in the hippocampus of a rat model of Alzheimer's disease (AD). Methods SD rats were randomly divided into PBS, AD, and AD+BDNF experimental groups. AD models were generated by intracerebroventricular injection ofβ-amyloid protein (Aβ1-42). BDNF was injected via the lateral ventricle catheter after 14 days. The Morris water maze test was used to assess the spatial learning and memory ability of the rats. The expression of TRPC3 and BDNF mRNA and protein in the hippocampus were detected by RT-PCR and Western blotting, respectively. Results The Morris water maze test showed that the escape latencies of the fifth day in the AD group were longer than those in the PBS group (P ＜ 0. 05). The escape latencies in the AD+BDNF group were shorter than those in the AD group (P ＜ 0. 05). RT-PCR and Western blotting results showed that the expression of both TRPC3 and BDNF were reduced in the AD group compared with the PBS group (P ＜ 0. 05). TRPC3 expression was increased in the AD+BDNF group compared with the AD group (P ＜ 0. 05). Conclusion The expression of BDNF and TRPC3 is decreased in the hippocampus of AD rats. An exogenous BDNF injection appears to improve the spatial learning and memory of AD rats that are impaired by a Aβ1-42 injection, possibly via TRPC3 upregulation, and may play a protective role in neurons.

Brain histopathological changes in WHBE rabbits fed with high cholesterol diet plus copper drinking water / 中国实验动物学报

Objective To observe the pathological changes of brain tissues in the WHBE rabbit model of sporadic Alzheimer disease (AD). Methods Thirty 3 -4-month old male WHBE rabbits were randomly divided into 3 groups:normal control (NC) group, high cholesterol diet (HCD) group, high cholesterol diet + copper drinking water ( HCD+ Cu2+) group, 10 in each group. Another 10 senile (36-48-month old) male WHBE rabbits were taken as senile group. The NC group and the senile group were fed a normal basic diet, the HCD group fed a 2% cholesterol diet, and the HCD+Cu2+group fed a 2% cholesterol diet plus 0. 12 PPM copper drinking water for 12 weeks. The levels of total cholesterol (TC) and β-amyloid protein (Aβ) 1-42 were measured at 12 weeks. The activity of superoxide dismutase ( SOD) and the content of malondialdehyde (MDA) in the cortex and the hippocampus were detected. In addition, the covered area of Aβ, β-site APP cleaving enzyme 1(BACE1) and phosphorylated tau (p-tau) protein in coronal sections of brain tissues were also observed by immunohistochemical staining. The senile plaques and the neurofibrillary tangles were observed by Congo red and Bielschowsky staining, respectively. Results The body weight of WHBE rabbits in the senile group was significantly higher than that of the NC group ( P ＜ 0. 01 ), and the plasma TC and Aβ1 -42 in each group were significantly higher than that in the NC group (P ＜ 0.05, P ＜ 0.01). The activity of SOD in brain tissues was significantly lower than that of NC group (P＜ 0. 05), and the MDA content was significantly higher than that of NC group (P＜ 0. 05, P ＜ 0. 01). Immunohistochemical staining showed that the covered area of Aβ, BACE1 and p-tau in brain tissues of all groups were significantly higher than that of NC group (P ＜ 0. 05, P ＜ 0. 01), and the covered area of BACE1 and p-tau protein in the brain tissues of HCD + Cu2+group was also significantly higher than that of the HCD group (P ＜ 0. 05, P ＜ 0. 01). Congo red and Bielschowsky staining showed that the number of senile plaques and neurofibrillary tangles were observed in the brain tissues of the HCD, HCD+Cu2+and senile groups. Conclusions High cholesterol diet or supplemented with trace copper drinking water can induce obvious AD pathological changes in WHBE rabbit models of sporadic AD with obvious oxidative damage, increased Aβ deposition and senile plaque in the brain, and pathological changes of tau. WHBE rabbit can be used in the study of animal models of neurodegenerative diseases.

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.

Effects of Oligosaccharide Esters of Polygala tenuifolia on the Injury of Human Neuroblastoma SH-SY5Y Cells Induced by Aβ25-35 Fragment / 中国药学杂志

OBJECTIVE: To investigate the effects of oligosaccharide esters of Polygala tenuifolia on Aβ25-35 induced injury in SH-SY5Y cells and the relative mechanisms. METHODS: SH-SY5Y cells were cultured with Aβ25-35(25 μmol•L-1) for 24 h in the presence and absence of oligosaccharide esters component of Polygala tenuifolia. The cell viability was measured by MTT method; cell apoptosis was detected by flow cytometry; the LDH release, the SOD activity and MDA level were measured by biochemistry method; the Bcl-2 and Bax expression were determined by Western blotting. RESULTS: Oligosaccharide esters of Polygala tenuifolia could enhance the cell viability, decrease the apoptotic rate, the release of LDH and MDA level, and increase SOD activity. It also enhanced the expression of anti-apoptotic protein Bcl-2 and decreased the expression of apoptotic protein Bax. CONCLUSION: Oligosaccharide esters of Polygala tenuifolia have neuroprotective effects against the Aβ25-35 induced injury in SH-SY5Y cells, which is related to its anti-oxidation and anti-apoptosis.

Inhibitory effect of curcumin on Aβ1-42-induced cell damage and mitochondrial pathway apoptosis / 中国药理学与毒理学杂志

OBJECTIVE To investigate the protective effect of curcumin on Aβ1-42 damaged cells. METHODS SH-SY5Y cells were cultured with Aβ1-4210μmol · L-1 in the absence or presence of curcumin 1, 5 or 10 μmol · L-1. Cell viability was assayed by MTT. Cell membrane damage was detected by the concentration of lactate dehydrogenase (LDH) in culture medium. Cell apoptosis was measured by flow cytometry with Annexin Ⅴ-FITC/PI staining. Mitochondrial membrane potential was characterized by fluorescence of JC-1 dye. Enzymatic activity of caspases-9 and-3 was measured by colorimetric assay. Protein expression of caspase-3 was detected by Western blotting. RESULTS Compared with vehicle control, the cell viability, concentration of LDH and both early and late apoptosis in Aβ1-4210 μmol · L-1 damaged group were decreased(P<0.01). However, the cell viability, release of LDH and both early and late apoptosis in curcumin group were promoted compared with that in Aβ1-4210μmol·L-1 damaged group. Curcumin inhibited Aβ1-42-induced depolarization of mitochondrial membrane potential(P<0.01), and attenuated Aβ1-42-induced activation of both caspases9 and caspases3 in a concentration-dependent manner, respectively(r=0.990, P<0.01; r=0.996, P<0.01). There were no significant differences in the above detected indexes between curcumin 10 μmol · L-1 group and vehicle control group. CONCLUSION Curcumin inhibits Aβ1-42-induced cell damage and apoptosis by promoting mitochondrial membrane potential and depressing the activation of caspases.

Effect of Salidroside on Learning and Memory Abilities and Expression of p75NTR Signal Transducers and Aβ in Hippocampus of AD Rat / 医药导报

Objective To study the effect of salidroside (Sal) on learning and memory abilities and expression of p75NTR signal transducers and Aβ in AD rat hippocampus.Methods Totally,ninety-six male SD rats were randomly divided into sham-operation group,model control group,Sal low,medium and high dose group,Hup-A group (16 rats in each group).Except for sham-operation group,AD model in the other group was established by slowly injecting 1μL(10 μg)Aβ1-40 in tobilateral hippocampal CA1 area.Sham-operation group was given the same volume of 0.9％ sodium chloride solution.Sal low,medium and high dose group took orally as early as 24 h postoperatively with salidroside 25,50,100 mg· kg-1 for 21days,while Hup-A group took 50 mg kg-1 of Hup-A orally.The same volume of 0.9％ sodium chloride solution was administrated in shanmoperation group and model control group.After administration,the learning and memory function of rats were tested by Morris water maze.The contents of Aβ in serum and hippacampus were determined by ELISA,and protein expression of p75NTR and p-JNK in the hippocampus of the rats were measured by ELISA.Results Compared with model control group,the latent time in water maze training of Sal low,medium and high dose groups were significantly shortened (P ＜ 0.05 or P ＜ 0.01),the number of times of crossing platform of Sal low,medium and high dose group was significantly increased.The contents of Aβ in the hippocampus and the protein expression levels of p75NTR and p-JNK in the hippocampus of Sal low,medium and high dose group were decreased significantly (P ＜ 0.05,P ＜ 0.01).Conclusion Salidroside has protective effects on learning and memory consolidation of dysmnesia rats caused by Aβ.Its mechanism might be related to inhibition of p75NTR regulation pathways for Aβ,reducing the neurotoxic effect of Aβ,so as to reduce cell apoptosis of hippocampus neuron.

Protective effect of chlorogenic acid on beta-amyloid protein 25-35-induced PC12 cell apoptosis / 实用医学杂志

Objective To study the protective effect of chlorogenic acid(CGA)on the apoptosis of PC12 cells induced byβ-amyloid protein23-35(Aβ25-35)and its mechanism. Methods The cells model of death was estab-lished by Aβ25-35 (20 μmol/L)-induced PC12 cells. The cells were interfered with 5 different concentrations of CGA. CCK-8 assay was used to detect cells viability to determine the 3 concentrations of CGA in future experi-ments. The cells were divided randomly into control group ,model group and interference groups with 3 different concentrations of CGA. Cells apoptosis rates were detected by flow cytometry;colorimetry method was used to detect MDA,SOD and GSH-Px. The mitochondrial membrane potential(MMP)was detected by fluorescent staining and the expression of caspase-3 by western blot. Results Compared with model group,the cells viability of CGA groups were increased but the apoptosis rates were reduced;the activity of SOD and GSH-Px were increased but the level of MDA,MMP and caspase-3 were decreased(P<0.05). Conclusions CGA has a protective effect on Aβ25-35-induced PC12 cells apoptosis and it may be related to the improvement of cellular antioxidation capacity and mitochondrial damage.