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Aim To investigate the effect of ellagic acid (EA) on cognitive function in APP/PS 1 double- transgenic mice, and to explore the regulatory mechanism of ellagic acid on the level of oxidative stress in the hippocampus of double-transgenic mice based on the phosphatidylinositol 3-kinase/protein kinase B/glycogen synthase kinase-3 (PI3K/AKT/GSK-3 β) signaling pathway. Methods Thirty-two SPF-grade 6-month-old APP/PS 1 double transgenic mice were randomly divided into four groups, namely, APP/PS 1 group, APP/PS1 + EA group, APP/PS1 + LY294002 group, APP/PS 1 + EA + LY294002 group, with eight mice in each group, and eight SPF-grade C57BL/6J wild type mice ( Wild type) were selected as the blank control group. The APP/PS 1 + EA group was given 50 mg · kg
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Objective::To study whether long-term administration of Gastrodiae Rhizoma powder can improve the learning and memory ability of APPswe/PSldE9 double transgenic (APP/PS1) Alzheimer' s disease(AD) model mice and delay the progress of AD whether these effects are related to the regulation of antioxidant stress pathway in Kelch-like epoxylopropylamine-related protein 1(Keap1)-nuclear factor E2 related factor 2 (Nrf2)/heme oxygenase(HO)-1, and further explore the neuroprotective mechanism of Gastrodiae Rhizoma powder and its role in the prevention and treatment of AD. Method::APP/PS1 double transgenic mice model, the mice consisted of five groups: normal, normal administration group, model group, Gastrodiae Rhizoma powder prevention group, Gastrodiae Rhizoma powder treatment group.The mice in the normal administration group and the Gastrodiae Rhizoma powder prevention group were given the same dose of Gastrodiae Rhizoma powder (1.5 g·kg-1) daily at the age of 8 weeks.The normal group and model group were given the same amount of normal saline at the same time, until 24 weeks old, Morris water maze was used to test the learning and memory ability of mice, and the treatment group was treated with Gastrodiae Rhizoma powder at 22 weeks old.The mice were given the same dose of Gastrodiae Rhizoma powder (1.5 g·kg-1) every day for 2 weeks.The number of crossing platform, escape latency and platform residence time of mice were detected by Morris water maze from 24 weeks old to 24 weeks old.RNA, Real-time PCR was extracted from mouse hippocampus to detect the mRNA level of Nrf2, HO-1, Keap1, and Western blot was used to detect the expression of Nrf2, HO-1, Keap1 protein in mouse hippocampus. Result::Compared with normal group, the water maze test showed that the learning and memory ability of model group was lower than that of the model group (P<0.01), and the learning and memory ability of Gastrodiae Rhizoma powder prevention group and Gastrodiae Rhizoma powder treatment group was significantly higher than that of model group (P<0.01). Compared with normal group, the levels of Nrf2, HO-1 and protein in the hippocampus in model group decreased in varying degrees (P<0.05). Compared with model group, Gastrodiae Rhizoma powder prevented Nrf2, in the hippocampus of mice in model group.The level of HO-1 in mRNA and protein increased in different degrees (P<0.05, P<0.01). Levels of Nrf2, HO-1 mRNA in Gastrodiae Rhizoma powder treatment group was significantly higher than that in Gastrodiae Rhizoma powder group (P<0.05). There was no significant difference in the expression of Nrf2, HO-1 protein.There was no significant difference in mRNA and protein levels of Keap1 among different groups. Conclusion::Morris water maze test and other results showed that Gastrodiae Rhizoma powder could improve the learning and memory ability of APP/PS1 mice, and it may enhance the expression of downstream antioxidant genes by regulating Keap1-Nrf2/HO-1 pathway.And then improve the learning and memory ability of APP/PS1 mice.
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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.
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AIM:To explore the therapeutic effect of a novel Rho kinase inhibitor FSD-C10 onβ-amyloid pro-tein precursor (APP)/presenilin-1 (PS1) double transgenic mice.METHODS: The transgenic mice overexpressing hu-man APP with the Swedish mutation (695) and human PS1 with ΔE9 mutation at the age of 8 months were used in this study.The mice were randomly divided into model group and FSD-C10 intervention group, and wild-type mice at the same age served as normal controls .The mice in FSD-C10 intervention group were treated with FSD-C10 (25 mg· kg-1 · d-1 ) for 2 months by intraperitoneal injection .The mice in model group and the wild-type mice were injected with saline in the similar manner.Morris water maze (MWM) test was applied to examine the capacity of learning and memory .The Aβ1-42 deposition, Tau protein phosphorylation , and the expression of β-site APP-cleaving enzyme ( BACE) as well as inflammato-ry molecules, such as TLR-4 and NF-Κb, and M1/M2 microglial markers, such as Inos and Arg-1, were determined by the methods of immunohistochemistry and Western blot .RESULTS: Compared with model group , FSD-C10 significantly improved the learning and memory abilities of APP/PS1 double transgenic mice , accompanied by reduced Aβ1-42 deposi-tion, Tau protein phosphorylation and BACE expression in the hippocampus .The intervention of FSD-C10 decreased the protein levels of TLR-4 and p-NF-Κb, reduced the expression of Inos and increased the expression of Arg-1 in the brain tissues.CONCLUSION:The novel Rho kinase inhibitor FSD-C10 improves the capacity of spatial learning and memory in APP/PS1 double transgenic mice , which may be related to the inhibition of TLRs/NF-Κb signaling pathway , the reduction of the secretion of inflammatory molecules and the polarization of anti-inflammatory M2 microglia, thus improving the in-flammatory microenvironment of the brain in APP/PS1 double transgenic mice .
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AIM:To explore the therapeutic effect of a novel Rho kinase inhibitor FSD-C10 onβ-amyloid pro-tein precursor (APP)/presenilin-1 (PS1) double transgenic mice.METHODS: The transgenic mice overexpressing hu-man APP with the Swedish mutation (695) and human PS1 with ΔE9 mutation at the age of 8 months were used in this study.The mice were randomly divided into model group and FSD-C10 intervention group, and wild-type mice at the same age served as normal controls .The mice in FSD-C10 intervention group were treated with FSD-C10 (25 mg· kg-1 · d-1 ) for 2 months by intraperitoneal injection .The mice in model group and the wild-type mice were injected with saline in the similar manner.Morris water maze (MWM) test was applied to examine the capacity of learning and memory .The Aβ1-42 deposition, Tau protein phosphorylation , and the expression of β-site APP-cleaving enzyme ( BACE) as well as inflammato-ry molecules, such as TLR-4 and NF-Κb, and M1/M2 microglial markers, such as Inos and Arg-1, were determined by the methods of immunohistochemistry and Western blot .RESULTS: Compared with model group , FSD-C10 significantly improved the learning and memory abilities of APP/PS1 double transgenic mice , accompanied by reduced Aβ1-42 deposi-tion, Tau protein phosphorylation and BACE expression in the hippocampus .The intervention of FSD-C10 decreased the protein levels of TLR-4 and p-NF-Κb, reduced the expression of Inos and increased the expression of Arg-1 in the brain tissues.CONCLUSION:The novel Rho kinase inhibitor FSD-C10 improves the capacity of spatial learning and memory in APP/PS1 double transgenic mice , which may be related to the inhibition of TLRs/NF-Κb signaling pathway , the reduction of the secretion of inflammatory molecules and the polarization of anti-inflammatory M2 microglia, thus improving the in-flammatory microenvironment of the brain in APP/PS1 double transgenic mice .
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This study was aimed to investigate the effects of Bu-Yang Huan-Wu (BYHW) decoction to the learning and memory ability of APP/PS1 double transgenic mice through two behavior tests,in order to observe the Alzheimer's disease (AD) treatment effect of BYHW decoction.A total of 60 APP/PS1 double transgenic mice were randomly divided into five groups,which were the model group,the hydrochloride group,the high-,middle-,and low-dose BYHW decoction group,with ten rats in each group.The C57BL/6J mice were used as the control group.After 30 days of drug administration,all mice were subjected to behavior tests,including new object recognition experiment and step-through task.Western blot was used to detect changes of inflammatory factors,including IL-6 and TNF-α,in hippocampus of mice.The results showed that compared with the model group,the high-and middle-dose BYHW decoction can significantly decrease inflammatory factors of IL-6 and TNF-α expression in hippocampus of APP/PS1 mice.It can also obviously improve the learning and memory ability of APP/PS1 mice.It was concluded that BYHW decoction can significantly decrease the inflammatory factor expression in APP/PS 1 double transgenic AD model mice.It can obviously improve its learning and memory ability,which can be used in the treatment of AD.
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Aim Toobservetheeffectofconcisepre-scriptions of Chinese medicine Huannao Yicong Decoc-tion(HYD)on regulatory pathway of secretase in APP/PS1 double transgenic cell line(HEK293),and to in-vestgateitsmechanism.Methods Theproliferationof AD cell model and the toxicity of each investigational drugs were ebserved by CCK-8;the changes in micro-scopic structure of each group were observed by(Trans-mission electron microscope,TEM);the activities of gamma-secretes was observed by Dual Luciferase Re-porter Gene Assay Kit ,and then the expression of pre-senilin 1(PS1),carboxyl terminus of Hsc70-interacting protein(CHIP),GTP binding protein (CDC42 ),ante-rior pharynx defective-1α(APH-1α),Hypoxia induc-ible factor-1α(HIF-1α) were detected by Western blot.Results 15%HYDserumincreasedthecellac-tivity compared to blank serum (P 0. 05 );compared to control group,HYD directly group inhibited the HIF-1αprotein ex-pression after 48h medication(P<0. 05);compared to 0h midicaiton,DAPT group inhibited the HIF-1αpro-tein expression at the point of 24 h (P<0. 05 ).Con-clusions HYDcantreatADthroughprotectingthe mitochondrial function,reducing the formation of lipo-fuscin,inhibiting the activity of γsecretase by down-regulating the activity of HIF-1α,decreasing the stabil-ity and activity of PS1 by promoting the expression of CDC42.This shows that HYD has good research and development prospect as an effective drug for preven-tion and treatment of AD.
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Objective To investigate the effects of Dihuangyinzi(DHYZ) on behaviors and RAGE/p38 pathway in APP/PS1 mice.MethodTwenty APP/PS1 dementia mice were randomly divided into model group(n=10) and Chinese medicine group(n=10).The blank group was C57 BL/6 J normal mouse(n=10).The mice in Chinese medicine group were intragastric administration with DHYZ (9.75 g·kg-1·d-1).The mice in model group and blank group were treated with distilled water.After 30 days,the abilities of learning and memory of mice were detected by Morris water maze.The expression of amyloid-beta1-42(Aβ1-42) in the hippocampus and cortex was detected by immunohistochemistry.Reactive oxygen species of brain tissue were detected by DCFH-DA Methods in the brain of APP/PS1 mice.Gene expression level of receptor for advanced glycation end products(RAGE) was measured by real-time polymerase chain reaction (RT-PCR) in the cortex and hippocampus of APP/PS1 mice.The expression of phospho-mitogen-activated protein kinases (p38) was analyzed with Western blot and immunofluorescence analysis in the cortex and hippocampus of APP/PS1 mice.Results Behavioral Results showed that DHYZ significantly increased the distance((23.088±7.083)cm) and residence time((1.961±1.230)s)of effective area in Morris water maze on the fifth day(P<0.05,P<0.01)and remarkably increased the number of effective area crossings((1.607±0.405) times) and plats((0.893±0.283) times) in Morris water maze on the fifth day(P<0.01,P<0.05).DHYZ also significantly reduced the intracelluar ROS level(122.611±7.630) in the brain(P<0.01),and DHYZ could depress the expression of RAGE(1.467±0.081,7.983±0.136) and phosphorylation of p38 (0.376±0.026,0.538±0.016)in the cortex and hippocampus of APP/PS1 mice(P<0.01,P<0.05).Conclusions The Results demonstrate that DHYZ can partly improve memory impairment of APP/PS1 mice by the inhibition of RAGE/p38 pathway.
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To investigate the effect of the hyperforin (HF) on learning and memory function and Aβ₁₋₄₂, βAPP and BACE1 protein expressions in hippocampus of five-month-old APP/PS1 double transgenic mice, and discuss the underlying mechanism of HF. The five-month-old APP/PS1 double transgenic mice were randomly divided into the model group, rosiglitazone group (12 mg•kg⁻¹•d⁻¹) and HF high dose, middle dose and low dose groups (600, 300 and 150 mg•kg⁻¹•d⁻¹) in each group; in addition, 15C57BL/6J mice with the same months and background were selected as normal group. Drugs were diluted in the same volume before using, and then administrated by ig for 7 months, 1 time a day; the mice in normal group and model group received the same volume of distilled water. The learning and memory ability was tested by Morris water maze; Aβ₁₋₄₂, βAPP and BACE1proteinexpressionlevelswere tested by immunohistochemistry and Western blot. The Morris water maze results showed that as compared with the normal group, the learning and memory ability was significantly impaired in mice of model group (P<0.01); as compared with the model group, the learning and memory ability was improved in mice of rosiglitazone group and HF high, middle and low dose groups(P<0.01 or P<0.05). Immunohistochemistry and western blot results showed thatas compared with the normal group, the Aβ₁₋₄₂, βAPP and BACE1 protein expression levels in hippocampus were significantly increased in mice of model group (P<0.01);as compared with the model group, Aβ₁₋₄₂, βAPP and BACE1 protein expression levels in hippocampus were decreased in mice of rosiglitazone group and HF high, middle and low dose groups (P<0.01 or P<0.05). HF may improve the learning and memory ability of AD model mice via inhibition of βAPP and BACE1 protein expressions, thus reduced the generation of Aβ₁₋₄₂ proteins and amyloid plaque deposits in the brain.
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AIM:To investigate the protective effects of astrocyte protein phosphatase 2A (PP2A) up-regula-tion on APP/PS1 double transgenic mice.METHODS:An eGFP-wtPP2A lentivirus with glial fiber acidic protein promoter was constructed to specifically increase PP2A expression in the astrocytes.The mice were divided into wild -type mice +vector virus group (Con), APP/PS1 transgenic mice +vector virus group (APP/PS1) and APP/PS1 transgenic mice +eGFP-wtPP2A lentivirus group (PP2A) by lateral ventricular injection of the lentivirus.Four weeks after injection of the vi-rus, the immunofluorescence of brain slices were used to detect the level of β-amyloid protein ( Aβ) .Golgi staining was used to detect the changes of dendritic spine density and morphology.Electron microscopy was applied to detect the thickness of postsynaptic density (PSD).The Morris water maze test was applied to examine the learning and memory abilities of the mice.RESULTS: Up-regulation of PP2A in the astrocytes attenuated Aβlevel increasing in APP/PS1 group.Up-regulation of PP2A in the astrocytes significantly attenuated both decreases in the dendritic spine density and the percentage of mushroom-like dendritic spines in the hippocampal CA3 region of APP/PS1 mice.Up-regulation of PP2A in the astrocytes significantly attenuated the reduced thickness of PSD in APP/PS1 group.Up-regulation of PP2A in the astro-cytes attenuated the escape latency extending in APP/PS1 group .CONCLUSION: Up-regulation of PP2A in the astro-cytes reduces AD-like pathological changes, and attenuates synaptic impairment, synaptic plasticity deficits and cognitive impairment in the APP/PS1 double transgenic mice.
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Objective To investigate the effects of Abnormal Phlegmatic Temperament Granules on spatial learning and memory, histopathology morphological change in hippocampus CA1 zone; To discuss its mechanism of action.Methods Three-month-old APP/PS1 transgenic mice were randomly divided into 5 groups: model control group, positive control (donepezil 0.92 mg/kg) group, Abnormal Phlegmatic Temperament Granules high-, medium-, and low-dose groups (3, 2, 1.5 g/kg), 18 mice in each group. Another 18 three-month-old C57BL/ 6J mice were chosen as normal control group. All administration groups received relevant medicine for successive 6 months. Then the changes in learning and memory ability of mice were detected by Morris water maze test; pathomorphism in hippocampus CA1 zone was detected by HE staining method; changes of myelin sheath, microtubule, and microfilament in myelinated nerve of hippocampus CA1 zone were detected by electron microscope. Results Morris water maze test results showed that escape incubation period of APP/PS1 transgenic mice was significantly longer than the normal control group (P<0.01), and the original platform time was significantly shorter than normal control group (P<0.01); compared with model control group, Abnormal Phlegmatic Temperament Granules treatment groups escape latency time was significantly reduced (P<0.05, P<0.01). Space experiments and escape incubation period of Abnormal Phlegmatic Temperament Granules high-, medium-, low-dose groups were significantly shortened (P<0.05, P<0.01), and spatial searching test showed that the times of mice in Abnormal Phlegmatic Temperament Granules high-, medium-, low-dose groups passing through effective area increased (P<0.01). The integrity of HE staining pyramidal cell layer in the hippocampus CA1 zones of Abnormal Phlegmatic Temperament Granules high-, medium-, and low-dose groups was relatively good; cells arranged orderly; distribution was normal. Electron microscopic observation showed that compared with model control group, the hippocampus neurons nuclear had irregular shape; nuclear membrane was clear and complete; chromatin was clear; nucleolus was obvious; cell matrix was uniform; organelles were abundant; mitochondrial cristae was obvious; endoplasmic reticulum and free ribosomes were obvious. Conclusion Abnormal Phlegmatic Temperament Granules can improve spatial learning and memory in APP/PS1 mice, alleviate neuronal ultrastructure damage and ultimately improve cognitive function.
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Alzheimer's disease (AD) is the most common neurodegenerative disease without known ways to cure. A key neuropathologic manifestation of the disease is extracellular deposition of beta-amyloid peptide (Abeta). Specific mechanisms underlying the development of the disease have not yet been fully understood. In this study, we investigated effects of 4-O-methylhonokiol on memory dysfunction in APP/PS1 double transgenic mice. 4-O-methylhonokiol (1 mg/kg for 3 month) significantly reduced deficit in learning and memory of the transgenic mice, as determined by the Morris water maze test and step-through passive avoidance test. Our biochemical analysis suggested that 4-O-methylhonokiol ameliorated Abeta accumulation in the cortex and hippocampus via reduction in beta-site APP-cleaving enzyme 1 expression. In addition, 4-O-methylhonokiol attenuated lipid peroxidation and elevated glutathione peroxidase activity in the double transgenic mice brains. Thus, suppressive effects of 4-O-methylhonokiol on Abeta generation and oxidative stress in the brains of transgenic mice may be responsible for the enhancement in cognitive function. These results suggest that the natural compound has potential to intervene memory deficit and progressive neurodegeneration in AD patients.