アルツハイマー病、他の認知症、老化 Alzheimer's Disease, Other Dementia, Aging
P1-1-192 HDAC阻害剤はアミロイドβによるシナプス障害を防ぐ Histone deacetylase (HDAC) inhibitor attenuates amyloid beta-induced synaptic dysfunction ○石塚佑太1, 清水英雄1, 高木瑛子1, 白尾智明1 ○Yuta Ishizuka1, Hideo Shimizu1, Eiko Takagi1, Tomoaki Shirao1 群馬大院・医・神経薬理1 Dept. Neurobiol & Behav, Gunma Univ Grad Sch Med1 Impairment of dendritic spines is common to several forms of dementia, such as Alzheimer's disease. Amyloid β (Aβ ) is thought to be involved in the pathogenesis through dendritic spine impairment. Aβ toxicity resides not only in fibrils, but also in soluble oligomers. Actually soluble oligomers are pathologically more potent than the fibrillar amyloid deposits. Drebrin is a good marker of mature dendritic spines, but the Aβ -oligomer has been reported to decrease drebrin accumulation in the dendritic spines. Recent studies reported that epigenetic modification is involved in the neurological diseases. In this study, we hypothesized that histone modifications have important roles in the synaptic response to the stress, and examined the protective activity of suberoylanilide hydroxamic acid (SAHA), a histone deacetylase (HDAC) inhibitor, against Aβ oligomers-induced synaptic changes. We prepared primary hippocampal culture according to Banker's method, added SAHA and Aβ -oligomer to the culture at 21 days in vitro. Aβ -oligomer treatment decreased the number of drebrin clusters along dendrites, but not synapsin-1 clusters, a presynaptic marker. SAHA treatment inhibited the Aβ -oligomer induced decrease of drebrin clusters, while SAHA treatment did not affect the drebrin and synapsin-1 cluster density in the control culture. These results suggest that HDAC is specifically involved in the Aβ -oligomer induced decrease of drebrin cluster density and SAHA has protective effect on dendritic spine.	P1-1-193 海馬切片培養標本を用いたβ-セクレターゼの解析 β-secretase (BACE1)processing of amyloid precursor protein(APP) in Organotypic hippocampal slice cultures ○上窪裕二1, 櫻井隆1 ○Yuji Kamikubo1, Takashi Sakurai1 順天堂大・医・薬理1 Dept Pharmacol, Juntendo Univ Sch Med, Tokyo, Japan1 Amyloid beta (Aβ) is a peptide of 36-43 amino acids that formed after sequential cleavage of the amyloid precursor protein (APP). Aβ is the main component of deposits found in the brains of patients with Alzheimer's disease. APP can be processed by α-, β- and γ-secretases. Aβ protein is generated by successive action of the β- and γ-secretases. The γ secretase, which produces the C-terminal end of the Aβ peptide, cleaves within the transmembrane region of APP and can generate Aβ40 and Aβ42. Processing of APP by BACE1 plays a crucial role in the pathogenesis of Alzheimer disease (AD). Furthermore, BACE1 is important in the formation of myelin sheaths. BACE1 activity and generation of Aβ is coupled to neuronal activity, but the molecular basis is unknown. Here, we show the methods for analysis of BACE1 and formation and secretion of endogenous Aβ and sAPPβ in organotypic hippocampal slice cultures. This preparation contains the lamellar neuronal network of hippocampus in vivo. Furthermore, in previous reports using organotypic hippocampal slice cultures, we showed induction of short and long term synaptic plasticity and synapse formation and elimination. Organotypic hippocampal slice cultures are good model for pharmacological manipulation and chronic assay of Aβ secretion.
P1-1-194 運動は継続しなければ高脂肪食によるアルツハイマー病症状の悪化を改善できない The continuation of exercise is necessary to inhibit high fat diet-induced β-amyloid deposition and memory deficit in amyloid precursor protein transgenic mice ○前迫真人1, 岩田彩奈1, 久保田正和1, 植村健吾2, 木下彩栄1 ○Masato Maesako1, Ayana Iwata1, Masakazu Kubota1, Kengo Uemura2, Ayae Kinoshita1 京都大院・医・人間健康科学1, 京都大院・医・臨床神経学2 Dept Human Health Sciences, Kyoto Univ, Kyoto1, Dept Neurology, Kyoto Univ, Kyoto2 [Background] High fat diet (HFD) is prevalent in modern society and HFD-induced metabolic condition is becoming a worldwide issue. Importantly, accumulating evidence suggests that HFD increases the risk of developing sporadic Alzheimer disease (AD). We have previously gave HFD to amyloid precursor protein (APP) transgenic mice (APP-HFD mice) and APP-HFD mice have shown increasing β-amyloid (Aβ) deposition and worsening of cognitive function compared to control APP mice on normal diet. Moreover, we have reported that environmental enrichment-based voluntary exercise is more effective than diet control in the improvement of HFD-induced memory impairment and Aβ deposition. [Purpose] To make clear whether HFD abolished the positive effect of exercise on the inhibition of AD development after finishing exercise. [Methods] We exposed wild type (WT)-HFD and APP-HFD mice to the exercise condition at different time periods. In the previous experiment, we gave HFD to the mice for 20 weeks and the mice spent in the exercise condition during 10-20 weeks. In the present study, the mice spent in the exercise condition during 0-10 weeks or 5-15 weeks in the presence of HFD. [Results] Surprisingly, we found that the effect of exercise during 0-10 weeks or 5-15 weeks on memory function was not abolished in WT mice even if they kept having HFD. However, we showed that HFD clearly disrupted the effect of exercise during 0-10 weeks or 5-15 weeks on memory function in APP transgenic mice. Importantly, we observed that the levels of Aβ oligomer as well as deposited Aβ were significantly elevated in the APP-HFD mice spent in the exercise condition during 0-10 weeks. This result might be because HFD rapidly promoted the production of Aβ. [Conclusion] These results provide solid evidence that the continuation of exercise is necessary to rescue HFD-induced aggravation of cognitive decline in the pathological setting of AD.	P1-1-195 SOD1欠損マウスにおける行動変化 Neurobiological and behavioral changes in SOD1 knockout mice ○吉原大作1, 藤原範子1, 磯博行2, 北中順惠3, 北中純一3, 江口裕伸1, 崎山晴彦1, 竹村基彦3, 鈴木敬一郎1 ○Daisaku Yoshihara1, Noriko Fujiwara1, Hiroyuki Iso2, Nobue Kitanaka3, Junichi Kitanaka3, Hironobu Eguchi1, Haruhiko Sakiyama1, Motohiko Takemura3, Keiichiro Suzuki1 兵庫医科大学1, 兵庫医療大学2, 兵庫医科大学3 Departments of Biochemistry, Hyogo College of Medicine, Nishinomiya, Japan1, General Education Center, Hyogo University of Health Sciences, Kobe, Japan2, Departments of Pharmacology, Hyogo College of Medicine, Nishinomiya, Japan3 Oxidative stress caused by accumulated reactive oxygen species (ROS) are thought to play a role in many neurodegenerative processes, including aging and pathological conditions, such as Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis (ALS). Neurotransmitter disorder associated with those neurodegenerative diseases may induce learning and memory deficits, depression and impairment in adaptive behavior. However, little is known whether oxidative stress induces neurotransmitter disorder, or not. Cytosolic superoxide dismutase (Cu/Zn-SOD, SOD1) plays a protective role against oxidative stress. Decreased SOD1 activity causes oxidative stress and may increase cognitive impairment. We therefore assessed the motor, cognitive, memory functions of SOD1 KO mice by the open-field, shuttle box learning tests and sociability tests. After these behavioral tests, tissue content of monoamines and the metabolites was determined. SOD1 KO mice exhibited some abnormal behaviors in shuttle box learning tests and alterations in brain monoamine metabolism compared with wild-type mice. Our results indicate that oxidative stress alters monoamine metabolisms in SOD1 KO mice, which may contributes to their abnormal behaviors.
P1-1-196 Low-density lipoprotein receptor-related protein 1(LRP1)によるBACE1の抑制的制御 Suppressive regulation of BACE1 by low-density lipoprotein receptor-related protein 1 (LRP1) ○荒木亘1, 嶺岸正治1, 本木和美1, マデパリラクシュマナ2, 保坂愛1,3, 岡田尚巳4, 玉岡晃3 ○Wataru Araki1, Seiji Minegishi1, Kazumi Motoki1, Lakshmana Madepalli2, Ai Hosaka1,3, Takashi Okada4, Akira Tamaoka3 国立精神・神経医療研究センター神経研・疾病6部1, 筑波大学　神経内科3, 国立精神・神経医療研究センター神経研・遺伝子疾患治療部4 Dept Demyelinating Dis & Aging, National Inst of Neurosci, NCNP, Tokyo, Japan1, Torrey Pines Institute for Molecular Studies, Florida, USA2, Dept of Neurology, Univ of Tsukuba, Ibaraki, Japan3, Dept of Mol Therapy, National Inst of Neurosci, NCNP, Tokyo, Japan4 β-Secretase BACE1 is a membrane-associated aspartyl protease that is essential for the production of amyloid β-protein (Aβ), the pathogenic factor in Alzheimer's disease. Low-density lipoprotein receptor-related protein 1 (LRP1) is a transmembrane receptor that is involved in endocytosis of amyloid precursor protein (APP). LRP1 also appears to be a substrate of BACE1. In this study, we investigated the molecular relationship between BACE1 and LRP1. The protein expression level of BACE1 in LRP1 knockout cells was significantly higher than that in wild-type cells. When BACE1 was co-expressed with or without LRP-L4, a functional minireceptor of LRP1, in HEK293 cells, the protein level of BACE1 in cells co-expressing BACE1 and LRP-L4 was remarkably decreased compared with that in cells expressing BACE1 alone. This effect was dependent on the expression level of LRP-L4. In contrast, the protein level of APP or BACE2 was not affected by LRP-L4 when co-expressed in HEK293 cells. When BACE1 and LRP1 were co-expressed in primary cerebral cortical neurons via recombinant adenoviruses, the expression of BACE1 was similarly suppressed by LRP1. Furthermore, LRP-L4 inhibited Aβ secretion from neurons co-expressing Swedish mutant APP and BACE1. Co-immunoprecipitation experiments revealed interaction of BACE1 and LRP-L4. Additionally, we obtained data indicating that LRP1 reduced the cell surface expression of BACE1. These results suggest that LRP1 can negatively modulate the protein expression, trafficking and function of BACE1 possibly through protein interaction.	P1-1-198 老化促進マウス（SAM）海馬CA1における時間的・空間的シグナル伝達異常―多電極アレイ計測 Synaptic dysfunction and defective activity propagation in hippocampus CA1 of young senescence-accelerated mice ○北村宏幸1, 舘野高1 ○Hiroyuki Kitamura1, Takashi Tateno1 北海道大院・情報・生態計測1 Dept IT, Hokkaido Univ, Sapporo1 The senescence-accelerated mouse (SAM) has been used in studies of aging, and there are now 11 prone lines (SAM-P). Each SAMP-P line has strain-specific age-related pathological phenotypes, such as loss of nerve cells, amyloidosis, hearing loss, and memory disorder. In contrast to SAM-R1 (healthy control), the aged SAM-P8 and -P10 have particularly characteristic features including, i.e., brain atrophy, loss of neural receptor channels, or memory and learning disorder. However, in younger SAM, little has been known about premonitory symptoms, which could afterward lead to age-related neural disorder such as Alzheimer's disease. In this study, among young SAM-P8, P10, and R1, we aimed to investigate differences of synaptic function in CA1. Using young SAM and multi-electrode arrays, we recorded local field potentials by stimulating Schaffer collaterals in the CA1 stratum radiata of hippocampal slices. The result showed that EPSPs in SAM-P8 were profoundly weaker than those in SAM-R1. In addition, we found that, in SAM-R1 the relationship between EPSP amplitude and distance from a stimulation site was monotonically decreasing, while the relationship in SAM-P10 was non-monotonic or fluctuating, indicating the tessellated distribution of the evoked EPSPs. To investigate activity-dependent plasticity, we studied long-term potentiation and paired-pulse facilitation. The result showed that, among these young SAM strains, magnitudes of the long-term potentiation were not significantly different, but they highly depended on the distance from stimulation sites. In the paired-pulse facilitation, in contrast, to successive short current pulses, amplitude ratios between first and second evoked EPSPs in SAM-P8 were higher than those in SAM-R1 and -P10, suggesting hyperexcitability in SAM-P8. Thus, the specific phenotypes observed in the SAM-P strains can have a link to pathological and functional symptoms seen in the age-related deterioration of memory and learning abilities.
P1-1-199 アルツハイマー病脳のdystrophic neuritesにおけるC9orf72の発現 Dystrophic neurites express C9orf72 in Alzheimer's disease brains ○佐藤準一1, 天竺桂弘子1, 石田剛2, 齊藤祐子3, 有馬邦正4 ○Jun-ichi Satoh1, Hiroko Tabunoki1, Tsuyoshi Ishida2, Yuko Saito3, Kunimasa Arima4 明治薬科大学バイオインフォマティクス1, 国立国際医療センター国府台病院中央検査部2, 国立精神神経医療研究センター病院臨床検査部3, 国立精神神経医療研究センター病院精神科4 Dept Bioinformatics, Meiji Pharm Univ, Tokyo, Japan1, Dept Pathol Lab Med, Kohnodai Hosp, NCGM, Chiba, Japan2, Dept Lab Med, National Center Hosp, NCNP, Tokyo, Japan3, Dept Psychiat, National Center Hosp, NCNP, Tokyo, Japan4 Objective: We attempted to investigate the expression of chromosome 9 open reading frame 72 (C9orf72) in Alzheimer's disease (AD) brains. Background: C9orf72 is an evolutionarily conserved protein with unknown function, expressed at high levels in the brain. An expanded hexanucleotide GGGGCC repeat located in the first intron of the C9orf72 gene represents the most common genetic cause of familial frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). Previous studies by immunohistochemistry with two different anti-C9orf72 antibodies named sc-138763 and HPA023873 showed that C9orf72 is expressed chiefly in the cytoplasm of neurons, and concentrated in the synaptic terminals in the brains of FTD/ALS with or without C9orf72 repeat expansion as well as those of the controls (DeJesus-Hernandez M et al. Neuron 72:245, 2011; Snowden JS et al. Brain 135:693, 2012). At present, a pathological role of C9orf72 in the process of neurodegeneration remains unknown. Methods: By immunohistochemistry, we studied C9orf72 expression in the frontal cortex and the hippocampus of 6 AD and 13 control cases, including ALS, Parkinson's disease, multiple system atrophy, and non-neurological cases. Results: The HPA023873 antibody showed a cross reactivity to GFAP, and therefore stained intensely reactive astrocytes in AD and non-AD brains. Both sc-138763 and HPA023873 antibodies labeled the neuronal cytoplasm and the neuropil with variable intensities, and intensely stained a cluster of p62-negative, UBQLN1-positive swollen neurites, which were distributed in the CA1 region and the molecular layer in the hippocampus. Most notably, both of these antibodies reacted strongly with dystrophic neurites accumulated on senile plaques in AD brains. Conclusions: These results suggest a more general role of C9orf72 in the process of neurodegeneration in a range of human neurodegenerative diseases (Satoh J et al. Alzheimers Res Ther 4:33, 2012).	P1-1-200 ADAM10切断阻害変異導入N-カドヘリンマウスの解析 Analysis of N-cadherin shedding deficient knock-in mice ○浅田めぐみ1,2, , 諏訪あゆみ1, 久保田正和1, 野田秦葉1, 田代善崇2, 前迫真人1, 山門穂高2, 下濱俊3, 高橋良輔2, 植村健吾2, 木下彩栄1 ○Megumi Asada1,2, Ayumi Suwa1, Masakazu Kubota1, Yasuha Noda1, Yoshitaka Tashiro2, Masato Maesako1, Hodaka Yamakado2, Shun Shimohama3, Ryosuke Takahashi2, Kengo Uemura2, Ayae Kinoshita11 京都大学大学院　医学研究科　人間健康科学1, 京大病院神経内科2, 札幌医大神経内科3 Dept. Human Health Sci.Grad. Sch. Med.Kyoto Univ.1, Dept.Neuro.Kyoto Univ. Grad. Sch. Med2, Dept.Neuro.Sappro Med.Univ.3 Alzheimer's disease (AD) is the most major cause of dementia. In AD, synaptic loss is one of the principal pathological hallmarks, and correlates with the severity of cognitive impairment. To reveal a mechanism of synaptic loss in the pathogenesis of AD, we focused on N-cadherin, an essential adhesion molecule in synaptic contact. Although it is established that N-cadherin undergoes sequential cleavage by ADAM10 and PS1, a significance of the cleavage has not been clarified. Thus, we analyzed the association of N-cadherin cleavage with cognitive function by using of cleavage-defective N-cadherin (GD mutant) knock-in (KI) mice. GD mutant KI mice were viable and retained normal growth and reproduction capacity, but demonstrated weight loss. In histological analysis, GD mutant KI mice displayed no structural changes in cerebral cortex and hippocampus. In biochemical analysis, the levels of GluT1, GluR1, and phosphorylated Akt were increased at the synaptosomes of GD mutant KI mice. Spatial memory of GD mutant KI mice showed significant difference by Morris water maze test at 12 months of age. However, spatial memory of GD mutant KI mice showed no significant difference by Barnes maze test at 4 months of age. Interestingly, GD mutant KI mice demonstrated better spatial memory compared with WT mice.Enhancement of Akt phosphorylation in synaptosomes of GD mutant KI mice may represent increased neuronal survival signal, leading to better cognitive performance.
P1-1-201 インターロイキン4/インターロイキン13の脳内微量注入は抗炎症性M2様ミクログリアを活性化しアルツハイマー病モデルマウスの空間認知障害を改善する Intracerebral microinjection of interleukin-4/interleukin-13 activates anti-inflammatory M2-like microglia and improves cognitive deficits in Alzheimer's model mice ○川原浩一1,2, 末延道太1,2, 吉田陽1, 古賀清弘1, 兵藤敦1, 大塚英起1,2, 國安明彦1,2, 玉巻伸章3, 杉本幸彦2, 中山仁1 ○Kohichi Kawahara1,2, Michita Suenobu1,2, Akira Yoshida1, Kiyohiro Koga1, Atsushi Hyodo1, Hideyuki Ohtsuka1,2, Akihiko Kuniyasu1,2, Nobuaki Tamamaki3, Yukihiko Sugimoto2, Hitoshi Nakayama1 熊本大・院生命・細胞機能分子解析学1, 熊本大・院生命・薬学生化学2, 熊本大・院生命・脳回路構造学3 Dept. Mol. Cell Funct., Faculty of Life Sci., Kumamoto Univ., Kumamoto, Japan1, Dept. Pharmaceutical Biochem., Faculty of Life Sci., Kumamoto Univ., Kumamoto, Japan2, Dept. Morphological Neural Sci., Faculty of Life Sci., Kumamoto Univ., Kumamoto, Japan3 We previously reported that the anti-inflammatory cytokine interleukin (IL)-4 induced selective clearance of oligomeric β-amyloid (Aβ1-42) in rat primary type 2 microglial cells. For the present study, we investigated whether IL-4 and IL-13 could activate microglial cells to induce Aβ clearance in vivo and improve cognitive deficits in APP23 mice, which are amyloid precursor protein transgenic mice. We administered an intracerebral microinjection of a mixture of IL-4 and IL-13 or of saline vehicle into one hemisphere of APP23 mice and their wild-type littermates, 4.5 and 9 months old, after which we evaluated the effects of these treatments on spatial learning and memory by Morris Water Maze test and on accumulated amounts of Aβ. The cytokine injection significantly improved memory deficits of 4.5-month-old APP23 mice, but did not do so in 9-month-old APP23 mice, even though similar Aβ reductions were observed in both age groups of APP23 mice in the ipsilateral neocortex. The cytokine injection improved memory impairment of 9-month-old WT mice in the probe trial. Immunohistochemical analysis of the 4.5-month-old APP23 mice revealed the presence of increased numbers of microglial cells at 2 days after the cytokine injection. In addition to induced CD36 expression in the activated microglia, increased expression of neprilysin, mainly in neurons, suggested that the cytokines improved the cognitive deficits via degradation and clearance of intra- and extraneuronal Aβ peptides, of buffer-extractable nonplaque form. Double immunostaining also revealed that most of the activated microglia had the M2-like phenotype. This unique mechanism of IL-4/IL-13-induced clearance of Aβ may provide an additional strategy to prevent and/or cure Alzheimer's disease at early stage.

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