一般ポスター
アルツハイマー病 |
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| 7月7日（金） 13:50-14:50 ポスター会場①
2P⑦-1
Sphingosine kinase 1阻害によるミクログリアのAβ取り込み低下を介したニューロンの傷害作用
Sphingosine kinase 1 inhibition aggravates neuronal damage in neuron/glia mixed culture via reduced microglial Aβ uptake
南畑 朋輝, 高野 桂, 森山 光章
大阪府立大学大学院 獣医学専攻 統合生理学教室
Tomoki Minamihata, Katsura Takano, Mitsuaki Moriyama
Laboratory of Integrative Physiology in Veterinary Sciences, Osaka Prefecture University, Osaka, Japan
Glial cells contribute to both the pathogenesis and the exacerbation of Alzheimer’s disease (AD) through neuroinflammation and Aβ clearance. Recent studies have reported that the reduction in sphingosine-1-phosphate (S1P), due to less expression of sphingosine kinase (SK) 1, causes AD pathology. Although the mechanisms that S1P reduction induces AD pathology remain unclear, accumulating evidence have suggested that changes in S1P synthesis can modulate neuroinflammation such as glial cell activation and neuronal cell death. We explored the effect of reduced S1P content on glial inflammation and neuronal survival by using mouse microglial cell line, BV-2, primary astrocyte and neuron/glia mixed culture. Decrease in cellular S1P content by SK1 inhibitor, PF-543 increased lipopolysaccharide (LPS)-induced nitric oxide (NO) production and generation of reactive oxygen species (ROS) in astrocytes. Conditioned medium from astrocytes treated with both PF-543 and LPS augmented ROS generation in BV-2 cells. In neuron/glia mixed culture, PF-543 increased LPS-induced NO production. Moreover, treatment of PF-543 exacerbated Aβ-induced neuronal damage evaluated by the number of neurons having no axons and decreased Aβ uptake by microglia. These results suggest that reduced S1P in AD may contribute to neuronal loss through excessive glial inflammation and less Aβ uptake by microglia. | | 7月7日（金） 13:50-14:50 ポスター会場①
2P⑦-2
プレセニリン１欠損はACEのAβ42-to-Aβ40 およびアンギオテンシン変換活性を阻害する
Presenilin 1 deficiency impairs Aβ42-to-Aβ40- and angiotensin-converting activities of ACE
鄒 鶤1, 高 原1, 孫 陽1, イスラム サデクル1, 中村 知寿1, 富田 泰輔2, 道川 誠1
1. 名古屋市立大学 大学院医学研究科 神経生化学分野, 2. 東京大学大学院薬学系研究科 病態生化学
Kun Zou1, Yuan Gao1, Yang Sun1, Sadequl Islam1, Tomohisa Nakamura1, Taisuke Tomita2, Makoto Michikawa1
1. Dept. of Biochem., Grad. Sch. of Med. Sci., Nagoya City Univ., 2. Lab. of Neuropath. and Neurosci., Fac. of Pharm. Sci., Univ. of Tokyo
Alzheimer’s disease (AD) is associated with amyloid β-protein 1-42 (Aβ42) accumulation in the brain. Aβ42 and Aβ40 are the major two species generated from amyloid precursor protein. We found that angiotensin-converting enzyme (ACE) converts neurotoxic Aβ42 to neuroprotective Aβ40 in an ACE domain- and glycosylation-dependent manner. Presenilin 1 (PS1) mutations account for most of cases of familial AD and lead to an increased Aβ42/40 ratio. However, the mechanism by which PSEN1 mutations induce a higher Aβ42/40 ratio is unclear. Here, we found that ACE purified from PS1-deficient fibroblasts exhibited altered glycosylation and significantly reduced Aβ42-to-Aβ40- and angiotensin-converting activities compared with ACE from wild-type fibroblasts. Overexpression of wild-type PS1 in PS1-deficient fibroblasts restored the Aβ42-to-Aβ40- and angiotensin-converting activities of ACE. Interestingly, PS1 mutants completely restored the angiotensin-converting activity in PS1-deficient fibroblasts, but some PS1 mutants did not restore the Aβ42-to-Aβ40- converting activity. Our findings suggest that PSEN1 mutations increase the Aβ42/40 ratio by reducing the Aβ42-to-Aβ40- converting activity of ACE. | | 7月7日（金） 13:50-14:50 ポスター会場①
2P⑦-3
神経活動依存的SRFコアクチベーターMRTFBと最初期遺伝子発現におけるAmyloid betaの抑制効果
Inhibitory effect of amyloid beta on neuronal-activity-dependent nuclear translocation of MRTFB and gene expression
田渕 明子1, 小林 弥由1, 伊原 大輔1, 東田 千尋2
1. 富山大学学術研究部薬学・和漢系 分子神経生物, 2. 富山大学学術研究部薬学・和漢系 和漢研 神経機能
Akiko Tabuchi1, Miyu Kobayashi1, Daisuke Ihara1, Chihiro Tohda2
1. Lab. of Mol. Neurobiol., Fac. of Pharm. Sci., Univ. of Toyama, Toyama, Japan, 2. Sec. of Neuromed. Sci., Ins. of Nat. Med., Univ. of Toyama, 2630 Sugitani, Toyama
Neuronal activity-dependent gene expression is an important process for higher brain function and thus the dysregulation of this process is a causative of neurological disorders such as Alzheimer's disease (AD). We focus on one of the serum response factor (SRF) transcriptional cofactor, myocardin-related transcription factor-B (MRTFB). Our recent observations reveal that MRTFB translocates into a nucleus in a neuronal activity-dependent manner. Here we hypothesized that amyloid beta (Abeta), observed in AD, disrupts the nuclear translocation of MRTF and gene expression in neurons. We found that Abeta oligomers inhibited the nuclear translocation of MRTFB induced by synaptic activation via treatment of cortical neurons with bicuculline and 4-aminopyridine. Furthermore, Abeta oligomers blocked synaptic activation-mediated expression of the representative SRF-target gene, activity-regulated cytoskeleton-associated protein (Arc) and jun B, but not c-fos. We found that kainic acid-induced nuclear translocation of MRTFB was blocked in hippocampal neurons of older (10 months old) 5 x FAD mice, the model of AD with strong accumulation of Abeta oligomerization. These findings suggest that the dysfunction of MRTFB by blockade of the nuclear translocation and its target gene expression might be involved in the progression of AD pathology. | | 7月7日（金） 13:50-14:50 ポスター会場①
2P⑦-4
Apolipoprotein E Christchurch のiPS細胞由来アストロサイトにおける機能解析
Functional analyses of Apolipoprotein E Christchurch variant in iPS cell-derived astrocytes
村上 玲, 渡部 博貴, 岡野 栄之
慶應義塾大学医学部生理学教室
Rei Murakami, Hirotaka Watanabe, Hideyuki Okano
Department of Physiology, Keio University, School of Medicine
Alzheimer’s Disease (AD) is the most common neurodegenerative dementia characterized by progressive and irreversible cognitive decline. The strongest genetic risk factor of AD pathogenesis is the e4 variant in the Apolipoprotein E (APOE) gene. APOE gene has three main variants, e2, e3, e4, and these variants uniquely differ in AD onset risk. Recent reports have identified several APOE rare variants that confer protective effects against AD onset and progression. Christchurch (Ch) variant is suggested to suppress the onset and progression of AD in the pedigree bearing familial causative mutation. However, the underlying functional mechanism remains to be elucidated. We aim to clarify the AD protective mechanism of APOE Ch variant.We converted APOE e3 human induced pluripotent stem cells (hiPSCs) to APOE e3 Ch by CRISPR/CAS9-mediated genome editing. Astrocytes were induced from APOE e3 and APOE e3 Ch hiPSCs. Then we examined the expression of APOE mRNAs and proteins in APOE e3 and APOE e3 Ch astrocytes. We evaluated the function of lipid transport and found the same level of intracellular lipid accumulation between APOE e3 and APOE e3 Ch. As an AD pathological feature, we found that APOE e3 Ch astrocytes prevent the phosphorylation and propagation of tau.The present iPSC-derived astrocytes models are the promising tool for elucidating the functions of apoE in AD pathology. | | 7月7日（金） 13:50-14:50 ポスター会場①
2P⑦-5
アルツハイマー病に特徴的なタウアイソフォーム蓄積を再現する病態モデルの作製
Tau fibrils with Alzheimer's disease-type structure induce accumulation of both 3-repeat and 4-repeat tau in vitro
菅野 舜介1,2, 鈴掛 雅美1, 斎藤 稔2, 野中 隆1, 長谷川 成人1
1. 東京都医学総合研究所 脳・神経科学研究分野, 2. 日本大学 文理学部 生命科学科
Shunsuke Kanno1,2, Masami Masuda-Suzukake1, Minoru Saito2, Takashi Nonaka1, Masato Hasegawa1
1. Dept. of Brain and Neurosciences, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan, 2. Dept. of Biosciences, College of Humanities and Sciences, Nihon University, Tokyo, Japan
Accumulation of tau protein is a pathological hallmark in the brains of patients with Alzheimer's disease (AD). In AD, 3-repeat (3R) and 4-repeat (4R) tau isoforms accumulate simultaneously, but few models of AD-type tau accumulation using synthetic tau proteins have been reported. Recently, Lovestam et al. reported that recombinant tau fragment (Tau297-391) can form fibrils with a structure identical to tau aggregates from AD brains (Lovestam et. al, eLife 2022). In this study, we examined whether synthetic tau fibrils with AD fold structure induce seed-dependent aggregation of 3R and 4R tau. Tau297-391 fibrils were prepared according to the previous report and their seeding ability was evaluated in vitro. Tau297-391 fibrils effectively promoted aggregation of both 3R and 4R isoforms. Next, Tau297-391 fibrils were introduced into SH-SY5Y cells expressing tau and their seeding activity was analyzed. Immunoblot analysis of the sarkosyl-insoluble fraction showed that Tau297-391 fibrils have high seeding ability for 3R and 4R tau in cultured cells, consistent with in vitro analysis. In conclusion, Tau297-391 fibrils induced a seed-dependent aggregation of both 3R and 4R tau isoforms in vitro and in cultured cells and are useful for modeling AD-like tau accumulation. | | 7月7日（金） 13:50-14:50 ポスター会場①
2P⑦-6
血漿中のEV保護タンパク分離と神経バイオマーカー応用の試み
Isolation of EV-protected protein from plasma and its application as a neural biomarker
赤嶺 祥真1, 金山 大祐2, 魚住 亮太1, 後藤 志帆1, 宮本 哲愼1, 森 康治1, 工藤 喬2, 池田 学1
1. 大阪大学大学院 医学系研究科 精神医学講座, 2. 大阪大学 キャンパスライフ健康支援・相談センター
Shoshin Akamine1, Daisuke Kanayama2, Ryota Uozumi1, Shiho Gotoh1, Tesshin Miyamoto1, Kohji Mori1, Takashi Kudo2, Manabu Ikeda1
1. Dept. of Psychiatry, Osaka University Graduate School of Medicine, Osaka, Japan, 2. Health and Counseling Center, Osaka University, Osaka, Japan
Extracellular Vesicles (EVs) are vesicles thought to be released by almost all cell types, and their composition reflects the state of the cell from which they are released. Neurons and glial cells also release EVs in the brain, which are thought to be used for intercellular communication.Since EVs have a lipid bilayer protecting their contents from the outside world, the inner proteins are not affected by proteases in the blood and are thought to be present in the blood in the same state as when they were released. Therefore, the state of the CNS can be estimated more accurately by isolating and evaluating EVs than by using blood as it is.In this study, we isolated EVs from human plasma by phosphatidylserine affinity purification and analyzed their contents. Since the plasma proteins adhering to the surface of EVs as "protein corona" cannot be removed by simply separating EVs, we further degraded the surface proteins using proteinase K (ProK) to selectively evaluate the proteins inside the EVs. As a result, two central nervous system (CNS)-related proteins protected by EVs in plasma were identified. These proteins remained after ProK treatment but disappeared when prior membrane disruption treatment was applied, suggesting that they are protected by EV structure. We also report on our attempt to use these CNS-related proteins as biomarkers in dementia patients. | |
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