一般ポスター
神経変性疾患-2 |
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| 7月8日（土） 12:50-13:50 ポスター会場①
3P⑦-1
患者脳由来タウ凝集体の立体構造に基づいた新規変異型タウの解析
Analyses of novel mutant tau lacking the region associated with the protofibril interaction
佐藤 祐太1,2, 木村 妙子1, 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
Yuta Sato1,2, Taeko Kimura1, 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
Structural analysis of insoluble tau from patient brains using cryo-electron microscopy (cryo-EM) has revealed their three-dimensional structures. In this study, we produced new deletion mutants based on cryo-EM structures of tau aggregates and analyzed their aggregation in vitro. We focused on the interfacial region between protofilaments of tau filaments observed in Alzheimer’s disease, which is thought to be important for tau aggregation. Two types of mutants (ΔPG and ΔKP) were constructed. In the presence of dextran sulfate, both mutants aggregated as well as the wild-type (WT) tau. Electron microscopic analyses revealed that they formed fibrous structures. Next, the seeding effect of mutant aggregates was examined. When WT aggregates were added to the WT monomer, seed-dependent aggregation was observed, suggesting WT aggregates worked as seeds. While the addition of mutant aggregates to WT monomer failed to aggregate in vitro. Each aggregate was introduced into cultured cells expressing WT tau, and immunoblot analyses of transfected cells were performed. The results showed that WT and ΔPG aggregates functioned as seeds for tau accumulation in cultured cells, while ΔKP aggregates had less seeding activity compared to WT aggregates. These results suggested that the deleted region of ΔKP plays an important role in tau seeding activity, rather than in self-aggregation. | | 7月8日（土） 12:50-13:50 ポスター会場①
3P⑦-2
培養細胞と動物における定量的タウ伝播システムの開発
Development of quantitative tau propagation systems in cultured cells and animals
Zhiwei Yao1,2, 矢内 凜2, 松本 弦2,3, 佐原 成彦1,2, 樋口 真人1,2
1. 東北大学大学院 医学系研究科 量子生命・分子イメージング講座, 2. 量子科学技術研究開発機構 脳機能イメージング研究部, 3. 長崎大学大学院医歯薬学総合研究科
Zhiwei Yao1,2, Rin Yanai2, Gen Matsumoto2,3, Naruhiko Sahara1,2, Makoto Higuchi1,2
1. Department of Quantum Biology and Molecular Imaging, Tohoku University School of Medicine, Sendai, Japan, 2. Department of Functional Brain Imaging, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan, 3. Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
Tauopathy belongs to a class of neurodegenerative diseases characterized by depositions of filamentous tau proteins. Mouse models of tau propagation have been generated by injecting tau seeds intracerebrally. However, it is essential to construct protocols for assaying the amount and degree of polymerization of tau seeds to apply such experimental models to robust etiological and therapeutic assessments.We aimed to develop biochemical and morphological characterization of tau seeds.Tau seeds were prepared by the heparin-induced polymerization of recombinant 2N4R human(hu)tau, microtubule-binding domain (K18) with or without P301L mutation. For the disease control brain-derived tau seed, tau fibril-rich fraction was isolated from the tauopathy mouse model. Protein levels of tau seeds were quantified by biochemical methods. Morphologies of tau seeds were investigated by AFM. Tau seeds were transfected into GFP-P301L-hu-tau expressing cells, and inoculated into P301L-hu-tau expressing mouse brains. When tau seeds were transfected into cells, intracellular tau inclusions were dose-dependently generated.Inoculation of tau seeds into mouse brains reproducibly induced tau deposits.AFM analysis revealed filamentous structures.The induction of tau aggregates by P301L-K18 seeds was less efficient than by brain-derived tau seeds.We established both in cell and in vivo tau seeding system. | | 7月8日（土） 12:50-13:50 ポスター会場①
3P⑦-3
遠志成分sibiricose A5によるアルツハイマー病モデルマウスの記憶改善作用の機序の解明
Mechanisms of sibiricose A5, a constituent of Polygalae Radix, for recovery of memory in Alzheimer's disease model mice
久保山 友晴1, 荒毛 優太1, 塘 健太1, 南雲 美咲2, 小湊 誠也2, 東田 千尋2
1. 第一薬科大 薬 生薬学, 2. 富山大 和漢研 神経機能学
Tomoharu Kuboyama1, Yuta Arake1, Kenta Tsutsumi1, Misaki Nagumo2, Seiya Kominato2, Chihiro Tohda2
1. Lab. of Pharmacognosy, Faculty of Pharmacy, Daiichi Univ. of Pharmacy, Fukuoka, Japan
Polygalae Radix (PR) is traditionally used for dementia. Extracts of PR reportedly improved memory in elderly human and dementia mouse models. We previously found that the PR extract induced axonal growth in amyloid β (Aβ)-treated neuron culture, and increased anti-inflammatory M2 microglia. These effects might contribute to memory recovery in the mouse models. In this study, we identified an active constituent in the PR extract and analyzed mechanisms of it.After oral administration of the PR extract to mice, sibiricose A5 (SA5) was detected in the brains. SA5 at 10 μM significantly induced axonal growth in Aβ-treated neuron culture. In cultured microglia, Aβ increased inflammatory M1 microglia. After that, SA5 at 1 nM tended to increase M2 microglia but not significant. Continuous intracerebroventricular injection of SA5 at 10 μM significantly improved memory impairment in 5XFAD Alzheimer’s disease model mice, but SA5 at 1 nM did not. SA5 injection at 10 μM significantly decreased degenerated axons in the perirhinal cortex of 5XFAD mice. DARTS analysis showed that RACK1 was a direct binding candidate with SA5. Knockdown of RACK1 diminished the axonal growth activity of SA5 in cultured neurons.Above results indicate that SA5 acts on neurons rather than microglia, induces axonal growth, and then recovers memory in 5XFAD mice. SA5 probably induced axonal growth via RACK1. | | 7月8日（土） 12:50-13:50 ポスター会場①
3P⑦-4
細胞外小胞によるトランスサイレチンアミロイドの沈着
Extracellular vesicles contribute to the metabolism of transthyretin amyloid in hereditary transthyretin amyloidosis
河原 裕憲1,2, 山口 浩輝3, 古寺 哲幸2, 多田 康剛1,3, 小野 賢二郎3, 山田 正仁4, 華山 力成1,2
1. 金沢大学 医薬保健研究域医学系 免疫学, 2. 金沢大学 ナノ生命科学研究所, 3. 金沢大学 医薬保健研究域医学系 脳神経内科学, 4. 九段坂病院
Hironori Kawahara1,2, Hiroki Yamaguchi3, Noriyuki Kodera2, Yasutake Tada1,3, Kenjiro Ono3, Masahito Yamada4, Rikinari Hanayama1,2
1. Dept. of Immunology, Graduate School of Medical Sciences, Kanazawa Univ., Kanazawa, Japan, 2. WPI Nano Life Science Institute (NanoLSI), Kanazawa Univ., Kanazawa, Japan, 3. Depart. of Neurology, Graduate School of Medical Sciences, Kanazawa Univ., Kanazawa, Japan, 4. Kudanzaka Hospital, Tokyo, Japan
Hereditary (variant) transthyretin amyloidosis (ATTRv amyloidosis), which is caused by variants in the transthyretin (TTR) gene, leads to TTR amyloid deposits in multiple organs and various symptoms such as limb ataxia, muscle weakness, and cardiac failure. Interaction between amyloid proteins and extracellular vesicles (EVs), which are secreted by various cells, is known to promote the clearance of the proteins, but it is unclear whether EVs are involved in the formation and deposition of TTR amyloid in ATTRv amyloidosis. To clarify the relationship between ATTRv amyloidosis and EVs, serum-derived EVs were analyzed. In this study, we showed that cell-derived EVs are involved in the formation of TTR amyloid deposits on the membrane of small EVs, as well as the deposition of TTR amyloid in cells. Human serum-derived small EVs also altered the degree of aggregation and deposition of TTR. Furthermore, the amount of TTR aggregates in serum-derived small EVs in patients with ATTRv amyloidosis was lower than that in healthy controls. These results indicate that EVs contribute to the metabolism of TTR amyloid, and suggest that TTR in serum-derived small EVs is a potential target for future ATTRv amyloidosis diagnosis and therapy. | | 7月8日（土） 12:50-13:50 ポスター会場①
3P⑦-5
口腔内炎症のパーキンソン病発症に及ぼす影響
Role of oral inflammation in the pathogenesis of Parkinson disease
永井 雅代1, 平山 正昭2, 直井 信1, 丸山 和佳子1
1. 愛知学院大学心身科学部健康栄養学科, 2. 名古屋大学院医学系研究科 総合保健学専攻 オミックス医療科学
Masayo Shamoto-Nagai1, Masaaki Hirayama2, Makoto Naoi1, Wakako Maruyama1
1. Dept. of Health and Nutrition, Fac. of Psycological & Physical Science, Aichi Gakuin University, Aichi, Japan, 2. Dept. of pathophysiol. Lab. Sci., Nagoya Univ. Graduate School of Medicine, Nagoya, Japan
Gastrointestinal system is gathering attention as the pathogenetic site of Parkinson disease (PD). The oral cavity is the most rostral part of the enteric canal but its role in PD has not been fully elucidated. The activity of salivary myeloperoxidase (MPO), which produces chloro-radicals to increase oxidative stress, was found to be an early biomarker of oral inflammation. Recently, we found salivary MPO activity increased in PD patients compared to control. To find out the factors relating oral inflammation, the effect of saliva from PD patients and control on the MPO activity was examined in vitro.
Materials and MethodsSaliva samples obtained from 14 PD patients and 20 healthy controls, were used. Authentic MPO enzyme were purchased from Sigma. The activity of MPO was determined using the MPO activity kit (Cayman). The study protocol was approved by Nagoya University Ethics Committee. (Authorization number: 8277)
ResultsAmong 14 saliva samples obtained from PD patients, 6 (30 %) decreased and 4 (28 %) increased the authentic MPO activity in vitro, significantly. In contrast, among 20 control saliva samples, 2 (10 %) decreased and 8 (40 %) increased authentic MPO activity.
ConclusionExistence of intrinsic factors regulating the activity of MPO was indicated in human saliva. The precise mechanism of increased oral inflammation in PD should be investigated further. | | | |
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