{"created":"2025-06-12T00:08:55.108514+00:00","id":2000340,"links":{},"metadata":{"_buckets":{"deposit":"44b536f7-634a-41eb-8ecb-79ebe489279e"},"_deposit":{"created_by":20,"id":"2000340","owner":"20","owners":[20],"pid":{"revision_id":0,"type":"depid","value":"2000340"},"status":"published"},"_oai":{"id":"oai:muroran-it.repo.nii.ac.jp:02000340","sets":["41:227"]},"author_link":[],"item_1716854901627":{"attribute_name":"日付","attribute_value_mlt":[{"subitem_date_issued_datetime":"2026-03-01","subitem_date_issued_type":"Available"}]},"item_81_date_granted_17":{"attribute_name":"学位授与年月日","attribute_value_mlt":[{"subitem_dategranted":"2025-03-24"}]},"item_81_degree_grantor_10":{"attribute_name":"学位授与機関","attribute_value_mlt":[{"subitem_degreegrantor":[{"subitem_degreegrantor_language":"ja","subitem_degreegrantor_name":"室蘭工業大学"},{"subitem_degreegrantor_language":"en","subitem_degreegrantor_name":"Muroran Institute of Technology"}],"subitem_degreegrantor_identifier":[{"subitem_degreegrantor_identifier_name":"10103","subitem_degreegrantor_identifier_scheme":"kakenhi"}]}]},"item_81_degree_name_11":{"attribute_name":"学位名","attribute_value_mlt":[{"subitem_degreename":"博士（工学）","subitem_degreename_language":"ja"}]},"item_81_description_7":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"タンパク質のミスフォローディングと凝集は、アルツハイマー病（AD）、パーキンソン病\n（PD）、プリオン病、2 型糖尿病（T2DM）を含む多くの神経変性疾患の特徴である。これらの\n疾患の中で、T2DM は慢性的な代謝疾患であり、高血糖症（長期間にわたる血漿中のグルコ\nース濃度の上昇）や標的組織でのインスリン抵抗性を伴う。現在、T2DM の発症率は世界的\nに流行レベルに達しており、その治療は非常に重要である。アミリンは、T2DM の治療標的\nとして認識されている。しかし、アミリン凝集のメカニズムが明らかでないため、T2DM の\n治療が妨げられている。\n本研究では、量子ドット（QD）イメージング法を用いてアミリンのin vitro 凝集プロセ\nスを解析した。QD 蛍光イメージングの結果、100 μM のアミリン存在下で、12 時間のイン\nキュベーション後に凝集体が出現し始め、24 時間後には多数の凝集体が形成されることが\n明らかになった。一方、50 μM のアミリンでは、12 時間のインキュベーション後には凝集\n体は形成されず、24 時間後に多数の凝集体が観察された。共焦点レーザー顕微鏡観察によ\nり、これらの凝集体が三次元的に堆積していることが確認された。透過型電子顕微鏡（TEM）\n観察では、アミリンがin vitro でミスフォールドしたフィブリルとして存在し、QD が均一\nにアミリンフィブリルに結合していることが明らかになった。さらに、微量ハイスループッ\nトスクリーニング（MSHTS）システムを用いて、ポリフェノールであるロスマリン酸（RA）\nが852.8 μM の50%効果濃度でアミリン凝集を阻害することを見出した。\nIn vivo 実験では、アミリンをゼブラフィッシュの胚にマイクロインジェクションし、異\nなる濃度のRA に曝露した。蛍光イメージングにより、ゼブラフィッシュ内のアミリン凝集\nをモニタリングし、蛍光強度を凝集の程度の指標とした。さらに、アミリン凝集阻害の生理\n学的効果を評価するために、受精後 120 時間 (hpf) のゼブラフィッシュ幼生に対して行\n動分析を実施した。その結果、RA への曝露によりゼブラフィッシュの蛍光強度が低下し、\nアミリン凝集が減少することが確認された。さらに、RA はアミリンフィブリル化毒性に関\n連する行動変化を軽減し、RA がin vivo でのアミリン凝集による毒性を効果的に緩和する\nことを示唆した。今後は、アミリン凝集阻害剤を幅広くスクリーニングし、in vitro およ\nび in vivo 試験を通じて、アミリン凝集体の形成、沈着、および毒性を抑制する作用メカ\nニズムをさらに探求する予定である。","subitem_description_language":"ja","subitem_description_type":"Abstract"},{"subitem_description":"Protein misfolding and aggregation are the hallmarks of many neurodegenerative\ndiseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD), and type\n2 diabetes mellitus (T2DM). Among these diseases, T2DM is a chronic metabolic\ndisease associated with hyperglycemia, elevated levels of glucose in plasma for\nprolonged periods, and insulin resistance in target tissues. Currently, the\nincidence of T2DM has reached epidemic proportions globally. Therefore, the\ntreatment of T2DM is of great importance. Amylin has been recognized as a\ntherapeutic target for T2DM management. The unclear mechanism of amylin aggregation\nhas hindered the treatment of T2DM.\nIn this study, I analyzed the in vitro aggregation process of amylin using the\nquantum dot (QD) imaging method. QD fluorescence imaging revealed that in the\npresence of 100 μM amylin, aggregates appeared after 12 h of incubation, while a\nlarge number of aggregates formed after 24 h of incubation. In contrast, 50 μM\namylin did not form aggregates after 12 h of incubation but produced a large number\nof aggregates after 24 h. Confocal laser microscopy observations revealed that\nthese aggregates were deposited in three dimensions. Transmission electron\nmicroscopy (TEM) revealed that amylin existed as misfolded fibrils in vitro and\nthat QDs were uniformly bound to the amylin fibrils. In addition, using a\nmicroliter-scale high-throughput screening (MSHTS) system, I found that rosmarinic\nacid (RA) inhibited amylin aggregation at a half-maximal effective concentration\nof 852.8 μM.\nIn vivo, amylin was microinjected into zebrafish embryos and exposed to different\nconcentrations of RA. Fluorescence imaging was used to monitor amylin aggregation\nin the zebrafish, with fluorescence intensity serving as an indicator of the extent\nof aggregation. Additionally, behavioral analysis was performed on zebrafish larvae\nat 120 hours post-fertilization (hpf) to assess the physiological effects of amylin\naggregation inhibition. The results showed that exposure to RA reduced fluorescence\nintensity in zebrafish, indicating a decrease in amylin aggregation. Moreover, RA\nexposure alleviated behavioral changes associated with amylin fibrillation\ntoxicity, suggesting that RA effectively mitigates the toxicity induced by amylin\naggregation in vivo. In the future, I plan to screen a broader range of amylin\naggregation inhibitors for in vitro and in vivo testing to further explore the\nmechanism of action in inhibiting the formation, deposition, and toxicity of amylin\naggregates.","subitem_description_language":"en","subitem_description_type":"Abstract"}]},"item_81_dissertation_number_13":{"attribute_name":"学位授与番号","attribute_value_mlt":[{"subitem_dissertationnumber":"甲第544号"}]},"item_81_text_12":{"attribute_name":"学位の種別","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"課程博士"}]},"item_81_text_14":{"attribute_name":"報告番号","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"甲第544号"}]},"item_81_text_15":{"attribute_name":"学位記番号","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"博甲第544号"}]},"item_81_text_16":{"attribute_name":"研究科・専攻","attribute_value_mlt":[{"subitem_text_language":"ja","subitem_text_value":"工学研究科"}]},"item_81_version_type_24":{"attribute_name":"著者版フラグ","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_970fb48d4fbd8a85","subitem_version_type":"VoR"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"embargoed access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_f1cf"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorAffiliations":[{"affiliationNames":[{"affiliationName":"室蘭工業大学","affiliationNameLang":"ja"},{"affiliationName":"Muroran Institute of Technology","affiliationNameLang":"en"}]}],"creatorNames":[{"creatorName":"Xiaoyu, Yin","creatorNameLang":"en"}],"familyNames":[{"familyName":"Xiaoyu","familyNameLang":"en"}],"givenNames":[{"givenName":"Yin","givenNameLang":"en"}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2026-03-01"}],"filename":"A544.pdf","filesize":[{"value":"8 MB"}],"format":"application/pdf","url":{"objectType":"fulltext","url":"https://muroran-it.repo.nii.ac.jp/record/2000340/files/A544.pdf"},"version_id":"3152c8fe-95a0-493a-9340-230cf1be3909"},{"accessrole":"open_access","date":[{"dateType":"Available","dateValue":"2025-06-12"}],"filename":"A544_summary.pdf","filesize":[{"value":"129 KB"}],"format":"application/pdf","url":{"objectType":"abstract","url":"https://muroran-it.repo.nii.ac.jp/record/2000340/files/A544_summary.pdf"},"version_id":"1e1f9dc3-bd75-43f1-b06d-a3b65257c0e7"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"doctoral thesis","resourceuri":"http://purl.org/coar/resource_type/c_db06"}]},"item_title":"Analyzing amylin aggregation inhibition through in vitro and in vivo fluorescence imaging","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Analyzing amylin aggregation inhibition through in vitro and in vivo fluorescence imaging","subitem_title_language":"en"},{"subitem_title":"in vitro およびin vivo 蛍光イメージングによるアミリン凝集阻 害の解析","subitem_title_language":"ja"}]},"item_type_id":"81","owner":"20","path":["227"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2025-06-12"},"publish_date":"2025-06-12","publish_status":"0","recid":"2000340","relation_version_is_last":true,"title":["Analyzing amylin aggregation inhibition through in vitro and in vivo fluorescence imaging"],"weko_creator_id":"20","weko_shared_id":-1},"updated":"2025-06-12T00:15:12.821378+00:00"}