京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22001号 / 医博第4515号 / 新制||医||1038(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 井上 治久, 教授 林 康紀, 教授 高橋 淳 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 新制・課程博士 / 博士(医学) / 甲第23089号 / 医博第4716号 / 新制||医||1050(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 高橋 淳, 教授 浅野 雅秀, 教授 伊佐 正 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Auch wenn die Ätiopathogenese von Morbus Parkinson bis heute nicht vollständig geklärt ist, scheint α-Synuclein (α-Syn) eine zentrale Rolle zu spielen. Die Entdeckung als genetische Ursache der Erkrankung, als Hauptbestandteil der Lewy-Körper (LK) und seine Assoziation mit verschiedenen anderen potenziellen ätiologischen Faktoren verdeutlichen dies. Bei Ratten und Affen führte eine AAV1/2-vermittelte Überexpression von A53T-α-Syn zu einer Degeneration dopaminerger Neurone in der Substantia nigra (SN), einem striatalen dopaminergen Defizit sowie Verhaltensauffälligkeiten. In Anbetracht bestimmter Vorteile der Mausspezies, war es das Ziel dieser Dissertation - die im Rahmen eines kollaborativen Projektes mit dem Toronto Western Research Institut in Ontario, Kanada entstanden ist - dieses auf AAV1/2-A53T-α-Syn basierende Parkinson-Modell auf Mäuse zu übertragen. Dazu wurde AAV1/2-A53T-α-Syn oder leerer AAV1/2-Vektor in einer Dosis von 1,5 µl mit einer Konzentration von 5,16 x 10^12 gp/ml stereotaktisch einseitig in die rechte SN von C57BL/6-wt-Mäusen injiziert. Über einen Zeitraum von 11 Wochen wurden verschiedene Verhaltensexperimente durchgeführt und die beiden Versuchstiergruppen miteinander verglichen. Post-mortem erfolgten verschiedene immunhistochemische Untersuchungen. Es konnte gezeigt werden, dass die einseitige Injektion von AAV1/2-A53T-α-Syn in die SN bei Mäusen eine weit verbreitete Überexpression von A53T-α-Syn in dopaminergen Neuronen der SN induzierte, die innerhalb von 10 Wochen zu signifikanten frühen und persistierenden motorischen Verhaltensauffälligkeiten, nigrostriataler Degeneration und Entwicklung einer Lewy-ähnlichen Pathologie führte. Durch die Generierung und Charakterisierung dieses neuen Parkinson-Mausmodells, das klinische und histopathologische Merkmale der menschlichen Erkrankung widerspiegelt, besteht nun die Möglichkeit es weiterzuentwickeln und z.B. auf transgene Mäuse zu übertragen, um u.a. molekulare Mechanismen der Parkinson-Krankheit zu entschlüsseln und präklinische Tests von krankheitsmodifizierenden Therapien durchzuführen. / Although the etiopathogenesis of Parkinson’s disease (PD) has not been fully elucidated to date, α-synuclein (α-syn) seems to play a central role. Its discovery as a genetic cause of the disease, as the major component of the Lewy bodies (LB) and its association with other potential etiological factors illustrate this. In rats and monkeys, AAV1/2-mediated overexpression of A53T-α-syn resulted in degeneration of dopaminergic neurons of the substantia nigra (SN), a striatal dopaminergic deficit and behavioral deficits. Given certain advantages of the mouse species, the aim of this doctoral thesis - which was part of a collaborative project with the Toronto Western Research Institute in Ontario, Canada - was to transfer this AAV1/2-A53T-α-syn based PD model to mice. For this purpose, 1.5 µl of AAV1/2-A53T-α-syn or AAV1/2 empty vector at a concentration of 5.16 x 10^12 gp/ml were stereotactically injected unilaterally into the right SN of C57BL/6-wt-mice. Several behavioral experiments were performed over a period of 11 weeks and the two groups of mice were compared. Post-mortem measures included different immunohistochemical studies. It was shown that unilateral injection of AAV1/2-A53T-α-syn into the mouse SN induced a widespread overexpression of A53T-α-syn in dopaminergic SN neurons, that led to significant early and persistent motor deficits, nigrostriatal degeneration and development of Lewy-like pathology within 10 weeks. By generating and characterizing this novel PD mouse model, which reflects clinical and histopathological hallmarks of human PD, there is now the opportunity to further develop it and to transfer it e.g. to transgenic mice for unravelling molecular mechanisms of PD and preclinical testing of disease modifying therapies.

京都大学 / 新制・論文博士 / 博士(医学) / 乙第13463号 / 論医博第2250号 / 新制||医||1055(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 高橋 淳, 教授 稲垣 暢也, 教授 萩原 正敏 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM

No description available.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19178号 / 医博第4020号 / 新制||医||1010(附属図書館) / 32170 / 京都大学大学院医学研究科医学専攻 / (主査)教授 髙橋 淳, 教授 渡邉 大, 教授 村井 俊哉 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Parkinson’s disease is a neurodegenerative disorder characterized by the loss of motor skills and cognitive impairment. The hallmark of this disease is the presence of Lewy bodies in the substantia nigra of the brain, where the accumulation of alpha-synuclein amyloid fibrils lead to the death of dopaminergic neurons. Understanding the factors influencing AS aggregation and developing effective strategies for its inhibition is of paramount importance for developing potential therapeutic interventions. Previous studies suggest that flavonoids in green and black tea have neuroprotective properties that decrease the fibrillization rate of AS. This thesis investigates the inhibitory effects of two flavonoids coming from green and black tea, namely: EGCG, TFDG, and HSA on AS aggregation, shedding light on their potential as therapeutic candidates. The study employed a combination of biochemical and biophysical experimental techniques to elucidate the inhibitory mechanisms of EGCG, TFDG, and HSA on AS aggregation. Initial experiments involved the characterization of AS fibrillation kinetics using ThT assays, TEM, and CD. Results revealed that flavonoids exhibited similar inhibitory effects on AS aggregation, with more than 90% inhibitory potency. Interestingly, when aggregated AS was exposed to EGCG or TFDG, the amyloid fibrils changed conformation and formed non-toxic amorphous oligomers. The 13C-detected NMR experiments, adapted to probe the AS dynamic conformation and interactions at the atomic level at physiologically relevant conditions, further provided insights into the binding interactions between flavonoids and AS, revealing interaction with hydrophobic residues involved in the inhibition process. Furthermore, the role of HSA, a major protein component of the blood plasma, in modulating α-synuclein aggregation in the presence of tea-derived flavonoids was investigated. The study demonstrated, in line with the previous reports, that HSA can significantly suppress AS fibrillation, and moreover, the presence of HSA further enhances the flavonoids’ inhibitory effect. My findings provide valuable atomic level mechanistic insights into the inhibitory effects of EGCG and TFDG on alpha-synuclein aggregation. The comprehensive spectroscopic and biophysical investigation provides a solid foundation for further developing flavonoid-based inhibitors, subsequently drug candidates blocking the AS toxic oligomers formation and aggregation.

New models in which aging-related neurodegeneration more closely resembling the combination of pathologies that develop in aging humans, are needed. The fish Nothobranchius, which naturally develops such pathologies over the course of its short lifespan, is one such model. This review compares the lifespans and pathologies of different Nothobranchius strains to those of current vertebrate models of aging. Furthermore, existing data pertaining to neurodegeneration in these fish is discussed in the context of their reported neuropathologies, along with open questions related to mammalian chronopathologies. Specifically, the evidence for a Parkinson’s disease-like pathology is discussed. Neurogenesis and age-related changes therein are discussed in the context of siRNA and neurodegeneration. We also discuss changes in the expression of neuropeptide Y in relation to the brain-gut axis and how these change with age. Age-related behavioral changes are discussed, along with the assays used in their evaluation. Genetic discoveries are outlined and discussed with a view on DJ-1/NRF2 signaling in N. furzeri, and insights gained from comparative genomics and siRNA studies. Finally, research focus areas are highlighted, and a case is made for the utility of these fish in the study of aging-related neurodegeneration, and to screen for environmental risk factors of aging-related neuropathology.

京都大学 / 新制・論文博士 / 博士(医学) / 乙第13525号 / 論医博第2271号 / 新制||医||1062(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 井上 治久, 教授 大森 孝一, 教授 古川 壽亮 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 新制・課程博士 / 博士(医学) / 甲第23757号 / 医博第4803号 / 新制||医||1056(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 井上 治久, 教授 岩田 想, 教授 上杉 志成 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM