Developing a model for studying the role of Amyloid-beta in Nothobranchius furzeri (Actinopteri; Cypriniformes) neurodegeneration

master's thesis

• Title (croatian): Razvoj modela za analizu uloge proteina amiloid-beta u procesu neurodegeneracije u vrste Nothobranchius furzeri (Actinopteri; Cyprinodontiformes)
• Author: Mihaela Mihaljević
• Mentor: Dario Riccardo Valenzano (mentor)
• Mentor: Petra Korać (komentor)
• Committee member: Petra Korać (predsjednik povjerenstva)
• Committee member: Biljana Balen (član povjerenstva)
• Committee member: Inga Urlić (član povjerenstva)
• Committee member: Maja Matulić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2022-09-20, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

The Alzheimer’s disease (AD) is the most prevalent form of dementia, majorly affecting
elderly population. Despite extensive research related to the AD, the lack of knowledge about
exact causes imposes an obstacle in the development of effective treatments of the disease. One
of the main hallmarks of AD is the accumulation of amyloid-β peptides in the brain, but the
mechanism underlying it is unknown. The African turquoise killifish (Nothobranchius furzeri)
has been used to study several hallmarks of neurodegeneration, such as general cognitive
decline, neuronal degeneration, neuroinflammation, ongoing oxidative stress and accumulation
of α-synuclein in the brain. This study aimed to investigate accumulation of amyloid-β in the
aging turquoise killifish brain, as well as detect differences in age-dependent brain
degeneration between turquoise killifish and zebrafish (Danio rerio). Fluorescent
immunohistochemistry was utilized on the cross-sections of brain tissue. The results show that
turquoise killifish displays age-dependent accumulation of amyloid-β in the brain. Moreover,
turquoise killifish undergoes brain atrophy, astrogliosis and loss of neuronal density, while
zebrafish shows lower extent of age-related brain pathologies. This study aimed to create
CRISPR/Cas9-mediated mutants of amyloid-β precursor protein for further studying of AD.
The research resulted in a successful mutation of one out of two paralogue genes in the
turquoise killifish.

Abstract (croatian)

Alzheimerova bolest najzastupljeniji je oblik demencije koji većinom pogađa stariju
populaciju. Unatoč opsežnim istraživanjima same bolesti, točni uzroci nastanka i dalje su
nepoznati, što dodatno otežava razvoj učinkovitih terapija. Jedno od glavnih obilježnja
Alzheimerove bolesti je nakupljanje peptida amiloid-β u mozgu, no mehanizam nastanka nije
poznat. U zadnje vrijeme, riba vrste Nothobranchius furzeri uvelike se koristi za istraživanje
nekoliko obilježja procesa neurodegeneracije mozga, poput smanjenja kognitivnih
sposobnosti, degeneracije neurona, upalnih procesa u mozgu, oksidativnog stresa te
nakupljanja proteina α-sinuklein u tkivu mozga. Cilj ovog istraživanja bio je istražiti
nakupljanje peptida amiloid-β u procesu starenja mozga N. furzeri, kao i uočiti razlike između
mozga N. furzeri i zebrice (Danio rerio). Za istraživanje je korištena fluorescentna
imunohistokemija na presjecima moždanog tkiva. Rezultati pokazuju da u mozgu N. furzeri
dolazi do nakupljanja peptida amiloid-β tijekom starenja. Također, mozak N. furzeri atrofira,
prolazi kroz proces astroglioze te pokazuje smanjenu gustoću neurona, dok zebrica tijekom
starenja pokazuje blažu patologiju mozga. Nadalje, cilj istraživanja bio je pomoću platforme
CRISPR/Cas9 mutirati gen za prekursor proteina amiloid-β, koji će poslužiti za daljnje
istraživanje Alzheimerove bolesti. Istraživanje je rezultiralo utišavanjem jednog od dva
paraloga ovog gena u N. furzeri.

• Keywords: APP; astrogliosis; neuronal loss; CRISPR/Cas9 mutants
• Keywords (croatian): APP; astroglioza; gubitak neurona; mutant CRISPR/Cas9 (74 stranica; 16 slika; 7 tablica; 155 literaturnih navoda; jezik izvornika: engl
• Language: croatian
• URN:NBN: urn:nbn:hr:217:252651
• Study programme: Title: Molecular Biology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra molekularne biologije (magistar/magistra molekularne biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2024-09-20
• Created on: 2022-10-13 10:30:21