The aggregation and accumulation of alpha-synuclein (aSyn) fibrils results in histopathological inclusions calledLewybodiesandLewyneuritesandisobservedinseveralneurodegenerativedisorders.InParkinson?s disease(PD),thisculminatesinthedegenerationofdopaminergicneuronsinthesubstantianigraandsevere motor impairment. Emerging findings suggest that PD may have a prodromal phase characterized by non- motorsymptomssuchasgastrointestinaldisturbances.Thus,itishypothesizedthatpathologicaSynmightfirst accumulate in peripheral tissue before propagating to the brain where it precipitates PD pathology. This is supported by research that shows that aSyn fibrils are capable of interneuronal transport and can seed the formation of additional fibrils from endogenous aSyn. The goal of this proposal is to provide me with training in advanced techniques to interrogate peripheral nervous systems in mice. I will use these techniquestotestthehypothesisthatpathologicaSynpropagatesfromentericneuronsinthegutto the brain via the vagus nerve in an age- and activity-dependent manner, eventually damaging the dopaminergicsystemthatcoordinatesmovement.TovisualizeaSynfibrils,entericpopulations,andnerve tractsinhighresolution,IwillusetheCLARITYtissueclearingmethoddevelopedinourlabthatrenderswhole organs and organisms optically transparent and macromolecule permeable. I will also use novel quantitative measures to analyze large three-dimensional datasets. I will use a novel adeno associated virus capsid that hasincreasedaffinityforperipheralneuronstodeliverconstructstoneuronsandnervesintheentericnervous system. I will use whole cell patch clamp recordings to determine the effect of aSyn fibrils on enteric neuron electrophysiology and neurotransmission. Lastly, I will use optogenetics to explore an activity-dependent mechanism of aSyn uptake and release. Upon completion, the experiments detailed in this proposal will contributetoourunderstandingofpathologicaSynformationinthegutandtheirpropagationtothebrain,and willbekeyindevelopingnoveldiagnosticandtherapeuticstrategiesforPD.

Public Health Relevance

The proposed project will explore how Parkinson?s disease pathology may originate in the enteric nervous systemofthegut.Inparticular,thisworkwillinvestigatethepropagationoftoxicalpha-synucleinfibrilsfromthe peripheralnervoussystemtothebrainviathevagusnerve.Resultsfromthisworkwillhelpthedevelopmentof diagnostictoolsandtherapeuticinterventionsagainstpathologicalpha-synucleinforParkinson?sdisease.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
5F32AG054101-02
Application #
9459736
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
St Hillaire-Clarke, Coryse
Project Start
2017-03-01
Project End
2020-02-29
Budget Start
2018-03-01
Budget End
2019-02-28
Support Year
2
Fiscal Year
2018
Total Cost
Indirect Cost
Name
California Institute of Technology
Department
Type
Schools of Arts and Sciences
DUNS #
009584210
City
Pasadena
State
CA
Country
United States
Zip Code
91125