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Tuning the Balance between Fibrillation and Oligomerization of ?-Synuclein in the Presence of Dopamine.

ABSTRACT: The aggregates of ?-synuclein bear a close connection with Parkinson's disease, which is largely characterized by the loss of the dopaminergic neurons. Dopamine promotes the formation of undesirable sodium dodecyl sulfate (SDS)-resistant oligomers of ?-synuclein. In this study, we have shown that the inhibition of fibrillation by an additive may not always be the ultimate deciding factor in the context of its potential as a successful additive. Copper promotes the fibrillation of ?-synuclein in buffer alone but inhibits the formation of SDS-resistant oligomers in the presence of dopamine. Glycerol, on the other hand, increases the population of such dopamine-mediated SDS-resistant oligomers. We speculate such an effect to be a manifestation of the distinct oxidation pathway of dopamine in the presence of copper.

SUBMITTER: Saha S

PROVIDER: S-EPMC6217689 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Tuning the Balance between Fibrillation and Oligomerization of α-Synuclein in the Presence of Dopamine.

Saha Shivnetra S Khan Mohammad Ashhar Iqbal MAI Mudhara Deepak D Deep Shashank S

ACS omega 20181026 10

The aggregates of α-synuclein bear a close connection with Parkinson's disease, which is largely characterized by the loss of the dopaminergic neurons. Dopamine promotes the formation of undesirable sodium dodecyl sulfate (SDS)-resistant oligomers of α-synuclein. In this study, we have shown that the inhibition of fibrillation by an additive may not always be the ultimate deciding factor in the context of its potential as a successful additive. Copper promotes the fibrillation of α-synuclein in ...[more]

PMID: 30411062

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