|Name||Miss Natasha Ram|
|Organization or Institution||University of South Florida|
|Topic||Biochemistry / Chem Bio.|
Withaferin A (WA) reduces disease associated variants of alpha-synuclein in cellular models
Natasha Ram, Malathi Narayan, Geeta Iyer, Khawla Benyamine, Nicholas Johnson, Marai Roque Solares, Christina Veliz, George Padilla, Andres Perez, Alaina Branford, Jennifer L. Drew-Bear Quintanilla, Zahra Radpasand, Nidhi Sama, Sonal Sian, Kimberly Smythe, and Umesh Jinwal
University of South Florida
Alpha synuclein protein is a major component of abnormal filaments in Parkinson’s disease (PD) and many other neurodegenerative diseases collectively called synucleopathies. It is predominantly found as Lewy bodies and Lewy neurites in nerve and glial cells. Increase of alpha synuclein inclusions in cytoplasm have been observed in PD and Dementia with Lewy bodies (DLB). Hence, we aimed to find a novel synuclein-targeting drug that can be used for treatment of PD and other synucleinopathies. Transfectants of M17 neuroblastoma cells that expressed alpha synuclein variants were treated with withaferin A or a vehicle control, for 24 hours. Western blotting was used to analyze cell lysates post-treatment. To determine how WA regulated the alpha-synuclein pathways, autophagy and proteosomal pathway inhibitors were used in the treatments. Knockdown studies were performed using siRNA. Localization studies performed using immunofluorescence technique. WA treatment led to reduction of wildtype or A30P, E46K and A53T point mutants of α-synuclein. Proteasomal and autophagy pathway inhibitors study showed WA reduces α-synuclein through synergistic action of both pathways. Immunofluorescence analysis showed WA treatment leads to nuclear localization of α-synuclein. In addition, knockdown studies showed p62 protein’s involvement in WA mediated alpha-synuclein reduction. Utilizing cellular models of synucleinopathy, we found WA treatment leads to significant reduction in alpha-synuclein. Furthermore, we found p62 protein may play a role in WA mediated reduction of alpha-synuclein. Overall, our data suggests Withaferin A could serve as a potential drug for treatment of synucleopathies.