Biology subjects

Redding-Ochoa, J.

Publications and source records attributed to Redding-Ochoa, J..

2 recordsLinked to original sources

bioRxiv2022

Surface phenotyping and quantitative proteomics reveal differentially enriched proteins of brain-derived extracellular vesicles in Parkinson's disease

Extracellular vesicles (EVs) are produced by all cell types and are found in all tissues and biofluids. EV proteins, nucleic acids, and lipids are a "nano-snapshot" of the parent cell that may be used for novel diagnostics of various diseases, including neurodegenerative disorders. Currently, diagnosis of the most common neurodegenerative movement disorder, Parkinsons disease (PD), relies on manifestations of late-stage progression, which may furthermore associate with other neurodegenerative diseases such as progressive supranuclear palsy (PSP). Here, we profiled surface markers and other protein contents of brain-derived extracellular vesicles (bd-EVs) from PD (n= 24), PSP (n=25) and control (n=24). bdEVs displayed tetraspanins and certain microglia, astrocyte, and neuron markers, while quantitative proteomics revealed enrichment of several proteins in PD vs. control and/or PSP, including clathrin heavy chain 1 and 14-3-3 protein gamma. This characterization of EVs in the source tissue provides insights into local dynamics as well as biomarker candidates for investigation in peripheral fluids.

neuroscience↗

bioRxiv2022

Enhanced mTORC1 signaling and Protein Synthesis in Parkinson Disease Pathogenesis

Pathologic -syn destabilizes the TSC 1 and 2 complex leading to mTORC1 activation, enhanced protein translation and neurodegeneration in PD. AbstractPathological -synuclein (-syn) plays an important role in the pathogenesis of -synucleinopathies such as Parkinsons disease (PD). Disruption of protein homeostasis is thought be central to PD pathogenesis, however the molecular mechanism of this deregulation is poorly understood. Here we report that pathologic -syn binds to tuberous sclerosis protein (TSC) 2 and destabilizes the TSC1-TSC2 complex leading to activation of the mechanistic target of rapamycin (mTOR) complex 1 (mTORC1) and enhanced mRNA translation. Dopamine neuron loss, behavioral deficits and aberrant biochemical signaling in the -syn preformed fibril (PFF) and Drosophila -syn transgenic models of pathologic -syn induced degeneration were attenuated by genetic and pharmacologic inhibition of mTOR and protein translation. Our findings establish a potential molecular mechanism by which pathologic -syn activates mTORC1 leading to enhanced protein translation and concomitant neurodegeneration in PD.

neuroscience↗