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Rojas, J. C.

Publications and source records attributed to Rojas, J. C..

2 recordsLinked to original sources

Large-scale cerebrospinal fluid proteomics identifies diagnostic biomarker candidates across the clinico-pathological continuum of frontotemporal lobar degeneration

Frontotemporal lobar degeneration (FTLD), predominantly comprised of tau and TDP-43 proteinopathies, is a common cause of early-onset dementia. Biomarkers that reliably classify FTLD subtypes are limited, thereby hindering in-vivo diagnosis and clinical trial stratification. We conducted large-scale, multi-platform cerebrospinal fluid proteomics in 566 individuals, including 274 FTLD-spectrum (48 autopsy-confirmed FTLD-TDP, 90 autopsy-confirmed FTLD-tau), 171 Alzheimers disease, and 95 controls. In neuropathological subtype contrasts, elevated matrix metalloproteinase MMP10 classified Picks disease (PiD) versus other subtypes with near-perfect accuracy across proteomic platforms. We further validated CSF MMP10 as a potential PiD diagnostic biomarker via a targeted immunoassay in an independent, autopsy-confirmed FTLD cohort. Post-synaptic proteins HOMER1 and DLG4 exhibited elevations across FTLD-TDP subtypes (A, B, and C) versus FTLD-tau. Network analysis identified RNA metabolism and pro-inflammatory signatures in FTLD-TDP, and cytoskeletal and heat shock signatures in progressive supranuclear palsy. These findings reveal candidate diagnostic biomarkers and proteomic pathways underlying FTLD clinico-pathological heterogeneity.

neuroscience↗

Tau Secretion and Propagation Is Regulated by p300/CBP via Autophagy-Lysosomal Pathway in Tauopathy

The trans-neuronal propagation of tau has been implicated in the progression of tau-mediated neurodegeneration. Tau secretion from neurons is the first step in tau transmission, but little is known about the cellular mechanism. Here, we report that p300/CBP, the lysine acetyltransferase that acetylates tau and regulates its homeostasis and toxicity, serves as a key regulator of tau secretion by inhibiting the autophagy-lysosomal pathway (ALP). Increased p300/CBP activity was associated with impaired function of this pathway in a tau transgenic mouse model. p300/CBP hyperactivation increased tau secretion by blocking autophagic flux. Conversely, inhibiting p300/CBP genetically or pharmacologically promoted autophagic flux, and reduced tau accumulation, tau secretion, and tau propagation in fibril-induced tau spreading models in vitro and in vivo. Our findings show that p300/CBP-induced impairment in the ALP underlies excessive unconventional secretion and pathogenic spread of tau.

neuroscience↗