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Pantelyat, A.

Publications and source records attributed to Pantelyat, A..

4 recordsLinked to original sources

Targeted α-Synuclein mRNA Degradation by PMO-Based RNA-Degrading Chimeras

-Synucleinopathies are devastating neurodegenerative diseases characterized by pathological accumulation of a neuronal protein, -synuclein (Syn). Lowering soluble Syn levels is a promising therapeutic strategy to limit aggregation and neurotoxicity, but directly targeting this protein is hindered by its intrinsically disordered structure and other factors, such as its conformational heterogeneity and intracellular drug delivery barriers. Consequently, increasing attention has been directed toward targeting the SNCA transcript, which encodes Syn. Here, we developed phosphorodiamidate morpholino oligonucleotide (PMO)-based RNA-degrading chimeras (RDCs) that selectively bind the 5' untranslated region of SNCA mRNA and recruit RNase L for targeted RNA degradation. Through the systematic evaluation of 10 RDCs, we identified and optimized 4-D1, which effectively reduced SNCA mRNA and Syn protein expression in HEK293T cells in an RNase L-dependent manner. 4-D1 lowered SNCA transcript and Syn protein levels in both primary cortical neurons from humanized SNCA mice and in human induced pluripotent stem cell-derived cortical neurons. This reduction prevented prion-like seeding induced by patient-derived Syn fibrils and protected neurons from fibril-induced cytotoxicity. Finally, in vivo studies confirmed the efficacy of 4-D1 in reducing Syn mRNA expression in humanized SNCA mice. These findings indicate that PMO-based RDCs may represent a promising therapeutic modality for -synucleinopathies. Significance StatementAbnormal aggregation of the neuronal protein -synuclein is central to Parkinsons disease and related disorders, yet therapeutic candidates that directly target this protein have yet to demonstrate efficacy. in clinical trials. We developed a new strategy that lowers -synuclein production at the RNA level using phosphorodiamidate morpholino oligonucleotide (PMO)-based RNA-degrading chimeras (RDCs). These molecules recruit a natural RNA-degrading enzyme to selectively destroy the RNA transcript encoding -synuclein. Our lead RDC reduced -synuclein levels in cultured cells, humanized mouse and human neurons, blocked -synuclein pathological aggregation, and protected neurons from toxicity. This study establishes RDCs as a promising therapeutic platform for Parkinsons disease and other neurodegenerative diseases driven by -synuclein.

biochemistry↗

Sex differences in the clinical manifestation of autosomal dominant frontotemporal dementia

INTRODUCTIONSex differences are apparent in neurodegenerative diseases, but have not been comprehensively characterized in frontotemporal dementia (FTD). METHODSParticipants included 337 adults with autosomal dominant FTD enrolled in the ALLFTD Consortium. Clinical assessments and plasma were collected annually for up to six years. Linear mixed-effects models investigated how sex and disease stage associated with longitudinal trajectories of cognition, function, and neurofilament light chain (NfL). RESULTSWhile sex differences were not apparent at asymptomatic stages, females showed more rapid declines across all outcomes in symptomatic stages compared to males. In asymptomatic participants, the association between baseline NfL and clinical trajectories was weaker in females versus males, a difference that attenuated in symptomatic participants. DISCUSSIONIn genetic FTD, females show cognitive resilience in early disease stages followed by steeper clinical declines later in disease. Baseline NfL may be a less sensitive prognostic tool for clinical progression in females with FTD-causing mutations.

neuroscience↗

Common variation at the LRRK2 locus is associated with survival in the primary tauopathy progressive supranuclear palsy

The genetic basis of variation in the rate of disease progression of primary tauopathies has not been determined. In two independent progressive supranuclear palsy cohorts, we show that common variation at the LRRK2 locus determines survival from motor symptom onset to death, possibly through regulation of gene expression. This links together genetic risk in alpha-synuclein and tau disorders, and suggests that modulation of proteostasis and neuro-inflammation by LRRK2 inhibitors may have a therapeutic role across disorders.

genetics↗

Genetic modifiers of risk and age at onset in GBA associated Parkinson disease and Lewy body dementia

Parkinsons disease (PD) is a genetically complex disorder. Multiple genes have been shown to contribute to the risk of PD, and currently 90 independent risk variants have been identified by genome-wide association studies. Thus far, a number of genes (including SNCA, LRRK2, and GBA) have been shown to contain variability across a spectrum of frequency and effect, from rare, highly penetrant variants to common risk alleles with small effect sizes. Variants in GBA, encoding the enzyme glucocerebrosidase, are associated with Lewy body diseases such as PD and Lewy body dementia (LBD). These variants, which reduce or abolish enzymatic activity, confer a spectrum of disease risk, from 1.4- to >10-fold. An outstanding question in the field is what other genetic factors that influence GBA-associated risk for disease, and whether these overlap with known PD risk variants.\n\nUsing multiple, large case-control datasets, totalling 217,165 individuals (22,757 PD cases, 13,431 PD proxy cases, 622 LBD cases and 180,355 controls), we identified 1,772 PD cases, 711 proxy cases and 7,624 controls with a GBA variant (p.E326K, p.T369M or p.N370S). We performed a genome-wide association study and analysed the most recent PD-associated genetic risk score to detect genetic influences on GBA risk and age at onset. We attempted to replicate our findings in two independent datasets, including the personal genetics company 23andMe, Inc. and whole-genome sequencing data. Our analysis showed that the overall PD genetic risk score modifies risk for disease and decreases age at onset in carriers of GBA variants. Notably, this effect was consistent across all tested GBA risk variants. Dissecting this signal demonstrated that variants in close proximity to SNCA and CTSB (encoding cathepsin B) are the most significant contributors. Risk variants in the CTSB locus were identified to decrease mRNA expression of CTSB. Additional analyses suggest a possible genetic interaction between GBA and CTSB and GBA p.N370S neurons were shown to have decreased Cathepsin B expression compared to controls. These data provide a genetic basis for modification of GBA-associated PD risk and age at onset and demonstrate that variability at genes implicated in lysosomal function exerts the largest effect on GBA associated risk for disease. Further, these results have important implications for selection of GBA carriers for therapeutic interventions.

genetics↗