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Biology subjects

Caiazza, M.-C.

Publications and source records attributed to Caiazza, M.-C..

2 recordsLinked to original sources

Single cell spatial transcriptomic and translatomic profiling of dopaminergic neurons in health, ageing and disease

The brain is spatially organized and contains unique cell types, each performing diverse functions, and exhibiting differential susceptibility to neurodegeneration. This is exemplified in Parkinsons disease with the preferential loss of dopaminergic neurons of the substantia nigra pars compacta. Using a Parkinsons transgenic model, we conducted a single-cell spatial transcriptomic and dopaminergic neuron translatomic analysis of young and old mouse brains. Through the high resolving capacity of single-cell spatial transcriptomics, we provide a deep characterization of the expression features of dopaminergic neurons and 27 other cell types within their spatial context, identifying markers of healthy and aging cells, spanning Parkinsons-relevant pathways. We integrate gene enrichment and GWAS data to prioritize putative causative genes for disease investigation, identifying CASR as a novel regulator of dopaminergic calcium handling. These datasets (see: spatialbrain.org) represent the largest public resource for the investigation of spatial gene expression in brain cells in health, aging and disease.

molecular biology↗

Early striatal hyperexcitability in an in vitro human striatal microcircuit model carrying the Parkinson's GBA-N370S mutation

Understanding medium spiny neuron (MSN) physiology is essential to understand motor impairments in Parkinsons disease (PD) given the architecture of the basal ganglia. Here, we developed a custom three-chamber microfluidic platform and established a cortico-striato-nigral microcircuit recapitulating the striatal presynaptic triad in vitro using induced pluripotent stem cell (iPSC)-derived neurons. We found that, although cortical glutamatergic projections facilitated MSN synaptic activity, dopaminergic transmission was essential for excitability maturation of MSNs in vitro. Replacement of wild-type iPSC-dopamine neurons (iPSC-DaNs) in the striatal microcircuit with those carrying the PD-related GBA-N370S mutation induced early hyperexcitability in iPSC-MSNs through reduction of voltage-gated sodium and potassium intrinsic currents. Such deficits were resolved in aged cultures or with antagonism of protein kinase A activity in nigrostriatal iPSC-DaNs. Hence, our results highlight the unique utility of modelling striatal neurons in a modular and highly physiological circuit which is essential to reveal mechanistic insights of the loss of electrical functional integrity in the striata of GBA1 PD patients.

neuroscience↗