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Arancibia-Carcamo, I. L.

Publications and source records attributed to Arancibia-Carcamo, I. L..

2 recordsLinked to original sources

Applying high-resolution spatial transcriptomics to characterise the amyloid plaque cell niche in Alzheimer's Disease

The amyloid plaque cell niche is a pivotal hallmark of Alzheimers disease (AD). Where early spatial transcriptomics (ST) technologies have provided valuable information on transcriptomic alterations in the small tissue domains overlaying with amyloid plaques, they lacked cellular resolution. Here we compare two novel high-resolution ST platforms, CosMx and Stereo-seq, in their ability to characterize the cellular response in the amyloid plaque niche in an AD mouse model. Combining the results from both techniques empowered us to survey the highly variable microglial-astrocytic response across the amyloid plaque micro-environment and provided a first insight into how these responses could relate to neuronal transcriptomic alterations. This pilot study demonstrates the great potential of high-resolution ST, while simultaneously highlighting limitations that, when addressed, will unleash the full power of these techniques to map the progression of molecular and cellular changes in the brains of AD patients.

neuroscience↗

Miro1-dependent Mitochondrial Dynamics in Parvalbumin Interneurons

The spatiotemporal distribution of mitochondria is crucial for precise ATP provision and calcium buffering required to support neuronal signaling. Fast-spiking GABAergic interneurons expressing parvalbumin (PV) have a high mitochondrial content reflecting their large energy utilization. The importance for correct trafficking and precise mitochondrial positioning remains poorly elucidated in inhibitory neurons. Miro1 is a Ca2+-sensing adaptor protein that links mitochondria to the trafficking apparatus, for their microtubule-dependent transport along axons and dendrites, in order to meet the metabolic and Ca2+-buffering requirements of the cell. Here, we explore the role of Miro1 in parvalbumin interneurons and how changes in mitochondrial trafficking could alter brain network activity. By employing live and fixed imaging, we found that the impairments in Miro1-directed trafficking in PV+ interneurons altered their mitochondrial distribution and axonal arborization. These changes were accompanied by an increase in the ex vivo hippocampal {gamma}-oscillation (30 - 80 Hz) frequency and promoted anxiolysis. Our findings show that precise regulation of mitochondrial dynamics in PV+ interneurons is crucial for proper neuronal signaling and network synchronization.

neuroscience↗