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Catenaccio, A.

Publications and source records attributed to Catenaccio, A..

2 recordsLinked to original sources
bioRxiv2023

Applying the area fraction fractionator (AFF) probe for total volume estimations of somatic, dendritic and axonal domains of the nigrostriatal dopaminergic system in a murine model

Using the nigrostriatal dopaminergic system as a case example, we describe a protocol based on Cavalieris principle to estimate the total volume of its somatic, nuclear, dendritic and axonal domains in the adult mouse. This protocol requires serial section analysis, a confocal laser scanning microscope (CLSM), and a stereological software combining the serial section manager (SSM) tool and the area fraction fractionator (AFF) probe. The protocol consists of the following steps: 1) systematic random sampling (SRS) of sites across sections for relevant regions of interest (ROI), which in this study included the substantia nigra pars compacta (SNc) and pars reticulata (SNr), the nigrostriatal tract, and the caudate-putamen complex (CP), 2) high resolution image acquisition of all SRS sites within and across sections, 3) loading of images on the previously defined SRS sites, 4) marking of all cellular structures of interest (cSOI) in the images, including perikarya and cell nuclei, dendrites, axonal segments and varicosities, using Cavalieris point-counting grids, and 5) estimation of cSOI total volume using the estimated area of each cSOI in every brain section, and the distance between sections. The added volume for all cSOI comprising the nigrostriatal dopaminergic system, in this murine model is around 0.37 mm3, with approximately 5% corresponding to perikarya and cell nuclei, 10% to neuropil/dendrites in substantia nigra, and 85% to axonal segments and varicosities within the CP. The use of a simple quantitative approach to assess the global state of a system may allow quantification of compartment-specific changes that may accompany neurodegenerative processes.

neuroscience↗
bioRxiv2019

The necroptosis machinery mediates axonal degeneration in a model of Parkinson disease

Parkinsons disease (PD) is the second most common neurodegenerative condition, characterized by motor impairment due to the progressive degeneration of dopaminergic neurons in the substantia nigra and depletion of dopamine release in the striatum. Accumulating evidence suggest that degeneration of axons is an early event in the disease, involving destruction programs that are independent of the survival of the cell soma. Necroptosis, a programmed cell death process, is emerging as a mediator of neuronal loss in models of neurodegenerative diseases. Here, we demonstrate activation of necroptosis in postmortem brain tissue from PD patients and in a toxin-based mouse model of the disease. Inhibition of key components of the necroptotic pathway resulted in a significant delay of 6-hydroxydopamine dependent axonal degeneration of dopaminergic and cortical neurons in vitro. Genetic ablation of necroptosis mediators MLKL and RIPK3, as well as pharmacological inhibition of RIPK1 in vivo, decreased dopaminergic neuron degeneration, improving motor performance. Together, these findings suggest that axonal degeneration in PD is mediated by the necroptosis machinery, a process here referred to as necroaxoptosis, a druggable pathway to target dopaminergic neuronal loss.

neuroscience↗