Biology subjects

La Vitola, P.

Publications and source records attributed to La Vitola, P..

3 recordsLinked to original sources

bioRxiv2026

Antibody treatment targeting nitrated alpha-synuclein counteracts protein spreading pathology

-Synuclein nitration is a prominent post-translational modification in Parkinsons disease, but whether nitrated -synuclein merely reflects oxidative stress or actively contributes to pathology remains unclear. Here, we generated and characterized 6G6, an antibody selective for Tyr39-nitrated -synuclein, and tested whether targeting this modified -synuclein species affected pathology in different mouse models of -synuclein aggregation and spread. In two models of -synuclein overexpression targeting medullary vagal neurons, oxidative stress was induced by either exposure to the herbicide paraquat or transgenic heterozygous expression of the Gba1-L444P mutation. Both conditions were characterized by robust -synuclein spreading that was markedly counteracted by 6G6 administration. A third model consisted of an injection of -synuclein fibrils into the striatum of -synuclein-overexpressing mice. In this model, treatment with 6G6 protected against fibril-induced aggregate pathology and ensuing degeneration of nigral dopaminergic neurons. In a pilot human study, CSF levels of Tyr39-nitrated -synuclein were measured and found increased in Parkinson patients as compared to controls. These findings identify Tyr39-nitrated -synuclein as a pathogenic, therapeutically targetable -synuclein species linking oxidative/nitrative stress to PD pathological processes.

neuroscience↗

bioRxiv2025

Metabolic reprogramming and altered ATP content impair neuroprotective functions of microglia in β-glucocerebrosidase deficiency models

Mutations in the GBA gene, which reduce {beta}-glucocerebrosidase (GCase) activity, represent the most significant genetic risk factor for Parkinsons disease (PD). Decreased GCase activity has also been observed in sporadic PD cases, supporting a broader role for GCase in the poorly understood mechanisms underlying PD etiopathogenesis. While most studies on the relationship between GBA mutations and PD have focused on neurons, evidence suggests that PD pathology promoted by GCase deficiency involves other cell types and, in particular, interactions between neuronal and glial cells. Here, we identify microglia as primary players undergoing significant alterations at early stages of the pathological processes triggered by a GCase impairment. Using both pharmacological and genetic mouse models of GCase deficiency, we observed microglial morphological, transcriptional and metabolic changes. Interestingly, these changes were associated with a cell-specific, significant reduction of microglial ATP levels. When microglial ATP depletion was reproduced in an in vitro system of co-cultured microglial and neuronal cells, the neuroprotective properties of microglia were compromised and neuronal susceptibility to oxidative stress was enhanced. These findings underscore the role of microglia in PD pathogenesis and point to a pathogenetic mechanism by which microglial metabolic disturbances leading to ATP depletion enhance neuronal vulnerability to injury and neurodegeneration. This mechanism could be targeted for therapeutic intervention aimed at mitigating PD risk and counteracting the development of PD pathology. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=112 SRC="FIGDIR/small/656111v2_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@dfd3d7org.highwire.dtl.DTLVardef@ccf2c2org.highwire.dtl.DTLVardef@155d241org.highwire.dtl.DTLVardef@15ed00a_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

bioRxiv2024

Mitochondrial oxidant stress promotes alpha-synuclein aggregation and spreading in mice with mutated glucocerebrosidase

Mutations of the glucocerebrosidase-encoding gene, GBA1, are common risk factors for Parkinsons disease. Although only a minority of mutation-carrying individuals develops the disease, the mechanisms of neuronal vulnerability predisposing to pathology conversion remain largely unclear. In this study, heterozygous expression of a common glucocerebrosidase variant, namely the L444P mutation, was found to exacerbate -synuclein aggregation and spreading in a mouse model of Parkinson-like pathology targeting neurons of the medullary vagal system. These neurons are primary sites of -synuclein lesions in Parkinsons disease and were shown here to become more vulnerable to oxidative stress after L444P expression. Nitrative burden paralleled the enhanced formation of reactive oxygen species within vagal neurons expressing mutated glucocerebrosidase, as indicated by pronounced accumulation of nitrated -synuclein. A causal relationship linked mutation-induced oxidative stress to enhanced -synuclein pathology that could indeed be rescued by neuronal overexpression of the mitochondrial antioxidant enzyme superoxide dismutase 2. Further evidence supported a key involvement of mitochondria as sources of reactive oxygen species as well as targets of oxidative and nitrative damage within L444P-expressing neurons. Scavenging of oxygen species by superoxide dismutase 2 effectively counteracted deleterious nitrative reactions and prevented nitrated -synuclein burden. Taken together, these findings support the conclusion that enhanced vulnerability to mitochondrial oxidative stress conferred by glucocerebrosidase mutations should be considered an important mechanism predisposing to Parkinsons disease pathology, particularly in brain regions targeted by -synuclein aggregation and involved in -synuclein spreading.

neuroscience↗