Research overview
The text below is the source article’s original abstract under a verified reuse license. cc by
The accumulation of aggregated alpha-Synuclein (α-Syn) in Lewy bodies and Lewy neurites is a hallmark of Parkinson's disease (PD) and Dementia with Lewy Bodies (DLB), and phosphorylation of α-Syn at Ser129 is a key pathological marker in synucleinopathies. The heterotrimeric enzyme protein phosphatase 2A (PP2A), and specifically its B55α containing isoform, which dephosphorylates phospho-S129-α-Syn, is regulated through methylation of its catalytic C subunit, a process that is controlled by the opposing activities of leucine carboxyl methyltransferase 1 (LCMT-1) and protein phosphatase methylesterase 1 (PME-1). Postmortem studies show decreased LCMT-1 and increased PME-1 levels in PD and DLB brains, leading to reduced PP2A activity and α-Syn hyperphosphorylation. To investigate the pathophysiological relevance of this regulatory axis, we employed genetically modified mice in two models of synucleinopathy, transgenic animals and intrastriatal α-Syn preformed fibrils (PFF) injections. A battery of behavioral tests was conducted to assess motor and cognitive function, followed by brain analyses quantifying phosphorylated α-Syn aggregates, neuronal toxicity, and neuroinflammatory responses, thereby evaluating how modulation of this axis influences α-Syn pathology. Overexpression of PME-1 in forebrain neurons exacerbated α-Syn pathology, characterized by increased Ser129 phosphorylation and aggregation, as well as neurodegeneration and neuroinflammation, accompanied by significant motor impairments. These effects were observed both in transgenic mice co-expressing PME-1 and human α-Syn at 9 months of age, and in PME-1 overexpressing mice six months after intrastriatal injection of α-Syn PFF. In contrast, LCMT-1 overexpression reduced α-Syn phosphorylation and aggregation, and provided robust neuroprotection, leading to improved motor outcomes in both synucleinopathy models. These findings underscore the critical role of PP2A methylation dynamics in regulating α-Syn toxicity. Accordingly, targeting the PP2A methylation machinery represents a promising therapeutic strategy to mitigate α-Syn-induced neurodegeneration and slow the progression of synucleinopathies.
Scientific assessment
Research question
Assess the question within the original study’s scope.
Methods & sample
Check the source article for study design and sample details.
Key findings
An editorially approved findings summary is not yet published for this record.
Limitations
Generalizability, bias and clinical meaning require separate assessment.
Methods, samples and clinical conclusions are not inferred from bibliographic metadata.