INFLAMMATORY STRESS SIGNALING ASSOCIATED WITH Α-SYNUCLEIN BURDEN IN CELLULAR MODELS OF PARKINSON’S DISEASE

α-synuclein (α-syn) misfolding and aggregation are central drivers of Parkinson’s disease (PD) pathology, with aging being the strongest risk factor; yet the mechanisms connecting aging to α-syn–driven pathology remain elusive. Age-associated inflammatory signaling, particularly within the central nervous system, has emerged as a potential contributor to neurodegeneration, but its relationship to neuronal α-syn pathology remains poorly understood. In this study, we generated and systematically characterized novel neuronal α-syn models with stable, dosage-dependent overexpression of wild-type (WT) or A53T mutant α-syn in two cellular backgrounds: SH-SY5Y neuroblastoma cells and ReNcell VM neural progenitor cells. These models enabled controlled assessment of how α-syn overexpression level, mutation status, and cellular context influence protein processing, mitochondrial function, redox balance, and stress signaling pathways relevant to neurodegeneration.

Phenotypic analyses revealed cell-type-specific responses. WT α-syn overexpression elicited divergent, cell-type–dependent responses in metabolic activity, mitochondrial respiration, and oxidative stress. Across both backgrounds, A53T α-syn exacerbated stress phenotypes, while post-translational modification analyses highlighted context-dependent regulation of α-syn. Moreover, we assessed changes in inflammatory signaling by measuring various components of the senescence-associated secretory phenotype (SASP), including IL-2, IL-6, and IFN-α, and MMP3 in both cellular lysates and conditioned media to evaluate α-syn overload–associated inflammatory responses

By linking α-syn burden to neuronal inflammatory and senescence-associated signaling, this study provides insight into how intrinsic neuronal stress may shape immune-related pathways in PD. These findings directly contribute to the current efforts aimed at understanding the contribution of neuroimmune interactions to PD pathogenesis.