Human SNCA Stable Cell Line - SH-SY5Y

Alpha-synuclein (α-syn, also known as SNCA) overexpression models are widely used to elucidate the molecular mechanisms of Parkinson's disease (PD), particularly given the dose-dependent transition of the protein between physiological function and toxicity. Here, researchers generated and characterized a series of neuronal cell lines stably expressing GFP-tagged wild-type (WT) or A53T mutant α-syn across two human cell models-SH-SY5Y neuroblastoma cells and ReNcell VM neural progenitor cells-at both low and high overexpression levels. Using this experimental system, the researchers demonstrated that the A53T mutant consistently induced cytotoxicity, oxidative stress, and mitochondrial dysfunction in both cell types. In contrast, WT α-syn elicited markedly different effects depending on the cellular context: it enhanced mitochondrial function and cell viability in SH-SY5Y cells, whereas the same protein caused mitochondrial damage and exacerbated oxidative stress in ReNcell VM cells. These contrasting metabolic responses were reflected by increased respiratory activity in SH-SY5Y cells and a significant decline in respiratory activity in ReNcell VM cells overexpressing WT α-syn. Notably, the post-translational modification (PTM) profiles of overexpressed WT α-syn differed significantly between the cell types; ReNcell VM cells exhibited more pronounced modification characteristics even in the absence of overt protein aggregation. This finding highlights cell-type-specific PTM profiles, which may be linked to the differential susceptibility of cells to pathological injury.

Here, researchers investigated potential mitochondrial alterations induced by α-synuclein (α-syn) overexpression using quantitative flow cytometry analysis involving TOM20 staining and MitoTracker dye (Figure 1). Compared to control cells, α-syn overexpressing SH-SY5Y cells exhibited altered TOM20 staining patterns, particularly within the high-expression population. Representative images revealed a more compact and punctate mitochondrial morphology (Figure 1A). Quantitative analysis further supported these findings: an increase in MitoTracker signal intensity reflected an increase in mitochondrial density (Figure 1C). In ReNcell VM cells, no morphological differences were observed between wild-type (WT) α-syn overexpressing cells and controls; however, quantitative analysis showed increased MitoTracker fluorescence intensity in the high-expression group compared to controls (Figure 1D). ReNcell VM cells overexpressing the A53T mutant α-syn exhibited mitochondrial structural alterations similar to those seen in the SH-SY5Y cell line, specifically a shift toward fragmented and granular mitochondrial morphologies (Figure 1B). High levels of A53T expression resulted in extensive mitochondrial clustering and a loss of filamentous structures. A significant increase in mitochondrial signal density-particularly in the A53T high-expression group-quantitatively confirmed these morphological changes (Figure 1D).

Figure 1. α-syn overexpression alters mitochondrial integrity in a variant-, dose- and cell-type dependent manner in neuronal cell models. (Momand M U D, et al., 2026)