PI3K/mTOR Signaling Pathway Dual Inhibition for the Management of Neuroinflammation: Novel Insights from In Vitro Models
Alessio Ardizzone, Sarah Adriana Scuderi, Giovanna Casili, Rossella Basilotta, Emanuela Esposito, Marika Lanza
Abstract
Neuroinflammatory responses are central to the pathogenesis of neurodegenerative diseases, affecting cells of both neuronal and glial origin that respond to immune-driven inflammatory stimuli. The PI3K/mTOR signaling pathway is essential for the regulation of these neuroinflammatory processes and is therefore a promising target for therapeutic intervention. Here, we investigated the consequences of PI3K/mTOR pathway inhibition on neuroinflammation employing PF-04691502, an agent with combined PI3K and mTOR inhibitory activity. We treated SH-SY5Y, C6, BV-2, and Mo3.13 cell lines with PF-04691502 at concentrations of 0.1, 0.5, and 1 µM to assess the modulation of neuroinflammatory responses. To induce inflammation, cells were stimulated with lipopolysaccharide (LPS, 1 μg/mL) and interferon-gamma (IFN-γ, 100 U/mL). The results from the MTT assays demonstrated that PI3K/mTOR inhibition preserved cell viability at 0.5 and 1 µM across all of the cell lines, indicating its potential to mitigate inflammation-driven cytotoxicity. Subsequent ELISA assays revealed a marked decrease in the NF-κB and pro-inflammatory cytokine levels, confirming the effective suppression of inflammation through PI3K/mTOR inhibition. In addition, the SH-SY5Y cell line was exposed to MPP+ to simulate Parkinson's disease (PD)-like toxicity; then, cell viability, PD-associated markers, and apoptotic indicators were assessed. Our results indicate that inhibition of the PI3K/mTOR signaling axis may alleviate neurodegenerative processes by modulating both neuroinflammatory responses and apoptotic pathways. These findings highlight the therapeutic promise of targeting PI3K/mTOR in the context of neurodegenerative disorders and support the need for further validation through in vivo and clinical investigations.