Isoferulic acid

Parkinson’s disease (PD), the second most common neurodegenerative disorder globally, arises from selective dopaminergic neuron degeneration. While current therapies address symptoms, disease-modifying agents remain an unmet need. Herein, we investigated Nicotiana tabacum L. (Solanaceae), a plant linked epidemiologically to reduced PD risk, as a source of multi-target neuroprotective compounds. From ultra-low nicotine (< 0.04%) tobacco leaves, we isolated 22 molecules, including a novel 21-norsesterterpenoid (Nicotiazanorpenoid A) and eight previously unreported compounds. Systematic evaluation revealed three synergistic neuroprotective mechanisms: (1) Antioxidant activity: Scopoletin (3) and isoferulic acid (6) showed significant radical scavenging capacity (ABTS assay; IC50 = 27.74, and 18.13 μM, respectively); (2) Neuronal protection: cis-11,14,17-Eicosatrienoic acid methyl ester (14) enhanced survival (93.94% vs. control) in 6-OHDA-induced PC12 cells, surpassing rasagiline (88.36% at equivalent concentrations); (3) MAO-B inhibition: five compounds displayed selective inhibition, with scopoletin (3) exhibiting highest potency (Ki = 20.7 μM). Notably, plant prostaglandins (10/11) were identified as competitive MAO-B inhibitors first time through molecular docking and 100-ns MD simulations, revealing stable binding at the FAD site (ΔG = − 10.42, and − 9.75 kcal/mol, respectively).Graphical Abstract