Identificationof Chlorogenic Acids from Moringa oleifera Leaves as Modulators of Prion AggregationUsing Affinity Selection-Mass Spectrometry

Prion diseases are fatal neurodegenerative disorders caused by the misfolding and aggregation of the cellular prion protein (PrP^C) into its pathogenic form (PrP^Sc), leading to progressive neurodegeneration. Currently, no effective treatments are available, highlighting the need for novel therapeutic strategies. In this study, we explored the potential of Moringa oleifera extracts as a source of bioactive compounds that could modulate prion protein aggregation. A hydroethanolic extract from M. oleifera leaves was analyzed using PrP aggregation inhibition profiling via real-time quaking-induced conversion (RT-QuIC) assays, in combination with affinity selection-mass spectrometry (AS-MS). This approach identified chlorogenic and neochlorogenic acids as potent inhibitors of prion aggregation. These compounds exhibited significant antiprion activity, with IC₅₀ values of 64.41 ± 12.12 and 35.34 ± 7.09 μM, respectively. In addition to inhibiting the conversion of PrP^C to PrP^Sc, both compounds could disaggregate preformed PrP^Sc fibrils <i>in vitro</i>. AS-MS proved to be a valuable tool for isolating the modulators of PrP aggregation directly from crude natural product extracts, avoiding the need for expensive and time-consuming fractionation and purification processes. Identifying chlorogenic and neochlorogenic acids highlights the therapeutic potential of natural products in combating prion diseases and other amyloidogenic disorders. Our findings suggest that these bioactive compounds could serve as promising lead compounds for developing novel treatments for prion diseases. Further <i>in vivo</i> studies and pharmacokinetic optimization are warranted to explore their full therapeutic potential.