Erinacine C Attenuates Alzheimer's-like Pathology: A Study in APP/PS1 Mice and PC12 Cells

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by amyloid-beta (Aβ) deposition and cognitive decline. Clinical evidence indicates that Hericium erinaceus whole fruiting body powder offers limited therapeutic efficacy, which is suggested to be constrained by whole-food matrix interference and uncertainties in central nervous system (CNS) exposure. Therefore, we hypothesized that erinacine C (EC)-a purified active component from Hericium erinaceus mycelia-could resolve these limitations and potentially exhibit favorable neuroprotective effects owing to its low molecular weight and lipophilicity. In this study, we investigated the neuroprotective potential and associated signaling alterations of EC using APP/PS1 transgenic mice and Aβ_25-35-induced PC12 cells. In vivo, oral administration of EC alleviated deficits in activities of daily living, as evidenced by improvements in nesting and burrowing behaviors, along with enhanced short-term spatial memory in the Y-maze test. EC treatment was associated with a reduction in hippocampal Aβ plaque accumulation, suppression of glial activation (GFAP and IBA1), and decreased IL-6 levels in both serum and hippocampal tissues. In vitro, EC intervention counteracted Aβ_25-35-induced cytotoxicity in PC12 cells. Analysis of signaling markers revealed that EC treatment was accompanied by a restoration of p-Akt/Akt levels and a suppression of p-GSK3β (Tyr216) activation. Consequently, EC treatment was correlated with reduced tau hyperphosphorylation, the up-regulation of the anti-apoptotic protein Bcl-2, and the down-regulation of pro-apoptotic markers including Bax and cleaved-caspase-3, thereby lowering the total apoptotic rate. Taken together, these findings suggest that EC may mitigate cognitive impairment and neurodegeneration in parallel with alterations in the Akt/GSK3β/tau/caspase-3 signaling response, thereby representing a potentially promising therapeutic candidate for the intervention of AD.