Neuroprotective Mechanisms of Porcine Brain Enzyme Hydrolysate in Memory Impairment: Multi-Target Strategy Against Amyloid-β-Induced Neurotoxicity

This study investigated the potential neuroprotective mechanisms of porcine brain enzyme hydrolysate (PBEH) against Alzheimer's disease pathology using differentiated SH-SY5Y cells. Differentiated neuronal cells were treated with 40 μM amyloid-β(1-42; Aβ) to induce neurotoxicity, followed by PBEH treatment (12.5-400 μg/mL), Com-A (peptide-based neuroprotective supplement; 200 μg/mL) treatment, and Com-B (herbal extract known for improving memory function; 100 μg/mL) treatment. Key assessments included cell viability, Aβ aggregation in adding 10 μM Aβ, amyloidogenic proteins (APP, BACE), synaptic markers (BDNF, ERK), apoptotic markers (BAX/BCL-2, caspase-3), oxidative stress (reactive oxygen species (ROS)), cholinergic function (ChAT, AChE), MAPK signaling (JNK, p38), and neuroinflammation (IL-1β). PBEH contained high concentrations of amino acids, including L-lysine (32.3 mg/g), L-leucine (42.4 mg/g), L-phenylalanine (30.0 mg/g) and the PSIS peptide (86.9 μg/g). Treatment up to 400 μg/mL showed no cytotoxicity and had cognitive protection effects up to 152% under Aβ stress (<i>p</i> < 0.05). PBEH significantly attenuated Aβ aggregation, decreased APP (28%) and BACE (51%) expression, enhanced synaptic function through increased BDNF, and restored ERK phosphorylation (<i>p</i> < 0.05). Anti-apoptotic effects included a 76% reduction in the BAX/BCL-2 ratio, a 47% decrease in caspase-3, and a 56% reduction in ROS levels. Cholinergic function showed restoration via increased ChAT activity (<i>p</i> < 0.01) and decreased AChE activity (<i>p</i> < 0.05). PBEH reduced IL-1β levels by 70% and suppressed JNK/p38 phosphorylation (<i>p</i> < 0.05). While Com-A enhanced BDNF and Com-B showed anti-inflammatory effects, PBEH demonstrated activity across multiple pathway markers. In conclusion, these findings suggest that PBEH may enable neuronal preservation through multi-pathway modulation, establishing foundational evidence for further mechanistic investigation in cognitive enhancement applications.