Inhibitory Effects of Gliadin Hydrolysates on BACE1 Expression and APP Processing to Prevent Aβ Aggregation

Area of Science:

• Neuroscience
• Biochemistry
• Food Science

Background:

• Alzheimer's disease (AD) is linked to amyloid-beta (Aβ) accumulation.
• Beta-secretase 1 (BACE1) enzyme activity is crucial for Aβ production and a therapeutic target for AD.
• The BACE1 inhibitory potential of food protein hydrolysates is largely unexplored.

Purpose of the Study:

• To evaluate the BACE1 inhibitory potential of protein hydrolysates from gliadin, whey, and casein.
• To identify specific hydrolysates that can attenuate Aβ production and aggregation.
• To explore the potential of these hydrolysates as natural therapeutic agents for AD.

Main Methods:

• Preparation of protein hydrolysates using bromelain, papain, and thermolysin.
• In vitro and cellular assays to assess BACE1 inhibition.
• Analysis of BACE1 expression and amyloid precursor protein (APP) processing in N2a/PS/APP cell cultures.

Main Results:

• Bromelain-hydrolyzed gliadin (G-Bro) demonstrated the most potent BACE1 inhibition (IC50 = 0.408 mg/mL).
• G-Bro significantly reduced BACE1 expression and APP processing in cellular assays.
• The peptide composition of G-Bro, including proline, lysine, hydrophobic, and glutamine residues, likely contributes to its inhibitory activity.

Conclusions:

• Gliadin hydrolysates, particularly G-Bro, are effective natural inhibitors of BACE1.
• G-Bro shows potential for attenuating Aβ aggregation, suggesting applications in AD prevention dietary interventions.
• Further research is needed to elucidate specific peptide interactions and their bioactivity in neural pathways for AD therapeutics.