In silico Evaluation of Potential Peptide Inhibitors from the Odontomachus chelifer Venom Gland Transcriptome Against Alzheimer’s Disease Targets

Ant venoms represent a rich yet underexplored reservoir of bioactive peptides with pleiotropic pharmacological potential. Given the multifactorial pathogenesis of Alzheimer’s disease (AD), focusing on the amyloidogenic and cholinergic pathways, discovering multi-target-directed ligands from animal toxins is a promising therapeutic strategy.

This study aimed to evaluate, through an in silico approach, the therapeutic potential and safety profile of three synthetic peptides (P1, P2, and P3) derived from the venom gland transcriptome of the neotropical trap-jaw ant Odontomachus chelifer against key molecular targets of AD.

Physicochemical properties, bioactivity, and toxicity values were predicted using ProtParam, PeptideRanker, and ToxinPred softwares. Three-dimensional structures were modeled via PEP-FOLD 3 and stereochemically validated using Ramachandran plots and MolProbity scores. Molecular docking was performed on HADDOCK 2.4 against Aβ monomer (PDB: 6SZF), Aβ fibril (PDB: 2MXU), β-secretase 1 (PDB: 3TPJ), and acetylcholinesterase (PDB: 3LII), followed by Gibbs free energy (ΔG) prediction via PRODIGY. Finally, in vitro cytotoxicity was assessed by the AlamarBlue assay in normal human astrocytes (NHA) and human neuroblastoma (SH-SY5Y) cell lines at 1, 10, and 100 μM.

All peptides exhibited low molecular mass, cationic profiles, α-helical conformations with 100% favored Ramachandran angles, and non-toxic predictions. In molecular docking, P3 stood out as the most promising multi-target candidate, displaying the highest binding affinity predicted across targets, notably outperforming curcumin, a known Aβ anti-aggregant, against the Aβ monomer (ΔG=-6.9) by interacting with the hydrophobic aggregation core and C-terminal residues. P2 demonstrated strategic binding to the BACE1 catalytic dyad (Asp32) and flap region, while all peptides bound to the peripheral anionic site of AChE. In vitro assays confirmed the absence of neurotoxicity in both NHA and SH-SY5Y cells across all tested concentrations; remarkably, P1 and P3 at 100 μM significantly increased astrocyte viability.

The synthetic peptides derived from O. chelifer venom, particularly P3 and P2, demonstrated favorable safety profiles and strategic in silico interactions with amyloidogenic and cholinergic targets, positioning them as promising lead compounds for multi-target drug design against AD.