(755e) Effect of Polycyclic Aromatic Hydrocarbons on Alzheimer’s Disease: Insights from Molecular Dynamics Simulations

Alzheimer’s Disease is a neurodegenerative disorder, related to the development of amyloid plaques in human brain due to the aggregation of amyloid beta (Aβ) peptides. Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants, produced from human activities, such as cooking and smoking, and associated with increased risk for Alzheimer’s Disease. In-vitro studies showed an increased aggregation kinetics of Aβ₄₀ peptide in the presence of PAHs, such as phenanthrene, pyrene and benzo[a]pyrene (B[a]P). In addition, recent in-vivo experiments revealed an enhanced formation of amyloid plaques and amyloid burden percentage in the brain of animals due to the exposure to B[a]P. Furthermore, according to literature, exposure to B[a]P may lead to the decline of the neurobehavioral function in human organism. While in-vivo and in-vitro experiments show an enhanced aggregation of Aβ peptides and formation of plaques in the presence of PAHs, the molecular interactions between peptides and PAHs are obscure. In this work, we performed a molecular dynamics study via GROMACS software aimed to investigate the structure of amyloid beta peptides and their aggregation in the presence of PAHs. According to the results of the performed simulations, strong interactions between amyloid beta peptides and B[a]P molecules enhanced the aggregation kinetics of the peptides. Moreover, presence of PAHs increased amounts of beta sheets in the aggregated structures of Aβpeptides.

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