Study on the Aggregation of Amyloid Beta Peptide and Lysozyme in the Presence of a Short and Natural Peptide, Fasciculin-II

Protein aggregation is one of the pivotal topics in the fields of molecular life sciences with important consequences in medicine. Presence of insoluble proteinaceous deposits (protein aggregates) in human tissues is associated with the development of disorders such as amyloidosis and neurodegenerative diseases (e.g., Alzheimer’s disease (AD)). Thus finding a way to inhibit these aggregations could have a great impact in prevention and therapy of these diseases. In this study, we have examined, in the presence of fasciculin II (Fas II) (a short and highly toxic peptide in the venom of Mamba snakes), and in in vitro conditions, the aggregation of lysozyme and amyloid beta peptide (Aβ). Fas II is a potent inhibitor of acetylcholinesterase (hence it’s toxic effect) and our earlier and not published molecular dynamics results have shown that it also interacts with Aβ. We first induced the aggregation of lysozyme and Aβ in in vitro through exerting appropriate environmental conditions (low pH and high temperature for lysozyme, neutral pH and ambient temperature for Aβ, for 24 hours with mixing). We then included Fas II in our experimental mixtures to see its effects on the aggregation of lysozyme and Aβ, in separate experimental setups. We obtained our results through the use of fluorescence spectroscopy, atomic force microscopy, and electrophoresis. Our results showed that Fas II reduced aggregation of both lysozyme and Aβ, at different lengths of incubation times. These preliminary and promising results strengthen the recent approach of using short length peptides as potential candidate drugs for the treatment of AD and amyloidogenic diseases.