Abstract: Amyloid aggregation of polypeptides is related to a
growing number of pathologic states known as amyloid disorders. In
recent years, blocking or reversing amyloid aggregation via the use of
small compounds are considered as two useful approaches in
hampering the development of these diseases. In this research, we
have compared the ability of several manganese-salen derivatives, as
synthetic compounds, and apigenin, as a natural flavonoid, to inhibit
of hen egg-white lysozyme (HEWL) aggregation, as an in vitro
model system.
Different spectroscopic analyses such as Thioflavin T (ThT) and
Anilinonaphthalene-8-sulfonic acid (ANS) fluorescence, Congo red
(CR) absorbance along with transmission electron microscopy were
used in this work to monitor the HEWL aggregation kinetic and
inhibition. Our results demonstrated that both type of compounds
were capable to prevent the formation of lysozyme amyloid
aggregation in vitro. In addition, our data indicated that synthetic
compounds had higher activity to inhibit of the β-sheet structures
relative to natural compound. Regarding the higher antioxidant
activities of the salen derivatives, it can be concluded that in addition
to aromatic rings of each of the compounds, the potent antioxidant
properties of salen derivatives contributes to lower lysozyme fibril
accumulation.