Rutin attenuates negatively charged surfactant (SDS)-induced lysozyme aggregation/amyloid formation and its cytotoxicity
, 2. Mohd Shahnawaz Khan, Sheraz Ahmad Bhat, Md Tabish Rehman, Iftekhar Hassan, Shams Tabrez, Mohamed F. AlAjmi, Afzal Hussain, Fohad Mabood Husain, Salman Freeh Alamery . 2018
Amyloid fibrils are highly ordered protein assemblies known to contribute to the pathology of a variety of genetic
and aging-associated diseases. Here, we have investigated the aggregation propensity of lysozyme in the presence
of a negatively charged surfactant (SDS) and evaluated the anti-aggregation activity of rutin. Multiple approaches
such as turbidity measurements, dye binding assays, intrinsic fluorescence, circular dichroism (CD),
transmission electron microscopy (TEM), MTT and comet assays have been used for this purpose. We inferred
that SDS induces aggregation of lysozyme in 0.2–0.6 mM concentration range while at higher concentration
range (0.8–1.0 mM), it leads to solubilization/stabilization of protein. Intrinsic/extrinsic fluorescence and CD
analysis confirmed significant conformational changes in lysozyme at 0.2 mM SDS. Thioflavin T (ThT), congo
red binding and TEManalysis further reaffirmed the formation of lysozyme fibrils. Moreover,MTT assay demonstrated
cytotoxicity of these fibrils towards neuroblastoma cell lines (SH-SY5Y) and their attenuation by rutin.
Comet assay supported the cytotoxicity mechanism via DNA damage. Molecular docking results also advocate
a strong interaction between lysozyme and rutin. The current study indicates a mechanistic approach assuming
structural constraints and specific aromatic interactions of rutin with HEWL aggregates.
