Synthesis of keratine, silver, and flavonols nanocomposites to inhibit oxidative stress in pancreatic beta-cell (INS-1) and reduce intracellular reactive oxygen species production

Abstract

Flavonols (FLA) fromVaccinium macrocarpon (V. macrocarpon) were identified using high-performance liquid chromatography coupled with mass spectrometry detection. Nanoparticles were prepared using highly crosslinked keratin (KER) from human hair andsilver and entrapped with flavonols [KER + FLA + AgNPs].Nanocomposites were characterized using UV–Vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction,zeta potential, and dynamic light scattering, andrelease profiles.The interactions between the capping agent and the silver core have been investigated using FTIR spectroscopy·H2O2 is a source of Reactive Oxygen Species (ROS) and acts as an activator of oxidative stress affecting NS-1 cells, and the protective effect of the nanocomposites were evaluated against H2O2-induced pancreatic β-cell damage.LC-MS/MS and HPLC analyses revealed the presence of 12 flavonols inV. macrocarponplant extract.The cell apoptosis and proliferation, were evaluated by Hoechst 33342 staining, flow cytometry and Cell Counting Kit-8 respectively. Preincubation of the NS-1 cells with 250 µg/mL of H2O2induced oxidative stress conditions that showpancreatic β-cell dysfunction, includingROS, cell death, mitochondrial function, antioxidant enzymes, and lipid peroxidation. Nevertheless, pretreatment with FLA and [KER + FLA + AgNPs] prevented mitochondria disruption, maintained cellular ATP levels, inhibited LDH release, intracellular ROS production, decreased lipid peroxidation, increased expression of antioxidant enzymes (CAT, SOD, and GPx) and GSH levels. These results indicate that nanocomposites couldprotect rat INS-1 pancreaticβ-cell from H2O2-induced oxidative damage, apoptosis and proliferation by reducing the production of intracellular reactive oxygen species.