The aim of this work is the investigation of the effect of amyloid fibrils on the physical and chemical state of the lipid bilayer of human lymphocytes membrane under the conditions of oxidative stress. Also, the process of reactive oxygen species (ROS) in human lymphocytes after amyloid fibril influence was studied. Tert-butyl hydroperoxide (t-TBH) in the final concentration 1 mM was used for oxidative stress modeling. Changes of lipid bilayer were studied using lipophilic fluorescent probes (TMA-DPH, laurdan, pyrene) which incorporated into the membrane lipid bilayer at different depths. ROS generation was measured with the help of the fluorescent probe CM-H2DCFDA. Process of lipid peroxidation (LP) in the cell membrane judged by the concentration of the malondialdehyde (MDA). Obtained results indicate that lysozyme based amyloid fibrils lead to the lipid bilayer modification which manifested as changes of fluorescent parameters of lipophilic probes incorporated into the cells membrane and process of LP. At the same time, short term exposure of amyloid fibrils does not stimulate ROS generation in the lymphocytes but intensify oxidative stress generated by t-TBH. Consequently, amyloid fibrils from lysozyme increase oxidative stress generated by t-TBH.
amyloid fibrils, lysozyme, lymphocytes, microviscosity of lipid bilayer, oxidative stress
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