NÖRONAL HÜCRELERDE HİDROJEN PEROKSİT HASARINA KARŞI EPİGALLOKATEŞİN GALLAT VE RESVERATROLÜN KORUYUCU ETKİLERİNİN ARAŞTIRILMASI
Project no. 21274 · Status: Kapanmış · 2020
Summary
Investigation of the Protective Effects of Epigallocatechin Gallate and Resveratrol Against Hydrogen Peroxide Damage in Neuronal Cells Neurodegeneration is the progressive loss of neuronal cells and deterioration of their structural integrity. The incidence of neurodegenerative diseases is increasing day by day. Genetic factors, environmental factors and oxidative stress play a role in the emergence of neurodegenerative diseases due to damage to neurons. The use of various phenols found in nature to delay or prevent neurodegeneration is on the agenda. Superoxide radicals can form at various points of the electron transport systems in our body. Hydrogen peroxide is formed mainly by dismutation of the superoxide radical. The superoxide radical takes two protons via the superoxide dismutase enzyme to form hydrogen peroxide. In conditions such as ischemia, trauma, hemorrhage and radioactivity, aerobic phosphorylation in mitochondria changes and accordingly, oxygen leakage from the electron transport system increases. During normal metabolism in our body or through various external factors, free radicals such as hydrogen peroxide increase and cause various diseases such as cancer and cardiovascular diseases. These harmful species are kept under control by the body's endogenous antioxidant systems. Supporting antioxidant systems with dietary antioxidant components is of great importance in the prevention of diseases related to oxidant particles. Epigallocatechin-3-gallate in green tea and resveratrol in grapes are powerful antioxidant compounds. Epigallocatechin-3-gallate (EGCG); It acts as an anticarcinogen through various pathways by affecting DNA hypermethylation, telomerase activity, angiogenesis, metastasis, tumor cell apoptosis, tumor suppressor genes and oncogenes. In addition to being an anticarcinogen and a powerful antioxidant, EGCG has anti-inflammatory, antifibrotic and osteogenic effects. Resveratrol basically has antioxidant effect; It provides the amount of reactive oxygen produced by NAPH oxidase, mitochondrial superoxide formation, superoxide formation from nitric oxide synthase, reducing oxidase activity and expression. In addition to the anticarcinogenic pathways of EGCG, resveratrol also affects various cancer stages from onset to progression by affecting various signal-transduction pathways that control cell growth and division, inflammation, apoptosis, metastasis, and angiogenesis. This study was conducted to investigate and compare the protective effects of epigallocatechin-3-gallate and resveratrol antioxidant agents against hydrogen peroxide damage in SH-SY5Y neuronal cells. For this purpose, as a result of literature review, first the effective dose and incubation period of hydrogen peroxide were determined, this dose was determined as 250 µM and this dose was used in toxic groups. In SH-SY5Y cells, hydrogen peroxide toxicity was administered to three treatment groups, including epigallocatechin-3-gallate, resveratrol, epigallocatechin-3-gallate and resveratrol, after 2 and 24 hours of pretreatment. Cell survival was evaluated with MTS test in these groups. The clonogenic test was applied to observe the colony forming abilities of the cells and the results were evaluated with the post-hoc Turkey HSD test. As a result of both evaluations, it was observed that epigallocatechin-3-gallate and resveratrol were more protective at low doses and increased the colony forming ability. Another step of this study was to investigate the formation of apoptosis over the level of caspase-3 in cells with the ELISA test. As a result of ELISA test, it was observed that epigallocatechin-3-gallate and resveratrol decreased active caspase-3 levels. According to the results obtained, it was determined that the antioxidant agents epigallocatechin-3-gallate and resveratrol played a protective role against hydrogen peroxide, an oxidant agent, by increasing cell survival and colony forming ability, and decreased apoptosis