Effects of Turkish propolis on expression of hOGG-1 and NEIL-1.

BACKGROUND/AIM Propolis is a bee product with antioxidative, antimutagenic, and other beneficial properties, and it is used as a natural drug. It is rich in polyphenolic compounds. Its composition varies depending on the particular geographical region. Oxidative stress is caused by an imbalanced free radical production and antioxidant system. The effects of flavonoids on the expression of DNA repair enzymes have been examined previously; however, no study has investigated the effects of propolis. This study investigated the effects of ethanolic extracts of Turkish propolis (EEP) on the expression of DNA repair enzymes. MATERIALS AND METHODS The effects of EEP and tertiary-butyl-hydroperoxide (t-BHP) on cell viability were determined using MTT DNA damage was determined using comet assay. mRNA expression of target enzymes was detected using RT-PCR. RESULTS According to the cytotoxicity analysis, after a recovery time of 4 h, appropriate damage agent t-BHP and optimum EEP concentrations were 300 µM and 200 µg/mL, respectively. 8-Oxoguanine-glycosylase (hOGG-1) and endonuclease-VIII-like-1 (NEIL-1) expressions increased in the positive control group (t-BHP alone) and the study group (t-BHP+EEP). Maximum increase in NEIL-I expression was at hour 12 in the positive control group and at hour 8 in the study group. CONCLUSION EEP can be considered as a potential source of functional food and pharmaceutical agents.