Protective effect of Geranium thunbergii against H2O2-induced oxidative stress on NCTC-1469 cells

Free radical stress leads to diseases such as arthritis, atherosclerosis, diabetes mellitus, neurodegenerative disease and carcinogenesis [1]. Several studies are ongoing worldwide to find natural antioxidants from plant [2,3]. We assessed the antioxidant activities of Geranium thunbergii ethanol extract (TKM2079-E) in H₂O₂-treated NCTC-1469 cells and free radical scavenging activities. H₂O₂-induced cytotoxicity was significantly attenuated by TKM-2079-E via enhancing cell viability. Intracellular ROS levels induced by H₂O₂ were also significantly reduced by TKM2079-E. Additionally, total phenolic and flavonoid contents of TKM2079-E were 169.4 mg/g and 48.3 mg/g respectively. TKM2079-E was also possessed free radical scavenging activities such as DPPH (IC₅₀= 23.4 µg/mL), superoxide anion radical (IC₅₀= 80.9 µg/mL) and ABTS+ (IC₅₀= 46.3 µg/mL). These results suggested that the TIM2079-E is a source of natural antioxidants which might be helpful in preventing the progress of various oxidative stress mediated diseases including aging.

Fig. 1: Effect of TKM2079-E on hydrogen dioxide (H₂O₂)-mediated ROS induction in NCTC-1469 cells. NCTC-1469 was pre-treated with DCFH-DA for 30 min, followed by the indicated concentration of TKM2079-E and 1 mM of H₂O₂ treatment for 3h incubation. Levels of intracellular ROS were measured by flow cytometry. (A) Unstaining, (B) Control, (C) H₂O₂-treated cells, TKM2079-E (D) 62.5 µg/ml and H₂O₂-treated cells (E) 125 µg/ml and H₂O₂-treated cells (F) 250 µg/ml and H₂O₂-treated cells.

Acknowledgements: This work was supported by Ministry of Health & Welfare “The Traditional Korean Medicine Industry Development Product R&D Program (C100001)”.

Keywords: Antioxidant, Free radical scavenging activity, ROS.

References:

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