Fig. 2.

DDR protein and nuclear p53 levels in H. pylori–infected cells treated with or without KRG. (A) Various culture periods were used to determine DDR protein levels (p-ATM, ATM, p-Chk2, Chk2, Mdm2, ARF, p-p53, and p53). (B) Indicated concentration of KRG was treated to the cells 2 h before H. pylori stimulation. 6 h-culture was used to determine DDR protein levels. (C) For determination of nuclear p53 level, 1 μg/mL of KRG was treated to the cells 2 h before H. pylori infection and the cells were cultured for 6 h. Images show immunofluorescence staining for p53 (red) and DNA counterstaining with DAPI (blue). Nuclear p53 (shown by brackets) was found in small areas in uninfected (none) group and KRG-treated and H. pylori–infected group (H. pylori + KRG), while nuclear p53 was found in relatively large areas in untreated, H. pylori–infected group (H. pylori alone). (D) Fluorescence images expressed the ratio of the fluorescence densities of p53 and the nuclei stain DAPI. Values are mean ± SEM. *p < 0.05 vs. untreated, uninfected group (none) and ⁺p < 0.05 vs. untreated, H. pylori–infected group (H. pylori alone).

ARF, alternative reading frame; ATM, ataxia-telangiectasia-mutated; Chk2, checkpoint kinase 2; DAPI, 4ʹ,6-diamidino-2-phenylindole; DDR, DNA damage response; KRG, Korean Red Ginseng extract; Mdm2, mouse double minute 2; SEM, standard error of the mean.