miR-200a Modulates the Expression of the DNA Repair Protein OGG1 Playing a Role in Aging of Primary Human Keratinocytes

Figure 1

Oxidative damage in aged primary human keratinocytes. (a) Intracellular ROS steady-state levels were determined incubating keratinocytes from young and old donors (at 2nd passage) with 2,7-dichlorofluorescein diacetate (H2 DCFDA) and detected by flow cytometry. ROS level was given by fluorescence intensity per 10³ cells. Data were shown as fold change (, by Student’s test). (b) DNA was isolated from young and old donors (at 2nd passage), and the 8-OH-dG residue amount was determined by HPLC-ED. 2-Deoxyguanosine (dG) was measured in the same run of corresponding 8-OH-dG, and the results were expressed as the number of 8-OH-dG residues/10⁶dG residues. Data were shown as fold change (, by Student’s test). (c–f) The best-fit line determined by linear regression was shown for each data series, with R² coefficient and Spearman correlation coefficient (Rs). Two-tailed value was reported in Result. Densitometric value of p16 expression was referred to Western blots shown in [35].

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