Silymarin stimulates DNA repair in UV-exposed NHEK.

<p><b>(A),</b> NHEK were treated with silymarin for 3 h before UVB (150 J/m²) irradiation. Cells were harvested 36 h later, cytospun, and subjected to cytostaining to detect CPD⁺ cells, as detailed in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0021410#s2" target="_blank">Materials and methods</a>. CPD-positive cells are dark brown. Magnification, x400. Photomicrographs are representative of three independent experiments. CPD+ cells were not detectable in non-UVB-exposed keratinocytes. <b>(B)</b> The analysis of damaged DNA in the form of CPDs was performed by dot-blot analysis using antibody specific to CPDs or thymine dimers. Genomic DNA from various treatment groups was subjected to dot-blot analysis using an antibody specific to CPDs. Results are shown from a single experiment and is representative of 3 independent experiments.