Puerarin inhibits DNA damage of HaCaT cells induced by UVB via ceramide pathway

This study is to investigate the effect and mechanism of puerarin on DNA damage of HaCaT cells induced by UVB.  Puerarin pre-treated cells were irradiated with UVB at 30 mJ·cm⁻².  Twenty four hours after irradiation, DNA damage was detected by comet assay, ceramide was measured by thin layer chromatography and gas chromatography, intracellular free calcium ion was analyzed by flow cytometry, the phosphorylation level of p38 protein was examined by Western blotting method.  Levels of DNA damage, ceramide, free calcium ion and p-p38 protein were elevated in UVB model cells.  Contrary to the model group, all indicators above were reduced in all groups pre-treated by puerarin.  Puerarin restrains the ceramide accumulation to block downstream p38 MAPK pathway and calcium ion rising, therefore reduces DNA damage in HaCaT cells induced by UVB.