Evaluation of antigenotoxicity effects of umbelliprenin on human peripheral lymphocytes exposed to oxidative stress

The protective properties of a prenylated coumarin, umbelliprenin (UMB), on the human lymphocytes DNA lesions were tested. Lymphocytes were isolated from blood samples taken from healthy volunteers. DNA breaks and resistance to H2O2-induced damage were measured using a single-cell microgel electrophoresis technique under alkaline conditions (comet assay). Human lymphocytes were incubated in UMB (10, 25, 50, 100, 200, and 400 mu M) alone or a combination of different concentrations of UMB (10, 25, 50, 100, 200, and 400 mu M) and 25 mu M H2O2. Untreated cells, ascorbic acid (AA; 25, 50, 100, 200, and 400 mu M) and H2O2 (25 mu M) were considered as negative control, positive control, and the standard antioxidant agent for our study, respectively. Single cells were analyzed with TriTek Cometscore version 1.5 software. The DNA damage was expressed as percent tail DNA. UMB exhibited a concentration-dependent increase in protection activity against DNA damage induced by 25 mu M H2O2 (from 67.28% to 39.17%). The antigenotoxic activity of AA, in the range 0-50 mu M, was greater than that of UMB. However, no significant difference (p > 0.05) in the protective activity was found between UMB and AA at concentrations of approximately higher than 50 mu M.