The antimutagenic/desmutagenic activity of a leonardite humic acid (LHA) and a soil humic acid (SHA) was studied in the cultured human lymphoblastoid cell line TK6 treated with mitomycin C (MMC) as reference mutagen by evaluating the induction of micronuclei (MN). Two different concentrations of HA were used, 2.5 and 10 µg/ml, in three different treatments: (1) HA alone (genotoxic test); (2) HA after 2-h pre-incubation with 0.3 µM of MMC (desmutagenic test) and (3) combinations of HA and MMC at 0.3 µM without pre-incubation (antimutagenic test). Neither of the HA used alone did produce genotoxic effects, but both HAs reduced significantly the frequencies of MN induced by MMC, especially in the desmutagenic test. A slight cellprotective effect against the cytoxicity of MMC was also exhibited by the two HAs in the desmutagenic test. The LHA showed a desmutagenic/antimutagenic activity that was more pronounced than that of SHA, which is possibly related to the higher carboxylic group content and lower phenolic group content of LHA. These results confirm the antigenotoxic action exerted by HAs in human cells, similarly to what has been previously observed in various plant species.
Humic acids reduce the genotoxicity of mitomycin C in human lynphoblastoid cell line TK6
FERRARA, GIUSEPPE;LOFFREDO, Elisabetta;SENESI, Nicola;
2006-01-01
Abstract
The antimutagenic/desmutagenic activity of a leonardite humic acid (LHA) and a soil humic acid (SHA) was studied in the cultured human lymphoblastoid cell line TK6 treated with mitomycin C (MMC) as reference mutagen by evaluating the induction of micronuclei (MN). Two different concentrations of HA were used, 2.5 and 10 µg/ml, in three different treatments: (1) HA alone (genotoxic test); (2) HA after 2-h pre-incubation with 0.3 µM of MMC (desmutagenic test) and (3) combinations of HA and MMC at 0.3 µM without pre-incubation (antimutagenic test). Neither of the HA used alone did produce genotoxic effects, but both HAs reduced significantly the frequencies of MN induced by MMC, especially in the desmutagenic test. A slight cellprotective effect against the cytoxicity of MMC was also exhibited by the two HAs in the desmutagenic test. The LHA showed a desmutagenic/antimutagenic activity that was more pronounced than that of SHA, which is possibly related to the higher carboxylic group content and lower phenolic group content of LHA. These results confirm the antigenotoxic action exerted by HAs in human cells, similarly to what has been previously observed in various plant species.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
