Chlorophyllin is both a positive and negative modifier of mutagenicity.

摘要: The mechanism responsible for the modification of mutagenicity by chlorophyllin has been investigated using mutagenic compounds with different mechanisms action, including monofunctional alkylating agents, N-methyl-N'-nitrosourea (MNU) and ethylmethanesulphonate (EMS); nitrosamines related to tobacco products, i.e. dimethyl-nitrosamine (DMN), N-nitrosonornicotine (NNN) 4-(N-methyl-N-nitrosoamino)-1-(3-pyridinyl)-2-butanone (NNK); polycyclic aromatic hydrocarbon (PAH) benzo[a]pyrene (B[a]P) two its metabolites, (-)-7 beta,8 alpha-dihydroxy-7,8-dihydrobenzo[a]pyrene (7,8-diol) (+)-7 alpha-dihydroxy-9 alpha,10 alpha-oxy-7,8,9,10- tetrahydrobenzo[a]pyrene (BPDE); a complex mixture, an extract subfractions Swedish moist oral snuff (SMOS). Mutagenicity was monitored Ames Salmonella/microsome assays (STY) hprt V79 point mutation assay (V79). effects on in STY were found be complex. In presence either NNN or NNK, low concentrations actually potentiated > 2-fold. However, at higher, but still non-toxic concentrations, decreased both compounds. same type dose-response relationship indicated system DMN, although effect much weaker. results further confirmed replacing another porphyrin compound, hemin. contrast, biliverdin, structure without central metal ion, unable potentiate NNK STY.(ABSTRACT TRUNCATED AT 250 WORDS)