TY - JOUR
T1 - Inhibition of 2-Amino-3,8-dimethylimidazo[4,5-f]quinoxaline-mediated DNA-adduct formation by chlorophyllin in Drosophila
AU - Sugiyama, Chitose
AU - Shinoda, Aki
AU - Hayatsu, Hikoya
AU - Negishi, Tomoe
PY - 1996/4
Y1 - 1996/4
N2 - The effect of chlorophyllin on 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx)-mediated DNA-adduct formation in Drosophila was studied. Third-instar larvae of Drosophila were fed MeIQx at 1 mg/6.5 g-feed/bottle, with or without chlorophyllin (100-300 mg). After a 6 h feeding exposure to MeIQx, the larvae were divided into 2 groups. The first group was examined for covalent DNA adducts by 32P-postlabeling assay. The second group was assayed for DNA damage by allowing the larvae to develop to adults and measuring the male/female ratio (males, DNA repair-deficient; females, DNA repair-proficient). The 32P-postlabeling results indicated a significant decrease in DNA adduct levels in larvae treated with MeIQx and 300 mg chlorophyllin (1.7±0.7 adducts/107 nucleotides) as compared with MeIQx-treated larvae (6.5±2.1 adducts/107 nucleotides). The results on male/female sex ratios also indicated a chlorophyllin-induced decrease in DNA damage by exposure to MeIQx. The suppressive effect of chlorophyllin on the genotoxic actions of a polycyclic mutagen, MeIQx, may be a result of complex formation between chlorophyllin and the mutagen.
AB - The effect of chlorophyllin on 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx)-mediated DNA-adduct formation in Drosophila was studied. Third-instar larvae of Drosophila were fed MeIQx at 1 mg/6.5 g-feed/bottle, with or without chlorophyllin (100-300 mg). After a 6 h feeding exposure to MeIQx, the larvae were divided into 2 groups. The first group was examined for covalent DNA adducts by 32P-postlabeling assay. The second group was assayed for DNA damage by allowing the larvae to develop to adults and measuring the male/female ratio (males, DNA repair-deficient; females, DNA repair-proficient). The 32P-postlabeling results indicated a significant decrease in DNA adduct levels in larvae treated with MeIQx and 300 mg chlorophyllin (1.7±0.7 adducts/107 nucleotides) as compared with MeIQx-treated larvae (6.5±2.1 adducts/107 nucleotides). The results on male/female sex ratios also indicated a chlorophyllin-induced decrease in DNA damage by exposure to MeIQx. The suppressive effect of chlorophyllin on the genotoxic actions of a polycyclic mutagen, MeIQx, may be a result of complex formation between chlorophyllin and the mutagen.
KW - Chlorophyllin
KW - MeIQx
KW - MeIQx-DNA adduct
KW - P-Postlabeling of Drosophila DNA
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U2 - 10.1111/j.1349-7006.1996.tb00224.x
DO - 10.1111/j.1349-7006.1996.tb00224.x
M3 - Article
C2 - 8641960
AN - SCOPUS:0029871426
SN - 0910-5050
VL - 87
SP - 325
EP - 328
JO - Japanese Journal of Cancer Research
JF - Japanese Journal of Cancer Research
IS - 4
ER -