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Antimutagenic activity of active ingredients in sho-saiko-to
223 ronmental Protection Agency, Research Triangle Park, NC 27709, USA
Possible induction of lung cancer by nitro aromatic hydrocarbons in particulate pollutants Carcinogenic nitroarenes were detected in the resected lung of a patient with lung cancer. It was concluded that the presence of nitropyrenes might have played an initiating role and the resulting tumor was also due to expose to by-products of combustion of heavy oil. The patient was a nonsmoker and farmer who had bred chickens for 40 years. He used heavy oil for heating the chicken house. Similarly, a group of Chinese people at high risk of developing lung cancer was selected to determine the underlying cause. Lung cancers were obtained from six Chinese female nonsmokers who were living in Fuyuan County, China. Polycyclic aromatic hydrocarbons were detected in resected lung specimens, including benzo[ k ]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene and pyrene. These cases were associated with exposure to soot from combustion of coal usually for heating and cooking indoors. These results suggest that the detected mutagens and carcinogens participated in the initiation of the cancers. The validity of this hypothesis for the induction of lung cancer requires confirmation of DNA adducts from these chemicals in specimen material. Nitroarenes are produced and contaminate urban air as pollutants wherever fossil fuels are used.
74 Kataoka, K. ", T. Kinouchi ~, H. Arimochi", S.M. Shaheduzzaman ~, J. Purintrapiban ~, U. Vinitketkumnuen b, Y. Ohnishi a, ~Department of Bacteriology, School of Medicine, The University of Tokushima, 3-18-15, Kuramoto-cho, Tokushima-shi, Tokushima 770, Japan, bDepartment of Biochemistry, Faculty of Medicine, Chiang Mai University, Chiang mai 5000, Thailand
Inhibitory effect of caraway seeds on the mutagencity induced by MNNG A hot water extract of caraway seeds, a kind of spice, inhibited the mutagenicity induced by Nmethyl-N'-nitro-N-nitrosoguanidine (MNNG) and the
formation of 1,2-dimethylhydrazine-induced aberrant crypts in the rat colon. To elucidate the mechanism of antimutagenic action of caraway seeds, we used Sahnonella o,phimurium O6-methylguanine-DNA methyltransferase-deficient and -proficient strains YG7108 (ada- ogt-), YG7104 (ada + ogt-), YG7100 (ada- ogt+), TA100 (ada + ogt +) and TA1535 (ada + ogt +) for the antimutagenicity assay. The caraway extract was antimutagenic for ogt + strains but not antimutagenic for ogt- strains treated with MNNG. The decrease in MNNG-induced mutagenicity required simultaneous treatment of MNNG with the extract. The amount of O6-methylguanine in strain YGTI00 (ada- ogt*) treated with 10 ~ g / m l MNNG at 37°C for 60 rain was 59.0 pmol/100 /xg DNA but decreased by 70 percent in the presence of the extract. These results suggest that antimutagenic activity of caraway seeds is influenced by Ogt protein reducing O6-methylguanines in DNA.
75 Ohtsuka, M. ~'b, Y. Koda a, H. Yano b, M. Kojiro", aHita Research Laboratories, Chemicals Inspection and Testing Institute, 3-822, Ishiimachi, Hita, Oita 877, b Kurume University School of Medicine, First Department of Pathology, 67, Asahi-machi, Kurume, Fukuoka 830, Japan Antimutagenic activity of active ingredients in sho-saiko-to Sho-saiko-to, a traditional Chinese medicine, is clinically reported to suppress development of liver cancer, but its mode of suppression has not been fully elucidated. We examined inhibition and suppression of furylfulamide (AF-2)-induced mutagenesis in Salmonella t3,phimurium TA100 by sho-saikoto (TJ-9, Tsumura & Co.) and its 9 active ingredients. Active ingredients of TJ-9 can be classified, mainly, into saponins and flavonoids. The present study examined, from the former group, saikosaponin a, c and d; glycyrrhizin; ginsenoside Rbl and Rgl; and from the latter group, baicalein, baicalin and wogonin. In the mutagen inactivation test, mixtures containing TJ-9 (or each active ingredient) with AF2 were incubated at 37°C for 20 rain, and then the Ames test was conducted. In the mutation suppression test, TJ-9 (or each
224
active ingredient) was added to the cell suspension of TAI00, which was pretreated with AF-2, and then the Ames test was conducted. As a result, TJ-9 did not inhibit the activity of AF-2 or suppress AF-2-induced mutagenesis, while saikosaponin a suppressed mutation by approximately 50%, ginsenoside Rbl inhibited by approximately 30% and suppressed by approximately 50%. In addition, suppression effects of ginsenoside Rbl increased dose-dependently. These findings indicate that TJ-9 may have the ability to suppress hepatic cancer development by suppressing mutation.
76 Mitsuo Miyazawaa, Hideo ShimamurW, Sei-ichi Nakamurab, Hiromu Kameokaa, aDepartment of Applied Chemistry, Faculty of Science and Engineering, Kinki University, Kowakae, Higashiosaka-shi, Osaka 577, Japan, bOsaka Prefectural Institute of Public Health, Nakamichi-l, Higashinari-ku, Osaka 537, Japan
Antimutagenic activity of isofraxineilone from Dictamnus dasycarpus A dichloromethane extract from Dictamunus dasycarpus showed a suppressive effect on umu gene expression of the SOS response in Salmonella thyphimurium TAI535/pSK1002 against the mutagem 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (furylfuramide). The suppressive compound in the dichloromethane extract from D. dasycarpus was isolated by S i O 2 column chromatography, and identified as isofraxinellone by EI-MS, IH and 13C NMR spectroscopy. Isofraxinellone exhibited an inhibition of the SOS inducing activity of furylfuramide in the umu test. Gene expression was suppressed completely at less than 0.86 /,mol/ml, and the IDs0 value was 0.35 /*mol/ml. Fraxinellone, which was one of the major components in D. dasycarpus, was also isolated, but this compound did not show any suppressive effect on the SOS induction of furylfuramide. Isofraxinellone was also assayed with the mutagen (3-amino- 1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1)) which requires liver metabolizing enzymes, and showed a suppressive effect similar to that with furylfuramide. Its IDs0 value against Trp-P1 was 0.50 #mol/ml. The antimutagenic activities
of isofraxinellone against furylfuramide and Trp-P-1 were tested by an Ames test using Salmonella thyphimurium TAI00; which indicated that isofraxinellone showed antimutagenic activity.
77 Motohashi, N. a, C. Yamagami ~, Y. Saito b, aKobe Pharmaceutical University, 4-19-I, Motoyamakitamachi, Higashinada-ku, Kobe 658, bFaculty of Parmaceutical Science, Okayama University, 1-1-1, Tsushima-Naka, Okayama 700, Japan
Antimutagenic effects of dehydrozingerone-related compounds It has been reported that curcumin (I) and dehydrozingerone (II) scavenge active oxygen radicals and inhibit inflammation and lipid peroxidation. In this study, we prepared III-V and X compounds by the Claisen Schmidt reaction and examined the antimutagenic activity of curcumin, dehydrozingerone, the synthetic compounds and cinnamic derivatives (VI-IX) in relation to their structures.
RI
R , - ~ - - C H = C H - R, NO. I
R,
R2
0CH, O H
R~ CO-( ]7 )
[I 0CH~ O H
COCH~
]]I
H
OH
COCH~
IV
H
CH~ COCH~
V
CH,
H
COCH,
VI
H
H
COCH~
VII
H
H
CHO
VI~
H
H
COOH
IX
H
H
CH~
X
H
H
co-(vl )
Bio-antimutagenic activity was assayed by observing mutagenesis induced by UV-irradiation (1 J / m 2) in E. coli WP2 B / r ut,rA trpE. p-Hydroxy (III), p-and m-methyl (IV and V) substituted derivatives and VI decreased the induced mutation frequency, showing the strongest activity (about 80% decrease at 24 /~mol/plate). On the other hand,
Possible induction of lung cancer by nitro aromatic hydrocarbons in particulate pollutants Carcinogenic nitroarenes were detected in the resected lung of a patient with lung cancer. It was concluded that the presence of nitropyrenes might have played an initiating role and the resulting tumor was also due to expose to by-products of combustion of heavy oil. The patient was a nonsmoker and farmer who had bred chickens for 40 years. He used heavy oil for heating the chicken house. Similarly, a group of Chinese people at high risk of developing lung cancer was selected to determine the underlying cause. Lung cancers were obtained from six Chinese female nonsmokers who were living in Fuyuan County, China. Polycyclic aromatic hydrocarbons were detected in resected lung specimens, including benzo[ k ]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene and pyrene. These cases were associated with exposure to soot from combustion of coal usually for heating and cooking indoors. These results suggest that the detected mutagens and carcinogens participated in the initiation of the cancers. The validity of this hypothesis for the induction of lung cancer requires confirmation of DNA adducts from these chemicals in specimen material. Nitroarenes are produced and contaminate urban air as pollutants wherever fossil fuels are used.
74 Kataoka, K. ", T. Kinouchi ~, H. Arimochi", S.M. Shaheduzzaman ~, J. Purintrapiban ~, U. Vinitketkumnuen b, Y. Ohnishi a, ~Department of Bacteriology, School of Medicine, The University of Tokushima, 3-18-15, Kuramoto-cho, Tokushima-shi, Tokushima 770, Japan, bDepartment of Biochemistry, Faculty of Medicine, Chiang Mai University, Chiang mai 5000, Thailand
Inhibitory effect of caraway seeds on the mutagencity induced by MNNG A hot water extract of caraway seeds, a kind of spice, inhibited the mutagenicity induced by Nmethyl-N'-nitro-N-nitrosoguanidine (MNNG) and the
formation of 1,2-dimethylhydrazine-induced aberrant crypts in the rat colon. To elucidate the mechanism of antimutagenic action of caraway seeds, we used Sahnonella o,phimurium O6-methylguanine-DNA methyltransferase-deficient and -proficient strains YG7108 (ada- ogt-), YG7104 (ada + ogt-), YG7100 (ada- ogt+), TA100 (ada + ogt +) and TA1535 (ada + ogt +) for the antimutagenicity assay. The caraway extract was antimutagenic for ogt + strains but not antimutagenic for ogt- strains treated with MNNG. The decrease in MNNG-induced mutagenicity required simultaneous treatment of MNNG with the extract. The amount of O6-methylguanine in strain YGTI00 (ada- ogt*) treated with 10 ~ g / m l MNNG at 37°C for 60 rain was 59.0 pmol/100 /xg DNA but decreased by 70 percent in the presence of the extract. These results suggest that antimutagenic activity of caraway seeds is influenced by Ogt protein reducing O6-methylguanines in DNA.
75 Ohtsuka, M. ~'b, Y. Koda a, H. Yano b, M. Kojiro", aHita Research Laboratories, Chemicals Inspection and Testing Institute, 3-822, Ishiimachi, Hita, Oita 877, b Kurume University School of Medicine, First Department of Pathology, 67, Asahi-machi, Kurume, Fukuoka 830, Japan Antimutagenic activity of active ingredients in sho-saiko-to Sho-saiko-to, a traditional Chinese medicine, is clinically reported to suppress development of liver cancer, but its mode of suppression has not been fully elucidated. We examined inhibition and suppression of furylfulamide (AF-2)-induced mutagenesis in Salmonella t3,phimurium TA100 by sho-saikoto (TJ-9, Tsumura & Co.) and its 9 active ingredients. Active ingredients of TJ-9 can be classified, mainly, into saponins and flavonoids. The present study examined, from the former group, saikosaponin a, c and d; glycyrrhizin; ginsenoside Rbl and Rgl; and from the latter group, baicalein, baicalin and wogonin. In the mutagen inactivation test, mixtures containing TJ-9 (or each active ingredient) with AF2 were incubated at 37°C for 20 rain, and then the Ames test was conducted. In the mutation suppression test, TJ-9 (or each
224
active ingredient) was added to the cell suspension of TAI00, which was pretreated with AF-2, and then the Ames test was conducted. As a result, TJ-9 did not inhibit the activity of AF-2 or suppress AF-2-induced mutagenesis, while saikosaponin a suppressed mutation by approximately 50%, ginsenoside Rbl inhibited by approximately 30% and suppressed by approximately 50%. In addition, suppression effects of ginsenoside Rbl increased dose-dependently. These findings indicate that TJ-9 may have the ability to suppress hepatic cancer development by suppressing mutation.
76 Mitsuo Miyazawaa, Hideo ShimamurW, Sei-ichi Nakamurab, Hiromu Kameokaa, aDepartment of Applied Chemistry, Faculty of Science and Engineering, Kinki University, Kowakae, Higashiosaka-shi, Osaka 577, Japan, bOsaka Prefectural Institute of Public Health, Nakamichi-l, Higashinari-ku, Osaka 537, Japan
Antimutagenic activity of isofraxineilone from Dictamnus dasycarpus A dichloromethane extract from Dictamunus dasycarpus showed a suppressive effect on umu gene expression of the SOS response in Salmonella thyphimurium TAI535/pSK1002 against the mutagem 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (furylfuramide). The suppressive compound in the dichloromethane extract from D. dasycarpus was isolated by S i O 2 column chromatography, and identified as isofraxinellone by EI-MS, IH and 13C NMR spectroscopy. Isofraxinellone exhibited an inhibition of the SOS inducing activity of furylfuramide in the umu test. Gene expression was suppressed completely at less than 0.86 /,mol/ml, and the IDs0 value was 0.35 /*mol/ml. Fraxinellone, which was one of the major components in D. dasycarpus, was also isolated, but this compound did not show any suppressive effect on the SOS induction of furylfuramide. Isofraxinellone was also assayed with the mutagen (3-amino- 1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1)) which requires liver metabolizing enzymes, and showed a suppressive effect similar to that with furylfuramide. Its IDs0 value against Trp-P1 was 0.50 #mol/ml. The antimutagenic activities
of isofraxinellone against furylfuramide and Trp-P-1 were tested by an Ames test using Salmonella thyphimurium TAI00; which indicated that isofraxinellone showed antimutagenic activity.
77 Motohashi, N. a, C. Yamagami ~, Y. Saito b, aKobe Pharmaceutical University, 4-19-I, Motoyamakitamachi, Higashinada-ku, Kobe 658, bFaculty of Parmaceutical Science, Okayama University, 1-1-1, Tsushima-Naka, Okayama 700, Japan
Antimutagenic effects of dehydrozingerone-related compounds It has been reported that curcumin (I) and dehydrozingerone (II) scavenge active oxygen radicals and inhibit inflammation and lipid peroxidation. In this study, we prepared III-V and X compounds by the Claisen Schmidt reaction and examined the antimutagenic activity of curcumin, dehydrozingerone, the synthetic compounds and cinnamic derivatives (VI-IX) in relation to their structures.
RI
R , - ~ - - C H = C H - R, NO. I
R,
R2
0CH, O H
R~ CO-( ]7 )
[I 0CH~ O H
COCH~
]]I
H
OH
COCH~
IV
H
CH~ COCH~
V
CH,
H
COCH,
VI
H
H
COCH~
VII
H
H
CHO
VI~
H
H
COOH
IX
H
H
CH~
X
H
H
co-(vl )
Bio-antimutagenic activity was assayed by observing mutagenesis induced by UV-irradiation (1 J / m 2) in E. coli WP2 B / r ut,rA trpE. p-Hydroxy (III), p-and m-methyl (IV and V) substituted derivatives and VI decreased the induced mutation frequency, showing the strongest activity (about 80% decrease at 24 /~mol/plate). On the other hand,