N,N-diethylphenylacetamide, an insect repellent: absence of mutagenic response in the in vitro Ames test and in vivo mouse micronucleus test

N,N-diethylphenylacetamide (DEPA), a promising new insect repellent, was tested for mutagenicity in the in vitro Ames Salmonella/microsome mutagenicity test and the in vivo mouse micronucleus test. For the Ames test, DEPA was assayed both in the presence and absence of Aroclor 1254-induced rat-liver S-9 mix (5 and 20% S-9 fraction), using five tester strains of Salmonella typhimurium--TA97a, TA98, TA100, TA102 and TA104. For the micronucleus test, mice were exposed to DEPA through ip injection for 2 and 5 days in separate experiments, and bone marrow and peripheral blood were sampled 6 and 48 hr after the final injection, respectively. DEPA did not induce a mutagenic response in the Ames test, and mouse bone marrow and peripheral blood micronucleus tests. DEPA was not considered cytotoxic, as a depression of the percentage PCE was not observed at any dose in the range of 1 to 100 mg/kg body weight with either treatment protocol of the micronucleus test.     

3种促智药:石杉碱甲、茴拉西坦和吡乙酰胺的诱变作用和诱变协同作用

在鼠伤寒沙门菌/微粒体系统中测试了石杉碱甲、茴拉西坦和吡乙酸胺的诱变作用。结果表明,药物浓度从1μg-5mg/皿对TA97、TA98、TA100和TA1024个菌株,在无S_9代谢系统上所测的这3个药和有S_9代谢系统所测的石杉碱甲、茴拉西坦均未显示任何诱变作用。向拉西坦和吡乙酰胺在诱变协同实验中均不增加对-硝基喹啉在TA98上和甲基磺酸甲酯在TA100上诱发的回变数。ICR纯系小鼠骨髓微核试验,剂量高达1/2LD_(50)时不增加嗜多染红细胞的微核率,也无骨髓抑制作用.     

赤苷脉通注射液的致突变研究

目的探讨中药制剂赤苷脉通注射液的致突变性。方法采用鼠伤寒沙门氏组氨酸营养缺陷型菌株回复突变实验(Ames实验)、中国仓鼠肺成纤维细胞(CHL)染色体畸变实验和小鼠骨髓微核实验来检测赤苷脉通注射液的致突变作用。结果 Ames实验中,赤苷脉通注射液在312.5～5 000μg.皿-1剂量范围内,无论加或不加S9,鼠伤寒沙门氏菌组氨酸缺陷型TA97,TA98,TA100,TA102和TA1535 5株菌的回复突变菌落数均未出现剂量依赖性的增加;染色体畸变实验中,非活化条件或代谢活化条件下,药物质量浓度为1 200,600和300μg.mL-1时,细胞的染色体畸变率均未出现剂量依赖性增加;微核实验中,在1 150,575和287.5mg.kg-1剂量组中均未见骨髓中含微核的嗜多染红细胞数增加。结论在该实验室条件下,Ames实验、CHL细胞染色体畸变实验和小鼠骨髓微核实验结果均为阴性,即中药制剂赤苷脉通注射液无潜在的遗传毒性。     

松针汁的毒性及致突变性研究

对松针汁进行了毒性和致突变性实验。结果显示：松针汁急性毒性试验，ＬＤ５０〉１０ｇ／ｋｇｂｗ；在所示剂量范围内，Ａｍｅｓ试验加与不加Ｓ９活化系统，各剂量组平均回主率均〈２，小鼠骨髓细胞微核试验，各剂量组微核率与阴性对照组比较无明显差异，小鼠精子畸形试验，各剂量组精子畸形率与阴性对照组比较无明业差异，表明松针汁无毒，无致突变作用。     

二乙基二硫代氨基甲酸钠抑制顺铂的致突变作用

二乙基二硫代氨基甲酸钠（ＤＤＴＣ）能明显抑制顺铂诱导鼠伤寒沙门氏菌ＴＡ１００，ＴＡ９８回变，有Ｓ９代谢活化系统时抑制作用增强，１６０．７４μｇ／ｐｌａｔｅＤＤＴＣ对０．２５～２．００μｇ／ｐｌａｔｅ顺铂抑制率为８７．４％～９５．７％（ＴＡ１００）和８９．４％～１０５．５％（ＴＡ９８）．小鼠ｉｐ顺铂１．５ｍｇ·ｋｇ－１，２４ｈ重复ｉｐ１次，每次给顺铂后１ｈｉｐＤＤＴＣ４００～８００ｍｇ·ｋｇ－１或同时ｉｇＤＤＴＣ７５０～１５００ｍｇ·ｋｇ－１．可显著降低顺铂诱发小鼠骨髓多染红细胞微核的形成．体内外实验结果表明ＤＤＴＣ可降低顺铂的致突变作用     

Safety evaluation of polyphenols extracted from hop bracts.

Hop bract polyphenols contain polyphenols as promising functional ingredients. To assess the safety of topical hop bract polyphenols, Hopsphenon, we examined acute, 14-day, 28-day and 90-day toxicity tests in rats, and mutagenicity tests using Ames test and micronucleus test in mice. The acute, 14-day, 28-day and 90-day toxicity tests revealed that Hopsphenon produced no symptoms of significant injury. The lethal dose of hop bract polyphenols is greater than 2000 mg/kg. The Ames test in the absence of S9 mix for TA98 and in the presence of S9 mix for TA1537 revealed that Hopsphenon had slight mutagenicity at a high dose of 5000 microg/plate; however, in the micronucleus test, Hopsphenon was negative. These tests demonstrated that hop bract polyphenols are safe and do not cause any detrimental effects in vivo under the conditions investigated in this study.     

聚乙二醇修饰降纤酶的遗传毒性评价

目的检测聚乙二醇修饰降纤酶的遗传毒性。方法应用鼠伤寒沙门菌回复突变试验(Ames试验)、体外培养CHO细胞染色体畸变试验和小鼠骨髓微核试验检测聚乙二醇修饰降纤酶的遗传毒性。结果 Ames试验结果显示每平皿100、20、4、0.8、0.16 U各个剂量组,在加或不加S9代谢活化系统时对组氨酸缺陷型鼠伤寒沙门菌TA97、TA98、TA100、TA102及TA1535所诱发的回复突变菌落数均与溶剂对照的突变菌落数相近。体外培养CHO细胞染色体畸变试验结果显示2.5、5.0和10.0 U.mL-1各个剂量组在加S9代谢活化系统于24 h和不加S9代谢活化系统于24 h、48 h培养的CHO细胞染色体畸变率与溶剂对照组比较均无显著差异(P>0.05)。小鼠骨髓微核试验显示425、850、1700 U.kg-1各个剂量组对ICR小鼠的微核诱发率与溶剂对照组比较均无显著差异(P>0.05)。结论聚乙二醇修饰降纤酶对鼠伤寒沙门菌无致突变性,对哺乳动物培养细胞的染色体无致畸变作用,对ICR小鼠无诱发骨髓嗜多染红细胞微核的效应。表明聚乙二醇修饰降纤酶在本实验条件下无遗传毒性。     

油松花粉遗传毒性研究

目的 探讨油松花粉的遗传毒性,为其应用提供安全性毒理学评价依据.方法 用鼠伤寒沙门细菌营养缺陷型突变株TA97(a)、TA 98、TA 100和TA 102,采用平皿掺入法进行Ames实验,将实验分为加和不加代谢激活系统S9 2组平行实验.受实物设5个剂量组(0.008、0.040、0.200、1.000、5.000 mg/皿).应用小鼠骨髓嗜多染红细胞微核实验,检测小鼠骨髓嗜多染红细胞微核率;利用小鼠精子畸形实验,观察不同浓度的油松花粉致小鼠精子畸形的数目.结果 在Ames实验中,油松花粉各剂量组引起的回变菌落数未超过对照组自发回变菌落数的1倍以上;小鼠骨髓嗜多染红细胞微核实验显示,油松花粉3个剂量组的微核发生率均在正常范围内,与阴性对照组比较差异无显著性(P＞0.05),与阳性对照组比较差异显著(P＜0.05);小鼠精子畸形实验显示,油松花粉3个剂量组的精子畸形率均在正常范围内,与阴性对照组比较差异无显著性(P＞0.05),与阳性对照组比较差异显著(P＜0.05).结论 油松花粉对所实菌株、小鼠体细胞及生殖细胞无诱变性.     

Study of mutagenicities of phthalic acid and terephthalic acid using in vitro and in vivo genotoxicity tests

Genotoxicities of phthalic acid (PA) and terephthalic acid (TPA) were examined using three mutagenicity tests: Ames, chromosome aberration (CA), and micronucleus (MN). In the Ames test, these two agents did not produce any mutagenic responses in the absence or presence of S9 mix on the Salmonella typhimurium strains TA98, TA100, TA102, TA1535, or TA1537. The CA test also showed that PA and TPA exerted no significant cytogenetic effect on Chinese hamster ovary (CHO) cells. In the mouse MN test, no significant alteration in occurrence of micronucleated polychromatic erythrocytes was observed in ICR male mice ip administered any of these agents at doses of 0, 20, 100, 500, 2500 or 12,500 microM/kg. These results indicate that PA and TPA produced no mutagenic effects using these in vitro and in vivo mutagenic test systems.     

Mutagenicity and clastogenicity of native airborne particulate matter samples collected under industrial,urban or rural influence

Airborne particulate matter has recently been classified by the IARC as carcinogenic to humans (group 1). However, the link between PM chemical composition and its carcinogenicity is still unclear. The aim of the present study was to evaluate and to compare genotoxic potencies of 6 native PM samples collected in spring–summer or autumn–winter, either in industrial, urban or rural area. We evaluated their mutagenicity through Ames test on YG1041, TA98, and TA102 tester strains, and their clastogenicity on human bronchial epithelial BEAS-2B cells using comet assay, γ-H2AX quantification, and micronucleus assay. Ames test results showed a strong positive response, presumably associated with nitro-aromatics content. In addition, at least 2 positive responses were observed out of the 3 genotoxicity assays for each of the 6 samples, demonstrating their clastogenicity. Our data suggest that PM samples collected in autumn–winter season are more genotoxic than those collected in spring–summer, potentially because of higher concentrations of adsorbed organic compounds. Taken together, our results showed the mutagenicity and clastogenicity of native PM_2.5 samples from different origins, and bring additional elements to explain the newly recognized carcinogenicity of outdoor air pollution.     

Comparative studies on the mutagenicity of pirenzepine with submammalian/bacterial and mammalian systems

The generic pirenzepine was tested for mutagenicity by bacterial and mammalian procedures. In the Ames test the strains of Salmonella typhimurium TA 1535, TA 1537, TA 1538, TA 98, TA 100, and Escherichia coli WP2 (P) were used in the absence and presence of mammalian metabolizing systems. Pirenzepine induced neither base-pair substitutions nor frameshift mutations up to a concentration of 3000 μg/plate. The results of the micronucleus test as well as in vivo cytogenetic analysis of both bone marrow and germ cells in Chinese hamsters were negative after twofold applications of 10, 100, and 1000 mg/kg pirenzepine. No dominant-lethal effects were found after a single treatment of male mice with the same doses.     

Anti-clastogenic effect of magnolol on benzo(a)pyrene-induced clastogenicity in mice.

It was previously reported that magnolol strongly inhibited the mutagenicity induced by the indirect mutagens [benzo(a)pyrene (B(a)P), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-aminodipyrido[1,2-a:3',2'-d]imidazole (Glu-P-2), 2-aminoanthracene (2AA), and 7,12-dimethylbenz[a]anthracene (DMBA)] in Salmonella typhimurium TA98 and TA100 in the Ames test, and that the mechanism of this anti-mutagenic effect may involve the inhibition of the metabolic activation of indirect mutagen enzymes. In this study, the in vivo anti-clastogenic effect of magnolol against clastogenicity induced by B(a)P was evaluated using the micronucleus test in mice. Animals were treated with an oral administration of magnolol (1, 10, and 100 mg/kg) at -24, 0, 24, 48, 72, and 96 h before a single intraperitoneal injection of B(a)P. Peripheral blood specimens were prepared 48 h after administration of B(a)P, and analyzed by the acridine orange (AO) technique. The results indicated that magnolol inhibited clastogenicity induced by B(a)P at various administration times. In order to elucidate the mechanism behind this effect, we measured the activity of the detoxifying enzymes [UDP-glucuronosyltransferase (UGT) and glutathione-S-transferase (GST)] and antioxidative enzymes [superoxide dismutase (SOD) and catalase] in the liver when treated with an oral administration of magnolol at various administration times. Its effect on clastogenicity created by exposure to oxidative DNA damage-inducing X-ray irradiation was also evaluated using the micronucleus test in mice. Results showed that magnolol increased the activity of both UGT and SOD enzymes, and also inhibited the clastogenicity induced by X-ray irradiation. Magnolol had an anti-clastogenic effect on B(a)P in the micronucleus test as well as an anti-mutagenic effect on indirect mutagens in the Ames test. The anti-clastogenic effect of magnolol was also suggested by the increases in UGT and SOD enzyme activity, and by the attenuation of oxidative damage induced by X-ray irradiation.     

Mutagenicity of cisplatin and carboplatin used alone and in combination with four other anticancer drugs

Mutagenicity of cisplatin and carboplatin was compared by using the drugs alone and in combination with bleomycin, 5-fluorouracil, vincristine and methotrexate in the Ames Salmonella assay employing the tester strains TA98, TA100 (excision deficient) and TA102 (excision proficient). Cisplatin showed the maximum yield of histidine revertants in TA98 and TA100 at 2 micrograms/plate followed by a decrease in the number of mutants/plate with increasing concentrations. In the excision proficient strain TA102, there was no decline in the number of mutants/plate even at a concentration of 8 micrograms/plate. Basically, similar results were also obtained with carboplatin but using higher concentrations of the drug. When cisplatin or carboplatin was combined with other anticancer drugs, there was no differential modification of mutagenicity of the 2 platinum compounds in any of the bacterial tester strains.     

Genotoxicity of quinocetone,cyadox and olaquindox in vitro and in vivo

Quinocetone (QCT) and Cyadox (CYA) are important derivative of heterocyclic N-oxide quinoxaline (QdNO), used actively as antimicrobial feed additives in China. Here, we tested and compared the genotoxic potential of QCT and CYA with olaquindox (OLA) in Ames test, HGPRT gene mutation (HGM) test in V79 cells, unscheduled DNA synthesis (UDS) assay in human peripheral lymphocytes, chromosome aberration (CA) test, and micronucleus (MN) test in mice bone marrow. OLA was found genotoxic in all 5 assays. In Ames test, QCT produced His⁺ mutants at 6.9 μg/plate in Salmonella typhimurium TA 97, at 18.2 μg/plate in TA 100, TA 1535, TA 1537, and at 50 μg/plate in TA 98. CYA produced His⁺ mutants at 18.2 μg/plate in TA 97, TA 1535, and at 50 μg/plate in TA 98, TA 100 and TA 1537. QCT was found positive in HGM and UDS assay at concentrations ⩾10 μg/ml while negative results were reported in CA test and MN test. Collectively, we found that OLA was more genotoxic than QCT and CYA. Genotoxicity of QCT was found at higher concentration levels in Ames test, HGM and UDS assays while CYA showed weak mutagenic potential to bacterial cells in Ames test.     

Absence of mutagenicity of acid pyrogallol-containing hair gels.

In the present work, three commercial acid (pH 3.5-4) pyrogallol-containing hair gels, SunSet Alizador Negro (two formulations) and Embelleze Henê Gel, were tested for mutagenicity using two well-established assays. In the Salmonella mutagenicity assay using 648-5000 microg/plate of cosmetic samples, none of the samples reached a 2-fold increase in revertants relative to the controls. Both in the absence and in the presence of S9, the dose-response relation in strains TA98, TA100, TA102, TA1535, and TA1537 was not significant (p>0.01). In the mouse bone marrow micronucleus assay, 10 Swiss male mice were orally administered 2000 mg/kg of sample per body weight/day. The ratio between polychromatic and normochromatic erythrocytes as well as the presence of micronuclei in bone marrow cells were determined. Equal numbers of micronucleated polychromatic erythrocytes were detected between the cells of each treated group and the negative control, using ANOVA and chi-square analyses. Thus, none of the products induced mutagenesis in either assay. Previous studies have shown pyrogallol is mutagenic in various test systems, including Salmonella. However studies have also shown that acidic conditions may repress the reactive-oxygen species (ROS) produced by pyrogallol, and ROS is considered the primary mechanism for the mutagenicity of pyrogallol. Consistent with this are our results, which show that acidic, commercially available pyrogallol-containing hair gels are neither mutagenic in Salmonella nor induce micronuclei in mouse bone marrow in vivo.     

Mutagenicity studies on dihydroergocristine

Dihydroergocristine (DHEC) is an ergot derivative used for the therapy of patients with cerebrovascular insufficiency. It was tested for mutagenicity by means of four tests. In the mutagenicity in vitro assay on Salmonella typhimurium, DHEC was checked at 10,000 micrograms/plate on TA98 and TA1538 strains and at 3000 micrograms/plate on TA1535, TA1537 and TA100 strains with and without metabolic activation. In a quantitative in vitro test for mutagenicity in V79 Chinese hamster cells, DHEC was studied at concentrations between 30 and 0.3 microgram/ml with and without metabolic activation. DHEC was tested for its ability to induce chromosomal damage in human lymphocyte cultures utilizing the concentrations of 10, 3 and 1 microgram/ml. In the in vivo mouse (Swiss strain) micronucleus assay, DHEC was orally administered at two dosages (50% and 16% of LD50) following the schedule of the test. Dihydroergocristine is a drug free of mutagenic activity on the basis of all the results obtained from the above in vitro and in vivo tests.     

不同水处理工艺的自来水出厂水中有机物的遗传毒性

目的检测和评价某市6家A,B,C,D,E和F厂采用不同水处理工艺自来水厂出厂水中有机物的遗传毒性。方法通过鼠伤寒沙门菌致突变实验、微核实验及微量波动实验检测与比较各水样中有机物的致突变性。结果 6家自来水厂出厂水中有机物的鼠伤寒沙门菌致突变实验结果均为阳性;各厂出厂水中有机物诱导的小鼠骨髓细胞微核率由高至低依次为:D>E=A>C>F>B;C厂后加氯单元出水中有机物在每板0.25 L的剂量下,微量波动实验对于TA98,TA100均出现阳性结果,并且各剂量的阳性反应孔存在明显的剂量反应关系(P<0.05)。结论某市6家自来水厂出厂水中的有机物具有明显的致突变作用,且以移码突变为主;微核实验与Ames实验对水中有机物遗传毒性检测与评价结果基本一致;微量波动实验可提高对水中有机物致突变性检测的灵敏度。     

Tinospora cordifolia, a safety evaluation

Tinospora cordifolia is one of the indispensable medicinal plants used in veterinary folk medicine/Ayurvedic system of medicine for the treatment of diverse diseases and recommended for improving the immune system by means of body resistance. In the current study, we evaluated the genotoxic risk of the aqueous extract of T. cordifolia (TC) in a battery of four different genotoxicity tests viz., Ames, in vitro chromosome aberration (CA), rodent bone marrow micronucleus (MN), and Comet assay. Experimental results confirmed that in Ames test up to 5000 μg/plate of TC did not exhibit any mutagenic effect in Salmonella typhimurium mutant strains (TA97a, TA98, TA100, TA102, and TA1535). In CA assay, TC was not clastogenic to human peripheral blood lymphocytes up to a concentration of 3000 μg/ml. In MN and Comet assays, TC was pre-treated for 7 days at three dose levels (150, 200 and 250 mg/kg body weight) orally to male Balb/c mice. The results showed that TC treatment did not display clastogenicity and DNA damaging effect in bone marrow erythrocytes and peripheral blood lymphocytes respectively.     

Monitoring sãto paulo state rivers in brazil for mutagenic activity using the ames test

Organic extracts of raw water from 11 water courses of São Paulo State, Brazil, were collected during one year bimonthly and tested for mutagenicity using the Ames test, with strains TA98 and TA100 of Salmonella typhimurium with and without metabolic activation. The samples were extracted with XAD₂ resin and eluted with methanol and methylene chloride. From the 75 samples analyzed, 14 showed positive responses and 8 were considered marginal, making up 29% of mutagenic samples. The percentage of mutagenic samples in October (spring) was 9%, increasing to 64% in February (summer), and decreased to 9% again in August (winter). Paraiba do Sul river showed the higher percentage of mutagenic samples (67%) and Capivari river the highest mutagenic sample (1787 and 3265 revertants per liter for TA98 without and with S9, respectively). The amplitude of the mutagenic response was 39–3265 revertants per liter for TA98 and 83–467 for TA100. The mutagenic samples showed direct and indirect mutagens, and TA98 detected the majority of responses, indicating prevalence of frameshift mutagens in these samples. © 1993 John Wiley & Sons, Inc.     

白障明的诱变性试验研究

作者用鼠伤寒沙门氏菌回变试验,小鼠骨髓红细胞微核试验及CHL细胞染色体畸变试验,对白障明进行了诱变性试验研究。结果表明鼠伤寒沙门氏菌回变试验为阴性,该药可能不诱发基因突变,NIH小鼠骨髓红细胞微核试验及CHL细胞染色体畸变试验均为阴性,说明该药可能不诱发体内,体外染色体损伤作用。