Effects of natamycin on sister chromatid exchanges,chromosome aberrations and micronucleus in human lymphocytes

Natamycin (pimaricin) (E235) is an antifungal that can be used as an antibiotic to treat most fungus infections. It has been globally used in a variety of foods and beverages. In the present study, the effects of natamycin on chromosome aberrations (CAs), sister chromatid exchanges (SCEs), and micronucleus (MN) formation in human lymphocytes cells were investigated. The human lymphocytes were treated with 13, 18, 23, and 28 μg/mL of natamycin for 24 and 48 h. Natamycin induced the SCE frequency at the highest concentration for 48 h only; however, it induced the structural CA and MN frequency at all concentrations when compared to control and at all concentrations, except the lowest concentration (13 μg/mL), when compared to solvent control. Natamycin showed a cytotoxic effect by decreasing the replication index, mitotic index, and nuclear division index (NDI), especially at the highest concentrations for two treatment periods.     

The Effects of Food Protector Biphenyl on Sister Chromatid Exchange,Chromosome Aberrations,and Micronucleus in Human Lymphocytes

The aim of this study was to determine the possible genotoxic effects of biphenyl (E230), which is used as an antimicrobial agent in food by using sister chromatid exchanges (SCEs), chromosome aberrations (CAs), and micronucleus (MN) tests in human peripheral lymphocytes. The human peripheral lymphocytes were treated with four concentrations of biphenyl (10, 30, 50, and 70 μg/mL) for 24- and 48-h treatment periods. In the present study, biphenyl significantly increased the frequency of SCEs, CAs, and the frequency of MN when compared with both untreated control and solvent (dimethyl sulfoxide) control. The inductions of these abnormalities were in a dose-dependent manner. Biphenyl was capable to induce the structural CAs instead of numerical CAs. Biphenyl also showed a cytotoxic effect by decreasing the replication index at the highest two concentrations for 48 h and nuclear division index at the highest two concentrations for the 24- and 48-h treatment periods. However, biphenyl did not affect the mitotic index (MI).     

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。     

Genotoxicity of Aspartame

In the present study, the genotoxic effects of the low‐calorie sweetener aspartame (ASP), which is a dipeptide derivative, was investigated using chromosome aberration (CA) test, sister chromatid exchange (SCE) test, micronucleus test in human lymphocytes and also Ames/Salmonella/ microsome test. ASP induced CAs at all concentrations (500, 1000 and 2000 µg/ml) and treatment periods (24 and 48 h) dose‐dependently, while it did not induce SCEs. On the other hand, ASP decreased the replication index (RI) only at the highest concentration for 48 h treatment period. However, ASP decreased the mitotic index (MI) at all concentrations and treatment periods dose‐dependently. In addition, ASP induced micronuclei at the highest concentrations only. This induction was also dose‐dependent for 48 hours treatment period. ASP was not mutagenic for Salmonella typhimurium TA98 and TA100 strains in the absence and presence of S9 mix.     

The Cytogenetic Effects of Food Sweetener Maltitol in Human Peripheral Lymphocytes

The effects of the low-calorie artifical sweetener maltitol (E965), a sugar alcohol (Polyol), on sister chromatid exchange (SCE), chromosome aberration (CA), and micronucleus formation (MN) were investigated in human peripheral lymphocytes. Maltitol did not induce SCE at all concentrations (1.25, 2.5, and 5 mg/mL) and treatment periods (24 and 48 h). Maltitol induced CA, although not statistically significantly. Maltitol induced the frequency of MN at 24 and 48 h in a non-dose-dependent manner. In addition, maltitol did not decrease the replication index (RI) and the mitotic index (MI) at all concentrations and treatment periods. Maltitol did not alter the pH and osmolality of the medium. In conclusion, it can be concluded that maltitol has a weak genotoxic potential and it appears non-cytotoxic to human peripheral lymphocytes in vitro.     

Developmental toxicity and genotoxicity studies of wogonin

We studied the developmental toxicities and genotoxic potency of a widely bioactive plant medicine-wogonin in vivo and in vitro. In the in vivo developmental experiments, high dose of wogonin (40mg/kg, intravenous injection) significantly induced the maternal weight gains and affected fetus including bodyweight, resorptions, live birth index and fetal skeletal alterations. In Ames test, no concentration-dependently increased TA98, TA100, and TA102 revertants were detected in wogonin groups whether in presence of metabolic activating enzymes or not. In the chromosome aberration test, wogonin dose-dependently increased structural chromosomal aberrations in CHL cells both with and without S9, even the effect was all judged (-). In micronucleus assay, no significant changes of MNPCE/PCE and PCE/NCE were found on mouse bone marrow micronucleus in wogonin groups. We concluded that wogonin induced developmental toxicities on pregnant mice and fetus, and the genotoxicities were positive. However no significant malformation was observed and only in vitro potency of chromosome aberration was weak, which suggested us wogonin could be a relatively safe drug in clinic.     

Mutagenicity studies with Praziquantel,a new anthelmintic drug,in mammalian systems

Praziquantel, a new anthelmintic drug with antischistosomal and anticestodal properties, was tested in comparison with a placebo control and a positive control with cyclophosphamide in mammalian test systems in vivo for potential mutagenic effects. The test systems used and the tested doses of Praziquantel were: (1) Dominant lethal test on male NMRI mice, 12 mating periods of 4 days each, 1×1200 mg/kg BW by mouth; (2) Dominant lethal test on female NMRI mice, treatment during pre-estrus, 1×1200 mg/kg BW by mouth; (3) Micronucleus test on male and female NMRI mice, two doses with a 24-h interval and preparation of the femoral marrow 6 h after the second dose, 2 ×300 mg/kg and 2×600 mg/kg BW by mouth; (4) Spermatogonial test on the Chinese hamster, two doses with a 24-h interval and preparation of the spermatogonia 48 h after the second dose, 2×600 mg/kg BW by mouth. The 1200 mg/kg BW dose corresponded to approximately 1/2 of the LD₅₀ after oral application in the mouse and about 40 times the therapeutic dose (1×30 mg/kg BW). The cyclophosphamide doses in the test systems were 1×200 mg/kg or 2 ×200 mg/kg BW by mouth.No indication was found of any mutagenic potency of Praziquantel. This agrees with the results of point-mutation tests done by other authors.

---

Zusammenfassung Praziquantel, ein neues Anthelmintikum mit Antischistosomen- und Anticestodenwirkung, wurde im Vergleich zu einer Placebo-Kontrolle und zu einer Positiv-Kontrolle mit Cyclophosphamid in verschiedenen Säuger-Testsystemen in vivo auf mögliche mutagene Wirkungen untersucht. Die Testsysteme und untersuchten Praziquantel-Dosen waren: (1) Dominant-Letal-Test an der männlichen NMRI-Maus, 12 Paarungsperioden zu je 4 Tagen, 1× 1200 mg/kg KG per os; (2) Dominant-Letal-Test an der weiblichen NMRI-Maus, Applikation im Pro-Oestrus, 1×1200 mg/kg KG per os; (3) Mikronucleus-Test an männlichen und weiblichen NMRI-Mäusen, zweimalige Gabe im Abstand von 24 Std und Aufarbeitung des Femurmarks 6 Std nach der zweiten Applikation, 2×300 mg/kg und 2×600 mg/kg KG per os; (4) Spermatogomen-Test am Chinesischen Hamster, zweimalige Gabe im Abstand von 24 Std und Aufarbeitung der Spermatogonien 48 Std nach der zweiten Applikation, 2 × 600 mg/kg KG per os. Die Dosis 1200 mg/kg KG per os entsprach etwa der halben LD₅₀ nach oraler Gabe an der Maus und ca. dem 40fachen der therapeutischen Dosis (1×30 mg/kg KG per os). Die Cyclophosphamid-Dosen waren in den entsprechenden Testsystemen 1×200 mg/kg bzw. 2×200 mg/kg KG per os.Es fand sich kein Hinweis auf eine mutagene Potenz von Praziquantel. Dies stand im Einklang mit den Ergebnissen von Punktmutations-Tests, die von anderen Autoren durchgeführt worden sind.

     

Mutagenicity tests with astemizole in vitro and in vivo

Possible induction of chromosomal aberrations and/or sister chromatid exchanges by astemizole was studied in vitro on human lymphocytes. In vivo chromosomal damage was assessed by a micronucleus test on rats and a dominant lethal test on both male and female mice. All these tests yielded negative results for astemizole so that it can be concluded that astemizole has no potential to induce chromosomal aberrations.     

子宫内膜癌淋巴细胞染色体不稳定性研究

目的　研究子宫内膜癌患者外周血淋巴细胞染色体不稳定性 ,探讨子宫内膜癌患者外周血淋巴细胞染色体畸变 (CAR)、脆性部位 (fra)、姐妹染色单体交换 (SCE)、微核 (MN )、核仁形成区 (NOR)的相关性。方法　对 19例子宫内膜癌患者外周血培养 ,常规收获细胞 ,制片 ,分别对淋巴细胞染色体 CAR、fra、SCE、MN、NOR检测并进行相关分析。结果　 119例子宫内膜癌患者染色体结构畸变以出现次数的多少排列顺序为 :3、2、1、5、7、17号染色体。 2染色体非二倍体、CAR、fra、SCE频率、MN率、Ag- NOR分别为 2 1.4%、(9.9± 3.5 ) %、7.8%、(7.2± 1.7)次 /细胞、(6 .8± 2 .3)‰、(6 .1± 1.4)个 /细胞。正常对照组为 15 .2、(4 .0± 1.9) %、3.1%、(5 .1± 0 .7)次 /细胞、(2 .2± 1.6 )‰、(5 .3± 1.0 )个细胞。 3染色体 CAR、fra、SCE、MN间相关性分析发现正常对照组CAR与 fra之间呈正相关 ,余各项之间无相关。而子宫内膜癌患者除了 CAR与 MN无相关外 ,各指标之间均呈正相关。结论　子宫内膜癌患者外周血淋巴细胞染色体存在着数目及结构畸变 ,染色体畸变是导致子宫内膜癌发生的重要原因。肿瘤患者淋巴细胞染色体不稳定性的发生是其必然的表现 ,通过对高危人群进行染色体不稳定性检测有助于筛查高危患者。     

Podophyllin,but not the constituents quercetin or kaempferol,induced genotoxicity in vitro and in vivo through ROS production

The genotoxic potential of podophyllin (PD) was investigated in this study. PD increased bacterial revertants and abnormal chromosomal structures in a concentration-dependent manner, both with and without metabolic activating enzymes, and increased the incidence of micronuclei in imprinted control region mouse reticulocytes. Results from three studied constituents of PD, such as podophyllotoxin, kampferol, and quercetin, suggested that the mutagenic effect of PD was not due to the presence of podophyllotoxin, kampferol, and quercetin and might be related to other components and the formation of reactive oxygen species. The detailed mutagenic mechanisms need further investigation, and the medicinal use of PD needs to be cautioned against.     

蚓激酶的诱变实验研究

用鼠伤寒沙门氏菌回复突变试验，小鼠骨髓红细胞微核试验及ＣＨＬ细胞染色体畸变试验，对蚓激酶进行了诱变性试验研究。结果表明鼠伤寒沙门氏菌回复突变试验为阴性，该药可能不诱发基因突变；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、体外遗传物质损伤作用。     

Detection of genotoxicity and mutagenicity of chlorthiophos using micronucleus,chromosome aberration,sister chromatid exchange,and Ames tests

Potential mutagenic and genotoxic effects of Chlorthiophos, an organophosphate pesticide, were evaluated using four standard assays. Five different concentrations of the pesticide were tested by an Ames test using Salmonella typhimurium strains TA97, TA98, TA100, and TA102, with and without S9 metabolic activation. No concentrations of Chlorthiophos showed mutagenic activity on the TA97, TA100, and TA102 strains, with and without S9 fraction, but were all mutagenic to the TA98 strain without S9. Sister chromatid exchange (SCE), chromosome aberration (CA), and micronucleus (MN) tests were used to investigate the genotoxic effects of Chlorthiophos in human peripheral lymphocytes treated with 25, 50, 100, and 200 µg/mL concentrations of Chlorthiophos for 24 and 48 h. The nuclear division index (NDI), replication index (RI), and mitotic index (MI) were also calculated to determine the cytotoxicity of Chlorthiophos. No increase in SCE frequency was seen for any treatment period or concentration, but Chlorthiophos at 200 µg/mL increased the frequency of CAs. Increases in MN formation were only observed at Chlorthiophos concentrations of 200 µg/mL following 24 and 48 h treatments. Chlorthiophos treatment reduced the MI and NDI significantly, but had no effect on the RI. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 937–945, 2015.     

妊高征母血、脐血染色体稳定性和内皮素变化的研究

目的 在致妊高征(PIH)众多因素中,观察PIH孕妇外用血及其脐血姐妹染色单体互换(SCE)频率和内皮素(ET)的变化及其两者的关系,以资探讨PIH的病因和提高PIH的监测水平。方法 采用SCE法和放免法分别对21例PIH病人和15例正常孕妇(对照组)的外周血及其所分娩新生儿脐血SCE频率及其ET进行测定。结果 PIH组外周血和脐血SCE频率分别为6.11±1.29,5.98±1.38;对照组外周血和脐血SCE频率分别为3.45±O.71,3.16±0.57,其两组比较,差异有极显著性(P<0.001)。PIH组外用血和脐血SCE频率皆异常。PIH组外用血ET含量的均值(51.87±24.72pg/ml)明显低于其脐血的均值(63.65±27.63pg/ml),两者比较差异有显著性(P<0.05)。两组SCE和ET相关性分析无明显相关性(r=0.092,P>0.05)。结论 PIH与遗传物质DNA损伤有关,SCE频率可作为一项诊断、预测PIH的重要指标。PIH孕妇脐血ET增高有助于PIH发病机理的揭示。     

Mutagenicity testing with Salmonella microsome test

This in vitro mutagenicity test system comprises five different strains of S. typhimurium as target cells with the rat liver S-9 fraction and appropriate co-factors for metabolic activation of the chemical tested. The bacterial tester strains detect both mutations induced by base pair substitutions and intercalation (frame shift mutations). Usually 10⁸–10⁹ cells of an overnight culture or an exponentially growing culture are incubated for 2–3 days with a mixture of S-9, co-factors, soft agar and the chemical on histidine-deficient agar. The S-9 fraction is obtained from the livers of rats pretreated with 500 mg/kg chlorinated biphenyls (Clophen A-50, Aroclor 1254) to obtain high metabolic activity. For reproducibility it is essential to standardize metabolic activity and protein content of the S-9 and to use three different concentrations thereof in the test system. Since solvents inhibit metabolic activation of the chemicals they must not exceed 4% of the final 2.6 ml incubate.Several independent studies have shown that between 85 and 93% of chemical carcinogens are mutagens in the test. Regarding extrapolation to man one has to consider that the test is preferentially adapted for metabolic activation of the chemicals, whereas inactivation processes are absent or are less active than in vivo. Thus, the test provides qualitative rather than quantitative information on mutagenic effects of a chemical.     

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。     

Biomarkers of environmental contaminants in field population of green mussel (Perna viridis) from Karnataka–Kerala coast (South West coast of India)

The green mussel Perna viridis was sampled from relatively clean and contaminated sites along the Kartanata–Kerala coast (south west coast of India) to study the tissue concentration of trace metals and biological responses to stress (biomarkers) such as sister chromatid exchange (SCE), chromosomal aberration, micronucleus (MN) test, hemic neoplasia (HN), Chromotest (Ames test) and comet assay. In general, mean tissue concentrations of toxic trace metals collected from 25 sampling sites were found to be below the World Health Organisation (WHO) permissible concentration given for seafood. The digestive gland extract of mussels from all 25 sampling sites showed negative reaction for mutagenic activity (Ames test) in the absence of metabolic activation. Very low levels of chromosomal aberration, SCE, MN, HN and comet cells were observed in mussels collected from both the urban associated and relatively clean sites. This study seems to indicate that that the coastal waters of Karnataka and Kerala are minimally contaminated with genotoxic and carcinogenic chemicals.Special Issue on Biomarkers of Marine Pollution and Bioremediation     

荷人脑瘤裸小鼠模型(NHG-1)的活体骨髓细胞 SCE 及染色体畸变分析

采用改良的Perdo方法测定人脑恶性胶质瘤裸小鼠模型(NHG-1)和NC 系正常裸小鼠活体骨髓细胞的SCE,结果提示NHG-1的SCE 值(2.47±0.15)显著高于正常鼠(1.78±0.14)。NHG-1和NC 系正常裸小鼠活体骨髓细胞染色体畸变测定,结果形态异常与正常鼠相近,而染色体计数异常(18.5±44)显著高于NC 系正常鼠(5.4±2.5)。说明SCE 及染色体计数异常频率增高,是NHG-1的重要染色体特征;并为人脑恶性胶质瘤的细胞遗传学研究积累了资料。     

联苯醛酮的致突性与致畸性研究

联苯醛酮为一具有抗病毒活性的化合物。我们观察它的三种短期致突试验及大鼠致畸胎实验。Ames 试验、小鼠骨髓微核试验及中国仓鼠肺细胞的染色体畸变试验均为阳性。但未见大鼠的胚胎毒性及致畸作用。     

国产环丙沙星的诱变性和致癌性研究

应用小鼠骨髓细胞微核试验、CHL细胞染色体畸变试验及叙利亚地鼠胚胎细胞转化试验,对国产环丙沙星进行了诱变性和致癌研究。结果: 环丙沙星在小鼠骨髓细胞微核试验和CHL细胞染色体畸变试验中均为阴性;在细胞转化试验中不诱发SHE细胞发生形态转化。实验结果提示环丙沙星在体内、外不引起染色体损伤;无体外致癌作用。     

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.