Antigenotoxic effect of allicin against methyl methanesulphonate induced genotoxic damage

Allicin, one of the sulfur compounds especially thiosulphonates of garlic (Allium sativum), possesses antioxidant and thioldisulphide exchange activity and is also shown to cause a variety of actions potentially useful for human health. In this investigation we determined its antigenotoxic potential using chromosomal aberrations (CAs) and sister chromatid exchanges (SCEs) induced by methyl methanesulphonate (MMS) as genotoxic end points both in the presence as well as absence of rat liver microsomal activation system (S9 mix) in cultured human lymphocytes. We tested the effect of 5, 10 and 20 microM of allicin on the damage exerted by 60 microM of MMS. The levels of CAs and SCEs were lowered suggesting an antigenotoxic role of allicin against genotoxic damage both in the presence as well as absence of metabolic activation.     

Effect of caffeine, norfloxacin and nimesulide on heartbeat and VEGF expression of zebrafish larvae

The use of pharmaceuticals during pregnancy may causes abnormalities to the embryo. Sometime the drug also effect to the new born if the drug transferred through lactation. We have used zebrafish model to see the effect of some pharmaceuticals on embryos and larvae. Three drugs, caffeine, norfloxacin and nimesulide, were used for this study to see the effect mainly the hatching rate of eggs, heart beat rate and the vascular endothelial growth factor (VEGF) expression of the larvae. VEGF is an important signaling protein that involved generating the new blood vessels during embryonic development. We have used 10, 20, 50, 100 microg ml(-1) concentrations of all the drugs to see the effect. No significant mortality or malformations were observed in zebrafish embryos. Hatching was stared from 60 hr. In control group, 91% hatching rate was observed. Lowest hatching rate was observed using highest concentration of norfloxacin (100 microg ml(-1)) and nimesulide (100 microg ml(-1)) i.e. 55 and 56% respectively. In control group, 110 to 115 heart beat rate was counted per minute. Significantly higher heart beat was observed in caffeine treated group which is 125 to 140 min(-1) Lower heart beat was noted in nimesulide treated group which is 100 min(-1). We have tried to observe the possible effect of VEGF of the larvae by these three drugs. Expression of VEGF was very low in caffeine treated group. Almost no VGF expression was observe in 100 microg ml(-1) caffeine treated group. These studies suggest that there is a possibility that high dosage of caffeine can harm the unborn baby or new born babies, if the mothers use caffeine.     

In vitro Screening von Pflanzenschutzmittel-Wirkstoffen auf östrogene Aktivität

Over the last years, the obviously increasing, hormone-dependent impairments observed in humans and animals, as well as the increased occurrence of hormone-dependent types of cancer, are sometimes associated with environmental chemicals which are suspected to imitate or block the effects of natural hormones. For a variety of environmental chemicals an endocrine efficacy could already be demonstrated. Little is known, however, about a possible hormonal activity of plant protection agents which are at present certificated in the Federal Republic of Germany. The aim of the present study was the in vitro testing of at least 57 active ingredients of pesticides and growth regulators certificated in the Federal Republic of Germany, for their possible estrogenic activity. The E-Screen-Assay based on the human breast cancer cell line MCF-7 was used as the suitable test system. For at least 8 of the tested substances, an receptor-mediated estrogenic activity could be shown in vitro. With the exception of one substance, 7 active ingredients displayed a very weak affinity for the human estrogen receptor. Their ability to displace 17β-estradiol from the receptor was low. Only the herbicide Pendimethalin is to be classified as a full estrogen receptor agonist; it is able to displace 17β-estradiol almost completely from the receptor. Howeverm the estrogenic potency of Pendimethalin, in comparison to 17β-estradiol, was seen to be as small as the estrogenic potency of the other 7 substances tested positively in the E-Screen-Assay. Among this 7 substances, two could not be classified as estrogenically active anymore, because their affinity to the human estrogen receptor was too weak. The relevance of the available results for livng organisms should be clarified in further in vivo investigations.     

长江中下游环境激素效应的污染特征及生态风险

生活污水和养殖废水排放导致受纳水环境中激素类物质的污染,对水生生物产生不利影响。分别利用嵌入雌激素受体和雄激素受体的基因重组酵母菌测定了长江中下游流域不同时期水体和沉积物中4种环境激素效应,即雌激素效应、抗雌激素效应、雄激素效应和抗雄激素效应。结果表明,雌激素效应污染最为普遍,在地表水和沉积物中检出率均超过50%,水体和沉积物的最高浓度分别为2.05 ng·L~(-1)雌二醇当量(EEQ)和0.43 ng EEQ·g~(-1)。其他3种激素效应在水体和沉积物介质中的检出率均低于雌激素效应,按总体检出率来看:抗雄激素效应雄激素效应抗雌激素效应,3种激素效应在水体中最大检出浓度分别为144μg·L~(-1)氟他胺当量(FEQ)、37.9 ng·L~(-1)二氢睾酮当量(DEQ)和103μg·L~(-1)他莫西芬当量(TEQ),在沉积物中分别为53.6μg FEQ·g~(-1)、12.0 ng DEQ·g-1和51.5μg TEQ·g~(-1)。环境激素效应的浓度分布在水体中均呈现季节性的差异,雌激素效应的区域性高值位于武汉段、鄱阳湖口和芜湖-南京段,其他3种激素效应没有明显的高污染区域。环境激素效应与当地人口数量、有机质、氨氮等呈现一定相关性,表明环境激素效应与人类活动排放密切相关。雌激素效应仅在鄱阳湖口点位具有高风险,其他区域为中等风险,雄激素效应无高风险区域。研究结果有助于认识长江中下游区域的环境激素效应污染态势,为相关污染控制提供基础数据。     

Effects of benzo(k)fluoranthene,a polycyclic aromatic hydrocarbon on DNA damage,lipid peroxidation and oxidative stress in marine gastropod Morula granulata

Benzo(k)fluoranthene [B(k)F] is one of the widespread priority pollutants of polycyclic aromatic hydrocarbons that has been scarcely studied for exposure assessment. With studies reporting a high amount B(k)F in sediments and water samples around the world, it has become vital to study its effects on aquatic organisms. In this connection, this study is conducted to study the effect of different concentrations of B(k)F (1, 10, 25 and 50?µg/L) in marine gastropod Morula granulata exposed in vivo for 96?h. A concentration-dependent increase in percentage tail DNA (TDNA) as measured by comet assay was observed in snails exposed to B(k)F. Exposure concentrations above 1?µg/L B(k)F showed significant increase in superoxide dismutase (SOD) activity and lipid peroxidation value in snails. After 96?h, SOD activity was found to be doubled for 50?µg/L B(k)F in comparison to control. A significant increase in catalase and glutathione S-transferase activity was observed at all exposure conditions at the end of the exposure time. Our study showed that B(k)F induces oxidative stress in snails which further lead to genotoxic damage. To our knowledge, this is the first study on oxidative stress and genotoxic damage in gastropods exposed to B(k)F.     

Östrogene Wirkung von Xenobiotika

A number of xenobiotic organic substances are known which, in cases of prenatal exposition, may produce an estrogenic effect leading subsequently to serious reproductive disorders in the male progeny. Damage of this kind which is seen to occur in wildlife populations leads to the assumption that environmental chemicals exerting such estrogenic effects may be responsible for these disorders. Listed here are environmental chemicals which are known to date to exert an estrogenic effect. The article provides a review of papers and hypotheses on the estrogenic effects of xenobiotic substances. This is followed by a discussion concerning the significance of chemical estrogenicity on environmental and chemical policies as well as on the possibilities and limitations of test systems for the verification of estrogenicity.     

Antimutagenic and/or genotoxic effects of processed humic acids as tested upon S. cerevisiae D7

Humic acids (HAs) are formed during decomposition of organic matter. Their adsorption, dispersion or emulsification properties attract the interest of medical science and pharmacy. The aim of this work was to study antimutagenic effects of processed HA. Yeast strain Saccharomyces cerevisiae D7 was first used for HA antimutagenicity testing. The highest antimutagenic activity was found in potassium and sodium humates. Humates isolated from lignite pre-treated by HNO₃ exhibited slightly lower antimutagenic activity; this effect is caused probably by their higher oxidation degree. Sodium humate processed at 250°C exhibited genotoxic effect, which is probably connected with accelerated formation of reactive oxygen species such as superoxide anion by HA at higher temperature.     

An anticlastogenic in vivo micronucleus assay for tea

Common use of antimutagens and anticarcinogens in everyday life is an effective measure for preventing human cancer and genetic diseases. Antioxidant properties of tea have vast potential as protective agents against diverse toxic effects. The present study was aimed to evaluate the role of aqueous clonal tea extracts (green tea, oolong tea and black tea) in modulating the genotoxic damage induced by cyclophosphamide (CP), a commonly used chemotherapeutic drug and a well-known mutagen and clastogen. All the three tea extracts at 1 and 2% concentration did not increase the frequency of micronucleated polychromatic erythrocytes (MPE) in bone marrow cells of mice when administered individually. The tea extracts decreased the micronuclei (MN) induced by CP. Therefore, regular intake of tea may improve the antioxidant status in in vivo and thereby reduce the risk of cancer and coronary heart disease.     

Genotoxicity assessment of human peripheral Lymphocytes induced by thallium(I) and thallium(III)

Thallium is a non-essential metal with a wide range of industrial uses. However, thallium is also a potential pollutant with high potential toxicity to humans. In the present study, we analyzed and compared the cellular and genotoxic effects of thallium in two main oxidation states by applying chromosome aberration assays to human peripheral lymphocytes. We observed that thallium(I) sulfate reduced the mitotic index at all tested concentrations (0.5, 1, 5, 50 and 100 μg/mL), whereas thallium(III) chloride was toxic at concentrations ≥1 μg/mL. Thallium(I) and thallium(III) treatment significantly increased structural chromosomal aberrations, with and without gaps, and increased the percentage of aberrant cells without gaps. Furthermore, satellite associations and numerical chromosomal aberration tests showed significant differences at a few of the tested concentrations. The satellite association test is related to aneuploidy. Thallium salts increased satellite associations when hyperploid cells were observed. Our results indicated that the two oxidation states of thallium induced toxicity in vitro – i.e. cyto/genotoxic (clastogenic and aneuploidogenic) effects.     

Characterization and in vitro biological effects of ambient air PM10 from a rural,an industrial and an urban site in Sulaimani City,Iraq

Abstract

High urban atmospheric pollution is caused by economic and industrial growth, especially in developing countries. The objective of this study was to assess possible relationships between in vitro effects on human alveolar epithelial cells of source-related dust types collected at Sulaimani City (Iraq), and to determine their mineralogical and chemical composition. A passive sampler was used to collect dust particles at a rural, an industrial and an urban sampling site during July and August 2014. The samples were size-fractionated by a low-pressure impactor to obtain respirable dust with aerodynamic diameters of less than 10?µm. The dust was mainly composed of quartz and calcite. Chrysotile fibers (white asbestos) were also found at the urban site. Dust from the industrial and urban sites triggered cytotoxic and genotoxic effects in the cells, whereas only minor effects were observed for the sample from the rural site.     

Tetracycline antibiotics in the environment: a review

Tetracycline antibiotics are one of the primarily antibiotics groups used for veterinary purposes, for human therapy and for agricultural purposes. Amongst the different antibiotics used, more attention is paid to tetracycline’s as it exhibits serious environmental problems including ecological risks and human health damages. Due to their extensive usage, most of the actual evidence suggests that tetracycline antibiotics are omnipresent compounds found in different ecological compartments. After medication, more than 70 % of tetracycline antibiotics are excreted and released in active form into the environment via urine and feces from humans and animals. Their highly hydrophilic character and low volatility have resulted in significant persistence in the aquatic environment. Very few studies describe the fate and toxicity of tetracycline antibiotics in the environment. Here, we review several important issues with regard to: (1) the toxicity of these compounds on aquatic and terrestrial organisms; (2) their estrogenic effects; (3) their behavior in different ecological systems and; (4) the by-products generated during water treatment. These antibiotics residues promote the development of antibiotic resistant microorganisms, which can induce adverse effect to human health by increasing the risk of certain infections. Based on recent research results, the occurrence of tetracycline antibiotics in the environment inhibits the growth of some terrestrial and aquatic species. Besides, the residual concentrations of such drugs could affect steroidogenic pathway and consequently may cause endocrine disruption of aquatic species. Most of the wastewater treatment plants are not capable of removing effectively the tetracycline antibiotics. Therefore, there is a need to develop alternative processes to remove them from waters. Advanced oxidation processes have been proposed as alternative methods to ensure higher degradation and mineralization of tetracycline antibiotics are present in waters.     

沿海三市饮用水源水内分泌干扰毒性研究

近十多年来,江苏沿海化工产业发展迅速,化工废水的长期排放对水生生态系统及人群健康构成潜在威胁.采用非洲猴肾细胞(CV-1)核受体介导的体外转录激活试验方法,对中国东部沿海A、B、C三市的6个水源地进行了拟雌激素活性调查研究.结果表明:C市2处水源水的有机提取物在枯水期、平水期和丰水期均无拟雌激素活性检出,水质较好;A市...     

Cytogenetic evaluation of Fansidar on human lymphocyte chromosomes in vitro

Fansidar is a fixed combination of two antimalarial agents a diaminopyrimidine (Pyrimethamine) and a sulphonamide (Sulphadoxine) in the ratio 1:20- that have been used extensively worldwide for the treatment of Chloroquine resistant Plasmodium falciparum malaria, toxoplasmosis and Pneumocystis carinii pneumonia in patients with the acquired immunodeficiency syndrome. This study examined the effect of Fansidar on chromosomes in human lymphocyte culture. Fansidar was added to peripheral blood lymphocyte cultures in vitro at four different concentrations: 5,15, 25 and 50 microl in the ratio 1:20, 3:60, 5:100 and 10:200 microg ml(-1). Result shows that this drug induces moderate increase in the frequency of gaps, breaks and rearrangements. Therefore it can be concluded that Fansidar has moderate clastogenic effect on human chromosomes in vitro.     

Protective effects of vitamin C and curcumin against acrylamide toxicity in embryonic fibroblast cells

Abstract

Acrylamide is a highly soluble and widely produced industrial chemical that has been shown to pose numerous health hazards. This study aimed to assess the effects of acrylamide on the cytotoxicity and oxidative damage in embryonic fibroblast cells (BALB/c 3T3) and to measure protective roles of the natural antioxidants vitamin C and curcumin. Embryonic fibroblast cells were exposed to acrylamide at concentrations of 1, 10, 100, and 1000?μmol/L and vitamin C (50?μmol/L) or curcumin (2.5?μmol/L) for 24?h. Cell viability, cytotoxicity, the activities of antioxidant enzymes superoxide dismutase, glutathione-S-transferase, glutathione peroxidase and catalase, and the markers of oxidative lipid peroxidation, hydroxyl radical, hydrogen peroxide and glutathione were measured. Co-treatment of the acrylamide-exposed fibroblast cells with vitamin C or curcumin attenuated the cytotoxicity and formation of reactive oxygen species and decreased the antioxidant enzyme activity. Thus, it was concluded that vitamin C and curcumin may play a protective role against acrylamide toxicity; the treatment with 50?μmol/L vitamin C was found to be more effective than the treatment with 2.5?μmol/L curcumin.     

Ecotoxicological investigations of extremely acidic mining lakes using bioassays suitable for testing at low pH

In this investigation different bioassays were used to detect the physiological and genotoxic effects of water samples of mining lakes. Especially bioassays with higher plants were used like the duckweed bioassay with Lemna minor, the cress bioassay with Lepidium sativum, the Tradescantia‐micronucleus bioassay and the Arabidopsis bioassay. In addition the algae‐motility bioassay with Euglena gracilis were used. All these bioassays were found to be suitable to investigate mining lake samples of extreme acidic character. Four mining lakes (ML 107, ML 111, ML 117, ML F) were selected. They show equally low pH‐values, but differ in size, age, hydro‐chemical and biological state. The results demonstrated that it is possible to differentiate the mining lakes based on the results of bioassays. Samples of ML 107 and 111 showed significant physiological and genotoxic effects. Water samples of both lakes caused severe damages and decreased growth at the same dilution level in all plant bioassays. ML F causes different effects on bioassays. The highest negative effect was observed on root development of L. sativum. ML 117 did not show any effects on duckweed, algae, Tradescantia or Arabidopsis bioassays. There was only a slight effect on the root development in the cress bioassay.     

Genotoxicity and mutagenicity of electronic waste leachates using animal bioassays

Human exposure to electronic waste (e-waste) is increasing, especially in developing nations. This has potential short and chronic adverse health risks. Information is currently scarce on potential genotoxicity of e-waste leachate. In this study, the potential mutagenic and genotoxic effects of leachates from e-waste dumpsites at two electronic markets in Lagos, Nigeria, were investigated. The assays utilized were: bone marrow micronucleus (MN) and chromosome aberration (CA), spermatogonia CA, sperm morphology, and sperm count in mice. Experiments were carried out at concentrations of 1%, 5%, 10%, 25%, and 50% (v/v; leachate: distilled water) of leachate samples. MN analysis showed a concentration-dependent induction of micronucleated polychromatic erythrocytes (MNPCE) across the treatment groups. In the CA tests (bone marrow and spermatogonia), there was concentration-dependent significant reduction in mitotic index and induction of different types of CA. Assessment of sperm shape showed a significant increase in sperm abnormalities with significant decrease in mean sperm count in treated groups. Heavy metals analyzed in the tested samples are believed to contribute significantly to the observed genetic damage. This indicates that e-waste contains potential genotoxic agents; and constitutes a genetic risk in exposed human population.     

构建有机化合物斑马鱼雌激素干扰效应的二元分类模型

计算毒理学方法已成为辅助内分泌干扰物(EDCs)管理的决策支持工具。因此,发展内分泌干扰效应指标的(定量)结构活性关系((Q) SAR)等预测模型对于实现EDCs环境管理具有重要的意义。在雌激素受体(Q) SAR模型研究方面,目前主要针对人、牛、大鼠和小鼠等物种的雌激素受体干扰效应进行了研究,而对鱼等水生生物雌激素受体干扰效应等指标的(Q)SAR模型研究还较少。本研究采用基于欧几里德距离的K最近邻(k NN)分类算法,构建了斑马鱼雌激素受体干扰效应的二元分类模型。结果表明,2个最优模型训练集和验证集的预测准确度(Q)、敏感性(Sn)和特异性(Sp)参数均大于0.93,说明模型具有较好的预测能力。因此,能够用所建模型填补模型应用域内其他化合物缺失的斑马鱼雌激素受体干扰效应定性数据。     

The roach (Rutilus rutilus) as a sentinel for assessing endocrine disruption.

Alterations in development and reproduction as a consequence of exposure to endocrine-disrupting chemicals (EDCs) have been demonstrated in many wildlife species. Animals living in, or closely associated with, the aquatic environment are particularly vulnerable to endocrine disruption because thousands of chemicals are actively disposed into rivers, estuaries and seas. Fish have thus been a focus in endocrine disruption studies, and some of the most comprehensive studies on the disruption of sexual development and function are on the roach (Rutilus rutilus). This paper provides a critical analysis of the roach as a sentinel for studies into endocrine disruption. The paper starts by describing what is known on the basic reproductive biology of the roach, information essential for interpreting chemical effect measures on sexual development and function. We then analyze where and how the roach has been applied to improve our understanding of the estrogenic nature of discharges from wastewater treatment works (WWTWs) and describe the phenomenon of feminized male roach in UK rivers. In this paper, the causation of these effects and issues of relative susceptibility and sensitivity of the roach to the effects of estrogenic EDCs are addressed. The paper then describes the ongoing work on the development of genetic and genomic resources for roach and analyses how these are being applied in studies to understand the mechanisms of disruption of sexual development. Finally, the paper addresses the biological significance of sexual disruption and intersex for the individual and discusses the possible implications for wild populations.     

Genotoxic effects of Ag2S and CdS nanoparticles in blue mussel (Mytilus edulis) haemocytes

The use of functionalised metal sulphide nanoparticles (NPs) for nanoremediation and biomedical application is rapidly increasing, which could lead to significant inputs into the marine environment. The potential impact of some NPs on marine organisms is still poorly understood. In the present paper the genotoxic potential of Ag₂S and CdS NPs on Mytilus edulis haemocytes was assessed. MPEG-SH (thiol-terminated methyl polyethylene glycol), was used as capping agent to avoid NPs agglomeration. TEM analysis showed that the Ag₂S NPs size was 13±7 nm, whereas CdS quantum dots had an average diameter of 4±1 nm. DNA integrity was evaluated by Comet assay following exposure to increasing concentration series (0.01–10 mg/L). Both silver and cadmium NPs showed genotoxic effects at the highest dose. MPEG-SH was also found to exert a weak genotoxic activity, suggesting that at least part of the genotoxic potential of functionalised NPs on mussel cells might be attributable to the capping agent. These results confirm the genotoxic potential of Ag₂S NPs for mussel cells and demonstrated, for the first time, that CdS NPs is genotoxic in a marine organism.     

Medaka (Oryzias latipes) for use in evaluating developmental effects of endocrine active chemicals with special reference to gonadal intersex (testis-ova).

Japanese medaka (Oryzias latipes) has been widely used for the evaluation of the toxicity of endocrine active chemicals (EACs) and other chemicals as well as for monitoring the adverse effects of effluent discharges in relation to sexual development and function. It is useful for these evaluations for many reasons including the following: 1) it has a short life cycle facilitating studies extending over long phases of development and over multigenerations, 2) it is easy to rear, 3) male and female phenotypes can easily be distinguished on the basis of secondary sex characteristics, and 4) a genetic marker (DMY) is available for identifying the true genotypic sex. Several biomarkers have been found to be useful for identifying the effects of exposure to estrogenic and androgenic chemicals in medaka and they include increased levels of hepatic vitellogenin (VTG) and testis-ova induction in males for exposure to estrogenic chemicals, and decreased levels of hepatic VTG in females and an altered morphology of dorsal and anal fins and formation of papillae for androgenic chemicals. In this paper, we present a critical analysis of the use of medaka as a test species for studies of endocrine disruption and report on the use of sex-related genetic markers and alterations in gonadal development, including the induction of testis-ova formation, for assessing the disruptive effects of EACs. In this paper, we focus on some of the more recent studies and findings.