Day 1 :
- Workshop
Location: Hall 5
Session Introduction
Susana Garcia de Arriba
Schaper & Brümmer GmbH & Co. KG., Germany
Title: Human safety of free Hydroquinone derived from herbal medicinal products containing Uvaeursi folium
Time : 09:55- 10:55
Biography:
Susana Garcia de Arriba studied Pharmacy at the University of Valencia, Spanien. Her M.Sc. in Pharmaceutical Science completed at the Faculty of Pharmacy, University of Gent, Belgium. She completed her PhD in Pharmacology at the University of Leipzig (Germany). She worked as postdoctoral fellow at the Rudolf- Boehm Institute of Pharmacology and Toxicology as well as at the Interdisciplinary Center for Clinical Research (IZKF), Neuro-immunological Cell Biology Unit, University of Leipzig. Since July 2008 works for the company Schaper & Brümmer as Scientific & Medical Expert inside of the department of Regulatory Affairs in Salzgitter Ringelheim, Germany. Her areas of expertise are Herbal Medicinal Products, Phytotherapy, processes of Aging, Neurodegeneration, mechanism of drug action and mechanism of drug toxicity.
Abstract:
Uvae ursi folium (bearberry leaf) has been traditionally used to treat symptoms of lower urinary tract infections. Arbutin, the major active constituent, is rapidly absorbed in the small intestine and undergoes hepatic conjugation to form hydroquinone (HQ) conjugates. Because arbutin is broken down to yield free HQ, concerns regarding the safety of free HQ have raised serious questions about the safety of herbal preparations containing extracts of Uvae ursifolium. Data on pharmacokinetics in humans helped to estimate human exposure to free HQ: 11 μg/kg body weight /day in urine after the therapeutic daily dose of 420 mg arbutin. The permitted daily exposure of free HQ in humans was estimated at 100 μg/kg body weight/day. Dietary sources of arbutin/HQ generate comparable free HQ exposure levels as therapeutic doses of Uvae ursifolium. No direct evidence has been found supporting the toxicity of free HQ derived from herbal medicinal products. On the other hand, the mutagenic potential of free HQ derived from a therapeutic dose of Uvae ursifolium extract (1,6 g Uvae ursifolium extract corresponding to 420 mg arbutin) was investigated in urine samples of healthy volunteers (n=12). Free and total HQ were firstly estimated in single urine samples. Both, the in vitro AMES assay and the in vivo micronucleus assay were negative for mutagenicity activity. Therefore, urine samples obtained from healthy volunteers receiving an Uvaursi folium extract at the same dose as proposed for therapeutic use bears no mutagenic risk.
- Track 1: Predictive Human Toxicity and ADME/Tox Studies
Track 2: Adverse Outcome Pathways
Track 3: Environmental Toxicogenomics
Location: Hall 5
Chair
Susana Garcia de Arriba
Schaper & Brümmer GmbH & Co. KG., Germany
Session Introduction
Catherine Willett
The Humane Society of the United States, USA
Title: Adverse Outcome Pathways in Predictive Toxicology
Time : 11:15-11:45
Biography:
Catherine Willett obtained her PhD in Genetics at the University of California, Davis, followed by a postdoc in developmental biology at the Massachusetts Institute of Technology. After serving as principle investigator on several projects for a biotech startup company, for the past 9 years she has focused on non-animal approaches to assessing chemical safety. She is currently the Director of regulatory toxicology, risk assessment and alternatives at the Humane Society of the United States. She has authored more than 25 peer reviewed publications and is on the scientific advisory boards of several organizations.
Abstract:
Chemical risk assessment involves the weighing of diverse sources of information within specific decision contexts to reach conclusions about the safety or risk of unsafe exposure. Adverse Outcome Pathways (AOPs) offer a systems biology-based toxicological framework to support hazard and risk assessment and reduce uncertainty in regulatory decision-making. All information relating to what is known about a specific biological process, from the molecular initiating event through cellular-, tissue-, organ-, organism- and population-level events, to a resulting adverse outcome are collected and evaluated. This framework can be used to support and improve multiple different kinds of chemical assessment processes, from chemical categorization and read across, the design of Integrated Assessment and Testing Approaches (IATA), to predicting the likelihood of an adverse outcome based on mechanistic information. The utility of a pathway to support hazard and risk decisions is directly related to the amount and quality of information informing that pathway; nevertheless, even relatively sparsely informed pathways can be useful to support many types of decisions. The US EPA, European Commission and the Organization for Economic Cooperation and Development have jointly created templates, guidance and databases to support the development and assessment of AOPs. The success of pathway-based approaches depends on global cooperation to develop AOPs and strong international cooperation to implement them in safety decisions.
Jenny Bosson
Umea University, Sweden
Title: Cardiovascular and respiratory effects of RME biodiesel exhaust exposure
Time : 11:45-12:15
Biography:
Jenny Bosson completed her Bachelor of Science at Roanoke College, VA, USA and then went on to complete her MD and PhD at Umea University School of Medicine, Sweden. She is currently a physician and senior researcher at the Department of Medicine, Division of Respiratory Medicine and Allergy at University Hospital in Umea, Sweden. She has published over 15 papers in reputed journals and is a supervisor to several PhD and medical students conducting research within health effects of air pollution as well as e-cigarettes and tobacco.
Abstract:
Air pollution is a global environmental and health concern, contributing to onset and deterioration of respiratory and cardiovascular diseases. As climate change and dependence on diminishing fossil fuel supplies have taken center stage in political and scientific debates, renewable CO2-neutral fuels like biodiesel receive increasing attention. The most common biodiesel within the EU, RME (rapeseed oil methyl ester), has been shown to emit fewer exhaust particles compared to standard petro diesel and this perceived “green fuel”, being sustainable and of biological origin, is often predicted to be less harmful to human health. Whilst replacing petro diesel with biodiesel may have advantageous ecological impacts, consequences to public health remained unexplored. In three separate studies, healthy volunteers were exposed to filtered air, petro diesel or biodiesel exhaust for one hour in a controlled chamber. Following exposure in study one and two, cardiovascular endpoints were assessed. In study three, bronchoscopy was performed six hours following completion of exposure. Compared to petro diesel, RME exhaust contained less elemental carbon, fewer poly aromatic hydrocarbons, lower levels of hydrocarbons and higher concentration of nitrogen oxides. RME showed a shift in the particulate matter size distribution towards the ultrafine range and a significantly increased concentration of a range of metals relative to petro diesel. These studies demonstrate that RME exhaust exposure results in comparable adverse respiratory and cardiovascular effects to petro diesel exhaust despite varying composition and particle reactivity. We would recommend that adverse health effects be addressed alongside environmental concerns when new fuel policies are considered due to potential major public health impacts.
Wilhelm Gaus
University of Ulm, Germany
Title: Explorative versus Confirmative Interpretation of Statistical Significance in Toxicological Research using Ginkgo biloba as an Example
Time : 12:15-12:45
Biography:
Wilhelm Gaus, PhD was head of the department of Medical Documentation and Biometry of the Medical Faculty of the University Ulm, Germany for more than three decades. In 2004 he retired but is still active. Totally he published about 250 papers. He was especially active in proving efficacy and safety of herbal medicines. In 2014 he published a textbook on Medical Statistics.
Abstract:
Some people present a statistical significance like a trophy. It is possible that no other statistical result is misinterpreted as often as the p-value. The two most important rules for a decent interpretation of p-values are: (1) “Never interpret a p-value without the appropriate descriptive statistic.” and (2) “Distinguish between explorative and confirmative testing.” This presentation deals with the latter. There are two steps to experimental research: hypothesis generation and hypothesis confirmation. A p-value can therefore be explorative, i.e. it produces a new hypothesis or it is confirmative, i.e. it provides “statistical proof.” The distinction between explorative and confirmative statistics is not linked to the type of the outcome variable (qualitative or quantitative), the number of groups (1, 2 or more groups), the design of the study (parallel groups or cross-over settings), nor to the statistical test applied (chi-square test, Wilcoxon test, analysis of variance, etc.). In order to allow for a confirmative interpretation of p-values, two prerequisites must be fulfilled: Firstly, a precise hypothesis has to be established beforehand independent from the data now used for the statistical test at that point. Secondly, only one single statistical test has been computed or the p-values have been adjusted for multiple testing. Let us do an experiment in our minds in order to understand the meaning of the p-value. Let us assume that we have data coming from a random number generator – in modern times this is not a dice but by a computer program – and that there is definitely no effect. Here, the probability to obtain a false significant result is the p-value. If 300 tests are done with random numbers, for example, each of them with a level of significance of 5%, then we expect 300  0.05 = 15 false significant results. A reasonable scientist will not compute all of these 300 tests. If he can deduct from the means or the frequencies that there is no chance of a significant result, he will save unnecessary work. But formally, all of these 300 tests are done. The purpose of toxicological screening programs is to identify all kinds of interesting things within the considered field. Therefore, they are explorative. The words “to screen” and “to explore” already have a similar meaning. Let us now look at the US National Toxicology Program’s Technical Report TR 578 on Ginkgo biloba as an example. In this report, a 3-month study on rats, a 3-month study on mice, a 2-year study on rats, and a 2-year study on mice are being reported. In this investigation, around 1000 statistical tests are possible. If the data stemmed from a random number generator and if a level of significance of 5% was selected, then we expect 1000  5% = 50 false significant results. The number of reported significant findings is roughly the same as the number of expected false significant tests. Gaus (2014) points out that all significant findings in TR 578 are explorative and that they generate new hypotheses. Kissling et al (2014) are more or less involved in the NTP and have rejected it passionately. This is an indication that the distinction of explorative and confirmative testing is important, but not widespread. Furthermore, we recommend to not only look at p-values, but to also consider a wide variety of information sources in a cross-matching approach (Heinonen 2015).
N L Reynaert
Maastricht University Medical Centre, The Netherlands
Title: Insights into pathogenic mechanisms of crystalline silica by profiling the acute response of lung epithelial cells – Focus on inflammasome activation in vitro and in vivo
Time : 13:30-14:00
Biography:
N L Reynaert received her PhD cum laude in 2006 from Maastricht University on research performed in the laboratory of Prof. Janssen-Heininger at the University of Vermont, USA. She received funding from the Dutch Lung Foundation and received a prestigious personal grant from the Dutch Foundation for Scientific Research. She is the recipient of multiple awards from the European Respiratory Society and the Society for Free Radical Biology and Medicine. In 2003 she performed a sponsored fellowship in the laboratory of Prof. Brightling at the University of Leicester, UK. At the Maastricht University Medical Centre she supervises multiple PhD projects on the topics of COPD and silicosis with an emphasis on inflammation, ageing and matrix remodeling. She has published more than 40 papers in reputed journals.
Abstract:
Occupational and environmental exposures to asbestos and silica are associated with the development of lung fibrosis in the forms of asbestosis and silicosis, respectively. However, both diseases display distinct pathologic presentations, likely associated with differences in gene expression induced by different mineral structures, composition and bio-persistent properties. We determined gene expression profiles and performed in-depth pathway analysis to dissect the effects of mineral exposure in the airway epithelium which may dictate early deviating molecular events that may explain the different pathologies of asbestosis versus silicosis. Our findings reveal that both minerals had potent effects on genes governing cell adhesion/migration, inflammation, and cellular stress, key features of fibrosis. Asbestos exposure was specifically associated with aberrant cell proliferation and carcinogenesis, whereas silica exposure was highly associated with additional inflammatory responses, pattern recognition and fibrogenesis. These findings illustrate the use of gene-profiling to determine early molecular events that may dictate pathological processes induced by exogenous cellular insults. A common inflammatory cascade activated in bronchial epithelial cells was the NLRP3-inflammasome. In response to silica this was found to induce secretion of IL1ï¢, the danger molecule HMGB1 and bFGF in a particle uptake-dependent manner, and enhanced fibroblast proliferation in an autocrine fashion. Inflammasome activation furthermore occurred throughout the lungs in a rat model of silicosis, acutely upon intratracheal instillation of DQ12 silica and up to 1 year post exposure. Activation of the inflammasome was found to depend on surface reactivity as PVNO coated DQ12 markedly attenuated inflammasome-dependent readouts in vitro as well as in vivo.
Ezejiofor Tobias I Ndubuisi
Federal University of Technology, Nigeria
Title: Oxidative stress parameters as markers of exposure to toxic organic pollutants among petroleum distribution industry workers in Nigeria
Time : 14:00-14:30
Biography:
Tobias I Ndubuisi Ezejiofor obtained a BSc degree in Medical Laboratory Sciences (Rivers State University of Science & Technology, Port Harcourt), MSc Applied Biochemistry (Nnamdi Azikiwe University, Awka), and PhD Environmental Health Biology (Federal University of Technology, Owerri(FUTO), Nigeria. He is licensed by Environmental Health Officers Registration and Medical Laboratory Science Councils of Nigeria. A member of many professional associations and learned societies, he is a Fellow of the College of Biomedical Engineering and Technology (FCBET), Nigeria. He is a senior Lecturer and heads the Occupational and Environmental Toxicology Research laboratory of the Department of Biotechnology, FUTO, Nigeria. He has published over 25 papers in reputed journals, and serving as reviewer to many such international journals. He had given several conference papers locally and internationally.
Abstract:
Exposures in chemically hostile environments often result in generation of oxidative stress within the body, on account of excessive production of free radicals. The success of the body in dousing the cascade of ill-events associated with the presence of free radicals depends on the availability of equally potent agents that provide counteractive effects to the activities of free radicals. These agents also known as antioxidants give protection to the body by successfully mopping up excess free radicals in the body. Excess of the radicals over that of the body’s antioxidants reserve, as may happen following exposure to toxic organic pollutants in an industrial environment, often favours the establishment of sundry health effects. This study was designed to examine the status of oxidative stress parameters as possible markers of exposure to toxic organic pollutants among petroleum distribution industry workers in Nigeria. Blood sample (5ml) was collected from each of the 50 study participants consisting of 35 oil workers (exposed), and 15 non oil workers (referents). Standard assay methods were adopted for analyses of the parameters of interest. Result of the study showed that for oil workers, Malondialdehyde(MDA),37.9-96.70(59.31±11.90 mg/dl), Vitamin C, 0.35-1.52 (0.78±0.28 mg/dl),Vitamin E, 0.22-0.51(0.31±0.06mg/dl), Reduced glutathione (GSH) ranged 0.2-0.8 with a mean of 0.49±0.20mg/dl; while among the non-oil workers the values were as follows: MDA, 30.3-60.7(49.58±8.12 mg/dl), Vitamin C, 0.41-2.22 (1.26±0.42 mg/dl), Vitamin E, 0.24-1.99(0.44±0.43 mg/dl), GSH, 0.4-1.7 (mean= 0.83±0.32 mg/dl) respectively. A review of the results show that, among the oil workers, the lipid peroxidation substance, MDA was significantly higher (P=0.006) while the antioxidant parameters were significantly lower (p<0.0001), whereas the reverse was the case among the non-oil workers, because MDA was significantly lower in them (P<0.001) even as most of the antioxidant parameters were significantly higher in them. Higher lipid peroxidation substance (MDA) and a dwindling antioxidants status as found among the oil workers gives a clear signal of a higher presence of free radicals that is depleting the antioxidants reserves in the oil workers as compared with the reverse situation among their non-oil work referents, indicating that relative to the referents, the oil workers were most likely to be affected by adverse conditions associated with oxidative stress including a greater tendency to sundry health effects. The results also showed that oxidative stress markers can indeed serve as putative markers of exposure to toxic organic pollutants in the oil and gas industry.
Jurgen Borlak
Hannover Medical School, Germany
Title: A rat toxicogenomics study with the calcium sensitizer EMD82571 reveals a pleiotropic cause of teratogenicity
Biography:
Jurgen Borlak obtained his Doctorate at the University of Reading, GB. In the year 2000 he received the venia legendi in Pharmacology and Toxicology at Hannover Medical School (MHH) and since 2002 was appointed as full Professor and Director of the Institute of Pharmaco- and Toxicogenomics at MHH. Jürgen Borlak is also an appointed Professor of Molecular Anatomy at Leipzig University, Germany, a Visiting Professor of Experimental Medicine at Uppsala University, Sweden and a Distinguished Visiting Professor at Trento University, Italy. He authors > 250 original publications and 25 book chapters and is the editor of the Handbook of Toxicogenomics.
Abstract:
Calcium sensitizers are used as an inotropic agent for the treatment of decompensated heart failure. In a preclinical safety study, the calcium sensitizer and PDEIII inhibitor EMD 82571 caused developmental defects in some fetuses. To explore mechanisms of toxicity, pregnant Wistar rats were dosed daily with either EMD 82571 (50 or 150 mg/kg/day) or Retinoic acid (12 mg/kg/day) on gestational days 6-11 and 6-17, respectively. Hypothesis driven and whole genome microarray experiments were performed with whole embryo, maternal liver, embryonic liver and malformed bone at gestational days 12 and 20. In the high dose EMD 82571 treatment group (150 mg/kg/day), approximately 58% of the fetuses presented cranial malformations, i.e. exencephaly and agnathia. Toxicogenomics revealed regulation of genes critically involved in osteogenesis, odontogenesis, differentiation & development and extracellular matrix and included bone y-carboxyglutamate (Bglap) which codes for osteocalcin. This protein functions as a hormone and plays a crucial role in fetal brain development as observed in osteocalcin knock out mice. Importantly, repression of osteocalcin and members of TGF-β/BMP signaling hampered osteo- and odontogenesis. Furthermore, EMD82571 impaired neurulation by inhibiting mid hinge point formation to cause neural tube defects. Taken collectively, a molecular rationale for the observed teratogenicity induced by EMD82571 is presented that links molecular initiating events with AOPs.
Biography:
Antonio Galvez completed his Ph.D at the age of 26 years from University of Granada, and held a postdoctoral position as visiting scientist in Merck, Sharp & Dome. He is the director of the Department of Health Sciences at the University of Jaen. He has published more than 160 papers in reputed journals and serving as an editorial board member of repute.
Abstract:
Biocidal compounds have been used since ancient times for preservation of the goods. Nowadays, they are widely used in many different fields and with many different purposes, such as sanitation (as in clinical settings), cleaning and disinfection (as in the food industry or at home), preservation (as in cosmetics and certain drug preparations), as surface coatings, odour protectants, and others. Biocidal preparations are consumed in large amounts and discharged to the environment. The toxicology of biocides and the impact of massive biocide use need to be reevaluated. Microorganisms have an amazing capacity for adaptation to toxic compounds. One adaptation strategy is the formation of biofilms. Bacteria living in biofilms are far more resistant to biocides and other chemical compounds, including antibiotics. Could exposure to biocides select for biofilm-forming potentially pathogenic bacteria with a higher capacity to cause infections in humans or being more difficult to eradicate? Another issue is the possible cross-resistance or co-resistance between biocides and antibiotics. Can the indiscriminate use of biocides facilitate the prevalence of antibiotic-resistance in the environments where biocides are used or where biocide wastes accumulate? Bacteria elicit non-specific mechanisms of tolerance to antimicrobial substances, some of which can provide protection against a variety of toxic compounds like heavy metals, biocides, and antibiotics. Most worrying, specific genetic determinants of biocide tolerance can be genetically linked with genes encoding antibiotic resistance. This raises the possibility of co-selection of antibiotic resistance by the use of biocides, even in the absence of antibiotic molecules. Application of biocides in combination with natural antimicrobial compounds could be a possible strategy to prevent a predicted impact of biocide use in the selection of antibiotic resistant bacteria.
Gunter Klambauer
Johannes Kepler University Linz, Austria
Title: Using Transcriptomics to Guide Lead Optimization in Drug Discovery Projects: Lessons Learned from the QSTAR Project
Biography:
Gunter Klambauer studied mathematics and biology and earned his PhD in Bioinformatics at the Johannes University Kepler University Linz. He has published influential machine learning methods for genetics, transcriptomics and toxicology. His approaches developed for cytotoxicity prediction performed best both at the NIEHS-NCATS-UNC DREAM toxicogenetics challenge in 2013 and at the recent Tox21 Data Challenge.
Abstract:
The pharmaceutical industry is faced with steadily declining R&D efficiency, and as a result, every year fewer new drugs reach the market despite increased investment. One major cause for this low efficiency is the frequent failure of drug candidates in late-stage development due to safety issues or previously undiscovered side effects. The question now arises which compounds to advance through early phases, in particular during lead optimization, based on the limited data available at these stages. High-throughput techniques for measuring transcripts are perfectly suited towards addressing this question. First attempts have already been made to identify compound-induced perturbations in transcriptomics networks with the aim of understanding biology and mechanisms of action. However, the utility of gene expression profiling for decision-making in early-stage pharmaceutical drug discovery has not yet been demonstrated. In this work, and for a series of eight drug discovery projects within a global pharmaceutical company, we analyzed to what extent gene expression data can help with decision-making during lead optimization across disease areas, targets and scaffolds. Disease areas included oncology, metabolic diseases, virology, and neuroscience. In three projects, gene expression data were clearly able to support “go/no-go†decisions. In three other projects the observed transcriptional effects were biologically relevant but their contribution to the decision-making process was limited. Overall, our studies show that gene-expression profiling is a powerful technique for the detection of adverse effects of compounds, and a valuable tool in early-stage drug discovery decision-making.
Biography:
A Wallace Hayes has authored 250 peer reviewed publications and is the Editor of Hayes' Principles and Methods of Toxicology, Human and Experimental Toxicology, Cutaneous and Ocular Toxicology, Food and Chemical Toxicology and Target Organ Toxicity Series. He is past Secretary-General of IUTOX, past treasurer of American Board of Toxicology, past president of American College of Toxicology, Toxicology Education Foundation, Academy of Toxicological Sciences and past councilor of Society of Toxicology. He is diplomate of American Board of Toxicology, Academy of Toxicological Sciences, American Board of Forensic Medicine, and American Board of Forensic Examiners and Fellow of Academy of Toxicological Sciences, Institute of Biology, American College of Forensic Examiners and American College of Nutrition and is registered toxicologist in the EU and certified nutrition specialist. He was honored by Society of Toxicology with its Merit Award, by Mid-Atlantic Society of Toxicology with its Ambassador Award, by American College of Toxicology with its Distinguished Scientist Award and by International Dose-Response Society with its Outstanding Leadership Award. He was named Distinguished Fellow by the American College of Toxicology and Fellow by the American Association for the Advancement of Science.
Abstract:
The 2-year rodent carcinogenicity test has been the regulatory standard for the prediction of human outcomes for exposure to industrial and agro-chemicals, food additives, pharmaceuticals and environmental pollutants for over 50 years. The extensive experience and data accumulated over that time has spurred a vigorous debate and assessment, particularly over the last 10 years, of the usefulness of this test in terms of cost and time for the information obtained. With renewed interest in the United States and globally, plus new regulations in the European Union, to reduce, refine and replace sentinel animals, this review offers the recommendation that reliance on information obtained from detailed shorter-term, 6 months rodent studies, combined with genotoxicity and chemical mode of action can realize effective prediction of human carcinogenicity instead of the classical two year rodent bioassay. The aim of carcinogenicity studies should not be on the length of time, and by obligation, number of animals expended but on the combined systemic patho physiologic influence of a suspected chemical in determining disease. This perspective is in coordination with progressive regulatory standards and goals globally to utilize effectively resources of animal usage, time and cost for the goal of human disease predictability.
Maria S Sepulveda
Purdue University, USA
Title: Role of miRNAs on Daphnia pulex response to cadmium exposure
Biography:
Maria S Sepulveda is a Professor of Ecotoxicology and Aquatic Animal Health at Purdue University. She earned a Doctorate in Veterinary Medicine degree from Universidad de Chile, Santiago, Chile; her Master of Science degree from University of Florida, Gainesville, Florida (Wildlife Ecology); and her Doctorate from the same University (Veterinary Sciences with a Toxicology concentration). Over the last 20 years, she has conducted research evaluating the sublethal effects of a wide-range of environmental contaminants on the physiology of numerous aquatic species. Specifically, her research has focused on understanding the effects of pollutants on reproduction and early life-stage development.
Abstract:
Daphnia pulex, a widely used toxicological model organism, is known for its sensitivity and quick response to cadmium (Cd). To interrogate the function of D. pulex microRNAs under Cd exposure, we analyzed the miRNA profiles of Cd-exposed D. pulex using Affymetrix Genechip 4.0 microarrays and validated miRNA expression by RT-PCR. MiRNA dpu-let-7 was identified as a stable expressed reference gene under Cd-exposure. Our research identified 25 and 21 differentially expressed miRNAs in the low (20 µg/L CdCl2) and high (40 µg/L CdCl2) concentrations, respectively. Next, miRNA target genes were predicted by Targetscan and RNA duplex. Predicted target genes revealed these miRNAs are related with cell death, DNA repair, calcium transport and hypoxia. A total of seven predicted target genes were selected for expression profile by RT-PCR and expression for two of the predicted target genes was negatively correlated with the expression of their regulator miRNA. Collectively, this research will advance our understanding on the role of miRNAs in response to heavy metal exposure.
Andrea Adamcakova
University of Iowa, USA
Title: Effects of Prenatal Inhalation Exposure to Copper Nanoparticles on Dams and Offspring in Mouse Model
Biography:
Andrea Adamcakova-Dodd has completed her PhD in Public Health from the University of Trnava, Trnava, Slovakia. She has been working as a toxicologist in the Pulmonary Toxicology Facility, in the Environmental Health Sciences Research Center from 2002 and has an extensive experience in the field of pulmonary toxicology. She has published more than 33 publications and one book chapter in Handbook of Systems Toxicology. Her main interest in recent years is a toxicity assessment of various xenobiotics after inhalation exposure during gestation and their effects on offspring.
Abstract:
Increasing number of individuals may be exposed to nanomaterials during pregnancy. Overarching goal of this investigation was to determine if prenatal inhalation exposure to Cu NPs has an effect on dams and offspring and if their Th1/Th2 cytokine profiles were affected. Physicochemical characteristics of Cu NPs were evaluated. Pregnant and non-pregnant mice (C57Bl/6J) were exposed to Cu NPs in the whole-body exposure chamber for 4 hrs/day on gestation day (GD) 3-19 (3.5 mg/m3). The results demonstrate that survival rate of pups at 7 wks of age was significantly lower if they were exposed to Cu NPs during gestation, compared to controls (73% vs. 93%). The average litter size, male/female ratio, birth weight as well as body size at birth were not different between Cu NP-exposed and control mice. Both pregnant and non-pregnant mice exposed to Cu NPs had significant pulmonary inflammation with increased number of neutrophils in the BAL fluid/mouse compared to pregnant and non-pregnant controls. Perivascular lymphoplasmacytic cuffing was found in the lungs of exposed mice and was more pronounced in the non-pregnant group. Similarly, levels of following cytokines (IL-12(p40), G-CSF, GM-CSF, KC, MCP-1, MIP-1α, MIP-1β, RANTES and TNF-α) in BAL fluid were significantly higher in non-pregnant than pregnant exposed mice. Histopathology evaluation of placentas did not find any pathological changes. No translocation of Cu NPs into the placenta or fetus was found using ICP-MS method. Expression of several Th1/Th2 or other immune response genes in pups spleens were found to be significantly up- or down-regulated. Prenatal exposure to Cu NPs caused a strong immunomodulatory effects in offspring. Biography
Susana Garcia de Arriba
Schaper & Brummer GmbH & Co. KG., Germany
Title: Human Safety of free Hydroquinone derived from Herbal medicinal products containing Uvae ursi folium
Biography:
Susana Garcia de Arriba studied Pharmacy at the University of Valencia, Spanien. Her M.Sc. in Pharmaceutical Science completed at the Faculty of Pharmacy,University of Gent, Belgium. She completed her PhD in Pharmacology at the University of Leipzig (Germany). She worked as postdoctoral fellow at the Rudolf-Boehm Institute of Pharmacology and Toxicology as well as at the Interdisciplinary Center for Clinical Research (IZKF), Neuro-immunological Cell Biology Unit,University of Leipzig. Since July 2008 works for the company Schaper & Brümmer as Scientific & Medical Expert inside of the department of Regulatory Affairs inSalzgitter Ringelheim, Germany. Her areas of expertise are Herbal Medicinal Products, Phytotherapy, processes of Aging, Neurodegeneration, mechanism of drug action and mechanism of drug toxicity.
Abstract:
Uvae ursi folium (bearberry leaf) has been traditionally used to treat symptoms of lower urinary tract infections. Arbutin, the major active constituent, is rapidly absorbed in the small intestine and undergoes hepatic conjugation to form hydroquinone (HQ) conjugates. Because arbutin is broken down to yield free HQ, concerns regarding the safety of free HQ have raised serious questions about the safety of herbal preparations containing extracts of Uvae ursi folium. Data on pharmacokinetics in humans helped to estimate human exposure to free HQ: 11 µg/kg body weight /day in urine after the therapeutic daily dose of 420 mg arbutin. The permitted daily exposure of free HQ in humans was estimated at 100 µg/kg body weight/day. Dietary sources of arbutin/HQ generate comparable free HQ exposure levels as therapeutic doses of Uvae ursi folium. No direct evidence have been found supporting the toxicity of free HQ derived from herbal medicinal products. On the other hand, the mutagenic potential of free HQ derived from a therapeutic dose of Uvae ursi folium extract (7.2 g Uvae ursi folium extract corresponding to 420 mg arbutin) was investigated in urine samples of healthy volunteers (n=12). Free and total HQ were firstly estimated in single urine samples. Both, the in vitro AMES assay and the in vivo micronucleus assay were negative for mutagenicity activity. Therefore, urine samples obtained from healthy volunteers receiving an Uva ursi folium extract at the same dose as proposed for therapeutic use bears no mutagenic risk.
- Track 4: Toxicology Approaches
Track 5: Drug Monitoring
Location: Hall 5
Chair
D Weissmann
Alcediag, France
Co-Chair
Raúl Bonne Hernández
Federal University of São Paulo, Brazil
Session Introduction
Farhad Kamali
Newcastle University, UK
Title: Involvement of genetics in poor outcomes in anticoagulation therapy
Time : 14:30-15:00
Biography:
Farhad Kamali is Professor of Human & Experimental Pharmacology at the Institute of Cellular Medicine, Newcastle University, United Kingdom. He has published well over one hundred articles in peer reviewed journals as well as book chapters. Professor Kamali serves on the editorial board of a number of journals in the areas of clinical pharmacology, pharmacogenetics and haematology. Prof Kamali’s research focuses on the elucidation of the mechanisms of drug-induced toxicity and in particular identifying the risk factors associated with poor outcomes in anticoagulation treatment of thromboembolic disease.
Abstract:
Warfarin is commonly prescribed for the treatment and prevention of thromboembolic disorders. Anticoagulation response to warfarin during the initiation of therapy is variable. This is mainly due to the drug’s narrow therapeutic window and the wide inter-individual variability in warfarin dose requirement which makes the prediction of an accurate dose for individual patients difficult despite the use of standard induction regimens and frequent INR monitoring. As a result, some patients who are sensitive to warfarin are at increased risk of bleeding due to over-dosing whereas some are at increased risk of thrombosis due to under-dosing. Approximately half of the variability in warfarin dose requirement is explained by patient age, body size and CYP2C9 and VKORC1 genes. A personalised approach to warfarin dosing using genetic information has the potential to improve the safety and efficacy of anticoagulation therapy. The author will be presenting the results of prospective trials exploring the potential benefits of pharmacogenetics-based therapy and the potential for future implementation of pharmacogenetics-guided therapy in the clinic setting.
D. Weissmann
Alcediag, France
Title: Innovative test to predict drug-induced neurotoxicity and psychiatric side effects
Time : 15:00-15:30
Biography:
Dinah Weissmann is General Manager at Alcediag, a company dedicated to innovation in diagnostic, and co-director of SYS2Diag, a joint venture between Alcediag and the CNRS dedicated to the biology of complex systems. Before Alcediag, she has served as Biocortech CEO and Chairman since 2001 and began her carreer was a Senior Scientist at Roussel Uclaf (now Sanofi-Aventis). Her research background includes an appointment as Research Director at the CNRS . as a co-founder of the CNRS Neuropharmacology lab at Lyon University. She was appointed by the French Ministry of Research to define the new national strategy for research and innovation.
Abstract:
Severe drug-induced psychiatric side effects as depression and suicide recently resulted in market withdrawal of compounds like Rimonabant, emission of FDA alerts (Champix, Roaccutane) or law suites (Paxil). Current non clinical safety studies, whether safety pharmacology or toxicity studies cannot detect these severe side effects leading to dramatic human deaths and expensive late withdrawals. RNA editing of the serotonin 2C receptor (5-HT2cR) has been shown to be altered in postmortem brains of depressed patients and suicide committers. Alcediag has characterized a specific RNA editing signature of the 5-HT2cR linked to depressed/suicide patients. By using next generation sequencing technology (Illumina), Alcediag determined the editing profiles of the serotonin 2C receptor in SH-SY5Y human neuroblastoma cell line, treated with 54 marketapproved drugs at 3 concentrations. These compounds were selected from various therapeutic classes (antidepressant, antipsychotic, anti-obesity, antiviral, anti-inflammatory, anti-fungic, antiepileptic, mood stabilizing agents and others) as potentially inducing suicidality (FDA warning label) or not (no psychiatric side effects reported). The screening could identify a specific ‘at risk signature’, similar to that found in post mortem brain of suicide patients. Clear dose-effect relationships were observed. An algorithm was generated to identify ’at risk’ compounds with 80% sensitivity and 90% specificity. This test is the first in vitro test able to characterize a potential pharmacotoxicity on the brain. Based on the same approach, a blood test was developped to assess the suicide risk in patients. First data exhibit high sensitivity and specificity. Taken together, those tests open new perspectives in personalized medicine in psychiatry.
Raul Bonne Hernandez
Bioinorganic and Environmental Toxicology - Labita, Brazil
Title: Toxicogenomics analysis of zebrafish (danio rerio) embryos reveals pathways involved in manganese-induced dementia
Time : 15:50-16:20
Biography:
I am Graduate In Chemistry (2000) and MSc in "Integrated Coastal Zone Management" (2003) at the University of Oriente. PhD in Chemistry (2009) and Post-Doctoral in Biochemistry at the University of Sao Paulo (2010). Professor of Environmental Chemistry and Toxicology at the Federal University of São Paulo. Expertise in Bioinorganic Chemistry, mainly in Chemical Speciation, Chemical Fractionation and Toxicogenomics approaches applied for Studies of Environmental Neuro(toxicology) of Metals with both developmental models Zebrafish embryos and primary cerebellar granule neurons cell culture.
Abstract:
Manganese (Mn) is essential for living organisms, playing an important role in nervous system function, bone mineralization, protein and energy metabolism, metabolic regulation and cellular protection. Nevertheless, chronic and/or acute exposure for this metal, mainly during early life stages can lead to neurotoxicity, but the mechanism for these events is still unclear. We hypothesize that exposure to Mn species induces differential neurotoxicogenomic alterations. Thus, the aim of the present study was to compare the toxicity of several and representing common aquatic chemical species of manganese, and to understand the mechanism of Mn-induced neurodisorders. Methods: The the toxic effects of the manganese (Mn(II)-Chloride, Mn(II)-Citrate and Mn(III)-Citrate) in embryos of Danio rerio was verified by chemical speciation, chemical fractioning, neurobehavioral and toxicogenomic approaches (DNA microarray and RT-PCR). The embryos of zebrafish were exposed during different development stage from 2 hours post fertilizations –hpf to 122 hpf, for 48 h, 72 h and 120 h. Results: We found a stage-specific increase of lethality, being more significant for embryos exposed for Mn(II)-Citrate, specially > 48 hpf. Additionally, we verified that the zebrafish embryos exposed for manganese (48- 120 hpf) showed significant Mn bioaccumulation, behavioral (locomotor and cognitive) impairment and finally disruption of genes associated with protein metabolism pathway. These genes (bcat2, cenpj, dpp4, eif2s1, ell2, erbb2ip, mmp2, myl6, sgce, slc14a2 and tcea3) are potentially associated with dementia (Parkinsonism and Alzheimer´s) too. Conclusion: These toxicogenomics findings suggest that early-life exposure for manganese may contribute to late-life neurodegeneration.
Dinora Vázquez-Luna
Universidad Veracruzana, Mexico.
Title: Biological indices of toxicity in tropical legumes grown in oil-contaminated soil
Time : 16:20-16:50
Biography:
Dinora Vázquez Luna has completed her PhD at the age of 30 years from Colegio de Postgraduados, Mexico. She is Full-time professor at the Faculty of Engineering in Agricultural Production Systems (FISPA), Universidad Veracruzana (UV). Researcher recognized by the National System of Researchers in Mexico. Currently, she is a member of the Academic Council of the Master and Doctorate in Agricultural Sciences, also conducts counseling doctoral thesis in Biotechnology. She has published nine papers in reputed journals and has been serving as a reviewer for international journals on topics related to Ecotoxicology and Environmental Toxicology.
Abstract:
This study evaluated the toxic effects of total petroleum hydrocarbons (TPH) on growth of the legumes Crotalaria incana L. and Leucaena leucocephala Lam., and on the development of soil microorganisms. The aim of this study was to generate user-friendly indicators of soil contamination to measure the toxic effects of TPH on growth of tow tropical legumes, and on the development of nitrogen-fixing soil microorganisms (rhizobial and free-living). The indices developed were the biological toxicity indices (BTI) and the toxicity potential index (TPIc) in higher plants. Growth and biomass accumulation in both plant species decreased with high pollutant concentrations. The EC50 and the NOEC were not identified for either species. The Phytotoxicity Relative Index showed that root length was most strongly affected by the oil, and the Impact Index on Nitrogen Fixer Microorganisms indicated that, despite damage to the root system, L. leucocephala rhizosphere bacteria doubled at 10,000 mg kg−1 TPH after of 240 days of exposure. Finally, the TPIc revealed that C. incana was more sensitive than L. leucocephala to chronic TPH toxicity and might strongly depend on beneficial soil bacteria.
Wafa Soudani
Annaba Medical College, Algeria
Title: Tolerance of imatinib, dasatinib and nilotinib in the treatment of chronic leukemia myeloid
Time : 16:50-17:20
Biography:
Wafa Soudani received Doctorate on pharmacy from Annaba medical college-Algeria. She has continued study in Algiers medical college- Algeria where she was diplomated at the age 27 years and she become a teacher master assisting in chemical chemistry in Annaba Medical college-Algeria at the age 29 years. After that, she has presented many of papers in a lot of international congress (France, Turkey, and Tunisia) as communications and she have published 4 papers in Journal Annals of Clinical Biology, Journal of Clinical Chemistry Laboratory Medicine and Turkish Journal of Agriculture and Natural Science.
Abstract:
Background: The Inhibitors of Receivers with Tyrosin Kinase are new therapeutic targets recently explored with an aim of increasing the selectivity of antitumor action, the main aim was to evaluate the tolerance with the Inhibitors of Receivers with Tyrosin Kinase among cancer patients. Method: A retrospective descriptive study was carried out into a series of thirty-three case (33) cancer patients reached of chronic Leukemia myeloid follow-ups on the service of hemato -oncology CHU Annaba during December 2013 to April 2014. Results & Discussion: The study of the tolerance showed that Imatinib: Glivec® gave only one case with complications colopathy type and respiratory allergy; with disappearance of the osseous pains and the arterial hypertension obtained with Imatinib: Imatib®; what confirms a good tolerance of the specialty of Glivec® compared to Imatib®. We did not note any complication for Dasatinib and Nilotinib, with reduction in the specific effects (Dasatinib gave 16.67% of the osseous pains, Nilotinib 9.09% of osseous pains and 9.09% of myalgia), reduction in the asthenia (33.33% for Dasatinib and 9.09% for Nilotinib); this testifies to a better tolerance of the new inhibiting molecules of receivers with Tyrosin Kinase Dasatinib and Nilotinib compared to the molecule of reference Imatinib. Conclusion: Through these data we raise the interest of selection of the therapeutic protocols and the importance of a strict monitoring of the undesirable effects of therapeutic targeted in order to ensure better followed therapeutic for the cancer patients.
Eman Alaaeldin Adbelfattah
Cairo University, Egypt
Title: Biomolecules oxidation and antioxidant enzymes response as a result of injection of oxidative stressors into 5th instar of Schistocerca gregaria
Time : 17:20-17:50
Biography:
Eman Alaaeldin Abdelfattah has graduated from Faculty of Science, Cairo University, Egypt. She is an instructor at Entomology Department, Faculty of Science, Cairo University, Egypt.
Abstract:
Oxidative stressors may cause oxidative stress by generation of reactive oxygen species including free radicals and non free radicals, and therefore enhance oxidative damage to macromolecules. The aim of this work is not only to measure of products of ROS-oxidized macromolecules, but also to determine activity of antioxidant enzymes that were measured using spectrophotometric method and alkaline comet assay. The results show that each three stressors that were injected separately lead to formation of lipid peroxidation, protein carbonylation, and DNA strand breaks. Antioxidant response mechanism of the cells, as indicated from antioxidant enzymes level, lead to elevation of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) when compared to control (pvalue<0.05).
Fahim Nawaz
University of Oxford, United Kingdom
Title: Deciphering Selenium Mediated Physiological and Biochemical Mechanisms for Improving Drought Tolerance in Wheat
Biography:
Dr Fahim Nawaz completed his PhD at the age of 30 from University of Agriculture, Faisalabad, Pakistan. He worked as a visiting postgraduate research scholar at the Department of Molecular Ecophysiology and Stress Adaptation, Georg-August Universtat, Gottingen, Germany and Nuclear Institute for Agriculture and Biology, Faisalabad, Pakistan for six months and one year, respectively during his doctoral studies. Currently, he is working as a postdoctoral fellow at the Department of Plant Sciences, University of Oxford, United Kingdom. Dr Nawaz participated/presented his research findings in many national/international conferences and has produced more than 27 publications including research/review papers, popular articles and one book. His research is focused on the biogenesis of chloroplasts and other plastids in plants, particularly in relation to the import of nucleus-encoded proteins and the role of the ubiquitin-proteasome system.
Abstract:
Drought stress is a major environmental problem that severely restricts plant distribution and crop production worldwide. Water shortage, due to frequent droughts, requires future farming and food systems to be better adapted to a range of environmental stresses. Selenium (Se) is considered an essential element for humans, animals and plants. The notion that Se helps to protect plants against abiotic stresses needs to be further explored by addressing the question of whether improved stress tolerance is directly due to regulation of various physiological and biochemical mechanisms by Se. The study was planned to evaluate the effects of exogenous Se supply in wheat under drought stress conditions. We report that Se mitigates drastic effects of water stress through maintenance of turgor, enhanced gas exchange characteristics, accumulation of osmoprotectants and increased activity of antioxidant machinery. The detection by ICP-OES showed that Se regulated processes facilitated the uptake of nutrients such as iron (Fe), potassium (K), zinc (Zn), magnesium (Mg), sodium (Na) and calcium (Ca) that ultimately improved the yield and quality of wheat grains under water deficit conditions. Moreover, the experiments with different methods of exogenous Se supply viz. Se seed priming, fertigation and foliar spray demonstrated that seed priming is only effectual at early stages of crop growth, whereas Se foliar spray is the most effective method for Se translocation and accumulation within water stressed wheat plants. These data suggest the usefulness of Se in improving drought tolerance in crop plants.
Eva Lima Castro Oliveira
Institute of Environmental Assessment and Water Research, Spain
Title: Molecular mechanisms of Retinoic Acid isomers in zebrafish eleutheroembryos
Biography:
Dr. Oliveira has gained experience in using terrestrial and aquatic model organisms, for environmental risk assessment. She has a history of scientific productivity and has collaborated in research projects. As a doctoral candidate at the Aveiro University (Portugal) her PhD thesis was untitled “Toxicogenomics of natural and anthropogenic effectors in eleutheroembryosâ€. She received her Doctoral degree in October 2013. Her PhD training provided Dr. Oliveira with knowledge of many different molecular techniques.Dr. Oliveira went to IDAEA-CSIC Barcelona (Spain) with a Research fellowship. To date Dr. Oliveira has co-authored 5 peer-reviewed papers, one book chapter.
Abstract:
The zebrafish is considered a promising alternative test model for developmental toxicity testing. The normal vertebrate development requires appropriate amounts of Retinoic acid (RA). All-trans retinoic acid (atRA) and 9-cis retinoic acid (9cRA) are potent metabolites of Vitamin A and operate by affecting gene expression through the retinoic acid metabolic pathway. atRA or 9cRA can bind to retinoic acid receptors (RARs) and the 9cRA isomer bind to retinoid X receptors (RXRs) with more affinity. The exogenous application of retinoid isomers to zebrafish is considered to have deleterious effects of varying magnitudes through fish developmental stages. In this study, we report both phenotypic and transcriptomic effects of zebrafish eleutheroembryos exposed RA isomers for 24h and 72h. Nevertheless at sub-lethal concentrations the both RA isomers showed a differential regulation for 3623 features (2-Fold, p<0.01). The transcriptomic analyses reveal profiles describing different patterns, which allow individualizing the action of both isomers. Nevertheless the differential gene expression of both isomers is stable during the period of exposure. We concluded that the 9cRA response appears to be deactivated upon time, perhaps through its intracellular degradation and/or isomerization, and that the presence of any compound masking or anyway interfering with their effective levels may cause harmful effects to developing vertebrate embryos. Our data suggests that Retinoids effects on early embryonic zebrafish development are stage-specific and is related in particular to the neuronal system behavior. Also, the regulation of the Vitamin-A dietary intake may be a special concern for future studies on the development of zebrafish eleuteroembryos.
Amare W Nigatu
University of Bergen, Norway
Title: Respiratory symptoms, fractional exhaled nitric oxide & endotoxin exposure among female flower farm workers in Ethiopia
Biography:
Amare W Nigatu is a Ph.D candidate in Department of Global Public Health and Primary Care in the University of Bergen.
Abstract:
Greenhouse workers at flower farms had higher prevalence of blocked nose than workers outside, which may indicate the presence of rhinitis. Endotoxin exposure was low. There were few workers with objective signs of airway inflammation; this might be because the mean working time in the greenhouses was only two years. We suggest further studies to evaluate the effect of longer employment and exposure time as well as to investigate possible exposure to pesticides and other components in the bio-aerosols.
Vinita Chauhan
Consumer and Clinical Radiation Protection Bureau, Canada
Title: Comparative analysis of genomic profiles from human cell lines exposed to alpha particle radiation
Biography:
Vinita Chauhan is a Research Scientist at the Consumer and Clinical Radiation Protection Bureau, Health Canada. She has graduated with a PhD in Biochemistry from the University of Ottawa and has been employed at Health Canada for the past 12 years. The focus of her research has been to understand the mechanistic basis for adverse health effects associated with exposure to ionizing radiation. Through this work, she gained expertise in genomic and proteomic techniques and has published over 20 manuscripts in peer-reviewed journals and presented both nationally and internationally. During the past 5 years, she has co-led Health Canada’s science activities in a Genomics Research and Development Initiative, which includes a sub-project to identify transcriptosome changes in human derived cell-lines following exposure to alpha particle radiation.
Abstract:
Alpha particle radiation has become an increasing public health concern. The general population is exposed through a variety of means, including ubiquitously from the environment (radon gas), when using emerging radiotherapy modalities, accidently through occupational exposures and potentially from a malicious terrorist threat.Previous work in our laboratory has identified genes responsive to alpha particle radiation in five human-derived cell-lines which have included monocytes (THP-1), lung epithelial cells (A549), keratinocytes (HEKn), lung fibroblasts (HFL-1) and isolated peripheralblood mononuclear cells (PBMC) from healthy individuals. This report provides a meta-analysis of these previously published studies. The results from this analysis indicate that at relatively small doses of radiation exposure (0.5-1.5 Gy), each of the cell-types elicited a response, modulating numerous transcripts.All cell-types expressed a unique sub-set of genes. Thirty-six genes were common to all five cell-types. Biological processes associated with these genes included cell cycle/mitosis (FBXO5 ZWILCH CDKN1A DHFR MCM3 MCM7), telomere maintenance (ACD, HIST1H2BD, HIST1H4C) and DNA Replication (CDKN1A MCM3 MCM7). Hierarchical clustering of these transcripts separated cell-types into two main groups by specific tissue types. Overall, radiation exposure has been shown to elicit cell-dependent differential genome-wide effects. However, despite distinctions, the end outcome is central to the process of DNA damage repair. By highlighting common and differential responses between cell-lines at the transcriptional level with their associated pathways/networks, an understanding of the cellular alpha particle radiation response has been established along with the identification of potential biomarkers of exposure.
Sumitra Arora
ICAR-National Research Centre for Integrated Pest Management, India
Title: Potentiation of toxicity of organophosphate pesticides in mixtures
Biography:
Sumitra Arora has completed her PhD, as in-service candidate, from Indian Agricultural Research Institute on ‘Safety evaluation of pesticides on cabbage crop’; and Postdoctoral studies from CSIRO, South Australia, under a project, “Assessment of toxicities of pesticides in mixtures using in-vitro and in-vivo studiesâ€. She is Principal Scientist at ICAR-NCIPM, a premier integrated pest management centre. Her area of specialization is organic chemistry and pesticide residue analysis. She has published more than 25 papers in reputed International and National Journals; and has reviewed several research articles for international journals.
Abstract:
Anticholinesterase inhibiting insecticides are likely to co-occur in environment as mixtures. This raises the possibility of antagonistic, additive, or synergistic neurotoxicity in exposed organisms. Acetylcholinesterase (AChE) inhibition has been demonstrated to be a useful biomarker for exposure to organophosphorous (OP) insecticides in many environments. The objective of this study was to investigate the response of housefly (Musca domestica) head AChE (HF-AChE) exposed to five OPs as individual compounds and their binary mixtures under in vitro conditions. To examine the effects of oxidation on OP potency in the HF-AChE system, bromine water was used as an oxidizing agent. The sensitivity of HF-AChE increased significantly to oxon analogues of chlorpyrifos (CPF), malathion (MLT) and triazophos (TRZ). Monocrotophos (MCP) and profenofos (PRF) did not exhibit any significant differences in toxicity under oxidised and un-oxidized conditions. The concentration addition model, the combination index–isobologram equation and the toxic unit approach, all three models, provided similar predictions for toxicological interaction of 10 binary combinations of OPs under oxidized and un-oxidized conditions. The antagonistic effects of the binary combination of OPs (CPF+PRF, CPF+MLT, MCP+MLT, PRF+MLT, MLT+TRZ and PRF+TRZ), was observed under oxidized conditions. This may be due to dispositional and/or receptor antagonism. Most of the binary combinations under un-oxidized conditions exhibited synergistic responses. Triazophos showed very strong synergism in binary combinations with CPF, MCP and PRF. Contrarily only CPF+TRZ exhibited synergism under oxidized conditions. The results indicated differential toxicity of binary combinations of OPs under oxidized and un-oxidized conditions.
A P Das
Siksha O Anusandhan University, India
Title: Biosensors for rapid detection of endotoxins in pharmaceutical drugs and biological fluids
Biography:
A.P. Das has received his PhD in Biotechnology (2013) work place CSIR-IMMT and registered at Siksha OAnusandhan University, Bhubaneswar. Presently he is working as an Assistant Professor (since July 2009), at Center of Biotechnology, SOA University, Bhubaneswar, Odisha, India. He is a member of the International Union for the Conservation of Nature (IUCN) Species Survival Commission Horseshoe Crab Specialist Group, life member of Association of Microbiology (AMI), India and life member of Indian Society of Technical Education (ISTE), India.
Abstract:
Endotoxin control is of paramount importance primarily for health and safety issues. There are many sectors demanding mandatory monitoring of endotoxin levels, such as food industry, pharmaceutical, health care, agriculture, and utilities, defense and the environment. Mortality and morbidity rates due to endotoxin remain paramount high and have not improved significantly over the past 25 years. The outcome of failure to detect and monitor endotoxin levels can result in serious sequelae in survivors and large scale deaths. These necessities the need for a rapid, sensitive and non-invasive biosensor for detection and monitoring of endotoxin levels even in extremely small concentrations. The proposed method of endotoxin detection is based on the use Chromogenic substrate, which monitors, the color development of the Horseshoe crab amoebocyte lysate assay in response to endotoxin. Our proposed strategy can be adapted to detect endotoxin detection in pharmaceutical drugs and biological fluids with 0.02EU/ml. Due to its rapidity, portability and sensitivity the proposed chromogenic sensor is ideally suited for wide-spread use in endotoxin detection.
G Balaji
Clintox Bio Services, India
Title: Mast cell stabilizing and anti-anaphylactic activity of aqueous extract of green tea (Camellia sinensis)
Biography:
G Balaji has joined the Clintox Bioservices as a research associate and later he was promoted as toxicologist at Clintoc Bioservices.
Abstract:
Green tea (Camellia sinensis) is one of the most popular and widely consumed beverages in the world. In the current study, aqueous extract of green tea (C. sinensis) was evaluated for mastcell stabilizing and anti-anaphylactic activities. Green tea extract (11, 13, 15 mg/ml) significantly (P <0.05) inhibited compound 48/80-induced rat mesentric mast cell de-granulation in a dose dependent manner. Anti-anaphylactic activity of green tea extract was performed in female mice. At a dose of 400, 500, 600 mg/kg BW, green tea extract showed significant reduction in the mortalityof mice subjected to anaphylactic shock by compound C48/80. Ketotifen was used for comparison.In addition, IR and UV–Visible spectroscopy analysis of green tea extract revealed the presenceof functional groups of bioactive compounds. These results suggest that green tea could be useful inthe treatment of asthma and allergic rhinitis.
- Young Research Forum
Session Introduction
Gazo I
University of South Bohemia in Ceske Budejovice, Czech Republic
Title: In vitro effect of bisphenol A on DNA integrity and intracellular signaling in sturgeon (Acipenseruthenus) sperm
Time : 17:50-18:00
Biography:
Gazo I is a 4th year PhD student at the University of South Bohemia, Czech Republic. Her PhD topic is “The role of reactive oxygen species and protein phosphorylation in fish sperm”. During her PhD studies, she published, as a first author, two manuscripts describing the influence of environmentally relevant concentrations of vinclozolin on sterlet (Acipeser ruthenus) spermatozoa and the effect of reactive oxygen species on carp (Cyprinuscarpio L.) sperm and co-authored 6 publications in the same field.
Abstract:
Among endocrine disrupting chemicals (EDCs), the xenoestrogen bisphenol A (BPA) deserves particular attention due to its widespread human and wildlife exposure. Besides hormonal effects, BPA has been suspected to be responsible for adverse effects on reproductive ability of various species. In most fish species, during natural reproduction, sperm is released to external environment that contains pollutants, such as BPA, affecting spermatozoa functions. Spermatozoa are highly specialized, transcriptionally inactive cells, and its major function is delivery of paternal DNA into the oocyte. Therefore motility and DNA integrity are the main prerequisites of successful fertilization. Most of the processes in spermatozoa are regulated by osmotic/ionic signaling and protein post-translational modifications, such as protein phosphorylation. Thus negative effects of water pollutants on sperm physiology can lead to significant reduction in biodiversity which can be crucial for sturgeons as endangered species. In the present study, we used the small sturgeon (Acipenser ruthenus) sperm to investigate in vitro the potential deleterious effects of endocrine disrupt or bisphenol A on spermatozoa physiology, DNA integrity, phosphatase activity and protein phosphorylation pattern. The result of this study showed that even at low doses (down to 1 μM), BPA could decrease sturgeon sperm motility and velocity, induce DNA fragmentation and change the pattern of protein phosphorylation. BPA was also shown to induce oxidative stress in sturgeon spermatozoa. Based on the obtained results, the use of in vitro sperm assays may provide a novel and efficient means for evaluating the effect of xenobiotics in aquatic environment on sturgeon.