Advances in Toxicology The latest articles from Hindawi Publishing Corporation © 2015 , Hindawi Publishing Corporation . All rights reserved. Dramatic Increase in Cerebral Blood Flow following Soman Intoxication If Signs of Symptoms Can Be Seen Sun, 11 Oct 2015 06:47:15 +0000 Organophosphate poisoning is associated with adverse effects on the central nervous system such as seizure/convulsive activity and long term changes in neuronal networks. This study report an investigation designed to assess the consequences of Soman, a highly toxic organophosphorus compound, exposure on regional blood flow in the rat brain and peripheral organs. We performed repeated blood flow measurements in the same animal, using the microspheres technique, to characterize changes in regional blood flow at different times after Soman intoxication. In addition, the cardiopulmonary effects of Soman were followed during the intoxication. Administration of Soman (1 LD50; 90 µg/kg, s.c.) to anaesthetized rats produced a decrease in blood acetylcholinesterase activity in all animals tested. Although, only six out of ten rats showed signs of poisoning like a decrease in respiratory rate, the results show that only animals with significant signs of poisoning demonstrated an increase in cerebral blood flow. We conclude that it is of great importance to treat all data individually. An overall mean can easily be misinterpreted and conceal important effects. We also conclude that the increase in cerebral blood flow has an important role in the effect on respiration and that this effect is independent of the blood acetylcholinesterase activity. Ann Göransson Nyberg and Gudrun E. Cassel Copyright © 2015 Ann Göransson Nyberg and Gudrun E. Cassel. All rights reserved. Cytotoxicity Induced by Tetracyclines via Protein Photooxidation Tue, 24 Mar 2015 06:56:12 +0000 Background. Bacterial ribosomes have been considered the principal targets of tetracyclines. Recently, new clinical data has shown how other biomacromolecules are involved in the cellular damage of bacteria. Researchers are now reconsidering the pharmacological classification of tetracyclines, not only based on their semisynthetic or synthetic generations but also following the new mechanisms of action that are progressively being discovered. Materials and Methods. The toxicity properties of seven tetracycline derivatives (tetracycline, oxytetracycline, demeclocycline, chlortetracycline, doxycycline, minocycline, and meclocycline) were investigated in vitro using a cell line of human keratinocytes. Cells were irradiated in the presence of tetracyclines for different durations and at three different intensities of light. The investigation of protein oxidation was set up using model proteins to quantify the formation of carbonyl groups. Results. After incubation and irradiation with UV light, the viability of keratinocytes was assessed with half the maximal inhibitory concentration for doxycycline, demeclocycline, chlortetracycline, and tetracycline. No phototoxicity was observed for oxytetracycline, meclocycline, and minocycline. Conclusions. This study provides evidence that tetracycline’s derivatives show different photobehaviour according to their chemical properties due to different reactive groups on the same molecular skeleton. Domenico Fuoco Copyright © 2015 Domenico Fuoco. All rights reserved. Bisphenol A Induces Apoptosis in Liver Cells through Induction of ROS Wed, 11 Feb 2015 10:01:47 +0000 Oxidative stress mechanisms are involved in hepatotoxicity. The liver is reported to be affected by bisphenol A (BPA) in animals studies and has been also reported to possess hepatic toxicity. This study aimed to examine association between liver health status and the effects of BPA on the antioxidant defense systems and liver biomarkers. BPA (0, 2, 10, and 50 mg/kg) body weight was mixed in corn oil and intraperitoneally administered every forty-eight hours for 30 days in dose-dependent manner. There was no significant difference between the body weight and weight of rat liver in BPA-treated groups and control groups. The study results show that the levels of malondialdehyde (MDA) and hydrogen peroxide (H2O2) increased after exposure to BPA. However, the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-PX) were significantly (, , and , resp.) decreased at 50 mg/kg dosage. Liver markers activities such as lactate dehydrogenase (LDH), glutamic-oxalacetic transaminase (GOT), and glutamic-pyruvic transaminase (GPT) were significantly increased, while γ-glutamyl transferase (γ-GT) activity was decreased. BPA exposure increased activity of liver biomarkers indicating liver hyperactivity. Analysis of the liver section provided essential evidence of liver apoptosis. Moreover, BPA may lead to induced toxic response of liver oxidative system. Ansoumane Kourouma, Chao Quan, Peng Duan, Suqin Qi, Tingting Yu, Yinan Wang, and Kedi Yang Copyright © 2015 Ansoumane Kourouma et al. All rights reserved. Systems Biology and Synthetic Biology: A New Epoch for Toxicology Research Mon, 26 Jan 2015 12:42:30 +0000 Systems biology and synthetic biology are emerging disciplines which are becoming increasingly utilised in several areas of bioscience. Toxicology is beginning to benefit from systems biology and we suggest in the future that is will also benefit from synthetic biology. Thus, a new era is on the horizon. This review illustrates how a suite of innovative techniques and tools can be applied to understanding complex health and toxicology issues. We review limitations confronted by the traditional computational approaches to toxicology and epidemiology research, using polycyclic aromatic hydrocarbons (PAHs) and their effects on adverse birth outcomes as an illustrative example. We introduce how systems toxicology (and their subdisciplines, genomic, proteomic, and metabolomic toxicology) will help to overcome such limitations. In particular, we discuss the advantages and disadvantages of mathematical frameworks that computationally represent biological systems. Finally, we discuss the nascent discipline of synthetic biology and highlight relevant toxicological centred applications of this technique, including improvements in personalised medicine. We conclude this review by presenting a number of opportunities and challenges that could shape the future of these rapidly evolving disciplines. Mark T. Mc Auley, Hyunok Choi, Kathleen Mooney, Emily Paul, and Veronica M. Miller Copyright © 2015 Mark T. Mc Auley et al. All rights reserved. Risk Assessment of Heavy Metals in Imported Frozen Fish Scomber scombrus Species Sold in Nigeria: A Case Study in Zaria Metropolis Mon, 05 Jan 2015 10:03:39 +0000 This study assesses the likely health risks to human contamination of heavy metals from fish consumption. The analysis of the idea of fish destination and status (fishing area) for heavy metals was determined by the assessment of its risk limits (daily intake of metal and health risk index). Variations in the accumulation of heavy metals concentrations were between various tissues/organs (skin, muscle, gills, liver, intestine, kidneys, brain, and bones) across the batches of two fishing origins. Post hoc (Duncan) multicomparison shows that there are significant differences () across batches. The concentrations of heavy metals analyzed, in the investigated tissues of Scomber scombrus, showed higher levels of heavy metals accumulations in the order: and were above the recommended safety limits outlined by FAO/WHO. However, the consumer’s health risk with the consumption of fish muscles tissues shows that there are greater tendencies for cadmium, lead, and mercury exposure. Also consumption of Scomber scombrus species above the recommended daily intake (stated in this study) might lead to ingestion of heavy metals at unacceptable concentrations. Abdullahi Abubakar, Adamu Uzairu, Patricia Adamma Ekwumemgbo, and Oluwole Joshua Okunola Copyright © 2015 Abdullahi Abubakar et al. All rights reserved. Influence of Different Doses of Levofloxacin on Antioxidant Defense Systems and Markers of Renal and Hepatic Dysfunctions in Rats Thu, 01 Jan 2015 11:04:27 +0000 Levofloxacin (LFX) is a broad spectrum fluoroquinolone antibiotic used in the treatment of infections such as pneumonia, chronic bronchitis, and sinusitis. The present study assessed the likely toxic effect of LFX on hepatic and renal tissues in rats. Twenty male Wistar rats were randomly divided into four treatment groups: A: control, B: 5 mg/kg bw LFX (half therapeutic dose), C: 10 mg/kg bw LFX (therapeutic dose), and D: 20 mg/kg bw LFX (double therapeutic dose). After seven days of administration, result indicated significant increase in plasma ALT, AST, and ALP activities in the treated groups compared to control. Also, there was a significant increase in plasma creatinine, urea, and total bilirubin in the treated groups relative to control. Plasma total cholesterol, HDL-cholesterol, LDL-cholesterol, and triglycerides also increased significantly in the treated groups relative to control. Also, hepatic MDA level increased significantly in all the treated groups. However, hepatic SOD, catalase, and GST activities were significantly reduced in the LFX-treated animals. Moreover, GSH and ascorbic acid levels were significantly decreased in the LFX-treated groups relative to control. In conclusion, three doses of levofloxacin depleted antioxidant defense system and induced oxidative stress and hepatic and renal dysfunctions in rats. Ebenezer Tunde Olayinka, Ayokanmi Ore, and Olaniyi Solomon Ola Copyright © 2015 Ebenezer Tunde Olayinka et al. All rights reserved. Chemical Exposure Generates DNA Copy Number Variants and Impacts Gene Expression Tue, 30 Dec 2014 08:24:33 +0000 DNA copy number variation is long associated with highly penetrant genomic disorders, but it was not until recently that the widespread occurrence of copy number variation among phenotypically normal individuals was realized as a considerable source of genetic variation. It is also now appreciated that copy number variants (CNVs) play a role in the onset of complex diseases. Many of the complex diseases in which CNVs are associated are reported to be influenced by yet to be identified environmental factors. It is hypothesized that exposure to environmental chemicals generates CNVs and influences disease onset and pathogenesis. In this study a proof of principle experiment was completed with ethyl methanesulfonate (EMS) and cytosine arabinoside (Ara-C) to investigate the generation of CNVs using array comparative genomic hybridization (CGH) and the zebrafish vertebrate model system. Exposure to both chemicals resulted in CNVs. CNVs were detected in similar genomic regions among multiple exposure concentrations with EMS and five CNVs were common among both chemicals. Furthermore, CNVs were correlated to altered gene expression. This study suggests that chemical exposure generates CNVs with impacts on gene expression warranting further investigation of this phenomenon with environmental chemicals. Samuel M. Peterson and Jennifer L. Freeman Copyright © 2014 Samuel M. Peterson and Jennifer L. Freeman. All rights reserved. Indium Titanium Oxide Nanoparticles Induced Hepatic Damage: Hepatoprotective Role of Novel 2-Imino-4-methyl-1, 2-Dihydropyrimido [5, 4C] Quinoline-5(6H)-one Tue, 09 Dec 2014 11:01:20 +0000 Protective role of 2-imino-4-methyl-1, 2-dihydropyrimido [5, 4C] quinoline-5(6H)-one (IMDHPQ) in indium titanium oxide nanoparticles (InTiO NPs) induced hepatotoxicity was analyzed. InTiO NPs were synthesized and given orally to albino rats to assess their hepatotoxicity. NPs mediated oxidative stress and liver tissue pathology were analyzed. Altered antioxidants (GSH, GPx, and catalase) and, biochemical (SGOT, SGPT, ALP, total protein, and total bilirubin) and histopathological changes were observed due to the oxidative stress caused by InTiO NPs. Varying effects of IMDHPQ on each parameter were observed in the present study. The altered parameters of InTiO NPs exposed rats might be due to the oxidative stress caused by NPs and hepatoprotective or ameliorative efficacy of quinoline compound IMDHPQ on signaling and molecular mechanism needs further study. Dinesh Bheeman, Sinjula Cheerothsahajan, Sathish Sugumaran, Sankaran Mathan, Ramesh Mathan, Sivanesan Dakshanamurthy, Ranjithkumar Rajamani, and Chandar Shekar Bellan Copyright © 2014 Dinesh Bheeman et al. All rights reserved. Genotoxicity Study with Special Reference to Comet Test in the Blood Cells of Workers Exposed to Sewage Water Sun, 23 Nov 2014 09:08:55 +0000 Awareness among sewage workers to occupational exposure is growing slowly in many developing countries. Lead (Pb) and cadmium (Cd) are present in sewage water and workers are exposed to these metals as a result of unprotected handling. These heavy metals exposures are responsible for DNA damage and lowering blood total iron (Fe) concentration. Zinc (Zn) is an element for promoting metallothionine expression and binds the free Cd. The total suspended solids (TSS), total dissolved solids (TDS), Pb, and Cd were estimated in sewage water. The whole blood Zn and Fe concentration and Pd and Cd were also estimated. Genotoxicity as indicated by DNA damage was studied by comet assay. It was observed that there were significant differences () of Pb and Cd concentration in blood for the sewage workers when compared with control population. DNA damage was also observed to be significantly () higher in the exposed groups but their blood Fe concentration was significantly lower, which may be the reason for their tendency for retention of blood Cd and make them more susceptible. This study also indicated that aged workers had higher blood Zn concentrations as compared to the younger (working < 20 years) workers. This may indicate a possible adaptive response. The present study proposes that younger (working < 20 years) group is more susceptible as compared to aged group (working > 20 years). Rajlaxmi Basu, Soumendra Nath Talapatra, Aniruddha Mukhopadhyay, Moumit Roy Goswami, Siddhartha Sankar Ray, Prantar Chakrabarti, Shidharth Sankar Ram, Mathummal Sudarshan, Anindita Chakraborty, Anjan Dasgupta, Uday Chand Ghosh, and Sila Chakrabarti Copyright © 2014 Rajlaxmi Basu et al. All rights reserved. Modulation of Tinospora rumphii and Zinc Salt on DNA Damage in Quinoline-Induced Genotoxicity and Hepatotoxicity in Male Albino Mice Thu, 20 Nov 2014 09:15:03 +0000 Tinospora rumphii (T. rumphii) is a folkloric medicinal plant that is widely distributed in Asia and Africa. It has been widely used by locals to treat many diseases including jaundice, which is a manifestation of liver damage. We investigated the action of T. rumphii crude extract together with zinc sulphate, a known tumor modulator, on hepatic injuries induced by intraperitoneal (i.p) injections of quinoline on albino mice. The hepatotoxic effect was assessed by bilirubin concentration in the blood serum, while the genotoxic effect was determined by single-cell gel electrophoresis (SCGE). The mice orally fed with the crude extracts, following quinoline exposure, had reduced serum bilirubin concentration and DNA damage. Mice treated with Zinc sulphate, on the other hand, had remarkably reduced DNA damage on hepatocytes. Our findings showed that hepatoprotective potential of T. rumphii extract is dose-dependent and that utilization of the extract as medicinal remedy must be strictly monitored, while zinc was proven to reverse genotoxic effect of quinoline. This study unraveled the potential of T. rumphii extract and zinc as important hepatoprotective agents for future treatment of hepatic damage caused by chemotherapeutic agents used in cancer treatment. Roger Salvacion Tan and Lydia M. Bajo Copyright © 2014 Roger Salvacion Tan and Lydia M. Bajo. All rights reserved. Evaluating Systemic Toxicity in Rabbits after Acute Ocular Exposure to Irritant Chemicals Wed, 19 Nov 2014 08:47:39 +0000 Acute systemic toxicity via ocular exposure route is not a well understood aspect. Any material/drug/chemical that comes in contact with the eye can evade the first pass metabolism and enter the systemic circulation through the conjunctival blood vessels or via the nasolacrimal route. In this study, the effect of ocular irritant chemicals on the systemic toxicity was assessed in rabbit. Eyes of rabbits were exposed to known ocular irritant (cetyl pyridinium chloride, sodium salicylate, imidazole, acetaminophen, and nicotinamide) for 24 h and scored. After a period of 72 h, blood was collected from the animals for examining the hematological and biochemical parameters. The animals were then sacrificed and the eyes were collected for histopathology and cytokine analysis by ELISA. Splenocyte proliferation was assessed by tritiated thymidine incorporation assay. The liver and brain of the treated animals were retrieved for evaluating oxidative damage. The chemicals showed moderate to severe eye irritation. Inflammation was not evident in the histopathology but proinflammatory markers were significantly high. The splenocyte proliferation capacity was undeterred. And there was minimal oxidative stress in the brain and liver. In conclusion, acute exposure of ocular irritants was incapable of producing a prominent systemic side effect in the current scenario. Reshma Sebastian Cherian and Mohanan Parayanthala Valappil Copyright © 2014 Reshma Sebastian Cherian and Mohanan Parayanthala Valappil. All rights reserved. Investigations of the Biological Effects of Airborne and Inhalable Substances by Cell-Based In Vitro Methods: Fundamental Improvements to the ALI Concept Wed, 12 Nov 2014 11:08:30 +0000 The state of the art for cell-based in vitro investigations of airborne and inhalable material is “air-liquid interface” (ALI) technology. Cell lines, primary cells, complex 3D models, or precision-cut lung slices (PCLS) are used to represent the lung or skin by way of an in vitro barrier model. These models have been applied in toxicity or pharmacological testing. However, contrasting with a clear demand for alternative methods, there is still no widely accepted procedure for cell-based in vitro testing of inhalable substances. In the light of this, an analysis was undertaken of common drawbacks of current approaches. Hence, the pivotal improvements aimed at were the cellular exposure environment, overall performance and applicability, operability of online investigations during exposure and routine setup. It resulted in an improved device (P.R.I.T. ExpoCube) based on an “all-in-one-plate” concept including all phases of the experiment (cell culture, exposure, and read-out) and all experimental groups (two test gas groups, controls) in one single commercial multiwell plate. Verification of the concept was demonstrated in a first experimental series using reference substances (formaldehyde, ozone, and clean air). The resulting ALI procedure enables the application of inhalable substances and mixtures under highly effective exposure conditions in routine utilization. Detlef Ritter and Jan Knebel Copyright © 2014 Detlef Ritter and Jan Knebel. All rights reserved. Differential Effect of Isooctane Doses on HaCaT and HeLa: A Multimodal Analysis Thu, 09 Oct 2014 10:12:11 +0000 A multimodal approach is effective in analyzing biological problems critically and thus also useful in assessing cytotoxicity under chemicals assaults. In this study effects of isooctane, an organic solvent and component of gasoline produced in petroleum industries, have been explored on normal (HaCaT) and cancerous (HeLa) epithelial cells. Besides morphological alterations, impacts on viability, prime molecular expressions, and bioelectrical properties on exposure to different doses of isooctane were noted. Scanning electron microscopy and viability assay demonstrated remarkable structural alterations and cell death, respectively, in HaCaT but not in HeLa. Transcriptomic and immunocytochemical studies on E-cadherin expression also elucidated pronounced toxic effects on HaCaT. Remarkable changes on the bioelectrical properties (e.g., impedance and phase angle) of the HaCaT, in contrast to HeLa, at different temporal points on isooctane exposure also indicated cytotoxic effects in the former. Hence this study illustrated cytotoxicity of isooctane on HaCaT multidimensionally which was evaded by HeLa. Lopamudra Das, Sanmitra Basu, Sanghamitra Sengupta, Soumen Das, and Jyotirmoy Chatterjee Copyright © 2014 Lopamudra Das et al. All rights reserved. Dual Role of Hydrogen Peroxide in Arabidopsis Guard Cells in Response to Sulfur Dioxide Tue, 30 Sep 2014 12:55:55 +0000 Sulfur dioxide (SO2) is a major air pollutant and has significant impacts on plant physiology. Plant can adapt to SO2 stress by controlling stomatal movement, gene expression, and metabolic changes. Here we show clear evidences that SO2-triggered hydrogen peroxide (H2O2) production mediated stomatal closure and cell death in Arabidopsis leaves. High levels of SO2 caused irreversible stomatal closure and decline in guard cell viability, but low levels of SO2 caused reversible stomatal closure. Exogenous antioxidants ascorbic acid (AsA) and catalase (CAT) or Ca2+ antagonists EGTA and LaCl3 blocked SO2-induced stomatal closure and decline in viability. AsA and CAT also blocked SO2-induced H2O2 and elevation. However, EGTA and LaCl3 inhibited SO2-induced increase but did not suppress SO2-induced H2O2 elevation. These results indicate that H2O2 elevation triggered stomatal closure and cell death via signaling in SO2-stimulated Arabidopsis guard cells. NADPH oxidase inhibitor DPI blocked SO2-induced cell death but not the stomatal closure triggered by low levels of SO2, indicating that NADPH oxidase-dependent H2O2 production plays critical role in SO2 toxicity but is not necessary for SO2-induced stomatal closure. Our results suggest that H2O2 production and accumulation in SO2-stimulated plants trigger plant adaptation and toxicity via reactive oxygen species mediating Ca2+ signaling. Huilan Yi, Xin Liu, Min Yi, and Gang Chen Copyright © 2014 Huilan Yi et al. All rights reserved. Compound-Specific Toxicities Detected in CFU-GM, Rat Kidney NRK Cells, Rat Bladder RBLAK Cells, and Rat Liver Slices following Batracylin or N-Acetyl Batracylin Exposure Mon, 08 Sep 2014 00:00:00 +0000 The investigational anticancer agent batracylin (BAT; 8-aminoisoindolo [1,2-b]quinazolin-10(12H)-one; NSC320846) causes γ-H2AX foci development in exposed tumor cells and has demonstrated activity against solid tumors and adriamycin-resistant leukemia. Reports indicate BAT has wide interspecies variation of adverse effects, including myelosuppression, kidney, bladder, and liver damage, including biliary hyperplasia. The effects of BAT and its metabolite N-acetyl batracylin (NAB) were evaluated in the CFU-GM bone marrow toxicity assay, rat kidney (NRK) cells, bladder epithelial (RBLAK) cells, and rat precision cut liver slices (PCLS). Exposure effects were evaluated biochemically and histologically. Human, dog, and rat exhibited similar CFU-GM IC90 values for BAT (21–29 μM). The ATP assay and γ-H2AX staining showed time- and concentration-dependent toxicity in RBLAK (more severe than NRK at <72 hr) NRK and cells ( μM after 96 hr BAT exposure). BAT (5 μM and 25 μM) caused biochemical and histology changes to PCLS by day 3 and 25 μM produced centrilobular hepatotoxicity. NAB (≤5 μM) produced no toxicity in CFU-GM, NRK, or RBLAK cells. However, both BAT and NAB caused biliary epithelial cell proliferation in PCLS. Our studies demonstrated species similarities in sensitivity to BAT-induced myelosuppression, and implicate the metabolite NAB in biliary hyperplasia. Facundo M. Cutuli and Holger P. Behrsing Copyright © 2014 Facundo M. Cutuli and Holger P. Behrsing. All rights reserved. Extraction of Parquat from Blood by Clinoptilolite Tue, 19 Aug 2014 06:38:48 +0000 Paraquat is a bipyridyl herbicide and organic divalent cation which due to its high polarity and water solubility cannot be readily extracted by common organic solvents from body fluids. Dithionite color test for qualitative and quantitative determination of paraquat in urine has been proposed and used for many years. Although some methods were proposed for solvent extraction of paraquat from blood, they are less practical in clinical laboratories and lack high extraction recovery. Clinoptilolite is a highly porous natural zeolite with cation-exchange property and high surface area. In the present work, extraction of paraquat from human blood by clinoptilolite was investigated and compared with Amberlite CG-50 I, a well-known weak cation-exchanger. Blood paraquat was adsorbed by adsorbents (clinoptilolite or Amberlite) and extracted from them by saturated sodium chloride solution. Extracted paraquat was spectrophotometrically measured by means of sodium dithionite reagent at 394.5 nm. Recovery, limit of detection, considering signal-to-noise (S/N) ratio of 3, and limit of quantification, regarding S/N of 10, of paraquat extraction by clinoptilolite and Amberlite CG-50 were 81.7% ± 3.4%, 0.58 μg, and 1.93 μg and 83.6% ± 3.2%, 0.49 μg, and 1.63 μg, respectively. Repeatabilities (within-laboratory error) of paraquat extraction by clinoptilolite and Amberlite CG-50 I were 7.1% and 6.3%, respectively. Mohammad-Amin Aghaii-Afshar and Seyed Vahid Shetab-Boushehri Copyright © 2014 Mohammad-Amin Aghaii-Afshar and Seyed Vahid Shetab-Boushehri. All rights reserved.