- Email: [email protected]
Repeated administration of benzophenone induced oxidative stress in alterations of morphometry and cytomembrane morphology of rat red blood cell
Abstracts / Toxicology Letters 259S (2016) S73–S247
PP14.6 Repeated administration of benzophenone induced oxidative stress in alterations of morphometry and cytomembrane morphology of rat red blood cell Uma Dutta Department of Zoology, Cotton College, Cotton College State University, Guwahati, Assam 781001, India Introduction: Application of varieties of sunguards during daylight hours has been clinically accepted. Among these, benzophenone (BZ) is the most commonly used primary intermediate for the preparation of sunscreen and many other cosmetic products in the market. Millions of people are exposed to this chemical on a daily basis either occupationally or as consumers and has become a public health concern. Objective: To evaluate the possible oxidative stress effect on the erythrocyte of albino rat exposed repeatedly to single sublethal dose (15 mg/ml/kg body wt. daily) for a period of 17 weeks. Materials and methods: The assessment was based on changes in morphometric measurement of cell size and cytomembrane morphology at LM, AFM, SEM level along with anti-oxidant enzyme activities following standard methods. Results: The findings of the investigation showed a significant increase in total erythrocyte population and alteration of RBC related indices (p < 0.05). Morphometric evaluation of representative shape and size parameters of erythrocyte cells viz. perimeter, area and its ratio, solidity, roundness, width and height were significantly (p < 0.05) changed in BZ treated group as compared to normal ones. Qualitative morphological analysis of RBC’s cytomembrane both at LM and SEM level revealed striking changes on the surface topography and membrane abnormalities of RBC in the peripheral circulation. The degree of erythrocyte membrane response was reflected prominently by the appearance of teardrop, echinocytic, leptocytic, stomatocytic transformation with discocyte asymmetry. The values of membrane roughness (both arithmetic average and root mean square) by AFM were also significantly increased (p < 0.05). Total GSH content of erythrocyte and antioxidant enzyme activities – CAT, GSH-Px decreased significantly (p < 0.01) with significant increase of SOD activities in treated rats. Conclusions: The result of the study concluded that BZ is a potent agent of oxidative stress causing damage to membrane of erythrocyte and causes gross haematological disturbances. The morphometric assay of RBC definitely suggests the haematotoxic nature of BZ. Financial support: Partial support, UGC, Govt. of India. http://dx.doi.org/10.1016/j.toxlet.2016.07.366 P15: Metabolism/ Biotransformation/ Polymorphism PO15.1 The HepaRG cell line: A valuable model for biotransformation and metabolomic studies N.J. Cabaton, M.H. Meireles, C. Canlet, M. Tremblay-Franco, E.L. Jamin, L. Dolo, A. Hillenweck, D. Zalko Toxalim, Université de Toulouse, INRA, Toulouse, France Introduction: Humans are exposed to a variety of man-made chemicals. Some of it can be bioactivated through biotransformation processes. The need to reduce the number of animals used for toxicity studies implies the development of reliable in vitro tools,
S155
which should reflect as closely as possible the human in vivo situation. In parallel, novel approaches in the field of metabolomics are being developed to highlight metabolic changes in biological systems exposed to chemicals. Ideally, in vitro models should express the largest possible metabolic capabilities, both regarding xenobiotics metabolism (biotransformation) and general metabolism (global approaches, metabolomics). Objective: We performed metabolic profiling studies to examine the metabolic pathways and biotransformation rates of a variety of food and environmental contaminants such as bisphenols (BPA, BPF), phthtalate (DEHP), and polycyclic aromatic hydrocarbons (Fluoranthene, Benz[a]pyrene). Metabolomic approaches were investigated based on exposed/control HepaRG cells extracts, in the context of low concentration exposure (as low as 10−12 M). Methods: Concentration ranges were optimized for each contaminant and metabolic profiling was performed on differentiated HepaRG cells using radio-HPLC following a 24-h exposure. Metabolomics: sample extracts were submitted to 1 H NMR spectroscopy and NMR data were analyzed by multivariate statistical methods. Results: The HepaRG cell line expresses high metabolic capabilities, like human primary hepatocytes, with the advantage of having the indefinite growth capacity of hepatic cell lines. Metabolomics were able to discriminate between the control group and all BPA-exposed groups, with the discriminant metabolites suggesting a disruption in energetic and lipid metabolism pathways. Conclusions: Taken together, our data demonstrate that the HepaRG cell line is an extremely valuable model for toxicological studies, taking into account phase I as well as phase II biotransformations, but also highly suitable for the study of subtle metabolic shifts, highlighted by metabolomic approaches. http://dx.doi.org/10.1016/j.toxlet.2016.07.368 PO15.2 Polymorphisms in glutathione (GSH-) related genes and their impact on mercury nephrotoxicity O. Flórez-Vargas 1 , L.H. Sánchez Rodríguez 1,2 1 Laboratory of Environmental Toxicology and Toxicogenomics, Group of Immunology and Molecular Epidemiology, Faculty of Health, Industrial University of Santander, Bucaramanga, Colombia 2 School of Microbiology, Industrial University of Santander, Bucaramanga, Colombia
Introduction: The kidneys are one of the main target organs for elemental mercury. Nevertheless, our previous findings found no meaningful relationship between Hg concentrations and the frequency of altered kidney function monitoring parameters in active artisanal gold miners. Several factors might have directly or indirectly influenced our findings, among them, genetic factors are considered one of the most plausible. In this context, polymorphisms in glutathione (GSH-) related genes may modify the toxicity of Hg as GSH plays a central role in Hg metabolism via conjugation, which results in differences on Hg retention. Objective: To investigate whether functional SNP in genes of GSH metabolism are associated with Hg concentrations and renal dysfunction biomarkers in people exposed to Hg due to artisanal gold mining activities. Materials and methods: The study enrolled 164 miners and 127 participant controls. The Hg concentrations were measured in blood and urine by atomic absorption spectrometry. The glomerular filtration rate (eGFR) was calculated by using the
PP14.6 Repeated administration of benzophenone induced oxidative stress in alterations of morphometry and cytomembrane morphology of rat red blood cell Uma Dutta Department of Zoology, Cotton College, Cotton College State University, Guwahati, Assam 781001, India Introduction: Application of varieties of sunguards during daylight hours has been clinically accepted. Among these, benzophenone (BZ) is the most commonly used primary intermediate for the preparation of sunscreen and many other cosmetic products in the market. Millions of people are exposed to this chemical on a daily basis either occupationally or as consumers and has become a public health concern. Objective: To evaluate the possible oxidative stress effect on the erythrocyte of albino rat exposed repeatedly to single sublethal dose (15 mg/ml/kg body wt. daily) for a period of 17 weeks. Materials and methods: The assessment was based on changes in morphometric measurement of cell size and cytomembrane morphology at LM, AFM, SEM level along with anti-oxidant enzyme activities following standard methods. Results: The findings of the investigation showed a significant increase in total erythrocyte population and alteration of RBC related indices (p < 0.05). Morphometric evaluation of representative shape and size parameters of erythrocyte cells viz. perimeter, area and its ratio, solidity, roundness, width and height were significantly (p < 0.05) changed in BZ treated group as compared to normal ones. Qualitative morphological analysis of RBC’s cytomembrane both at LM and SEM level revealed striking changes on the surface topography and membrane abnormalities of RBC in the peripheral circulation. The degree of erythrocyte membrane response was reflected prominently by the appearance of teardrop, echinocytic, leptocytic, stomatocytic transformation with discocyte asymmetry. The values of membrane roughness (both arithmetic average and root mean square) by AFM were also significantly increased (p < 0.05). Total GSH content of erythrocyte and antioxidant enzyme activities – CAT, GSH-Px decreased significantly (p < 0.01) with significant increase of SOD activities in treated rats. Conclusions: The result of the study concluded that BZ is a potent agent of oxidative stress causing damage to membrane of erythrocyte and causes gross haematological disturbances. The morphometric assay of RBC definitely suggests the haematotoxic nature of BZ. Financial support: Partial support, UGC, Govt. of India. http://dx.doi.org/10.1016/j.toxlet.2016.07.366 P15: Metabolism/ Biotransformation/ Polymorphism PO15.1 The HepaRG cell line: A valuable model for biotransformation and metabolomic studies N.J. Cabaton, M.H. Meireles, C. Canlet, M. Tremblay-Franco, E.L. Jamin, L. Dolo, A. Hillenweck, D. Zalko Toxalim, Université de Toulouse, INRA, Toulouse, France Introduction: Humans are exposed to a variety of man-made chemicals. Some of it can be bioactivated through biotransformation processes. The need to reduce the number of animals used for toxicity studies implies the development of reliable in vitro tools,
S155
which should reflect as closely as possible the human in vivo situation. In parallel, novel approaches in the field of metabolomics are being developed to highlight metabolic changes in biological systems exposed to chemicals. Ideally, in vitro models should express the largest possible metabolic capabilities, both regarding xenobiotics metabolism (biotransformation) and general metabolism (global approaches, metabolomics). Objective: We performed metabolic profiling studies to examine the metabolic pathways and biotransformation rates of a variety of food and environmental contaminants such as bisphenols (BPA, BPF), phthtalate (DEHP), and polycyclic aromatic hydrocarbons (Fluoranthene, Benz[a]pyrene). Metabolomic approaches were investigated based on exposed/control HepaRG cells extracts, in the context of low concentration exposure (as low as 10−12 M). Methods: Concentration ranges were optimized for each contaminant and metabolic profiling was performed on differentiated HepaRG cells using radio-HPLC following a 24-h exposure. Metabolomics: sample extracts were submitted to 1 H NMR spectroscopy and NMR data were analyzed by multivariate statistical methods. Results: The HepaRG cell line expresses high metabolic capabilities, like human primary hepatocytes, with the advantage of having the indefinite growth capacity of hepatic cell lines. Metabolomics were able to discriminate between the control group and all BPA-exposed groups, with the discriminant metabolites suggesting a disruption in energetic and lipid metabolism pathways. Conclusions: Taken together, our data demonstrate that the HepaRG cell line is an extremely valuable model for toxicological studies, taking into account phase I as well as phase II biotransformations, but also highly suitable for the study of subtle metabolic shifts, highlighted by metabolomic approaches. http://dx.doi.org/10.1016/j.toxlet.2016.07.368 PO15.2 Polymorphisms in glutathione (GSH-) related genes and their impact on mercury nephrotoxicity O. Flórez-Vargas 1 , L.H. Sánchez Rodríguez 1,2 1 Laboratory of Environmental Toxicology and Toxicogenomics, Group of Immunology and Molecular Epidemiology, Faculty of Health, Industrial University of Santander, Bucaramanga, Colombia 2 School of Microbiology, Industrial University of Santander, Bucaramanga, Colombia
Introduction: The kidneys are one of the main target organs for elemental mercury. Nevertheless, our previous findings found no meaningful relationship between Hg concentrations and the frequency of altered kidney function monitoring parameters in active artisanal gold miners. Several factors might have directly or indirectly influenced our findings, among them, genetic factors are considered one of the most plausible. In this context, polymorphisms in glutathione (GSH-) related genes may modify the toxicity of Hg as GSH plays a central role in Hg metabolism via conjugation, which results in differences on Hg retention. Objective: To investigate whether functional SNP in genes of GSH metabolism are associated with Hg concentrations and renal dysfunction biomarkers in people exposed to Hg due to artisanal gold mining activities. Materials and methods: The study enrolled 164 miners and 127 participant controls. The Hg concentrations were measured in blood and urine by atomic absorption spectrometry. The glomerular filtration rate (eGFR) was calculated by using the