Methyl Mercury Uptake Across Bovine Brain Capillary Endothelial Cells in Vitro: The Role of Amino Acids
Abstract
Abstract: Previous studies in the rat in vivo have demonstrated that co‐injection of methyl mercury (MeHg) with L‐cysteine into the common carotid artery enhances brain Hg levels following a single capillary pass through the CNS vasculature. In order to elucidate the relationship between MeHg transport and the neutral amino acid transport carrier system, regulatory aspects of MeHg transport across the bovine blood‐brain barrier were investigated in isolated brain microvessel preparations. Following 1 hour co‐incubations of 203Hg‐MeHgCl with 0.1 mM L‐cysteine at 37°, 203Hg uptake by suspended microvessels was significantly increased (P<0.05) compared with controls. This enhanced capillary uptake of 203Hg was abolished by co‐incubations of microvessels with 0.1 mM L‐cysteine‐L‐methionine, or 0.1 mM L‐cysteine plus AT‐125 (alpha S, 5S)‐alpha‐amino‐3‐chloro‐4,5‐dihydro‐5‐isoxazolacetic acid), an irreversible inhibitor of gammaglutamyl‐transpeptidase. One hr co‐incubations of bovine capillaries with 203Hg‐MeHgCl and 0.1 mM D‐cysteine at 37° or 0.1 mM L‐cysteine at 0° did not increase rat of 203Hg uptake compared with controls. These results indicate that L‐cysteine enhances the rate of capillary MeHg uptake. The accumulation of 203Hg in the bovine microvessels appears to be a carrier‐mediated process. It is inhibited by L‐methionine, a competitive substrate for neutral amino acid transport, and by AT‐125. Capillary uptake of 203Hg is stereospecific to the L‐enantiomorph of cysteine, suggesting selective uptake of MeHg across the blold‐brain barrier. The data emphasize the relationship between the L‐enantiomorph neutral amino acid carrier system and MeHg transport across the capillaries.
Number of times cited: 43
- Mainak Banerjee and Gouriprasanna Roy, Cleavage of Hg–C Bonds of Organomercurials Induced by Im OH Se via Two Distinct Pathways , Inorganic Chemistry, 10.1021/acs.inorgchem.7b01301, 56, 21, (12739-12750), (2017).
- Christy C. Bridges and Rudolfs K. Zalups, Mechanisms involved in the transport of mercuric ions in target tissues, Archives of Toxicology, 91, 1, (63), (2017).
- Han Wang, Beibei Chen, Man He, Xiaoxiao Yu and Bin Hu, Selenocystine against methyl mercury cytotoxicity in HepG2 cells, Scientific Reports, 10.1038/s41598-017-00231-7, 7, 1, (2017).
- Eva M. Krupp, Zuzana Gajdosechova, Tanja Schwerdtle and Hanna Lohren, Mercury Toxicity and Speciation Analysis, Metallomics, (285-304), (2016).
- Yasuhiro Ishihara, Takuya Takemoto, Atsuhiko Ishida and Takeshi Yamazaki, Protective Actions of 17β-Estradiol and Progesterone on Oxidative Neuronal Injury Induced by Organometallic Compounds, Oxidative Medicine and Cellular Longevity, 2015, (1), (2015).
- Maths Berlin, Rudolfs K. Zalups and Bruce A. Fowler, Mercury, Handbook on the Toxicology of Metals, 10.1016/B978-0-444-59453-2.00046-9, (1013-1075), (2015).
- Takuya Takemoto, Yasuhiro Ishihara, Atsuhiko Ishida and Takeshi Yamazaki, Neuroprotection elicited by nerve growth factor and brain-derived neurotrophic factor released from astrocytes in response to methylmercury, Environmental Toxicology and Pharmacology, 40, 1, (199), (2015).
- Hanna Lohren, Julia Bornhorst, Hans-Joachim Galla and Tanja Schwerdtle, The blood–cerebrospinal fluid barrier – first evidence for an active transport of organic mercury compounds out of the brain, Metallomics, 7, 10, (1420), (2015).
- Nicholas Ralston, Alexander Azenkeng, Carla Ralston, J III and Laura Raymond, Selenium-Health Benefit Values as Seafood Safety Criteria, Seafood Science, 10.1201/b17402-20, (433-457), (2014).
- Marta Vázquez, Dinoraz Vélez and Vicenta Devesa, In Vitro Characterization of the Intestinal Absorption of Methylmercury using a Caco-2 Cell Model, Chemical Research in Toxicology, 27, 2, (254), (2014).
- Luciana T. Zimmermann, Danúbia B. dos Santos, Dirleise Colle, Alessandra A. dos Santos, Mariana A. Hort, Solange C. Garcia, Lucas Paines Bressan, Denise Bohrer and Marcelo Farina, Methionine Stimulates Motor Impairment And Cerebellar Mercury Deposition in Methylmercury-Exposed Mice, Journal of Toxicology and Environmental Health, Part A, 77, 1-3, (46), (2014).
- Luciana T. Zimmermann, Danúbia B. Santos, Aline A. Naime, Rodrigo B. Leal, José G. Dórea, Fernando Barbosa, Michael Aschner, João Batista T. Rocha and Marcelo Farina, Comparative study on methyl- and ethylmercury-induced toxicity in C6 glioma cells and the potential role of LAT-1 in mediating mercurial-thiol complexes uptake, NeuroToxicology, 38, (1), (2013).
- Christy C. Bridges, Lucy Joshee and Rudolfs K. Zalups, Placental and fetal disposition of mercuric ions in rats exposed to methylmercury: Role of Mrp2, Reproductive Toxicology, 34, 4, (628), (2012).
- Stephanie J. B. Fretham, Samuel Caito, Ebany J. Martinez-Finley and Michael Aschner, Mechanisms and modifiers of methylmercury-induced neurotoxicity, Toxicology Research, 10.1039/c2tx20010d, 1, 1, (32), (2012).
- Rudolfs K. Zalups and Christy C. Bridges, Relationships between the Renal Handling of DMPS and DMSA and the Renal Handling of Mercury, Chemical Research in Toxicology, 25, 9, (1825), (2012).
- Feiyue Wang, Marcos Lemes and Mohammad A. K. Khan, Metallomics of Mercury: Role of Thiol‐ and Selenol‐Containing Biomolecules, Environmental Chemistry and Toxicology of Mercury, (517-544), (2011).
- Christy C. Bridges and Rudolfs K. Zalups, Transport of Inorganic Mercury and Methylmercury in Target Tissues and Organs, Journal of Toxicology and Environmental Health, Part B, 13, 5, (385), (2010).
- Nicholas V.C. Ralston and Laura J. Raymond, Dietary selenium's protective effects against methylmercury toxicity, Toxicology, 278, 1, (112), (2010).
- Daniel Henrique Roos, Robson Luiz Puntel, Thiago Henrique Lugokenski, Rafael Porto Ineu, Denise Bohrer, Marilise E. Burger, Jeferson L. Franco, Marcelo Farina, Michael Aschner, João Batista T. Rocha and Nilda B. De Vargas Barbosa, Complex Methylmercury–Cysteine Alters Mercury Accumulation in Different Tissues of Mice, Basic & Clinical Pharmacology & Toxicology, 107, 4, (789-792), (2010).
- Christy Bridges and Rudolfs Zalups, Ionic and Molecular Mimicry and the Transport of Metals, Cellular and Molecular Biology of Metals, 10.1201/9781420059984-c10, (241-294), (2010).
- Rudolfs Zalups and Christy Bridges, Molecular and Cellular Biology of Mercury in the Kidneys, Cellular and Molecular Biology of Metals, 10.1201/9781420059984-c2, (35-77), (2010).
- Masatake Fujimura, Fusako Usuki, Masumi Sawada and Akihiko Takashima, Methylmercury induces neuropathological changes with tau hyperphosphorylation mainly through the activation of the c-jun-N-terminal kinase pathway in the cerebral cortex, but not in the hippocampus of the mouse brain, NeuroToxicology, 30, 6, (1000), (2009).
- Ingrid Heggland, Parvinder Kaur and Tore Syversen, Uptake and efflux of methylmercury in vitro: Comparison of transport mechanisms in C6, B35 and RBE4 cells, Toxicology in Vitro, 10.1016/j.tiv.2009.06.018, 23, 6, (1020-1027), (2009).
- Mohammad A. K. Khan, Abu Md. Asaduzzaman, Georg Schreckenbach and Feiyue Wang, Synthesis, characterization and structures of methylmercury complexes with selenoamino acids, Dalton Transactions, 29, (5766), (2009).
- Nicholas V.C. Ralston, Carla R. Ralston, J. Lloyd Blackwell and Laura J. Raymond, Dietary and tissue selenium in relation to methylmercury toxicity, NeuroToxicology, 29, 5, (802), (2008).
- Nicholas V. C. Ralston, Selenium Health Benefit Values as Seafood Safety Criteria, EcoHealth, 5, 4, (442), (2008).
- Zhaobao Yin, Haiyan Jiang, Tore Syversen, João B. T. Rocha, Marcelo Farina and Michael Aschner, The methylmercury‐l‐cysteine conjugate is a substrate for the L‐type large neutral amino acid transporter, Journal of Neurochemistry, 107, 4, (1083-1090), (2008).
- Jack C. Clifton, Mercury Exposure and Public Health, Pediatric Clinics of North America, 54, 2, (237.e1), (2007).
- MATHS BERLIN, RUDOLFS K. ZALUPS and BRUCE A. FOWLER, Mercury, Handbook on the Toxicology of Metals, 10.1016/B978-012369413-3/50088-4, (675-729), (2007).
- Ann Marie Reardon and Hari K. Bhat, Methylmercury neurotoxicity: Role of oxidative stress, Toxicological & Environmental Chemistry, 89, 3, (535), (2007).
- Tatsumi Adachi, Characteristic Effects of L-Methionine on Tissue Distribution of Methylmercury in Mice, JOURNAL OF HEALTH SCIENCE, 52, 2, (174), (2006).
- Robert A. Yokel, Stephen M. Lasley and David C. Dorman, The Speciation of Metals in Mammals Influences Their Toxicokinetics and Toxicodynamics and Therefore Human Health Risk Assessment1, Journal of Toxicology and Environmental Health, Part B, 9, 1, (63), (2006).
- Joseph A. Caruso, Rodolfo G. Wuilloud, Jorgelina C. Altamirano and Wesley R. Harris, Modeling and Separation–Detection Methods to Evaluate the Speciation of Metals for Toxicity Assessment, Journal of Toxicology and Environmental Health, Part B, 10.1080/15287390500196172, 9, 1, (41-61), (2006).
- Christy C. Bridges and Rudolfs K. Zalups, Molecular and ionic mimicry and the transport of toxic metals, Toxicology and Applied Pharmacology, 204, 3, (274), (2005).
- Rudolfs K Zalups and Sarfaraz Ahmad, Molecular handling of cadmium in transporting epithelia, Toxicology and Applied Pharmacology, 186, 3, (163), (2003).
- Gouri Shanker, Jeffrey W Allen, Lysette A Mutkus and Michael Aschner, Methylmercury inhibits cysteine uptake in cultured primary astrocytes, but not in neurons, Brain Research, 914, 1-2, (159), (2001).
- Jørgen Drasbáek Schiønning, Experimental neurotoxicity of mercury Autometallographic and stereologic studies on rat dorsal root ganglion and spinal cord, APMIS, 108, S99, (5-32), (2011).
- Yasuo Oyama, Yuko Yamazaki, Yoshihiko Okada, Kazuo Takahama, Masaya Satoh and Hiromi Hayashi, Toxicity of methylmercury conjugated with l-cysteine on rat thymocytes and human leukemia K562 cells in comparison with that of methylmercury chloride, Environmental Toxicology and Pharmacology, 9, 1-2, (49), (2000).
- Michael Aschner, Blood–Brain Barrier: Physiological and Functional Considerations, Handbook of Developmental Neurotoxicology, 10.1016/B978-012648860-9.50024-8, (339-351), (1998).
- Yasuo Oyama, Mami Nakata, Mineshi Sakamoto, Lumi Chikahisa, Norikazu Miyoshi and Masaya Satoh, Methylmercury toxicity in dissociated rat brain neurons: modification by l-cysteine and trimethylbenzylmercaptan and comparison with dimethylmercury and N-ethylmaleimide, Environmental Toxicology and Pharmacology, 6, 4, (221), (1998).
- Jiro Fujiyama, Kimiko Hirayama and Akira Yasutake, Mechanism of methylmercury efflux from cultured astrocytes, Biochemical Pharmacology, 47, 9, (1525), (1994).
- Jørgen Drasbæk Schiønning and Bjarne Møller-Madsen, Autometallographic detection of mercury in rat spinal cord after treatment with organic mercury, Virchows Archiv B Cell Pathology Including Molecular Pathology, 61, 1, (307), (1992).
- Michael Aschner and Judy Lynn Aschner, Mercury neurotoxicity: Mechanisms of blood-brain barrier transport, Neuroscience & Biobehavioral Reviews, 14, 2, (169), (1990).




