Abstract

Fluoride, a pollutant present in contaminated ground water, oral care products, food, and pesticides, has deleterious effects in the structure and function of the central nervous system. Among the established neurological defects described in the exposed population, a reduced score in intelligence quotient tests in children of contaminated areas has gained attention over the past years. Maternal fluoride exposure during gestation decreases learning and memory abilities that correlate with a significant diminution of glutamate receptors expression. Since the involvement of glia cells in the maintenance and regulation of glutamatergic synapses is well-documented, in this contribution, we characterized the effect of fluoride exposure in the regulation of glia glutamine transporters. To this end, we used the Müller glia cell line, Mio-M1, and through the use of [3H]L-Glutamine uptake experiments and a Western blot approach, we demonstrate here the functional expression of system N of glutamine transporters, SNAT3 and SNAT5, in this model of human retina radial glia cells. Furthermore, these transporters interact with the glutamate transporter excitatory amino acid transporter 1, in an activity-dependent manner. Fluoride treatment reduces glutamine uptake and cell membrane [3H]glutamine surface binding, in good correlation with a decrease in SNAT3 and 5 protein levels. These results demonstrate that glia cells respond to the presence of fluoride reducing glutamine mobilization and by these means decreases glutamate turnover suggesting a disruption of glutamatergic transmission.

*Original absract online at https://link.springer.com/article/10.1007/s12640-020-00263-4

References

Barbier O, Arreola-Mendoza L, Del Razo LM (2010) Molecular mechanisms of fluoride toxicity. Chem Biol Interact 188:319–333. https://doi.org/10.1016/j.cbi.2010.07.011

CAS  Article  PubMed  Google Scholar

Bartos M, Gumilar F, Gallegos CE, Bras C, Dominguez S, Mónaco N, Esandi MC, Bouzat C, Cancela LM, Minetti A (2018) Alterations in the memory of rat offspring exposed to low levels of fluoride during gestation and lactation: involvement of the ?7 nicotinic receptor and oxidative stress. Reprod Toxicol 81:108–114. https://doi.org/10.1016/j.reprotox.2018.07.078

CAS  Article  PubMed  Google Scholar

Billups D, Marx MC, Mela I, Billups B (2013) Inducible presynaptic glutamine transport supports glutamatergic transmission at the calyx of Held synapse. J Neurosci 33:17429–17434. https://doi.org/10.1523/JNEUROSCI.1466-13.2013

CAS  Article  PubMed  PubMed Central  Google Scholar

Bringmann A, Biedermann B, Faude F, Enzmann V, Reichenbach A (2000) Na(+) currents through Ca(2+) channels in human retinal glial (Müller) cells. Curr Eye Res 20:420–429

CAS  Article  Google Scholar

Bringmann A, Pannicke T, Grosche J et al (2006) Müller cells in the healthy and diseased retina. Prog Retin Eye Res 25:397–424. https://doi.org/10.1016/j.preteyeres.2006.05.003

CAS  Article  PubMed  Google Scholar

Buffo A, Rossi F (2013) Origin, lineage and function of cerebellar glia. Prog Neurobiol 109:42–63

Article  Google Scholar

Chouhan S, Flora SJS (2010) Arsenic and fluoride: two major ground water pollutants. Indian J Exp Biol 48:666–678

CAS  PubMed  Google Scholar

Chouhan S, Lomash V, Flora SJS (2010) Fluoride-induced changes in haem biosynthesis pathway, neurological variables and tissue histopathology of rats. J Appl Toxicol 30:63–73. https://doi.org/10.1002/jat.1474

CAS  Article  PubMed  Google Scholar

Cresto N, Pillet LE, Billuart P, Rouach N (2019) Do astrocytes play a role in intellectual disabilities? Trends Neurosci 42:518–527. https://doi.org/10.1016/j.tins.2019.05.011

CAS  Article  PubMed  Google Scholar

Danbolt NC (2001) Glutamate uptake. Prog Neurobiol 65:1–105

CAS  Article  Google Scholar

Danbolt NCC, Furness DNN, Zhou Y (2016) Neuronal vs glial glutamate uptake: resolving the conundrum

Dienel GA (2019) Brain glucose metabolism: integration of energetics with function. Physiol Rev 99:949–1045. https://doi.org/10.1152/physrev.00062.2017

CAS  Article  PubMed  Google Scholar

Ding Y, YanhuiGao SH et al (2011) The relationships between low levels of urine fluoride on children’s intelligence, dental fluorosis in endemic fluorosis areas in Hulunbuir, Inner Mongolia, China. J Hazard Mater 186:1942–1946. https://doi.org/10.1016/j.jhazmat.2010.12.097

CAS  Article  PubMed  Google Scholar

Flores-Méndez M, Ramírez D, Alamillo N, Hernández-Kelly LC, del Razo LM, Ortega A (2014) Fluoride exposure regulates the elongation phase of protein synthesis in cultured Bergmann glia cells. Toxicol Lett 229:126–133

Article  Google Scholar

Flores-Méndez M, Mendez-Flores OG, Ortega A (2016) Glia plasma membrane transporters: key players in glutamatergic neurotransmission. Neurochem Int 98:46–55

Article  Google Scholar

Gonçalves CA, Rodrigues L, Bobermin LD, Zanotto C, Vizuete A, Quincozes-Santos A, Souza DO, Leite MC (2018) Glycolysis-derived compounds from astrocytes that modulate synaptic communication. Front Neurosci 12. https://doi.org/10.3389/fnins.2018.01035

Grandjean P (2019) Developmental fluoride neurotoxicity: an updated review. Environ Health 18:110. https://doi.org/10.1186/s12940-019-0551-x

Article  PubMed  PubMed Central  Google Scholar

Hertz L, Rothman D (2017) Glutamine-glutamate cycle flux is similar in cultured astrocytes and brain and both glutamate production and oxidation are mainly catalyzed by aspartate aminotransferase. Biology (Basel) 6:17

Google Scholar

Hu YH, Wu SS (1988) Fluoride in cerebrospinal fluid of patients with fluorosis. J Neurol Neurosurg Psychiatry 51:1591–1593. https://doi.org/10.1136/jnnp.51.12.1591

CAS  Article  PubMed  PubMed Central  Google Scholar

Leke R, Schousboe A (2016) The glutamine transporters and their role in the glutamate/GABA-glutamine cycle. In: Advances in neurobiology. Springer, Cham, pp 223–257

Google Scholar

Lutzu S, Castillo PE (2020) Modulation of NMDA receptors by G-protein-coupled receptors: role in synaptic transmission, plasticity and beyond. Neuroscience. https://doi.org/10.1016/j.neuroscience.2020.02.019

Martínez-Lozada Z, Ortega A (2015) Glutamatergic transmission: a matter of three. Neural Plast 2015:1–11

Article  Google Scholar

Martínez-Lozada Z, Guillem AM, Flores-Méndez M, Hernández-Kelly LC, Vela C, Meza E, Zepeda RC, Caba M, Rodríguez A, Ortega A (2013) GLAST/EAAT1-induced glutamine release via SNAT3 in Bergmann glial cells: evidence of a functional and physical coupling. J Neurochem 125:545–554

Article  Google Scholar

Mondal P, Chattopadhyay A (2019) Environmental exposure of arsenic and fluoride and their combined toxicity: a recent update. J Appl Toxicol jat.3931. https://doi.org/10.1002/jat.3931

National Research Council (2006) Fluoride in drinking water: a scientific review of EPA’s standards. The National Academies Press, Washington, DC. https://doi.org/10.17226/11571

Google Scholar

Olivares-Bañuelos TN, Chí-Castañeda D, Ortega A (2019) Glutamate transporters: gene expression regulation and signaling properties. Neuropharmacology 161:107550. https://doi.org/10.1016/j.neuropharm.2019.02.032

CAS  Article  PubMed  Google Scholar

Pellerin L, Magistretti PJ (2012) Sweet sixteen for ANLS. J Cereb Blood Flow Metab 32:1152–1166. https://doi.org/10.1038/jcbfm.2011.149

CAS  Article  PubMed  Google Scholar

Pochini L, Scalise M, Galluccio M, Indiveri C (2014) Membrane transporters for the special amino acid glutamine: structure/function relationships and relevance to human health. Front Chem 11:61

Google Scholar

Reichenbach A, Bringmann A (2013) New functions of Müller cells. Glia 61:651–678. https://doi.org/10.1002/glia.22477

Article  PubMed  Google Scholar

Reichenbach A, Derouiche A, Kirchhoff F (2010) Morphology and dynamics of perisynaptic glia. Brain Res Rev 63:11–25. https://doi.org/10.1016/j.brainresrev.2010.02.003

Article  PubMed  Google Scholar

Rocha-Amador D, Navarro ME, Carrizales L, Morales R, Calderón J (2007) Decreased intelligence in children and exposure to fluoride and arsenic in drinking water. Cad Saude Publica 23:S579–S587. https://doi.org/10.1590/S0102-311X2007001600018

Article  PubMed  Google Scholar

Saeed M, Malik RN, Kamal A (2020) Fluorosis and cognitive development among children (6–14 years of age) in the endemic areas of the world: a review and critical analysis. Environ Sci Pollut Res 27:2566–2579. https://doi.org/10.1007/s11356-019-06938-6

CAS  Article  Google Scholar

Saxena S, Sahay A, Goel P (2012) Effect of fluoride exposure on the intelligence of school children in Madhya Pradesh, India. J Neursci Rural Pract 3: 144 https://doi.org/10.4103/0976-3147.98213

Schneider CA, Rasband WS, Eliceiri KW (2012) NIH image to ImageJ: 25 years of image analysis. Nat Methods 9:671–675

CAS  Article  Google Scholar

Somogyi P, Takagi H, Richards JG, Mohler H (1989) Subcellular localization of benzodiazepine/GABAA receptors in the cerebellum of rat, cat, and monkey using monoclonal antibodies. J Neurosci 9:2197–2209

CAS  Article  Google Scholar

Todd AC, Marx M-C, Hulme SR, Bröer S, Billups B (2017) SNAT3-mediated glutamine transport in perisynaptic astrocytes in situ is regulated by intracellular sodium. Glia 65:900–916

Article  Google Scholar

von Bartheld CS, Bahney J, Herculano-Houzel S (2016) The search for true numbers of neurons and glial cells in the human brain: a review of 150 years of cell counting. J Comp Neurol 524:3865–3895. https://doi.org/10.1002/cne.24040

Article  Google Scholar

Wang SX, Wang ZH, Cheng XT, Li J, Sang ZP, Zhang XD, Han LL, Qiao XY, Wu ZM, Wang ZQ (2007) Arsenic and fluoride expose in drinking water: Children’s IQ and growth in Shanyin Country, Shanxi Province, China. Environ Health Perspect 115:643–647. https://doi.org/10.1289/ehp.9270

CAS  Article  PubMed  PubMed Central  Google Scholar

Yan L, Liu S, Wang C, Wang F, Song Y, Yan N, Xi S, Liu Z, Sun G (2013) JNK and NADPH oxidase involved in fluoride-induced oxidative stress in BV-2 microglia cells. Mediat Inflamm 2013:1–10. https://doi.org/10.1155/2013/895975

CAS  Article  Google Scholar

Yang L, Jin P, Wang X, Zhou Q, Lin X, Xi S (2018) Fluoride activates microglia, secretes inflammatory factors and influences synaptic neuron plasticity in the hippocampus of rats. Neurotoxicology 69:108–120. https://doi.org/10.1016/j.neuro.2018.09.006

CAS  Article  PubMed  Google Scholar

Zhou Y, Danbolt NC (2013) GABA and glutamate transporters in brain. Front Endocrinol (Lausanne) 4:165. https://doi.org/10.3389/fendo.2013.00165–  Article  Google Scholar

Zhou Z, Wang H, Zheng B, Han Z, Chen Y, Ma Y (2017) A rat experimental study of the relationship between fluoride exposure and sensitive biomarkers. Biol Trace Elem Res 180:100–109. https://doi.org/10.1007/s12011-017-0984-4
CAS  Article  PubMed  Google Scholar

Acknowledgments

The technical assistance of Luis Cid and Blanca Ibarra is acknowledged.

Funding

This work was funded by a grant from Consejo Nacional de Ciencia y Tecnología (Conacyt-México) to A.O. (255087). A.L.G.L. was supported by a Conacyt-México fellowship (#455449).