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Parada-Cruz B, Aztatzi-Aguilar OG, Ramírez-Martínez G, Jacobo-Estrada TL, Cárdenas-González M, Escamilla-Rivera V, Martínez-Olivas MA, Narváez-Morales J, Ávila-Rojas SH, Álvarez-Salas LM, Barbier O. Inflammation- and cancer-related microRNAs in rat renal cortex after subchronic exposure to fluoride. Chem Biol Interact 2023; 379:110519. [PMID: 37121298 DOI: 10.1016/j.cbi.2023.110519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 04/10/2023] [Accepted: 04/27/2023] [Indexed: 05/02/2023]
Abstract
The proximal tubule is a target of subchronic exposure to fluoride (F) in the kidney. Early markers are used to classify kidney damage, stage, and prognosis. MicroRNAs (miRNAs) are small sequences of non-coding single-stranded RNA that regulate gene expression and play an essential role in developing many pathologies, including renal diseases. This study aimed to evaluate the expression of Cytokine-Chemokine molecules (IL-1α/1β/4/6/10, INF-γ, MIP-1α, MCP-1, RANTES, and TGF β1/2/3) and inflammation-related miRNAs to evidence the possible renal mechanisms involved in subchronic exposure to F. Total protein and miRNAs were obtained from the renal cortex of male Wistar rats exposed to 0, 15 and 50 mg NaF/L through drinking water during 40 and 80 days. In addition, cytokines-chemokines were analyzed by multiplexing assay, and a panel of 77 sequences of inflammatory-related miRNAs was analyzed by qPCR. The results show that cytokines-chemokines expression was concentration- and time-dependent with F, where the 50 mg NaF/L were the main altered groups. The miRNAs expression resulted in statistically significant differences in thirty-four miRNAs in the 50 mg NaF/L groups at 40 and 80 days. Furthermore, a molecular interaction network analysis was performed. The relevant pathways modified by subchronic exposure to fluoride were related to extracellular matrix-receptor interaction, Mucin type O-glycan biosynthesis, Gap junction, and miRNAs involved with renal cell carcinoma. Thus, F-induced cytokines-chemokines suggest subchronic inflammation; detecting miRNAs related to cancer and proliferation indicates a transition from renal epithelium to pathologic tissue after fluoride exposure.
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Affiliation(s)
- Benjamín Parada-Cruz
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, CP 07360, Ciudad de México, CDMX, Mexico.
| | - Octavio Gamaliel Aztatzi-Aguilar
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, CP 07360, Ciudad de México, CDMX, Mexico.
| | - Gustavo Ramírez-Martínez
- Departamento de Toxicología y Medicina Ambiental, Laboratorio de inmunología y genética. Inst. Nac. de Enf. Resp, Ismael Cosío Villegas, Calz. de Tlalpan 4502, Belisario Domínguez Secc 16, Tlalpan, 14080, Ciudad de México, CDMX, Mexico.
| | - Tania Libertad Jacobo-Estrada
- Departamento de Biociencias e Ingeniería, Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y Desarrollo, Instituto Politécnico Nacional, 30 de Junio de 1520 s/n, Col. Barrio la Laguna Ticomán, CP 07340, Ciudad de México, CDMX, Mexico.
| | - Mariana Cárdenas-González
- Laboratory of Systems Pharmacology, Harvard Program in Therapeutic Sciences, Harvard Medical School, 200 Longwood Ave, Boston, MA, 02115, USA.
| | - Vicente Escamilla-Rivera
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, CP 07360, Ciudad de México, CDMX, Mexico; Department of Otolaryngology-Head & Neck Surgery, University of Arizona, Tucson, AZ, 85724, USA.
| | - Martha Adriana Martínez-Olivas
- Departamento de Biotecnología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, CP 07360, Ciudad de México, CDMX, Mexico.
| | - Juana Narváez-Morales
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, CP 07360, Ciudad de México, CDMX, Mexico.
| | - Sabino Hazael Ávila-Rojas
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, CP 07360, Ciudad de México, CDMX, Mexico.
| | - Luis Marat Álvarez-Salas
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, CP 07360, Ciudad de México, CDMX, Mexico.
| | - Olivier Barbier
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, CP 07360, Ciudad de México, CDMX, Mexico.
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Saylor C, Malin AJ, Tamayo-Ortiz M, Cantoral A, Amarasiriwardena C, Estrada-Gutierrez G, Tolentino MC, Pantic I, Wright RO, Tellez-Rojo MM, Sanders AP. Early childhood fluoride exposure and preadolescent kidney function. ENVIRONMENTAL RESEARCH 2022; 204:112014. [PMID: 34506780 PMCID: PMC11071127 DOI: 10.1016/j.envres.2021.112014] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 09/01/2021] [Accepted: 09/02/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Early-life renal maturation is susceptible to nephrotoxic environmental chemicals. Given the widespread consumption of fluoride and the global obesity epidemic, our main aim was to determine whether childhood fluoride exposure adversely affects kidney function in preadolescence, and if adiposity status modifies this association. METHODS Our study included 438 children from the PROGRESS cohort. Urinary fluoride (uF) was assessed at age 4 by diffusion analysis; outcomes studied included estimated glomerular filtration rate (eGFR), blood urea nitrogen (BUN), selected kidney proteins and blood pressure measured at age 8-12 years. We modeled the relationship between uF and outcomes, and adjusted for body mass index (BMI), age, sex, and socioeconomic status. RESULTS The median uF concentration was 0.67 μg/mL. We observed null associations between 4-year uF and preadolescent eGFR, although effect estimates were in the expected inverse direction. A single unit increase in ln-transformed uF was associated with a 2.2 mL/min decrease in cystatin C-based eGFR (95% CI: 5.8, 1.4; p = 0.23). We observed no evidence of sex-specific effects or effect modification by BMI status. Although uF was not associated with BMI, among children with obesity, we observed an inverse association (β: 4.8; 95% CI: 10.2, 0.6; p = 0.08) between uF and eGFR. CONCLUSIONS Low-level fluoride exposure in early childhood was not associated with renal function in preadolescence. However, given the adverse outcomes of chronic fluoride consumption it is possible that the preadolescent age was too young to observe any effects. Longitudinal follow-up in this cohort and others is an important next step.
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Affiliation(s)
- Charles Saylor
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Ashley J Malin
- Department of Population and Public Health Sciences, Keck School of Medicine of USC, 2001 N Soto St., Los Angeles, CA, 90032, USA.
| | - Marcela Tamayo-Ortiz
- Occupational Health Research Unit, Mexican Social Security Institute, Mexico City, Mexico.
| | - Alejandra Cantoral
- Iberoamerican University -Mexico City, Department of Health, Mexico City, Mexico
| | - Chitra Amarasiriwardena
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | - Mari Cruz Tolentino
- Department of Nutrition, National Institute of Perinatology, Mexico City, Mexico
| | - Ivan Pantic
- Department of Developmental Neurobiology, National Institute of Perinatology, Mexico City, Mexico
| | - Robert O Wright
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA; Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Martha M Tellez-Rojo
- Occupational Health Research Unit, Mexican Social Security Institute, Mexico City, Mexico
| | - Alison P Sanders
- Department of Environmental and Occupational Health, University of Pittsburgh, USA.
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Johnston NR, Strobel SA. Principles of fluoride toxicity and the cellular response: a review. Arch Toxicol 2020; 94:1051-1069. [PMID: 32152649 PMCID: PMC7230026 DOI: 10.1007/s00204-020-02687-5] [Citation(s) in RCA: 111] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 02/21/2020] [Indexed: 02/04/2023]
Abstract
Fluoride is ubiquitously present throughout the world. It is released from minerals, magmatic gas, and industrial processing, and travels in the atmosphere and water. Exposure to low concentrations of fluoride increases overall oral health. Consequently, many countries add fluoride to their public water supply at 0.7-1.5 ppm. Exposure to high concentrations of fluoride, such as in a laboratory setting often exceeding 100 ppm, results in a wide array of toxicity phenotypes. This includes oxidative stress, organelle damage, and apoptosis in single cells, and skeletal and soft tissue damage in multicellular organisms. The mechanism of fluoride toxicity can be broadly attributed to four mechanisms: inhibition of proteins, organelle disruption, altered pH, and electrolyte imbalance. Recently, there has been renewed concern in the public sector as to whether fluoride is safe at the current exposure levels. In this review, we will focus on the impact of fluoride at the chemical, cellular, and multisystem level, as well as how organisms defend against fluoride. We also address public concerns about fluoride toxicity, including whether fluoride has a significant effect on neurodegeneration, diabetes, and the endocrine system.
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Affiliation(s)
- Nichole R Johnston
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA
| | - Scott A Strobel
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA.
- Department of Chemistry, Yale University, New Haven, CT, 06520, USA.
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Dharmaratne RW. Exploring the role of excess fluoride in chronic kidney disease: A review. Hum Exp Toxicol 2018; 38:269-279. [PMID: 30472891 DOI: 10.1177/0960327118814161] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This review covers nearly 100 years of studies on the toxicity of fluoride on human and animal kidneys. These studies reveal that there are direct adverse effects on the kidneys by excess fluoride, leading to kidney damage and dysfunction. With the exception of the pineal gland, the kidney is exposed to higher concentrations of fluoride than all other soft tissues. Therefore, exposure to higher concentrations of fluoride could contribute to kidney damage, ultimately leading to chronic kidney disease (CKD). Among major adverse effects on the kidneys from excessive consumption of fluoride are immediate effects on the tubular area of the kidneys, inhibiting the tubular reabsorption; changes in urinary ion excretion by the kidneys disruption of collagen biosynthesis in the body, causing damages to the kidneys and other organs; and inhibition of kidney enzymes, affecting the functioning of enzyme pathways. This review proposes that there is a direct correlation between CKD and the consumption of excess amounts of fluoride. Studies particularly show immediate adverse effects on the tubular area of human and animal kidneys leading to CKD due to the consumption of excess fluoride. Therefore, it is very important to conduct more investigations on toxicity studies of excess fluoride on the human kidney, including experiments using human kidney enzymes, to study more in depth the impact of excess fluoride on the human kidney. Further, the interference of excess fluoride on collagen synthesis in human body and its effect on human kidney should also be further investigated.
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Affiliation(s)
- R W Dharmaratne
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, Oxford, MS, USA
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5
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Wang Y, Duan XQ, Zhao ZT, Zhang XY, Wang H, Liu DW, Li GS, Jing L. Fluoride Affects Calcium Homeostasis by Regulating Parathyroid Hormone, PTH-Related Peptide, and Calcium-Sensing Receptor Expression. Biol Trace Elem Res 2015; 165:159-66. [PMID: 25645361 DOI: 10.1007/s12011-015-0245-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 01/18/2015] [Indexed: 10/24/2022]
Abstract
Parathyroid hormone (PTH), PTH-related peptide (PTHrP), and calcium-sensing receptor (CaSR) play important roles in maintaining calcium homeostasis. Here, we study the effect of fluoride on expression of PTH, PTHrP, and CaSR both in vitro and in vivo. MC3T3-E1 cells and Sprague-Dawley rats were treated with different concentrations of fluoride. Then, the free calcium ion concentration in cell culture supernatant and serum were measured by biochemical analyzer. The expression of PTH, PTHrP, and CaSR was analyzed by qRT-PCR and Western blot. We found that the low dose of fluoride increased ionized calcium (i[Ca(2+)]) and the high dose of fluoride decreased i[Ca(2+)] in cell culture supernatant. The low dose of fluoride inhibited the PTH and PTHrP expression in MC3T3-E1 cells. The high dose of fluoride improved the PTHrP expression in MC3T3-E1 cells. Interestingly, we found that NaF decreased serum i[Ca(2+)] in rats. Fluoride increased CaSR expression at both messenger RNA (mRNA) and protein levels in MC3T3-E1 cells and rats. The expression of PTHrP protein was inhibited by fluoride in rats fed regular diet and was increased by fluoride in rats fed low-calcium diet. Fluoride also increased the expression of PTH, NF-kappaB ligand (RANKL), and osteoprotegerin (OPG) in rats. The ratio of RANKL/OPG in rats fed low-calcium food in presence or absence of fluoride was significantly increased. These results indicated that fluoride might be able to affect calcium homeostasis by regulating PTH, PTHrP, and CaSR.
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Affiliation(s)
- Ying Wang
- The First Hospital, Norman Bethune of Jilin University, Changchun, 130041, People's Republic of China
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6
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Perumal E, Paul V, Govindarajan V, Panneerselvam L. A brief review on experimental fluorosis. Toxicol Lett 2013; 223:236-51. [DOI: 10.1016/j.toxlet.2013.09.005] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 09/06/2013] [Accepted: 09/08/2013] [Indexed: 01/17/2023]
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7
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Santoyo-Sanchez MP, del Carmen Silva-Lucero M, Arreola-Mendoza L, Barbier OC. Effects of acute sodium fluoride exposure on kidney function, water homeostasis, and renal handling of calcium and inorganic phosphate. Biol Trace Elem Res 2013; 152:367-72. [PMID: 23400904 DOI: 10.1007/s12011-013-9622-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 01/27/2013] [Indexed: 10/27/2022]
Abstract
Fluoride compounds are abundant and widely distributed in the environment at a variety of concentrations. Further, fluoride induces toxic effects in target organs such as the liver and kidney. In this study, we performed an early analysis of renal function using a clearance technique in Wistar rats acutely exposed to fluoride at a plasma concentration of 0.625 μg/ml. Our results revealed that fluoride, at a concentration close to the concentration present in the serum after environmental exposure, induced a significant tubular dysfunction, resulting in diluted urine, impaired protein reabsorption, and increased calcium and phosphate urinary excretion. Our work demonstrates that even acute exposures to low concentrations of NaF may induce renal damage and confirms that, after exposure, the kidney participates directly in the calcium and phosphate deficiencies observed in fluoride-exposed populations.
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Affiliation(s)
- Mitzi Paola Santoyo-Sanchez
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional CINVESTAV-IPN, Av. IPN No. 2508 Col, San Pedro Zacatenco, Mexico City, CP 07360, Mexico
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8
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Fluorosis caused cellular apoptosis and oxidative stress of rat kidneys. Chem Res Chin Univ 2013. [DOI: 10.1007/s40242-013-2430-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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9
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Chandrajith R, Dissanayake CB, Ariyarathna T, Herath HMJMK, Padmasiri JP. Dose-dependent Na and Ca in fluoride-rich drinking water--another major cause of chronic renal failure in tropical arid regions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2011; 409:671-5. [PMID: 21109289 DOI: 10.1016/j.scitotenv.2010.10.046] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Revised: 10/22/2010] [Accepted: 10/27/2010] [Indexed: 05/09/2023]
Abstract
Endemic occurrence of chronic kidney disease with unknown etiology is reported in certain parts of the north central dry zone of Sri Lanka and has become a new and emerging health issue. The disease exclusively occurs in settlements where groundwater is the main source of drinking water and is more common among low socio-economic groups, particularly among the farming community. Due to its remarkable geographic distribution and histopathological evidence, the disease is believed to be an environmentally induced problem. This paper describes a detailed hydrogeochemical study that has been carried out covering endemic and non-endemic regions. Higher fluoride levels are common in drinking water from both affected and non-affected regions, whereas Ca-bicarbonate type water is more common in the affected regions. In terms of the geochemical composition of drinking water, affected households were rather similar to control regions, but there is a large variation in the Na/Ca ratio within each of the two groups. Fluoride as shown in this study causes renal tubular damage. However it does not act alone and in certain instances it is even cytoprotective. The fine dividing line between cytotoxicity and cytoprotectivity of fluoride appears to be the effect of Ca(2+) and Na(+) of the ingested water on the F(-) metabolism. This study illustrates a third major cause (the other two being hypertension and diabetes) of chronic kidney diseases notably in tropical arid regions such as the dry zone of Sri Lanka.
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Effect of maternal exposure of fluoride on oxidative stress markers and amelioration by selected antioxidants in developing central nervous system of rats. Biologia (Bratisl) 2010. [DOI: 10.2478/s11756-010-0136-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Barbier O, Arreola-Mendoza L, Del Razo LM. Molecular mechanisms of fluoride toxicity. Chem Biol Interact 2010; 188:319-33. [DOI: 10.1016/j.cbi.2010.07.011] [Citation(s) in RCA: 638] [Impact Index Per Article: 45.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2010] [Revised: 07/07/2010] [Accepted: 07/12/2010] [Indexed: 01/27/2023]
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Coplan MJ, Patch SC, Masters RD, Bachman MS. Confirmation of and explanations for elevated blood lead and other disorders in children exposed to water disinfection and fluoridation chemicals. Neurotoxicology 2007; 28:1032-42. [PMID: 17420053 DOI: 10.1016/j.neuro.2007.02.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Revised: 02/01/2007] [Accepted: 02/12/2007] [Indexed: 01/15/2023]
Abstract
Silicofluorides (SiFs), fluosilicic acid (FSA) and sodium fluosilicate (NaFSA), are used to fluoridate over 90% of US fluoridated municipal water supplies. Living in communities with silicofluoride treated water (SiFW) is associated with two neurotoxic effects: (1) Prevalence of children with elevated blood lead (PbB>10microg/dL) is about double that in non-fluoridated communities (Risk Ratio 2, chi2p<0.01). SiFW is associated with serious corrosion of lead-bearing brass plumbing, producing elevated water lead (PbW) at the faucet. New data refute the long-prevailing belief that PbW contributes little to children's blood lead (PbB), it is likely to contribute 50% or more. (2) SiFW has been shown to interfere with cholinergic function. Unlike the fully ionized state of fluoride (F-) in water treated with sodium fluoride (NaFW), the SiF anion, [SiF6]2- in SiFW releases F- in a complicated dissociation process. Small amounts of incompletely dissociated [SiF6]2- or low molecular weight (LMW) silicic acid (SA) oligomers may remain in SiFW. A German PhD study found that SiFW is a more powerful inhibitor of acetylcholinesterase (AChE) than NaFW. It is proposed here that SiFW induces protein mis-folding via a mechanism that would affect polypeptides in general, and explain dental fluorosis, a tooth enamel defect that is not merely "cosmetic" but a "canary in the mine" foretelling other adverse, albeit subtle, health and behavioral effects. Efforts to refute evidence of such effects are analyzed and rebutted. In 1999 and 2000, senior EPA personnel admitted they knew of no health effects studies of SiFs. In 2002 SiFs were nominated for NTP animal testing. In 2006 an NRC Fluoride Study Committee recommended such studies. It is not known at this writing whether any had begun.
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Affiliation(s)
- Myron J Coplan
- Intellequity Technology Services Natick, Massachusetts, United States.
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Xu H, Zhou YL, Zhang JM, Liu H, Jing L, Li GS. Effects of fluoride on the intracellular free Ca2+ and Ca2+-ATPase of kidney. Biol Trace Elem Res 2007; 116:279-88. [PMID: 17709908 DOI: 10.1007/bf02698012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2006] [Revised: 03/14/2006] [Accepted: 04/12/2006] [Indexed: 10/22/2022]
Abstract
In the present study, the effect of fluoride on intracellular free calcium ([Ca2+]i) and Ca2+-ATPase of renal cells were examined. Some paradoxical experimental results about the mechanism of fluoride toxicity were observed. In vivo, 48 Wistar rats were divided into 4 groups, and half of rats were treated with sodium fluoride (NaF) by drinking water (per liter of tap water containing 100 mg F-). Compared with the respective control, the level of [Ca2+]i of the kidney in two fluoride-treated rats obviously increased (p < 0.05); and the activity of Ca2+-ATPase in 100 mg F-/L groups with a standard diet did not significantly increase, and the enzyme activity in 100-mg F-/L group with a low-calcium diet decreased significantly compared to the 100 mg F-/L group with a standard diet (p < 0.05). In vitro, renal tubular cells were cultured and respectively exposed to 1.0, 5.0, 7.5, and 12.5 mg/L fluoride in the culture medium. Results showed the significantly elevated activity of Ca2+-ATPase in the cells exposed to 1.0 and 5.0 mg/L fluoride (p < 0.05), and this enzyme activity indicated inhibitory trend in cells of the 7.5- and 12.5-mg/L fluoride-treated group. To sum up, the effect of fluoride on Ca2+-ATPase is a similar to a dose-effect relationship phenomenon characterized by low-dose stimulation and high-dose inhibition, and the increase of [Ca2+]i probably plays a key role on the mechanism of renal injury in fluorosis.
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Affiliation(s)
- Hui Xu
- Institute of Endemic Diseases, Pharmacy College of Jilin University, Changchun 130021, China
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Balayssac D, Richard D, Authier N, Nicolay A, Jourdan D, Eschalier A, Coudoré F. Absence of painful neuropathy after chronic oral fluoride intake in Sprague-Dawley and Lou/C rats. Neurosci Lett 2002; 327:169-72. [PMID: 12113904 DOI: 10.1016/s0304-3940(02)00421-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The possibility that chronicle oral ingestion of fluoride-rich water could modify peripheral pain sensitivity was studied in two strains of adult rats, Sprague-Dawley and Lou/C rats. Sodium fluoride was given orally in water to male Sprague-Dawley (75 and 150 ppm) and Lou rats (150 ppm) for 15 and 27 weeks, respectively. Using classical behavioural evaluation methods of pain symptoms, only slight tendencies to a thermal hyperalgia and a mechanical allodynia were observed in Sprague-Dawley rats.
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Affiliation(s)
- David Balayssac
- Laboratoire de Toxicologie, INSERM E9904, Faculté de Pharmacie, 28, place Henri Dunant, BP 38, 63001, Clermont-Ferrand Cedex, France
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