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Effects of fluoride on metamorphosis, thyroid and skeletal development in Bufo gargarizans tadpoles

Abstract

This study examined the effects of chronic fluoride exposure on metamorphosis, thyroid and skeletal development in tadpoles of Chinese Toad, Bufo gargarizans. The tadpoles were exposed to fluoride concentrations either at 0, 1, 5, 10, or at 50 mg L−1 from Gosner stage 26 to Gosner stage 42. Body weight, total length and percentage of tadpoles reaching metamorphosis climax were recorded, and thyroid histological examinations were employed. In addition, mRNA expression of both deiodinase type 2 (D2) and deiodinase type 3 (D3) was analyzed by using RT-PCR and skeletal systems were investigated by using double-staining methodology at stage 42. Results showed that total length and body weight were unaffected by fluoride exposure at all concentrations while metamorphosis was strongly inhibited only by 50 mg L−1 fluoride. Histomorphological measurements showed the percentage of colloid depletion in thyroid gland increased significantly, while the average diameter of follicles was significantly shorter at 50 mg L−1 concentration. In addition, fluoride at 5 mg L−1 can stimulate bone mineralization, while fluoride at 50 mg L−1 can retard deposition of calcium. In conclusion, our study suggests that 50 mg L−1 fluoride could damage follicular cells in thyroid gland and induce a sharp reduction in thyroid hormone probably through the up-regulation of D3 mRNA expression, and these influences on thyroid system may delay metamorphosis as well as ossification in bone tissue by inhibiting calcium deposition.

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References

  1. Ahmed OM, El-Gareib AW, El-Bakry AM, Abd El-Tawab SM, Ahmed RG (2008) Thyroid hormones states and brain development interactions. Int J Dev Neurosci 26:147–209

    Article  CAS  Google Scholar 

  2. Balch GC, Vélez-Espino LA, Sweet C, Alaee M, Metcalfe CD (2006) Inhibition of metamorphosis in tadpoles of Xenopus laevis exposed to polybrominated diphenyl ethers (PBDEs). Chemosphere 64:328–338

    Article  CAS  Google Scholar 

  3. Barbier O, Arreola-Mendoza L, Del Razo LM (2010) Molecular mechanisms of fluoride toxicity. Chem Biol Interact 188:319–333

    Article  CAS  Google Scholar 

  4. Brande-Lavridsen N, Christensen-Dalsgaard J, Korsgaard B (2010) Effects of ethinylestradiol and the fungicide prochloraz on metamorphosis and thyroid gland morphology in Rana temporaria. Open Zool J 3:7–16

    Article  CAS  Google Scholar 

  5. Brown DD, Cai L (2007) Amphibian metamorphosis. Dev Biol 306:20–33

    Article  CAS  Google Scholar 

  6. Brun LR, Pera LI, Rigalli A (2010) Bone morphometry and differences in bone fluorine containing compounds in rats treated with NaF and MFP. Biomed Pharmacother 64:1–6

    Article  CAS  Google Scholar 

  7. Cai L, Brown DD (2004) Expression of type II iodothyronine deiodinase marks the time that a tissue responds to thyroid hormone-induced metamorphosis in Xenopus laevis. Dev Biol 266:87–95

    Article  CAS  Google Scholar 

  8. Camargo JA (2003) Fluoride toxicity to aquatic organisms: a review. Chemosphere 50:251–264

    Article  Google Scholar 

  9. Croteau MC, Davidson M, Duarte-Guterman P, Wade M, Popesku JT, Wiens S, Lean DR, Trudeau VL (2009) Assessment of thyroid system disruption in Rana pipiens tadpoles chronically exposed to UVB radiation and 4-tert-octylphenol. Aquat Toxicol 95:81–92

    Article  CAS  Google Scholar 

  10. Duellman WE, Trueb L (1994) Biology of amphibians. Johns Hopkins University, Baltimore

    Google Scholar 

  11. Flament S, Kuntz S, Chesnel A, Grillier-Vuissoz I, Tankozic C, Penrad-Mobayed M, Auque G, Shirali P, Schroeder H, Chardard D (2003) Effect of cadmium on gonadogenesis and metamorphosis in Pleurodeles waltl (urodele amphibian). Aquat Toxicol 64:143–153

    Article  CAS  Google Scholar 

  12. Fort DJ, Guiney PD, Weeks JA, Thomas JH, Rogers RL, Noll AM, Spaulding CD (2004) Effect of methoxychlor on various life stages of Xenopus laevis. Toxicol Sci 81:454–466

    Google Scholar 

  13. Gosner KL (1960) A simplified table for staging anuran embryos and larvae with notes on identification. Herpetologica 16:183–190

    Google Scholar 

  14. Helbing CC, Ovaska K, Ji L (2006) Evaluation of the effect of acetochlor on thyroid hormone receptor gene expression in the brain and behavior of Rana catesbeiana tadpoles. Aquat Toxicol 80:42–51

    Article  CAS  Google Scholar 

  15. Hu F, Sharma B, Mukhi S, Patiño R, Carr JA (2006) The colloidal thyroxine (T4) ring as a novel biomarker of perchlorate exposure in the African clawed frog Xenopus laevis. Toxicol Sci 93:268–277

    Article  CAS  Google Scholar 

  16. Huang H, Cai L, Remo BF, Brown DD (2001) Timing of metamorphosis and the onset of the negative feedback loop between the thyroid gland and the pituitary is controlled by type II iodothyronine deiodinase in Xenopus laevis. PNAS 98:7348–7353

    Article  CAS  Google Scholar 

  17. Kaori M, Keiko O (2012) Thyroid hormone-disrupting effects and the amphibian metamorphosis assay. J Toxicol Pathol 25:1–9

    Article  Google Scholar 

  18. Kerney R, Wassersug R, Hall BK (2010) Skeletal advance and arrest in giant non-metamorphosing African clawed frog tadpoles (Xenopus laevis: daudin). J Anat 216:132–143

    Article  Google Scholar 

  19. Kuiper GG, Klootwijk W, Morvan DG, Destree O, Darras VM, Van derGeyten S, Demeneix B, Visser TJ (2006) Characterization of recombinant Xenopus laevis type I iodothyronine deiodinase: substitution of a proline residue in the catalytic center by serine (Pro132Ser) restores sensitivity to 6-propyl-2-thiouracil. Endocrinology 147:3519–3529

    Article  CAS  Google Scholar 

  20. Li W, Zha J, Li Z, Yang L, Wang Z (2009) Effects of exposure to acetochlor on the expression of thyroid hormone related genes in larval and adult rare minnow (Gobiocypris rarus). Aquat Toxicol 94:87–93

    Article  CAS  Google Scholar 

  21. Li W, Zha J, Yang L, Li Z, Wang Z (2011) Regulation of iodothyronine deiodinases and sodium iodide symporter mRNA expression by perchlorate in larvae and adult Chinese rare minnow (Gobiocypris rarus). Mar Pollut Bull 63:350–355

    Article  CAS  Google Scholar 

  22. Mann RM, Hyne RV, Choung CB (2009) Amphibians and agricultural chemicals: review of the risks in a complex environment. Environ Pollut 157:2903–2927

    Article  CAS  Google Scholar 

  23. Mittal M, Flora SJ (2006) Effects of individual and combined exposure to sodium arsenite and sodium fluoride on tissue oxidative stress, arsenic and fluoride levels in male mice. Chem Biol Interact 162:128–139

    Article  CAS  Google Scholar 

  24. Mousny M, Omelon S, Wise L, Everett ET, Dumitriu M, Holmyard DP, Banse X, Devogelaer JP, Grynpas MD (2008) Fluoride effects on bone formation and mineralization are influenced by genetics. Bone 43:1067–1074

    Article  CAS  Google Scholar 

  25. Opitz R, Hartmann S, Blank T (2006) Evaluation of histological and molecular endpoints for enhanced detection of thyroid system disruption in Xenopus laevis tadpoles. Toxicol Sci 90:337–348

    Article  CAS  Google Scholar 

  26. Qin X, Xia X, Yang Z, Yan S, Zhao Y, Wei R, Li Y, Tian M, Zhao X, Qin Z, Xu X (2010) Thyroid disruption by technical decabromodiphenyl ether (DE-83R) at low concentrations in Xenopus laevis. J Environ Sci 22:744–751

    Article  CAS  Google Scholar 

  27. Shi X, Zhuang P, Zhang LZ, Feng GP, Chen LQ, Liu JY, Qu L, Wang RF (2009) The bioaccumulation of fluoride ion (F) in Siberian sturgeon (Acipenser baerii) under laboratory conditions. Chemosphere 75:376–380

    Article  CAS  Google Scholar 

  28. Shivashankara AR, Shivarajachankara YM, Hanumanth RS, Gopalakrishna BP (2000) A clinical and biochemical study of chronic fluoride toxicity in children of Kheru Thanda of Gulbarga district, Karnataka, India. Fluoride 33:66–73

    CAS  Google Scholar 

  29. Shulman JD, Wells LM (1997) Acute fluoride toxicity from ingesting home-use dental products in children, birth to 6 years of age. J Public Health Dent 57:150–158

    Article  CAS  Google Scholar 

  30. Taylor WR, van Dyke GC (1985) Revised procedures for staining and clearing small fishes and other vertebrates for bone and cartilage study. Cybium 9:107–111

    Google Scholar 

  31. Wagner MS, Morimoto R, Dora JM, Benneman A, Pavan R, Maia AL (2003) Hypothyroidism induces type 2 iodothyronine deiodinase expression in mouse heart and testis. J Mol Endocrin 31:541–550

    Article  CAS  Google Scholar 

  32. Wang Z, Brown DD (1993) The thyroid hormone-induced gene expression program for amphibian tail resorption. J Biol Chem 268:16270–16278

    CAS  Google Scholar 

  33. Wang YN, Xiao KQ, Liu JL, Dallner G, Guan ZZ (2000) Effect of long term fluoride exposure on lipid composition in rat liver. Toxicology 146:161–169

    Article  CAS  Google Scholar 

  34. Weinstein LH, Davison AW (2004) Fluorides in the Environment: Effects on Plants and Animals. CABI Publishing, Cambridge

    Book  Google Scholar 

  35. Williams AJ, Robson H, Kester MH, van Leeuwen JP, Shalet SM, Visser TJ, Williams GR (2008) Iodothyronine deiodinase enzyme activities in bone. Bone 43:126–134

    Article  CAS  Google Scholar 

  36. Yan X, Yan X, Morrison A, Han T, Chen Q, Li J, Wang J (2010) Fluoride induces apoptosis and alters collagen I expression in rat osteoblasts. Toxicol Lett 200:133–138

    Article  Google Scholar 

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Acknowledgments

We are grateful to Dr. Gang Wang from University of Kentucky for valuable suggestions and improving scientific writings. The work was supported by National Science Foundation (No. 30200026) and special fund of Shaanxi Normal University (No. GK261001) to H.Y.W. and National Science Foundation (No. 31201726) to H.F.Z.

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The authors declare that they have no conflicts of interest.

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Correspondence to Hongyuan Wang.

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Zhao, H., Chai, L. & Wang, H. Effects of fluoride on metamorphosis, thyroid and skeletal development in Bufo gargarizans tadpoles. Ecotoxicology 22, 1123–1132 (2013). https://doi.org/10.1007/s10646-013-1099-0

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Keywords

  • Metamorphosis
  • Fluoride
  • Thyroid
  • Skeletal development
  • Bufo gargarizans