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Toxicology and pathology considerations for the design of juvenile animal studies

Abstract

Although exposure to drugs or toxicants can affect children and adults very differently, many compounds lack specific safety information for children. Studies in juvenile animals can help researchers assess pediatric patients' potential response to certain chemicals. Juvenile studies are highly sensitive to animal age, sex and species and must be planned with care to prevent misinterpretation of experimental data. The author reviews considerations for the design of these studies, focusing on toxicological and pathological aspects.

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References

  1. Morford, L.L., Henck, J.W., Breslin, W.J. & DeSesso, J.J. Hazard identification and predictability of children's health risk from animal data. Environ. Health Perspect. 112, 266–271 (2004).

    Article  CAS  Google Scholar 

  2. US Department of Health and Human Services, Food and Drug Administration, Center for Drug Evaluation and Research. Guidance for Industry: Nonclinical Safety Evaluation of Pediatric Drug Products. <[online]> (2006).

  3. Beck, M.J. et al. in Developmental and Reproductive Toxicology (ed. Hood, R.D.) ch. 8 (CRC Taylor & Francis, Boca Raton, 2005).

    Google Scholar 

  4. Messplay, G.C. & Heisey, C. Encouraging pediatric studies. Contract Pharma 2007 (May), 18–20 (2007).

    Google Scholar 

  5. Nunn, T. The current availability of drugs for use in children – issues and solutions. Toxicol. Pathol. 35, 444 (2007).

    Article  Google Scholar 

  6. Landrigan, P., Garg, A. & Droller, D.B.J. Assessing the effects of endocrine disruptors in the National Children's Study. Environ. Health Perspect. 111, 1678–1682 (2003).

    Article  Google Scholar 

  7. Davis-Bruno, K.L. Regulatory perspective – current and upcoming guidelines on juvenile toxicology in the United States. Toxicol. Pathol. 35, 444 (2007).

    Article  Google Scholar 

  8. Baldrick, P. Developing drugs for pediatric use: A role for juvenile animal studies? Regul. Tox. Pharmacol. 39, 381–389 (2004).

    Article  CAS  Google Scholar 

  9. Kacew, S. in General and Applied Toxicology 2nd edn. (eds. Ballantyne, B., Marrs, T & Syverson, T.) 1215–1232 (Nature Publishing Group, London, 1999).

  10. Zoetis, T. & Walls, I. Principles and Practices for Direct Dosing of Pre-weaning Mammals in Toxicity Testing and Research (ILSI, Washington, DC, 2003).

  11. Tyl, R.W. & Marr, M.C. in Developmental and Reproductive Toxicology (ed. Hood, R.D.) ch. 7 (CRC Taylor & Francis, Boca Raton, 2005).

    Google Scholar 

  12. Barr, M. et al. Workshop to identify critical windows of exposure for children's health: cardiovascular and endocrine work group summary. Environ. Health Perspect. 108 (Suppl. 3), 569–571 (2000).

    PubMed  PubMed Central  Google Scholar 

  13. Pryor, J.L., Hughes, C., Foster, W., Hales, B.F. & Robaire, B. Critical windows of exposure for children's health: the reproductive system in animals and humans. Environ. Health Perspect. 108 (Suppl. 3), 491–503 (2000).

    PubMed  PubMed Central  Google Scholar 

  14. Rice, D. & Barone, S. Critical periods of vulnerability for the developing nervous system: evidence from humans and animal models. Environ. Health Perspect. 108 (Suppl. 3), 511–533 (2000).

    PubMed  PubMed Central  Google Scholar 

  15. Pinkerton, K.E. & Joad, J.P. The mammalian respiratory system and critical windows of exposure for children's health. Environ. Health Perspect. 108 (Suppl. 3), 457–462 (2000).

    PubMed  PubMed Central  Google Scholar 

  16. Sawaki, M. et al. Genital tract development in peripubertal female CD IGS rats. Comp. Med. 50, 284–287 (2000).

    CAS  PubMed  Google Scholar 

  17. Birhaum, L.S. Pharmacokinetic basis of age-related changes in sensitivity to toxicants. Ann. Rev. Pharmacol. 31, 101–128 (1991).

    Article  Google Scholar 

  18. Bruckner, J.V. Differences in sensitivity of children and adults to chemical toxicity: The NAS Panel Report. Regul. Tox. Pharmacol. 31, 280–285 (2000).

    Article  CAS  Google Scholar 

  19. Scheuplein, R., Charnley, G. & Dourson, M. Differential sensitivity of children and adults to chemical toxicity I. Biological basis. Regul. Tox. Pharmacol. 35, 429–447 (2002).

    Article  CAS  Google Scholar 

  20. Imaoka, S., Fujita, S. & Funae, Y. Age dependent expression of cytochrome P-450s in rat liver. Biochim. Biophys. Acta. 1097, 187–192 (1991).

    Article  CAS  Google Scholar 

  21. Cresteil, T. Onset of xenobiotic metabolism in children: toxicological implications. Food Addit. Contamin. 15 (Suppl.), 45–51 (1998).

    Article  CAS  Google Scholar 

  22. Hines, R.N. & McCarver, D.B. The ontogeny of human drug-metabolizing enzymes: phase I oxidative enzymes. J. Pharmacol. Exp. Ther. 300, 355–369 (2002).

    Article  CAS  Google Scholar 

  23. Leeder, J.S. Issues in juvenile toxicity: the challenge of developmental drug biotransformation. Toxicol. Pathol. 35, 446 (2007).

    Google Scholar 

  24. Hoet J.J., Ozanne, S. & Reusens, B. Influences of pre- and postnatal nutritional exposures on vascular/endocrine systems in animals. Environ. Health Perspect. 108 (Suppl. 3), 563–568 (2000).

    PubMed  PubMed Central  Google Scholar 

  25. Yildiz, A., Hayirli, A., Okumus, Z., Kaynar, O. & Kisa, F. Physiological profile of juvenile rats: effects of cage size and cage density. Lab Anim. (NY) 36, 28–38 (2007).

    Article  Google Scholar 

  26. Hew, K.W. & Keller, K.A. Postnatal anatomical and functional development of the heart: A species comparison. Birth Defects Res. B Dev. Reprod. Toxicol. 68, 309–320 (2003).

    Article  CAS  Google Scholar 

  27. Walthall, K., Cappon, G.D., Hurtt, M.E. & Zoetis, T. Postnatal development of the gastrointestinal system: a species comparison. Birth Defects Res. B Dev. Reprod. Toxicol. 74, 132–156 (2005).

    Article  CAS  Google Scholar 

  28. Zoetis, T., Tassinari, M.S., Bagi, C., Walthall, K. & Hurtt, M.E. Species comparison of postnatal bone growth and development. Birth Defects Res. B Dev. Reprod. Toxicol. 68, 111–120 (2003).

    Article  CAS  Google Scholar 

  29. Zoetis, T. & Hurtt, M.E. Species comparison of lung development. Birth Defects Res. B Dev. Reprod. Toxicol. 68, 121–124 (2003).

    Article  CAS  Google Scholar 

  30. Holsapple, M.P., West, L.J. & Landreth, K.S. Species comparison of anatomical and functional immune system development. Birth Defects Res. B Dev. Reprod. Toxicol. 68, 321–334 (2003).

    Article  CAS  Google Scholar 

  31. Beckman, D.A. & Feuston, M. Landmarks in the development of the female reproductive system. Birth Defects Res. B Dev. Reprod. Toxicol. 68, 137–143 (2003).

    Article  CAS  Google Scholar 

  32. Marty, M.S., Chapin, R.E., Parks, L.G. & Thorsrud, B.A. Development and maturation of the male reproductive system. Birth Defects Res. B Dev. Reprod. Toxicol. 68, 125–136 (2003).

    Article  CAS  Google Scholar 

  33. Zoetis, T. & Hurtt, M.E. Species comparison of anatomical and functional renal development. Birth Defects Res. B Dev. Reprod. Toxicol. 68, 111–120 (2003).

    Article  CAS  Google Scholar 

  34. Klapwijk, J. Experience of juvenile toxicity studies from a pathologist's perspective – developing drugs for children. Toxicol. Pathol. 35, 445 (2007).

    Google Scholar 

  35. Hall, W.C. et al. Histopathologic observations in weanling B6C3F1 mice and F344/N rats and their adult parental strains. Toxicol. Pathol. 20, 146–154 (1992).

    Article  CAS  Google Scholar 

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Acknowledgements

I thank Kim Ehman of RTI International for her critical review of the manuscript and Ann Marie Hauck for preparation of the manuscript.

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Correspondence to John Curtis Seely.

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The author declares no competing financial interests.

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Seely, J. Toxicology and pathology considerations for the design of juvenile animal studies. Lab Anim 37, 206–209 (2008). https://doi.org/10.1038/laban0508-206

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