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International Journal of Primatology

, Volume 39, Issue 2, pp 208–221 | Cite as

Development and Validation of an Enzyme Immunoassay for Fecal Dehydroepiandrosterone Sulfate in Japanese Macaques (Macaca fuscata)

  • Rafaela S. C. Takeshita
  • Fred B. Bercovitch
  • Michael A. Huffman
  • Kodzue Kinoshita
Article

Abstract

Measuring hormonal profiles is important in monitoring stress, physical fitness, and reproductive status in primates. Noninvasive methods have been used to measure several steroid hormones in primates without causing them stress. However, few studies have used feces or urine to measure dehydroepiandrosterone sulfate (DHEAS), an important precursor of sex steroids that has been studied as a biomarker of aging, pregnancy, and stress in humans and nonhuman primates. We developed an enzyme immunoassay to detect DHEAS in the feces of Japanese macaques (Macaca fuscata). Our subjects included eight singly housed Japanese macaques. To validate the assay, we administrated oral DHEA to one male and one female macaque, collected their feces, and measured DHEAS levels over time. Given that DHEAS is related to gonadal steroids and the stress response, we also measured DHEAS concentrations in response to adrenal (adrenocorticotropic hormone [ACTH]) and gonadal (human chorionic gonadotropin [hCG]) stimulation. Our assay successfully detected DHEAS in Japanese macaque feces, and levels of DHEAS were associated with the amount of DHEA ingested. Parallelism and accuracy tests revealed that fecal extracts were reliable measures of DHEAS. Neither ACTH nor hCG challenge appeared to affect DHEAS levels. The method we describe is less expensive than that using the commercially available kits and is applicable to investigations involving aging, stress, and reproduction in Japanese macaques.

Keywords

Aging hormone Fecal steroids Noninvasive monitoring Stress hormones 

Notes

Acknowledgements

We thank Mr. Akihisa Kaneko, Ms. Mayumi Morimoto, and all support staff from the Center for Human Evolution Modeling Research at the Primate Research Institute for providing useful information and assistance during the experimental procedures. We would like to express our gratitude to the journal editor and reviewers for the English language suggestions and for the very useful comments to improve this manuscript. The study was funded by the Primate Research Institute, the Leading Program in Primatology and Wildlife Science (PWS), a grant-in-aid from the Japan Society for the Promotion of Science (JSPS) no. 16 J00399, and a scholarship to R. S. C. Takeshita by the Nippon Foundation.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that there is no conflict of interest regarding the publication of this article.

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Copyright information

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Authors and Affiliations

  • Rafaela S. C. Takeshita
    • 1
  • Fred B. Bercovitch
    • 2
  • Michael A. Huffman
    • 1
  • Kodzue Kinoshita
    • 2
  1. 1.Department of Ecology and Social Behavior, Primate Research InstituteKyoto UniversityInuyamaJapan
  2. 2.Wildlife Research CenterKyoto UniversityKyotoJapan

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