TY - JOUR
T1 - Female-dominant estrogen production in healthy children before adrenarche
AU - Igarashi, Maki
AU - Ayabe, Tadayuki
AU - Yamamoto-Hanada, Kiwako
AU - Matsubara, Keiko
AU - Sasaki, Hatoko
AU - Saito-Abe, Mayako
AU - Sato, Miori
AU - Mise, Nathan
AU - Ikegami, Akihiko
AU - Shimono, Masayuki
AU - Suga, Reiko
AU - Ohga, Shouichi
AU - Sanefuji, Masafumi
AU - Oda, Masako
AU - Mitsubuchi, Hiroshi
AU - Michikawa, Takehiro
AU - Yamazaki, Shin
AU - Nakayama, Shoji
AU - Ohya, Yukihiro
AU - Fukami, Maki
N1 - Funding Information:
The findings and conclusions of this article are solely the responsibility of the authors and do not represent the official views of the aforementioned institute. This study was also supported by a grant from the Japan Society for the Promotion of Science (17H06428).
Funding Information:
This study was funded by the National Institute for Environmental Studies.
Publisher Copyright:
© 2021 The authors Published by Bioscientifica Ltd.
PY - 2021/10
Y1 - 2021/10
N2 - Objective: Ultra-sensitive hormone assays have detected slight sex differences in blood estradiol (E2) levels in young children before adrenarche. However, the origin of circulating E2 in these individuals remains unknown. This study aimed to clarify how E2 is produced in young girls before adrenarche. Design: This is a satellite project of the Japan Environment and Children’s Study organized by the National Institute for Environmental Studies. Methods: We collected blood samples from healthy 6-year-old Japanese children (79 boys and 71 girls). Hormone measurements and data analysis were performed in the National Institute for Environmental Studies and the Medical Support Center of the Japan Environment and Children’s Study, respectively. Results: E2 and follicle stimulating hormone (FSH) levels were significantly higher in girls than in boys, while dehydroepiandrosterone sulfate (DHEA-S) and testosterone levels were comparable between the two groups. Girls showed significantly higher E2/testosterone ratios than boys. In children of both sexes, a correlation was observed between E2 and testosterone levels and between testosterone and DHEA-S levels. Moreover, E2 levels were correlated with FSH levels only in girls. Conclusions: The results indicate that in 6-year-old girls, circulating E2 is produced primarily in the ovary from adrenal steroids through FSH-induced aromatase upregulation. This study provides evidence that female-dominant E2 production starts several months or years before adrenarche. The biological significance of E2 biosynthesis in these young children needs to be clarified in future studies.
AB - Objective: Ultra-sensitive hormone assays have detected slight sex differences in blood estradiol (E2) levels in young children before adrenarche. However, the origin of circulating E2 in these individuals remains unknown. This study aimed to clarify how E2 is produced in young girls before adrenarche. Design: This is a satellite project of the Japan Environment and Children’s Study organized by the National Institute for Environmental Studies. Methods: We collected blood samples from healthy 6-year-old Japanese children (79 boys and 71 girls). Hormone measurements and data analysis were performed in the National Institute for Environmental Studies and the Medical Support Center of the Japan Environment and Children’s Study, respectively. Results: E2 and follicle stimulating hormone (FSH) levels were significantly higher in girls than in boys, while dehydroepiandrosterone sulfate (DHEA-S) and testosterone levels were comparable between the two groups. Girls showed significantly higher E2/testosterone ratios than boys. In children of both sexes, a correlation was observed between E2 and testosterone levels and between testosterone and DHEA-S levels. Moreover, E2 levels were correlated with FSH levels only in girls. Conclusions: The results indicate that in 6-year-old girls, circulating E2 is produced primarily in the ovary from adrenal steroids through FSH-induced aromatase upregulation. This study provides evidence that female-dominant E2 production starts several months or years before adrenarche. The biological significance of E2 biosynthesis in these young children needs to be clarified in future studies.
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U2 - 10.1530/EC-21-0134
DO - 10.1530/EC-21-0134
M3 - Article
AN - SCOPUS:85117606232
VL - 10
SP - 1221
EP - 1226
JO - Endocrine Connections
JF - Endocrine Connections
SN - 2049-3614
IS - 10
ER -
