Measurement of the Estradiol Concentration in Cerebrospinal Fluid from Infants and Its Correlation with Serum Estradiol and Exosomal MicroRNA-126-5p

Estradiol has an important role in the brain, such as in neuronal development and protection, but estradiol levels in the human brain have not been well investigated. In this study, we measured the estradiol concentration in the cerebrospinal fluid (CSF) of infants to reveal the relationships between the estradiol concentrations in the serum and the CSF and further determined exosomal microRNAs in serum. Estradiol in the CSF was strongly correlated with serum estradiol and moderately correlated with miR-126-5p in the serum exosomes. This report is the first to determine the estradiol concentration in CSF from infants and showed that the levels of miR-126-5p as well as serum estradiol can be candidates to predict brain estrogen status.