TITLE:
Regulation of α-Melanocyte-Stimulating Hormone by Testosterone Is Associated with the Onset of Atopic Dermatitis Symptoms during Exercise
AUTHORS:
Kumi Orita, Yurika Yamate, Hiromi Kobayashi, Keiichi Hiramoto
KEYWORDS:
Atopic Dermatitis, α-Melanocyte Stimulating Hormone, Testosterone
JOURNAL NAME:
Journal of Biosciences and Medicines,
Vol.8 No.4,
April
10,
2020
ABSTRACT: Objective: Atopic dermatitis (AD) symptoms are altered with exercise. However, no study has investigated the association between testosterone and AD. The aim of this study was to investigate the role of testosterone by which the strength and weakness of exercise affects the skin symptoms of AD. Methods: Specific pathogen-free (SPF) and conventional NC/Nga mice were used. NC/Nga mice spontaneously developed dermal symptoms similar to AD patients. Two exercises, mild (20 m/min, 60 min) and rigorous (25 m/min, 90 min), were carried out using a treadmill four times every alternate day. Furthermore, we administered testosterone (0, 5, 50, 500, and 5000 pg/mice) to non-exercised conventional NC/Nga mice. On the final day of this experiment, we analyzed the plasma levels of immunoglobulin E (IgE), interleukin (IL)-6, IL-4, IL-13, testosterone and α-melanocyte-stimulating hormone (α-MSH) by ELISA kit. Results: Symptoms manifested by NC/Nga mice were strongly exacerbated upon severe exercise but were ameliorated during mild exercise. Between mild and severe exercised conventional mice, the plasma level of IgE was not changed. On administering an equivalent amount of testosterone, depending on the exercise, AD-like symptoms in non-exercising NC/Nga mice were ameliorated with mild exercise and exacerbated through rigorous exercise. Plasma IL-6, IL-4, and IL-13 levels remained unchanged between +50 pg (mild) and +500 pg (severe) testosterone administration. Plasma α-MSH levels were elevated with +500 pg testosterone but decreased with +50 pg testosterone administration. Conclusion: The present results suggest that exercise largely mimics AD symptoms depending on the α-MSH and testosterone levels.