Melatonin is responsible for the nocturnal increase observed in serum and thymus of alpha1-thymosin and thymulin concentrations: observations in rats and humans.

Plain Language Summary

This study found that the natural nighttime rise in melatonin levels is responsible for corresponding nocturnal increases in thymosin alpha-1 and thymulin concentrations in both the blood and thymus of rats and humans. The findings reveal an important connection between the circadian hormone melatonin and immune peptide production.