Zebrafish as a Model Organism to Study Melatonin Mechanisms and Treatments

Background: Melatonin is an evolutionarily highly conserved molecule. In humans, exogenous melatonin has been shown to entrain circadian rhythms to light dark cycles and act as an antioxidant. Many complex brain disorders, such as autism and Alzheimer's disease, are associated with abnormal melatonin production or melatonin metabolism. Exogenous melatonin may serve as a potential treatment to improve sleeping patterns and delay neuronal deterioration. Objective: Here we review the advantages of using zebrafish to study the pharmacology of exogenous melatonin treatments to rescue endogenous melatonin abnormalities. Method: We perform a literature review to describe the human melatonin system, zebrafish melatonin system, zebrafish advantages as a model organism, and melatonin research using zebrafish. Conclusions: Zebrafish is a model organism for genetics, physiology, chronobiology, gerontology, and pharmacology studies. Future melatonin research can incorporate all of these fields to better understand melatonin mechanisms in wildtype and mutant zebrafish to discover new potential treatments. A standardized treatment method for all developmental stages should be established to encourage interdisciplinary work.