Melatonin and Exercise Work against Alzheimer's in Mice (image) FECYT - Spanish Foundation for Science and Technology Share Print E-Mail Caption The use of melatonin, a hormone synthesized from the neurotransmitter serotonin, has positive effects which can be used for treating humans. Credit Sarchi Usage Restrictions Creative Commons. Commercial Use Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.