Like melatonin, NAS is an agonist at the melatonin receptorsMT1, MT2, and MT3, and may be considered to be a neurotransmitter. In addition, NAS is distributed in some areas of the brain where serotonin and melatonin are not, suggesting that it may have unique central duties of its own instead of merely functioning as a precursor in the synthesis of melatonin. NAS is known to have anti-depressant, neurotrophic and cognition-enhancing effects  and has been proposed to be a target for the treatment of aging-associated cognitive decline and depression 
NAS has been shown to act as a potentTrkB receptor agonist, while serotonin and melatonin do not. Subchronic and chronic administration of NAS to adult mice induces proliferation of neural
progenitor cells (NPC)s, blockage of TrkB abolished this effect suggesting that it is TrkB-dependent. NAS was also found to significantly enhance NPC proliferation in sleep-deprived mice. It is thought that the anti-depressant and neurotrophic effects of NAS are in part due to its role as a TrkB agonist.
NAS acts as a potent antioxidant, NAS effectiveness as an anti-oxidant has been found to be different depending on the experimental model used, it has been described as being between 5 and 20 times more effect than melatonin at protecting against oxidant damage. NAS has been shown to protect against lipid peroxidation in microsomes and mitochondria. NAS has also been reported to lower resting levels of ROS in peripheral blood lymphocytes and to exhibit anti-oxidant effects against t-butylated hydroperoxide- and diamide-induced ROS. NAS has also been observed to inhibit nitric oxide synthase.
^Zhao H, Poon AM, Pang SF (March 2000). "Pharmacological characterization, molecular subtyping, and autoradiographic localization of putative melatonin receptors in uterine endometrium of estrous rats". Life Sciences. 66 (17): 1581–91. doi:10.1016/S0024-3205(00)00478-1. PMID11261588.
^Gavazza MB.; Català A. (2004). "Protective effect of N-acetyl-serotonin on the nonenzymatic lipid peroxidation in rat testicular microsomes and mitochondria". J. Pineal Res. 37 (3): 153–60. doi:10.1111/j.1600-079x.2004.00150.x. PMID15357659.
^Wölfler A.; Abuja PM.; Schauenstein K.; Liebmann PM. (1999). "N-acetylserotonin is a better extra- and intracellular antioxidant than melatonin". FEBS Lett. 449 (2–3): 206–10. doi:10.1016/s0014-5793(99)00435-4. PMID10338133.