Melatonin is a member of the class of acetamides that is acetamide in which one of the hydrogens attached to the nitrogen atom is replaced by a 2-(5-methoxy-1H-indol-3-yl)ethyl group. It is a hormone secreted by the pineal gland in humans. It has a role as a geroprotector, a hormone, a central nervous system depressant, an anticonvulsant, a radical scavenger, an immunological adjuvant, a mouse metabolite and a human metabolite. It is a member of acetamides and a member of tryptamines. Melatonin, a hormone produced in the brain, is a potent melatonin receptor activator, and possesses important anti-cancer, antioxidative and anti-inflammatory properties, it can reduce lead toxicity in vivo and in vitro. Melatonin may be useful as a pharmacological agent to protect against hepatic metabolic diseases due to its ability to regulate expression of miR-23a.