This paper investigates the production melatonin in the gut, notably it being unrelated to the day/light cycle and how eating patterns affect its production, and what the produced melatonin may be used for.
Key takeaways
The Gut is one of the leading sources of melatonin production in the body
Light has now impact on amount of melatonin produced in the gut
Increasing Tryptophan intake increases production
L-Tryptophan => Serotonin => Melatonin
Once produced, it stays in gut or enters circulation
In gut melatonin has paracrine, autocrine or luminal actions
Paracrine: a cell targets a nearby cell
Autocrine: a cell targets itself, releasing a signal that can bind to receptors on its own surface.
Luminal: acting on interior of cell
In circulation melatonin has endocrine action
Endocrine: the hormone is distributed in blood and binds to distant target cells