Melatonin, an ancient ally against pancreatic disorders

Melatonin is mainly produced in the pineal gland of mammals with a circadian rhythm. It has also been synthesized in different organs and tissues including the gastrointestinal tract. Additionally, melatonin is widely present in plants and foodstuff. In addition to its effects on the sleep-wake cycle and reproductive regulation in photoperiodic animals, melatonin regulates a wide variety of cellular processes, participating in the control of antioxidant defenses, immune response, energy metabolism, cell growth and proliferation, having beneficial effects on most of the tissues and organs, including the pancreas. Here, we have reviewed the recent findings related to the effects of melatonin on the physiology of the exocrine pancreas. Of major relevance, the effects of the indoleamine on pathological processes such as cancer, inflammation, diabetes, and fibrosis are also reviewed. Not less important, its effects on normal/healthy cells of the pancreas to modulate normal physiological functions are discussed.