Objective: Alterations in the serotonergic system were verified to act a role in the pathogenesis of altered neurological and psychiatric diseases. In recent years, Tryptophan (Trp) and serotonin (5-HT) levels have been considered potent biomarkers of diabetes mellitus (DM).
Method: The different Trp metabolism may also play roles in the pathogenesis of DM and mounting risk of complications. The whole blood (WB) 5-HT level was mainly lower among diabetic patients compared to others. That is mostly derived from a lower platelet concentration of 5-HT in these patients.
Results: Indeed, 5-HT level can be considered a potent biomarker for early detection of DM complications. Besides, it was proved that outside the digestive and central nervous systems, 5-HT was discovered in beta cells, and scientists have been attempting to realize its mechanism of action ever since. Towards to end, the determination methods, biomarker's role, and approaches of 5-HT and Trp levels were thoroughly investigated in both healthy and diabetic patients with or without complications. Moreover, the association between insulin and 5-HT has been specifically discussed.
Conclusions: Our study concluded that Trp and 5-HT levels could be exclusively applied for early diagnosis of DM complications as well as many other complications.
Keywords: Biomarker role; Complications; Diabetes mellitus; Insulin; Serotonin; Tryptophan.
© The Author(s), under exclusive licence to Tehran University of Medical Sciences 2022.