Melatonin administration provides relief against neuropathy in diabetes patients: Study

Diabetic neuropathy (DN), a nerve injury, is a common complication of diabetes that compromises a patient's quality of life and casts a significant burden on the healthcare system. Diabetes causes neuropathy by initiating inflammatory pathways, generating toxic free reactive species, and causing histological injury. Nerves in the legs and feet are frequently affected by neuropathy. Despite its widespread prevalent and devastating effects, no treatment exists to prevent its progression. Therefore it is essential to design drugs against DN based on novel therapeutic strategies and targets.

Melatonin (N-acetyl-5-methoxytryptamine) is an endogenous neurohormone produced by the pineal gland and derived from tryptophan. It is a well-known powerful anti-oxidant. The primary mechanism of melatonin is the elimination of free radicals for counteracting neurotoxicity caused by oxidative stress, making it a potent neuroprotective.

Against the above background, Asieh Hosseini, Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran, and colleagues reviewed the potential neuroprotective properties of melatonin against diabetic neuropathy. The study showed that neuropathy is a type of harm that results from diabetes.

For this purpose, the researchers conducted a full systematic search in several electronic databases up to March 2022 under the PRISMA guidelines. Using predefined inclusion and exclusion criteria, forty-seven studies were screened. Finally, nine publications that met the inclusion criteria were included in the systematic review.

The study yielded the following findings:

• According to in vivo findings, melatonin treatment reduces DN by inhibiting oxidative stress and inflammatory pathways.
• Compared to the diabetes groups alone, melatonin treatment exhibited an anti-oxidant trend.
• According to other research, DN also significantly produces biochemical alterations in neuron cells/tissues. Additionally, histological alterations in neuron tissue following DN were detected.

"Our study shows that neuropathy is a type of harm that results from diabetes. Diabetes causes neuropathy by the following mechanisms:- causing histological injury, generating toxic free reactive species, and initiating inflammatory pathways," the researchers wrote.

"The administration of melatonin during diabetic neuropathy reduces neuropathy risk by inhibiting the inflammatory process, reducing oxidative stress, and reducing histological damage," they explained.

"As a result of the study's finding, melatonin treatment may result in a more tolerable neuropathy for patients," they conclude.

Reference:

Hosseini A, Samadi M, Baeeri M, Rahimifard M and Haghi-Aminjan H (2022) The neuroprotective effects of melatonin against diabetic neuropathy: A systematic review of non-clinical studies. Front. Pharmacol. 13:984499. doi: 10.3389/fphar.2022.984499