Fig. 4
From: The role of melatonin in the onset and progression of type 3 diabetes

Melatonin improve cognitive decline by regulating insulin resistance and hyperglycemia. Melatonin controls insulin resistance and glucose metabolism. Melatonin increases the expression of glucose transporters such as Glut1 and Glut2. Also, melatonin increase the secretion of insulin and protects cell damage, and reduces glial reactivity. Finally, melatonin improves cognitive decline in AD brain