Melatonin (N-acetyl-5-methoxytryptamine), a natural hormone secreted by the pineal gland, the suprachiasmatic nucleus (SNC) and the surrounding tissue, has extensive biological functions, such as antioxidant, anti-inflammatory, antiapoptosis, blocking calcium ion channels and analgesic. In recent years, the research reports that melatonin has certain protective effects on neurological complications induced by metabolic diseases, like diabetes. hTe present review summarizes the research progress the protective effects and ...