Oxidative stress plays a fundamental role in the pathogenesis and progression of type 1 and type 2 diabetes mellitus. In addition, it represents the molecular basis shared by diabetes and other comorbid disorders.

From a neurological point of view, diabetes can be associated with cognitive impairment, represents a risk factor for stroke, and worsens poststroke outcomes. The diabetic changes in the redox status account at least in part for the neurological manifestations of diabetes. In fact, hypo- and hyperglycaemic episodes determine oxidative insults in the brain and cause further damage after brain injury. In addition, oxidative stress is crucially involved in the occurrence of diabetic neuropathy and leads to an accelerated brain aging, thus increasing the risk for neurodegenerative disorders (e.g., Alzheimer’s and Parkinson’s diseases).

From a psychiatric point of view, both behavioural and biochemical aspects explain the link between diabetes and psyche. For example, diabetes and depression share the same risk factors, such as poor diet and physical inactivity, as well as oxidative and nitrosative stress. The gut-brain axis could account for the comorbidity between depression and medical disorders, including diabetes. In addition, if unhealthy dietary habits are frequent among patients suffering from schizophrenia, the latter is characterized by high levels of advanced glycation end products (AGEs) that could favour the occurrence of oxidative stress-related diseases, such as diabetes. On the other hand, psychiatric drugs (antidepressants, antipsychotics, and mood stabilizers) can determine metabolic disturbances, thus favouring the occurrence of diabetes.

In this special issue, we are inviting researchers to contribute with original research articles as well as review articles that seek to address the role of oxidative stress in the occurrence, progression, and management of neuropsychiatric disturbances in diabetes mellitus.

Potential topics include but are not limited to the following:

• Oxidative stress in diabetes and metabolic syndrome
• Oxidative stress and psychiatric drugs-induced metabolic disturbances
• Oxidative stress as a link between diabetes and neurological disorders
• Oxidative stress as a link between diabetes and psychiatric disorders
• Oxidative stress and gut-brain axis