Vascular Alterations in Mental Disorders: Focus in Angiotensin II Role

Abstract

Mental disorders have high prevalence and long duration, affecting the quality of life and generating elevated economic costs in public health. Approximately 25% of population worldwide will develop any mental illness at some moment of its lifetime. These disorders are the result of complex processes involving the interaction of many pathological changes. Although, each psychiatric disease has well-defined characteristics, some of their neurobiological processes, like inflammation and vascular alterations, seem to be common. Since microvasculature is involved in essential functions as oxygen delivery, waste product removal, and transvascular exchange, any brain vessel alteration could promote a pathological state. In this sense, capillary ultrastructural abnormalities, deficient perfusion, and blood-brain barrier disruption have been described in schizophrenia, depression, and Parkinson?s and Alzheimer?s diseases. These vascular dysfunctions could be related to angiogenic factor deregulations. The abovementioned evidences point out to evaluate the vasculature as a future pharmacological target for the treatment of mental disorders. Among the several factors involved in the regulation of angiogenesis, this chapter will focus on the upstream angiogenic mediator Angiotensin II. This peptide is produced at peripheral and brain level and exerts its principal effects acting through AT1 receptors. Considering that the available treatments for mental illnesses have low efficacy and high incidence of side effects, new pharmacological tools become necessary. The present chapter will be focused in the evidences that support Angiotensin II as a key factor in the understanding and therapy of these pathologies.