Brain Angiotensin II Involvement in Chronic Mental Disorders

Background: The functioning of the central nervous system is complex and it implies tight and coordinated interactions among multiple components. Neurotransmitters systems imbalance is a hallmark in the central nervous system (CNS) disorders. These pathologies profoundly impact the social, cultural, and economic perspective worldwide. The etiopathology of CNS illnesses is still poorly understood, making their treatment difficult. Brain angiotensin II (Ang II), through its AT(1) receptors, modulates dopaminergic, glutamatergic and GABAergic neurotransmission, which are responsible for movement control, cognition, emotions and stress responses. Alterations of these functions, concomitant with modified brain renin-angiotensin system (RAS) components, have been described in CNS pathologies like depression, Parkinson, Alzheimer, and schizophrenia. In this sense, altered functionality of angiotensin I converting enzyme and AT(1) receptors, is associated with augmented susceptibility to the occurrence of these pathologies. Moreover, some epidemiological data showed lower incidence of Alzheimer disease in hypertensive patients under treatment targeting RAS; meanwhile preclinical studies relate RAS with Parkinson and depression. Little is known about schizophrenia and RAS; however, Ang II is closely related to dopamine and glutamate pathways, which are mainly altered in this pathology. Conclusion: The available evidences, together with the results obtained by our group, open the possibility to postulate brain Ang II as a possible therapeutic target to treat the above-mentioned CNS disorders.