Angiotensin I converting enzyme gene polymorphisms and risk of psychiatric disorders

Unraveling the role of the renin-angiotensin system in severe mental illnesses: An insight into psychopathology and cognitive deficits

Severe mental illnesses (SMI), especially schizophrenia and bipolar disorder (BD), are associated with significant distress to patients, reduced life expectancy and a higher cost of care. There is growing evidence that SMI may increase the risk of dementia in later life, posing an additional challenge in the management of these patients. SMI present a complex and highly heterogeneous pathophysiology, which has hampered the understanding of its underlying pathological mechanisms and limited the success of the available therapies. Despite the advances in therapeutic approaches in psychiatry over the past decades, treatment resistance is still a common problem in clinical practice, highlighting the urgent need for novel therapeutic targets for SMI. The discovery that renin-angiotensin system (RAS) components are expressed in the central nervous system opened new possibilities for investigating a potential role for this system in the neurobiology of SMI. The safety and efficacy of AT1 receptor blockers and angiotensin-converting enzyme inhibitors in cardiovascular and metabolic diseases, common medical comorbidities among SMI patients and well-known risk factors for dementia, suggest the potential scalability of these strategies for the management of SMI outcomes including the risk of subsequent dementia. This review aimed to discuss the available evidence from animal models and human studies of the potential involvement of RAS in the pathophysiology of SMI. We also provided a reflection on drawbacks and perspectives that can foster the development of new related therapeutic strategies.

Pathophysiological Mechanisms of Psychosis-Induced Atrial Fibrillation: The Links between Mental Disorder and Arrhythmia

Atrial fibrillation (AF) is a common phenomenon of sustained arrhythmia leading to heart failure or stroke. Patients with mental disorders (MD), particularly schizophrenia and bipolar disorder, are at a high risk of AF triggered by the dysregulation of the autonomic nervous system, atrial stretch, oxidative stress, inflammation, and electrical or structural remodeling. Moreover, pathophysiological mechanisms underlying MD may also contribute to the genesis of AF. An overactivated hypothalamic-pituitary-adrenal axis, aberrant renin-angiotensin-aldosterone system, abnormal serotonin signaling, disturbed sleep, and genetic/epigenetic factors can adversely alter atrial electrophysiology and structural substrates, leading to the development of AF. In this review, we provide an update of our collective knowledge of the pathophysiological and molecular mechanisms that link MD and AF. Targeting the pathogenic mechanisms of MD-specific AF may facilitate the development of therapeutics that mitigate AF and cardiovascular mortality in this patient population.

Signaling pathways and genetics of brain Renin angiotensin system in psychiatric disorders: State of the art

Along the conventional pathways, Renin-angiotensin system (RAS) plays a key role in the physiology of the CNS and pathogenesis of psychiatric diseases. RAS is a complex regulatory pathway which is composed of several peptides and receptors and comprises two counter-regulatory axes. The classical (ACE1/AngII/AT1 receptor) axis and the contemporary (ACE2/Ang (1-7)/Mas receptor) axis. The genes coding for elements of both axes have been broadly studied. Numerous functional polymorphisms on components of RAS have been identified to serve as informative disease and treatment markers. This review summarizes the role of each peptide and receptor in the pathophysiology of psychiatric disorders (depression, bipolar disorders and schizophrenia), followed by a concise look at the role of genetic polymorphism of the RAS in the pathophysiology of these disorders.