Pharmacological aspects of Citrus aurantium (RUTACEAE) in anxiety disorders

Abstract

Anxiety is a mental disorder of high prevalence, being a topic of attention since the earliest historical records. In Brazil, it affects all life aspects of 9.3% of the population. Conventional treatments, which are most effective, can have adverse effects. Therefore, there is a significant increase in demand for alternative therapies which are less "aggressive" and cheaper, like phytotherapy. Among the numerous plants indicated for the treatment of anxiety, it is worth highlighting Citrus aurantium popularly known as "bitter orange" or "sour orange". Studies show the influence of its essential oils and plant extracts on the central nervous system, especially in the control of anxiety and depression. Although the use of plants, as a form of disease treatment and prevention, is an ancient practice, their indications are often based especially on popular knowledge. Thus, scientific evidence and studies are needed to ensure safety and efficacy in the use of plant species. Thus, the purpose of this study is to investigate the mechanism of action of Citrus aurantium in anxiety disorders. A bibliographical revision was carried out in health scientific databases using the descriptors “Citrus aurantium”, individually and, combined with the following descriptors “anxiety”, “central nervous system”, “mental disorders” and “mechanism of action”. Articles searched based on titles, abstracts, and year of publication (2010-2020), and those that did not address the anxiolytic effect of the species and/or its mechanism of action were excluded. We found 151 articles and considered for the review 16 articles that met the inclusion criteria. Although there are few works that study and prove the anxiolytic effect of Citrus aurantium, the vast majority of them only mention possible mechanisms of action. Analyzing the results reviewed, it was possible to observe that Citrus aurantium acts positively on anxiety, probably, as suggests the studies, through serotonergic pathway.