An increase in normetanephrine in hair follicles of acne lesions through the sympatho‐adrenal medullary system in acne patients with anxiety

Abstract Acne vulgaris, a chronic inflammatory skin disease, has been associated with not only sebaceous gland dysfunction but also various endogenous and exogenous stresses. Since sebaceous glands are under neuroendocrine control, including the hypothalamic–pituitary–adrenal axis and neuro‐autocrine mechanisms, it remains unclear how psychological stress relates to the pathogenesis of acne. In this study, we investigated the relationship between psychological stress and catecholamine in acne lesions from 18 patients with mild or moderate acne. The State‐Trait Anxiety Inventory (STAI) revealed that all patients were anxious, with six having low anxiety and 12 high anxiety. Salivary α‐amylase activity (sAA), which is regulated by the sympatho‐adrenal medullary (SAM) system, positively correlated with the STAI State Anxiety scores (STAI‐S) and was significantly detectable in acne patients with high rather than low anxiety. In addition, the level of normetanephrine, but not metanephrine, both of which are catecholamine metabolites, in hair follicles of acne lesions also positively correlated with the STAI‐S. Furthermore, the normetanephrine level was higher in patients with high rather than low anxiety, whereas there was no change in metanephrine in the hair follicles of the acne lesions. Moreover, neither the sAA nor metanephrine and normetanephrine in the acne lesions was related to acne severity in the patients. Thus, these results provide novel evidence that a SAM system‐associated increase of normetanephrine level in hair follicles is involved in the acne pathology of patients with anxiety.