title: Phoenixin is negatively associated with anxiety in obese men.
abstract: Phoenixin was recently identified in the rat hypothalamus and initially implicated in reproductive functions. A subsequent study described an anxiolytic effect of the peptide. The aim of the study was to investigate a possible association of circulating phoenixin with anxiety in humans. We therefore enrolled 68 inpatients with a broad spectrum of psychometrically measured anxiety (GAD-7). We investigated men since a menstrual cycle dependency of phoenixin has been assumed. Obese subjects were enrolled since they often report psychological comorbidities. In addition, we also assessed depressiveness (PHQ-9) and perceived stress (PSQ-20). Plasma phoenixin levels were measured using a commercial ELISA. First, we validated the ELISA kit performing a spike-and-recovery experiment showing a variance of 6.7±8.8% compared to the expected concentrations over the whole range of concentrations assessed, while a lower variation of 1.6±0.8% was observed in the linear range of the assay (0.07-2.1ng/ml). We detected phoenixin in the circulation of obese men at levels of 0.68±0.50ng/ml. These levels showed a negative association with anxiety scores (r=-0.259, p=0.043), while no additional associations with other psychometric parameters were observed. In summary, phoenixin is present in the human circulation and negatively associated with anxiety in obese men, a population often to report comorbid anxiety.
authors.affiliation: Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine; Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Hofmann
authors.affiliation: Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine; Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Elena
authors.initials: E
authors.lastname: Weibert
authors.affiliation: Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine; Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Ahnis
authors.affiliation: Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine; Charité-Universitätsmedizin Berlin, Berlin, Germany; Charité Center for Internal Medicine with Gastroenterology and Nephrology, Department for Endocrinology, Diabetes and Nutrition, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Ulf
authors.initials: U
authors.lastname: Elbelt
authors.affiliation: Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine; Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Rose
authors.affiliation: Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine; Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Burghard F
authors.initials: BF
authors.lastname: Klapp
authors.affiliation: Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine; Charité-Universitätsmedizin Berlin, Berlin, Germany. Electronic address: andreas.stengel@charite.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Stengel
mesh_terms: D000328:Adult; D000818:Animals; D001007:Anxiety / Q000097:blood / Q000150:complications / Q000188:drug therapy* / Q000473:pathology; D015992:Body Mass Index; D003863:Depression / Q000097:blood / Q000150:complications / Q000188:drug therapy / Q000473:pathology; D006801:Humans; D007028:Hypothalamic Hormones / Q000097:blood*; D007031:Hypothalamus / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000150:complications / Q000188:drug therapy* / Q000473:pathology; D036361:Peptide Hormones / Q000097:blood*; D051381:Rats; D013315:Stress, Psychological
chemical_list: D007028:Hypothalamic Hormones; D036361:Peptide Hormones; C000705635:phoenixin
keywords: Emotion; Gut-brain axis; Psychobiology; Psychoneuroendocrine; Psychosomatic