title: Levels in neurotransmitter precursor amino acids correlate with mental health in patients with breast cancer.
abstract: Breast cancer is the most common cancer among females. Approximately 30% of cancer patients develop depression or depressive adaptation disorder within 5 years post diagnosis. Low grade inflammation and subsequent changes in neurotransmitter levels could be the pathophysiological link. In the current study we investigated the association of neurotransmitter precursor amino acids with a diagnosis of depression or state anxiety in 154 subjects suffering from breast cancer (BCA(+)), depression (DPR(+)), both or neither. Sociodemographic parameters, severity of depressive symptoms, and state anxiety (ANX) were recorded. Neopterin, kynurenine/tryptophan and phenylalanine/tyrosine were analysed by HPLC or ELISA. Significantly higher serum neopterin values were found in DPR(+) patients (p = 0.034) and in ANX(+) subjects (p = 0.008), as a marker of Th1-related inflammation. The phenylalanine/tyrosine ratio (index of the catecholamine pathway) was associated with the factors "breast cancer" and "depression" and their interaction (all p < 0.001); it was highest in the DPR(+)BCA(+) group. The kynurenine/tryptophan ratio (index of the serotonin pathway) was significantly associated with the factors "breast cancer" and "state anxiety" and their interaction (p < 0.001, p = 0.026, p = 0.02, respectively); it was highest in the ANX(+)BCA(+) group. In BCA(+) patients kynurenine/tryptophan ratios correlated with severity of state anxiety (r = 0.226, p = 0.048, uncorrected) and phenylalanine/tyrosine ratios with severity of depressive symptoms (r = 0.376, p < 0.05, corrected). In conclusion, levels of neurotransmitter precursor amino acids correlate with mental health, an effect which was much more pronounced in BCA(+) patients than in BCA(-) subjects. Aside from identifying underlying pathophysiological mechanisms, these results could be the basis for future treatment studies: in BCA(+) patients with depression the use of serotonin-noradrenaline reuptake inhibitors might be recommended while in those with predominant anxiety selective serotonin reuptake inhibitors might be the treatment of choice.
authors.affiliation: Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Anichstr. 35, 6020 Innsbruck, Austria. Electronic address: katharina.huefner@uki.at.
authors.forename: K
authors.initials: K
authors.lastname: Hüfner
authors.affiliation: Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Anichstr. 35, 6020 Innsbruck, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Oberguggenberger
authors.affiliation: Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Anichstr. 35, 6020 Innsbruck, Austria.
authors.forename: C
authors.initials: C
authors.lastname: Kohl
authors.affiliation: Division of Biological Chemistry, Biocenter, Medical University of Innsbruck, Innsbruck, Austria.
authors.forename: S
authors.initials: S
authors.lastname: Geisler
authors.affiliation: Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Anichstr. 35, 6020 Innsbruck, Austria.
authors.forename: E
authors.initials: E
authors.lastname: Gamper
authors.affiliation: Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Anichstr. 35, 6020 Innsbruck, Austria.
authors.forename: V
authors.initials: V
authors.lastname: Meraner
authors.affiliation: Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Anichstr. 35, 6020 Innsbruck, Austria.
authors.forename: J
authors.initials: J
authors.lastname: Egeter
authors.affiliation: Department of Gynecology and Obstetrics, Medical University of Innsbruck, Innsbruck, Austria.
authors.forename: M
authors.initials: M
authors.lastname: Hubalek
authors.affiliation: Institute of Legal Medicine, Medical University of Innsbruck, Innsbruck, Austria.
authors.forename: B
authors.initials: B
authors.lastname: Beer
authors.affiliation: Division of Biological Chemistry, Biocenter, Medical University of Innsbruck, Innsbruck, Austria.
authors.forename: D
authors.initials: D
authors.lastname: Fuchs
authors.affiliation: Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Anichstr. 35, 6020 Innsbruck, Austria.
authors.forename: B
authors.initials: B
authors.lastname: Sperner-Unterweger
mesh_terms: D000328:Adult; D000368:Aged; D000596:Amino Acids / Q000378:metabolism*; D001008:Anxiety Disorders / Q000378:metabolism / Q000523:psychology; D001943:Breast Neoplasms / Q000378:metabolism* / Q000523:psychology*; D002395:Catecholamines / Q000378:metabolism; D003866:Depressive Disorder / Q000523:psychology; D005260:Female; D006304:Health Status; D006801:Humans; D008603:Mental Health; D053858:Metabolic Networks and Pathways; D008875:Middle Aged; D018377:Neurotransmitter Agents / Q000378:metabolism*; D011569:Psychiatric Status Rating Scales; D012701:Serotonin / Q000378:metabolism; D012959:Socioeconomic Factors; D055815:Young Adult
chemical_list: D000596:Amino Acids; D002395:Catecholamines; D018377:Neurotransmitter Agents; D012701:Serotonin
keywords: Breast cancer; Depression; Kynurenine; Phenylalanine; State anxiety; Tryptophan; Tyrosine