title: Inter-relation between brain-derived neurotrophic factor and antioxidant enzymes in bipolar disorder.
abstract: Accumulating evidence indicates that oxidative stress and neurotrophins have a bidirectional relationship. In this post hoc, exploratory analysis, we investigated the association between plasma brain-derived neurotrophic factor (BDNF) levels and activities of the antioxidant enzymes glutathione peroxidase (GPx) and superoxide dismutase (SOD) in individuals with bipolar disorder (BD) and healthy controls.
  
  
  
  We measured plasma levels of BDNF and activities of GPx and SOD in individuals with BD (n=59) and healthy controls (n=26). Information related to current and past psychiatric/medical history, as well as to metabolic comorbidities, was also reported.
  
  
  
  There were negative correlations between BDNF, GPx (r=-.449, P≤.001) and GPx/SOD ratio (r=-.503, P<.001), and a positive correlation between BDNF and SOD (r=.254, P=.020). There was a moderating effect of body mass index (BMI) on the association between BDNF and GPx/SOD rate ratio [(RR)=1.002, P=.034]; interactions between impaired glucose metabolism (IGM), GPx (RR=1.016, P=.033), and GPx/SOD ratio (RR=1.026, P=.002) were also observed. These results were significant in models that included age, gender, alcohol, tobacco and medication use.
  
  
  
  There was a robust and independent correlation between peripheral BDNF and antioxidant enzyme activities in individuals with BD, which was moderated by metabolic comorbidities. These results reinforce the concept that these systems are associated and further extend knowledge of the putative effect of metabolic comorbidities in the pathophysiological substrates of BD.
authors.affiliation: Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil.|Mood Disorders Psychopharmacology Unit (MDPU), University Health Network, University of Toronto, Toronto, Canada.
authors.forename: Rodrigo B
authors.initials: RB
authors.lastname: Mansur
authors.affiliation: Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil.
authors.forename: Camila M
authors.initials: CM
authors.lastname: Santos
authors.affiliation: Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil.|Department of Psychiatry, Clinic for Psychiatry and Psychotherapy, University of Tübingen, Tübingen, Germany.
authors.forename: Lucas B
authors.initials: LB
authors.lastname: Rizzo
authors.affiliation: Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil.
authors.forename: Graccielle R
authors.initials: GR
authors.lastname: Cunha
authors.affiliation: Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil.
authors.forename: Elson
authors.initials: E
authors.lastname: Asevedo
authors.affiliation: Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil.|Vila Maria Outpatient Clinic, São Paulo, Brazil.
authors.forename: Mariane N
authors.initials: MN
authors.lastname: Noto
authors.affiliation: Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil.
authors.forename: Mariana
authors.initials: M
authors.lastname: Pedrini
authors.affiliation: Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil.
authors.forename: Maiara
authors.initials: M
authors.lastname: Zeni
authors.affiliation: Department of Psychiatry, Irmandade da Santa Casa de Misericórdia de São Paulo (ISCMSP), São Paulo, Brazil.
authors.forename: Quirino
authors.initials: Q
authors.lastname: Cordeiro
authors.affiliation: Mood Disorders Psychopharmacology Unit (MDPU), University Health Network, University of Toronto, Toronto, Canada.
authors.forename: Roger S
authors.initials: RS
authors.lastname: McIntyre
authors.affiliation: Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil.
authors.forename: Elisa
authors.initials: E
authors.lastname: Brietzke
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000378:metabolism; D001714:Bipolar Disorder / Q000097:blood / Q000378:metabolism; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood*; D005260:Female; D005979:Glutathione Peroxidase / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000502:physiology*; D013223:Statistics as Topic; D013482:Superoxide Dismutase / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D019208:Brain-Derived Neurotrophic Factor; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase
keywords: bipolar disorder; body mass index; brain-derived neurotrophic factor; diabetes; oxidative stress