title: Early-life stress and antidepressants modulate peripheral biomarkers in a gene-environment rat model of depression.
abstract: BACKGROUND
  Availability of peripheral biomarkers for depression could aid diagnosis and help to predict treatment response. The objective of this work was to analyse the peripheral biomarker response in a gene-environment interaction model of depression. Genetically selected Flinders Sensitive Line (FSL) rats were subjected to maternal separation (MS), since early-life trauma is an important antecedent of depression. An open-ended approach based on a proteomic analysis of serum was combined with the evaluation of depression-associated proteins.
  
  
  METHODS
  Rats experienced MS and chronically received escitalopram (ESC) or nortryptiline (NOR). Serum proteins were compared by two-dimensional gel electrophoresis. Corticosterone, cytokines, BDNF and C-reactive protein (CRP) were measured by immunoassays.
  
  
  RESULTS
  Comparing FSL with the control Flinders Resistant Line (FRL), Apo-AI and Apo-AIV, alpha1-macroglobulin, glutathione peroxidase and complement-C3 were significantly modulated. Significant increases were detected in leptin, interleukin (IL) 1alpha and BDNF. CRP levels were significantly reduced. The impact of early-life stress was assessed by comparing FSL+MS versus FSL. Apo-E, alpha1-macroglobulin, complement-C3, transferrin and hemopexin were significantly modulated. The effect of stress in antidepressant response was then evaluated. In the comparison FSL+ESC+MS versus FSL+ESC, albumin, alpha1-macroglobulin, glutathione peroxidase and complement-C3 were modulated and significant reductions were detected in IL4, IL6, IL10, CRP and BDNF. By comparing FSL+NOR+MS versus FSL+NOR proteins like Apo-AIV, pyruvate dehydrogenase, alpha1-macroglobulin, transferrin and complement-C3 showed different levels.
  
  
  CONCLUSIONS
  Lipid metabolism and immunity proteins were differently expressed in FSL in comparison with FRL. Exposure to MS induced changes in inflammation and transport proteins which became apparent in response to antidepressant treatments. Modulated proteins could suggest biomarker studies in humans.
authors.affiliation: Neurosciences CEDD, GlaxoSmithKline, Verona, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Carboni
authors.forename: Serena
authors.initials: S
authors.lastname: Becchi
authors.forename: Chiara
authors.initials: C
authors.lastname: Piubelli
authors.forename: Alessandra
authors.initials: A
authors.lastname: Mallei
authors.forename: Roberto
authors.initials: R
authors.lastname: Giambelli
authors.forename: Maria
authors.initials: M
authors.lastname: Razzoli
authors.forename: Aleksander A
authors.initials: AA
authors.lastname: Mathé
authors.forename: Maurizio
authors.initials: M
authors.lastname: Popoli
authors.forename: Enrico
authors.initials: E
authors.lastname: Domenici
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism; D015283:Citalopram / Q000494:pharmacology*; D003345:Corticosterone / Q000097:blood; D016207:Cytokines / Q000097:blood; D003866:Depressive Disorder / Q000188:drug therapy / Q000378:metabolism* / Q000523:psychology; D004195:Disease Models, Animal; D015180:Electrophoresis, Gel, Two-Dimensional; D004797:Enzyme-Linked Immunosorbent Assay; D007118:Immunoassay; D008426:Maternal Deprivation; D009661:Nortriptyline / Q000494:pharmacology*; D040901:Proteomics; D051381:Rats; D013315:Stress, Psychological / Q000378:metabolism* / Q000523:psychology
chemical_list: D015415:Biomarkers; D019208:Brain-Derived Neurotrophic Factor; D016207:Cytokines; D015283:Citalopram; D002097:C-Reactive Protein; D009661:Nortriptyline; D003345:Corticosterone