title: GSK3β, CREB, and BDNF in peripheral blood of patients with Alzheimer's disease and depression.
abstract: BACKGROUND
  Glycogen synthase kinase-3β (GSK3β), cAMP-response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) play critical roles in neuronal survival, synaptic plasticity and memory and participate in the pathophysiology of both depressive disorder and Alzheimer's disease (AD).
  
  
  METHODS
  This study was designed to determine the association of GSK3β activity, CREB activity and BDNF concentration in peripheral blood of patients with AD with or without depressive symptoms and in depressive patients without AD. GSK3β activity in platelets, CREB activity in lymphocytes and BDNF concentration in plasma, platelet-rich plasma or platelets were measured in 85 AD patients (36 of whom displayed co-morbid depressive symptoms), 65 non-AD patients with depressive disorder and 96 healthy controls. AD patients were clinically assessed for stage of dementia, cognitive impairment and severity of depressive symptoms. Depressive patients were clinically assessed for severity of depression.
  
  
  RESULTS
  We observed increased CREB activity and GSK3β activity in AD with depressive symptoms or in AD at mild stage of dementia. Decreased BDNF concentration was found in platelet-rich plasma of AD patients at moderate to severe stages of dementia or in AD without depressive symptoms. An association was revealed of the severity of cognitive impairment with the increase of GSK3β in the platelets of AD patients with mild dementia. In depressive patients, a lower concentration of phosphorylated GSK3β was associated with a higher severity of depression. Association was confirmed between severity of depression, CREB activation, and BDNF concentration in drug-naïve depressive patients.
  
  
  CONCLUSIONS
  Our data demonstrated that AD is accompanied by increased CREB activity in lymphocytes and a decreased concentration of BDNF in platelet-rich plasma. The decreased BDNF concentration appears to correlate with moderate to severe stages of dementia in AD. Observation of decreased phosphorylation of GSK3β in platelets of both AD patients with depressive symptoms and depressive patients after treatment confirms the role of increased GSK3β activity in the pathophysiology of both AD and depressive disorder. Associations were confirmed between AD and platelet GSK3β activity, lymphocyte CREB activity and plasma BDNF. CREB activity and platelet BDNF concentration seems to be related to depressive disorder.
authors: Institute of Medical Biochemistry and Laboratory Diagnostics, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Kateřinská 32, 121 08 Prague 2, Czech Republic.
authors: Jan
authors: J
authors: Pláteník
authors: Department of Psychiatry, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 11, 120 00 Prague 2, Czech Republic. Electronic address: zfisar@lf1.cuni.cz.
authors: Zdeněk
authors: Z
authors: Fišar
authors: Institute of Medical Biochemistry and Laboratory Diagnostics, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Kateřinská 32, 121 08 Prague 2, Czech Republic.
authors: Richard
authors: R
authors: Buchal
authors: Department of Psychiatry, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 11, 120 00 Prague 2, Czech Republic.
authors: Roman
authors: R
authors: Jirák
authors: Department of Psychiatry, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 11, 120 00 Prague 2, Czech Republic.
authors: Eva
authors: E
authors: Kitzlerová
authors: Department of Psychiatry, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 11, 120 00 Prague 2, Czech Republic.
authors: Martina
authors: M
authors: Zvěřová
authors: Department of Psychiatry, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 11, 120 00 Prague 2, Czech Republic.
authors: Jiří
authors: J
authors: Raboch
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000097:blood* / Q000150:complications* / Q000523:psychology; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood*; D050882:CREB-Binding Protein / Q000097:blood*; D016022:Case-Control Studies; D003863:Depression / Q000097:blood* / Q000150:complications* / Q000523:psychology; D005260:Female; D038362:Glycogen Synthase Kinase 3 / Q000097:blood*; D000071679:Glycogen Synthase Kinase 3 beta; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D050882:CREB-Binding Protein; C494363:CREBBP protein, human; C000605506:GSK3B protein, human; D000071679:Glycogen Synthase Kinase 3 beta; D038362:Glycogen Synthase Kinase 3
keywords: Alzheimer's disease; BDNF; CREB; Depressive disorder; GSK3β