title: Glial cells as key elements in the pathophysiology and treatment of bipolar disorder.
abstract: OBJECTIVE
  The exact pathophysiology of bipolar disorder (BD) is not yet fully understood, and there are many questions in this area which should be answered. This review aims to discuss the roles of glial cells in the pathophysiology of BD and their contribution to the mechanism of action of mood-stabilising drugs.
  
  
  METHODS
  We critically reviewed the most recent advances regarding glial cell roles in the pathophysiology and treatment of BD and the neuroprotective and neurotrophic effects of these cells.
  
  
  RESULTS
  Postmortem studies revealed a decrease in the glial cell number or density in the specific layers of prefrontal and anterior cingulate cortex in the patients with BD, whereas there was no difference in other brain regions, such as entorhinal cortex, amygdala and hippocampus. Astrocytes and oligodendrocytes were the most important glial types that were responsible for the glial reduction, but microglia activation rather than loss may be implicated in BD. The decreased number or density of glial cells may contribute to the pathological changes observed in neurons in the patients with BD. Alteration of specific neurotrophic factors such as glial cell line-derived neurotrophic factor and S100B may be an important feature of BD. Glial cells mediate the therapeutic effects of mood-stabilising agents in the treatment of BD.
  
  
  CONCLUSIONS
  Recent studies provide important evidence on the impairment of glial cells in the pathophysiology and treatment of BD. However, future controlled studies are necessary to elucidate different aspects of glial cells contribution to BD, and the mechanism of action of mood-stabilising drugs.
authors: Shiraz Neuroscience Research Center,Shiraz University of Medical Sciences,Shiraz,Iran.
authors: Mojtaba
authors: M
authors: Keshavarz
mesh_terms: D000679:Amygdala / Q000166:cytology* / Q000378:metabolism / Q000473:pathology; D001253:Astrocytes / Q000378:metabolism / Q000473:pathology; D001714:Bipolar Disorder / Q000188:drug therapy / Q000503:physiopathology*; D001921:Brain / Q000473:pathology / Q000503:physiopathology; D003933:Diagnosis; D051100:Glial Cell Line-Derived Neurotrophic Factor / Q000378:metabolism; D006624:Hippocampus / Q000166:cytology* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D019964:Mood Disorders / Q000188:drug therapy; D009457:Neuroglia / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D009474:Neurons / Q000378:metabolism / Q000473:pathology; D009836:Oligodendroglia / Q000378:metabolism / Q000473:pathology; D064568:S100 Calcium Binding Protein beta Subunit / Q000378:metabolism
chemical_list: C495039:GDNF protein, human; D051100:Glial Cell Line-Derived Neurotrophic Factor; D064568:S100 Calcium Binding Protein beta Subunit; C579160:S100B protein, human
keywords: S100B; bipolar disorder; glial cell line-derived neurotrophic factor; glial cells; mood-stabilising drugs