Serum calcium-independent phospholipase A2 activity in bipolar affective disorder

Bipolar Disord. 2006 Jun;8(3):265-70. doi: 10.1111/j.1399-5618.2006.00299.x.


Objective: Phospholipases A2 (PLA2) are a family of enzymes involved in membrane phospholipid metabolism and cell signalling. The gene encoding one form, type VI calcium-independent phospholipase A2, is located in a region of DNA that may contain a gene important in the aetiology of psychosis. Moreover, the activity of calcium-independent PLA2 is reported to be elevated in the blood and brain of patients with schizophrenia. In this study we determined whether a similar change takes place in patients with bipolar disorder with and without a history of psychosis.

Methods: Serum calcium-independent and -dependent PLA2 activities were determined in 24 patients with bipolar I disorder.

Results: Serum calcium-independent and -dependent PLA2 activities in bipolar cases did not differ significantly from that in healthy volunteers (HVs). However, calcium-independent PLA2 activity was significantly (p < 0.05) higher in patients with a history of psychosis compared with those with no history of psychosis (by 55%) or to HVs (by 31%).

Conclusions: Our data suggest that a subset of bipolar I disorder patients with a history of psychosis have elevated calcium-independent PLA2 activity. Given that this enzyme activity is also increased in schizophrenia, elevated rates of phospholipid turnover mediated by the enzyme could represent a common biochemical feature of psychotic illness.

MeSH terms

  • Adult
  • Bipolar Disorder / blood*
  • Calcium / blood*
  • Cell Membrane / metabolism
  • Female
  • Humans
  • Male
  • Phospholipases A / blood*
  • Phospholipases A2
  • Phospholipids / metabolism
  • Signal Transduction / physiology


  • Phospholipids
  • Phospholipases A
  • Phospholipases A2
  • Calcium