Prolidase activity and its diagnostic performance in bipolar disorder

J Affect Disord. 2011 Mar;129(1-3):84-6. doi: 10.1016/j.jad.2010.09.003.

Abstract

Objective: Proline has an important role in the brain. Prolidase, a proline splitting enzyme, which is also involved in oxidative stress is not investigated in bipolar disorder (BD).

Methods: 66 BD type I patients and 66 healthy controls were enrolled. Serum prolidase activity was measured in both groups via venous sampling. We have compared patients and controls as well as 3 subgroups of patients (24 euthymic, 22 manic, and 20 depressive patients).

Results: Prolidase activity was significantly higher in patients (p<0.001, t=14.517). There wasn't any significant difference among euthymic, manic and depressives (p=0.305, f=1.211). Positive predictive value was 98.5% and negative predictive value was 92.4% above the cutoff point 502.9375U/L of prolidase activity.

Conclusion: Prolidase activity is impaired in BD, which may be associated with oxidative stress. Prolidase activity may be a trait marker for diagnosing bipolar disorder.

MeSH terms

  • Adult
  • Analysis of Variance
  • Biomarkers / blood
  • Bipolar Disorder / blood
  • Bipolar Disorder / diagnosis
  • Bipolar Disorder / enzymology*
  • Case-Control Studies
  • Chi-Square Distribution
  • Depressive Disorder / blood
  • Depressive Disorder / enzymology
  • Dipeptidases / blood*
  • Female
  • Humans
  • Male
  • ROC Curve

Substances

  • Biomarkers
  • Dipeptidases
  • proline dipeptidase