title: A study of antioxidant activity in patients with schizophrenia taking atypical antipsychotics.
abstract: BACKGROUND
  Atypical antipsychotics have significantly improved the quality of life for schizophrenic patients. Despite their beneficial effects, these antipsychotics induce weight gain, diabetes, and dyslipidemia. The aims of this study were to investigate the antioxidative activity of paraoxonase and assess lipid profile as a cardiovascular risk factor in patients with schizophrenia under long-term clozapine or risperidone treatment.
  
  
  METHODS
  The study included 66 patients with schizophrenia under clozapine or risperidone treatment and 19 healthy control subjects. Serum paraoxonase activities against paraoxon (PON(PO)), phenylacetate (PON(PA)), dihydrocoumarin (PON(DHC)), serum Trolox equivalent antioxidant activity (TEAC), antioxidant gap (GAP), and lipid profile were determined.
  
  
  RESULTS
  PON(DHC) activity was reduced in both antipsychotic drug-treated groups (clozapine 43.46 ± 1.06 U/ml, p < 0.001; risperidone 50.57 ± 1.54 U/ml, p < 0.01; control 52.27 ± 1.34 U/ml). A similar pattern was observed for the PON(DHC)/HDL-cholesterol (HDLC) ratio. On the contrary, PON(PO) and PON(PA) were increased in the treated group, but the corresponding paraoxonase/HDLC ratios were not significantly different from controls, except for PON/HDLC in the clozapine group. TEAC and GAP were only decreased in the clozapine-treated group.
  
  
  CONCLUSIONS
  In patients with schizophrenia, clozapine or risperidone treatment had different effects on various paraoxonase activities. The results of the present study suggest that patients with schizophrenia might be at increased risk for metabolic and cardiovascular disease related to reduced PON(DHC), TEAC, and GAP.
authors.affiliation: Department of Biochemistry, UMF Carol Davila, Bucharest, Romania.
authors.forename: Marilena
authors.initials: M
authors.lastname: Gilca
authors.forename: Gabriela
authors.initials: G
authors.lastname: Piriu
authors.forename: Laura
authors.initials: L
authors.lastname: Gaman
authors.forename: Corina
authors.initials: C
authors.lastname: Delia
authors.forename: Liviu
authors.initials: L
authors.lastname: Iosif
authors.forename: Valeriu
authors.initials: V
authors.lastname: Atanasiu
authors.forename: Irina
authors.initials: I
authors.lastname: Stoian
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D043303:Aryldialkylphosphatase / Q000378:metabolism*; D002318:Cardiovascular Diseases / Q000139:chemically induced / Q000378:metabolism; D003024:Clozapine / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D018967:Risperidone / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D012559:Schizophrenia / Q000188:drug therapy / Q000378:metabolism*; D015430:Weight Gain / Q000187:drug effects
chemical_list: D014150:Antipsychotic Agents; D008055:Lipids; D043303:Aryldialkylphosphatase; D003024:Clozapine; D018967:Risperidone