title: Elevated delta-6 desaturase (FADS2) expression in the postmortem prefrontal cortex of schizophrenic patients: relationship with fatty acid composition.
abstract: Although emerging evidence suggests that schizophrenia (SZ) is associated with peripheral and central polyunsaturated fatty acid (PUFA) deficits, there is currently nothing known about the expression of genes that mediate PUFA biosynthesis in SZ patients. Here we determined Delta5 desaturase (FADS1), Delta6 desaturase (FADS2), elongase (HELO1 [ELOVL5]), peroxisomal (PEX19), and Delta9 desaturase (stearoyl-CoA desaturase, SCD) mRNA expression, and relevant fatty acid product:precursor ratios as estimates of enzyme activities, in the postmortem prefrontal cortex (PFC) of patients with SZ (n=20) and non-psychiatric controls (n=20). After correction for multiple comparisons, FADS2 mRNA expression was significantly greater in SZ patients relative to controls (+36%, p=0.002), and there was a positive trend found for FADS1 (+26%, p=0.15). No differences were found for HELO1 (+10%, p=0.44), PEX19 (+12%, p=0.44), or SCD (-6%, p=0.85). Both male (+34%, p=0.02) and female (+42%, p=0.02) SZ patients exhibited greater FADS2 mRNA expression relative to same-gender controls. Drug-free SZ patients (+37%, p=0.02), and SZ patients treated with typical (+40%, p=0.002) or atypical (+31%, p=0.04) antipsychotics, exhibited greater FADS2 mRNA expression relative to controls. Consistent with increased Delta6 desaturase activity, SZ patients exhibited a greater 20:3/18:2 ratio (+20%, p=0.03) and a positive trend was found for 20:4/18:2 (+13%, p=0.07). These data demonstrate abnormal, potentially compensatory, elevations in Delta6 desaturase (FADS2) expression in the PFC of SZ patients that are independent of gender and antipsychotic medications. Greater Delta6 desaturase expression and activity could have implications for central prostaglandin synthesis and proinflammatory signaling.
authors.affiliation: Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH 45267, United States.
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Liu
authors.forename: Ronald
authors.initials: R
authors.lastname: Jandacek
authors.forename: Therese
authors.initials: T
authors.lastname: Rider
authors.forename: Patrick
authors.initials: P
authors.lastname: Tso
authors.forename: Robert K
authors.initials: RK
authors.lastname: McNamara
mesh_terms: D000328:Adult; D000368:Aged; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001344:Autopsy; D000090943:Delta-5 Fatty Acid Desaturase; D044943:Fatty Acid Desaturases / Q000235:genetics / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D006801:Humans; D050602:Linoleoyl-CoA Desaturase / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D017397:Prefrontal Cortex / Q000201:enzymology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012559:Schizophrenia / Q000188:drug therapy / Q000235:genetics* / Q000378:metabolism; D013230:Stearoyl-CoA Desaturase / Q000235:genetics / Q000378:metabolism
chemical_list: D014150:Antipsychotic Agents; D000090943:Delta-5 Fatty Acid Desaturase; D005231:Fatty Acids, Unsaturated; D012333:RNA, Messenger; D044943:Fatty Acid Desaturases; D013230:Stearoyl-CoA Desaturase; C000716847:FADS1 protein, human; C533241:FADS2 protein, human; D050602:Linoleoyl-CoA Desaturase