Association of the PPAR-γ Gene with Altered Glucose Levels and Psychosis Profile in Schizophrenia Patients Exposed to Antipsychotics.
OBJECTIVE
Metabolic abnormalities, e.g., diabetes, are common among schizophrenia patients. Peroxisome proliferator activated receptor-γ (PPAR-γ) regulates glucose/lipid metabolisms, and schizophrenia like syndrome may be induced by actions involving retinoid X receptor-α/PPAR-γ heterodimers. We examined a possible role of the PPAR-γ gene in metabolic traits and psychosis profile in schizophrenia patients exposed to antipsychotics.


METHODS
Single nucleotide polymorphisms (SNPs) of the PPAR-γ gene and a serial of metabolic traits were determined in 394 schizophrenia patients, among which 372 were rated with Positive and Negative Syndrome Scale (PANSS).


RESULTS
SNP-10, -12, -18, -19, -20 and -26 were associated with glycated hemoglobin (HbA1c) whereas SNP-18, -19, -20 and -26 were associated with fasting plasma glucose (FPG). While SNP-23 was associated with triglycerides, no associations were identified between the other SNPs and lipids. Further haplotype analysis demonstrated an association between the PPAR-γ gene and psychosis profile.


CONCLUSIONS
Our study suggests a role of the PPAR-γ gene in altered glucose levels and psychosis profile in schizophrenia patients exposed to antipsychotics. Although the Pro12Ala at exon B has been concerned an essential variant in the development of obesity, the lack of association of the variant with metabolic traits in this study should not be treated as impossibility or a proof of error because other factors, e.g., genes regulated by PPAR-γ, may have complicated the development of metabolic abnormalities. Whether the PPAR-γ gene modifies the risk of metabolic abnormalities or psychosis, or causes metabolic abnormalities that lead to psychosis, remains to be examined.
Office of Research and Development, Taipei Medical University, Taipei, Taiwan.
Yun-Ru
YR
Liu
Yuli Veterans Hospital, Yuli Township, Hualian County, Taiwan.
Tsung-Ming
TM
Hu
Faculty of Medicine, National Yang Ming University, Taipei, Taiwan. ; Department of Psychiatry, Taichung Veterans General Hospital, Taichung, Taiwan. ; Center for Neuropsychiatric Research, National Health Research Institutes, Miaoli County, Taiwan.
Tsuo-Hung
TH
Lan
Faculty of Medicine, National Yang Ming University, Taipei, Taiwan. ; Chung Hwa University of Medical Technology, Tainan, Taiwan. ; Department of Health Care and Social Work, Yu Da University of Science and Technology, Chao-chiao Township, Miaoli County, Taiwan.
Hsien-Jane
HJ
Chiu
Institute of Public Health and Department of Public Health, National Yang Ming University, Taipei, Taiwan.
Yung-Han
YH
Chang
Department of Health Care and Social Work, Yu Da University of Science and Technology, Chao-chiao Township, Miaoli County, Taiwan. ; Institute of Food Science and Technology, National Taiwan University, Taipei, Taiwan.
Shuo-Fei
SF
Chen
Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.
Yen-Hsin
YH
Yu
Kaohsiung Municipal Kai-Syuan Psychiatric Hospital, Kaohsiung, Taiwan.
Cheng-Chung
CC
Chen
Kaohsiung Municipal Kai-Syuan Psychiatric Hospital, Kaohsiung, Taiwan.
El-Wui
el-W
Loh
Glucose; PPAR-γ gene; Psychosis; Schizophrenia