Expression of the gene coading for PGC-1α in peripheral blood leukocytes and related gene variants in patients with Parkinson's disease

Introduction: Peroxisome proliferator-activated receptor (PPAR)-gamma coactivator-1 alpha (PGC-1 alpha) plays an important role in Parkinson's disease (PD). The aim of the study was to evaluate PGC-1 alpha gene expression in the peripheral blood of PD patients. We also investigated PGC-1 alpha-related gene variants and identified whether they are associated with PGC-1 alpha gene expression. Methods: 259 PD patients and 253 healthy controls were included in this study. PPARGC1A (the gene encoding PGC-1 alpha) expression levels were tested using real-time PCR. Single nucleotide polymorphisms (SNPs) of the PGC-1 alpha-related genes (PPARGC1A, PPARG and SIRTI) were genotyped by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Results: PPARGC1A levels were significantly decreased in PD patients (P = 0.000) and negatively correlated with the patients' H&Y stage (r = -0.212, P = 0.039) and UPDRS-III score (r = -0.208, P = 0.044), after correcting, these correlations disappeared. The genotype frequencies of PGC-1 alpha-related gene variants were not associated with the risk of PD. PPARGC1A rs2970870 variant was associated with the NMS score (P = 0.026), SIRTI rs7895833 variant was associated with HAMA score (P = 0.029). PPARG rs4684847 variant was associated with MMSE score (P = 0.031). PPARG rs1801282, rs4684847, rs3856806 variants were associated with MoCA score. After correcting, only the association between PPARG rs4684847 and MoCA score remained significant (FDR= 0.048). PGC-1 alpha-related gene variants had no effect on PGC-1 alpha gene expression. Conclusion: The decreased expression of PGC-1 alpha may not be due to its related gene variants. PGC-1 alpha could become a candidate blood-based biomarker for diagnosis and monitoring disease progression. (C) 2018 Elsevier Ltd. All rights reserved.