Association between polymorphism in Cyclophilin A gene and its serum and placental expression in Han Chinese women with severe preeclampsia

Abstract

Objectives: Cyclophilin A (CypA) plays important roles in inflammation and oxidative stress and is significantly increased in serum of preeclampsia (PE) patients. We aimed to investigate CypA genetic polymorphism and its serum and placenta expressions in severe PE of Han Chinese women.

Methods: A case-control study of 82 severe PE patients and 179 healthy pregnancies was conducted. Single-nucleotide polymorphism (SNP) sites of rs3735481, rs9638978 and rs11984372 were analyzed by TaqMan assay. CypA serum levels were determined by enzyme-linked immunosorbent assay (ELISA). CypA mRNA levels and protein expressions in placentas were assessed by quantitative real-time polymerase chain reaction (PCR), western blot, and immunofluorescence assay, respectively.

Results: There were significantly lower frequency of rs3735481 allele C (odds ratio (OR): 0.60, 95% confidence interval (CI): 0.36-0.98; p = .04), and significantly higher frequency of rs9638978 allele A in severe PE especially in early onset PE patients (OR: 2.23, 95% CI: 1.35-3.71, p = .002). Frequency of rs9638978 AA genotype was significantly higher in early onset PE (p < .001). CypA serum levels were significantly higher in severe PE especially in early onset PE (p < .001). Meanwhile, CypA serum levels were significantly lower in carriers with the AC genotype of rs3735481 (p = .019) and significantly higher in carriers with the AA genotype of rs9638978 (p = .017). CypA mRNA levels and protein expressions were found to be significantly increased in PE placentas (both p < .01).

Conclusions: The CypA genetic polymorphisms of rs3735481 and rs9638978 may be associated with severe PE, and rs9638978 AA genotype may be associated with an increasing risk of early onset severe PE in Han Chinese women. High CypA levels in serum and placenta may contribute to the pathogenesis of severe PE. Our results may provide a new clue for the etiology of severe PE.

Keywords: Cyclophilin A; PPIA gene; Placenta; Severe preeclampsia; Single nucleotide polymorphism.