Relationship of Placental and Serum Lipoprotein-Associated Phospholipase A2 Levels with Hypertensive Disorders of Pregnancy

BACKGROUND: A series of studies has shown that lipoprotein-associated phospholipase A2 (Lp-PLA2) is closely associated with abnormal lipid metabolism and vascular endothelial cell injury, but its role in hypertensive disorders of pregnancy (HDP) remains unclear. This study aims to determine the relationship between placental and serum LP-PLA2 levels and HDP, and to provide a feasible method for predicting HDP. METHODS: The placental and serum Lp-PLA2 levels of 63 patients with HDP (20, 25, and 18 cases with gestational hypertension, mild preeclampsia, and severe preeclampsia, respectively) and 20 women with normal pregnancies (control group) were measured via a combination of tissue microarray and immunohistochemistry, real-time quantitative RT-PCR and enzyme-linked immunosorbent assay (ELISA). RESULTS: 1) The gene and protein expression levels of placental LP-PLA2: the HDP group had significantly higher levels than those of the control group (P < 0.05). The mild preeclampsia group had significantly higher levels than those of the control group (P < 0.05); the severe preeclampsia group had significantly higher levels than those of the mild preeclampsia group (P < 0.05). 2) Serum levels of Lp-PLA2: the HDP group had significantly higher levels than those of the control group (P < 0.05). The Lp-PLA2 levels increased gradually with the progression of the HDP; there were significant differences in the four groups using pair-wise comparisons (P < 0.05). 3) Serum levels of LP-PLA2 were positively correlated with placental LP-PLA2 levels in the HDP group (r = 0.435, P < 0.05). CONCLUSION: Elevated Lp-PLA2 levels may be associated with the occurrence of HDP, and changes of Lp-PLA2 levels in the maternal blood may be regarded as a monitoring indicator for this disease.