Preeclampsia is a devastating hypertensive disorder of pregnancy with a high prevalence in the southern regions of the United States. Black pregnant patients are disproportionally at higher risk for preeclampsia onset and severity of disease than other racial groups. The underlying mechanism(s) for this racial disparity are unclear. In our current study we were able to obtain a cohort of patients of self-identifying Black or White race that were overall matched for BMI, blood pressure, gestational and maternal age and parity and we hypothesized that placentas from Black preeclampsia patients would demonstrate elevated preeclampsia-associated placental gene expressions compared to White preeclampsia patients. We collected placenta tissue from both healthy and preeclampsia Black and White patients (n=13-17) who delivered in Augusta, GA, USA. We measured expressions of several preeclampsia-implicated genes, as well as performed placental morphological analysis and bulk RNA sequencing. Contrary to our hypothesis, ddPCR analysis demonstrated that leptin, preproendothelin-1 (PPET-1) endothelial converting enzyme-1 (ECE-1) and soluble FMS-like tyrosine kinase-1 (sFlt-1) were higher in White preeclamptic women than in Black preeclamptic women. Our RNA sequencing analysis revealed that 288 genes differed between healthy Black and preeclamptic Black patients. A striking 2394 gene expressions significantly differed between healthy and preeclampsia White patients. Placental histology analysis revealed that Black preeclampsia patients demonstrated a lower scoring of morphological pathologies associated with preeclampsia compared to White preeclampsia patients. Collectively, these data indicate that gene expressions and placental injury markers associated with preeclampsia are more pronouncedly elevated in White patients compared to Black patients.
Ives et al. (Tue,) studied this question.