Placental lipid droplet composition: Effect of a lifestyle intervention (UPBEAT) in obese pregnant women

Abstract

Maternal obesity is associated with adverse outcomes. Placental lipid droplets (LD) have been implicated in maternal-fetal lipid transfer but it is not known whether placental LD fat composition is modifiable. We evaluated the effects of a diet and physical activity intervention in obese pregnant women compared to routine antenatal care (UPBEAT study) on placental LD composition. LD were isolated by ultracentrifugation. Total FAs and phospholipids (phosphatidylcholines, PCs; sphingomyelins, SMs and lyso-phosphatidylcholines, Lyso-PCs) were analyzed by LC-MS/MS. Placenta MFSD2a expression was assessed by western blot. Placental LDs from obese women were comprised of predominantly saturated and monounsaturated FAs. TG and Chol composition was similar between intervention (n = 20) and control (n = 23) groups. PCs containing dihomo-ɣ-linolenic acid in LD were positively associated with gestational weight gain (P < 0.007), and lowered by the intervention. In the whole sample, PCs carrying DHA and arachidonic acid were inversely associated with placental weight. Placenta MFSD2a expression was associated with DHA cord blood metabolites and relationships were observed between LD lipids, especially DHA carrying species, and cord blood metabolites. We describe placenta LD composition for the first time and demonstrate modest, potentially beneficial effects of a lifestyle intervention on LD FAs in obese pregnant women.

Keywords: Lipid droplets; MFSD2a; Omega-3 fatty acids; Phospholipids; Placenta; Randomized controlled trial.