Five lipids revealed a divide between active and inactive pregnancies

by · News-Medical

A closer look at the placental lipidome reveals molecular differences between active and inactive pregnancies, offering new clues about how maternal movement may shape the environment supporting fetal development.

Routine exercise during pregnancy may confer sustained health benefits, as women who stay active during pregnancy have a lower risk of several pregnancy-related complications. Physical activity (PA) has also been linked to a lower risk of some adverse health outcomes in the offspring; however, the biological mechanisms behind these associations remain unclear.

Tracking activity and placental lipids

In this study, researchers examined lipid changes in the placenta of physically active and inactive individuals. Researchers recruited participants across Ottawa and Baton Rouge from the PLACENTA and Expecting Success trials.

The Canadian Institutes for Health Research (CIHR) funded the former, while the latter received funding from the National Institutes of Health (NIH). In both projects, participants were aged 18 to 40 years and had singleton pregnancies. Participants with pre-existing diabetes, untreated thyroid disease, or medicated hypertension were excluded.

A total of 36 placental samples collected at term from women with uncomplicated pregnancies underwent lipidomic analyses using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The team also performed Western blot assays to analyze the expression of the major facilitator superfamily domain-containing 2a (MFSD2a) protein, which is associated with DHA transfer and uptake at the placenta and the blood-brain barrier (BBB).

In the trial, participants were randomized to no intervention, in-person intervention, or a remote intervention; the intervention arms received dietary and exercise advice along with behavior-modification counseling. Dietary intake was assessed using the automated self-administered dietary assessment (ASA24) tool and participant diet recalls.

Participants were classified as active if third-trimester accelerometer data indicated that they met the recommended 150 minutes of moderate PA per week. Principal component analysis (PCA) showed modest separation in overall lipid profiles between the groups, while supervised partial least squares discriminant analysis (PLS-DA) further distinguished active from inactive participants.

Physical activity leaves a distinct placental lipid signature.

The sample population comprised 17 inactive and 19 active individuals. The only significant difference between the active and inactive groups was third-trimester moderate-to-vigorous PA (34.8 vs. 10.8 minutes per day). In total, the team annotated 192 lipids, 39 of which differed significantly after adjustment for multiple comparisons. After applying an additional fold-change threshold, 34 lipids met both criteria.

Five lipid species, TG 16:0/18:0/18:1, TG 18:0/18:1/18:1, PE 18:1/22:5, cholesteryl palmitate, and PC 16:0/16:2, perfectly distinguished the active and inactive groups within this study sample. Their potential use as PA biomarkers will require validation in larger, independent populations. The phosphatidylserine decarboxylase (PISD) pathway was also enriched in the active group.

What placental lipids could reveal about activity in pregnancy?

The findings indicate differences in placental lipid profiles between physically inactive and active women during pregnancy, suggesting that PA may influence lipid-related functions such as fetal nutrient transport and energy metabolism. If confirmed in larger studies, some of the identified lipids could serve as PA biomarkers.

In the future, researchers could include cord blood lipid analysis and explore associations of maternal adiposity and PA (including muscle-strengthening exercises) with fetal growth outcomes. These studies could clarify the biological significance of these lipid differences and how they relate to pregnancy and fetal outcomes.

Journal reference: