Oral or Poster Presentation
Concurrent Session 1B - Placental Fetal Physiology
Introduction: Placental mitochondria are the primary source of ATP for fetal growth and development. Exercise during pregnancy provides health benefits for both the mother and fetus; however, little is known about the effect of maternal exercise on placental mitochondria. It is hypothesized that mitochondrial expression and function will be increased in term placenta of active mothers.
Methods: Pregnant women were recruited for an observational study where their physical activity levels during second trimester were assessed using an accelerometer. Women engaging in 30min/day of MVPA were categorized as active (n=5) while women engaging in 3 min/day MVPA were deemed inactive (n=5). At birth, placental tissue samples from central (near cord insertion) and peripheral regions were analyzed to assess mitochondrial subunit expression by western blot and mitochondria function were measured by citrate synthase assay. Mitochondrial oxidative stress were measured by SOD1/2 protein levels. Two-way ANOVA were used to compare mitochondrial expression and function between tissue location and physical activity groups.
Results: No significant differences were found in mitochondrial protein expression, SOD1 expression, and citrate synthase activity between active and inactive groups. In peripheral tissue of active particpants, expression of CI (mean difference, MD:1.025 ; 95% confidence interval, CI: 0.5843to1.466), CII (MD:1.217;CI:0.4771to1.957), and CIV (MD:0.2624;CI:0.006889 to0.5178) were increased compared to central (p<0.05). In inactive participants, expression of CII (MD:0.6253;CI:0.09667to1.154), CIII (MD:1.926;CI:0.3987to3.453), and CV (MD:1.110;CI:0.1440to2.075) (p<0.05) were increased in peripheral tissue compared to central. When populations were combined, all but subunit CIV saw an increased protein expression in peripheral tissue (p<0.001).
Conclusion: Physical activity during pregnancy does not appear to impact overall placental mitochondria expression, however, its function is still debatable. The differences found between active and inactive women in complex expression of peripheral placenta samples eludes to the possibility of altered function with exercise; this warrants further investigation.