Changes in mitochondrial respiration in the human placenta over gestation

Area of Science:

• Mitochondrial physiology
• Placental biology
• Perinatal adaptations

Background:

• Placental mitochondria face dynamic oxygen levels throughout gestation.
• Adaptation of placental mitochondrial respiration to oxygen variations is unknown.
• The impact of in vitro culture on placental mitochondria requires investigation.

Purpose of the Study:

• To investigate placental mitochondrial respiration adaptation to gestational oxygen changes.
• To determine the effects of in vitro culture on placental mitochondrial function.

Main Methods:

• Mitochondrial respirometry on placental tissue from first trimester and term pregnancies.
• Assessment of respiration states and substrate utilization.
• Culture of placental explants for up to 96 hours with subsequent respiration measurement.

Main Results:

• Mitochondrial respiration decreased at 11 weeks gestation; content increased at 12-13 weeks.
• Term placentae exhibited higher oxidative phosphorylation, respiratory capacity, and mitochondrial content than first trimester.
• Labored placentae showed increased respiration; in vitro culture depressed respiration and altered apoptosis/autophagy markers.

Conclusions:

• Placental mitochondrial respiration and content change significantly with gestation and labor.
• Labor may induce adaptations to ischemia-reperfusion, while term mitochondria are more susceptible to in vitro culture effects.
• The metabolic plasticity of placental mitochondria is crucial for understanding placenta-mediated diseases.