Chemical Inhibition of Mitochondrial Fission Improves Mitochondrial Function and Subdues Hyperglycemia Induced Stress in Placental Trophoblast Cells

Gestational diabetes mellitus (GDM) is a metabolic complication that affects millions of pregnant women in the world. Placental tissue function is endangered by hyperglycemia during GDM, which is correlated to increased incidences of pregnancy complications. Recently we showed that due to a significant decrease in mitochondrial fusion, mitochondrial dynamics equilibrium is altered in placental tissues from GDM patients. It is not known whether the decrease in mitochondrial fusion causes a decrease in mitochondrial function in placental cells. Here we show that chemical inhibition of mitochondrial fission in cultured placental trophoblast cells leads to an increase in mitochondrial fusion and improves the physiological state of these cells and hence, their capacity to cope in a hyperglycemic environment. Specifically, mitochondrial fission inhibition led to a reduction in reactive oxygen species (ROS) generation, mitochondrial unfolded protein marker expressions, and mitochondrial depolarization. It supported the increase in mitochondrial antioxidant enzyme expressions as well. Mitochondrial fission inhibition also increases the placental cell insulin sensitivity during hyperglycemia. Our results suggest that mitochondrial fusion/fission equilibrium is critical for placental cell function and signify the therapeutic potential of small molecule inhibitors of fission during GDM.