PGK1 Regulates Oxidative Stress in Gestational Diabetes Mellitus through the Estradiol-Keap1-Nrf2 Pathway

Gestational diabetes mellitus (GDM), the most common pregnancy-related metabolic disorder, is characterized by exacerbated oxidative stress (OS). The inhibition of phosphoglycerate kinase 1 (PGK1), the first ATP-generating enzyme in the glycolytic pathway, activates Keap1-Nrf2 antioxidant pathways and reduces OS. However, the detailed roles of PGK1 in GDM remain unexplored. Disruption of pro-oxidant/antioxidant homeostasis was observed in the placentas of GDM patients. PGK1 was significantly upregulated in both human GDM placentas and streptozotocin (STZ)-induced model mice. Pharmacological inhibition of PGK1 in vivo ameliorated placental dysfunction, attenuated excessive ROS production, and improved pregnancy outcomes. Lentivirus-mediated PGK1 knockdown in HTR8/SVneo trophoblasts increased Nrf2-dependent antioxidant protein expression while reducing ROS generation. Mechanistically, PGK1 inhibition elevated estradiol levels, facilitating Keap1 dimerization, and this dimerization destabilized the Keap1-Nrf2 complex, enabling Nrf2 accumulation and antioxidant activation. Exogenous estradiol supplementation recapitulated the effect of inhibiting PGK1 by enhancing Keap1 dimer formation, effectively mitigating placental OS and adverse pregnancy phenotypes in GDM models. This study elucidates the critical role of PGK1 in restoring redox homeostasis through the estradiol-Keap1-Nrf2 axis in the pathogenesis of GDM. PGK1/estradiol crosstalk represents a druggable target, and pharmacological PGK1 inhibition has translational potential for mitigating oxidative stress-related pregnancy complications.