Semaglutide Induces Oxidative Stress and Differentially Modulates mTOR-Dependent Growth and Invasion in Human Trophoblast Cell Models: Implications for Placental Function

Semaglutide, a long-acting glucagon-like peptide-1 receptor agonist (GLP-1RA), has transformed obesity and diabetes management. However, its expanding use among reproductive-age women raises concerns about potential effects on early placental development. We examined semaglutide’s impact on two human trophoblast cell lines: Swan71 (invasive extravillous) and BeWO (syncytiotrophoblast-like). Cells were treated with semaglutide (100 nM) for 24 h, and proliferation, viability, mitochondrial respiration, oxidative stress, signaling pathways, and invasiveness were evaluated. Semaglutide significantly reduced proliferation in Swan71 cells and increased it in BeWO cells, with no significant change in viability for Swan71 and a slight increase for BeWO. Western blot analysis revealed altered phosphorylation of key signaling proteins, including mTOR, p70S6K, 4EBP1, AKT, and ERK, as well as increased AMPK phosphorylation, indicating a shift toward catabolic signaling. Reactive oxygen species (ROS) accumulation increased markedly, accompanied by altered oxygen consumption rates—reduced in Swan71 cells and elevated in BeWO cells. Functionally, semaglutide suppressed Swan71 invasion through Matrigel by approximately three-fold. These findings suggest that semaglutide induces oxidative and metabolic stress in trophoblasts and is associated with altered mTOR-mediated signaling and reduced invasive potential. Such cellular alterations may contribute to compromised placental development and uterine vascular remodeling if exposure occurs near conception. While clinical data remain limited, this study provides mechanistic insight supporting caution in the use of semaglutide during the periconception period and underscores the need for targeted reproductive safety studies.