The heart and placenta have simultaneous embryologic development, the interactions between the two organs representing the heart–placental axis. They both share key developmental pathways, one of which involves the placental growth factor (PlGF) and its receptor, vascular endothelial growth factor receptor-1 (VEGFR-1). The aim of this study was to evaluate the placental pathology and the expression patterns of PlGF and VEGFR-1 in pregnancies with fetuses with congenital heart defects (CHDs). We analyzed placental gross and microscopic alterations between placentas from pregnancies with CHD fetuses and pregnancies with structurally normal heart fetuses. We also performed the immunohistochemical (IHC) assessment of the placental expression of PlGF and VEGFR-1 in the two groups. We discovered significant gross placental abnormalities in pregnancies with CHD fetuses, including a shorter umbilical cord, marginal or velamentous umbilical cord insertion, and a lower fetal-to-placental weight ratio. Also, 88.2% of the placentas in the CHD group displayed microscopic pathologic aspects. We demonstrated significant placental immunostaining for PlGF and VEGFR-1 in the syncytiotrophoblast and decidual cells compared to villous endothelial cells. We identified a lower placental IHC expression of PlGF in pregnancies with CHD fetuses compared to controls but no differences in the placental immunostaining pattern for VEGFR-1 between the two groups. Our study uncovered a potential role played by the PlGF/VEGFR-1 pathway in the development of CHDs through placental-mediated mechanisms.

Podocyte injury is a hallmark of both focal segmental glomerulosclerosis (FSGS) and minimal change disease (MCD), ultimately reflected in foot process effacement and proteinuria. Triggers and pathogenic pathways leading to podocyte cytoskeleton rearrangements are, however, incompletely explained. Here, we aimed to contribute to the understanding of these pathways using tissue bottom-up proteomic profiling of laser-capture microdissected glomeruli from MCD and FSGS. Forty-six differentially expressed proteins were identified between the two groups (p < 0.05, |FC| ≥ 1.2). Pathway analysis showed that 16 out of 46 proteins were associated with the immune system, with E2 ubiquitin-conjugating enzyme (UBE2K) and complement factor H-related protein-1 (CFHR1) yielding the highest fold change in FSGS compared to MCD. The two target proteins were further validated through immunohistochemistry, confirming the podocyte localization of UBE2K and endothelial staining of CFHR. Additionally, several other differentially expressed proteins were linked to the cytoskeleton structure and its regulation. Our results point to the possibility that complement dysregulation may be the source of cytoskeleton rearrangement in FSGS.