Date of Award
Doctor of Philosophy in Nursing (PhD)
Sandra K. Hanneman, Ph.D
Madelene Ottosen, Ph.D
Binoy Shivanna, M.D.
Sundeep Keswani, M.D.
Background: Congenital diaphragmatic hernia (CDH) is one of the most complex congenital disorders, characterized by pulmonary hypertension and hypoplasia. CDH-associated pulmonary hypertension (CDH-PH) features devastating morbidity and mortality (25-30%) among neonates. An unmet need is determining the mechanisms triggering CDH-PH to save infants and improve their quality of life. Prior data suggest abnormal remodeling of the pulmonary vascular extracellular matrix, presumed to be driven by endothelial-to-mesenchymal transition (EndoMT), hinders postnatal vasodilation and limits efficacy of anti-PH therapy in CDH. Although abnormal vascular development and remodeling are known CDH traits, there is limited data on the role of EndoMT in CDH-PH.
Objective: The purpose of the study is to investigate how EndoMT contributes to CDH-PH by identifying cells undergoing EndoMT as noted by alpha smooth muscle actin (α-SMA) expression in human umbilical vein endothelial cells (HUVECs), and lung tissue obtained from murine pups using the nitrofen model.
Methods: N=8 CDH and N=8 control HUVECs were stained for α-SMA and CD31 after being exposed for 24hrs to TGFB, a known EndoMT promoter. N=8 nitrofen and N=8 control murine pup lungs were also stained for α-SMA and CD31. α-SMA and CD31 expression was quantified in the HUVECs and murine tissue using Fiji imaging software and normalized to the total number of cells per slide noted by DAPI staining.
Results: CDH HUVECs demonstrated a 1.1-fold increase in α-SMA expression (p= 0.02). The murine model did not show statistical significance between nitrofen and control pup lungs; however, there was a 0.4-fold increase in α-SMA expression with a 0.8-fold decrease in CD31 expression in the nitrofen pup lungs when compared to controls.
Conclusion: These results suggest EndoMT could potentially play a role in the ECM remodeling seen in CDH-PH.
Gilley, Jamie L., "Endothelial to Mesenchymal Transition in Human and Murine Congenital Diaphragmatic Hernia Pulmonary Hypertension" (2023). Dissertations (Open Access). 64.
congenital diaphragmatic hernia, endothelial to mesenchymal transition, alpha smooth muscle actin