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Tipple, T. E.

Publications and source records attributed to Tipple, T. E..

2 recordsLinked to original sources

3-Mercaptopyruvate Sulfurtransferase (MPST) Regulates Mitochondrial Metabolism and Epithelial Differentiation in Neonatal Patient-derived Airway Cells

Early-life airway epithelial development relies on tightly coordinated mitochondrial metabolic programs, yet the pathways that govern normal epithelial maturation during this vulnerable developmental window remain poorly defined. Hyperoxia disrupts airway epithelial maturation, contributing to lung injury and airway remodeling in infants with bronchopulmonary dysplasia (BPD), underscoring the need to identify mitochondrial pathways that regulate early epithelial differentiation. 3-Mercaptopyruvate sulfurtransferase (MPST), a mitochondrial sulfur metabolism enzyme, supports mitochondrial metabolic and bioenergetic function, but its role in human airway epithelial development is unknown. In this study, we used neonatal patient-derived tracheal airway epithelial cells (nTAECs) in a three-dimensional air-liquid interface (ALI) model to show that hyperoxia reduces MPST protein abundance. To determine how MPST loss alters early epithelial differentiation and metabolic homeostasis we used RNAi to knock down MPST during ALI differentiation. MPST loss in nTAECs induced early (ALI day 3) transcriptomic shifts involving mitochondrial metabolic pathways, epithelial differentiation programs, and stress-response signature corresponding with decreased ciliated cell numbers during mid-differentiation phase (ALI day 7). Metabolic flux analysis revealed significantly reduced mitochondrial respiration without compensatory increase in glycolysis, indicative of disrupted metabolic flexibility. Together, these data show that MPST is essential for maintaining mitochondrial metabolic integrity necessary for normal airway epithelial development. Loss of MPST creates a developmental vulnerability that may contribute to hyperoxia-induced airway injury in neonates. Targeting MPST-dependent pathways could represent a new strategy to preserve airway health in infants at risk for BPD airway remodeling. NEW & NOTEWORTHYThis study identifies MPST as a previously unrecognized regulator of neonatal airway epithelial development. In our neonatal patient-derived three-dimensional organotypic model, hyperoxia reduces MPST, and MPST loss alters mitochondrial metabolism and epithelial differentiation programs. These findings indicate that MPST deficiency contributes to mitochondrial dysfunction under hyperoxic conditions and highlight MPST-linked pathways as potential therapeutic targets to mitigate early-life airway injury and remodeling relevant to infants with bronchopulmonary dysplasia.

developmental biology↗

Quantitative Proteomics Links Mitochondrial Dysfunction to Metabolic Changes and Epithelial Differentiation Defects in Hyperoxia-Exposed Neonatal Airway Cells

Premature infants often require supplemental oxygen therapy, however, exposure to supraphysiological oxygen (hyperoxia) can disrupt normal lung development and contribute to bronchopulmonary dysplasia (BPD). Mitochondrial dysfunction is increasingly recognized as a contributor to hyperoxia-induced BPD. However, the effects of hyperoxia on mitochondrial function and mucociliary differentiation in the developing upper airway epithelium remain poorly understood. This study tested the hypothesis that hyperoxia impairs neonatal airway mucociliary differentiation by disrupting mitochondrial bioenergetic function. Neonatal tracheal airway epithelial cells (nTAECs) from term infants (n=5) were cultured in a 3D air-liquid interface (ALI) model and exposed to 60% O2 during the mid-phase of differentiation (ALI day 7-14). Cellular phenotype was assessed using immunofluorescence staining and gene expression analyses. Mitochondrial function was evaluated through Seahorse metabolic flux analysis, and global protein changes were characterized by quantitative proteomics. Hyperoxia exposure significantly impaired terminal epithelial differentiation, characterized by reductions in ciliated and goblet cells. Seahorse assay revealed a decrease in baseline oxygen consumption and mitochondrial ATP production, accompanied by a compensatory increase in glycolytic ATP production. Quantitative proteomics identified disruption of mitochondrial Complex I as a central feature of the hyperoxic response. Downstream proteomic pathway analyses further confirmed the metabolic shift from mitochondrial to glycolytic ATP production and demonstrated altered epithelial differentiation pathways, including NOTCH and TGF-{beta} signaling. These findings reveal that moderate hyperoxia impairs mitochondrial bioenergetics and alters metabolic programming, leading to disrupted mucociliary differentiation. Future in vivo studies should evaluate mitochondrial oxidative fitness as a therapeutic target in neonatal lung disease. NEW & NOTEWORTHYWe report that moderate hyperoxia during a critical window of mucociliary differentiation disrupts terminal maturation in neonatal airway epithelial cells cultured in a 3D model. Hyperoxia induced mitochondrial bioenergetic dysfunction and metabolic reprogramming, with proteomic analysis identifying Complex I disruption as a key driver of impaired differentiation. Overall, these findings reveal a previously underrecognized link between mitochondrial bioenergetics and airway epithelial development, positioning metabolic dysfunction as an early trigger of hyperoxia-induced neonatal airway injury.

developmental biology↗