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Biology subjects

Frank, D. B.

Publications and source records attributed to Frank, D. B..

2 recordsLinked to original sources

Circadian regulation of lung repair and regeneration

Optimal lung repair and regeneration is essential for recovery from viral infections such as that induced by influenza A virus (IAV). We have previously demonstrated that lung inflammation induced by IAV is under circadian control. However, it is not known if the circadian clock exerts its influence on lung repair and regenerative processes independent of acute inflammation from IAV. Here, we demonstrate for the first time that lung organoids have a functional clock as they mature and that the absence of an intact circadian clock impairs regenerative capacity. Using several models of circadian disruption, we show that with the absence of an intact clock lung proliferation is disrupted. Further, we find that the circadian clock acts through direct control of the Wnt/{beta}-catenin pathway. We speculate, that adding the circadian dimension to the critical process of lung repair and regeneration will lead to novel therapies and improve outcomes. Finally, we use data from UK Biobank to demonstrate at the population level, the role of poor circadian rhythms in mediating negative outcomes following lung infection.

cell biology↗

GSK3 inhibition rescues growth and telomere dysfunction in dyskeratosis congenita iPSC-derived type II alveolar epithelial cells

Dyskeratosis congenita (DC) is a rare genetic disorder characterized by deficiencies in telomere maintenance leading to very short telomeres and the premature onset of certain age-related diseases, including pulmonary fibrosis (PF). PF is thought to derive from epithelial failure, particularly that of type II alveolar epithelial (AT2) cells, which are highly dependent on Wnt signaling during development and adult regeneration. We use human iPSC-derived AT2 (iAT2) cells to model how short telomeres affect AT2 cells. Cultured DC mutant iAT2 cells accumulate shortened, uncapped telomeres and manifest defects in the growth of alveolospheres, hallmarks of senescence, and apparent defects in Wnt signaling. The GSK3 inhibitor, CHIR99021, which mimics the output of canonical Wnt signaling, enhances telomerase activity and rescues the defects. These findings support further investigation of Wnt agonists as potential therapies for DC related pathologies.

cell biology↗