Single-cell RNA sequencing profiling of the effects of aging on alveolar stem cells.

The aging of alveolar stem cells has been linked to many chronic lung diseases, including pulmonary fibrosis. However, the effects of aging on alveolar stem cells during homeostasis and post-injury alveolar repair have not been well characterized. Here we conducted a single-cell RNA sequencing (scRNA-seq) analysis of alveolar stem cells of 3-month-old and 12-month-old mice to characterize the aging effect on alveolar stem cells. Our results have shown that the transcriptomes of alveolar stem cells of 3-month-old and 12-month-old mice are not significantly different under the steady condition. However, after a bleomycin-induced lung injury, the alveolar stem cells of 12-month-old mice show enhanced inflammatory responses and decreased lipid metabolism. Our study suggests a close relationship among aging, lipid metabolism, inflammatory responses and chronic lung diseases.