Age-related changes in lung function in National Center for Geriatrics and Gerontology Aging Farm C57Bl/6N mice.

Aging is an extremely complex biological process, and various models, from unicellular organisms to mammals, have been used in its research. The mouse is the most widely used model for studying human aging and diseases due to its high homology and well-established strategies for genetic manipulation. In spite of these advantages, the maximum lifespan of laboratory mice is nearly three years, which makes it time-consuming to obtain animals of the desired age. To avoid these issues and efficiently conduct aging research, the National Center for Geriatrics and Gerontology operates the "Aging Farm", a system that supplies aging animals in response to researchers' requests. In the present study, as part of the Aging Farm project, we examined changes in the physiological functions of and gene expression in the lung tissues of aging-grown animals as they aged. A decline in the physiological function of the lungs was already apparent before 6 months of age and continued until at least 1 year of age. On the other hand, gene expression profiling by RNA sequencing showed small changes in the early stages of aging, but more pronounced changes at 12 and 24 months of age than at 3 months of age. Age-related lung tissue changes are considered to be involved in the pathogenesis of various chronic respiratory diseases, and the characterization of aging animals will ensure the quality of the Aging Farm as a resource for aging research.