Identifying and highlighting the impactful VTPP publications of each month. The goal is to capture these articles for annual VTPP research highlights. I hope the articles serve as an accessible archive and reference of our very best VTPP Science.

The May 2021 highlighted “VTPP Science in Action” article (link included below) comes from the laboratory of Dr. Regina Brunauer. The article (the result of a collaborative effort between the Brunauer, Dawson and Muneoka labs) provides strong evidence that bone regeneration is compromised by age (what isn’t?), but surprisingly not by limiting bone cell progenitors (as might have been thought) but by altering the bone formation activity of bone forming osteoblasts. Using the mouse digit as a mammalian regenerative system, Dr. Brunauer and colleagues demonstrate an important age-related delay in the regenerative response. However, although delayed, the regenerative response does ensue and reaches completion. These data demonstrate that the aged adult mouse digit is indeed capable of completing a regeneration program.  Further, this work suggests that in the aged mammal, regeneration is not limited by progenitor cell availability, but by the disruption of the temporal regulation and reduced osteoblast activity. Subsequently, many strategies that seek to deploy stem cell therapy in the context of regenerative medicine may need to be repositioned and the concept of timing of treatment expanded considerably. The figure below (Figure 1 from the paper) shows microCT renderings and quantitation of the regeneration of the digit in young (2-3 month) vs. aged (12-13 month old) mice. The delay in regeneration is clearly visible in the images and is quantified on b-d below. Days post amputation (DPA) shows the age-related delay in bone length (BL), bone volume (BV) and rates of formation and degradation (BV/day). Congratulations to all involved in these important and informative studies. The article can be found at: DOI: 10.1093/gerona/glab131