A molecule called Notum from a type of gut-lining cell inhibits gut cell regeneration and increases with age
In a rapidly ageing population, understanding how our cells change as we get older has never been more important. In the intestinal epithelium, the lining of our gut, stem cells divide to renew surrounding tissues, but this regeneration slows as we age. Using the ability of cultured intestinal stem cells (ISCs) to form clusters of cells, known as organoids (pictured), as a measure of their regenerative capacity, a recent study revealed that signals from neighbouring Paneth cells (in red) are responsible for this decline. Young ISCs surrounded by old Paneth cells show reduced organoid formation, as older Paneth cells secrete higher levels of Notum, an inhibitor of the critical Wnt signalling pathway required for stem cell activity. By contrast, blocking Notum boosts activity in old ISCs, suggesting that this could be a promising way to stimulate regeneration and thus help intestinal tissues to recover from damage, especially in older patients.
Written by Emmanuelle Briolat
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.