Diabetic wounds are a growing problem worldwide. One solution could lie in a hormone secreted by the parathyroid. PTH is critical for re-growing bone. But evidence suggests that it could also help regenerate skin and blood vessels. Researchers recently tested this hypothesis on rats. Applying a synthetic version of PTH to diabetic wounds significantly improved wound healing. But not as they believed it would. Synthetic PTH did not appear to directly activate the cells it repaired. Instead, separate experiments showed that the PTH derivative indirectly led to repair, using exosomes, tiny sacs ejected by cells to communicate with other cells. If replicated in more realistic models of diabetes, these findings could lead to a powerful new way to accelerate wound healing.