Antisenescence effect of mouse embryonic stem cell conditioned medium through a PDGF/FGF pathway. 
Cellular senescence, an irreversible state of growth arrest, underlies organismal aging and age-related diseases.  Recent evidence suggests that aging intervention based on inhibition of cellular senescence might be a promising strategy for treatment of aging and age-related diseases.  Embryonic stem cells (ESCs) and ESC conditioned medium (CM) have been suggested as a desirable source for regenerative medicine.  However, effects of ESC-CM on cellular senescence remain to be determined.  We found that treatment of senescent human dermal fibroblasts with CM from mouse ESCs (mESCs) decreases senescence phenotypes.  We found that platelet-derived growth factor BB in mESC-CM plays a critical role in antisenescence effect of mESC-CM through up-regulation of fibroblast growth factor 2.  We confirmed that mESC-CM treatment accelerates the wound-healing process by down-regulating senescence-associated p53 expression in in vivo models.  Taken together, our results suggest that mESC-CM has the ability to suppress cellular senescence and maintain proliferative capacity.  Therefore, this strategy might emerge as a novel therapeutic strategy for aging and age-related diseases.