Human induced pluripotent stem cells provide an unlimited, scalable source of youthful tissue progenitors and secretome for regenerative therapies. The aim of our study was to assess the potential of conditioned medium (CM) derived from hiPSC-mesenchymal progenitors (hiPSC-MPs) to stimulate osteogenic differentiation of adult and aged human bone marrow-mesenchymal stromal cells (MSCs). In addition, we evaluated whether extended cultivation or osteogenic pre-differentiation of hiPSC-MPs could enhance the CM stimulatory activity.