Bone mineral density (BMD) changes in the animals. Percent changes of BMD relative to baseline of each group (A) and BMD relative to the ovariectomy (OVX)-Vehicle group (B). Ten-week-old female nude mice were sham-operated (Sham-op) or OVX and randomized into six groups; Sham-op+Vehicle mice (n=8), OVX+Zoledronate (Zol) mice (n=8), OVX+human umbilical cord blood mesenchymal stem cell (hUCB-MSC)-conditioned medium (OVX+CM) mice (n=8), OVX+hUCB-MSCs (n=8), OVX+human dermal fibroblast (hDFB) (OVX+DFB), or OVX+Vehicle mice (n=8). The mice were injected with vehicle, hUCB-MSC CM, hUCB-MSCs, or hDFBs at days 1, 2, 8, and 9, and BMD (g/cm2) was measured with a PIXImus densitometer at 4-week intervals as indicated. For the OVX-Zol group, zoledronate (100 μg/kg) was given at days 1 and 8. Data are the means±standard deviation (SD). *p<0.01 versus OVX-Vehicle at 4 weeks, #p<0.01 versus OVX-Vehicle at 8 weeks.