Allium fistulosum (Welsh onion) and Portulaca oleracea increase longitudinal bone growth in weanling rats possibly by promoting TGF-β and IGF-1 signaling

Longitudinal bone growth mainly occurs during adolescence and can be enhanced by growth hormones. We hypothesized that water extracts from roots of Allium fistulosum L. (Welsh onion, WO; 15 or 45 mg/kg bw/day) and Portulaca oleracea L. (PO; 15 or 45 mg/kg bw/day) can stimulate longitudinal bone growth in weanling male rats for 4 weeks. Femur and tibia lengths were higher in the WO-H and PO-H groups than in the control. The proliferative and hypertrophic zones of the growth plate were greater in the legs of WO-H and PO-H rats than in the control; a similar increase was observed in the positive-control (growth hormone, 20 mu g/kg bw/day). WO-H and PO-H treatments were found to potentiate insulin-like growth factor-1 (IGF-1) signaling (pIRS-2 -> pAkt) in MG-63 osteoblasts compared to control. WO-H and PO increased cell proliferation possibly by activating transforming growth factor (TGF)-beta signaling via elevated BMP-2 and Smad4 expression in MG-63 cells. In conclusion, WO and PO are potential to promote the proliferation of the leg growth plate similar to growth hormone.