Function of TGF-beta and p38 MAKP signaling pathway in osteoblast differentiation from rat adipose-derived stem cells.

BACKGROUND Adipose-derived stem cells (ADSCs) are multipotent progenitors that can commit to osteoblast, chondrocyte, adipocyte and several other lineages. The proper utilization of stem cells for clinical application requires an integrated understanding of multiple signal inputs that control maintenance of stemness, proliferation and differentiation. MATERIALS AND METHODS In this study, ADSCs in rat were isolated from subcutaneous tissues of abdomen and inguinal fat pads, purified and expanded in vitro. Bone morphogenetic protein 2, TGF-beta 1, SB203580 (P38 MAPK inhibitor), Noggin (BMP inhibitor) and SB431542 (TGF-beta inhibitor) were used for differentiation into osteoblasts. RESULTS Both TGF-beta signaling pathway and p38 MAKP signaling pathway could affect the differential direction of the ADSCs. PCR assays indicated that both TGF-beta signaling pathway and p38 MAKP signaling pathway played a crucial roles in osteoblasts differentiation of the ADSCs, the members included Smad 1, Smad 5, Smad 8, P38, ASK1, MKK3, MKK6, Runx 2, collagen type 1, and osteopontin. CONCLUSIONS This research provides a theoretical basis and experimental evidence for therapeutic application of rat ADSCs to treat bone injury.