Osteoblastogenesis stimulation by human umbilical cord stem cell secretome during maxillary expansion

Maxillary expansion induced by mechanical force (MEMF) is a standard orthodontic approach for correcting transverse maxillary deficiency. The human umbilical cord mesenchymal stem cell secretome (HUCMSC-S) has the potential to stimulate accelerate bone remodeling. This study aimed to evaluate local HUCMSC-S application effect during MEMF on the expression bone morphogenetic protein (BMP)-2, BMP-4, BMP-7, vascular endothelial growth factor (VEGF), insulin-like growth factor-1 (IGF-1), transforming growth factor-beta (TGF-β), and fibroblast growth factor-2 (FGF-2) in a Wistar rat (Rattus norvegicus).

Twenty-four healthy male Wistar rats (R. norvegicus) were randomly divided into four groups: K1: blank, without treatment; K2: rats with an activated MEMF and PBS; P1: rats with an activated MEMF and HUCMSC-S; and P2: rats with an inactivated MEMF and HUCMSC-S. MEMF experimental animals was performed by applying a force of 0.42 N using a loop and observed for 28 days. The HUCMSC-S single dose was 2 x 10⁶ cells (equivalent to 5 x 10⁵ cells in 50 μl of aMEM) every two days application. After 28 days, the maxillary containing the midpalatal suture were harvested. Immunohistochemical analysis was performed to quantify the positive expression of BMP-2, BMP-4, BMP-7, VEGF, TGF-β, IGF-1 and FGF-2.

HUCMSC-S local application during active expansion (Group P1) significantly upregulated the expression of BMP-2, BMP-4, BMP-7, VEGF, TGF-β, IGF-1, and FGF-2 in the midpalatal suture on day 28 compared to the control groups (P ≤ 0.05).

HUCMSC-S local application effectively stimulates osteoblastogenesis and angiogenesis markers in the midpalatal suture during MEMF.