Fig. 5.

Basal activation of SHH pathway is partially responsible for the angiogenic properties of WJ-MSC. 5E1 was used in the absence of serum to evaluate the contribution of autocrine/paracrine-secreted SHH. After 48 h of treatment, gene expression was evaluated using GAPDH as a normalizing gene and 0% fetal bovine serum (FBS) as control. Inhibition of the SHH pathway induced a significant decrease in the levels of (a) PTCH1, (b) GLI1, and (c) ANGPT1 in three independent WJ-MSC samples. From the same cell cultures, conditioned medium (CM) was generated after 48 h in presence of 5E1 and the angiogenic potential was challenged in a tubule formation assay. HUVEC were stimulated with control CM (d) or CM from WJ-MSC treated with 5E1 (CM + 5E1) (e). Quantification of (f) branching points and (g) tubules showed that the presence of 5E1 in WJ-MSC cultures induced a decrease in the angiogenic potential. h–m To decode this effect we analyzed the effect of 5E1 on the secretion of angiogenic factors via proteome analysis. We only observed a significant diminished angiogenic factor secretion for (k) granulocyte-macrophage colony-stimulating factor (GM-CSF), (l) matrix metallopeptidase-9 (MMP-9), and (m) urokinase-type plasminogen activator (uPA). *P < 0.05, unpaired Student’s t test. ANGPT1 angiopoietin 1, ns not significant