Low concentrations of caffeic acid phenethyl ester stimulate osteogenesis in vitro

[Display omitted] •CAPE can modulate ALP activity.•CAPE promotes the gene expression of osteoblastic markers.•Low concentrations of CAPE stimulate osteogenesis in vitro. The aim of this study was to evaluate the effects of caffeic acid phenethyl ester (CAPE) on osteoblast-like cell cultures (SAOS-2). SAOS-2 were exposed to CAPE at 1 nM, 10 nM, 100 nM, 1 μM, and 10 μM. Non-exposed cultures were used as control. The following parameters were assayed: 1) cell viability at 1, 3, and 7 days; 2) alkaline phosphatase (ALP) activity at 5 and 10 days; 3) matrix mineralization at 14 days; and 4) Runt-related transcription factor 2 (RUNX2), ALP, osteopontin (SPP1), and osteocalcin (BGLAP) gene expression at 5 and 10 days. The data were analyzed by ANOVA two-way or Kruskal-Wallis (α = 5%). At day 1, cell viability was similar among all groups (p > 0.05). At days 3 and 7, cultures exposed to CAPE at 10 μM exhibited a significant reduction in cell viability compared with the others groups (p < 0.05). At day 5, ALP activity was similar among all experimental groups; at day 10, however, the stain intensity was higher in cultures exposed to CAPE at 100 nM and 10 nM in comparison with the other groups (p < 0.05). At days 5 and 10, RUNX2, ALP, SPP1, and BGLAP gene expression was greater in cultures exposed to CAPE in comparison with the control (p < 0.05). At day 14, matrix mineralization was similar in cultures exposed to CAPE at 1 nM and 10 nM (p > 0.05), but superior to those ones observed in the other experimental groups (p < 0.05). CAPE at low concentrations can positively module the osteogenesis in vitro.