Possible involvement of pro-angiogenic activities in the traditional use of the stembark of Oenocarpus bacaba Mart. (Arecaceae) for wound healing in the Republic of Suriname (South America)

Angiogenesis is an important part of the wound healing process. In this study, the aqueous extracts from seven plant species that are used for wound care in the Republic of Suriname (South America), were evaluated at sub-toxic concentrations for their stimulatory effects on the closure of scratch-wounds in cultured human umbilical vein endothelial cells (HUVECs), the formation of capillary-like structures by these cells, and the growth of sub-intestinal blood vessels in developing Tg (fli1a: EGFP) y1/+ zebrafish embryos. Sub-toxic extract concentrations were about one-third of IC50 values in HUVECs which were established using a sulforhodamine B assay after a 3-day exposure period. Data were expressed relatively to those found with untreated controls and considered statistically significantly different from each other when p values < 0.05 (ANOVA). When compared to untreated controls, the Oenocarpus bacaba stembark extract decreased HUVEC scratch-wound areas by about 30%; increased tube length, number of branching points, and number of loops formed by HUVECs by 50-70%, and increased total sub-intestinal blood vessel length in the zebrafish embryos by about 30%. The extracts from Morinda citrifolia (leaf), Luffa acutangula (fruit juice), Momordica charantia (leaf), Psidium guajava (leaf), Cecropia peltata (branch tops), and Spondias mombin (leaf) had no statistically significant effect on any of these variables. These observations suggest that the O. bacaba sample, unlike the other samples, possessed pro-angiogenic properties which may be involved in its beneficial effects in wound healing. Future studies should more elaborately evaluate these plants in order to definitely establish their therapeutic value in wound healing.