Anti-Angiogenic Effects of Pomegranate Peel Extract (Punica Granatum L.) on Human Umbilical Vein Endothelial Cells

Angiogenesis, the process of forming new blood vessels from previously existing vessels, plays an important role in the development of various physiological and pathological phenomena including tumor growth. Currently, angiogenesis inhibition is considered as a supplement for the conventional cancer treatments like chemotherapy and radiation therapy. This study aimed to investigate the anti-angiogenesis effects of pomegranate peel extract.

Hydroalcoholic extract was prepared from the peel of black pomegranate (from Yazd, Iran). Afterwards, 1×105 human umbilical vein endothelial cells (HUVEC) were cultured on Matrigel and treated with different doses of extract (10, 100, and 1000 μg/ml) for 24 hours. The cells were then stained with calcein and investigated by fluorescent microscopy. The obtained images were analyzed by AngioQuant software. Data analysis was performed in SPSS15 using Kruskal-Wallis and one way analysis of variance (ANOVA).

Significant dose-dependent reductions were detected in the length, size, and number of junctions of the tubes at all 3 doses of pomegranate peel extract. The most significant anti-angiogenic effect was observed as the dose 1000 µg/ml. Compared to the other 2 doses, this dose could better reduce tube size (19.46 ± 2.61 vs. 20186 ± 1627 at 10 μg/ml and 11195.67 ± 5454 at 100 μg/ml) and tube length (66 ± 12 vs. 5602 ± 1108 at 10 μg/ml and 3084.4 ± 1541 at 100 μg/ml). Furthermore, there were no junctions at 1000 µg/ml while the junction formation was 93.67 ± 50 and 26 ± 13 at 10 and 100 μg/ml, respectively.

Our results indicated anti-angiogenic effects of pomegranate peel extract. It can thus be considered as a candidate for the inhibition of angiogenesis in pathologic angiogenesis-dependent diseases.