The radioprotective potential of Centotheca lappacea (L) desv. extract in human endothelial cell

Abstract

Background: Radiation-induced vascular injury in normal tissue is a common adverse effect of radiation therapy. Radioprotectors can reduce the adverse effects of radiation-induced vascular injury. However, therapeutic applications of current radioprotectors are limited due to toxicity. Natural compounds derived from medicinal plants are less toxic and favorable for developing of radioprotectors. Centotheca lappacea has been long-term used for medicinal purposes and contains a variety of biological active compounds. Thus, the ethanolic extract from Centotheca lappacea may possibly have the potential to act as radioprotector.

Objectives: To determine radioprotective property of the ethanolic extract from Centotheca lappacea in human endothelial cell (EA.hy 926).

Materials and methods: The effect of the ethanolic extract from Centotheca lappacea on cell viability was assessed by MTT assay. Cell cycle distribution was determined by flow cytometry. Nuclei morphology was determined by fluorescence microscopy. The levels of Akt and phospho-Akt were determined by Western blot analysis.

Results: Pretreatment of cells with 0.2 μg/ml Centotheca lappacea extract for 3 hrs prior to irradiation demonstrated a radioprotective effect on EA.hy926 cells by significantly increasing cell viability and decreasing abnormal nuclei formation.Treatment of the cells with the extract in combination with radiation clearly increased the level of Akt phosphorylation. The extract is not toxic and does not interfere with cell cycle progression of EA.hy926 cells.

Conclusion: The ethanolic extract from Centotheca lappacea possesses radioprotective activity. No toxic impact and no impact on cell cycle progression in EA.hy926 cells were observed. The results indicate that Centotheca lappacea extract is an ideal resource of radioprotector for protecting radiation-induced damage to human endothelial cells.