In vitro effects of Aloe vera extracts on cellular proliferation after injury and other measures of wound-healing in human umbilical vein endothelial cells

CAROLINE INGLES; KAN HE; ISABEL GARCIA-TORNADU; MARÍA MARTA BONAVENTURA; VICTORIA LUX-LANTOS

Congreso; IUNS 21st International Congress of Nutrition; 2017

Several published clinical trials have evaluated effects of Aloe vera intake on gastrointestinal function; however, these effects have not been well studied in humans under controlled conditions. Some maintain that A. vera gel has the ability, both in animals and humans, to cure gastric ulcers. The putative anti-ulcer activity of A. vera has been attributed to several possible mechanisms, including anti-inflammatory properties, healing effects, mucus-stimulatory effects and a modulation of gastric secretions.A necessary part of the healing of any wound, including gastric ulcers, is vascularization of the wound clot and granulation tissue. The aim of this work was to evaluate the effects of two A. vera extracts on different parameters of angiogenesis evaluated in human umbilical vein endothelial cells (HUVECs).A. vera whole leaf was processed to yield two different extracts: an alcohol-soluble fraction (FS) and an alcohol-insoluble fraction (FI). The HUVEC line was used as in previous works. The proliferation of HUVECs was measured with the Cell Proliferation Kit I. The extracts were added in three concentrations: 10, 50 or 100 ug/ml. Secretion and intracellular concentration of Vascular endothelial growth factor (VEGF) (HumanVEGF ELISA) and Hypoxia-inducible factor 1-alpha (HIF1α) (Human HIF1alpha ELISA Kit) were determined. HUVEC cultures were mechanically wounded and then incubated with the FI or FS extracts. Cell migration was monitored at initial wounding (t0) and t 9h under a phase-contrast microscope. Images were quantified using Image J software. Data was analyzed by ANOVA, followed by Duncan post-hoc test. Both FS and FI induced significant cell proliferation [Fig. 1]. Proliferation was seen at all three doses tested for FI, and the two higher doses for FS. No significant changes in secretion or intracellular levels of VEGF and HIF1α were observed [Figs. 2 and 3]. After 9h incubation, a significant improvement of wound healing as shown by cellular migration was induced by FS and FI at all concentrations tested [Fig. 4]. In sum, analysis of the effects of the FS and FI A. vera extracts on several aspects of endothelial function in HUVECs showed positive effects on endothelial cell proliferation and migration associated with wound healing.