Angiogenic Activity of β-Sitosterol in the Ischaemia/Reperfusion-Damaged Brain of Mongolian Gerbil

Aloe vera continues to be used for wound healing as a folk medicine. We previously reported that A. vera gel has angiogenic activity. In this study, we report upon the isolation of an angiogenic component beta-sitosterol from A. vera and examination of its effect upon damaged blood vessels of the Mongolian gerbil. In a chick embryo chorioallantoic membrane assay, beta-sitosterol was found to have an angiogenic effect. It enhanced new vessel formation in gerbil brains damaged by ischaemia/reperfusion, especially in the cingulated cortex and septal regions, in a dose-dependent fashion (up to 500 microg/kg, p < 0.05, n = 34 - 40). beta-Sitosterol also enhanced the expressions of proteins related to angiogenesis, namely von Willebrand factors, vascular endothelial growth factor (VEGF), VEGF receptor Flk-1, and blood vessel matrix laminin (p < 0.05, n = 6). In addition, the intraperitoneal administration of beta-sitosterol at 500 microg/kg/day for a period of 19 days significantly improved the motion recovery of ischaemia/reperfusion-damaged gerbils as assessed by rota-rod testing (p < 0.001, n = 10). Our results suggest that beta-sitosterol has therapeutic angiogenic effects on damaged blood vessels.