title: Evaluation of the effect of Withania somnifera root extracts on cell cycle and angiogenesis.
abstract: In the Indian System of Medicine, the medicinal plant, Withania somnifera Dunal (Solanaceae) finds application for numerous ailments including cancer. This study explores the mechanism(s) underlying this property. The hydroalcoholic extract of the roots (WS) was partitioned between chloroform (WS-chloroform) and water (WS-water). Further, WS-chloroform was fractionated (A1-A12) by reverse-phase column chromatography and their withanolide content was quantified by high-performance liquid chromatography (HPLC). Preliminarily, the anti-proliferative activity of all the extracts and fractions was screened against human laryngeal carcinoma (Hep2) cells by microculture tetrazolium assay (MTT). Two extracts (WS and WS-chloroform) and three fractions (A4, A5 and A6) negatively affected Hep2 viability at the concentration of 25 microg/ml and these were further investigated pharmacologically. Flow cytometry revealed cell cycle block and accumulation of hypoploid (sub G1) cells as the mode of anti-proliferative activity of all but A4. Their anti-angiogenic potential was investigated by a chickchorio-allantoic membrane (CAM) wherein a significant inhibition (p<0.0001) of vascular endothelium growth factor (VEGF), induced neovascularization was recorded. The effect was confirmed in vivo by mouse sponge implantation method. These findings suggest that the roots of Withania somnifera possess cell cycle disruption and anti-angiogenic activity, which may be a critical mediator for its anti-cancer action.
authors.affiliation: Department of Pharmacology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India.
authors.forename: Rajani
authors.initials: R
authors.lastname: Mathur
authors.forename: Suresh K
authors.initials: SK
authors.lastname: Gupta
authors.forename: Neeta
authors.initials: N
authors.lastname: Singh
authors.forename: Sandeep
authors.initials: S
authors.lastname: Mathur
authors.forename: Vinod
authors.initials: V
authors.lastname: Kochupillai
authors.forename: Thirumurthy
authors.initials: T
authors.lastname: Velpandian
mesh_terms: D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D002453:Cell Cycle / Q000187:drug effects*; D045744:Cell Line, Tumor; D006801:Humans; D008297:Male; D051379:Mice; D010936:Plant Extracts / Q000494:pharmacology*; D018517:Plant Roots / Q000737:chemistry*; D032341:Withania / Q000737:chemistry
chemical_list: D020533:Angiogenesis Inhibitors; D000972:Antineoplastic Agents, Phytogenic; D010936:Plant Extracts