Protective Effects of Astragaloside IV and Cycloastragenol in 6-hydroxydopamin (6-OHDA)-Induced Neurotoxicity in PC12 Cells
Astragaloside IV (AST-IV), one of the bioactive constituents of Radix Astragali, was extracted from the roots of Astragalus trojanus Bunge (Leguminosae). Cycloastragenol (CG), which is a minor metabolite mostly found in its glycosidic form, was obtained from AST-IV via hydrolysis reaction. CG has been shown to extend T cell proliferation by increasing telomarase activity showing that it may also help delay the onset of cellular aging (1). Indeed, recently, CG has been introduced to the market as a new generation antiaging molecule. Moreover our studies proved CG as an extraordinary wound healing agent (2). Although AST-IV's neuroprotective effects on Parkinson's disease was reported previously, there has been no data for CG. The aim of this study was to investigate the protective effects of AST-IV and CG on neurotoxicity induced by 6-hydroxydopamin (6-OHDA) in PC12 cells, an excepted in vitro model for Parkinson's disease. The cells were seeded on tissue culture plates for 24h. After 24 hours, they were incubated with AST-IV (0.1µM-1 fM) and CG (0.1µM-1 fM) for 30min before the insults with 200µM 6-OHDA. The cells were incubated for 24h. Cell viability and cells death were assessed by (3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide) MTT assay and lactate dehydrogenase (LDH) assay kit, respectively. AST-IV and CG inhibited the apoptosis of PC12 induced by 6-OHDA at 0.001 and 0.0001µM concentrations. On the basis of these results, we propose AST-IV and CG as potential neuroprotective agents in the treatment of Parkinson's disease.
Keywords: Astragalus, Saponin, Cycloastragenol, Astragaloside IV, Neuroprotective effect, Parkinson's disease
References: 1. Valenzuela HF et al. (2009)J Immun 182: 9–30.
2. Sevimli-Gür C et al. (2011)J Ethnopharmacol 134: 844–850.