title: 3-O-beta-D-Galactopyranoside of quercetin as an active principle from high altitude Podophyllum hexandrum and evaluation of its radioprotective properties.
abstract: The aqueous-ethanolic extract (AEE) of high altitude Podophyllum hexandrum has earlier been reported to render a radioprotective effect against lethal gamma radiation in in vitro model. AEE has also been reported to possess metal chelating and DNA protecting properties. The present study was undertaken to isolate and characterize the bioactive principle present in AEE and investigate its role in radiation protection. A novel molecule was found to be present in AEE and was assigned as 3-O-beta-D-galactoside of quercetin by acid hydrolysis, LC-MS, LC-APCI-MS/MS and 13C NMR spectra. Various biological activities were investigated at in vitro level. The antioxidant potential of AEE in lipid and aqueous phase was determined against numerous stresses. AEE was found to be significantly (p < 0.05) protective, i.e., against Fe2+ and Cu2+-induced linoleic acid degradation, respectively. Radiation-induced lipid oxidation studies revealed that AEE maximally works at a [lignan]/0.25 kGy ratio 400 (ratio of concentration of AEE divided by the radiation dose, i.e., 0.25 kGy) and no drug-induced lipid oxidation at all concentrations tested was found. In a time-dependent study, total antioxidant activity was maximally exhibited at 1 mg/ml. The site-specific and non-site-specific deoxyribose degradation assay exhibited a dose-dependant hydroxyl scavenging potential of AEE (0.05-500 microg/ml). The anti-lipid peroxidation ability of AEE against radiation (0.25 kGy)-induced lipid peroxidation was higher in case of neural tissue homogenate as compared to kidney homogenate [activity ratio: 0.039 (brain) < 0.24 (kidney)]. The protein protection study using bovine serum albumin was also done for two time intervals (2 h and 4 h) and significant (p < 0.05) protection was observed at 500 microg/ml (> 97%). This study implies that 3-O-beta-D-galactoside present in AEE renders radioprotection by protecting lipids, proteins in renal and neural model system against supra-lethal (0.25 kGy) gamma radiation.
authors.affiliation: Department of Radiation Biology, Institute of Nuclear Medicine and Allied Sciences, Delhi, India.
authors.forename: Raman
authors.initials: R
authors.lastname: Chawla
authors.forename: Rajesh
authors.initials: R
authors.lastname: Arora
authors.forename: Ravinder K
authors.initials: RK
authors.lastname: Sagar
authors.forename: Shikha
authors.initials: S
authors.lastname: Singh
authors.forename: Satish C
authors.initials: SC
authors.lastname: Puri
authors.forename: Raj
authors.initials: R
authors.lastname: Kumar
authors.forename: Surender
authors.initials: S
authors.lastname: Singh
authors.forename: Ashok K
authors.initials: AK
authors.lastname: Sharmaa
authors.forename: Jagdish
authors.initials: J
authors.lastname: Prasada
authors.forename: Haider A
authors.initials: HA
authors.lastname: Khan
authors.forename: Rakesh Kumar
authors.initials: RK
authors.lastname: Sharma
authors.forename: Kanaya Lal
authors.initials: KL
authors.lastname: Dhar
authors.forename: Michael
authors.initials: M
authors.lastname: Spiteller
authors.forename: Ghulam Nabi
authors.initials: GN
authors.lastname: Qazi
mesh_terms: D000531:Altitude; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D001921:Brain / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D016166:Free Radical Scavengers; D005697:Galactosides / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D005720:Gamma Rays; D007194:India; D007668:Kidney / Q000378:metabolism; D015227:Lipid Peroxidation / Q000528:radiation effects*; D008297:Male; D051379:Mice; D008958:Models, Molecular; D010936:Plant Extracts / Q000302:isolation & purification*; D011035:Podophyllum / Q000737:chemistry*; D011794:Quercetin / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D011837:Radiation-Protective Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D012710:Serum Albumin, Bovine / Q000187:drug effects
chemical_list: D000975:Antioxidants; D016166:Free Radical Scavengers; D005697:Galactosides; D010936:Plant Extracts; D011837:Radiation-Protective Agents; C508165:quercetin-3-O-beta-D-galactopyranoside; D012710:Serum Albumin, Bovine; D011794:Quercetin