title: Pharmacokinetics, metabolism, and excretion of cycloastragenol, a potent telomerase activator in rats.
abstract: 1. The objective of this study was to investigate the pharmacokinetics, excretion, and metabolic fate of cycloastragenol (CA) in rats. 2. An LC-MS method was developed and used to quantify CA in biological samples. Rats were orally administrated with CA at 10, 20, and 40 mg/kg or intravenously administrated at 10 mg/kg to determine pharmacokinetic parameters of CA. For excretion experiment, urine, feces, and bile were collected at 24 h after oral administration (40 mg/kg), also at 12 h after intravenous administration (10 mg/kg). An LC-MS/MS method was developed to identify the metabolites of CA. 3. The results showed that the oral bioavailability of CA was about 25.70% at 10 mg/kg. CA was excreted through bile and feces and eliminated predominantly by the kidney in rats. It also might exist an enterohepatic circulation of CA in rats. CA could be metabolized widely in vivo in rat, seven, six, and one phase I metabolites were found in feces, urine, and bile samples respectively, but no phase II metabolite was found. 4. In summary, this study defined pharmacokinetics characteristics of CA, described its excretion, and established its in vivo metabolism in rats.
authors.affiliation: a School of Chinese Materia Medica, Beijing University of Chinese Medicine , Beijing , China.
authors.forename: Peng-Kai
authors.initials: PK
authors.lastname: Ma
authors.affiliation: a School of Chinese Materia Medica, Beijing University of Chinese Medicine , Beijing , China.|b National Engineering Research Center for Marine Drugs, Ocean University of China , Qingdao , China , and.
authors.forename: Bao-Hong
authors.initials: BH
authors.lastname: Wei
authors.affiliation: c Research Center for Life Science and Environmental Sciences, Haerbin University of Commerce , Haerbin , China.
authors.forename: Yan-Ling
authors.initials: YL
authors.lastname: Cao
authors.affiliation: a School of Chinese Materia Medica, Beijing University of Chinese Medicine , Beijing , China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Miao
authors.affiliation: a School of Chinese Materia Medica, Beijing University of Chinese Medicine , Beijing , China.
authors.forename: Ning
authors.initials: N
authors.lastname: Chen
authors.affiliation: a School of Chinese Materia Medica, Beijing University of Chinese Medicine , Beijing , China.
authors.forename: Chang-E
authors.initials: CE
authors.lastname: Guo
authors.affiliation: a School of Chinese Materia Medica, Beijing University of Chinese Medicine , Beijing , China.
authors.forename: Hong-Ying
authors.initials: HY
authors.lastname: Chen
authors.affiliation: a School of Chinese Materia Medica, Beijing University of Chinese Medicine , Beijing , China.
authors.forename: Yu-Jie
authors.initials: YJ
authors.lastname: Zhang
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001646:Bile / Q000378:metabolism; D001826:Body Fluids; D002851:Chromatography, High Pressure Liquid; D020536:Enzyme Activators / Q000378:metabolism*; D005243:Feces; D051381:Rats; D012502:Sapogenins / Q000378:metabolism*; D053719:Tandem Mass Spectrometry; D019098:Telomerase / Q000378:metabolism; D014018:Tissue Distribution
chemical_list: D020536:Enzyme Activators; D012502:Sapogenins; D019098:Telomerase; C061014:cycloastragenol
keywords: Cycloastragenol; excretion; in rat; metabolites; pharmacokinetics