Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2010-11-12
pubmed:abstractText
Cycloastragenol (CAG) is the aglycone derivative of astragaloside IV which has recently been demonstrated to activate telomerase and represents a potential drug candidate for the treatment of degenerative diseases. In the present study, intestinal absorption and metabolism of CAG were examined using the Caco-2 model and liver microsomes, respectively. The results showed that CAG rapidly passes through the Caco-2 cell monolayer by passive diffusion. Four different glucuronide conjugates and two oxidized CAG metabolites were found in the apical and basolateral sides of Caco-2 monolayer, suggesting that first-pass intestinal metabolism of CAG might occur upon passage through the intestinal epithelium. CAG underwent extensive metabolism in rat and human liver microsomes with only 17.4% and 8.2%, respectively, of the starting amount of CAG remaining after 30 min of incubation. Monohydroxylation of the parent and oxidization of the hydroxylated CAG were found in the liver samples. The present study indicates that CAG is efficiently absorbed through intestinal epithelium. However, extensive first-pass hepatic metabolism would limit the oral bioavailability of this compound.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1880-0920
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
25
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
477-86
pubmed:meshHeading
pubmed-meshheading:20877137-Animals, pubmed-meshheading:20877137-Caco-2 Cells, pubmed-meshheading:20877137-Carrier Proteins, pubmed-meshheading:20877137-Diffusion, pubmed-meshheading:20877137-Egtazic Acid, pubmed-meshheading:20877137-Enterocytes, pubmed-meshheading:20877137-Enzyme Activators, pubmed-meshheading:20877137-Glucuronides, pubmed-meshheading:20877137-Humans, pubmed-meshheading:20877137-Hydroxylation, pubmed-meshheading:20877137-Intestinal Absorption, pubmed-meshheading:20877137-Intestines, pubmed-meshheading:20877137-Kinetics, pubmed-meshheading:20877137-Liver, pubmed-meshheading:20877137-Male, pubmed-meshheading:20877137-Metabolic Detoxication, Phase I, pubmed-meshheading:20877137-Metabolic Detoxication, Phase II, pubmed-meshheading:20877137-Microsomes, Liver, pubmed-meshheading:20877137-Oxidation-Reduction, pubmed-meshheading:20877137-Permeability, pubmed-meshheading:20877137-Rats, pubmed-meshheading:20877137-Sapogenins, pubmed-meshheading:20877137-Species Specificity, pubmed-meshheading:20877137-Spectrometry, Mass, Electrospray Ionization, pubmed-meshheading:20877137-Telomerase, pubmed-meshheading:20877137-Transcytosis
pubmed:year
2010
pubmed:articleTitle
In vitro intestinal absorption and first-pass intestinal and hepatic metabolism of cycloastragenol, a potent small molecule telomerase activator.
pubmed:affiliation
Biotechnology Research Institute, Department of Biochemistry, Hong Kong University of Science and Technology, Hong Kong, China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't