Linked Life Data

6699871

Source:http://linkedlifedata.com/resource/pubmed/id/6699871

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1984-4-24
pubmed:abstractText
Steroid glycosides and the unique glycosidase activity of the colonic microflora form the basis of a new colon-specific drug-delivery system. Drug glycosides are hydrophilic and, thus, poorly absorbed from the small intestine. Once such a glycoside reaches the colon it can be cleaved by bacterial glycosidases, releasing the free drug to be absorbed by the colonic mucosa. This concept was illustrated with dexamethasone 21-beta-D-glucoside (1) and prednisolone 21-beta-D-glucoside (2), two prodrugs that may be useful in treating inflammatory bowel disease. Hydrolysis of the prodrugs by beta-glucosidase and fecal homogenates in vitro released the free steroids. Glucosides 1 and 2 were administered to rats intragastrically to determine when and where the free steroids were released. Unmodified dexamethasone (3) and prednisolone (4) were also given to rats intragastrically to compare absorption of the glucosides with the free steroids. Both glucosides were found to reach the rat lower intestine in 4-5 h, where they were rapidly hydrolyzed, releasing the free steroids. Delivery of steroid 3 (via glucoside 1) was more specific than that of steroid 4 (via glucoside 2): nearly 60% of an oral dose of glucoside 1 reached the cecum, whereas less than 15% of glucoside 2 reached the cecum. When free steroids 3 and 4 were administered orally, they were almost exclusively absorbed in the small intestine: less than 1% of an oral dose of each reached the cecum.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0022-2623
pubmed:author
pubmed:issnType
Print
pubmed:volume
27
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
261-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
A colon-specific drug-delivery system based on drug glycosides and the glycosidases of colonic bacteria.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't