Linked Life Data

10604941

Source:http://linkedlifedata.com/resource/pubmed/id/10604941

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2000-1-27
pubmed:abstractText
Phosphorothioate antisense oligodeoxynucleotides are novel therapeutic agents designed to selectively and specifically inhibit production of various disease-related gene products. In vivo pharmacokinetic experiments indicate that these molecules are widely distributed in many species, with the majority of oligomers accumulating within liver and kidney. To better understand the metabolism of these agents, we studied the stability of several phosphorothioate oligodeoxynucleotides, their congeners, and second generation oligomer chemistries in rat liver homogenates. To examine metabolism, background nuclease activity was characterized in whole liver homogenates by using ISIS 1049, a 21-mer phosphodiester oligodeoxynucleotide. Nuclease activity could readily be detected in liver homogenates. Under optimized conditions, the predominant enzymatic activity was 3'-exonucleolytic and could be influenced by pH and ionic conditions. However, in addition to 3' exonucleases, 5' exo- and endonuclease activities were also observed. Our data indicate that metabolism of phosphorothioate oligodeoxynucleotides was more complex than that of phosphodiesters for many reasons, including phosphorothioate oligodeoxynucleotide inhibition of nucleases and the presence of R(p) and S(p) stereoisomers. The rate of phosphorothioate metabolism also appeared to be influenced by sequence, with pyrimidine-rich compounds being metabolized to a greater extent than purine-rich oligomers. Other factors affecting stability included oligomer chemistry and length. Concomitant experiments performed in rats dosed systemically with the same compounds mimic the activities seen in vitro and suggest that this liver homogenate system is a valuable model with which to study the mechanism of metabolism of antisense oligonucleotides.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0022-3565
pubmed:author
pubmed:issnType
Print
pubmed:volume
292
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
140-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Metabolism of antisense oligonucleotides in rat liver homogenates.
pubmed:affiliation
Isis Pharmaceuticals, Inc., Carlsbad Research Center, Carlsbad, CA 92008, USA. rcrooke@isisph.com
pubmed:publicationType
Journal Article, Comparative Study, In Vitro