Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2009-10-23
pubmed:abstractText
Primaquine, an 8-aminoquinoline, is the drug of choice for radical cure of relapsing malaria. Use of primaquine is limited due to its hemotoxicity, particularly in populations with glucose-6-phosphate dehydrogenase deficiency [G6PD(-)]. Biotransformation appears to be central to the anti-infective and hematological toxicities of primaquine, but the mechanisms are still not well understood. Metabolic studies with primaquine have been hampered due to the reactive nature of potential hemotoxic metabolites. An in vitro metabolism-linked hemotoxicity assay has been developed. Co-incubation of the drug with normal or G6PD(-) erythrocytes, microsomes or recombinant cytochrome P(450) (CYP) isoforms has allowed in situ generation of potential hemotoxic metabolite(s), which interact with the erythrocytes to generate hemotoxicity. Methemoglobin formation, real-time generation of reactive oxygen intermediates (ROIs) and depletion of reactive thiols were monitored as multiple biochemical end points for hemotoxicity. Primaquine alone did not produce any hemotoxicity, while a robust increase was observed in methemoglobin formation and generation of ROIs by primaquine in the presence of human or mouse liver microsomes. Multiple CYP isoforms (CYP2E1, CYP2B6, CYP1A2, CYP2D6 and CYP3A4) variably contributed to the hemotoxicity of primaquine. This was further confirmed by significant inhibition of primaquine hemotoxicity by the selective CYP inhibitors, namely thiotepa (CYP2B6), fluoxetine (CYP2D6) and troleandomycin (CYP3A4). Primaquine caused similar methemoglobin formation in G6PD(-) and normal human erythrocytes. However, G6PD(-) erythrocytes suffered higher oxidative stress and depletion of thiols than normal erythrocytes due to primaquine toxicity. The results provide significant insights regarding CYP isoforms contributing to hemotoxicity and may be useful in controlling toxicity of primaquine to increase its therapeutic utility.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Antimalarials, http://linkedlifedata.com/resource/pubmed/chemical/Cytochrome P-450 Enzyme System, http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Fluoxetine, http://linkedlifedata.com/resource/pubmed/chemical/Glucosephosphate Dehydrogenase, http://linkedlifedata.com/resource/pubmed/chemical/Isoenzymes, http://linkedlifedata.com/resource/pubmed/chemical/Methemoglobin, http://linkedlifedata.com/resource/pubmed/chemical/Primaquine, http://linkedlifedata.com/resource/pubmed/chemical/Reactive Oxygen Species, http://linkedlifedata.com/resource/pubmed/chemical/Sulfhydryl Compounds, http://linkedlifedata.com/resource/pubmed/chemical/Thiotepa, http://linkedlifedata.com/resource/pubmed/chemical/Troleandomycin
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1096-0333
pubmed:author
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
241
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
14-22
pubmed:meshHeading
pubmed-meshheading:19616568-Animals, pubmed-meshheading:19616568-Antimalarials, pubmed-meshheading:19616568-Cytochrome P-450 Enzyme System, pubmed-meshheading:19616568-Enzyme Inhibitors, pubmed-meshheading:19616568-Erythrocytes, pubmed-meshheading:19616568-Female, pubmed-meshheading:19616568-Fluoxetine, pubmed-meshheading:19616568-Glucosephosphate Dehydrogenase, pubmed-meshheading:19616568-Humans, pubmed-meshheading:19616568-Isoenzymes, pubmed-meshheading:19616568-Male, pubmed-meshheading:19616568-Methemoglobin, pubmed-meshheading:19616568-Mice, pubmed-meshheading:19616568-Mice, Inbred ICR, pubmed-meshheading:19616568-Microsomes, Liver, pubmed-meshheading:19616568-Oxidative Stress, pubmed-meshheading:19616568-Primaquine, pubmed-meshheading:19616568-Reactive Oxygen Species, pubmed-meshheading:19616568-Sulfhydryl Compounds, pubmed-meshheading:19616568-Thiotepa, pubmed-meshheading:19616568-Troleandomycin
pubmed:year
2009
pubmed:articleTitle
Cytochrome P(450)-dependent toxic effects of primaquine on human erythrocytes.
pubmed:affiliation
National Center for Natural Products Research, School of Pharmacy, University of Mississippi, University MS 38677, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't