title: Monitoring abacavir bioactivation in humans: screening for an aldehyde metabolite.
abstract: The anti-HIV drug abacavir is associated with idiosyncratic hypersensitivity reactions and cardiotoxicity. Although the mechanism underlying abacavir-toxicity is not fully understood, drug bioactivation to reactive metabolites may be involved. This work was aimed at identifying abacavir-protein adducts in the hemoglobin of HIV patients as biomarkers of abacavir bioactivation and protein modification. The protocol received prior approval from the Hospital Ethics Committee, patients gave their written informed consent and adherence was controlled through a questionnaire. Abacavir-derived Edman adducts with the N-terminal valine of hemoglobin were analyzed by an established liquid chromatography-electrospray ionization-tandem mass spectrometry method. Abacavir-valine adducts were detected in three out of ten patients. This work represents the first evidence of abacavir-protein adduct formation in humans. The data confirm the ability of abacavir to modify self-proteins and suggest that the molecular mechanism(s) of some abacavir-induced adverse reactions may require bioactivation.
authors: Centro de Estudos de Doenças Crónicas (CEDOC), Faculdade de Ciências Médicas (FCM), Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal.
authors: Nádia M
authors: NM
authors: Grilo
authors: Alexandra M M
authors: AM
authors: Antunes
authors: Umbelina
authors: U
authors: Caixas
authors: Aline T
authors: AT
authors: Marinho
authors: Catarina
authors: C
authors: Charneira
authors: M
authors: M
authors: Conceição Oliveira
authors: Emília C
authors: EC
authors: Monteiro
authors: M
authors: M
authors: Matilde Marques
authors: Sofia A
authors: SA
authors: Pereira
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000447:Aldehydes / Q000378:metabolism*; D019380:Anti-HIV Agents / Q000009:adverse effects* / Q000378:metabolism* / Q000493:pharmacokinetics / Q000627:therapeutic use; D015415:Biomarkers / Q000097:blood / Q000378:metabolism; D001711:Biotransformation; D015224:Dideoxynucleosides / Q000009:adverse effects* / Q000378:metabolism* / Q000493:pharmacokinetics / Q000627:therapeutic use; D016903:Drug Monitoring; D005260:Female; D015658:HIV Infections / Q000097:blood / Q000188:drug therapy; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D011506:Proteins / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry; D000099227:Abacavir
chemical_list: D000447:Aldehydes; D019380:Anti-HIV Agents; D015415:Biomarkers; D015224:Dideoxynucleosides; D006454:Hemoglobins; D011506:Proteins; D000099227:Abacavir