title: Accumulation of mitochondrial DNA mutations in human immunodeficiency virus-infected patients treated with nucleoside-analogue reverse-transcriptase inhibitors.
abstract: Nucleoside reverse-transcriptase inhibitor (NRTI) therapy for human immunodeficiency virus (HIV) infection has been associated with mitochondrial DNA (mtDNA) polymerase-gamma inhibition and subsequent mtDNA depletion. Effects on mtDNA mutation, although suggested by critical involvement of polymerase-gamma in DNA-repair reactions, are unknown. In the present study, we assessed the nature and frequency of mitochondrial genome sequence differences in peripheral-blood samples taken prior to NRTI therapy and after 6-77 mo of treatment in 16 NRTI-treated patients. Samples from 10 HIV-infected, treatment-naive control individuals were taken at similar time intervals. Single-stranded conformation polymorphism (SSCP) and DNA-sequencing analysis techniques were used to detect mitochondrial genome sequence variants between paired longitudinal samples, and heteroplasmic populations were quantified after cloning and repeat SSCP/sequencing. Of 16 individuals treated with NRTIs, 5 exhibited altered SSCP profiles associated with the development of novel heteroplasmic DNA sequence changes, whereas no SSCP pattern change within these regions was observed in the control individuals. Heteroplasmic sequence changes were distributed across four regions of the genome: the noncoding region to 12S ribosomal RNA, reduced-nicotinamide-adenine-dinucleotide dehydrogenase 1, and cytochrome oxidase subunits I and III. Of the total of 26 patients who were examined in the present study, 4 of 5 patients with detectable mtDNA sequence changes since commencement of therapy developed evidence of peripheral fat wasting (lipoatrophy) between sample intervals (P=.031). One patient, without detectable sequence changes on NRTI therapy, also developed lipoatrophy. Levels of mtDNA copies/cell in blood samples were determined by quantitative PCR for 11 of the 16 NRTI-exposed patients; 7 of these 11 patients showed reduced levels of mtDNA in blood after therapy, including all 3 patients tested with evidence of mtDNA sequence changes on therapy. These data indicate that NRTI therapy provides conditions permissive for the development of peripheral-blood mtDNA mutations in vivo.
authors.affiliation: Centre for Clinical Immunology and Biomedical Statistics, Murdoch University, Perth, Western Australia, Australia.
authors.forename: Annalise M
authors.initials: AM
authors.lastname: Martin
authors.forename: Emma
authors.initials: E
authors.lastname: Hammond
authors.forename: David
authors.initials: D
authors.lastname: Nolan
authors.forename: Craig
authors.initials: C
authors.lastname: Pace
authors.forename: Marion
authors.initials: M
authors.lastname: Den Boer
authors.forename: Louise
authors.initials: L
authors.lastname: Taylor
authors.forename: Hannah
authors.initials: H
authors.lastname: Moore
authors.forename: Olga Patricia
authors.initials: OP
authors.lastname: Martinez
authors.forename: Frank T
authors.initials: FT
authors.lastname: Christiansen
authors.forename: Simon
authors.initials: S
authors.lastname: Mallal
mesh_terms: D001483:Base Sequence; D004252:DNA Mutational Analysis; D000074002:DNA Polymerase gamma; D017931:DNA Primers; D004272:DNA, Mitochondrial / Q000187:drug effects / Q000235:genetics*; D004275:DNA, Ribosomal / Q000235:genetics; D004259:DNA-Directed DNA Polymerase / Q000235:genetics*; D015658:HIV Infections / Q000188:drug therapy* / Q000235:genetics*; D006801:Humans; D019259:Lamivudine / Q000627:therapeutic use; D008969:Molecular Sequence Data; D016296:Mutagenesis; D019384:Nucleic Acid Synthesis Inhibitors; D018807:Polymorphism, Single-Stranded Conformational; D012335:RNA, Ribosomal / Q000235:genetics; D018894:Reverse Transcriptase Inhibitors / Q000009:adverse effects*; D018119:Stavudine / Q000627:therapeutic use; D013997:Time Factors
chemical_list: D017931:DNA Primers; D004272:DNA, Mitochondrial; D004275:DNA, Ribosomal; D019384:Nucleic Acid Synthesis Inhibitors; D012335:RNA, Ribosomal; C075526:RNA, ribosomal, 12S; D018894:Reverse Transcriptase Inhibitors; D019259:Lamivudine; D018119:Stavudine; D000074002:DNA Polymerase gamma; D004259:DNA-Directed DNA Polymerase