对接受基于齐多夫定的疗法预防HIV-1感染的未感染婴儿脐带组织中线粒体tRNA基因及其侧翼区域进行突变分析。

Mutational analysis of the mitochondrial tRNA genes and flanking regions in umbilical cord tissue from uninfected infants receiving AZT-based therapies for prophylaxis of HIV-1.

作者信息

Torres Salina M, Walker Dale M, McCash Consuelo L, Carter Meghan M, Ming Jessica, Cordova Edmund M, Pons Rachel M, Cook Dennis L, Seilkop Steven K, Copeland William C, Walker Vernon E

机构信息

Lovelace Respiratory Research Institute, Albuquerque, New Mexico, USA.

出版信息

Environ Mol Mutagen. 2009 Jan;50(1):10-26. doi: 10.1002/em.20433.

DOI:10.1002/em.20433

PMID:19031409

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC3191876/

Abstract

A sensitive vertical denaturing gradient gel electrophoresis (DGGE) method, using 13 unipolar psoralen-clamped PCR primer pairs, was developed for detecting sequence variants in the 22 tRNA genes and flanking regions (together spanning approximately 21%) of the human mitochondrial genome. A study was conducted to determine (i) if mitochondrial DNA (mtDNA) polymorphisms and/or mutations were detectable in healthy newborns and (ii) if prepartum 3'-azido-2',3'-dideoxythymidine (AZT) based HIV-1 prophylaxis was associated with significant increases in mtDNA mutations and changes in the degree of heteroplasmy of sequence variants in uninfected infants born to HIV-1-infected mothers. DGGE analysis of umbilical cord tissue (where vascular endothelium and smooth muscle cells are the major source of mtDNA) showed that mtDNA sequence variants were significantly elevated by threefold in AZT-treated infants compared with unexposed controls (P < 0.001), with 24 changes observed in 19/52 (37%) treated newborns (averaging 0.46 changes/subject) versus only eight changes found in 7/55 (13%) unexposed newborns (averaging 0.15 changes/subject). Six distinct sequence variants occurring in unexposed controls were predominately synonymous and homoplasmic, representing previously reported polymorphisms. Uninfected infants exposed to a combination of AZT and 2',3'-dideoxy-3'-thiacytidine and "maternal HIV-1" had a significant shift in the spectrum of mutations (P = 0.04) driven by increases in nonsynonymous heteroplasmic sequence variants at polymorphic sites (10 distinct variants) and novel sites (four distinct variants). While the weight of evidence suggests that prepartum AZT-based prophylaxis produces mtDNA mutations, additional research is needed to determine the degree to which fetal responses to maternal HIV-1 infection, in the absence of antiretroviral treatment, contribute to prenatal mtDNA mutagenesis.

摘要

开发了一种灵敏的垂直变性梯度凝胶电泳（DGGE）方法，该方法使用13对单极补骨脂素夹钳PCR引物对，用于检测人类线粒体基因组中22个tRNA基因及其侧翼区域（共约占21%）的序列变异。开展了一项研究以确定：（i）健康新生儿中是否可检测到线粒体DNA（mtDNA）多态性和/或突变；（ii）基于3'-叠氮-2',3'-双脱氧胸苷（AZT）的HIV-1产前预防措施是否与感染HIV-1的母亲所生未感染婴儿的mtDNA突变显著增加以及序列变异的异质性程度变化相关。对脐带组织（其中血管内皮和平滑肌细胞是mtDNA的主要来源）进行DGGE分析显示，与未暴露的对照组相比，接受AZT治疗的婴儿的mtDNA序列变异显著增加了三倍（P < 0.001），在19/52（37%）接受治疗的新生儿中观察到24处变化（平均每个受试者0.46处变化），而在7/55（13%）未暴露的新生儿中仅发现8处变化（平均每个受试者0.15处变化）。未暴露对照组中出现的6种不同序列变异主要是同义且同质的，代表先前报道的多态性。暴露于AZT和2',3'-双脱氧-3'-硫代胞苷联合用药及“母体HIV-1”的未感染婴儿，其突变谱发生了显著变化（P = 0.04），这是由多态性位点（10种不同变异）和新位点（4种不同变异）处非同义异质序列变异增加所驱动。虽然现有证据表明基于AZT的产前预防措施会产生mtDNA突变，但仍需要进一步研究以确定在未进行抗逆转录病毒治疗的情况下，胎儿对母体HIV-1感染的反应在多大程度上导致产前mtDNA诱变。