Antiretroviral (ARV) drug therapy, given during pregnancy for prevention of mother-to-child transmission of HIV-1, induces fetal mitochondrial dysfunction in some children, and the persistence/reversibility of that dysfunction is unclear. We followed Erythrocebus patas (patas) monkey offspring for up to 3 years of age (similar in development to a 15 year old human) after exposure of the dams to human-equivalent in utero ARV exposure protocols. Pregnant patas dams (3-5/exposure group) were given zidovudine (AZT) / lamivudine (3TC) / abacavir (ABC), or AZT / 3TC / nevirapine (NVP), for the last 10 weeks (50%) of gestation. Infants grown for 1 and 3 years also received drug for the first 6 weeks of life. In offpsring at birth, 1 year and 3 years of age, mitochondrial morphology (electron microscopy), was compromised compared to the unexposed controls. Mitochondrial DNA (mtDNA) was depleted in hearts of patas exposed to AZT/3TC/NVP at all ages (p less than 0.05), but not in those exposed to AZT/3TC/ABC at any age. Compared to unexposed controls, mitochondrial reserve capacity oxygen consumption rate (OCR by Seahorse) in cultured bone marrow mesenchymal fibroblasts from 3 year old patas offspring, was 50% reduced in AZT/3TC/ABC-exposed patas (p less than 0.01), but not in AZT/3TC/NVP-exposed patas. Therefore, patas exposed in utero and 6 wk after birth sustain persistent mitochondrial dysfunction as a result of ARV drug exposures. This duration of mitochondrial toxicity is consistent with the findings of persistent genotoxicity, including centrosomal amplification, micronuclei and aneuploidy in bone marrow of the same animals. Primary cilia arise from the centrosome, and communicate stimuli from the environment to the interior of the cell. In this study the aneugen AZT was used to study cilium formation in retinal epithelial (RPE) cells. Cells were exposed continuously to 0 or 20 microM AZT for 4 days, the drug was removed, and cells were cultured for 48 hr. Anti-acetylated tubulin antibody was used to visualize cilia, anti-pericentrin antibody to visualize centrosomes, and DAPI to stain DNA. Scoring of 100 cells/group revealed significant increases in both centrosomal amplification (CA) and the rate of cells with multiple cilia, in exposed vs. unexposed cells. Therefore, increased rates of ciliogenesis occur, along with the genotoxic end point CA, in RPE cells exposed to the aneugen AZT.
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