title: Mitochondrial assessment in asymptomatic HIV-infected paediatric patients on HAART.
abstract: BACKGROUND
  HAART can cause mitochondrial DNA (mtDNA) depletion, which may lead to mitochondrial dysfunction. We aimed to determine whether mtDNA and mitochondrial function abnormalities are present in peripheral blood mononuclear cells from asymptomatic HIV-infected children.
  
  
  METHODS
  A cross-sectional study in peripheral blood mononuclear cells was performed in 47 asymptomatic (free from any HIV- or AIDS-related active condition or HAART-related toxicity), HIV-infected, HAART-treated children and adolescents and 27 uninfected healthy paediatric patients. We measured mtDNA and mitochondrial RNA (mtRNA) content by quantitative real-time PCR. Mitochondrial respiratory chain enzymatic activity of complex-IV (CIV) and mitochondrial mass (estimated by citrate synthase) were measured spectrophotometrically, and CIV protein subunit content was measured with western blot analysis.
  
  
  RESULTS
  A reduction in mtDNA levels was observed in HIV-infected children compared with controls (mean ± sem 4.47 ± 0.31 and 5.82 ± 0.48, respectively; 23% depletion; P=0.018), whereas similar levels of mtRNA, CIV protein subunit content and enzymatic activity were found in the two groups. These findings remained unaltered after considering mitochondrial abundance. Among HIV-infected children, mtDNA levels did not correlate with viral load, CD4(+) T-cell counts or lactataemia at the time of assessment. No differences were observed when current or past use of individual antiretroviral drugs or HAART regimens were taken into account.
  
  
  CONCLUSIONS
  Depletion in mtDNA from asymptomatic HIV-infected children did not lead to differences in mtRNA levels or mitochondrially-encoded CIV proteins, nor to CIV dysfunction. This may be explained by homeostatic-compensatory mechanisms at the transcription level or by the mild depletion we observed.
authors.affiliation: Mitochondrial Functionalism Laboratory, Universitat de Barcelona, IDIBAPS, Hospital Clínic, Barcelona, Spain.
authors.forename: Constanza
authors.initials: C
authors.lastname: Morén
authors.forename: Antoni
authors.initials: A
authors.lastname: Noguera-Julian
authors.forename: Núria
authors.initials: N
authors.lastname: Rovira
authors.forename: Glòria
authors.initials: G
authors.lastname: Garrabou
authors.forename: Mireia
authors.initials: M
authors.lastname: Nicolàs
authors.forename: Francesc
authors.initials: F
authors.lastname: Cardellach
authors.forename: Esteban
authors.initials: E
authors.lastname: Martínez
authors.forename: Emília
authors.initials: E
authors.lastname: Sánchez
authors.forename: Oscar
authors.initials: O
authors.lastname: Miró
authors.forename: Clàudia
authors.initials: C
authors.lastname: Fortuny
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000150:complications / Q000188:drug therapy / Q000378:metabolism; D000293:Adolescent; D019380:Anti-HIV Agents / Q000378:metabolism / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active / Q000009:adverse effects*; D058070:Asymptomatic Diseases; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004272:DNA, Mitochondrial / Q000097:blood* / Q000235:genetics; D005260:Female; D006678:HIV / Q000187:drug effects; D015658:HIV Infections / Q000097:blood / Q000150:complications / Q000188:drug therapy*; D006679:HIV Seropositivity / Q000150:complications / Q000188:drug therapy* / Q000378:metabolism; D006776:Hospitals, Pediatric; D006785:Hospitals, University; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008297:Male; D008928:Mitochondria / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism; D009000:Monocytes / Q000378:metabolism
chemical_list: D019380:Anti-HIV Agents; D004272:DNA, Mitochondrial; D024101:Mitochondrial Proteins