title: Variability in DDT-induced apoptosis in Mexican indigenous populations.
abstract: BACKGROUND
  In previous studies, we showed that DDT and its metabolites are able to induce apoptosis of peripheral blood mononuclear cells (PBMC) "in vitro" and "in vivo", by a mechanism involving oxidative stress.
  
  
  OBJECTIVE
  The objective of this study was to evaluate the mechanism by which DDT induces apoptosis in PBMC in children exposed to DDT and its metabolites.
  
  
  METHODS
  Eligibility criteria included children who: (1) have lived in the selected community since birth, (2) were between 6 and 14 years of age at the time of the study, (3) had not been exposed to medicaments or tobacco smoke, and (4) had had no infectious diseases in the month prior to the study. DDT and its metabolites were quantified using gas chromatography with an electron capture detector, PBMC apoptosis was measured using the TUNEL assay, DNA damage and oxidative damage were studied using the comet assay.
  
  
  RESULTS
  Apoptosis correlated to DDE exposure (p=0.040), as previously found. DNA damage also correlated to DDT (p=0.005) and DDE (p=0.004) levels. However, neither exposure to DDT or DDE and oxidative damage, nor oxidative damage and apoptosis, were significantly correlated. Children living in Lacanja, Chiapas, one of the communities studied in this work, had the highest levels of exposure to DDT and its metabolites, yet had the lowest percentage of apoptosis.
  
  
  CONCLUSIONS
  Resistance to DDE-induced apoptosis was found in children from one community. Further studies are needed in order to understand the mechanism involved in this apoptosis resistance.
authors: Departamento de Toxicología Ambiental, Facultad de Medicina, Universidad Autónoma de San Luis Potosí, Mexico.
authors: Iván N
authors: IN
authors: Pérez-Maldonado
authors: Francisco J
authors: FJ
authors: Pérez-Vázquez
authors: Octavio
authors: O
authors: Gaspar-Ramírez
authors: Roberto
authors: R
authors: González-Amaro
authors: Fernando
authors: F
authors: Díaz-Barriga
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D003634:DDT / Q000633:toxicity*; D006801:Humans; D008800:Mexico
chemical_list: D003634:DDT