title: Lung alterations in a rat model of diabetes mellitus: effects of antioxidant therapy.
abstract: OBJECTIVE
  To evaluate structural alterations of the lung in rats with diabetes mellitus (DM), by quantifying oxidative stress and DNA damage, as well as to determine the effects that exogenous superoxide dismutase (SOD) has on such alterations.
  
  
  METHODS
  A controlled experimental study involving 40 male Wistar rats, divided into four groups (10 animals each): control; SOD-only (without DM but treated with SOD); IDM-only (with streptozotocininduced DM but untreated); and IDM+SOD (with streptozotocin-induced DM, treated with SOD). The animals were evaluated over a 60-day period, day 0 being defined as the day on which the streptozotocin-injected animals presented glycemia > 250 mg/dL. The SOD was administered for the last 7 days of that period. At the end of the study period, samples of lung tissue were collected for histopathological analysis, evaluation of tissue oxidative stress, and assessment of DNA damage.
  
  
  RESULTS
  There were no significant differences among the groups regarding DNA damage. In the IDM-only group, there was a significant increase in the extracellular matrix and significantly greater hyperplasia of the capillary endothelium than in the SOD-only and control groups. In addition, there were significant changes in type II pneumocytes and macrophages, suggesting an inflammatory process, in the IDM-only group. However, in the IDM+SOD group, there was a reduction in the extracellular matrix, as well as normalization of the capillary endothelium and of the type II pneumocytes.
  
  
  CONCLUSIONS
  Exogenous SOD can reverse changes in the lungs of animals with induced DM.
authors.affiliation: Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Luiz Alberto
authors.initials: LA
authors.lastname: Forgiarini Junior
authors.forename: Nélson Alexandre
authors.initials: NA
authors.lastname: Kretzmann
authors.forename: Juliana
authors.initials: J
authors.lastname: Tieppo
authors.forename: Jaqueline Nascimento
authors.initials: JN
authors.lastname: Picada
authors.forename: Alexandre Simões
authors.initials: AS
authors.lastname: Dias
authors.forename: Norma Anair Possa
authors.initials: NA
authors.lastname: Marroni
mesh_terms: D000818:Animals; D004249:DNA Damage / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy* / Q000473:pathology; D016166:Free Radical Scavengers / Q000627:therapeutic use*; D015227:Lipid Peroxidation; D008168:Lung / Q000187:drug effects* / Q000473:pathology; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D013311:Streptozocin; D013482:Superoxide Dismutase / Q000494:pharmacology*; D017392:Thiobarbituric Acid Reactive Substances
chemical_list: D016166:Free Radical Scavengers; D017392:Thiobarbituric Acid Reactive Substances; D013311:Streptozocin; D013482:Superoxide Dismutase