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   Arch Biochem Biophys 1999 Dec 1;372(1):37-43
   
Dose-dependent increase of oxidative damage in the testes of rats subjected to
acute iron overload.

    Lucesoli F, Caligiuri M, Roberti MF, Perazzo JC, Fraga CG
    
   School of Pharmacy and Biochemistry, University of Buenos Aires,
   Buenos Aires, Argentina.
   
   This study describes the in vivo response of rat testes to acute iron
   overload. Male Wistar rats (250-300 g) were injected ip with iron
   dextran at doses of 250 (Fe250), 500 (Fe500), or 1000 mg/kg body wt
   (Fe1000) or with saline (C). Parameters of oxidative stress and iron
   toxicity were measured 20 h after injection. Total iron content was
   3.5-, 5.3-, and 10.4-fold higher in the Fe250, Fe500, and Fe1000
   groups, respectively, compared to controls (320 +/- 22 nmol/g tissue).
   Histological studies showed that: (a) iron accumulated in the sperm
   and other testes cells, and (b) spermatogenesis was markedly lower in
   the Fe1000 group. The concentration of alpha-tocopherol, ubiquinol-9,
   and ubiquinol-10 in the testes was inversely correlated with the
   extent of oxidation. Testes chemiluminescence was 45% higher in the
   Fe1000 group compared to controls (41 cps/cm(2)). Endogenous levels of
   lipid oxidation, evaluated as 2-thiobarbituric acid-reactive
   substances, were 46, 73, and 82% higher in the groups Fe250, Fe500,
   and Fe1000, respectively, than in controls (33.6 +/- 1.4 nmol/g
   tissue). Oxidative damage to DNA evaluated by the presence of
   8-oxo-2'-deoxyguanosine (oxo(8)dG), was 26, 39, and 74% higher in the
   Fe250, Fe500, and Fe1000 groups, respectively, than in the C group
   (2.3 +/- 0.1 oxo(8)dG/10(5)dG). Protein oxidation was measured as
   protein thiols and carbonyl content in proteins and glutamine synthase
   activity. Protein thiols content and glutamine synthase activity were
   similar in all the groups, while the protein-associated carbonyls
   content was 96% higher in the Fe1000 group than in the C group (2.1
   +/- 0.4 nmol/mg protein). No changes in the activities of superoxide
   dismutase, catalase, and glutathione peroxidase were observed. The
   results showed that in vivo iron overload induced oxidative stress and
   the impairment of spermatogenesis in rat testes that were dependent on
   the amount of iron supplemented and its accumulation in the tissue.
   Copyright 1999 Academic Press.
   
   PMID: 10562414, UI: 20031447
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