Effect on the offspring of pregnant females CD-1 mice treated with a single thallium(I) application.

Thallium (Tl) is a highly toxic metal for human beings; higher amounts found in diverse fluids of pregnant women are associated with low birth weight and preterm birth. However, experimental data concerning their effects on the embryonic development of mammalian organisms are limited. Hence, in the present work, TI(I) acetate of 0, 4.6, 9.2, or 18.5 mg/kg body weight were administered by intraperitoneal injection to groups of 10 pregnant CD-1 mice on the 7th gestational day, and animals were sacrificed on day 18 of gestation. The fetuses obtained showed some variations, such as trunk bent over (18.5 mg/kg), tail variations (all doses), forelimbs malrotation and hind limbs (all doses). Skeletal examination of the fetuses showed a delay in the ossification of skull bones, ribs, and limbs (all doses). In conclusion, the Intraperitoneal injection of Tl(I) acetate to pregnant mice induced morphological variations and a delay of the fetus ossification.

Genotoxicity of Casiopeina III-Ea in mouse bone marrow cells.

Casiopeina III-Ea® (Cas III-Ea®) is a chelated copper complex with antineoplastic activity that is capable of reducing tumor size and inducing antiproliferative and apoptotic effects. However, little is known about its in vivo genotoxic effects. Therefore, this study evaluated two cytogenetic and two proliferative parameters 24 h after the administration of Casiopeina III-Ea® to male CD-1 mice. Three doses of Cas III-Ea® were administered by intraperitoneal injections of 1.69, 3.39 and 6.76 mg/kg (corresponding to 1/8, 1/4 and 1/2 of LD50, respectively). A reduction in the mitotic index (MI) and an increased numbers of cells with structural chromosomal aberrations (SCA) were detected. Additionally, a low but significant increase in the frequency of sister chromatid exchange (SCE) was observed at the highest dose. Changes in the DNA replication index (RI) were not observed. These results indicate that Casiopeina III-Ea® shows cytotoxic and clastogenic activity in bone marrow cells from treated mice.

Evaluation of cytogenetic and DNA damage caused by thallium(I) acetate in human blood cells.

Although thallium is detrimental to all living organisms, information regarding the mutagenic and genotoxic effects of this element and its compounds remains scarce. Therefore, we tested the genotoxic and cytotoxic effects of thallium(I) acetate on human peripheral blood cells in vitro using structural chromosomal aberrations (SCAs), sister chromatid exchanges (SCEs), and single-cell gel electrophoresis (at pH >13 or 12.1) analysis. Whole blood samples were incubated with 0.5, 1, 5, 10, 50, or 100 µg/mL thallium salt. Exposure to this metal compound resulted in a clear dose-dependent reduction in the mitotic and replicative indices. An increase in SCAs was evident in the treated group compared with the control group, and significant differences were observed in the percentage of cells with SCAs when metaphase cells were treated with 0.5-10 µg/mL of thallium(I). The SCE test did not reveal any significant differences. We observed that a 1-h treatment with thallium(I) at pH > 13 significantly increased the comet length for all the concentrations tested; however, at pH 12.1, only the two highest concentrations affected the comet length. These results suggested that thallium(I) acetate induces cytotoxic, cytostatic, and clastogenic effects, as well as DNA damage.

DNA damage induction in human cells exposed to vanadium oxides in vitro.

Vanadium and vanadium salts cause genotoxicity and elicit variable biological effects depending on several factors. In the present study, we analyzed and compared the DNA damage and repair processes induced by vanadium in three oxidation states. We used human blood leukocytes in vitro and in a single cell gel electrophoresis assay at two pH values. We observed that vanadium(III) trioxide and vanadium(V) pentoxide produced DNA single-strand breaks at all of the concentrations (1, 2, 4, or 8 µg/ml) and treatment times (2, 4, or 6 h) tested. Vanadium(IV) tetraoxide treatment significantly increased DNA damage at all concentrations for 4 or 6 h of treatment but not for 2 h of treatment. The DNA repair kinetics indicated that most of the cells exposed to vanadium III and V for 4 h recovered within the repair incubation time of 90 min; however, those exposed to vanadium(IV) repaired their DNA within 120 min. The data at pH 9 indicated that vanadium(IV) tetraoxide induced DNA double-strand breaks. Our results show that the genotoxic effect of vanadium can be produced by any of its three oxidation states. However, vanadium(IV) induces double-strand breaks, and it is known that these lesions are linked with forming structural chromosomal aberrations.

Age-related sex differences in glutathione peroxidase and oxidative DNA damage in a healthy Mexican population.

BACKGROUND AND OBJECTIVE: It has been proposed that women have an estrogen activity-linked biological antioxidant advantage and that this advantage is lost in the postmenopausal stage. The latter remains controversial. Our aim was to determine age-related sex differences in oxidative stress and oxidative DNA damage in a healthy Mexican population. METHODS: A cross-sectional and comparative study was carried out in a convenience sample of 162 healthy subjects aged as follows: (1) 25-44 years (n = 35 women and 38 men), (2) 45-64 years (n = 41 women and 27 men), and (3) >or=65 years (n = 13 women and 8 men). We measured plasma lipoperoxides (LPO), superoxide dismutase (SOD), glutathione peroxidase (GPx), and DNA damage by comet assay. RESULTS: We found greater activity of GPx in women than in men according to age increase (p < 0.05). This activity is maintained in old age in women. In contrast, men exhibited a significant diminution in GPx according to age increase. Similarly, we observed a greater percentage of cells without oxidative DNA damage in women in the 45-64-years age group and in the group of women aged >or=65 years. CONCLUSIONS: Our findings suggest that women have a more efficient antioxidant activity than men, which has been linked with the greater longevity observed in women.

Chromosomal damage induced by vanadium oxides in human peripheral lymphocytes.

Fly ash, the inorganic residue resulting from the combustion of some fuels, may almost exclusively contain vanadium oxides, compounds which exert potential toxic effects on a wide variety of in vitro and in vivo biological systems. Because information related to the oxidation state responsible for inducing genotoxic effects is controversial, the aim of the present study was to evaluate the effects of three vanadium salts in vitro. Human peripheral lymphocyte cultures were exposed to 1, 2, 4, or 8 microg/mL of vanadium(III) trioxide, vanadium(IV) tetraoxide, or vanadium(V) pentoxide (V(2)O(3), V(2)O(4), or V(2)O(5), respectively). These cultures were then screened for structural chromosomal aberrations, and mitotic index (MI) measurements were made. Cytogenetic evaluations showed that only V(2)O(4) increased the percentage of aberrant cells (without gaps) and chromosome damage (including and excluding gaps), while all compounds led to a decrease in the MI. These results demonstrate that vanadium(III), vanadium(IV), and vanadium(V) are all capable of inducing cytotoxicity, but only oxidation state IV induces clastogenic effects.