Article

Diphenyl diselenide supplementation delays the development of N-nitroso-N-methylurea-induced mammary tumors

Archive für Toxikologie (Impact Factor: 5.08). 09/2008; 82(9):655-663. DOI: 10.1007/s00204-007-0271-9

ABSTRACT The effect of dietary diphenyl diselenide (1ppm) on N-nitroso-N-methylurea (NMU)-induced mammary carcinogenesis was examined in female Wistar rats. Beginning at 5weeks of age, the animals
were fed with either control or diphenyl-diselenide-supplied diets until the end of the study (210days). At 50days of age,
mammary tumor was induced by the administration of three doses of NMU (50mg/kg body wt, intraperitoneally) once a week for
3weeks. In experimental trials, latency to tumor onset was extended in rats fed with diet supplemented with diphenyl diselenide
(P<0.05). The incidence and frequency of tumors were significantly small in animals supplemented with diphenyl diselenide.
However, the multiplicity of tumors was not altered by dietary diphenyl diselenide. Diphenyl diselenide supplementation also
restored superoxide dismutase (SOD) activity and vitamin C levels altered in the NMU group (P<0.05). Our results suggest that diphenyl diselenide can be considered a chemopreventive agent, even when supplemented at
a relatively low concentration.

Download full-text

Full-text

Available from: Cristina W Nogueira, May 30, 2014
0 Followers
 · 
132 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Hypothyroidism has been associated to psychiatric disorders development and tissue oxidative damage. In this study, we evaluated the effect of diphenyl diselenide supplementation on depressive-like behavior triggered by methimazole exposure in female rats. Additionally, thiobarbituric acid reactive substances (TBARS), reactive oxygen species (ROS) and non-protein (NP-SH) thiols levels were analyzed in cerebral cortex, hippocampus and striatum structures. Monoamino oxidase (MAO) activity was evaluated in total brain. Firstly, female rats received methimazole (MTZ) 20mg/100ml in the drinking water for 30days and were evaluated in open-field and forced swimming tests (FST). In this set of experiments, the rats exposed to MTZ presented a depressive-like behavior, which was evidenced by a significant increase in the immobility time when compared to control group. Thereafter, MTZ-induced hypothyroid rats received either a standard or a diet containing 5ppm of diphenyl diselenide, and then they were evaluated monthly in open-field and FST tests during 3months. No alteration on the locomotor performance was observed among the groups. The depressive-like behavior of hypothyroid rats was blunted by diphenyl diselenide supplementation during all experimental periods. The levels of thyroid hormones remained low in MTZ exposed groups until the end of experimental period. MTZ group had an increase in TBARS and ROS levels that were restored by diphenyl diselenide supplementation. NP-SH content of cerebral structures was not modified by MTZ exposure and/or diphenyl diselenide supplementation. Diphenyl diselenide supplementation restored the MAO B activity that was decreased in MTZ group. In summary, our results show that hypothyroidism induced by methimazole triggers a depressive-like behavior in female rats and that dietary diphenyl diselenide was able in reducing this effect.
    Physiology & Behavior 11/2013; 124. DOI:10.1016/j.physbeh.2013.10.036 · 3.03 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Several diets employed in aquaculture are enriched with selenium (Se), as it is a fundamental element to aquatic vertebrates. Diphenyl diselenide [(PhSe)2], which is a synthetic organoselenium compound, has been considered a potential antioxidant agent in different experimental models. Thus, the aim of this study was to evaluate the effects of dietary diphenyl diselenide at concentrations of 1.5, 3.0, and 5.0 mg/kg for 60 days and to determine its optimal supplemental level for carp, Cyprinus carpio. Neither growth retardation nor hepatoxicity was induced by the inclusion of diphenyl diselenide at concentrations ranging from 1.5 to 5.0 mg/kg. In addition, the inclusion of 3.0 mg/kg of diphenyl diselenide stimulated the weight and length of the carp. The supplementation with 1.5 and 3.0 mg/kg of diphenyl diselenide did not produce oxidative damage in the tissues, verified by peroxidation lipid and protein carbonyl assays. However, at 5.0 mg/kg, it caused an increase of the lipid peroxidation in the liver, brain, and muscle, and inhibited the cerebral acetylcholinesterase activity. An increase of the hepatic superoxide dismutase activity and non-protein thiols content in all tissues and ascorbic acid in the liver, gills, and brain was verified in carp fed with the diet containing 3.0 mg/kg of diphenyl diselenide. This diet had advantageous effects for the fish used in experiments. Therefore, this compound could be considered a beneficial dietary supplement for carp nutrition.
    Fish Physiology and Biochemistry 07/2013; DOI:10.1007/s10695-013-9831-5 · 1.68 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Cognitive deficits have been observed in different animal models of adult-onset hypothyroidism. Thus, this study was delineated to evaluate whether diphenyl diselenide, an organoselenium compound with neuroprotective and antioxidant properties, could afford protection against the detrimental effects of hypothyroidism on behavioral parameters. Hypothyroidism condition was induced in female rats by continuous exposure to methimazole (MTZ) at 20 mg/100 ml in the drinking water, during 3 months. MTZ-induced hypothyroid rats were fed with either standard or a diet containing 5 ppm of diphenyl diselenide for 3 months. Behavioral assessments were performed monthly, in the following order: elevated plus maze, open field and Morris water maze. The levels of thyroid hormones in the animals exposed to MTZ were lower than control until the end of experimental period. The rats exposed to MTZ had a significant weight loss from the first month, which was not modified by diphenyl diselenide supplementation. In elevated plus maze test, MTZ exposure caused a reduction on the number of entries of animals in closed arms, which was avoided by diphenyl diselenide supplementation. In Morris water maze, the parameters latency to reach the platform and distance performed to find the escape platform in the test session were significantly greater in MTZ group when compared to control. These cognitive deficits observed in MTZ-induced hypothyroid rats were restored by dietary diphenyl diselenide. The group fed with diphenyl diselenide alone exhibited a better spatial learning and memory capability in some parameters of Morris water maze when compared to the control group. In summary, our data provide evidence of the effectiveness of dietary diphenyl diselenide in improving the performance of control and hypothyroid rats in the water maze test.
    International journal of developmental neuroscience: the official journal of the International Society for Developmental Neuroscience 04/2012; 30(2):83-9. DOI:10.1016/j.ijdevneu.2011.12.011 · 2.92 Impact Factor