Genotoxicity of organoselenium compounds in human leukocytes in vitro

Differential genotoxicity of diphenyl diselenide (PhSe)2and diphenyl ditelluride (PhTe)2

“…Recently, our research group demonstrated that organoselenium and organotellurium present hemolytic and genotoxic effects in human blood cells (Santos et al, 2009a; Santos et al, 2009b; Caeran Bueno et al, 2013), which is in accordance with results published by other laboratories in experimental bacteria and rodent models (Degrandi et al, 2010). Similarly, organoselenides and tellurides can be toxic in different in vivo and in vitro models of animal pathologies (Maciel et al, 2000; Taylor, 1996; Stangherlin, Rocha & Nogueira, 2009; Moretto et al, 2007; Heimfarth et al, 2011; Heimfarth et al, 2012a; Heimfarth et al, 2012b; Comparsi et al, 2012).…”

“…Mice blood leukocytes were isolated and used in the comet test but no pre-incubation was carried out (Santos et al, 2009a; Santos et al, 2009b; Meinerz et al, 2011). …”

“…This test has been used to investigate the effect of many toxic agents on DNA (Collins & Harrington, 2002; Blasiak, Arabski & Krupa, 2004). The comet assay was performed under alkaline conditions according to the procedures described by Santos et al (2009a) and Santos et al (2009b). The slides obtained from white blood cells of treated mice were analyzed under blind conditions by at least two individuals.…”

Selenium and Human Health: Witnessing a Copernican Revolution?

“…The ability to form selenide anion and generate superoxide via oxidation of GSH and other thiols was shown in vitro mainly for selenite, selenium dioxide, selenocystine and selenocystamine but not for elemental selenium, selenate, selenomethionine, selenoethionine and other not active compounds as shown by laboratory studies of Spallholz et al and others [112]. The ability to produce ROS explains dose dependent toxic effects of Se, observed in vitro and in vivo [108] and is considered to underlie its genotoxic [113,114] and proapoptotic activity [115][116][117]. However, some of these dose dependent effects, specifically DNA damage and apoptosis, were observed in vivo after treatment with SeMet, which is a Se compound regarded as nontoxic due to the inability to generate ROS [118][119][120].…”

Review of current and “omics” methods for assessing the toxicity (genotoxicity, teratogenicity and nephrotoxicity) of herbal medicines and mushrooms

“…In this well-established, highly sensitive, rapid, and simple genotoxicity test, isolated cells embedded in agarose are lysed, washed to remove membranes and proteins, briefly electrophoresed, stained and examined under epifluorescence microscopy; strand breaks, coming from either strand breakage or excision repair, result in DNA extending towards the anode in a structure resembling a "comet" (Singh et al, 1988;Speit et al, 2009;Berthelot-Ricou et al, 2011). Depending on experimental conditions, the migrating DNA (comet tail or derived parameters) reflects the amount of single-or double-strand breaks, alkalilabile sites, including incomplete excision repair sites, but also of DNA-DNA and DNA-protein cross-links (Duez et al, 2003;Speit and Henderson, 2005;Santos et al, 2009;Verschaeve et al, 2010). A broad spectrum of DNA damage can then be detected either by visual classification of comet morphologies ("visual scoring") (Ramos et al, 2001;Cavalcanti et al, 2010) or from morphological parameters obtained by image analysis and integration of intensity profiles using in-house or commercially available systems.…”