Effects of Uranium Poisoning on Cultured Preimplantation Embryos

Abstract

The toxic effect of uranium in cultured preimplantation embryos of the mouse is presented. Embryos were obtained from hybrid females CBA x C57 BL following induction of superovulation and were incubated in M16 cultured medium. Two different experiments were performed. In one, embryos in a one-cell stage were placed in culture media with final concentrations of uranyl nitrate of 104 and 208 microg/mL during 120 h in the same dish. In the other experiment, embryos in a one-cell stage were placed in culture medium with uranyl nitrate with final U concentrations of 26, 52, 104, and 208 microg/mL. At 24 h, those embryos which had reached the two-cell stage were transferred to another culture dish to which fresh solutions with uranyl nitrate were added. The percentage of embryos in two-cell stage, morula, early blastocyst, expanded blastocyst, and hatched blastocyst were recorded at 24, 72, 96 and 120 h of culture. The results obtained showed that concentrations as from 26 microg U/mL induced the delay of embryo development and the impairment of blastomere proliferation. The toxic effect of uranium increased in those experiments in which the embryos were transferred to a new medium. This embryo-culture system appears to be appropriate to evaluate the toxic effect of uranium on embryos removed from maternal influences and represents a suitable test system for environmental pollutants.

Modes of action associated with uranium induced adverse effects in bone function and development

“…Uranium is also known to accumulate in areas of bone growth (Neuman et al, 1948;Rodrigues et al, 2013;Rowland and Farnham, 1969), where active calcification is occurring Durbin and Wrenn, 1975). Furthermore, ex-vivo studies using mouse preimplantation embryos (Kundt et al, 2000), and in vivo studies using the nonmammalian vertebrates Danio rerio and Xenopus laevis have shown that uranium exposure reduces embryo growth (Bourrachot et al, 2008;Mitchell et al, 2005). Taken together, the available studies provides evidence for a direct effect of uranium in developing animals.…”

A review of the effects of uranium and depleted uranium exposure on reproduction and fetal development

“…Intratesticular injection of enriched uranium compounds increased the incidence of cytogenic damage in developing mouse sperm (Hu and Zhu, 1990). In vitro studies showed that uranium is both cytotoxic and genotoxic to Chinese hamster ovary (CHO) cells (Lin et al, 1993) and reduces cell number in developing mouse embryos in culture (Kundt et al, 2000).…”

“…Lin et al (1993) indicated that uranium can produce decreased viability, depressed cell cycle kinetics, and an increase in several genotoxic endpoints in CHO cells. Uranium, delivered as uranyl nitrate, delayed development of mouse embryos in culture and was associated with lower embryo cell numbers through the hatched blastocyst stage, suggesting that uranium exposure resulted in severe alterations in DNA synthesis (Kundt et al, 2000). Several other metals arrest cell division under certain conditions, including chromium (VI) (Zhang et al, 2001), iron (Philpott et al, 1998), nickel (II) (Shiao et al, 1998), lithium (Mao et al, 2001), and beryllium (Lehnert et al, 2001).…”

Uranium in Drinking Water: Effects on Mouse Oocyte Quality

“…Studies of natural uranium compounds in rodents indicate that uranium is teratogenic and potentially toxic for the reproductive tissues (Domingo 2001;Arfsten et al 2001). There are a few studies available on male and female reproduction (Llobet et al 1991;Linares et al 2005;Arfsten et al 2005;Sanchez et al 2006) and in vivo or in vitro embryotoxicity (Domingo et al 1989;Kundt et al 2000); nevertheless, to our knowledge, there are no reports on oocytes with this contaminant at any dose.…”