Ethanol Decreases Zinc Transfer to the Fetus in Normal but Not Metallothionein‐Null Mice

Abstract

The results show (a) that ethanol interferes with the transfer of Zn to the fetus, and that this is MT dependent, and (b) that the increase in plasma Zn seen in MT-/- mice after ethanol administration is a result of Zn release from the skin and muscle, in the absence of hepatic Zn sequestration.

Zinc Supplementation at the Time of Ethanol Exposure Ameliorates Teratogenicity in Mice

“…Furthermore, we demonstrated that, contrary to what occurs in MTϩ/ϩ mice, plasma Zn concentrations in MTϪ/Ϫ mice increase substantially (by up to 50%) after ethanol treatment. This was later shown to be a consequence of Zn release from skin and muscle (Carey et al, 2000b). These experiments, where ethanol is administered acutely to mice, are comparable to the human setting where pregnant women consume alcoholic beverages in a binge-type manner.…”

Metallothionein: the multipurpose protein

“…4). It is well established that maternal hepatic MT induction results in an accumulation of Zn within the liver to the detriment of plasma Zn concentration (see [220] and arsenic are known inducers of MT, and have been shown to impair the transfer of Zn from mother to fetus when administered during the organogenic period [223][224][225][226][227][228]. Furthermore, the types of fetal abnormalities resulting from these teratogenic insults are very similar to those caused by Zn deficiency itself, thus implying, at least to some extent, a common underlying etiology [220].…”

Dietary Zinc Supplementation Throughout Pregnancy Protects Against Fetal Dysmorphology and Improves Postnatal Survival After Prenatal Ethanol Exposure in Mice

“…This caused an increase in liver Zn concentration, a concomitant decrease in maternal plasma Zn, and a reduction in embryonic Zn accrual (Taubeneck et al., 1994). Marked reductions in the transfer of 65 Zn to the fetus and in total fetal Zn content have been demonstrated after prenatal ethanol exposure in mice and rats (Carey et al., 2000a; Ghishan et al., 1982; Taubeneck et al., 1994). Our group using a MT‐knockout mouse have since demonstrated the importance of MT in fetal dysmorphology caused by ethanol exposure during organogenesis.…”