Zinc insufficiency mediates ethanol-induced alveolar macrophage dysfunction in the pregnant female mouse

Abstract

AIMS: (a) Establish the minimum number of weeks of chronic ethanol ingestion needed to perturb zinc homeostasis, (b) Examine intracellular zinc status in the alveolar macrophages (AMs) when ethanol ingestion is combined with pregnancy, (c) Investigate whether in vitro zinc treatment reverses the effects of ethanol ingestion on the AM. METHODS: C57BL/6 female mice were fed a liquid diet (±25% ethanol-derived calories) during preconception and pregnancy. The control group was pair-fed to the ethanol group. In the isolated AMs, we measured intracellular AM zinc levels, zinc transporter expression, alternative activation and phagocytic index. Zinc acetate was added to some cells prior to analysis. RESULTS: Intracellular zinc levels in the AM decreased within 3 weeks of ethanol ingestion. After ethanol ingestion prior to and during pregnancy, zinc transporter expression and intracellular zinc levels were decreased in the AMs when compared with controls. Bacterial clearance was decreased because the AMs were alternatively activated. In vitro additions of zinc reversed these effects of ethanol. CONCLUSION: Ethanol ingestion prior to and during pregnancy perturbed AM zinc balance resulting in impaired bacterial clearance, but these effects were ameliorated by in vitro zinc treatments.