Effect of maternal iron deficiency on placental gene expression on gestational day 18.5 in rats

Iron deficiency occurs when iron demands chronically exceed intake, and is particularly prevalent in pregnant women. Iron deficiency during pregnancy poses health risks for the baby. The placenta serves as the interface between a pregnant mother and her baby; thus, maternal iron deficiency may indirectly impact fetal growth and development by altering placental function. In this study, pregnant Sprague-Dawley rats were fed either a low-iron or iron-replete diet starting two weeks before mating. On gestational day 18.5, RNA was collected, and a Clariom S microarray was performed to elucidate differences in gene expression between gestaional day 18.5 placentas isolated from dams fed iron replete or iron deficient diets. Two weeks before mating, female rats were randomly assigned either to a control diet group (37 mg/kg iron) or an iron-restricted diet group (3 mg/kg iron diet). After 2 weeks, female rats were bred to age-matched males fed a standard rodent chow. Dams in the control group were maintained on the same control diet throughout pregnancy; dams on the iron-restricted diet were transferred to a diet that contained 10 mg/kg iron for the duration of the study. On GD18.5, placentas were isolated, RNA extracted using a TRIzol-RNeasy column hybrid protocol including on-column DNase I digestion, and purified. Each sample represents RNA pooled from 2 placentas from a single dam. Normalization and output file generation was performed with Affymetrix Gene Expression Console (Thermo) using the Robust Multi-Chip Analysis (RMA) algorithm [RMA-Gene-full].