Evaluation of kidney injury biomarkers in rat amniotic fluid after gestational exposure to cadmium

Cadmium is a well-characterized nephrotoxic agent that is also capable of accumulating and diffusing across the placenta; however, only a few studies have addressed its effects over fetal kidneys and none of them has used a panel of sensitive and specific biomarkers for the detection of kidney injury. The goal of this study was to determine cadmium renal effects in rat fetuses by the quantification of early kidney injury biomarkers. Pregnant Wistar rats were exposed by inhalation to an isotonic saline solution or to CdCl2 solution (D-Del=1.48mg Cd kg(-1) day(-1)) during gestational days (GD) 8-20. On GD 21, dams were euthanized and samples obtained. Kidney injury biomarkers were quantified in amniotic fluid samples and fetal kidneys were microscopically evaluated to search for histological alterations. Our results showed that cadmium exposure significantly raised albumin, osteopontin, vascular endothelial growth factor and tissue inhibitor of metalloproteinases-1 levels in amniotic fluid, whereas it decreased creatinine. Clusterin, calbindin and IFN-inducible protein 10 did not show any change. Accordingly, histological findings showed tubular damage and precipitations in the renal pelvis. In conclusion, gestational exposure to cadmium induces structural alterations in fetal renal tissue that can be detected by some kidney injury biomarkers in amniotic fluid samples. Copyright (c) 2016 John Wiley & Sons, Ltd. Cadmium effects in fetal kidneys have not been widely studied, and no study has used early biomarkers for the detection of prenatal kidney injury. Pregnant Wistar rats were exposed to cadmium during gestation. Biomarkers of kidney injury were quantified in amniotic fluid (AF) samples, and fetal kidneys were processed for histological examination. Cadmium increased the levels of some biomarkers. Histological findings confirmed kidney alterations. In conclusion, kidney injury biomarkers in AF may be used to detect cadmium-induced fetal kidney damage.