Increasing of Syncytial Knot and Fibrinoid Deposit in High-Cd Accumulated Human Placentas

Abstract

A toxic metal, cadmium (Cd), can accumulate in human organs. Placenta is usually used as indicator organ for Cd exposure. Therefore, we aim to investigate the different of placental morphology between the low- and high-Cd accumulated placentas. The samples were collected from 14 pregnant women who resided in low-Cd contaminated (L-Cd group) and high-Cd contaminated (HCd group) areas. The concentrations of Cd in blood (B-Cd), urine (U-Cd) and placentas (P-Cd) were measured by ICP-MS and AAS. The morphological appearance of placentas was examined by using routine paraffin section and H & E staining. The results showed that levels of B-Cd, U-Cd and P-Cd were significantly higher in H-Cd group than in L-Cd group (p= 0.001). Moreover, the B-Cd was positively correlated with U-Cd (rs= 0.823, p= 0.000) and P-Cd concentrations (rs= 0.854, p= 0.000). The appearances of syncytial knot (STK) and fibrinoid deposit (Fd) were obviously greater in H-Cd group than in L-Cd group (p= 0.007, p= 0.026). The STK was positively correlated with both Fd (rs= 0.572, p= 0.032) and P-Cd concentration (rs= 0.766, p= 0.001). Although the chorioamnitis and decidual inflammation features were found in both groups but the appearance in H-Cd group seems to be more severe than in L-Cd group. From these results, we suggested that high Cd level in placenta may be involved in morphological changes, especially STK and Fd increasing and probably disturb the connection between maternal and fetal circulation.