title: Downregulation of placental S100P is associated with cadmium exposure in Guiyu, an e-waste recycling town in China.
abstract: Excessive release of heavy metals, especially cadmium (Cd) and lead (Pb), results from primitive electronic waste (e-waste) recycling activities in Guiyu, China, and has adverse effects on the health of local infants and pregnant women. We investigated the expression of placental S100P, a Ca(2+)-binding protein, as a biological indicator of heavy-metal environmental pollution in pregnant women involved in these activities and constantly exposed to Cd and Pb. We included 105 pregnant women in the study: 55 from Guiyu and 50 from Shantou, an area not involved in e-waste recycling. The placental concentrations of Cd and Pb (PCCd, PCPb) after birth were measured by graphite-furnace atomic-absorption spectrometry. S100P mRNA expression was determined by semi-quantitative RT-PCR and real-time quantitative PCR. S100P protein expression was examined by western blot analysis and immunohistochemistry. The expression of metallothionein (MT), previously found upregulated after heavy metal contamination, was used for comparison. Placentas from Guiyu women showed 62.8% higher Cd concentrations, higher MT levels, and lower S100P protein levels than placentas from Shantou women. Furthermore, PCCd was negatively correlated with S100P protein expression and positively with MT expression, with no correlation between PCPb and S100P or MT expression. The PCCd-associated downregulation of S100P in placentas from Guiyu women suggests that S100P might be an effective biological indicator in the placental response to Cd toxicity in areas of e-waste recycling.
authors: Department of Preventive Medicine, Shantou University Medical College, Shantou, Guangdong 515041, China.
authors: Qingying
authors: Q
authors: Zhang
authors: Taimei
authors: T
authors: Zhou
authors: Xijin
authors: X
authors: Xu
authors: Yongyong
authors: Y
authors: Guo
authors: Zhiguo
authors: Z
authors: Zhao
authors: Min
authors: M
authors: Zhu
authors: Weiqiu
authors: W
authors: Li
authors: Deqing
authors: D
authors: Yi
authors: Xia
authors: X
authors: Huo
mesh_terms: D000328:Adult; D015153:Blotting, Western; D002104:Cadmium / Q000032:analysis / Q000378:metabolism*; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D002681:China; D015536:Down-Regulation; D059029:Electronic Waste; D004781:Environmental Exposure; D004785:Environmental Pollutants / Q000032:analysis / Q000378:metabolism*; D005260:Female; D006801:Humans; D007854:Lead / Q000032:analysis / Q000378:metabolism*; D008297:Male; D008668:Metallothionein / Q000378:metabolism; D009363:Neoplasm Proteins / Q000378:metabolism*; D010920:Placenta / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D012333:RNA, Messenger / Q000235:genetics; D059027:Recycling; D013054:Spectrophotometry, Atomic; D055815:Young Adult
chemical_list: D002135:Calcium-Binding Proteins; D004785:Environmental Pollutants; D009363:Neoplasm Proteins; D012333:RNA, Messenger; C103003:S100P protein, human; D002104:Cadmium; D007854:Lead; D008668:Metallothionein