Metals in human placenta: focus on the effects of cadmium on steroid hormones and leptin.
Cadmium and other metallic ions can act as metalloestrogens and endocrine disruptors of reproductive tissues and fetal development in mammals, including humans. The detrimental effects occur with respect to the synthesis of both steroid and polypeptide hormones in the placenta. Leptin is produced by the trophoblast and may regulate fetal organogenesis and development. In human term placentas, concentrations of toxic metals and their effects on steroidogenesis were assessed in healthy parturients (109 non-smokers and 99 smokers) in relation to tobacco smoking. Trace elements (cadmium, lead, iron, zinc and copper) were analyzed in placentas using atomic absorption spectroscopy, and steroid hormones (progesterone and estradiol) were assayed in placental samples by an enzyme-immunometric method. Cadmium concentrations were doubled in placentas of smokers as compared with non-smokers, and placental lead and zinc concentrations increased significantly. Placental concentrations of iron, copper, progesterone and estradiol did not differ. In addition, human trophoblast cells were co-cultured with 0, 5, 10 or 20 microm CdCl(2) for 96 h and leptin mRNA assessed by quantitative polymerase chain reaction. Leptin mRNA declined dose-responsively as a result of CdCl(2) exposure. Collectively, the results confirm that human placental tissue offers a unique opportunity to biomonitor cadmium exposure in both the maternal and the internal fetal environments. In addition, the results strongly suggest that cadmium may cause a decline in placental leptin synthesis, as we have previously shown for placental progesterone production. This may constitute further evidence of the endocrine-disrupting effects of cadmium, as a constituent of tobacco smoke, on reproduction in women.
Clinical Hospital Merkur, Zagreb, Croatia.
Sandra
S
Stasenko
Elease M
EM
Bradford
Martina
M
Piasek
Michael C
MC
Henson
Veda M
VM
Varnai
Jasna
J
Jurasović
Vesna
V
Kusec
D000328:Adult; D049628:Body Size / Q000502:physiology; D002104:Cadmium / Q000032:analysis* / Q000633:toxicity*; D019256:Cadmium Chloride / Q000494:pharmacology; D002478:Cells, Cultured; D052244:Endocrine Disruptors / Q000032:analysis* / Q000633:toxicity*; D004784:Environmental Monitoring / Q000379:methods; D004958:Estradiol / Q000378:metabolism; D005260:Female; D012739:Gonadal Steroid Hormones / Q000032:analysis*; D006801:Humans; D007231:Infant, Newborn; D020738:Leptin / Q000235:genetics / Q000378:metabolism; D008297:Male; D018811:Maternal Exposure; D019216:Metals, Heavy / Q000032:analysis / Q000633:toxicity; D010920:Placenta / Q000737:chemistry* / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D011247:Pregnancy; D011374:Progesterone / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D012907:Smoking / Q000378:metabolism / Q000503:physiopathology; D011795:Surveys and Questionnaires; D014327:Trophoblasts / Q000378:metabolism; D055815:Young Adult
D052244:Endocrine Disruptors; D012739:Gonadal Steroid Hormones; D020738:Leptin; D019216:Metals, Heavy; D012333:RNA, Messenger; D002104:Cadmium; D011374:Progesterone; D004958:Estradiol; D019256:Cadmium Chloride