US EPA

4979209 

Journal Article 

Human placenta and embryonic nutrition: importance of environmental and social factors 

Miller, RK; D'Gregorio, RP; Faber, W; Asai, M; Eisenmann, C; Breen, J; Czekierdowski, A; Jessee, L 

1994 

Yes 

Developmental Brain Dysfunction
ISSN: 1019-5815 

7 

English 

The placenta is well known as the conduit for the transfer of the nutrients (amino acids and carbohydrates) for normal development as well as for the elimination of the waste products. Yet the placenta is also the modulator of the pregnancy, e.g. controlling maternal physiology from being a carbohydrate user to being a fatty acid consumer via human placental lactogen. As part of the modulator role, the human placenta can also be the site for biotransformation of nutrients and drugs to more toxic forms. For years, the study of in utero nutrition and the placenta has concentrated upon small molecules, e.g., amino acids and glucose, to the exclusion of vitamins and in some cases minerals. The transfer and metabolism mechanisms for vitamin A (retinoids) and vitamin B12 (cyanocobalamin) will be examined under in vitro human placental perfusion conditions. Further studies will investigate environmental exposures to metals, e.g. methyl mercury and cadmium, and the importance of dietary and personal habit (smoking) modification to limit exposure to the conceptus utilizing biomarkers of exposure (metal content in blood, tissue and hair) as well as biomarkers of effect (induction of metallothionein). Thus, this presentation will examine the critical role the placenta does play in embryonic nutrition as well as being a site for toxic action.