HYPOXIA INDUCIBLE FACTOR 1α, bcl-2 PROTEIN AND SATELLITE INDICATORS OF INTRACELLULAR SIGNAL TRANSDUCTION PROCESSES IN HUMAN PLACENTA FROM INTRAUTERINE GROWTH RETARDED PREGNANCIES

Hypoxia inducible factor (HIF-1) is a heterodimeric transcriptional complex that plays pivotal role in the regulation of cellular utilization of oxygen as well as glucose and is an essential regulator of angiogenesis. In the present work we report a significant decrease in the levels of HIF-1α subunit as well as bcl-2 protein in human placenta from intrauterine growth retarded pregnancies. Respectively the amount of intracellular iron was decreased and 2-oxoglutarate concentration was significantly increased. Activity of poly-(ADP-ribose)-polymerase did not express any significant changes. Activity of apoptosis signal-regulating kinase 1 and internucleosomal DNA fragmentation were increased. Protein kinase C activity was decreased suggesting a cell growth deceleration. We assume the inhibition of cellular growth and stimulation of apoptotic cell death in human placenta upon intrauterine growth retardation.