Differential gene expression of somatotrophic and growth factors in response to in vivo hypoxia in human placenta.
OBJECTIVE
Hypoxia-inducible transcription factors (HIFs) have been characterized as the most important regulators of O(2)-dependent gene transcription. We investigated expression of HIF-dependent growth factors and HIF-independent somatotrophic factors in term placenta in response to hypoxic ischemia.


METHODS
Our cross-sectional in vivo analysis included term placentas of gestations complicated by the following: (1) birth asphyxia (n = 22); (2) chronic hypoxic ischemia (n = 22); and (3) controls (n = 28). Gene expression of leptin, insulin-like growth factor (IGF)-1, IGF-2, ghrelin, and human placental growth hormone (hPGH) were measured by TaqMan reverse transcriptase-polymerase chain reaction.


RESULTS
Acute and chronic hypoxia significantly increased leptin messenger ribonucleic acid (mRNA) levels, compared with controls (P < .001). Augmented IGF-2 mRNA levels were present in chronic hypoxia (P < .001) but not in birth asphyxia. IGF-1, ghrelin, and hPGH mRNA levels did not change in relation to hypoxia.


CONCLUSIONS
IGF-2 and leptin are suggested to be involved in adaptive response to hypoxic ischemia in term placenta with differential transcriptional regulation related to the duration of hypoxia.
Department of Pediatrics, Faculty of Medicine, Friedrich-Alexander University of Erlangen-Nürnberg, Erlangen, Germany. regina.trollmann@kinder.imed.uni-erlangen.de
Regina
R
Trollmann
Karin
K
Klingmüller
Ralf L
RL
Schild
Wolfgang
W
Rascher
Jörg
J
Dötsch
D003430:Cross-Sectional Studies; D015870:Gene Expression; D006801:Humans; D000860:Hypoxia / Q000209:etiology / Q000235:genetics*; D007231:Infant, Newborn; D007335:Insulin-Like Growth Factor II / Q000235:genetics; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics*; D007511:Ischemia / Q000150:complications / Q000235:genetics*; D020738:Leptin / Q000235:genetics; D010920:Placenta / Q000098:blood supply / Q000502:physiology*
D036341:Intercellular Signaling Peptides and Proteins; D020738:Leptin; D007335:Insulin-Like Growth Factor II