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.
Trollmann
Regina
R
Department of Pediatrics, Faculty of Medicine, Friedrich-Alexander University of Erlangen-Nürnberg, Erlangen, Germany. regina.trollmann@kinder.imed.uni-erlangen.de
Klingmüller
Karin
K
Schild
Ralf L
RL
Rascher
Wolfgang
W
Dötsch
Jörg
J
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