Hypoxia regulates the expression of fatty acid-binding proteins in primary term human trophoblasts.
OBJECTIVE
Fatty acids (FAs) are essential for fetal development. Cellular FA uptake is modulated by fatty acid-binding proteins (FABPs). We hypothesized that hypoxia regulates the expression of FABPs in human trophoblasts.


METHODS
Primary term human trophoblasts were cultured for 72 hours in either standard (O2 = 20%) or hypoxic (O2 < 1%) conditions. FABP expression was interrogated using polymerase chain reaction and Western immunoblotting. Trophoblast lipid droplets were examined using dipyrromethene boron difluoride 493/503 staining.


RESULTS
We detected the expression of FABP1, -3, -4, -5, and pm but not FABP2 or FABP6-9 subtypes in trophoblasts. Exposure to hypoxia markedly increased lipid droplet accumulation in trophoblasts. Consistent with this observation, hypoxia enhanced the expression of FABP1, -3, and -4. Lastly, agonists of peroxisome proliferator-activated receptor-gamma enhanced the expression of FABP1 and -4 in trophoblasts.


CONCLUSIONS
Hypoxia enhances the expression of FABP1, -3, and -4 in term human trophoblasts, suggesting that FABPs support fat accumulation in the hypoxic placenta.
Biron-Shental
Tal
T
Department of Obstetrics and Gynecology, Washington University in St Louis School of Medicine, St Louis, MO, USA.
Schaiff
W Timothy
WT
Ratajczak
Christine K
CK
Bildirici
Ibrahim
I
Nelson
D Michael
DM
Sadovsky
Yoel
Y
D015153:Blotting, Western; D002478:Cells, Cultured; D017931:DNA Primers; D000074026:Fatty Acid Binding Protein 3; D050556:Fatty Acid-Binding Proteins / Q000378:metabolism*; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology*; D047468:Immunoprecipitation; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014327:Trophoblasts / Q000378:metabolism*