Maternal nutrient restriction upregulates growth signaling pathways in the cotyledonary artery of cow placentomes.
This study evaluated the role of MAPK/ERK1/2 and/or PI3-K/Akt signaling pathways in modulating bovine placentomal vascularity in response to maternal nutrient restriction. Beef cows were randomly assigned to control fed (Control, n=15, 100% of requirements) or nutrient restricted (NR, n=15, 50% requirements) diets from day 30 to day 125 of gestation. Ten cows from each dietary group were necropsied on day 125 (approximately 45% gestation), and the remaining cows in each diet group were then fed control diets and necropsied on day 250 (approximately 90% gestation). At day 125 of gestation, NR cows exhibited increased (P=0.06) COT vascularity, improved (P<0.05) placentome efficiency (fetal weight/placentomal weight), and increased (P<0.05) phosphorylated Akt and ERK1/2 in COT arteries compared to Control cows. By day 250, however, treatment differences in COT vascularity and phosphorylated Akt and ERK1/2 in COT arteries were lost. On both gestational days, no treatment difference was observed in the levels of phosphorylated Akt or ERK1/2 in CAR arteries. CAR vascularity was similar across treatment on day 125, but tended to be greater (P<0.10) in NR than Control cows on day 250. These data suggest that conceptuses react to an early gestational nutrient restriction by up-regulating COT growth signaling pathways associated with angiogenesis, and that these compensations do not persist to term.
Zhu
M J
MJ
Center for the Study of Fetal Programming, University of Wyoming, 1000 E. University Avenue, Laramie, WY 82071, USA.
Du
M
M
Hess
B W
BW
Means
W J
WJ
Nathanielsz
P W
PW
Ford
S P
SP
D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002417:Cattle; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D005260:Female; D020567:Fetal Weight; D005508:Food Deprivation / Q000502:physiology*; D005865:Gestational Age; D018919:Neovascularization, Physiologic / Q000502:physiology; D009929:Organ Size; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010766:Phosphorylation; D010920:Placenta / Q000098:blood supply*; D021041:Placental Circulation / Q000502:physiology*; D010929:Placentation; D011247:Pregnancy; D015398:Signal Transduction
D019869:Phosphatidylinositol 3-Kinases; D048049:Extracellular Signal-Regulated MAP Kinases