Fetal growth restriction has long-term effects on postnatal lung structure in sheep.
We have previously shown that fetal growth restriction (FGR) during late gestation in sheep affects lung development in the near-term fetus and at 8 wk after birth. In the present study, our aim was to determine the effects of FGR on the structure of the lungs at 2 y after birth; our hypothesis was that changes observed at 8 wk after birth would persist until maturity. FGR was induced in sheep by umbilicoplacental embolization, which was maintained from 120 d until delivery at term (approximately 147 d); birth weights of FGR lambs were 41% lower than in controls. At 2 y after birth, body and lung weights were not different, but there were 28% fewer alveoli and alveoli were significantly larger than in controls; hence there was a 10% reduction in the internal surface area relative to lung volume in FGR sheep compared with controls. The lungs of FGR sheep, compared with controls, had thicker interalveolar septa as a result of increased extracellular matrix deposition; the alveolar blood-air barrier was also thicker, largely because of an 82% increase in basement membrane thickness. These changes are qualitatively similar to those observed at 8 wk. Our data show that structural alterations in the lungs induced by FGR that were apparent at 8 wk were still evident at 2 y after birth, indicating that FGR may result in permanent changes in the structure of the lungs of the offspring and may affect respiratory health and lung aging later in life.
Maritz
Gert S
GS
Department of Physiology, University of the West Cape, Bellville, South Africa.
Cock
Megan L
ML
Louey
Samantha
S
Suzuki
Keiji
K
Harding
Richard
R
D000367:Age Factors; D000818:Animals; D004247:DNA / Q000378:metabolism; D004549:Elastin / Q000378:metabolism; D005260:Female; D005317:Fetal Growth Retardation / Q000473:pathology* / Q000503:physiopathology*; D008176:Lung Volume Measurements; D008854:Microscopy, Electron; D009929:Organ Size; D010100:Oxygen / Q000097:blood; D011247:Pregnancy; D011506:Proteins / Q000378:metabolism; D011650:Pulmonary Alveoli / Q000196:embryology / Q000254:growth & development* / Q000473:pathology*; D011659:Pulmonary Gas Exchange; D020545:Respiratory Mucosa / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D012756:Sheep
D011506:Proteins; D004247:DNA; D004549:Elastin; D010100:Oxygen