PERINATAL HYPOCUPROSIS AFFECTS SYNTHESIS AND COMPOSITION OF NEONATAL LUNG COLLAGEN, ELASTIN, AND SURFACTANT

To investigate the role of iron, ascorbate, and fructose on copper dep letion and the effect of copper depletion on neonatal lung collagen, e lastin, and surfactant, female rabbits were fed a control diet [10 par ts per million (ppm) copper], a basal marginal copper diet (1.5 ppm), or a basal diet containing a high concentration of iron (1,750 ppm), a scorbic acid (1%, wt/wt), or fructose (20% of carbohydrates, wt/wt) or a combination of iron, ascorbic acid, and fructose throughout gestati on. Whereas 10% of neonates in the control group died in the first 24 h, 27-67% of the offspring of rabbits fed the marginal copper diet die d. Birth weight was also lower for the pups of the females fed the mar ginal copper diets. Lungs of neonates born to females fed iron or asco rbate and marginal copper diets had low levels of copper, high proport ions of acid-extractable, high-molecular-weight collagen, and low lysy l-oxidase activities, consistent with incomplete maturation of collage n. The bronchoalveolar lavage fluids of newborns whose mothers were fe d marginal copper diets alone or in combination with iron and/or ascor bate had lower levels of total surfactant phospholipids than the fluid s from lungs of control newborns. The lower surfactant phospholipid co ntent of these groups could be attributed mainly to lower phosphatidyl choline and, in particular, dipalmitoylphosphatidylcholine levels. The se results suggest that high maternal intakes of iron, ascorbate, or t heir combination in pregnancy deplete biologically available copper, w hich in turn induces neonatal lung abnormalities.