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Apoptosis in the Ovine Fetal Brain Following Placental Embolization and Intermittent Umbilical Cord Occlusion

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Abstract

The purpose of this study was to compare the regional distribution of apoptotic cells in the near term ovine fetal brain caused by prolonged moderate hypoxia, as seen in placental insufficiency, and intermittent severe hypoxia, as seen in umbilical cord compression, which may then contribute to adverse neurodevelopment in the postnatal life. We hypothesized that apoptosis in the fetal brain will be increased in response to both prolonged moderate hypoxia and intermittent severe hypoxia. Twenty-one near term (126-127 days) sheep were divided into 3 groups: control (CON; n = 7), placental embolization (EMB; n = 7), and umbilical cord occlusion (UCO; n = 8). The EMB group had microsphere injections into the umbilical arterial circulation until the oxygen content was at 50% of baseline value. The UCO group had complete cord occlusion for 2 minutes every hour, 6 times a day for 2 consecutive days. At 4 pm on day 2, the animals were euthanized; fetal brains were fixed and prepared for apoptosis staining using the terminal uridine deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay method. In the cerebellar white matter, there was a 3-fold increase in the number of TUNEL positive cells per 1000 cells in both EMB and UCO animals as compared to CON (P = .017). There was also a significant increase in the frontal cortical grey matter (layers 1-3) in EMB animals as compared to CON (P = .014). As such, apoptosis in the near term fetal sheep brain is altered with both sustained moderate hypoxia and intermittent severe hypoxia in the latter part of pregnancy, with potential for long-term neurological sequelae.

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References

  1. Blair E, Stanley FJ. Intrapartum asphyxia: a rare cause of cerebral palsy. J Pediatr. 1988;112(4):515–519.

    CAS  PubMed  Google Scholar 

  2. Nelson KB, Leviton A. How much of neonatal encephalopathy is due to birth asphyxia? Am J Dis Child. 1991;145(11):1325–1331.

    CAS  PubMed  Google Scholar 

  3. Ghidini A.Idiopathic fetal growth restriction: a pathophysiologic approach. Obstet Gynecol Surv. 1996;51(6):376–382.

    CAS  PubMed  Google Scholar 

  4. Gagnon R, Johnston L, Murotsuki J. Fetal placental embolization in the late-gestation ovine fetus: alterations in umbilical blood flow and fetal heart rate patterns. Am J Obstet Gynecol. 1996; 175(1):63–72.

    CAS  PubMed  Google Scholar 

  5. Nelson KB, Grether JK. Causes of cerebral palsy. Curr Opin Pediatr. 1999;11(6):487–491.

    CAS  PubMed  Google Scholar 

  6. de Haan M, Wyatt JS, Roth S, Vargha-Khadem F, Gadian D, Mishkin M. Brain and cognitive-behavioural development after asphyxia at term birth. Dev Sci. 2006;9(4):350–358.

    PubMed  Google Scholar 

  7. Lou HC. Etiology and pathogenesis of attention-deficit hyperactivity disorder (ADHD): significance of prematurity and perinatal hypoxic-haemodynamic encephalopathy. Acta Paediatr. 1996; 85(11):1266–1271.

    CAS  PubMed  Google Scholar 

  8. van Handel M, Swaab H, de Vries LS, Jongmans MJ. Long-term cognitive and behavioral consequences of neonatal encephalopathy following perinatal asphyxia: a review. Eur J Pediatr. 2007; 166(7):645–654.

    PubMed  PubMed Central  Google Scholar 

  9. Gagnon R, Johnston L, Murotsuki J. Fetal placental embolization in the late-gestation ovine fetus: alterations in umbilical blood flow and fetal heart rate patterns. Am J Obstet Gynecol. 1996; 175(1):63–72.

    CAS  PubMed  Google Scholar 

  10. Murotsuki J, Challis JR, Johnston L, Gagnon R. Increased fetal plasma prostaglandin E2 concentrations during fetal placental embolization in pregnant sheep. Am J Obstet Gynecol. 1995; 173(1):30–35.

    CAS  PubMed  Google Scholar 

  11. Mallard EC, Rees S, Stringer M, Cock ML, Harding R. Effects of chronic placental insufficiency on brain development in fetal sheep. Pediatr Res. 1998;43(2):262–270.

    CAS  PubMed  Google Scholar 

  12. McIntosh GH, Baghurst KI, Potter BJ, Hetzel BS. Foetal brain development in the sheep. Neuropathol Appl Neurobiol. 1979; 5(2):103–114.

    CAS  PubMed  Google Scholar 

  13. Duncan JR, Cock ML, Harding R, Rees SM. Neurotrophin expression in the hippocampus and cerebellum is affected by chronic placental insufficiency in the late gestational ovine fetus. Brain Res Dev Brain Res. 2004;153(2):243–250.

    CAS  PubMed  Google Scholar 

  14. Duncan JR, Cock ML, Harding R, Rees SM. Relation between damage to the placenta and the fetal brain after late-gestation placental embolization and fetal growth restriction in sheep. Am J Obstet Gynecol. 2000;183(4):1013–1022.

    CAS  PubMed  Google Scholar 

  15. Anyaegbunam A, Brustman L, Divon M, Langer O. The significance of antepartum variable decelerations. Am J Obstet Gynecol. 1986;155(4):707–710.

    CAS  PubMed  Google Scholar 

  16. Hoskins IA, Frieden FJ, Young BK. Variable decelerations in reactive nonstress tests with decreased amniotic fluid index predict fetal compromise. Am J Obstet Gynecol. 1991;165(4 pt 1):1094–1098.

    CAS  PubMed  Google Scholar 

  17. Osak R, Webster KM, Bocking AD, Campbell MK, Richardson BS. Nuchal cord evident at birth impacts on fetal size relative to that of the placenta. Early Hum Dev. 1997;49(3):193–202.

    CAS  PubMed  Google Scholar 

  18. Nelson KB, Grether JK. Potentially asphyxiating conditions and spastic cerebral palsy in infants of normal birth weight. Am J Obstet Gynecol. 1998;179(2):507–513.

    CAS  PubMed  Google Scholar 

  19. Clapp JF III, Lopez B, Simonean S. Nuchal cord and neurodevelopmental performance at 1 year. J Soc Gynecol Investig. 1999; 6(5):268–272.

    PubMed  Google Scholar 

  20. Falkowski A, Hammond R, Han V, Richardson B. Apoptosis in the preterm and near term ovine fetal brain and the effect of intermittent umbilical cord occlusion. Brain Res Dev Brain Res. 2002; 136(2):165–173.

    CAS  PubMed  Google Scholar 

  21. Mallard EC, Williams CE, Johnston BM, Gunning MI, Davis S, Gluckman PD. Repeated episodes of umbilical cord occlusion in fetal sheep lead to preferential damage to the striatum and sensitize the heart to further insults. Pediatr Res. 1995;37(6):707–713.

    CAS  PubMed  Google Scholar 

  22. Mallard EC, Williams CE, Johnston BM, Gluckman PD. Increased vulnerability to neuronal damage after umbilical cord occlusion in fetal sheep with advancing gestation. Am J Obstet Gynecol. 1994;170(1 pt 1):206–214.

    CAS  PubMed  Google Scholar 

  23. Mallard EC, Gunn AJ, Williams CE, Johnston BM, Gluckman PD. Transient umbilical cord occlusion causes hippocampal damage in the fetal sheep. Am J Obstet Gynecol. 1992;167(5):1423–1430.

    CAS  PubMed  Google Scholar 

  24. Edwards AD, Yue X, Cox P, et al. Apoptosis in the brains of infants suffering intrauterine cerebral injury. Pediatr Res. 1997; 42(5):684–689.

    CAS  PubMed  Google Scholar 

  25. Scott RJ, Hegyi L. Cell death in perinatal hypoxic-ischaemic brain injury. Neuropathol Appl Neurobiol. 1997;23(4):307–314.

    CAS  PubMed  Google Scholar 

  26. Yue X, Mehmet H, Penrice J, et al. Apoptosis and necrosis in the newborn piglet brain following transient cerebral hypoxia-ischaemia. Neuropathol Appl Neurobiol. 1997;23(1):16–25.

    CAS  PubMed  Google Scholar 

  27. Barone S Jr, Das KP, Lassiter TL, White LD. Vulnerable processes of nervous system development: a review of markers and methods. Neurotoxicology. 2000;21(1–2):15–36.

    CAS  PubMed  Google Scholar 

  28. Mallard C, Loeliger M, Copolov D, Rees S. Reduced number of neurons in the hippocampus and the cerebellum in the postnatal guinea-pig following intrauterine growth-restriction. Neuroscience. 2000;100(2):327–333.

    CAS  PubMed  Google Scholar 

  29. Ferrer I, Bernet E, Soriano E, del Rio T, Fonseca M. Naturally occurring cell death in the cerebral cortex of the rat and removal of dead cells by transitory phagocytes. Neuroscience. 1990;39(2): 451–458.

    CAS  PubMed  Google Scholar 

  30. Oppenheim RW. Cell death during development of the nervous system. Annu Rev Neurosci. 1991;14:453–501.

    CAS  PubMed  Google Scholar 

  31. Rakic S, Zecevic N. Programmed cell death in the developing human telencephalon. Eur J Neurosci. 2000;12(8):2721–2734.

    CAS  PubMed  Google Scholar 

  32. Hill IE, MacManus JP, Rasquinha I, Tuor UI. DNA fragmentation indicative of apoptosis following unilateral cerebral hypoxia-ischemia in the neonatal rat. Brain Res. 1995;676(2): 398–403.

    CAS  PubMed  Google Scholar 

  33. Beilharz EJ, Williams CE, Dragunow M, Sirimanne ES, Gluckman PD. Mechanisms of delayed cell death following hypoxicischemic injury in the immature rat: Evidence for apoptosis during selective neuronal loss. Brain Res Mol Brain Res. 1995;29(1):1–14.

    CAS  PubMed  Google Scholar 

  34. D’Amelio M, Cavallucci V, Cecconi F. Neuronal caspase-3 signaling: not only cell death. Cell Death Differ. 2010;17(7):1104–1114.

    PubMed  Google Scholar 

Download references

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Correspondence to Tuba Aksoy MD, MSc.

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Aksoy, T., Richardson, B.S., Han, V.K. et al. Apoptosis in the Ovine Fetal Brain Following Placental Embolization and Intermittent Umbilical Cord Occlusion. Reprod. Sci. 23, 249–256 (2016). https://doi.org/10.1177/1933719115602774

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