Turkish Neurosurgery
Effects of dexamethazone exposure on neural crest cells and primary and secondary neurulation during neurulation period in chick embryos
Serap Uslu2, Selin Tural Emon3, Nuray Alaca1, Duygu Çalık Kocatürk4, Ufuk Uslu5, Aysegül Uysal4
1Acıbadem Mehmet Ali Aydınlar University , Department of Physiotherapy and Rehabilitation, Istanbul,
2Istanbul Medeniyet University, Department of Histology and Embryology, İstanbul,
3Haydarpasa Numune Training and Research Hospital, Department of Neurosurgery, İstanbul,
4Ege University, Department of Histology and Embryology, İstanbul,
5Kartal Koşuyolu High Specialization Training , Department of Anesthesia and Reanimation, İstanbul,
DOI: 10.5137/1019-5149.JTN.34904-21.2
Aim:The aim of this study was to evaluate the effects of dexamethasone (Dex) treatment on neural crest cells and primary and secondary neurulation in chick embryosMaterial and Methods:Sixty fertilized eggs with an average weight of 65 ± 2 g were incubated in 60%–70% humidity at 37.2°C ± 0.1°C. After 26 h of incubation, the control group (n = 12) received 0.1 mg/kg saline (S), group 1 (n = 12) received 0.1 mg/kg Dex, group 2 (n = 12) received 1 mg/kg Dex, and group 3 (n = 12) received 5 mg/kg Dex into each embryonic disc. The eggs were incubated until Hamburger–Hamilton stage (HH) 15, HH18, and HH20. Then, the embryos were dissected and evaluated both macroscopically and microscopically.Results:The mortality rate in the control group, group 1, and groups 2 and 3 was 27%, 48%, and 100%, respectively. The neural tube thicknesses in group 1 significantly increased in HH15 and HH20 (p < 0.05). The mitosis number in group 1 significantly decreased in each stage (p < 0.05). Wnt-1 expression was significantly lower in group 1 in HH15 (p < 0.05) and HH18 (p < 0.05), but there was no significant difference in HH20 (p > 0.05). Fibroblast growth factor (FGF) expression was significantly lower in group 1 in HH15 (p < 0.05). The expression of N-cadherin was significantly higher in group 1 in HH20 (p < 0.05). Fibronectin expression decreased in group 1 in HH18 (p < 0.01).Conclusion:Although the Dex treatment did not result in a neural tube closure defect, the mortality rates and neural tube thicknesses increased, whereas mitotic activation and Wnt-1 and FGF signal pathways reduced in some stages.
Corresponding author : Nuray Alaca