The Role Study Of Apoptosis In The Neural Tube Defects Genesis In Mouse

BACKGROUNDNeural tube defects (NTDs), such as spina bifida (SB) or exencephaly, are common congenital malformations leading to infant mortality or severe disability. The etiology of NTDs is multifactorial with a strong genetic component. we focus on the role of apoptosis genes in neurodevelopment.The present experiment aims to build NTDs mouse model induced by ATRA and study the effect of the interaction between apoptosis and apoptosis signaling on the development of NTDs.METTHODSHealthy adult C57BL/6J mice breed were selected and provided with a feed of 28mg/kg ATRA at E 8.0d, which induced the establishment of NTDs mouse model. The mouse embryos were taken at E11.5d, and examined the malformation of fetus by anatomical microscope. The mouse embryos were performed by preparation for paraffin series section using the staining of TdT-mediate x-dUTP Nick End Labeling (TUNEL).Image-pro plus software to take images by image analysis to calculate area (Area), optical density mean(MOD); control group and experimental groups, the data processing using statistical software SPSS13.0 univariate analysis of variance and t test, and its comprehensive analysis.RESULLTTS1. Excessive ATRA plays a significant role in embryo teratogenicity, which results uterus of pregnancy mice obviously hyperaemia and various NTDs (anencephalia and spina bifida).2. TUNEL method used can be found in E11.5d of tissure, apoptosis positive cells in NTDs mice was significantly higher that than the control groups, fluorescence intensity of the control groups. TUNEL positive signal is green fluorescence signal.CONCLUSION1.NTDs mouse model of C57BL/6J breed was successfully built induced by ATRA, which makes perfect model foundation for the study of pathogeny of NTDs.2. Apoptosis plays an important role in the morphogenesis and homeostasis of the developing central nervous system (CNS) by participating in folding, pinching off and fusion of neural walls. In these cases, excess apoptosis could result in insufficient numbers of cells to participate in the crucial morphogenetic movements underlying neural tube closure. BACKGROUNDNeural tube defects (NTDs), one of the most common birth defects in human, are multifactorial with complex genetic and environmental causes, although the genetic factors are almost completely unknown. The mutations on two genes involved in transcription, C386T of Msx2 gene and C1548 A of Slug gene are potential risk factors of NTDs.METTHODSThe study analyzed the genotypic distributions and allele frequencies of Msx2 C386T and Slug C1548A polymorphisms in DNA samples from 59 mothers with at least one previous child with NTDs (the NTD group) and 73 controls during the same period. Computer and analysis software were used to reconstruct the three-dimensional structures of the two mutation sites.RESULLTTSOur results indicated that there was a significant difference in the genotypes and allele frequencies of Msx2 C386T gene (TT 15.3%vs 4%, T 31.4%vs 11.6%, respectively) and Slug C1548A gene (AA 25.4%vs 5.5%, A 49.2%vs 21.6%, respectively) between NTD group and controls. Logistic regression analysis showed that, mutations on the two genes are potential risk factors of NTDs (P<0.05), the T allele Msx2 C386T odds ratio (OR) is 3.466 (95%CI 1.831-6.560) and the A allele Slug C1548A odds ratio (OR) is 3.444 (95%CI 2.021-5.868). X2 test analysis of Msx2 C386T and Slug C1548A showed that, mutations in both genes had a higher correlation coefficient in relationship with NTD than single gene mutation. Three-dimensional structure prediction revealed that Msx2 C386T results in threonine at the position of 129 of exon 2 changed into methionine, Slug C1548A results in aspartic acid on the position of 119 changed into glutamic acid, these mutations may lead to structural mutations or dysfunctions of proteins.CONCLUSIONThese results suggest that in Shanxi province Msx2 C386T and Slug C1548A gene polymorphisms may play a role in NTDs risk, whereas the impact of Msx2 C386T and Slug C1548A gene polymorphisms requires further clarification.