Antenatal taurine supplementation improves neural axon development in fetal rats with intrauterine growth restriction by inhibiting the activity of Rho-ROCK signaling pathway
10.3760/cma.j.issn.1007-9408.2017.01.009
- VernacularTitle:孕鼠补充牛磺酸抑制生长受限胎鼠脑组织Rho-ROCK信号通路活性促进神经轴突发育
- Author:
Zulin LU
;
Jing LIU
;
Fang LI
;
Xiangwen LI
;
Yan WANG
- Keywords:
Fetal growth retardation;
Taurine;
Rho-associated kinases;
Synaptophysin;
Signal transduction;
Axons;
Rats,Sprague-Dawley
- From:
Chinese Journal of Perinatal Medicine
2017;20(1):38-44
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo investigate the effects of prenatal taurine supplementation on the Rho-ROCK signaling pathway activity and synaptophysin (Syp) expression in brain tissues of rats with intrauterine growth restriction.MethodsEighteen pregnant Sprague-Dawley rats were randomly divided into control group, fetal growth restriction (FGR) group and taurine group, with six rats in each group. Low-protein diet was given in FGR and taurine groups to establish an FGR model. Taurine 300 mg/(kg·d) was supplemented from gestational day 12 until delivery in taurine group. The mRNA expression levels of neurite growth inhibitor-A(Nogo-A), neurite growth inhibitor receptor (NgR), Rho-A and ROCKⅡin fetal rat brain were detected using reverse transcriptase polymerase chain reaction (n=24), which are the key signaling molecules of the Rho-ROCK signal pathway. The protein expression levels of Nogo-A and NgR were detected by Western blot (n=12). The mean optical density in Nogo-A, NgR and Syp was determined by immunohistochemistry (n=18). One-way analysis of variance and LSD-t test were used for statistical analysis.Results(1) Expression of mRNA: the expression levels of Nogo-A, NgR, Rho-A and ROCKⅡ mRNA in fetal rat brain were 4.09±1.34, 3.01±0.77, 39.89±7.71 and 7.82±1.83, respectively in FGR group, and were significantly higher than in control group (1.00±0.13, 1.00±0.10, 1.02±0.30 and 1.00±0.10) (t=4.735, 5.204, 7.682 and 10.675, allP<0.05). The expressions in taurine group (1.07±0.30, 1.20±0.27, 5.36±0.41 and 1.89±0.43) were significantly lower than in FGR group (t=4.645, 4.690, 6.687 and 9.485, allP<0.05), and there was no statistical difference between taurine group and control group (allP>0.05). (2) Expression of protein by Western blot: the expressions of Nogo-A and NgR protein in fetal rat brain were 1.51±0.09 and 0.31±0.05 in FGR group, 0.82±0.06 and 0.06±0.01 in taurine group, and 1.04±0.10 and 0.09±0.12 in control group. The expression was significantly higher in FGR group than in control group (t=9.644 and 5.285, bothP<0.05). The expression was significantly lower in taurine group than in FGR group (t=14.163 and 5.825, bothP<0.05), and there was no statistical difference between taurine group and control group (allP>0.05). (3) Positive expression of protein: the positive expressions of Nogo-A and NgR protein in fetal rat brain were 0.28±0.06 and 0.11±0.02 in FGR group, 0.10±0.02 and 0.04±0.01 in taurine group, and 0.07±0.01 and 0.04±0.01 in control group. The expression was significantly higher in FGR group than in control group (t=9.778 and 7.645, bothP<0.05). The expression in taurine group was significantly lower than in FGR group (t=8.679 and 7.413, bothP<0.05), and there was no statistical difference between taurine group and control group (bothP>0.05). The positive expression of Syp protein in fetal rat brain was 0.08±0.01 in FGR group, and was significantly lower than in control group (0.16±0.04,t=4.600,P<0.05). The expression in taurine group (0.14±0.36) was significantly higher than in FGR group (t=3.181,P<0.05), and there was no statistical difference between taurine group and control group (P>0.05).ConclusionsPrenatal taurine supplementation can improve neural axon development via down-regulating the expressions of the key molecules of Rho-ROCK signal pathway in fetal rat brain tissue.