Effect of recombinant human granulocyte colony-stimulating factor on Nogo receptor expression in the brain tissues of neonatal rats after hypoxic-ischemic brain damage
10.3760/cma.j.issn.2095-428X.2015.06.015
- VernacularTitle:重组人粒细胞集落刺激因子对缺氧缺血性脑损伤新生大鼠脑组织Nogo受体表达的影响
- Author:
Rong CHEN
;
Xiaojing ZHANG
;
Zhixu HE
- Publication Type:Journal Article
- Keywords:
Recombinant human granulocyte colony-stimulating factor;
Hypoxic ischemic brain damage;
Nogo receptor
- From:
Chinese Journal of Applied Clinical Pediatrics
2015;30(6):456-460
- CountryChina
- Language:Chinese
-
Abstract:
Objective To observe-the different effects of 2 doses recombinant human granulocyte colony-stimulating factors (rhG-CSF) on Nogo receptor(NgR) expression in the brain tissue of neonatal rats after hypoxic-ischemic brain damage(HIBD) at different times in order to reveal the neuroprotective effects of rhG-CSF.Methods Seven-day neonatal Sprague-Dawley(SD) rats were randomly divided into 4 groups by drawing method:sham operation group,model group,low-dose rhG-CSF group and high-dose rhG-CSF group,24 rats in each group.Then each group was divided into 4 subgroups (6 rats in each subgroup)and all rats were exterminated at different times after HIBD(1 d,3 d,7 d and 14 d).In the low-dose rhG-CSF group and high-dose rhG-CSF group,the rats were given daily doses of rhG-CSF 50 μg/kg,100 μg/kg respectively for 7 days by subcutaneous injection immediately after the molding(total 7 injections).In model group,rats received an injection of same amount of 9 g/L saline.In sham operation group,rats received no special treatment.Brain tissues of rats from each group were collected at different time points.The expressions of NgR protein and NgR mRNA in the left brain tissue were detected by immunohistochemistry and real-time fluorescent quantitative polymerase chain reaction (PCR).Results Immunohistochemistry:NgR proteins were constitutively expressed in the cerebral cortex in sham operation group at each time point;compared with sham operation group,the expressions of NgR in model group were increased markedly at each time point (135.67 ± 16.63,173.98 ± 17.82,234.00 ± 14.70,319.59 ± 25.22),and the differences were statistically significant(all P ＜ 0.01);compared with model group,the expressions of NgR in the cerebral cortex in low-dose rhG-CSF group (134.35 ± 8.89,109.04 ± 12.62,75.99 ± 13.39) and high-dose rhG-CSF group (81.38 ± 12.25,80.14 ± 10.50,72.58 ± 13.66) on the 3rd,7th,14th day were reduced significantly (all P ＜ 0.01).Compared with low-dose rhG-CSF group,the protein expressions of NgR in the high-does rhG-CSF group were decreased faster,and had the marked difference on the 3rd,7th day (P ＜ 0.05).Real-time fluorescent quantitative PCR:compared with the sham operation group,the expressions of NgR mRNA increased gradually in the cerebral cortex in the model group (1.34 ± 0.24,1.88 ± 0.27,2.88 ± 0.84,4.26 ± 0.86),the differences in NgR mRNA expression were statistically significant at different times(all P ＜ 0.05) ; compared with model group,the expressions of NgR mRNA in low-dose rhG-CSF group on the 7th (1.08 ± 0.30),14th day (0.93 ± O.26) and high-dose rhG-CSF group on the 3rd (0.61 ± 0.10),7th (0.56 ± 0.28),14th day (0.47 ± 0.12) were significantly different (all P ＜ 0.05).The expressions of low-dose group and high-dose group were reduced gradually.The NgR mRNA expression reduced more quickly in the high-dose group than in the low-dose rhG-CSF group and had substantial difference between two groups in 3 days (P ＜ 0.05).Conclusions The findings suggest that rhG-CSF intervention can reduce the expressions of NgR in the brain tissues of neonatal rats after HIBD,and low-dose rhG-CSF also has neuroprotective effect,but it could be weaker than high-dose rhG-CSF.
