RESUMO
Objective To study the protective effect of recombinant human erythropoietin (EPO) on brain and to explore the changes in the diversity of intestinal microbial flora in neonatal rats with hypoxic-ischemic encephalopathy (HIE) by establishing a neonatal rat model of HIE, and to provide an experimental basis for clinical application of EPO in the treatment of neonatal HIE. Methods The HIE model was established in 7-day-old neonatal SD rats. The rats were randomly divided into the HIE model group, EPO-treated group and control group. The changes of nestin expression were detected by immunohistochemistry. Feces of the rats were collected to detect the changes in intestinal microbial flora by 16s rRNA sequencing. Results The expressions of nestin at the same time point in each group were significantly different (P ＜0. 05). The nestin level in the control group was the lowest, that in the EPO-treated group was the highest, and the HIE model group in between. The Shannon-Wiener index of the HIE model group showed a tendency to decrease compared with the control group. Conclusions Exogenous EPO can promote the growth of neural cells in neonatal rats with HIE, indicating a certain protective effect. Meanwhile, the diversity of intestinal microbial flora of the HIE neonatal rats is also changed.
RESUMO
Objectives To explore the effect of exogenous erythropoietin (EPO) on the expression of glial fibrillary acidic protein (GFAP) in hippocampal CA1 region and 5- bromide -2- uracil (BrdU) in hippocampal DG region in neonatal Wistar rats with hypoxic-ischemic brain damage (HIBD). Methods Forty-eight Wistar rats aged 7 days were randomly divided into HIBD model group and EPO experimental group, and another 24 rats as sham operated group. The HIBD model was established by ligating the right common carotid artery and inhaling hypoxia gas mixture (8％ O2 and 92％ N2) for 2 h. The expression of GFAP in hippocampal CA1 region and the number of BrdU positive cells in the hippocampus were detected by immunohistochemical method on at 14 d, 21 d, and 28 d after operation and compared among three groups. Results On 14 d and 21 d after operation, the expression of GFAP in CA1 region and the number of BrdU positive cells were statistically different among three groups (P<0.01) with EPO experimental group having the highest, HIBD model group having the second highest and sham operation group having the lowest in both, . On 28 d after operation, there was no difference in the expression of GFAP and the number of BrdU positive cells in the DG among three groups (P>0.05). At different time point (14 d, 21 d, 28 d) in every group, the expression of GFAP in CA1 region and the number of BrdU positive cells in DG region were all statistically different (P<0.01), all with the highest on 14 d after operation, second highest on 21 d, and the lowest on 28 d. Conclusions Early administration of exogenous EPO can promote the expression of GFAP in hippocampal CA1 region and increase the number of BrdU positive cells in DG region, which indicates that EPO can promote the proliferation and regeneration of damaged neurons. EPO had neuroprotective effect on neonatal rats with hypoxic-ischemic brain damage.
RESUMO
Objective To explore the effect of progesterone on the expression of O4 and O1 in the white matter of neonatal rat model with periventricular leukomalacia (PVL). Methods 2-day-old neonatal SD rats were randomly divided into model group, experimental group, and sham operation group. Rats' left common carotid artery was ligated and exposed to hypoxia (8%O2+92%N2) for 0.5 h in both the model group and experimental group to build the PVL animal model. The rats in experimental group was injected intraperitoneally with progesterone 10 mg/(kg·d) immediately after cerebral hypoxia ischemia. In sham operation group, rats' left common carotid artery was only isolated without ligation and hypoxia. 1, 4, 7, and 14 days after operation, the pathological changes of brain tissue were compared among three groups. Immunohistochemical staining was used to detect the expression of O1 and O4 in the cerebral cortex of rats in three groups at different time points. Results There were no abnormal pathological changes in the white matter in the sham operation group at each time point. The left ventricular enlargement and periventricular leukomalacia were found in both model and experimental groups, while the pathological damages of white matter in experimental group were significantly lighter than those in model group at each time point. The integral optical density (IOD) of O1 and O4 positive cells in the cerebral cortex of the three groups was gradually increased at day 1, day 4, and day 7 after operation and reached the peak level at day 7 , then was decreased at day 14 after operation. There was statistically significant difference (P<0.01). At day 1, day 4, day 7, and day 14, the integral optical density (IOD) of O1 and O4 positive cells in the cerebral cortex of sham operation group was highest, followed by experimental group and model group, and there was significant difference (P<0.01). Conclusion Progesterone can reduce the pathological damage in the cerebral cortex in neonatal rats with PVL, and promote the expression of O1 and O4 in the periventricular white matter, which can promote the differentiation and maturation of oligodendrocytes.
RESUMO
BACKGROUND:Edaravone as an antioxidant protective effect on nerve cells injured by hydrogen peroxide has been confirmed, but its protective effect on oxidative damage to bone marrow stromal cells has not been reported in-depth. OBJECTIVE:To investigate the regulatory effects of edaravone on oxidative injury to bone marrow stromal cells. METHODS:Bone marrow samples were extracted from the long bone of New Zealand rabbits by the method of washing the pulp cavity, then subjected to the density gradient centrifugation and adherent screening to obtain bone marrow stromal stem cells in vitro. The bone marrow stromal cells at 3 passage were divided into five groups:blank group, treated with low-glucose Dulbecco’s modified Eagle’s medium containing 10%fetal bovine serum and 1%double antibody;dexamethasone group, treated with cellculture medium containing 1×10-7 mol/L dexamethasone;50, 100, 300 mg/L edaravone groups, cultured in cellculture medium containing 1×10-7 mol/L dexamethasone and 50, 100, 300 mg/L edaravone, respectively. After culture, MTT method and flow cytometry were used to detect the proliferative level and cellcycle of cells. RESULTS AND CONCLUSION:Compared with the control and dexamethasone groups, edaravone significantly enhanced the cellproliferation. Edaravone played a protective role in bone marrow stromal cells. When the concentration was 50 mg/L, edaravone began to play a regulatory role (P<0.05), and this effect was certainly associated with the concentration of edaravone. When the concentration was up to 100 mg/L, edaravone showed a better protective role (P<0.01). However, with increasing concentration, this protective effect was not further increased, but decreased slightly. Results indicated that high-concentration dexamethasone can induce oxidative injury to bone marrow stromal cells, and edaravone can protect the cells against this oxidative damage by antioxidant role.