Cell proliferation and nestin expression in cortex and SEZ of MCAO rats

AIM:To explore the effect of brain ischemia injury on cell proliferation and nestin expression in cortex and subependymal zone (SEZ).METHODS:Using a local brain ischemia model(MCAO), BrdU positive cells of cortex and subependymal zone (SEZ), also nestin positive cells, were observed by immunohistochemistry.RESULTS:BrdU and nestin positive cells in SEZ of MCAO rats were obviously increased. In cortex, only nestin positive cells were observed.CONCLUSION:Neural stem cells in SEZ and cortex were activated after brain ischemia, it may be related with neural recovery after brain ischemia injury.     

A reactive pattern of ischemia-induced nestin protein in the rat brain

AIM:To explore the expressive profile of nestin protein in the focal ischemic brain and to study the recovery mechanism of brain focal infarct.METHODS:Cellular morphology,time-course and distribution pattern of nestin positive response were immunohistochemically examined in different brain regions of 36 adult male SD rats. RESULTS:Nestin positive response of different brain regions in sham operated rats was present in small- and micro-vasculartures and the third ventricle bottom and ependyma. A large number of nestin positive cells were detected in ischemic brain, and were more remarkable in the cortical areas of parietal lobe and preoptic area as well as ischemic caudoputamen. Stellate nestin positive cells were located in the deep layer of ischemic cortex, but fibrillary cells were located in the shallow layer. Nestin positive cells in the ischemic caudoputamen showed the same changes of morphology as those cells in the deep layer of ischemic cortex. Morphological and number alterations of nestin positive cells were the most remarkable at 1 weeks post-ischemia, which showed more hypertrophy and proliferation in morphology, and a marked increase in number was present in the ischemic cerebral cortex and the ischemic caudoputamen. These alterations of nestin positive cells persisted up to 6 weeks post-ischemia, and then, the nestin positive response in the ischemic brain decreased gradually.CONCLUSION:Focal cerebral ischemia induces nestin re-expression on reactive astrocytes, which may be very important to the self-recovery of cerebral infarct.     

神经节苷脂对脑瘫大鼠大脑皮质区Nestin、NGF表达的影响

目的 观察神经节苷脂(GM1)对脑瘫大鼠大脑皮质区神经巢蛋白(Nestin)、神经生长因子(NGF)表达的影响,探讨GM1促进脑瘫神经修复的可能机制.方法 选择出生10周雄性SD大鼠200只,随机分为3组:假手术组60只,脑瘫模型140只,再分为模型组70只,腹腔注射生理盐水;GM1组70只,腹腔注射GM1.分别在术后0～24 h的7个时间点利用酶联免疫法检测大鼠大脑皮质区Nestin、NGF表达情况,并在实验前和后1～4 d观察大鼠的体质量变化情况.结果 (1)大鼠大脑皮质区Nestin表达GM1组0～24 h、模型组0～12 h明显高于假手术组(P＜0.01);GM1组16～24 h明显高于模型组(P＜0.01).(2)GM1组大鼠大脑皮质区NGF表达0～24 h明显高于模型组(P＜0.05)和假手术组(P＜0.01).模型组NGF表达仅0、4、8h高于假手术组(P＜0.05).(3)GM1组术后第1、2天体质量缓慢增加,至第3、4天明显高于模型组(P＜0.05),接近假手术组(P＞0.05),模型组体质量增加不明显.结论 预防性使用GM1是通过增强大脑皮质的Nestin和NGF表达并延长表达时间来发挥其对实验性脑瘫大鼠的神经保护作用.     

Relationship between MAP-2, nestin and development of muscular layer of human embryonic esophagus

AIM: To explore the relationship between microtubule-associated protein 2 (MAP-2), nestin and development of esophageal muscular layer in human embryos. METHODS: At the second to fourth month of gestation, the protein expression of MAP-2 and nestin was observed using the PV method of immunohistochemistry in the human embryonic esophageal tissues. RESULTS: At the second month, the third month and the fourth month of gestation, MAP-2 positive expression in the neural cells of the intermuscular nerve plexus, and negative expression in the muscle cells of human embryonic developing esophageal muscle were observed. Nestin positive expression was found in the muscle cells at the second month to the third month of gestation. However, no nestin expression in the muscle cells of the esophageal muscle at the fourth month of gestation was observed. At the second month to the fourth month of gestation, nestin showed negative or weak positive expression in the neural cells of the intermuscular nerve plexus of human embryonic esophageal tissues. CONCLUSION: MAP-2 and nestin might regulate the formation of esophageal muscular layer in human embryos.     

Effects of siRNA-mediated nestin silencing on invasion and migration of human esophageal cancer ECA109 cells

AIM: To investigate the effect of small interference RNA(siRNA)-mediated silencing of nestin gene on the invasion and migration of human esophageal cancer ECA109 cells and the possible mechanism. METHODS: The esophageal cell line ECA109 was transfected with siRNA targeting nestin and the cell invasion and migration abilities were observed. The expression of nestin, MMP2, MMP9, VEGF, and total and nuclear β-catenin proteins in the transfec-ted cells were determined by real-time PCR and Western blot. RESULTS: Compared with control group, the expression of nestin at mRNA and protein levels was significantly down-regulated in the ECA109 cells transfected with nestin-siRNA, so was the expression of MMP2, MMP9, VEGF, and total and nuclear β-catenin proteins. The levels of invasion and migration capacities of ECA109 cells transfected with nestin-siRNA were lower than those in the cells transfected with control-siRNA. CONCLUSION: Knockdown of nestin expression significantly inhibits the invasion and migration of the esophageal cancer cells, which may act via suppressing β-catenin translocation to the nucleus and influencing the expression of MMP2, MMP9 and VEGF.     

椎间盘脱出模型大鼠脊髓巢蛋白和音猬因子变化及电针效应

[目的]研究椎间盘脱出模型大鼠脊髓巢蛋白(Nestin)和音猬因子(SHH)变化及电针效应,分析神经组织代偿性修复的机理.[方法]大鼠随机分为空白组(n=9)、模型组(n=15)和电针组(n=15),在T13段脊髓左腹侧填塞硅胶片建立椎间盘脱出模型.模型建立后4、7、14 d处死大鼠取压迫部位脊髓组织,荧光抗体法观察Nestin阳性细胞数量,ELISA法检测Nestin和SHH含量.[结果]14d时,与模型组相比,电针组运动机能评分极显著升高(P＜0.01),SHH含量和Nestin阳性细胞数量极显著升高(P＜0.01),Nestin含量显著升高(P＜0.05).[结论]本研究成功建立椎间盘脱出模型,脊髓受压后自我修复过程中可表达Nestin.电针干预后大鼠运动机能极显著改善,提示其与电针升高Nestin和SHH含量有关.     

Expression of microtubule-associated protein 2 and nestin in small intestine tissues of human embryos

AIM: To explore the relationship between expression of microtubule-associated protein 2 (MAP-2)/nestin and development of small intestine in human embryos. METHODS: The expression of MAP-2 and nestin proteins was detected in the second, third and fourth months of fetal human embryonic small intestinal tissues by the PV method of immunohistochemistry. The positive cell counts and positive intensities were analyzed with Nikon imaging system (NIS-DR). One-way ANOVA was applied to compare these positive cell counts and positive intensities. RESULTS: At the second, the third and the fourth month of human embryos, MAP-2 positive expression was observed in the neural cells and neural fibers of the intermuscular nerve plexus and submucosal plexus in the developing small intestines. With the fetal age increasing, the expressive intensity of MAP-2 positive cells in the neural tissues of the intermuscular nerve plexus showed an uptrend. The results of positive intensity values of the MAP-2 positive cells detected in the 3 fetal age periods showed significant difference (P<0.05). Nestin positive expression was seen in all layers of the small intestine, and the number of positive cells was first increased and then decreased in the developing small intestines of human embryos with the increasing fetal age. One-way ANOVA results also showed significant difference (P<0.05). CONCLUSION: MAP-2 and nestin regulate the development of small intestinal tissues in human embryos.