Baicalin, which is a flavonoid, was previously shown to exert neuroprotective effects against ischemic injury and oxidative insults. In this study, baicalin was found to induce neuronal differentiation on both C17.2 NSC and primary mouse NSC originated from hippocampuses of E14.5 mouse embryos. The baicalin-mediated differentiation of C17.2 NSC was noted in dose- and time-dependent manners. Baicalin-treated NSC displayed long processes of neurites. The gene expression of neuronal markers, NF-L, TUBB3 and MAP2 was also significantly increased after treated with 20 to 50 muM baicalin on C17.2 NSC. Treating C17.2 NSC with baicalin significantly increased the number of TUBB3 positive cells by 300%. A significant increase in the gene expression of TUBB3 was also observed on primary NSC upon baicalin treatment at 5 to 10 muM. The number of TUBB3 positive cells was increased by 100% after treating with 10 muM baicalin. C17.2 NSC treated with baicalin also increased the gene expression of GABAergic and serotonergic neuronal subtype specific enzymes GAD1 and TPH1. / Nature provides a vast pool of natural compounds with neuroprotection and neurotrophism. A few of these compounds can induce the differentiation of neural stem cells (NSC). There are ample opportunities to discover more natural compounds with differentiation inducing effect on NSC. One of the objectives of this project is to look for novel natural compounds showing neurogenic effect on NSC. This project has established a platform for screening medicinal materials and natural compounds with neural differentiation promoting effect on C17.2 mouse neural stem cell line. Screening results identified total Sanqi saponins, total Renshen saponins, Huangqin extracts and baicalin as potent candidates for inducing this differentiation of NSC. / This project also aims at characterizing the mechanisms involved in the neuronal differentiation effect of baicalin on NSC. Annotation from microarray analysis indicated that baicalin treatment on C17.2 NSC is related to development of tissue and nervous system. qPCR study attested the increased gene expression of nerve growth factor-beta, neurotrophin-3, pro-neural transcriptional factors Ngn1, Ngn2 and NeuroD2. Western blotting showed that baicalin activated ERK1/2 MAP kinase but not JNK and p38 MAP kinases. / This project demonstrated the neurogenic potential of natural resources on NSC. A novel neuronal induction effect of baicalin on NSC was also demonstrated with its mechanisms characterized. This project also revealed that baicalin can be used for promoting functional recovery of post-ischemia animals. / This study showed for the first time that baicalin exerts neuronal differentiation inducing effect on NSC. Another objective of this project is to study whether baicalin can promote functional recovery of animals with ischemia brain injury. Mice having undergone transient occlusion of the bilateral common carotid arteries with blood-reperfusion to induce global cerebral ischemia were treated with baicalin and/or EGFP-NSC. Ischemia animals received implantation of EGFP-NSC into the caudate putamen and/or intravenous injection of baicalin on alternate days for two-week on day seven post-ischemia displayed significant improvement of the cognitive function in terms of the incident of error and escape time in the water T-maze task compared to the control arm of ischemia mice. Data of the study suggested that the therapeutic effect of baicalin would be comparable to that of neural stem cell transplant in improving the cognitive function in a mouse ischemic stroke model. / Li, Ming. / Adviser: P. C. Shaw. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 199-232). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
| Identifer | oai:union.ndltd.org:cuhk.edu.hk/oai:cuhk-dr:cuhk_344606 |
| Date | January 2009 |
| Contributors | Li, Ming, Chinese University of Hong Kong Graduate School. Division of Life Sciences. |
| Source Sets | The Chinese University of Hong Kong |
| Language | English, Chinese |
| Detected Language | English |
| Type | Text, theses |
| Format | electronic resource, microform, microfiche, 1 online resource (xxvii, 232 leaves : ill. (some col.)) |
| Rights | Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/) |
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