PolyU IR
 

PolyU Institutional Repository >
Applied Biology and Chemical Technology >
ABCT Theses >

Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/4051

Title: Neuroprotective effect by Z-ligustilide extracted from Radix Angelica sinensis for the treatment of cerebral ischemia
Authors: Du, Junrong
Subjects: Hong Kong Polytechnic University -- Dissertations
Nervous system -- Diseases -- Chemotherapy
Cerebral ischemia -- Chemoprevention
Issue Date: 2006
Publisher: The Hong Kong Polytechnic University
Abstract: Stroke resulting from cerebral ischemia is one of the leading causes of death and disability. To date, there is not yet any neuroprotective agent for the treatment of stroke. Involvement of oxidative stress in ischemic brain damage is established (Cassarino and Bennett, 1999; Simonian and Coyle, 1996). The overproduction of reactive oxygen species (ROS) such as superoxide anino, hydroxyl radical, and nitric oxide can directly react with and damage biomacromolecules by virtue of their reactivity that leads to neuronal cell death through necrosis, or, if in less intense cases, may mediate neuronal apoptosis through a cascade of biochemical process following cerebral ischemia (Li, et al., 1995; Ratan et al., 1994; Whittemore et al., 1995). Therefore, lipophilic antioxidants are of neuroprotective potential in the development of ischemic brain damage. Z-ligustilide (3-butylidene-4, 5-dihydro-phthalide, LIG) is a highly lipophilic compound extracted from Radix Angelica sinensis (Oliv.) Diels (Umbelliferae), known as Danggui in Chinese. Previous studies have shown that LIG has various bioactivities. Studies in this thesis evaluated, for the first time, the neuroprotective effect and the associated mechanisms of LIG in cerebral ischemia. In order to design the dosage regimen of LIG in vivo, its cellular permeability and transport pathways were first determined in Caco-2 monolayers. Our results show that oral application is the preferred route for the systemic administration of LIG. The free radical scavenging efficacy and the antioxidant activities of LIG were then evaluated in different in vitro ROS reactive systems, hydrogen peroxide-damaged C6 glioma cells and forebrain ischemic mice, respectively. We ascertain that LIG is a novel antioxidant and has significant protective effects against oxidative injury. The neuroprotective effects of LIG have been proven in transient forebrain ischemic mice and focal ischemic rats by measuring the histological, physiological, neurological or biochemical improvements after cerebral ischemia. The results suggest that postischemic treatment with LIG significantly ameliorates infarction volume by inhibiting both the apoptotic and necrotic cell death, and improving neurological deficits after transient cerebral ischemia. In addition, the multiple mechanisms, including the antioxidant, anti-apoptotic, and anti-inflammation properties, contribute to the neuroprotection of LIG. This thesis consists of 7 chapters, beginning with a general introduction, and then followed by the methodology section. There are then four chapters on results, and at the end, there is a general discussion.
Degree: Ph.D., Dept. of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, 2006
Description: 338 leaves : ill. (some col.) ; 30 cm.
PolyU Library Call No.: [THS] LG51 .H577P ABCT 2006 Du
Rights: All rights reserved.
Type: Thesis
URI: http://hdl.handle.net/10397/4051
Appears in Collections:ABCT Theses
PolyU Electronic Theses

Files in This Item:

File Description SizeFormat
b19736423_ir.pdfFor All Users (Non-printable) 3.85 MBAdobe PDFView/Open
b19736423_link.htmFor PolyU Users 161 BHTMLView/Open



Facebook Facebook del.icio.us del.icio.us LinkedIn LinkedIn


All items in the PolyU Institutional Repository are protected by copyright, with all rights reserved, unless otherwise indicated.
No item in the PolyU IR may be reproduced for commercial or resale purposes.

 

© Pao Yue-kong Library, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
Powered by DSpace (Version 1.5.2)  © MIT and HP
Feedback | Privacy Policy Statement | Copyright & Restrictions - Feedback