广州管圆线虫侵入机制研究

项目名称： 广州管圆线虫侵入机制研究

项目编号： No.30800963

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 谭峰

作者单位： 温州医科大学

项目金额： 15万元

中文摘要： 广州管圆线虫感染后，宿主可出现血脑屏障功能障碍、通透性增加，但相关机理并不明确。为此，本研究通过两部分实验进行研究：（1）建立广州管圆线虫幼虫实验感染小鼠模型，对其脑组织中细胞凋亡情况进行检测。结果表明：与对照组相比，实验组小鼠脑组织出现了明显的细胞凋亡现象。TUNEL检测发现，凋亡主要位于小鼠的大脑、小脑及脑干，其细胞凋亡率分别为20%、50% 与70%。Western-blot结果进一步证实随着幼虫感染小鼠时间的增加，leaved Caspase3表达量也增加。（2）构建小鼠血脑屏障体外培养模型，该模型由小鼠脑微血管内皮细胞（BMECs）与脑星形胶质细胞（BACs）共培养所获得。通过4小时渗滤实验与HRP通透性实验，我们发现与对照组相比，广州管圆线虫幼虫提取液作用的实验组中，血脑屏障模型的通透性显著增加。TUNEL法与annexin-V-FITC/PI法均证实广州管圆线虫幼虫提取液可诱导BMECs与BACs发生细胞凋亡。因此，我们认为在广州管圆线虫感染所致宿主血脑屏障功能障碍过程中，由幼虫诱导的细胞凋亡发挥着重要作用。此研究结果将对治疗、预防由广州管圆线虫病提供新的思路。

中文关键词： 广州管圆线虫；幼虫；血脑屏障；细胞凋亡；功能障碍

英文摘要： Blood-brain barrier (BBB) dysfunction may be involved in the pathological changes associated with angiostrongyliasis. However, there is a paucity of information on how A. cantonensis larvae enter the brain and how they interact with BBB tissue to induce significant BBB dysfunction. Here, we researched this mechanism through two studies: (1)To construct mice model infected experimentally A. cantonensis larvae and detect the apoptosis of mice brain tissue. The results shown that the apoptosis of mice brain tissue induced by larvae were significance than that of the normal mice. At different part of infected mice brain tissue section such as cerebrum and cerebellum and brain stem, the apoptosis ratio was 20%, 50% and 70% by TUNEL method, respectively. Western-blot discovered that the leaved caspase3 increased with the extension of infected time; (2)Based on an in vitro mouse BBB model consisting of primary culture brain microvascular endothelial cells (BMECs) and brain astrocytic cells (BACs). In these studies, a four-hour percolation and HRP permeability experiment showed that A. cantonensis larvae extracts can increase the permeability of the BBB. Apoptosis among BMECs and BACs after exposure to larvae extracts was monitored by TUNEL and annexin-V-FITC/PI double staining. A. cantonensis larvae extracts were found to induce apoptosis in both BMECs and BACs. For these reasons, we concluded that the induction of apoptosis might participate in the BBB dysfunction observed during angiostrongyliasis. Improved fundamental understanding of how A. cantonensis induces apoptosis may lead to new approaches to the treatment or prevention of this deadly parasitic disease.

英文关键词： Angiostrongylus cantonensis; larva; blood-brain barrier; apoptosis; dysfunction