VEGF 单基因治疗大鼠脑缺血的效果

摘要

Objective :To explore therapeutic effect of vascular endothelial growth factor (VEGF) monogenic therapy on cerebral ischemia in rats .Methods :A total of 60 healthy adult male Wistar rats were selected ,randomly and e—qually divided into gene therapy group ,blank carrier control group and control group .Local cerebral ischemia／reperfusion model was established in all rats .Gene therapy group received injection of type I recombinant adeno—as—sociated virus vector carrying therapeutic gene hVEGF165 (rAAV1－VEGF) ,blank carrier group received injection of blank rAAV1 (rAAV1－null) and control group received injection of normal saline .VEGF levels in cerebrospinal fluid and brain tissue ,intracranial pressure ,water content of brain tissue ,edema brain volume ,and microvascular density were measured and compared among all groups .Results :Compared with control group and blank carrier con—trol group on 24h after I／R ,there were significant rise in VEGF levels of cerebrospinal fluid and brain tissue [cere— brospinal fluid :(0.64 ± 0.11) pg／ml ,(0.63 ± 0.12) pg／ml vs.(73.10 ± 9.70) pg／ml ,brain tissue :[ (6. 81 ± 1. 33) pg／ml ,(6.64 ± 1. 30) pg／ml vs.(578. 20 ± 78.36) pg／ml] ,intracranial pressure [ (14. 10 ± 1.63) mmHg ,(14. 62 ± 1.57) mmHg vs.(25. 81 ± 2.05) mmHg] ,brain water content [ (79. 02 ± 1.04))%,(79.81 ± 1.10)% vs.(85. 82 ± 1.02)%] ,edema brain volume [ (170.04 ± 13. 02) mm3 ,(173.13 ± 14.20) mm3 vs.(404.22 ± 20.15) mm3 ] and brain microvascular density [ (106025. 17 ± 13320.11) m2／mm2 ,(106103.11 ± 14022. 57) m2／mm2 vs.(140331. 21 ± 13892.05) m2／mm2 ] in gene therapy group , P＝0. 001 all.Conclusion :Treatment with carrier rAAV1－VEGF can increase intracranial VEGF level and promote brain microvascular proliferation in rats .Meanwhile ,it will induce rise of brain water content of ischemic hemisphere and edema brain volume ,resulting in intracranial pressure rise .%目的:探讨血管内皮生长因子(VEGF)单基因治疗大鼠脑缺血的效果.方法:选择健康成年雄性Wistar大鼠60只,随机分为基因治疗组,空白载体对照组和对照组,每组20只,所有大鼠均建立局灶性脑缺血再灌注模型,基因治疗组给予注射携带治疗基因hVEGF165的Ⅰ型重组腺相关病毒载体(rAAV1—VEGF) ,空白载体组给予注射rAAV1—null ,对照组给予注射生理盐水,检测脑脊液和脑组织VEGF水平,测定各组大鼠颅内压、脑组织含水量和水肿脑体积,并观察各组微血管密度.结果:缺血再灌注后24h ,与对照组和空白载体对照组比较,基因治疗组脑脊液和脑组织VEGF水平[脑脊液: (0.64 ± 0.11) pg／ml 、 (0.63 ± 0. 12) pg／ml比(73.10 ± 9.70) pg／ml ,脑组织[ (6.81 ± 1.33) pg／ml 、 (6.64 ± 1. 30) pg／ml比(578. 20 ± 78.36) pg／ml]显著升高,颅内压[(14. 10 ± 1.63) mmHg 、 (14. 62 ± 1.57) mmHg比(25.81 ± 2.05) mmHg] 、脑水含量[(79.02 ± 1. 04))%、(79. 81 ± 1.10)%比(85. 82 ± 1.02)%] 、水肿脑体积[(170. 04 ± 13.02) mm3 、(173. 13 ± 14.20) mm3比(404. 22 ± 20.15) mm3 ]和脑微血管密度[(106025. 17 ± 13320. 11 ) m2／mm2 、 (106103. 11 ± 14022. 57) m2／mm2比(140331.21 ± 13892. 05) m2／mm2 ]均显著增加( P均＝0. 001) .结论:通过载体rAAV1—VEGF给予治疗可使大鼠脑内VEGF水平增加,并促进脑内微血管增殖,但同时会诱发缺血半球脑水含量增加,水肿脑体积增大,引起颅内压升高.