A20基因对大鼠颅脑损伤的治疗作用

Gene therapy for traumatic brain injury with A20 in rats

目的研究A20基因住创伤性颅脑损伤（traumaticbraininjmy，TBI））中的抗凋亡脑保护作用。方法实验组与对照组各35只SD大鼠，制作重度TBI模型后，实验组与对照组分别在伤后30min，在立体定向仪下向损伤灶周边皮质及损伤灶内多点注射脂质体-pcDNA3．1-A20和脂质体-pcDNA3．1空质粒。两组分别于术后12，24，48，72，168h各取5只大鼠取脑制作切片，免疫组化法检测A20基因的表达和损伤后细胞凋亡的情况；每组剩余的另10只大鼠于TBI后第1，2，3，4周，进行斜板试验测试其神经功能。结果（1）实验组损伤灶周边A20表达显著高于对照组（P〈0．01）。（2）TBI后可见损伤侧皮质、海马分布有不同数量的凋亡细胞，以损伤灶周围皮质最为集中；两组的细胞凋亡均在TBI后72h达到高峰。实验组TBI后12，24，48及72h神经凋亡数量较对照组明显降低（P〈0．01或0．05）。（3）伤后第4周，实验组临界角度大于对照组（P〈0．05）。结论脂质体介导的A20基㈨治疗能够起到抗损伤后细胞凋亡的神经保护作用。

Objective To investigate the anti-apoptotic effect of gene A20 in treatment of traumatic brain injury （TBI）. Methods Thirty-five Sprague-Dawley rats were made severe TBI models and assigned randomly to experimental group and control group （35 rats in each group）. After severe TBI, the rats in experimental group were injected with liposome-pcDNA3. 1-A20 and those in control group injected with liposome pcDNA3, 1-A20 at 30 minutes after severe TBI. The animals in both groups were sacrificed to remove the brain of five rats from each group at 12, 24, 48, 72 and 168 hours for sectioning. The expression of A20 and neurocyte apoptosis were defined by immunohistological method and TUNEL accordingly. The other ten rats were testified for neurological function at 1 , 2, 3 and 4 weeks after TBI. Results The expression of A20 in experimental group was higher than that in control group, with statistical differences （P 〈 0.01 ）. The peak neuroeyte apoptosis was found at 72 hours after TBI. The number of apoptosis cells in experimental group was lower than that in control group at 12, 24, 48 and 72 hours afte TBI （P 〈 0.01 or 0.05 ）. At the 4th week after TBI, the neurological function in experimental group was better than that in control group （ P 〈 0.05 ）. Conclusion Gene therapy with A20 may have anti-apoptosis effect and exert neuroprotective effect on severe TBI.