Page 47 - 《南京医科大学学报》自然科学版2026年第2期
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第46卷第2期 汤莉巧,段程伟,陈伟观,等. 下调Dixdc1表达抑制创伤性脑损伤后星形胶质细胞极化[J].
2026年2月 南京医科大学学报(自然科学版),2026,46(2):202-212 ·203 ·
(shRNA)was used to knock down Dixdc1 levels in mouse astrocytes C8⁃D1A. Lipopolysaccharide(LPS)stimulation was then applied
to mimic the activated state of astrocytes in vitro. Western blot was performed to detect expression changes of Dixdc1,GFAP,C3,
S100A10,as well as cell proliferation and migration ⁃ related proteins. Flow cytometry was performed to analyze the cell cycle,
accompanied by Western blot detection of S⁃phase⁃related proteins. RT⁃PCR was used to detect the expression of astrocyte polarization
markers. Cellular immunofluorescence was employed to detect the fluorescence intensity of C3 and S100A10. Additionally,Western
blot was performed to assess the phosphorylation levels of signal transducer and activator of transcription 3(STAT3). Results:
Compared with the Sham group,the protein expression levels of Dixdc1 and GFAP were upregulated in the cerebral cortex of TBI mice.
Dixdc1 was expressed in astrocytes within the peri⁃lesional cortical regions. Following LPS stimulation,the protein expression levels of
both Dixdc1 and GFAP were upregulated in C8⁃D1A cells. Scratch assay and EdU assay demonstrated that knockdown of Dixdc1
suppressed LPS ⁃ induced astrocyte proliferation and migration,downregulated the expression of associated proteins,reduced the
proportion of cells in the S phase of the cell cycle,and decreased CyclinA and CDK2 protein levels. C3 showed elevated expression
levels during the acute phase but declined thereafter,whereas S100A10 demonstrated an inverse temporal pattern. Dixdc1 knockdown
may inhibit LPS⁃induced A1⁃type astrocyte polarization by reducing STAT3 phosphorylation levels,which concurrently downregulated
C3 protein expression and upregulated S100A10 protein expression. Conclusion:Following TBI,Dixdc1 protein expression was
upregulated in astrocytes. Knockdown of Dixdc1 significantly suppressed LPS⁃induced proliferation,migration,cell cycle and STAT3
phosphorylation of A1⁃type astrocytes.
[Key words] traumatic brain injury;astrocytes;proliferation;migration;polarization;Dixdc1
[J Nanjing Med Univ,2026,46(02):202⁃212]
创伤性脑损伤(traumatic brain injury,TBI)是由 斑马鱼Ccd1在人体内的同源蛋白,具有Dishevelled⁃
外部机械力导致颅脑区域的结构和功能完整性受 Axin(DIX)和 coiled⁃coil(MTH)两种结构域的蛋白,
[1]
损,是世界上发病率最高的神经系统疾病之一 ,常 是Wnt信号通路的正调节因子 [11] 。目前关于Dixdc1
造成意识障碍、记忆缺失及神经功能障碍 ,具有较 的研究主要集中在肿瘤方面,但越来越多的研究表
[2]
高的致残率和致死率,导致严重的健康问题和社会 明,Dixdc1 在调节神经发育和神经损伤中发挥重要
[1]
经济负担 。TBI 的病理过程包括原发性损伤导致 作用。如Dixdc1 通过 Wnt/β⁃catenin 信号调节突触
的即时神经功能破坏,和由长期炎症级联反应导致 密度,从而影响精神易感性 [12] ;Dixdc1 通过调节
[3]
的继发性损伤 。 β⁃catenin 磷酸化影响神经系统发育,促进神经细胞
神经炎症是TBI最主要的病理表现之一,抑制或 增殖迁移 [13] ;Dixdc1参与星形胶质细胞的细胞周期,
减缓TBI后的神经炎症对改善TBI患者预后有重要意 促进其增殖 。但Dixdc1在星形胶质细胞极化中的
[14]
[4]
义 。神经炎症可刺激神经胶质细胞(主要是小胶质 分子机制尚不清楚。本研究拟开展相关实验,研究
细胞和星形胶质细胞)活化和炎症因子释放 [5-6] 。星 TBI后星形胶质细胞中Dixdc1的表达变化及其对星
形胶质细胞在中枢神经系统中有绝对的数量优势,几 形胶质细胞增殖、迁移和极化的调控作用。
乎行使所有胶质细胞的功能,包括形成和维持血脑屏
1 材料和方法
障(blood brain barrier,BBB),分泌神经营养因子促进
神经元突触形成等 [7-8] 。脑损伤后,星形胶质细胞转 1.1 材料
变为反应性星形胶质细胞,表现为胞体肥大、增殖加 雄性C57BL/6小鼠(60只,6~8周龄)由南通大学
[9]
剧、炎症介质和神经营养因子的分泌增加 。Lid⁃ 动物实验中心提供。所有动物实验均按照动物伦理委
delow等 发现了星形胶质细胞亚型的存在,证实了 员会批准的方案进行(伦理编号:S20220302⁃005)。小
[10]
脂多糖(lipopolysaccharide,LPS)诱导小胶质细胞分 鼠星形胶质细胞 C8⁃D1A 购自上海中乔新舟公司。
泌白细胞介素(interleukin,IL)⁃1α、肿瘤坏死因子 小鼠原代星形胶质细胞(KGG5468⁃1)购自南京凯基
(tumor necrosis factor,TNF)⁃α等,进而诱导生成神经 生物技术股份有限公司。
毒性A1型星形胶质细胞,促进炎症和损害神经细胞; 补体 3(complement 3,C3)、S100 钙结合蛋白
缺血诱导生成神经保护性A2型星形胶质细胞,促进 A10(S100 calcium binding protein A100,S100A10)、
神经营养因子表达、神经元存活和生长、细胞增殖。 E⁃钙黏蛋白(E⁃Cadherin)、N⁃钙黏蛋白(N⁃Cad⁃
DIX域蛋白1(DIX domain containing 1,Dixdc1)是 herin)、波形蛋白(Vimentin)、细胞周期蛋白依赖性

