小胶质细胞极化在亚低温治疗热射病诱发认知功能障碍中的作用

目的 探究亚低温对热射病治疗的作用与小胶质细胞极化的改变。方法 将72只小鼠分为对照组,模型组,IL-4组与亚低温组。取非对照组小鼠构建热射病模型,观察小鼠核心温度变化,统计小鼠的存活率。次日开展Morris水迷宫实验评估小鼠认知功能,取小鼠脑组织用于苏木精-伊红染色、免疫组化染色和荧光定量PCR。结果 模型组小鼠出现4只死亡,与对照组相比,模型组小鼠Morris水迷宫中逃避潜伏期增加,穿越平台次数减少。苏木精-伊红染色中神经元状态受损,免疫组化染色中iba1表达增加。M1型小胶质细胞极化标记物CD16、TNF-α、IL-1β与iNOS表达明显升高,M2型小胶质细胞极化标记物CD206、TGF-β、Arg1与YM-1表达虽然有升高,但差异无统计学意义。IL-4组小鼠死亡3只,亚低温组小鼠死亡1只,与模型组相比,IL-4与亚低温组小鼠逃避潜伏期减少,穿越平台次数增加。苏木精-伊红染色显示神经元状态恢复,免疫组化显示iba1表达减少。M1型小胶质细胞除极标记物CD16、TNF-α、IL-1β与iNOS表达降低,M2型小胶质细胞极化标记物CD206、TGF-β、Arg1与YM-1表达升高。结...     

电针对Beagle犬展神经损伤后小胶质细胞活化状态的影响

目的通过进行Beagle犬展神经损伤模型制作,探讨展神经损伤后小胶质细胞表型变化及电针刺激后小胶质细胞活化状态的改变。方法选用健康雄性成年Beagle犬随机分为三组:假手术组(A)、损伤组(B)和电针处理组(C)。A组仅进行展神经游离,B组、C组均进行展神经损伤模型制作,C组进行展神经刺激电极及外直肌记录电极植入。术后4 w后均取材进行Western Blot检测,分析展神经小胶质细胞M1、M2型标志分子的表达水平,进行统计学分析。结果与损伤组相比,电针组M1型表达分子i NOS及IL-1β表达均降低(P 0. 05);而电针组M2型表达分子Arginase及BDNF表达较损伤组均增加(P 0. 05)。结论展神经损伤后以M1型标志分子为主,电针刺激能够显著升高M2型转化。     

小鼠脑出血后不同时间点小胶质细胞极化状态的实验研究

目的 观察小鼠脑出血后不同时间点小胶质细胞M1及M2型的转化，为促炎型M1型小胶质细胞向抗 炎修复型M2型小胶质细胞的转化，减轻脑出血后神经功能损伤提供理论依据。 方法 选取健康雄性ICR小鼠48只，随机分为假手术组、脑出血组，每组按术后时间点不同随机 分为1 d、3 d、7 d三个时间点，每个时间点8只。通过立体定位仪用微量注射器向尾状核注射Ⅳ型胶 原酶0.5 U制备脑出血模型，假手术组注射等量生理盐水。各组于术后对应时间点参照改良Garcia 评分量表进行神经功能缺损评分后灌注取脑，采用蛋白免疫印迹检测M1型小胶质细胞标志物肿瘤 坏死因子α（tumor necrosis factor-α，TNF-α）、白细胞介素6（interleukin-6，IL-6），M2型小胶质细胞 标志物脑源性神经营养因子（brai n-derived neurotrophic factor，BDNF）、胰岛素样生长因子1（insulinlike growth factor 1，IGF-1）的含量；采用免疫荧光染色标记小胶质细胞M1型（Iba1+CD80）、M2型 （Iba1+CD206），评价出血后血肿周围组织小胶质细胞活化状态。 结果 脑出血组1 d、3 d、7 d各时间点Garci a评分均较假手术组低，TNF-α、IL-6、BDNF及I GF-1的蛋白 表达量均较假手术组增多（均P＜0.01）。脑出血后1 d时M1型高于M2型小胶质细胞数量（38.33±1.53 vs 23.00±3.00，P =0.01）；3 d时M1型同样高于M2型（66.33±3.06 vs 57.33±2.52，P =0.02）；7 d时M1 型低于M2型（33.67±1.15 vs 52.33±0.58，P＜0.01）。 结论 脑出血急性期（1～3 d）以M1型小胶质细胞为主，脑出血亚急性期（7 d）以M2型小胶质细胞 为主。     

电针诱导大麻素受体表达参与展神经修复的相关研究

目的探讨电针是否通过大麻素受体介导调控小胶质细胞活化促进损伤展神经修复。 方法选用健康雄性成年Beagle犬25只随机分为5组：假手术组（A组）、损伤组（B组）、电针处理组（C组）、拮抗剂组（D组）、溶剂组（E组）。将Beagle犬麻醉后,A组仅暴露分离展神经,在其他组电针刺激时进行束缚;B组制作展神经损伤模型,在其他组电针刺激时进行束缚;C组在展神经损伤模型建立后进行电针刺激;D组损伤模型成功后进行AM630注射并予以电针刺激;E组操作同D组,在每次电针刺激前给予溶剂进行腹腔注射。运用Western blot检测A、B、C 3组小胶质细胞大麻素1型受体（CB1R）、CB2R表达,进一步试验取材运用免疫荧光分析5组CB2R表达的情况,并进行统计学差异分析。 结果Western blot检测显示,B、C组分别与A组比较,CB1R蛋白的表达量差异均无统计学意义（P>0.05）;电针预处理持续15 min连续2周后,C组CB2R的蛋白表达量显著高于A组,差异有统计学意义（P<0.05）,而A组与B组间差异无明显统计学意义（P>0.05）。免疫荧光显示,C、E组分别与A组比较,Arginse/CD11b差异均有统计学意义（P<0.05）。 结论CB2R主要参与电针刺激诱导神经损伤保护作用;电针能够通过CB2R调控小胶质活化状态促进损伤展神经修复。     

小鼠脑出血后不同时间点小胶质细胞极化状态的实验研究

目的 观察小鼠脑出血后不同时间点小胶质细胞M1及M2型的转化，为促炎型M1型小胶质细胞向抗
炎修复型M2型小胶质细胞的转化，减轻脑出血后神经功能损伤提供理论依据。
方法 选取健康雄性ICR小鼠48只，随机分为假手术组、脑出血组，每组按术后时间点不同随机
分为1 d、3 d、7 d三个时间点，每个时间点8只。通过立体定位仪用微量注射器向尾状核注射Ⅳ型胶
原酶0.5 U制备脑出血模型，假手术组注射等量生理盐水。各组于术后对应时间点参照改良Garcia
评分量表进行神经功能缺损评分后灌注取脑，采用蛋白免疫印迹检测M1型小胶质细胞标志物肿瘤
坏死因子α（tumor necrosis factor-α，TNF-α）、白细胞介素6（interleukin-6，IL-6），M2型小胶质细胞
标志物脑源性神经营养因子（brai n-derived neurotrophic factor，BDNF）、胰岛素样生长因子1（insulinlike
growth factor 1，IGF-1）的含量；采用免疫荧光染色标记小胶质细胞M1型（Iba1+CD80）、M2型
（Iba1+CD206），评价出血后血肿周围组织小胶质细胞活化状态。
结果 脑出血组1 d、3 d、7 d各时间点Garci a评分均较假手术组低，TNF-α、IL-6、BDNF及I GF-1的蛋白
表达量均较假手术组增多（均P＜0.01）。脑出血后1 d时M1型高于M2型小胶质细胞数量（38.33±1.53
vs 23.00±3.00，P =0.01）；3 d时M1型同样高于M2型（66.33±3.06 vs 57.33±2.52，P =0.02）；7 d时M1
型低于M2型（33.67±1.15 vs 52.33±0.58，P＜0.01）。
结论 脑出血急性期（1～3 d）以M1型小胶质细胞为主，脑出血亚急性期（7 d）以M2型小胶质细胞
为主。     

miR-146a通过TLR4/NF-κB通路调节小胶质细胞/巨噬细胞极化对缺血性脑卒中的保护作用

目的 探讨微小RNA-146a(MicroRNA-146a,miR-146a)在缺血性脑卒中小胶质细胞/巨噬细胞极化中的作用及其潜在机制。方法 构建大脑中动脉闭塞(Middle cerebral artery occlusion,MCAO)模型,脑内注射阴性对照物(Negative control mimic,NC mimic)或miR-146a mimic; 构建BV2小鼠小胶质细胞(BV2 mouse microglia,BV2)缺血缺氧(Oxygen glucose deprivation,OGD)模型,将NC mimic,miR-146a mimic转染至OGD处理的BV2细胞中,进行改良神经功能缺损评分(Modified neurological severity scores,mNSS)评估神经功能; 2,3,5-氯化三苯基四氮唑(2,3,5-Triphenyltetrazolium chloride,TTC)染色检测脑梗死体积; 实时荧光定量聚合酶链反应(Real time quantification polymerase chain reaction,RT-qPCR)检测脑组织及细胞中的miR-146a、单核细胞趋化蛋白1(Monocyte chemotactic protein 1,MCP-1)、诱导型一氧化氮合酶(Inducible nitric oxide synthase,iNOS)、白细胞介素-10(Interleukin-10,IL-10)和精氨酸酶-1(Arginase-1,Arg1)mRNA水平; 免疫荧光染色检测小胶质细胞M1/M2极化标志物; 蛋白质免疫印迹(Western blot)检测细胞中Toll样受体4(Toll-like receptor 4,TLR4)/核转录因子κB(Nuclear transciption factor kappa B,NF-κB)通路蛋白的表达水平; 双荧光素酶报告基因检测miR-146a与肿瘤坏死因子受体相关因子6(TNF receptor associated factor 6,TRAF6)的靶向关系。结果 与假手术(Sham)组比较,MCAO组大鼠脑组织中miR-146a表达水平显著降低,mNSS评分和脑梗死体积显著升高,CD16⁺Iba-1⁺细胞和CD206⁺Iba-1⁺细胞数量均增加,M1标志物MCP-1,iNOS和M2标志物IL-10,Arginase-1 mRNA水平均显著升高,而过表达miR-146a后mNSS评分和脑梗死体积显著降低,M1极化标志物水平降低,M2极化标志物水平升高(P<0.05)。与对照(Control)组比较,OGD组BV2小胶质细胞中的miR-146a表达水平显著降低,集群分化因子16(Cluster of differentiation 16,CD16)⁺离子钙接头蛋白分子-1(Ionized calcium bindingad aptormolecule-1,Iba-1)⁺和集群分化因子206(Cluster of differentiation 206,CD206)⁺Iba-1⁺细胞数量均增加,MCP-1,iNOS,IL-10和Arginase-1 mRNA水平均显著升高,TLR4/NF-κB通路相关蛋白表达水平均显著升高; 与OGD+NC mimic组比较,OGD+miR-146a mimic组细胞中的miR-146a表达水平显著升高,M1极化标志物水平降低,M2极化标志物水平升高,TLR4/NF-κB通路相关蛋白表达水平均显著降低(P<0.05)。结论 miR-146a通过TLR4/NF-κB通路来促进缺血性脑卒中后M2极化,从而发挥神经保护作用。     

长春西汀注射液在小鼠永久性脑缺血小胶质细胞表型转化中的作用研究

目的 研究长春西汀注射液对小鼠永久性大脑中动脉远端缺血后神经功能恢复及小胶质细胞表型 转化的影响。 方法 36只雄性C57BL/6J小鼠随机分为永久性脑缺血组6只、生理盐水组12只、长春西汀组12只和 假手术组6只,前三组用高频电刀凝断小鼠右侧大脑中动脉远端,制作永久脑缺血模型,假手术组 仅暴露大脑中动脉远端,不凝断血管。模型成功后,生理盐水组尾静脉注射生理盐水,每次150 μL, 每天1次,持续14 d;长春西汀组尾静脉注射长春西汀注射液,每次150 μL（4.55 mg/kg）,每天1次, 持续14 d。模型成功后3 d、5 d、7 d、9 d、11 d和14 d进行改良加西亚评分和转棒测试评价小鼠感觉和 运动神经功能;模型成功后14 d用免疫荧光标记神经元,评价各组神经元损伤情况,免疫荧光染色 梗死周围小胶质细胞表型标志物Iba1、CD16/32和CD206的表达,评价M1型（Iba1及CD16/32阳性）和 M2型（Iba1及CD206阳性）小胶质细胞表型转化情况。 结果 长春西汀组小鼠模型成功后11 d和14 d的改良加西亚评分和14 d的转棒测试中的时间及速度 测试结果均优于永久性脑缺血组,差异均有统计学意义。长春西汀组14 d时神经元损伤较永久性脑 缺血组（P =0.008）和生理盐水组（P =0.037）减轻。永久缺血组（P <0.001）和生理盐水组（P =0.005） M1型小胶质细胞表达高于假手术组;长春西汀组M1型小胶质细胞表达低于永久缺血组（P <0.001） 和生理盐水组（P =0.038）。长春西汀组M2型小胶质细胞表达高于假手术组、永久性脑缺血组和生 理盐水组（均P <0.001）。 结论 长春西汀注射液可能通过促进小胶质细胞表型由促炎向抗炎转变,减少神经元损伤,从而 在小鼠永久性脑缺血后发挥神经保护和促进功能恢复的作用。     

lncRNA NEAT1沉默通过IL-10/STAT3信号通路调节小胶质细胞极化对脑缺血再灌注损伤大鼠的影响

目的 探讨长链非编码RNA核富集转录体1(lncRNA NEAT1)沉默通过白细胞介素(IL)-10/信号传导与转录激活因子3(STAT3)信号通路调节小胶质细胞极化对脑缺血再灌注损伤(CIRI)大鼠的影响。方法 SD大鼠随机分为假手术组(Sham组)、CIRI组、CIRI+si-NC组、CIRI+si-NEAT1组,每组24只。除Sham组外,其余各组大鼠采用线栓法构建CIRI模型。建模结束后,各组大鼠给予对应处理7 d。对大鼠神经功能缺损进行评分;观察脑组织病理学变化;检测脑梗死体积百分比,脑组织中离子钙接头蛋白分子1阳性(Iba1+)细胞中M1型、M2型极化标志物阳性(Iba1+CD86+、Iba1+CD206+)细胞的数量,IL-1β、肿瘤坏死因子-α(TNF-α)、IL-4、IL-10,lncRNA NEAT1、诱导型一氧化氮合酶(iNOS)、精氨酸酶-1(Arg-1)、IL-10 mRNA,IL-10、STAT3、磷酸化STAT3(p-STAT3)蛋白水平。结果 与Sham组相比,CIRI组大鼠脑组织病理损伤严重,神经功能缺损评分、脑梗死体积百分比、脑组织中Iba1+CD8...     

lncRNA LINC01089对氧糖剥夺/复氧损伤后小胶质细胞极化的影响

目的 探讨长链非编码RNA（lncRNA） LINC01089对小胶质细胞氧糖剥夺/复氧（OGD/R）损伤后表型和炎症反应的影响及其机制。方法 体外培养小鼠小胶质细胞B-V2细胞,OGD/R损伤后,转染lncRNA LINC01089过表达质粒及其空载质粒、沉默质粒siRNA及阴性对照,以及miR-449c-5p模拟物、抑制剂及其阴性对照寡核苷酸。采用qRT-PCR检测M1型小胶质细胞标记物iNOS mRNA和CD86 mRNA、M2型小胶质细胞标记物Arg1 mRNA和CD206 MRNA、lncRNA LINC01089、miR-449c-5p的表达水平;采用ELISA检测细胞上清液炎性因子的含量;采用免疫印迹法检测细胞STAT6蛋白表达水平。荧光素酶报告基因实验验证lncRNA LINC01089与miR-449c-5p以及miR-449c-5p与STAT6的靶向关系。结果 OGD/R损伤后,B-V2细胞lncRNA LINC01089表达水平显著下调,miR-449c-5p表达水平显著上调。荧光素酶报告基因实验结果显示,lncRNA LINC01089靶向负调控miR-449c-5p表达,miR-449c-5p靶向负调控STAT6表达。过表达lncRNA LINC01089,显著降低M1型标记物iNOS mRNA和CD86 mRNA表达水平及细胞上清液促炎因子IL-1β、IL-6和TNF-α的含量,明显增高M2型标记物Arg-1 mRNA和CD206 mRNA表达水平及细胞上清液抗炎因子IL-4、IL-10和TGF-β的含量。过表达lncRNA LINC01089可靶向负调控B-V2细胞miR-449c-5p表达,促进STAT6蛋白表达。结论 小胶质细胞OGD/R损伤后,lncRNA LINC01089表达下调,促使小胶质细胞向M1型转化,诱导炎症反应,其机制可能与靶向负调控miR-449c-5p/STAT6信号轴有关。     

Paeonol alleviates neuropathic pain by modulating microglial M1 and M2 polarization via the RhoA/p38MAPK signaling pathway

Background

This study aimed to investigate the potential mechanism of paeonol in the treatment of neuropathic pain.

Methods

Relevant mechanisms were explored through microglial pseudotime analysis and the use of specific inhibitors in cell experiments. In animal experiments, 32 SD rats were randomly divided into the sham operation group, the chronic constrictive injury (CCI) group, the ibuprofen group, and the paeonol group. We performed behavioral testing, ELISA, PCR, Western blotting, immunohistochemistry, and immunofluorescence analysis.

Results

The pseudotime analysis of microglia found that RhoA, Rock1, and p38MAPK were highly expressed in activated microglia, and the expression patterns of these genes were consistent with the expression trends of the M1 markers CD32 and CD86. Paeonol decreased the levels of M1 markers (IL1β, iNOS, CD32, IL6) and increased the levels of M2 markers (IL10, CD206, ARG-1) in LPS-induced microglia. The expression of iNOS, IL1β, RhoA, and Rock1 was significantly increased in LPS-treated microglia, while paeonol decreased the expression of these proteins. Thermal hyperalgesia occurred after CCI surgery, and paeonol provided relief. In addition, paeonol decreased the levels of IL1β and IL8 and increased the levels of IL4 and TGF-β in the serum of CCI rats. Paeonol decreased expression levels of M1 markers and increased expression levels of M2 markers in the spinal cord. Paeonol decreased IBA-1, IL1β, RhoA, RhoA-GTP, COX2, Rock1, and p-p38MAPK levels in the spinal dorsal horn.

Conclusion

Paeonol relieves neuropathic pain by modulating microglial M1 and M2 phenotypes through the RhoA/p38 MAPK pathway.     

Lack of NG2 exacerbates neurological outcome and modulates glial responses after traumatic brain injury

Traumatic brain injury (TBI) is a major cause of death and disability. The underlying pathophysiology is characterized by secondary processes including neuronal death and gliosis. To elucidate the role of the NG2 proteoglycan we investigated the response of NG2‐knockout mice (NG2‐KO) to TBI. Seven days after TBI behavioral analysis, brain damage volumetry and assessment of blood brain barrier integrity demonstrated an exacerbated response of NG2‐KO compared to wild‐type (WT) mice. Reactive astrocytes and expression of the reactive astrocyte and neurotoxicity marker Lcn2 (Lipocalin‐2) were increased in the perilesional brain tissue of NG2‐KO mice. In addition, microglia/macrophages with activated morphology were increased in number and mRNA expression of the M2 marker Arg1 (Arginase 1) was enhanced in NG2‐KO mice. While TBI‐induced expression of pro‐inflammatory cytokine genes was unchanged between genotypes, PCR array screening revealed a marked TBI‐induced up‐regulation of the C‐X‐C motif chemokine 13 gene Cxcl13 in NG2‐KO mice. CXCL13, known to attract immune cells to the inflamed brain, was expressed by activated perilesional microglia/macrophages seven days after TBI. Thirty days after TBI, NG2‐KO mice still exhibited more pronounced neurological deficits than WT mice, up‐regulation of Cxcl13, enhanced CD45+ leukocyte infiltration and a relative increase of activated Iba‐1+/CD45+ microglia/macrophages. Our study demonstrates that lack of NG2 exacerbates the neurological outcome after TBI and associates with abnormal activation of astrocytes, microglia/macrophages and increased leukocyte recruitment to the injured brain. These findings suggest that NG2 may counteract neurological deficits and adverse glial responses in TBI. GLIA 2016;64:507–523     

动眼神经电生理学研究的动物模型建立

目的 建立适用于动眼神经损伤后神经再生及功能修复电生理研究的动物模型.方法 20只Beagle犬随机均分为单纯损伤组及损伤+刺激组.行右侧动眼神经海绵窦后段压榨损伤、颅内动眼神经刺激电极植入及右侧下斜肌记录电极植入.结果 实验手术均被所有实验犬耐受,下斜肌记录电极和颅内刺激电极成功植入,可用于记录运动单位电位(MUPs)及混合肌肉动作电位(CMAPs).结论 应用于动眼神经再生修复电生理研究的动物模型已经建立,此模型具有良好的可行性及可重复性.     

CX3CR1 deficiency induces an early protective inflammatory environment in ischemic mice

The studies on fractalkine and its unique receptor CX3CR1 in neurological disorders yielded contrasting results. We have explored the consequences of CX3CR1 deletion in ischemic (30′ MCAo) mice on: (1) brain infarct size; (2) microglia dynamism and morphology; (3) expression of markers of microglia/macrophages (M/M) activation and polarization. We observed smaller infarcts in cx3cr1^?/? (26.42 ± 7.41 mm³, mean ± sd) compared to wild type (36.29 ± 11.57) and cx3cr1^?/+ (34.49 ± 8.91) mice. We longitudinally analyzed microglia by in vivo two‐photon microscopy before, 1 and 24 h after transient ischemia. Microglia were stationary in both cx3cr1^?/? and cx3cr1^?/+ mice throughout the study. In cx3cr1^?/? mice, they displayed a significantly higher number of ramifications >10 μm at baseline and at 24 h after ischemia compared to cx3cr1^?/+ mice, indicating that CX3CR1 deficiency impaired the development of microglia hypertrophic/amoeboid morphology. At 24 h after ischemia, we performed post mortem quantitative immunohistochemistry for different M/M markers. In cx3cr1^?/? immunoreactivity for CD11b (M/M activation) and for CD68 (associated with phagocytosis) were decreased, while that for CD45^high (macrophage and leukocyte recruitment) was increased. In addition, immunoreactivity for Ym1 (M2 polarization) was enhanced, while that for iNOS (M1) was decreased. Our data show that in cx3cr1^?/? mice protection from ischemia at early time points after injury is associated with a protective inflammatory milieu, characterized by the promotion of M2 polarization markers.     

Reactive microgliosis engages distinct responses by microglial subpopulations after minor central nervous system injury

Microglia are bone marrow-derived cells that constitute a facultative macrophage population when activated by trauma or pathology in the CNS. Endogenous CNS-resident microglia as well as exogenous (immigrant) bone marrow-derived cells contribute to reactive microgliosis, raising fundamental questions about the cellular composition, kinetics, and functional characteristics of the reactive microglial cell population. Bone marrow chimeric mice reconstituted with green fluorescent protein-expressing (GFP(+)) donor bone marrow cells were subjected to entorhinal cortex lesion, resulting in selective axonal degeneration and a localized microglial reaction in the hippocampus. Flow cytometric evaluation of individually dissected hippocampi differentiated immigrant GFP(+) microglia from resident GFP(-) microglia (CD11b(+)CD45(dim)) and identified a subset of mainly resident CD11b(+) microglia that was induced to express CD34. The proportion of immigrant GFP(+) microglia (CD11b(+)CD45(dim)) increased signficantly by 3 and 5 days postlesion and reached a maximum of 13% by 7 days. These cells expressed lower CD11b levels than resident microglia, forming a distinct subpopulation on CD11b/CD45 profiles. The proportion of CD34(+)CD11b(+) microglia was significantly increased at 3 days postlesion but had normalized by 5 and 7 days, when the microglial reaction is known to be at its maximum. Our results show that distinct subpopulations of microglia respond to minor CNS injury. The heterogeneity in microglial response may have functional consequences for repair and possibly therapy.     

Microglia/macrophage polarization dynamics in white matter after traumatic brain injury

Mononuclear phagocytes are a population of multi-phenotypic cells and have dual roles in brain destruction/reconstruction. The phenotype-specific roles of microglia/macrophages in traumatic brain injury (TBI) are, however, poorly characterized. In the present study, TBI was induced in mice by a controlled cortical impact (CCI) and animals were killed at 1 to 14 days post injury. Real-time polymerase chain reaction (RT–PCR) and immunofluorescence staining for M1 and M2 markers were performed to characterize phenotypic changes of microglia/macrophages in both gray and white matter. We found that the number of M1-like phagocytes increased in cortex, striatum and corpus callosum (CC) during the first week and remained elevated until at least 14 days after TBI. In contrast, M2-like microglia/macrophages peaked at 5 days, but decreased rapidly thereafter. Notably, the severity of white matter injury (WMI), manifested by immunohistochemical staining for neurofilament SMI-32, was strongly correlated with the number of M1-like phagocytes. In vitro experiments using a conditioned medium transfer system confirmed that M1 microglia-conditioned media exacerbated oxygen glucose deprivation–induced oligodendrocyte death. Our results indicate that microglia/macrophages respond dynamically to TBI, experiencing a transient M2 phenotype followed by a shift to the M1 phenotype. The M1 phenotypic shift may propel WMI progression and represents a rational target for TBI treatment.     

白藜芦醇对蛛网膜下腔出血后神经炎症的作用和机制研究

目的 研究白藜芦醇对蛛网膜下腔出血（subarachnoid hemorrhage,SAH）后血肿区脑组织神经炎症的作用和机制。方法 将48只成年雄性SD大鼠随机分为三组：假手术组,SAH组和SAH+白藜芦醇处理组,每组16只。采用枕大池两次注血法构建SAH模型。SAH组和SAH+白藜芦醇组在构建模型前15 min和构建模型后5min分别给予生理盐水或白藜芦醇各一次。于构建模型后72小时利用NSS评分评估大鼠的神经功能,然后处死大鼠并获取保存脑组织。利用ELISA检测脑组织内促炎因子IL-1,IL-6、TNF-α和抗炎因子IL-4,IL-10、TGF-β的表达水平,利用RT-PCR检测小胶质细胞M1型特征性基因IL-1β、CD32和M2型特征性基因CD206、Arginase-1的表达水平。结果 与假手术组相比,SAH组大鼠神经功能下降（P<0.05）,脑组织中促炎因子IL-1,IL-6、TNF-α和抗炎因子IL-4,IL-10、TGF-β的表达水平升高（P<0.05）,小胶质细胞M1型特征性基因IL-1β、CD32和M2型特征性基因CD206、Arginase-1的表达水平也升高（P<0.05）。与生理盐水处理组相比,白藜芦醇处理组神经功能损伤程度下降（P<0.05）,脑组织中促炎因子IL-1,IL-6、TNF-α表达水平降低、抗炎因子IL-4,IL-10、TGF-β的表达水平升高（P<0.05）,小胶质细胞M1型特征性基因IL-1β、CD32表达水平降低、M2型特征性基因CD206、Arginase-1的表达水平升高（P<0.05）。结论 白藜芦醇通过促进SAH后小胶质细胞由M1型向M2型转换,从而减轻了神经炎症和神经功能损伤。