Background:Our previous study found that mouse embryonic neural stem cell(NSC)-derived exosomes(EXOs)regulated NSC differentiation via the miR-9/Hes1 axis.However,the effects of EXOs on brain microvascular endothelial...Background:Our previous study found that mouse embryonic neural stem cell(NSC)-derived exosomes(EXOs)regulated NSC differentiation via the miR-9/Hes1 axis.However,the effects of EXOs on brain microvascular endothelial cell(BMEC)dysfunction via the miR-9/Hes1 axis remain unknown.Therefore,the current study aimed to determine the effects of EXOs on BMEC proliferation,migration,and death via the miR-9/Hes1 axis.Methods:Immunofluorescence,quantitative real-time polymerase chain reaction,cell counting kit-8 assay,wound healing assay,calcein-acetoxymethyl/propidium iodide staining,and hematoxylin and eosin staining were used to determine the role and mechanism of EXOs on BMECs.Results:EXOs promoted BMEC proliferation and migration and reduced cell death under hypoxic conditions.The overexpression of miR-9 promoted BMEC prolifera-tion and migration and reduced cell death under hypoxic conditions.Moreover,miR-9 downregulation inhibited BMEC proliferation and migration and also promoted cell death.Hes1 silencing ameliorated the effect of amtagomiR-9 on BMEC proliferation and migration and cell death.Hyperemic structures were observed in the regions of the hippocampus and cortex in hypoxia-induced mice.Meanwhile,EXO treatment improved cerebrovascular alterations.Conclusion:NSC-derived EXOs can promote BMEC proliferation and migra-tion and reduce cell death via the miR-9/Hes1 axis under hypoxic conditions.Therefore,EXO therapeutic strategies could be considered for hypoxia-induced vascular injury.展开更多
Mesenchymal stem cell(MSC)-based therapy has emerged as a promising treatment for spinal cord injury(SCI),but improving the neurogenic potential of MSCs remains a challenge.Mixed lineage leukemia 1(MLL1),an H3K4me3 me...Mesenchymal stem cell(MSC)-based therapy has emerged as a promising treatment for spinal cord injury(SCI),but improving the neurogenic potential of MSCs remains a challenge.Mixed lineage leukemia 1(MLL1),an H3K4me3 methyltransferases,plays a critical role in regulating lineage-specific gene expression and influences neurogenesis.In this study,we investigated the role and mechanism of MLL1 in the neurogenesis of stem cells from apical papilla(SCAPs).We examined the expression of neural markers,and the nerve repair and regeneration ability of SCAPs using dynamic changes in neuron-like cells,immunofluorescence staining,and a SCI model.We employed a coimmunoprecipitation(Co-IP)assay,real-time RT-PCR,microarray analysis,and chromatin immunoprecipitation(ChIP)assay to investigate the molecular mechanism.The results showed that MLL1 knock-down increased the expression of neural markers,including neurogenic differentiation factor(NeuroD),neural cell adhesion molecule(NCAM),tyrosine hydroxylase(TH),βIII-tubulin and Nestin,and promoted neuron-like cell formation in SCAPs.In vivo,a transplantation experiment showed that depletion of MLL 1 in SCAPs can restore motor function in a rat SCI model.MLL1 can combine with WD repeat domain 5(WDR5)and WDR5 inhibit the expression of neural markers in SCAPs.MLL1 regulates Hairy and enhancer of split 1(HES1)expression by directly binds to HES1 promoters via regulating H3K4me3 methylation by interacting with WDR5.Additionally,HES1 enhances the expression of neural markers in SCAPs.Our findings demonstrate that MLL1 inhibits the neurogenic potential of SCAPs by interacting with WDR5 and repressing HES1.These results provide a potential therapeutic target for promoting the recovery of motor function in SCI patients.展开更多
目的观察丹龙醒脑方对脑缺血再灌注模型大鼠侧脑室室管膜下区(SVZ)神经干细胞(NSCs)增殖与Hes1、Hes5表达的影响,探讨其促进内源性NSCs增殖的作用机制。方法将80只雄性SD大鼠随机分为假手术组、模型组、依达拉奉组(依达组)、丹龙醒脑方...目的观察丹龙醒脑方对脑缺血再灌注模型大鼠侧脑室室管膜下区(SVZ)神经干细胞(NSCs)增殖与Hes1、Hes5表达的影响,探讨其促进内源性NSCs增殖的作用机制。方法将80只雄性SD大鼠随机分为假手术组、模型组、依达拉奉组(依达组)、丹龙醒脑方组(丹龙组)。采用线栓法制备局灶性脑缺血再灌注模型,再灌注7 d后取缺血侧SVZ脑组织。Brdu免疫荧光法检测SVZ NSCs增殖,RT-q PCR、Western blot分别检测Hes1、Hes5 m RNA和蛋白的表达。结果与假手术组比较,其余各组Brdu阳性细胞率增加,Hes1、Hes5 m RNA及蛋白表达明显升高(P<0.01);与模型组比较,依达组、丹龙组Brdu阳性细胞率明显增加,Hes1、Hes5 m RNA及蛋白表达水平明显增强(P<0.01);丹龙组Hes1 m RNA表达水平优于依达组(P<0.01),其余指标均无明显差异。结论丹龙醒脑方可促进脑缺血再灌注后大鼠SVZ NSCs增殖,并上调Hes1、Hes5表达水平,其机制可能与激活Notch信号通路有关。展开更多
基金Program of Natural Science Foundation of Shanghai,Grant/Award Number:21ZR1453800 and 22ZR1452400Program of National Natural Science Foundation of China,Grant/Award Number:82370057+3 种基金Fundamental Research Funds for the Central Universities,Grant/Award Number:22120220562Program of Shanghai Municipal Health Commission,Grant/Award Number:20204Y0384Program of National Key Research and Development Project of China,Grant/Award Number:2023YFC2509500。
文摘Background:Our previous study found that mouse embryonic neural stem cell(NSC)-derived exosomes(EXOs)regulated NSC differentiation via the miR-9/Hes1 axis.However,the effects of EXOs on brain microvascular endothelial cell(BMEC)dysfunction via the miR-9/Hes1 axis remain unknown.Therefore,the current study aimed to determine the effects of EXOs on BMEC proliferation,migration,and death via the miR-9/Hes1 axis.Methods:Immunofluorescence,quantitative real-time polymerase chain reaction,cell counting kit-8 assay,wound healing assay,calcein-acetoxymethyl/propidium iodide staining,and hematoxylin and eosin staining were used to determine the role and mechanism of EXOs on BMECs.Results:EXOs promoted BMEC proliferation and migration and reduced cell death under hypoxic conditions.The overexpression of miR-9 promoted BMEC prolifera-tion and migration and reduced cell death under hypoxic conditions.Moreover,miR-9 downregulation inhibited BMEC proliferation and migration and also promoted cell death.Hes1 silencing ameliorated the effect of amtagomiR-9 on BMEC proliferation and migration and cell death.Hyperemic structures were observed in the regions of the hippocampus and cortex in hypoxia-induced mice.Meanwhile,EXO treatment improved cerebrovascular alterations.Conclusion:NSC-derived EXOs can promote BMEC proliferation and migra-tion and reduce cell death via the miR-9/Hes1 axis under hypoxic conditions.Therefore,EXO therapeutic strategies could be considered for hypoxia-induced vascular injury.
基金the Beijing Natural Science Foundation(7222075 to Z.P.F.)National Natural Science Foundation of China(82130028 to Z.P.F.)+3 种基金the National Key Research and Development Program(2022YFA1104401 to Z.P.F.)the CAMS Innovation Fund for Medical Sciences(2019-I2M-5-031 to Z.P.F.)the Innovation Research Team Project of Beijing Stomatological Hospital,Capital Medical University(No.CXTD202204 to Z.P.F.)the Young Scientist Program of Beijing Stomatological Hospital,Capital Medical University(No.YSP202113 to C.Z.).
文摘Mesenchymal stem cell(MSC)-based therapy has emerged as a promising treatment for spinal cord injury(SCI),but improving the neurogenic potential of MSCs remains a challenge.Mixed lineage leukemia 1(MLL1),an H3K4me3 methyltransferases,plays a critical role in regulating lineage-specific gene expression and influences neurogenesis.In this study,we investigated the role and mechanism of MLL1 in the neurogenesis of stem cells from apical papilla(SCAPs).We examined the expression of neural markers,and the nerve repair and regeneration ability of SCAPs using dynamic changes in neuron-like cells,immunofluorescence staining,and a SCI model.We employed a coimmunoprecipitation(Co-IP)assay,real-time RT-PCR,microarray analysis,and chromatin immunoprecipitation(ChIP)assay to investigate the molecular mechanism.The results showed that MLL1 knock-down increased the expression of neural markers,including neurogenic differentiation factor(NeuroD),neural cell adhesion molecule(NCAM),tyrosine hydroxylase(TH),βIII-tubulin and Nestin,and promoted neuron-like cell formation in SCAPs.In vivo,a transplantation experiment showed that depletion of MLL 1 in SCAPs can restore motor function in a rat SCI model.MLL1 can combine with WD repeat domain 5(WDR5)and WDR5 inhibit the expression of neural markers in SCAPs.MLL1 regulates Hairy and enhancer of split 1(HES1)expression by directly binds to HES1 promoters via regulating H3K4me3 methylation by interacting with WDR5.Additionally,HES1 enhances the expression of neural markers in SCAPs.Our findings demonstrate that MLL1 inhibits the neurogenic potential of SCAPs by interacting with WDR5 and repressing HES1.These results provide a potential therapeutic target for promoting the recovery of motor function in SCI patients.
文摘目的观察丹龙醒脑方对脑缺血再灌注模型大鼠侧脑室室管膜下区(SVZ)神经干细胞(NSCs)增殖与Hes1、Hes5表达的影响,探讨其促进内源性NSCs增殖的作用机制。方法将80只雄性SD大鼠随机分为假手术组、模型组、依达拉奉组(依达组)、丹龙醒脑方组(丹龙组)。采用线栓法制备局灶性脑缺血再灌注模型,再灌注7 d后取缺血侧SVZ脑组织。Brdu免疫荧光法检测SVZ NSCs增殖,RT-q PCR、Western blot分别检测Hes1、Hes5 m RNA和蛋白的表达。结果与假手术组比较,其余各组Brdu阳性细胞率增加,Hes1、Hes5 m RNA及蛋白表达明显升高(P<0.01);与模型组比较,依达组、丹龙组Brdu阳性细胞率明显增加,Hes1、Hes5 m RNA及蛋白表达水平明显增强(P<0.01);丹龙组Hes1 m RNA表达水平优于依达组(P<0.01),其余指标均无明显差异。结论丹龙醒脑方可促进脑缺血再灌注后大鼠SVZ NSCs增殖,并上调Hes1、Hes5表达水平,其机制可能与激活Notch信号通路有关。
