目的探索TAR DNA结合蛋白43(transactive response DNA binding protein 43,TDP-43)在氧化应激诱导的小鼠神经元(neuro-2a,N2a)细胞损伤及小鼠痛觉敏化中的作用及机制。方法①为评估最佳诱导浓度,不同浓度的H_(2)O_(2)处理N2a细胞分为4...目的探索TAR DNA结合蛋白43(transactive response DNA binding protein 43,TDP-43)在氧化应激诱导的小鼠神经元(neuro-2a,N2a)细胞损伤及小鼠痛觉敏化中的作用及机制。方法①为评估最佳诱导浓度,不同浓度的H_(2)O_(2)处理N2a细胞分为4组:对照组、200μmol/L H_(2)O_(2)组、400μmol/L H_(2)O_(2)组和800μmol/L H_(2)O_(2)组。②为评估最佳诱导时间,400μmol/L H_(2)O_(2)处理N2a细胞分为4组:对照组、6 h H_(2)O_(2)组、12 h H_(2)O_(2)组和24 h H_(2)O_(2)组。③为验证线粒体DNA(mitochondria DNA,mtDNA)释放途径,使用环孢素(cyclosporin,CsA)抑制线粒体通透性转换孔(mitochondrial permeability transition pore,mPTP)分为3组:对照组、24 h H_(2)O_(2)组和24 h H_(2)O_(2)+CsA组。④为验证TDP-43介导的细胞损伤机制,siRNA抑制TDP-43后分为3组:对照组、24 h H_(2)O_(2)组、24 h H_(2)O_(2)+siTDP-43组。⑤采用CCK-8检测细胞活性,EdU检测细胞增殖,Western blot检测TDP-43、神经元标志物(neuronal nuclei,NeuN)、环状GMP-AMP合酶(cylic GMP-AMP synthase,cGAS)和干扰素基因刺激因子(stimulator of interferon,STING)表达,qPCR检测mtDNA,免疫染色观察细胞内TDP-43表达变化,Calcein AM染色评估mPTP开放。⑥为验证TDP-43在神经病理性疼痛(neuropathic pain,NP)中的作用,将24只6~8周健康SPF级雄性C57BL/6J小鼠(体质量25~30 g)使用随机数字表法分为3组:对照组、慢性压迫性损伤(chronic constriction injury,CCI)组、CCI+siTDP-43组,术前1 d和术后7、14、21 d进行鞘内注射siTDP-43;术前1 d和术后1、3、5、7、14、21 d通过von Frey纤维丝和热辐射法测定小鼠机械痛阈值和热痛阈值,免疫荧光检测术后21 d腰段(L5-L6)脊髓背角中TDP-43与NeuN的变化。结果氧化应激刺激诱导N2a中TDP-43蛋白表达增加,刺激mtDNA通过mPTP释放,上调cGAS、STING的表达,影响N2a的细胞活性(P<0.05);CsA抑制mPTP通道的开放并减少mtDNA释放(P<0.05);下调TDP-43的表达后可显著降低mtDNA的释放,抑制cGAS和STING的表达,并恢复N2a细胞的增殖能力(P<0.05)。CCI术后5 d,小鼠机械痛阈值和热痛阈值出现明显下降并持续至21 d(P<0.05);CCI小鼠术后21 d脊髓背角神经元中TDP-43表达增加(P<0.05);鞘内注射siRNA抑制TDP-43后,可提高CCI小鼠的机械痛阈值和热痛阈值(P<0.05)。结论氧化应激诱导神经元细胞TDP-43蛋白增加,刺激mtDNA通过mPTP释放到细胞质,激活cGAS/STING通路,导致神经元损伤并加重CCI小鼠痛觉敏化。展开更多
The West Junggar of the western Central Asian Orogenic Belt is one of the typical regions in the term of ocean subduction, contraction and continental growth in the Late Paleozoic. However, it is still controversial o...The West Junggar of the western Central Asian Orogenic Belt is one of the typical regions in the term of ocean subduction, contraction and continental growth in the Late Paleozoic. However, it is still controversial on the exact time of ocean-continent transition so far. This study investigates rhyolites with columnar joint in the West Junggar for the first time.Based on zircon U-Pb dating, we determined that the ages of the newly-discovered rhyolites are between 303.6 and 294.5 Ma, belonging to Late Carboniferous–Early Permian, which is the oldest rhyolite with columnar joint preserved in the world at present. Geochemical results show that the characteristics of the major element compositions include a high content of SiO_2(75.78–79.20 wt%) and a moderate content of Al_2O_3(12.21–13.19 wt%). The total alkali content(K_2O +Na_2O) is 6.14–8.05 wt%, among which K_2O is 2.09–4.72 wt% and the rate of K_2O/Na_2O is 0.38–3.05. Over-based minerals such as Ne, Lc, and Ac do not appear. The contents of TiO_2(0.09–0.24 wt%), CaO(0.15–0.99 wt%) and MgO(0.06–0.18 wt%) are low. A/CNK=0.91–1.68, A/NK=1.06–1.76, and as such, these are associated with the quasi-aluminum-weak peraluminous high potassium calc-alkaline and some calc-alkaline magma series. These rhyolites show a significant negative Eu anomaly with relative enrichment of LREE and LILE(Rb, Ba, Th, U, K) and depletion of Sr, HREE and HFSE(Nb, Ta, Ti, P). These rhyolites also have the characteristics of an A2-type granite, similar to the Miaoergou batholith,which indicates they both were affected by post-orogenic extension. Combining petrological, zircon U-Pb dating and geochemical characteristics of the rhyolites, we conclude that the specific time of ocean-continent transition of the West Junggar is the Late Carboniferous–Early Permian.展开更多
文摘目的探索TAR DNA结合蛋白43(transactive response DNA binding protein 43,TDP-43)在氧化应激诱导的小鼠神经元(neuro-2a,N2a)细胞损伤及小鼠痛觉敏化中的作用及机制。方法①为评估最佳诱导浓度,不同浓度的H_(2)O_(2)处理N2a细胞分为4组:对照组、200μmol/L H_(2)O_(2)组、400μmol/L H_(2)O_(2)组和800μmol/L H_(2)O_(2)组。②为评估最佳诱导时间,400μmol/L H_(2)O_(2)处理N2a细胞分为4组:对照组、6 h H_(2)O_(2)组、12 h H_(2)O_(2)组和24 h H_(2)O_(2)组。③为验证线粒体DNA(mitochondria DNA,mtDNA)释放途径,使用环孢素(cyclosporin,CsA)抑制线粒体通透性转换孔(mitochondrial permeability transition pore,mPTP)分为3组:对照组、24 h H_(2)O_(2)组和24 h H_(2)O_(2)+CsA组。④为验证TDP-43介导的细胞损伤机制,siRNA抑制TDP-43后分为3组:对照组、24 h H_(2)O_(2)组、24 h H_(2)O_(2)+siTDP-43组。⑤采用CCK-8检测细胞活性,EdU检测细胞增殖,Western blot检测TDP-43、神经元标志物(neuronal nuclei,NeuN)、环状GMP-AMP合酶(cylic GMP-AMP synthase,cGAS)和干扰素基因刺激因子(stimulator of interferon,STING)表达,qPCR检测mtDNA,免疫染色观察细胞内TDP-43表达变化,Calcein AM染色评估mPTP开放。⑥为验证TDP-43在神经病理性疼痛(neuropathic pain,NP)中的作用,将24只6~8周健康SPF级雄性C57BL/6J小鼠(体质量25~30 g)使用随机数字表法分为3组:对照组、慢性压迫性损伤(chronic constriction injury,CCI)组、CCI+siTDP-43组,术前1 d和术后7、14、21 d进行鞘内注射siTDP-43;术前1 d和术后1、3、5、7、14、21 d通过von Frey纤维丝和热辐射法测定小鼠机械痛阈值和热痛阈值,免疫荧光检测术后21 d腰段(L5-L6)脊髓背角中TDP-43与NeuN的变化。结果氧化应激刺激诱导N2a中TDP-43蛋白表达增加,刺激mtDNA通过mPTP释放,上调cGAS、STING的表达,影响N2a的细胞活性(P<0.05);CsA抑制mPTP通道的开放并减少mtDNA释放(P<0.05);下调TDP-43的表达后可显著降低mtDNA的释放,抑制cGAS和STING的表达,并恢复N2a细胞的增殖能力(P<0.05)。CCI术后5 d,小鼠机械痛阈值和热痛阈值出现明显下降并持续至21 d(P<0.05);CCI小鼠术后21 d脊髓背角神经元中TDP-43表达增加(P<0.05);鞘内注射siRNA抑制TDP-43后,可提高CCI小鼠的机械痛阈值和热痛阈值(P<0.05)。结论氧化应激诱导神经元细胞TDP-43蛋白增加,刺激mtDNA通过mPTP释放到细胞质,激活cGAS/STING通路,导致神经元损伤并加重CCI小鼠痛觉敏化。
基金supported by the China Geological Survey (grant numbers DD20160083 and DD20160344-05)the National Key Research and Development Program of China (grant numbers 2018YFC0603701)Fundamental Research Funds for Central Public Welfare Research Institutes (grant numbers CAGS-YWF201706)
文摘The West Junggar of the western Central Asian Orogenic Belt is one of the typical regions in the term of ocean subduction, contraction and continental growth in the Late Paleozoic. However, it is still controversial on the exact time of ocean-continent transition so far. This study investigates rhyolites with columnar joint in the West Junggar for the first time.Based on zircon U-Pb dating, we determined that the ages of the newly-discovered rhyolites are between 303.6 and 294.5 Ma, belonging to Late Carboniferous–Early Permian, which is the oldest rhyolite with columnar joint preserved in the world at present. Geochemical results show that the characteristics of the major element compositions include a high content of SiO_2(75.78–79.20 wt%) and a moderate content of Al_2O_3(12.21–13.19 wt%). The total alkali content(K_2O +Na_2O) is 6.14–8.05 wt%, among which K_2O is 2.09–4.72 wt% and the rate of K_2O/Na_2O is 0.38–3.05. Over-based minerals such as Ne, Lc, and Ac do not appear. The contents of TiO_2(0.09–0.24 wt%), CaO(0.15–0.99 wt%) and MgO(0.06–0.18 wt%) are low. A/CNK=0.91–1.68, A/NK=1.06–1.76, and as such, these are associated with the quasi-aluminum-weak peraluminous high potassium calc-alkaline and some calc-alkaline magma series. These rhyolites show a significant negative Eu anomaly with relative enrichment of LREE and LILE(Rb, Ba, Th, U, K) and depletion of Sr, HREE and HFSE(Nb, Ta, Ti, P). These rhyolites also have the characteristics of an A2-type granite, similar to the Miaoergou batholith,which indicates they both were affected by post-orogenic extension. Combining petrological, zircon U-Pb dating and geochemical characteristics of the rhyolites, we conclude that the specific time of ocean-continent transition of the West Junggar is the Late Carboniferous–Early Permian.
