Blood exosomes,which are extracellular vesicles secreted by living cells into the circulating blood,are regarded as a relatively noninvasive novel tool for monitoring brain physiology and disease states.An increasing ...Blood exosomes,which are extracellular vesicles secreted by living cells into the circulating blood,are regarded as a relatively noninvasive novel tool for monitoring brain physiology and disease states.An increasing number of blood cargo-loaded exosomes are emerging as potential biomarkers for preclinical and clinical Alzheimer's disease.Therefo re,we conducted a meta-analysis and systematic review of molecular biomarkers derived from blood exosomes to comprehensively analyze their diagnostic performance in preclinical Alzheimer's disease,mild cognitive impairment,and Alzheimer's disease.We performed a literature search in PubMed,Web of Science,Embase,and Cochrane Library from their inception to August 15,2020.The research subjects mainly included Alzheimer's disease,mild cognitive impairment,and preclinical Alzheimer's disease.We identified 34 observational studies,of which 15 were included in the quantitative analysis(Newcastle-Ottawa Scale score 5.87 points)and 19 were used in the qualitative analysis.The meta-analysis results showed that core biomarkers including Aβ_(1-42),P-T181-tau,P-S396-tau,and T-tau were increased in blood neuro nderived exosomes of preclinical Alzheimer's disease,mild cognitive impairment,and Alzheimer's disease patients.M olecules related to additional risk facto rs that are involved in neuroinflammation(C1q),metabolism disorder(P-S312-IRS-1),neurotrophic deficiency(HGF),vascular injury(VEGF-D),and autophagy-lysosomal system dysfunction(cathepsin D)were also increased.At the gene level,the differential expression of transc ription-related factors(REST)and microRNAs(miR-132)also affects RNA splicing,transport,and translation.These pathological changes contribute to neural loss and synaptic dysfunction.The data confirm that the above-mentioned core molecules and additional ris k-related factors in blood exosomes can serve as candidate biomarkers for preclinical and clinical Alzheimer's disease.These findings support further development of exosome biomarkers for a clinical blood test for Alzheimer's disease.This meta-analysis was registered at the International Prospective Register of Systematic Reviews(Registration No.CRD4200173498,28/04/2020).展开更多
创伤后的神经胶质增生导致硫酸软骨素蛋白聚糖(CSPG)的显著表达,从而抑制轴突生长和再生。甲基强地松龙(MP),一种合成的糖皮质激素,在急性脊髓损伤(SCI)的治疗中有神经保护作用和抗炎效应。但是,MP对于CSPG在活性胶质细胞中的表达的作...创伤后的神经胶质增生导致硫酸软骨素蛋白聚糖(CSPG)的显著表达,从而抑制轴突生长和再生。甲基强地松龙(MP),一种合成的糖皮质激素,在急性脊髓损伤(SCI)的治疗中有神经保护作用和抗炎效应。但是,MP对于CSPG在活性胶质细胞中的表达的作用尚不清楚。本文用a-氨基-3-羟基-5-甲基-4-异恶唑丙酸酯(AM-PA)诱导星形胶质细胞再活化,用环噻嗪模拟SCI的兴奋性中毒刺激。AMPA治疗后,星形胶质细胞再活化的标志物-胶质纤维酸性蛋白(GFAP)、CSPG神经聚糖和磷酸盐的表达都显著上调。AMPA治疗星形胶质细胞的条件培养液强烈抑制大鼠背根神经节中神经元的轴突生长,但这种作用能被MP的预处理所逆转。此外,MP下调成年SCI大鼠中GFAP和CSPG的表达,对抗RU486的糖皮质激素受体(GR)和GR si RNA能逆转MP对GFAP和神经聚糖表达的抑制作用。这些结果提示,MP能在兴奋性中毒损伤后通过GR介导的星形胶质细胞再活化下调和GSPG表达抑制来改善神经修复,促进轴突生长。展开更多
Objective Studies have shown that electroacupuncture(EA)can alleviate cognitive impairments from Alzheimer’s disease(AD)by regulating the expression of adenosine monophosphate-activated protein kinase(AMPK),but the s...Objective Studies have shown that electroacupuncture(EA)can alleviate cognitive impairments from Alzheimer’s disease(AD)by regulating the expression of adenosine monophosphate-activated protein kinase(AMPK),but the specific mechanism involved remains to be elucidated.Therefore,this study explores the potential mechanism by which EA improves cognitive function from the perspective of mitochondrial dynamics.Methods The four-month-old transgenic mice with amyloid precursor protein(APP)/presenilin 1(PS1)and AMPKα1-subunit conditional knockout(AMPKα1-cKO)were used for experiments.To evaluate the effects of EA treatment on cognitive function,the T-maze and Morris water maze were used.In addition,chemical exchange saturation transfer,thioflavin staining,transmission electron microscopy,mitochondrial membrane potential,and Western blotting were used to examine the potential mechanisms underlying the effects of EA on APP/PS1 mice.Results Both APP/PS1 mice and AMPKα1-cKO mice exhibited dysfunction in mitochondrial dynamics accompanied by learning and memory impairment.Inactivation of the AMPK/peroxisome proliferator-activated receptor-γcoactivator-1α(PGC-1α)pathway increased pathological amyloid-β(Aβ)deposition and aggravated the dysfunction in mitochondrial dynamics.In addition,EA rescued learning and memory deficits in APP/PS1 mice by activating the AMPK/PGC-1αpathway,specifically by reducing pathological Aβdeposition,normalizing energy metabolism,protecting the structure and function of mitochondria,increasing the levels of mitochondrial fusion proteins,and downregulating the expression of fission proteins.However,the therapeutic effect of EA on cognition in APP/PS1 mice was hindered by AMPKα1 knockout.Conclusion The regulation of hippocampal mitochondrial dynamics and reduction in Aβdeposition via the AMPK/PGC-1αpathway are critical for the ability of EA to ameliorate cognitive impairment in APP/PS1 mice.展开更多
The long chain branching(LCB)polyglycolide(PGA)was successfully prepared by the successive reactions of the terminal hydroxyl groups of PGA with triglycidyl isocyanurate(TGIC)and pyromellitic dianhydride(PMDA).The inf...The long chain branching(LCB)polyglycolide(PGA)was successfully prepared by the successive reactions of the terminal hydroxyl groups of PGA with triglycidyl isocyanurate(TGIC)and pyromellitic dianhydride(PMDA).The influence of LCB produced by functional group reaction on rheological and crystallization behavior was studied and discussed through linear rheology,uniaxial elongation and DSC(differential scanning calorimetry).The much higher viscosity and the more notable strain hardening behavior of modified PGA indicates the LCB with high degree of entanglements are created.The melt strength of PGA is finally improved greatly and can make su re that the supercritical CO_(2)foaming can be carried out successfully.展开更多
基金the National Natural Science Foundation of China(Key Project),No.82030123(to LDC)the Science and Technology Platform Construction Project of Fujian Science and Technology Department,No.2018Y2002(to LDC)。
文摘Blood exosomes,which are extracellular vesicles secreted by living cells into the circulating blood,are regarded as a relatively noninvasive novel tool for monitoring brain physiology and disease states.An increasing number of blood cargo-loaded exosomes are emerging as potential biomarkers for preclinical and clinical Alzheimer's disease.Therefo re,we conducted a meta-analysis and systematic review of molecular biomarkers derived from blood exosomes to comprehensively analyze their diagnostic performance in preclinical Alzheimer's disease,mild cognitive impairment,and Alzheimer's disease.We performed a literature search in PubMed,Web of Science,Embase,and Cochrane Library from their inception to August 15,2020.The research subjects mainly included Alzheimer's disease,mild cognitive impairment,and preclinical Alzheimer's disease.We identified 34 observational studies,of which 15 were included in the quantitative analysis(Newcastle-Ottawa Scale score 5.87 points)and 19 were used in the qualitative analysis.The meta-analysis results showed that core biomarkers including Aβ_(1-42),P-T181-tau,P-S396-tau,and T-tau were increased in blood neuro nderived exosomes of preclinical Alzheimer's disease,mild cognitive impairment,and Alzheimer's disease patients.M olecules related to additional risk facto rs that are involved in neuroinflammation(C1q),metabolism disorder(P-S312-IRS-1),neurotrophic deficiency(HGF),vascular injury(VEGF-D),and autophagy-lysosomal system dysfunction(cathepsin D)were also increased.At the gene level,the differential expression of transc ription-related factors(REST)and microRNAs(miR-132)also affects RNA splicing,transport,and translation.These pathological changes contribute to neural loss and synaptic dysfunction.The data confirm that the above-mentioned core molecules and additional ris k-related factors in blood exosomes can serve as candidate biomarkers for preclinical and clinical Alzheimer's disease.These findings support further development of exosome biomarkers for a clinical blood test for Alzheimer's disease.This meta-analysis was registered at the International Prospective Register of Systematic Reviews(Registration No.CRD4200173498,28/04/2020).
文摘创伤后的神经胶质增生导致硫酸软骨素蛋白聚糖(CSPG)的显著表达,从而抑制轴突生长和再生。甲基强地松龙(MP),一种合成的糖皮质激素,在急性脊髓损伤(SCI)的治疗中有神经保护作用和抗炎效应。但是,MP对于CSPG在活性胶质细胞中的表达的作用尚不清楚。本文用a-氨基-3-羟基-5-甲基-4-异恶唑丙酸酯(AM-PA)诱导星形胶质细胞再活化,用环噻嗪模拟SCI的兴奋性中毒刺激。AMPA治疗后,星形胶质细胞再活化的标志物-胶质纤维酸性蛋白(GFAP)、CSPG神经聚糖和磷酸盐的表达都显著上调。AMPA治疗星形胶质细胞的条件培养液强烈抑制大鼠背根神经节中神经元的轴突生长,但这种作用能被MP的预处理所逆转。此外,MP下调成年SCI大鼠中GFAP和CSPG的表达,对抗RU486的糖皮质激素受体(GR)和GR si RNA能逆转MP对GFAP和神经聚糖表达的抑制作用。这些结果提示,MP能在兴奋性中毒损伤后通过GR介导的星形胶质细胞再活化下调和GSPG表达抑制来改善神经修复,促进轴突生长。
基金supported by the Fujian Provincial Outstanding Natural Science Foundation(No.2021J06028)the key project at the central government level:the ability establishment of sustainable use for valuable Chinese Medicine Resources(No.2060302).
文摘Objective Studies have shown that electroacupuncture(EA)can alleviate cognitive impairments from Alzheimer’s disease(AD)by regulating the expression of adenosine monophosphate-activated protein kinase(AMPK),but the specific mechanism involved remains to be elucidated.Therefore,this study explores the potential mechanism by which EA improves cognitive function from the perspective of mitochondrial dynamics.Methods The four-month-old transgenic mice with amyloid precursor protein(APP)/presenilin 1(PS1)and AMPKα1-subunit conditional knockout(AMPKα1-cKO)were used for experiments.To evaluate the effects of EA treatment on cognitive function,the T-maze and Morris water maze were used.In addition,chemical exchange saturation transfer,thioflavin staining,transmission electron microscopy,mitochondrial membrane potential,and Western blotting were used to examine the potential mechanisms underlying the effects of EA on APP/PS1 mice.Results Both APP/PS1 mice and AMPKα1-cKO mice exhibited dysfunction in mitochondrial dynamics accompanied by learning and memory impairment.Inactivation of the AMPK/peroxisome proliferator-activated receptor-γcoactivator-1α(PGC-1α)pathway increased pathological amyloid-β(Aβ)deposition and aggravated the dysfunction in mitochondrial dynamics.In addition,EA rescued learning and memory deficits in APP/PS1 mice by activating the AMPK/PGC-1αpathway,specifically by reducing pathological Aβdeposition,normalizing energy metabolism,protecting the structure and function of mitochondria,increasing the levels of mitochondrial fusion proteins,and downregulating the expression of fission proteins.However,the therapeutic effect of EA on cognition in APP/PS1 mice was hindered by AMPKα1 knockout.Conclusion The regulation of hippocampal mitochondrial dynamics and reduction in Aβdeposition via the AMPK/PGC-1αpathway are critical for the ability of EA to ameliorate cognitive impairment in APP/PS1 mice.
文摘The long chain branching(LCB)polyglycolide(PGA)was successfully prepared by the successive reactions of the terminal hydroxyl groups of PGA with triglycidyl isocyanurate(TGIC)and pyromellitic dianhydride(PMDA).The influence of LCB produced by functional group reaction on rheological and crystallization behavior was studied and discussed through linear rheology,uniaxial elongation and DSC(differential scanning calorimetry).The much higher viscosity and the more notable strain hardening behavior of modified PGA indicates the LCB with high degree of entanglements are created.The melt strength of PGA is finally improved greatly and can make su re that the supercritical CO_(2)foaming can be carried out successfully.
