Previous studies have shown that sirtuin 1(SIRT1) reduces the production of neuronal amyloid beta(Aβ) and inhibits the inflammatory response of glial cells, thereby generating a neuroprotective effect against Aβ neu...Previous studies have shown that sirtuin 1(SIRT1) reduces the production of neuronal amyloid beta(Aβ) and inhibits the inflammatory response of glial cells, thereby generating a neuroprotective effect against Aβ neurotoxicity in animal models of Alzheimer's disease. However, the protective effect of SIRT1 on astrocytes is still under investigation. This study established a time point model for the clearance of Aβ in primary astrocytes. Results showed that 12 hours of culture was sufficient for endocytosis of oligomeric Aβ, and 36 hours sufficient for effective degradation. Immunofluorescence demonstrated that Aβ degradation in primary astrocytes relies on lysosome function. Enzymatic agonists or SIRT1 inhibitors were used to stimulate cells over a concentration gradient. Aβ was co-cultured for 36 hours in medium. Western blot assay results under different conditions revealed that SIRT1 relies on its deacetylase activity to promote intracellular Aβ degradation. The experiment further screened SIRT1 using quantitative proteomics to investigate downstream, differentially expressed proteins in the Aβ degradation pathway and selected the ones related to enzyme activity of SIRT1. Most of the differentially expressed proteins detected are close to the primary astrocyte lysosomal pathway. Immunofluorescence staining demonstrated that SIRT1 relies on its deacetylase activity to upregulate lysosome number in primary astrocytes. Taken together, these findings confirm that SIRT1 relies on its deacetylase activity to upregulate lysosome number, thereby facilitating oligomeric Aβ degradation in primary astrocytes.展开更多
5-Bromo-2′-deoxyuridine(BrdU)is a halogenated pyrimidine that can be incorporated into newly synthesized DNA during the S phase of the cell cycle.BrdU is widely used in fate-mapping studies of embryonic and adult neu...5-Bromo-2′-deoxyuridine(BrdU)is a halogenated pyrimidine that can be incorporated into newly synthesized DNA during the S phase of the cell cycle.BrdU is widely used in fate-mapping studies of embryonic and adult neurogenesis to identify newborn neurons,however side effects on neural stem cells and their progeny have been reported.In vivo astrocyte-to-neuron(AtN)conversion is a new approach for generating newborn neurons by directly converting endogenous astrocytes into neurons.The BrdU-labeling strategy has been used to trace astrocyte-converted neurons,but whether BrdU has any effect on the AtN conversion is unknown.Here,while conducting a NeuroD1-mediated AtN conversion study using BrdU to label dividing reactive astrocytes following ischemic injury,we accidentally discovered that BrdU inhibited AtN conversion.We initially found a gradual reduction in BrdU-labeled astrocytes during NeuroD1-mediated AtN conversion in the mouse cortex.Although most NeuroD1-infected astrocytes were converted into neurons,the number of BrdU-labeled neurons was surprisingly low.To exclude the possibility that this BrdU inhibition was caused by the ischemic injury,we conducted an in vitro AtN conversion study by overexpressing NeuroD1 in cultured cortical astrocytes in the presence or absence of BrdU.Surprisingly,we also found a significantly lower conversion rate and a smaller number of converted neurons in the BrdU-treated group compared with the untreated group.These results revealed an unexpected inhibitory effect of BrdU on AtN conversion,suggesting more caution is needed when using BrdU in AtN conversion studies and in data interpretation.展开更多
Objective:To investigate the role of baicalein in phenotypic transformation of vascularsmooth muscle cells induced by high glucose.Methods:Rat vascular smooth muscle cellexperiments were divided into control group,bai...Objective:To investigate the role of baicalein in phenotypic transformation of vascularsmooth muscle cells induced by high glucose.Methods:Rat vascular smooth muscle cellexperiments were divided into control group,baicalein group,high glucose group,highglucose plus baicalein group,real time quantitative PCR were used for mRNA analysis of-SMA,SM22-αnd OPN,Western blot were used for protein analysis of α-SMA,SM22-αand OPN.Results:Comparing the high glucose group and the high glucose plus baicaleingroup,the level of α-SMA mRNA in high glucose group was 0.419±0.090,the level ofα-SMA mRNA in high glucose plus baicalein group was 0.699±0.079,the latter was 66.8%higher than the former.The level of α-SMA protein in high glucose group was 0.213±0.034,the level of α-SMA protein in high glucose plus baicalein group was 0.393±0.062,the latterwas 84.5%higher than the former.Baicalein could significantly inhibit the down-regulationof α-SMA gene expression induced by high glucose(P<0.05).Comparing the high glucosegroup and the high glucose plus baicalein group,the level of SM22-mRNA in high glucosegroup was 0.369±0.063,the level of SM22-α mRNA in high glucose plus baicalein groupwas 0.583±0.049,the latter was 58.0%higher than the former.The level of SM22-α proteinin high glucose group was 0.343±0.047,the level of SM22-protein in high glucose plusbaicalein group was 0.486±0.051,the latter was 41.7%higher than the former.Baicaleincould significantly inhibit the down-regulation of SM22-α gene expression induced by highglucose(P<0.05).Comparing the high glucose group and the high glucose plus baicaleingroup,the level of OPN mRNA in high glucose group was 2.023±0.281,the level of OPNmRNA in high glucose plus baicalein group was 1.511±0.091,the latter was 25.3%lowerthan the former.The level of OPN protein in high glucose group was 1.063±0.132,the levelof OPN protein in high glucose plus baicalein group was 0.761±0.089,the latter was 28.4%lower than the former.Baicalein could significantly inhibit the up-regulation of OPN geneexpression induced by high glucose(P<0.05).Conclusion:Baicalein can significantly inhibitthe high glucose-induced phenotypic transformation of vascular smooth muscle cells fromcontractile phenotype to synthetic phenotype.展开更多
OBJECTIVE To assess the feasibility and safety of the minimalistic approach to left atrial appendage occlusion(LAAO) guided by cardiac computed tomography angiography(CCTA).METHODS Ninety consecutive patients who unde...OBJECTIVE To assess the feasibility and safety of the minimalistic approach to left atrial appendage occlusion(LAAO) guided by cardiac computed tomography angiography(CCTA).METHODS Ninety consecutive patients who underwent LAAO, with or without CCTA-guided, were matched(1:2). Each step of the LAAO procedure in the computed tomography(CT) guidance group(CT group) was directed by preprocedural CT planning. In the control group, LAAO was performed using the standard method. All patients were followed up for 12 months, and device surveillance was conducted using CCTA.RESULTS A total of 90 patients were included in the analysis, with 30 patients in the CT group and 60 matched patients in the control group. All patients were successfully implanted with Watchman devices. The mean ages for the CT group and the control group were 70.0 ± 9.4 years and 68.4 ± 11.9 years(P = 0.52), respectively. The procedure duration(45.6 ± 10.7 min vs. 58.8 ± 13.0 min,P < 0.001) and hospital stay(7.5 ± 2.4 day vs. 9.6 ± 2.8 day, P = 0.001) in the CT group was significantly shorter compared to the control group. However, the total radiation dose was higher in the CT group compared to the control group(904.9 ± 348.0 m Gy vs.711.9 ± 211.2 m Gy, P = 0.002). There were no significant differences in periprocedural pericardial effusion(3.3% vs. 6.3%, P = 0.8) between the two groups. The rate of postprocedural adverse events(13.3% vs. 18.3%, P = 0.55) were comparable between both groups at 12 months follow-up.CONCLUSIONS CCTA is capable of detailed LAAO procedure planning. Minimalistic LAAO with preprocedural CCTA planning was feasible and safe, with shortened procedure time and acceptable increased radiation and contras consumption. For patients with contraindications to general anesthesia and/or transesophageal echocardiography, this promising method may be an alternative to conventional LAAO.展开更多
Dementia is increasing dramatically and imposes a huge burden on society. To date, there is a lack of data on the health status of patients with dementia in China. In an attempt to investigate the comorbidity burden o...Dementia is increasing dramatically and imposes a huge burden on society. To date, there is a lack of data on the health status of patients with dementia in China. In an attempt to investigate the comorbidity burden of dementia patients in China at the national level, we enrolled 2,938 patients with Alzheimer's disease(AD), vascular dementia(Va D), or other types of dementia, who were admitted to tertiary hospitals in seven regions of China from January2003 to December 2012. The Charlson Comorbidity Index(CCI) was used to evaluate the comorbidity burden of the patients with dementia. Among these patients, 53.4% had AD, 26.3% had Va D, and 20.3% had other types of dementia. The CCI was 3.0 ± 1.9 for all patients,3.4 ± 1.8 for those with Va D, and 3.0 ± 2.1 for those with AD. The CCI increased with age in all patients, andthe length of hospital stay and daily expenses rose with age and CCI. Males had a higher CCI and a longer stay than females. Moreover, patients admitted in the last 5 years of the study had a higher CCI than those admitted in the first 5 years. We found that the comorbidity burden of patients with dementia is heavy. These findings provide a better understanding of the overall health status of dementia patients, and help to increase the awareness of clinicians and policy-makers to improve medical care for patients.展开更多
基金supported by the National Natural Science Foundation of China,No.31670832,31470807,31270872a grant from the National Key Research and Development Program of China,No.2016YFA0500301a grant from the State Key Laboratory of Protein and Plant Gene Research,College of Life Sciences,Peking University,China
文摘Previous studies have shown that sirtuin 1(SIRT1) reduces the production of neuronal amyloid beta(Aβ) and inhibits the inflammatory response of glial cells, thereby generating a neuroprotective effect against Aβ neurotoxicity in animal models of Alzheimer's disease. However, the protective effect of SIRT1 on astrocytes is still under investigation. This study established a time point model for the clearance of Aβ in primary astrocytes. Results showed that 12 hours of culture was sufficient for endocytosis of oligomeric Aβ, and 36 hours sufficient for effective degradation. Immunofluorescence demonstrated that Aβ degradation in primary astrocytes relies on lysosome function. Enzymatic agonists or SIRT1 inhibitors were used to stimulate cells over a concentration gradient. Aβ was co-cultured for 36 hours in medium. Western blot assay results under different conditions revealed that SIRT1 relies on its deacetylase activity to promote intracellular Aβ degradation. The experiment further screened SIRT1 using quantitative proteomics to investigate downstream, differentially expressed proteins in the Aβ degradation pathway and selected the ones related to enzyme activity of SIRT1. Most of the differentially expressed proteins detected are close to the primary astrocyte lysosomal pathway. Immunofluorescence staining demonstrated that SIRT1 relies on its deacetylase activity to upregulate lysosome number in primary astrocytes. Taken together, these findings confirm that SIRT1 relies on its deacetylase activity to upregulate lysosome number, thereby facilitating oligomeric Aβ degradation in primary astrocytes.
基金supported by the Natural Science Foundation of Guangdong Province of China,Nos.2021A1515011237(to WL),2020A1515010854(to QSW)the National Natural Science Foundation of China,Nos.U1801681(to GC),31701291(to WL)the Guangdong Province Science and Technology Planning Project of China,No.2018B030332001(to GC)。
文摘5-Bromo-2′-deoxyuridine(BrdU)is a halogenated pyrimidine that can be incorporated into newly synthesized DNA during the S phase of the cell cycle.BrdU is widely used in fate-mapping studies of embryonic and adult neurogenesis to identify newborn neurons,however side effects on neural stem cells and their progeny have been reported.In vivo astrocyte-to-neuron(AtN)conversion is a new approach for generating newborn neurons by directly converting endogenous astrocytes into neurons.The BrdU-labeling strategy has been used to trace astrocyte-converted neurons,but whether BrdU has any effect on the AtN conversion is unknown.Here,while conducting a NeuroD1-mediated AtN conversion study using BrdU to label dividing reactive astrocytes following ischemic injury,we accidentally discovered that BrdU inhibited AtN conversion.We initially found a gradual reduction in BrdU-labeled astrocytes during NeuroD1-mediated AtN conversion in the mouse cortex.Although most NeuroD1-infected astrocytes were converted into neurons,the number of BrdU-labeled neurons was surprisingly low.To exclude the possibility that this BrdU inhibition was caused by the ischemic injury,we conducted an in vitro AtN conversion study by overexpressing NeuroD1 in cultured cortical astrocytes in the presence or absence of BrdU.Surprisingly,we also found a significantly lower conversion rate and a smaller number of converted neurons in the BrdU-treated group compared with the untreated group.These results revealed an unexpected inhibitory effect of BrdU on AtN conversion,suggesting more caution is needed when using BrdU in AtN conversion studies and in data interpretation.
基金Hainan Provincial Natural Science Foundation of China(No.817141)National Natural Science Foundation of China(No.81460043).
文摘Objective:To investigate the role of baicalein in phenotypic transformation of vascularsmooth muscle cells induced by high glucose.Methods:Rat vascular smooth muscle cellexperiments were divided into control group,baicalein group,high glucose group,highglucose plus baicalein group,real time quantitative PCR were used for mRNA analysis of-SMA,SM22-αnd OPN,Western blot were used for protein analysis of α-SMA,SM22-αand OPN.Results:Comparing the high glucose group and the high glucose plus baicaleingroup,the level of α-SMA mRNA in high glucose group was 0.419±0.090,the level ofα-SMA mRNA in high glucose plus baicalein group was 0.699±0.079,the latter was 66.8%higher than the former.The level of α-SMA protein in high glucose group was 0.213±0.034,the level of α-SMA protein in high glucose plus baicalein group was 0.393±0.062,the latterwas 84.5%higher than the former.Baicalein could significantly inhibit the down-regulationof α-SMA gene expression induced by high glucose(P<0.05).Comparing the high glucosegroup and the high glucose plus baicalein group,the level of SM22-mRNA in high glucosegroup was 0.369±0.063,the level of SM22-α mRNA in high glucose plus baicalein groupwas 0.583±0.049,the latter was 58.0%higher than the former.The level of SM22-α proteinin high glucose group was 0.343±0.047,the level of SM22-protein in high glucose plusbaicalein group was 0.486±0.051,the latter was 41.7%higher than the former.Baicaleincould significantly inhibit the down-regulation of SM22-α gene expression induced by highglucose(P<0.05).Comparing the high glucose group and the high glucose plus baicaleingroup,the level of OPN mRNA in high glucose group was 2.023±0.281,the level of OPNmRNA in high glucose plus baicalein group was 1.511±0.091,the latter was 25.3%lowerthan the former.The level of OPN protein in high glucose group was 1.063±0.132,the levelof OPN protein in high glucose plus baicalein group was 0.761±0.089,the latter was 28.4%lower than the former.Baicalein could significantly inhibit the up-regulation of OPN geneexpression induced by high glucose(P<0.05).Conclusion:Baicalein can significantly inhibitthe high glucose-induced phenotypic transformation of vascular smooth muscle cells fromcontractile phenotype to synthetic phenotype.
基金supported by the Logistics Support Ministry of China (No.22BJZ41)the Capital's Funds for Health Improvement and Research (No.CFH2024-2-5071)。
文摘OBJECTIVE To assess the feasibility and safety of the minimalistic approach to left atrial appendage occlusion(LAAO) guided by cardiac computed tomography angiography(CCTA).METHODS Ninety consecutive patients who underwent LAAO, with or without CCTA-guided, were matched(1:2). Each step of the LAAO procedure in the computed tomography(CT) guidance group(CT group) was directed by preprocedural CT planning. In the control group, LAAO was performed using the standard method. All patients were followed up for 12 months, and device surveillance was conducted using CCTA.RESULTS A total of 90 patients were included in the analysis, with 30 patients in the CT group and 60 matched patients in the control group. All patients were successfully implanted with Watchman devices. The mean ages for the CT group and the control group were 70.0 ± 9.4 years and 68.4 ± 11.9 years(P = 0.52), respectively. The procedure duration(45.6 ± 10.7 min vs. 58.8 ± 13.0 min,P < 0.001) and hospital stay(7.5 ± 2.4 day vs. 9.6 ± 2.8 day, P = 0.001) in the CT group was significantly shorter compared to the control group. However, the total radiation dose was higher in the CT group compared to the control group(904.9 ± 348.0 m Gy vs.711.9 ± 211.2 m Gy, P = 0.002). There were no significant differences in periprocedural pericardial effusion(3.3% vs. 6.3%, P = 0.8) between the two groups. The rate of postprocedural adverse events(13.3% vs. 18.3%, P = 0.55) were comparable between both groups at 12 months follow-up.CONCLUSIONS CCTA is capable of detailed LAAO procedure planning. Minimalistic LAAO with preprocedural CCTA planning was feasible and safe, with shortened procedure time and acceptable increased radiation and contras consumption. For patients with contraindications to general anesthesia and/or transesophageal echocardiography, this promising method may be an alternative to conventional LAAO.
基金supported by a Chongqing Social Science Plan Project(2015YBSH142)
文摘Dementia is increasing dramatically and imposes a huge burden on society. To date, there is a lack of data on the health status of patients with dementia in China. In an attempt to investigate the comorbidity burden of dementia patients in China at the national level, we enrolled 2,938 patients with Alzheimer's disease(AD), vascular dementia(Va D), or other types of dementia, who were admitted to tertiary hospitals in seven regions of China from January2003 to December 2012. The Charlson Comorbidity Index(CCI) was used to evaluate the comorbidity burden of the patients with dementia. Among these patients, 53.4% had AD, 26.3% had Va D, and 20.3% had other types of dementia. The CCI was 3.0 ± 1.9 for all patients,3.4 ± 1.8 for those with Va D, and 3.0 ± 2.1 for those with AD. The CCI increased with age in all patients, andthe length of hospital stay and daily expenses rose with age and CCI. Males had a higher CCI and a longer stay than females. Moreover, patients admitted in the last 5 years of the study had a higher CCI than those admitted in the first 5 years. We found that the comorbidity burden of patients with dementia is heavy. These findings provide a better understanding of the overall health status of dementia patients, and help to increase the awareness of clinicians and policy-makers to improve medical care for patients.
