In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial cells.However,the functional role of GGT5 in the development of A...In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial cells.However,the functional role of GGT5 in the development of Alzheimer’s disease remains unclear.This study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer’s disease,as well as the underlying mechanism.We observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer’s disease(Aβ_(1-42)-treated hCMEC/D3 and bEnd.3 cells),as well as in the APP/PS1 mouse model.Additionally,injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive deficits.Interestingly,increasing GGT5 expression in cerebrovascular endothelial cells reduced levels of both soluble and insoluble amyloid-βin the brains of APP/PS1 mice.This effect may be attributable to inhibition of the expression ofβ-site APP cleaving enzyme 1,which is mediated by nuclear factor-kappa B.Our findings demonstrate that GGT5 expression in cerebrovascular endothelial cells is inversely associated with Alzheimer’s disease pathogenesis,and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 mice.These findings suggest that GGT5 expression in cerebrovascular endothelial cells is a potential therapeutic target and biomarker for Alzheimer’s disease.展开更多
The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control system.In this study,we aimed...The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control system.In this study,we aimed to investigate the neuroprotective effect of overexpressed CHIP on Alzheimer’s disease.We used an adeno-associated virus vector that can cross the blood-brain barrier to mediate CHIP overexpression in APP/PS1 mouse brain.CHIP overexpression significantly ameliorated the performance of APP/PS1 mice in the Morris water maze and nest building tests,reduced amyloid-βplaques,and decreased the expression of both amyloid-βand phosphorylated tau.CHIP also alleviated the concentration of microglia and astrocytes around plaques.In APP/PS1 mice of a younger age,CHIP overexpression promoted an increase in ADAM10 expression and inhibitedβ-site APP cleaving enzyme 1,insulin degrading enzyme,and neprilysin expression.Levels of HSP70 and HSP40,which have functional relevance to CHIP,were also increased.Single nuclei transcriptome sequencing in the hippocampus of CHIP overexpressed mice showed that the lysosomal pathway and oligodendrocyte-related biological processes were up-regulated,which may also reflect a potential mechanism for the neuroprotective effect of CHIP.Our research shows that CHIP effectively reduces the behavior and pathological manifestations of APP/PS1 mice.Indeed,overexpression of CHIP could be a beneficial approach for the treatment of Alzheimer’s disease.展开更多
Alzheimer's disease is a progressive neurological disorder characterized by cognitive decline and chronic inflammation within the brain.The ketogenic diet,a widely recognized therapeutic intervention for refractor...Alzheimer's disease is a progressive neurological disorder characterized by cognitive decline and chronic inflammation within the brain.The ketogenic diet,a widely recognized therapeutic intervention for refractory epilepsy,has recently been proposed as a potential treatment for a variety of neurological diseases,including Alzheimer's disease.However,the efficacy of ketogenic diet in treating Alzheimer's disease and the underlying mechanism remains unclear.The current investigation aimed to explore the effect of ketogenic diet on cognitive function and the underlying biological mechanisms in a mouse model of Alzheimer's disease.Male amyloid precursor protein/presenilin 1(APP/PS1)mice were randomly assigned to either a ketogenic diet or control diet group,and received their respective diets for a duration of 3 months.The findings show that ketogenic diet administration enhanced cognitive function,attenuated amyloid plaque formation and proinflammatory cytokine levels in APP/PS1 mice,and augmented the nuclear factor-erythroid 2-p45 derived factor 2/heme oxygenase-1 signaling pathway while suppressing the nuclear factor-kappa B pathway.Collectively,these data suggest that ketogenic diet may have a therapeutic potential in treating Alzheimer's disease by ameliorating the neurotoxicity associated with Aβ-induced inflammation.This study highlights the urgent need for further research into the use of ketogenic diet as a potential therapy for Alzheimer's disease.展开更多
OBJECTIVE To study the protective effect of potassium 2-(l-hydroxypentyl)-benzoate(PHPB) on hippocampal neurons,synapses and dystrophic axons in APP/PS1 mice.METHODS Ten-month-old male APP/PS1 transgenic mice and age-...OBJECTIVE To study the protective effect of potassium 2-(l-hydroxypentyl)-benzoate(PHPB) on hippocampal neurons,synapses and dystrophic axons in APP/PS1 mice.METHODS Ten-month-old male APP/PS1 transgenic mice and age-matched wild-type mice were randomly divided into three groups:wild-type group(WT Con group,n=10),APP/PS1 group(Tg Con group,n=10) and PHPB treated APP/PS1 group(PHPB group,n=10).PHPB group received 30 mg · kg-1 PHPB by oral gavage once daily for 3 months.WT Con group and Tg Con group received the same volume of water.Three months later,mice were sacrificed for biochemical and pathological testing such as transmission electron microscopy,Golgi staining and Western boltting analysis.RESULTS Under the transmission electron microscope,most hippocampal neurons and subcel ular organel es in WT Con group exhibited normal morphology.However,the degenerative changes were observed in Tg Con group such as nuclear fragmentation,mitochondrial swelling,ribosomes detachment and autophagic vacuoles accumulation.The hippocampal synapses number and the thickness of postsynaptic density(PSD) were significantly decreased in Tg Con group compared with the WT Con group(P<0.05).After PHPB treatment,the degenerative changes in APP/PS1 mice were alleviated to some extent.The synapse number has been elevated significantly(P<0.05) and the PSD has been thickened as well.Golgi staining showed that the spine density of secondary and tertiary apical dendritic branches was significantly decreased in CA1 and DG areas of Tg Con group(P<0.05).Sholl analysis revealed a decrease of dendritic complexity in Tg Con group compared with WT Con group(P<0.05).These abnormalities were alleviated to some extent after PHPB treatment.Western blotting study showed that the protein levels of synaptic marker PSD-95 and synaptophysin were significantly decreased in the hippocampus of Tg Con group(P<0.05).A significant increase of PSD-95(P<0.05) and a slight increase of SYP were observed after the PHPB treatment.Besides,we found a significant increase in the ratio of LC3-Ⅱ/LC3-Ⅰ in Tg Con group compared with the WT Con group(P<0.01) and the relevant improvement after PHPB treatment(P<0.05),which showed the regulatory effect of PHPB on autophagy impairment.CONCLUSION PHPB showed protective effects on hippocampal neurons,synapses and dystrophic axons in APP/PS1 mice,which might help explain its role on cognitive improvement in Alzheimer disease treatment.展开更多
Alzheimer's disease(AD)is a neurodegenerative disorder strongly correlated with dysfunctional immune system.Our previous results demonstrated that inactivated influenza vaccine(IV)facilitated hippocampal neurogene...Alzheimer's disease(AD)is a neurodegenerative disorder strongly correlated with dysfunctional immune system.Our previous results demonstrated that inactivated influenza vaccine(IV)facilitated hippocampal neurogenesis.However,whether IV could improve cognitive deficits in AD mouse model remains unclear.展开更多
Behavioral experiments have demonstrated that long-term physical exercise can be beneficial for learning and memory dysfunction caused by neuroinflammation in Alzheimer's disease(AD).However,the molecular mechanis...Behavioral experiments have demonstrated that long-term physical exercise can be beneficial for learning and memory dysfunction caused by neuroinflammation in Alzheimer's disease(AD).However,the molecular mechanism remains poorly understood due to a lack of sufficient pertinent biochemical evidence.We investigated the potential effect of long-term physical exercise on cognition and hippocampal gene and protein expression changes in a transgenic AD mouse model.Following twenty weeks of treadmill exercise,transgenic AD mice showed improvement in cognitive functions and downregulation of Nod-like receptor protein 3(NLRP3)(p<0.01),interleukin-1beta(IL-1β)(p<0.05),and amyloid-β1-42(Aβ1-42)(p<0.05)expression levels.In addition,we observed significant reductions of microglial activation and hippocampal neuronal damage in the exercised AD mice(p<0.01),which might be a result of the downregulation of NLRP3-mediated signaling and neuroinflammatory responses.As neuronal damage due to inflammation might be a likely cause of AD-associated cognitive dysfunction.Our results suggested that the anti-inflammatory effects of exercise training involved downregulating the expression of key inflammatory factors and might play an important role in protecting hippocampal neurons against damage during the course of AD.展开更多
基金supported by STI2030-Major Projects,No.2021ZD 0201801(to JG)Shanxi Province Basic Research Program,No.20210302123429(to QS).
文摘In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial cells.However,the functional role of GGT5 in the development of Alzheimer’s disease remains unclear.This study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer’s disease,as well as the underlying mechanism.We observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer’s disease(Aβ_(1-42)-treated hCMEC/D3 and bEnd.3 cells),as well as in the APP/PS1 mouse model.Additionally,injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive deficits.Interestingly,increasing GGT5 expression in cerebrovascular endothelial cells reduced levels of both soluble and insoluble amyloid-βin the brains of APP/PS1 mice.This effect may be attributable to inhibition of the expression ofβ-site APP cleaving enzyme 1,which is mediated by nuclear factor-kappa B.Our findings demonstrate that GGT5 expression in cerebrovascular endothelial cells is inversely associated with Alzheimer’s disease pathogenesis,and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 mice.These findings suggest that GGT5 expression in cerebrovascular endothelial cells is a potential therapeutic target and biomarker for Alzheimer’s disease.
基金supported by the National Natural Science Foundation of China,Nos.91849115 and U1904207(to YX),81974211 and 82171247(to CS)Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences,No.2020-PT310-01(to YX).
文摘The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control system.In this study,we aimed to investigate the neuroprotective effect of overexpressed CHIP on Alzheimer’s disease.We used an adeno-associated virus vector that can cross the blood-brain barrier to mediate CHIP overexpression in APP/PS1 mouse brain.CHIP overexpression significantly ameliorated the performance of APP/PS1 mice in the Morris water maze and nest building tests,reduced amyloid-βplaques,and decreased the expression of both amyloid-βand phosphorylated tau.CHIP also alleviated the concentration of microglia and astrocytes around plaques.In APP/PS1 mice of a younger age,CHIP overexpression promoted an increase in ADAM10 expression and inhibitedβ-site APP cleaving enzyme 1,insulin degrading enzyme,and neprilysin expression.Levels of HSP70 and HSP40,which have functional relevance to CHIP,were also increased.Single nuclei transcriptome sequencing in the hippocampus of CHIP overexpressed mice showed that the lysosomal pathway and oligodendrocyte-related biological processes were up-regulated,which may also reflect a potential mechanism for the neuroprotective effect of CHIP.Our research shows that CHIP effectively reduces the behavior and pathological manifestations of APP/PS1 mice.Indeed,overexpression of CHIP could be a beneficial approach for the treatment of Alzheimer’s disease.
基金the National Natural Science Foundation of China,Nos.82171401,81971187(to SC)and 81971183(to YT)grants from Shanghai Municipal Science and Technology Major Project,No.2018SHZDZX05(to SC)Shanghai Municipal Education Commission,No.2017-01-07-00-01-E00046(to SC)。
文摘Alzheimer's disease is a progressive neurological disorder characterized by cognitive decline and chronic inflammation within the brain.The ketogenic diet,a widely recognized therapeutic intervention for refractory epilepsy,has recently been proposed as a potential treatment for a variety of neurological diseases,including Alzheimer's disease.However,the efficacy of ketogenic diet in treating Alzheimer's disease and the underlying mechanism remains unclear.The current investigation aimed to explore the effect of ketogenic diet on cognitive function and the underlying biological mechanisms in a mouse model of Alzheimer's disease.Male amyloid precursor protein/presenilin 1(APP/PS1)mice were randomly assigned to either a ketogenic diet or control diet group,and received their respective diets for a duration of 3 months.The findings show that ketogenic diet administration enhanced cognitive function,attenuated amyloid plaque formation and proinflammatory cytokine levels in APP/PS1 mice,and augmented the nuclear factor-erythroid 2-p45 derived factor 2/heme oxygenase-1 signaling pathway while suppressing the nuclear factor-kappa B pathway.Collectively,these data suggest that ketogenic diet may have a therapeutic potential in treating Alzheimer's disease by ameliorating the neurotoxicity associated with Aβ-induced inflammation.This study highlights the urgent need for further research into the use of ketogenic diet as a potential therapy for Alzheimer's disease.
基金National Natural Sciences Foundation of China(8147320081673420)CAMS InnovationFund for Medical Sciences (2017-I2M-2-004).
文摘OBJECTIVE To study the protective effect of potassium 2-(l-hydroxypentyl)-benzoate(PHPB) on hippocampal neurons,synapses and dystrophic axons in APP/PS1 mice.METHODS Ten-month-old male APP/PS1 transgenic mice and age-matched wild-type mice were randomly divided into three groups:wild-type group(WT Con group,n=10),APP/PS1 group(Tg Con group,n=10) and PHPB treated APP/PS1 group(PHPB group,n=10).PHPB group received 30 mg · kg-1 PHPB by oral gavage once daily for 3 months.WT Con group and Tg Con group received the same volume of water.Three months later,mice were sacrificed for biochemical and pathological testing such as transmission electron microscopy,Golgi staining and Western boltting analysis.RESULTS Under the transmission electron microscope,most hippocampal neurons and subcel ular organel es in WT Con group exhibited normal morphology.However,the degenerative changes were observed in Tg Con group such as nuclear fragmentation,mitochondrial swelling,ribosomes detachment and autophagic vacuoles accumulation.The hippocampal synapses number and the thickness of postsynaptic density(PSD) were significantly decreased in Tg Con group compared with the WT Con group(P<0.05).After PHPB treatment,the degenerative changes in APP/PS1 mice were alleviated to some extent.The synapse number has been elevated significantly(P<0.05) and the PSD has been thickened as well.Golgi staining showed that the spine density of secondary and tertiary apical dendritic branches was significantly decreased in CA1 and DG areas of Tg Con group(P<0.05).Sholl analysis revealed a decrease of dendritic complexity in Tg Con group compared with WT Con group(P<0.05).These abnormalities were alleviated to some extent after PHPB treatment.Western blotting study showed that the protein levels of synaptic marker PSD-95 and synaptophysin were significantly decreased in the hippocampus of Tg Con group(P<0.05).A significant increase of PSD-95(P<0.05) and a slight increase of SYP were observed after the PHPB treatment.Besides,we found a significant increase in the ratio of LC3-Ⅱ/LC3-Ⅰ in Tg Con group compared with the WT Con group(P<0.01) and the relevant improvement after PHPB treatment(P<0.05),which showed the regulatory effect of PHPB on autophagy impairment.CONCLUSION PHPB showed protective effects on hippocampal neurons,synapses and dystrophic axons in APP/PS1 mice,which might help explain its role on cognitive improvement in Alzheimer disease treatment.
文摘Alzheimer's disease(AD)is a neurodegenerative disorder strongly correlated with dysfunctional immune system.Our previous results demonstrated that inactivated influenza vaccine(IV)facilitated hippocampal neurogenesis.However,whether IV could improve cognitive deficits in AD mouse model remains unclear.
基金the Sports Medicine Key Laboratory of Sichuan Province/Sports Medicine Key Laboratory of State Sport General Administration(Grant No.2023-A015)the Innovative Project of Sports Medicine and Health Institute/Zheng Huaixian Bone and Trauma Research Institute(Grant No.CX21A02)the"14th Five Year Plan"Scientific Research and Innovation Team of Chengdu Sport University(Grant No.23CXTD02).
文摘Behavioral experiments have demonstrated that long-term physical exercise can be beneficial for learning and memory dysfunction caused by neuroinflammation in Alzheimer's disease(AD).However,the molecular mechanism remains poorly understood due to a lack of sufficient pertinent biochemical evidence.We investigated the potential effect of long-term physical exercise on cognition and hippocampal gene and protein expression changes in a transgenic AD mouse model.Following twenty weeks of treadmill exercise,transgenic AD mice showed improvement in cognitive functions and downregulation of Nod-like receptor protein 3(NLRP3)(p<0.01),interleukin-1beta(IL-1β)(p<0.05),and amyloid-β1-42(Aβ1-42)(p<0.05)expression levels.In addition,we observed significant reductions of microglial activation and hippocampal neuronal damage in the exercised AD mice(p<0.01),which might be a result of the downregulation of NLRP3-mediated signaling and neuroinflammatory responses.As neuronal damage due to inflammation might be a likely cause of AD-associated cognitive dysfunction.Our results suggested that the anti-inflammatory effects of exercise training involved downregulating the expression of key inflammatory factors and might play an important role in protecting hippocampal neurons against damage during the course of AD.