Alzheimer’s disease (AD) is the most prevalent cause of dementia worldwide. Because of the progressive neurodegeneration, individual cognitive and behavioral functions are impaired, affecting the quality of life of m...Alzheimer’s disease (AD) is the most prevalent cause of dementia worldwide. Because of the progressive neurodegeneration, individual cognitive and behavioral functions are impaired, affecting the quality of life of millions of people. Although the exact pathogenesis of AD has not been fully elucidated, amyloid plaques, neurofibrillary tangles (NFTs), and sustaining neuroinflammation dominate its characteristics. As one of the major tau kinases leading to hyperphosphorylation and aggregation of tau, glycogen synthase kinase-3β (GSK-3β) has been drawing great attention in various AD studies. Another research focus of AD in recent years is the inflammasome, a multiprotein complex acting as a regulator in immunological reactions to exogenous and endogenous danger signals, of which the Nod-like receptor (NLR) family, pyrin domain-containing 3 (NLRP3) inflammasome has been studied mostly in AD and proven to play a significant role in AD development by its activation and downstream effects such as caspase-1 maturation and interleukin (IL)-1β release. Studies have shown that the NLRP3 inflammasome is activated in a GSK-3β-dependent way and that inhibition of the NLRP3 inflammasome downregulates GSK-3β, suggesting that these two important proteins are closely related. This article reviews the respective roles of GSK-3β and the NLRP3 inflammasome in AD as well as their relationship and interaction.展开更多
Interleukin-4(IL-4) has a protective effect against cerebral ischemia/reperfusion injury. Animal experiments have shown that IL-4 improves the short-and long-term prognosis of neurological function. The Akt(also calle...Interleukin-4(IL-4) has a protective effect against cerebral ischemia/reperfusion injury. Animal experiments have shown that IL-4 improves the short-and long-term prognosis of neurological function. The Akt(also called protein kinase B, PKB)/glycogen synthase kinase-3β(Akt/GSK-3β) signaling pathway is involved in oxidative stress, the inflammatory response, apoptosis, and autophagy. However, it is not yet clear whether the Akt/GSK-3β pathway participates in the neuroprotective effect of IL-4 against cerebral ischemia/reperfusion injury. In the present study, we established a cerebral ischemia/reperfusion mouse model by middle cerebral artery occlusion for 60 minutes followed by a 24-hour reperfusion. An IL-4/anti-IL-4 complex(10 μg) was intraperitoneally administered 30 minutes before surgery. We found that administration of IL-4 significantly alleviated the neurological deficits, oxidative stress, cell apoptosis, and autophagy and reduced infarct volume of the mice with cerebral ischemia/reperfusion injury 24 hours after reperfusion. Simultaneously, IL-4 activated Akt/GSK-3β signaling pathway. However, an Akt inhibitor LY294002, which was injected at 15 nmol/kg via the tail vein, attenuated the protective effects of IL-4. These findings indicate that IL-4 has a protective effect on cerebral ischemia/reperfusion injury by mitigating oxidative stress, reducing apoptosis, and inhibiting excessive autophagy, and that this mechanism may be related to activation of the Akt/GSK-3β pathway. This animal study was approved by the Animal Ethics Committee of Renmin Hospital of Wuhan University, China(approval No. WDRY2017-K037) on March 9, 2017.展开更多
Objective:Glycogen synthase kinase-3β(GSK3β)has been recognized as a suppressor of Wnt/β-catenin signaling,which is critical for the stemness maintenance of breast cancer stem cells.However,the regulatory mechanism...Objective:Glycogen synthase kinase-3β(GSK3β)has been recognized as a suppressor of Wnt/β-catenin signaling,which is critical for the stemness maintenance of breast cancer stem cells.However,the regulatory mechanisms of GSK3βprotein expression remain elusive.Methods:Co-immunoprecipitation and mass spectral assays were performed to identify molecules binding to GSK3β,and to characterize the interactions of GSK3β,heat shock protein 90(Hsp90),and co-chaperones.The role of PGK1 in Hsp90 chaperoning GSK3βwas evaluated by constructing 293T cells stably expressing different domains/mutants of Hsp90α,and by performing a series of binding assays with bacterially purified proteins and clinical specimens.The influences of Hsp90 inhibitors on breast cancer stem cell stemness were investigated by Western blot and mammosphere formation assays.Results:We showed that GSK3βwas a client protein of Hsp90.Hsp90,which did not directly bind to GSK3β,interacted with phosphoglycerate kinase 1 via its C-terminal domain,thereby facilitating the binding of GSK3βto Hsp90.GSK3β-bound PGK1 interacted with Hsp90 in the“closed”conformation and stabilized GSK3βexpression in an Hsp90 activity-dependent manner.The Hsp90 inhibitor,17-AAG,rather than HDN-1,disrupted the interaction between Hsp90 and PGK1,and reduced GSK3βexpression,resulting in significantly reduced inhibition ofβ-catenin expression,to maintain the stemness of breast cancer stem cells.Conclusions:Our findings identified a novel regulatory mechanism of GSK3βexpression involving metabolic enzyme PGK1-coupled Hsp90,and highlighted the potential for more effective cancer treatment by selecting Hsp90 inhibitors that do not affect PGK1-regulated GSK3βexpression.展开更多
Inhibition ofβ-site amyloid precursor protein-cleaving enzyme 1(BACE1)or glycogen synthase kinase-3β(GSK-3β)is estimated to be the central therapeutic approach for Alzheimer’s disease(AD).In this study,water extra...Inhibition ofβ-site amyloid precursor protein-cleaving enzyme 1(BACE1)or glycogen synthase kinase-3β(GSK-3β)is estimated to be the central therapeutic approach for Alzheimer’s disease(AD).In this study,water extract of Kangenkaryu,its crude drug and chemical composition used in oriental medicine were evaluated regarding their BACE1 and GSK-3βinhibitory activities.Fluorescence resonance energy transfer was used to characterize the BACE1 inhibitory effect of Kangen-karyu,its crude drug and chemical composition.GSK-3βactivity was determined using the Kinase-Glo Luminescent Kinase Assay Platform.The water extract of Kangen-karyu inhibited BACE1 and GSK-3βin concentration-dependent manners when compared with reference drugs,quercetin and luteolin.Among six components of Kangen-karyu,the water extracts of Salviae Miltiorrhizae Radix or Cyperi Rhizoma exhibited significant inhibitory effects on BACE1 and GSK-3β.Among the constituents of Salviae Miltiorrhizae Radix extract,salvianolic acid C,salvianolic acid A,rosmarinic acid,and magnesium lithospermate B significantly inhibited BACE1.In addition,they inhibited GSK-3βwith an IC50 value range of 6.97 to 135.35μM.From these results,one of the effectiveness and its mechanisms of action of Kangen-karyu against AD may be the inhibition of BACE1 and GSK-3β,and one of the active ingredients of Kangen-karyu is Salviae Miltiorrhizae Radix and its constituents.展开更多
In Alzheimer’s disease and ischemic stroke,intranasal insulin can act as a neuroprotective agent.However,whether intranasal insulin has a neuroprotective effect in intracerebral hemorrhage and its potential mechanism...In Alzheimer’s disease and ischemic stroke,intranasal insulin can act as a neuroprotective agent.However,whether intranasal insulin has a neuroprotective effect in intracerebral hemorrhage and its potential mechanisms remain poorly understood.In this study,a mouse model of autologous blood-induced intracerebral hemorrhage was treated with 0.5,1,or 2 IU insulin via intranasal delivery,twice per day,until 24 or 72 hours after surgery.Compared with saline treatment,1 IU intranasal insulin treatment significantly reduced hematoma volume and brain edema after cerebral hemorrhage,decreased blood-brain barrier permeability and neuronal degeneration damage,reduced neurobehavioral deficits,and improved the survival rate of mice.Expression levels of p-AKT and p-GSK3βwere significantly increased in the perihematoma tissues after intranasal insulin therapy.Our findings suggest that intranasal insulin therapy can protect the neurological function of mice after intracerebral hemorrhage through the AKT/GSK3βsignaling pathway.The study was approved by the Ethics Committee of the North Sichuan Medical College of China(approval No.NSMC(A)2019(01))on January 7,2019.展开更多
Postmenopausal women with Alzheimer’s disease exhibit dramatically reduced sensitivity to estrogen replacement therapy,which is though to be related to an estrogen receptor(ER)α/ERβratio imbalance arising from a si...Postmenopausal women with Alzheimer’s disease exhibit dramatically reduced sensitivity to estrogen replacement therapy,which is though to be related to an estrogen receptor(ER)α/ERβratio imbalance arising from a significantly decreased level of ERs of the brain.The aim of our study was to investigate whether valproic acid(VPA)can enhance the beneficial effects of estrogen on cognitive function through restoration of ERαand ERβexpression in the brain.We removed the ovaries of female APP/PS1 mice to simulate the low estrogen levels present in postmenopausal women and then administered VPA(30 mg/kg,intraperitoneal injection,once daily),17β-estradiol(E2)(2.4μg,intraperitoneal injection,once daily),liquiritigenin(LG)(50μg/kg,intragastric infusion,once daily),VPA+E2,or VPA+LG for 4 successive weeks.Compared with treatment with a single drug,treatment with VPA+E2 or VPA+LG significantly increased the level of glycogen synthase kinase 3β,increased the expression of estrogen receptorα,reduced the expression of small ubiquitin-like modifiers,and increased the level of estrogen receptorβ.This resulted in enhanced sensitivity to estrogen therapy,reduced amyloidβaggregation,reduced abnormal phosphorylation of the tau protein,reduced neuronal loss,increased dendritic spine and postsynaptic density,and significantly alleviated memory loss and learning impairment in Alzheimer’s disease.This study was approved by the Chongqing Medical University Animal Protection and Ethics Committee,China on March 6,2013.展开更多
基金supported by grants from the National Natural Science Foundation of China(No.92049107 and No.31929002)the Innovative Research Groups of the National Natural Science Foundation of China(No.81721005)the Academic Frontier Youth Team Project to Xiaochuan Wang from Huazhong University of Science and Technology.
文摘Alzheimer’s disease (AD) is the most prevalent cause of dementia worldwide. Because of the progressive neurodegeneration, individual cognitive and behavioral functions are impaired, affecting the quality of life of millions of people. Although the exact pathogenesis of AD has not been fully elucidated, amyloid plaques, neurofibrillary tangles (NFTs), and sustaining neuroinflammation dominate its characteristics. As one of the major tau kinases leading to hyperphosphorylation and aggregation of tau, glycogen synthase kinase-3β (GSK-3β) has been drawing great attention in various AD studies. Another research focus of AD in recent years is the inflammasome, a multiprotein complex acting as a regulator in immunological reactions to exogenous and endogenous danger signals, of which the Nod-like receptor (NLR) family, pyrin domain-containing 3 (NLRP3) inflammasome has been studied mostly in AD and proven to play a significant role in AD development by its activation and downstream effects such as caspase-1 maturation and interleukin (IL)-1β release. Studies have shown that the NLRP3 inflammasome is activated in a GSK-3β-dependent way and that inhibition of the NLRP3 inflammasome downregulates GSK-3β, suggesting that these two important proteins are closely related. This article reviews the respective roles of GSK-3β and the NLRP3 inflammasome in AD as well as their relationship and interaction.
基金supported by the National Natural Science Foundation of China,Nos.81901994(to BZ)and 81571147(to XXX)the Natural Science Foundation of Hubei Province,China,No.2019CFC847(to WWG)the Fundamental Research Funds for the Central Universities,China,No.2042018kf0149(to ML)
文摘Interleukin-4(IL-4) has a protective effect against cerebral ischemia/reperfusion injury. Animal experiments have shown that IL-4 improves the short-and long-term prognosis of neurological function. The Akt(also called protein kinase B, PKB)/glycogen synthase kinase-3β(Akt/GSK-3β) signaling pathway is involved in oxidative stress, the inflammatory response, apoptosis, and autophagy. However, it is not yet clear whether the Akt/GSK-3β pathway participates in the neuroprotective effect of IL-4 against cerebral ischemia/reperfusion injury. In the present study, we established a cerebral ischemia/reperfusion mouse model by middle cerebral artery occlusion for 60 minutes followed by a 24-hour reperfusion. An IL-4/anti-IL-4 complex(10 μg) was intraperitoneally administered 30 minutes before surgery. We found that administration of IL-4 significantly alleviated the neurological deficits, oxidative stress, cell apoptosis, and autophagy and reduced infarct volume of the mice with cerebral ischemia/reperfusion injury 24 hours after reperfusion. Simultaneously, IL-4 activated Akt/GSK-3β signaling pathway. However, an Akt inhibitor LY294002, which was injected at 15 nmol/kg via the tail vein, attenuated the protective effects of IL-4. These findings indicate that IL-4 has a protective effect on cerebral ischemia/reperfusion injury by mitigating oxidative stress, reducing apoptosis, and inhibiting excessive autophagy, and that this mechanism may be related to activation of the Akt/GSK-3β pathway. This animal study was approved by the Animal Ethics Committee of Renmin Hospital of Wuhan University, China(approval No. WDRY2017-K037) on March 9, 2017.
基金This work was supported by grants from the NSFC Shandong Joint Fund(Grant No.U1606403)the National Natural Science Foundation of China(Grant No.81673450)+4 种基金the State Key Program of the National Natural Science Foundation of China(Grant No.82030074)the NSFC-Shandong Joint Fund(Grant No.U1906212)the Qingdao National Laboratory for Marine Science and Technology(Grant No.2015ASKJ02)the National Science and Technology Major Project for Significant New Drugs Development(Grant No.2018ZX09735-004)the Shandong Provincial Natural Science Foundation(major basic research projects,Grant No.ZR2019ZD18).
文摘Objective:Glycogen synthase kinase-3β(GSK3β)has been recognized as a suppressor of Wnt/β-catenin signaling,which is critical for the stemness maintenance of breast cancer stem cells.However,the regulatory mechanisms of GSK3βprotein expression remain elusive.Methods:Co-immunoprecipitation and mass spectral assays were performed to identify molecules binding to GSK3β,and to characterize the interactions of GSK3β,heat shock protein 90(Hsp90),and co-chaperones.The role of PGK1 in Hsp90 chaperoning GSK3βwas evaluated by constructing 293T cells stably expressing different domains/mutants of Hsp90α,and by performing a series of binding assays with bacterially purified proteins and clinical specimens.The influences of Hsp90 inhibitors on breast cancer stem cell stemness were investigated by Western blot and mammosphere formation assays.Results:We showed that GSK3βwas a client protein of Hsp90.Hsp90,which did not directly bind to GSK3β,interacted with phosphoglycerate kinase 1 via its C-terminal domain,thereby facilitating the binding of GSK3βto Hsp90.GSK3β-bound PGK1 interacted with Hsp90 in the“closed”conformation and stabilized GSK3βexpression in an Hsp90 activity-dependent manner.The Hsp90 inhibitor,17-AAG,rather than HDN-1,disrupted the interaction between Hsp90 and PGK1,and reduced GSK3βexpression,resulting in significantly reduced inhibition ofβ-catenin expression,to maintain the stemness of breast cancer stem cells.Conclusions:Our findings identified a novel regulatory mechanism of GSK3βexpression involving metabolic enzyme PGK1-coupled Hsp90,and highlighted the potential for more effective cancer treatment by selecting Hsp90 inhibitors that do not affect PGK1-regulated GSK3βexpression.
文摘Inhibition ofβ-site amyloid precursor protein-cleaving enzyme 1(BACE1)or glycogen synthase kinase-3β(GSK-3β)is estimated to be the central therapeutic approach for Alzheimer’s disease(AD).In this study,water extract of Kangenkaryu,its crude drug and chemical composition used in oriental medicine were evaluated regarding their BACE1 and GSK-3βinhibitory activities.Fluorescence resonance energy transfer was used to characterize the BACE1 inhibitory effect of Kangen-karyu,its crude drug and chemical composition.GSK-3βactivity was determined using the Kinase-Glo Luminescent Kinase Assay Platform.The water extract of Kangen-karyu inhibited BACE1 and GSK-3βin concentration-dependent manners when compared with reference drugs,quercetin and luteolin.Among six components of Kangen-karyu,the water extracts of Salviae Miltiorrhizae Radix or Cyperi Rhizoma exhibited significant inhibitory effects on BACE1 and GSK-3β.Among the constituents of Salviae Miltiorrhizae Radix extract,salvianolic acid C,salvianolic acid A,rosmarinic acid,and magnesium lithospermate B significantly inhibited BACE1.In addition,they inhibited GSK-3βwith an IC50 value range of 6.97 to 135.35μM.From these results,one of the effectiveness and its mechanisms of action of Kangen-karyu against AD may be the inhibition of BACE1 and GSK-3β,and one of the active ingredients of Kangen-karyu is Salviae Miltiorrhizae Radix and its constituents.
基金supported by the National Natural Science Foundation of China,No.81971220a grant from the Science and Technology Department of Sichuan Province of China,No.2018JY0236(both to GHJ)。
文摘In Alzheimer’s disease and ischemic stroke,intranasal insulin can act as a neuroprotective agent.However,whether intranasal insulin has a neuroprotective effect in intracerebral hemorrhage and its potential mechanisms remain poorly understood.In this study,a mouse model of autologous blood-induced intracerebral hemorrhage was treated with 0.5,1,or 2 IU insulin via intranasal delivery,twice per day,until 24 or 72 hours after surgery.Compared with saline treatment,1 IU intranasal insulin treatment significantly reduced hematoma volume and brain edema after cerebral hemorrhage,decreased blood-brain barrier permeability and neuronal degeneration damage,reduced neurobehavioral deficits,and improved the survival rate of mice.Expression levels of p-AKT and p-GSK3βwere significantly increased in the perihematoma tissues after intranasal insulin therapy.Our findings suggest that intranasal insulin therapy can protect the neurological function of mice after intracerebral hemorrhage through the AKT/GSK3βsignaling pathway.The study was approved by the Ethics Committee of the North Sichuan Medical College of China(approval No.NSMC(A)2019(01))on January 7,2019.
基金This study was supported by the National Natural Science Foundation of China,Nos.81671257,81371221,31600825(all to GQH).
文摘Postmenopausal women with Alzheimer’s disease exhibit dramatically reduced sensitivity to estrogen replacement therapy,which is though to be related to an estrogen receptor(ER)α/ERβratio imbalance arising from a significantly decreased level of ERs of the brain.The aim of our study was to investigate whether valproic acid(VPA)can enhance the beneficial effects of estrogen on cognitive function through restoration of ERαand ERβexpression in the brain.We removed the ovaries of female APP/PS1 mice to simulate the low estrogen levels present in postmenopausal women and then administered VPA(30 mg/kg,intraperitoneal injection,once daily),17β-estradiol(E2)(2.4μg,intraperitoneal injection,once daily),liquiritigenin(LG)(50μg/kg,intragastric infusion,once daily),VPA+E2,or VPA+LG for 4 successive weeks.Compared with treatment with a single drug,treatment with VPA+E2 or VPA+LG significantly increased the level of glycogen synthase kinase 3β,increased the expression of estrogen receptorα,reduced the expression of small ubiquitin-like modifiers,and increased the level of estrogen receptorβ.This resulted in enhanced sensitivity to estrogen therapy,reduced amyloidβaggregation,reduced abnormal phosphorylation of the tau protein,reduced neuronal loss,increased dendritic spine and postsynaptic density,and significantly alleviated memory loss and learning impairment in Alzheimer’s disease.This study was approved by the Chongqing Medical University Animal Protection and Ethics Committee,China on March 6,2013.
