End-stage liver diseases,such as cirrhosis and liver cancer caused by hepatitis B,are often combined with hepatic encephalopathy(HE);ammonia poisoning is posited as one of its main pathogenesis mechanisms.Ammonia is c...End-stage liver diseases,such as cirrhosis and liver cancer caused by hepatitis B,are often combined with hepatic encephalopathy(HE);ammonia poisoning is posited as one of its main pathogenesis mechanisms.Ammonia is closely related to autophagy,but the molecular mechanism of ammonia’s regulatory effect on autophagy in HE remains unclear.Sialylation is an essential form of glycosylation.In the nervous system,abnormal sialylation affects various physiological processes,such as neural development and synapse formation.ST3 β-galactoside α2,3-sialyltransferase 6(ST3GAL6)is one of the significant glycosyltransferases responsible for addingα2,3-linked sialic acid to substrates and generating glycan structures.We found that the expression of ST3GAL6 was upregulated in the brains of mice with HE and in astrocytes after ammonia induction,and the expression levels of α2,3-sialylated glycans and autophagy-related proteins microtubule-associated protein light chain 3(LC3)and Beclin-1 were upregulated in ammonia-induced astrocytes.These findings suggest that ST3GAL6 is related to autophagy in HE.Therefore,we aimed to determine the regulatory relationship between ST3GAL6 and autophagy.We found that silencing ST3GAL6 and blocking or degrading α2,3-sialylated glycans by way of Maackia amurensis lectin-II(MAL-II)and neuraminidase can inhibit autophagy.In addition,silencing the expression of ST3GAL6 can downregulate the expression of heat shock proteinβ8(HSPB8)and Bcl2-associated athanogene 3(BAG3).Notably,the overexpression of HSPB8 partially restored the reduced autophagy levels caused by silencing ST3GAL6 expression.Our results indicate that ST3GAL6 regulates autophagy through the HSPB8-BAG3 complex.展开更多
目的探讨轴突型腓骨肌萎缩症2L型(axonal Charcot-Marie-Tooth disease type 2L,CMT2L)致病基因小分子热休克蛋白HSPB8(smallheatshockproteinHSPB8,HSPB8)的K141N突变导致细胞内聚集物形成的可能机理。方法建立pEGFPN1-HSPB8、pEGFPN1-...目的探讨轴突型腓骨肌萎缩症2L型(axonal Charcot-Marie-Tooth disease type 2L,CMT2L)致病基因小分子热休克蛋白HSPB8(smallheatshockproteinHSPB8,HSPB8)的K141N突变导致细胞内聚集物形成的可能机理。方法建立pEGFPN1-HSPB8、pEGFPN1-K141NHSPB8瞬时表达细胞模型,并进行EGFP-K141NHSPB8与小分子热休克蛋白HSPB1(smallheatshockproteinHSPB1,HSPB1)、神经丝轻链(neurofilamentlightchain,NEFL)的免疫荧光共定位分析,观察EGFP-K141NHSPB8在不同内源性表达细胞系的聚集物形成情况,采用t检验和单因素方差分析的统计学方法分析聚集物形成的可能机理。结果EGFP-K141NHSPB8形成以核周分布为主的聚集物,EGFP-K141NHSPB8与HSPB1、NEFL均存在免疫荧光共定位。EGFP-K141NHSPB8在不同内源性表达细胞系的聚集物形成百分率的差异有统计学意义。结论突变型HSPB8(K141N)形成以核周分布为主的胞内聚集物,聚集物中K141NHSPB8与HSPB1、NEFL均存在共定位。聚集物形成的可能机理包括K141NHSPB8多肽链构象发生改变后不能维持稳态而出现自身异常聚集;与家族内其他成员特别是HSPB1结合成异常的异源多聚体,在胞内形成不可溶性大分子后产生聚集。展开更多
Heat shock protein family B(small)member 8(HSPB8)is a 22 kDa ubiquitously expressed protein belonging to the family of small heat shock proteins.HSPB8 is involved in various cellular mechanisms mainly related to prote...Heat shock protein family B(small)member 8(HSPB8)is a 22 kDa ubiquitously expressed protein belonging to the family of small heat shock proteins.HSPB8 is involved in various cellular mechanisms mainly related to proteotoxic stress response and in other processes such as inflammation,cell division,and migration.HSPB8 binds misfolded clients to prevent their aggregation by assisting protein refolding or degradation through chaperone-assisted selective autophagy.In line with this function,the pro-degradative activity of HSPB8 has been found protective in several neurodegenerative and neuromuscular diseases characterized by protein misfolding and aggregation.In cancer,HSPB8 has a dual role being capable of exerting either a pro-or an anti-tumoral activity depending on the pathways and factors expressed by the model of cancer under investigation.Moreover,HSPB8 exerts a protective function in different diseases by modulating the inflammatory response,which characterizes not only neurodegenerative diseases,but also other chronic or acute conditions affecting the nervous system,such as multiple sclerosis and intracerebellar hemorrhage.Of note,HSPB8 modulation may represent a therapeutic approach in other neurological conditions that develop as a secondary consequence of other diseases.This is the case of cognitive impairment related to diabetes mellitus,in which HSPB8 exerts a protective activity by assuring mitochondrial homeostasis.This review aims to summarize the diverse and multiple functions of HSPB8 in different pathological conditions,focusing on the beneficial effects of its modulation.Drug-based and alternative therapeutic approaches targeting HSPB8 and its regulated pathways will be discussed,emphasizing how new strategies for cell and tissue-specific delivery represent an avenue to advance in disease treatments.展开更多
目的分析1个远端型遗传性运动神经病(distal hereditary motor neuropathy,dHMN)家系临床特征和基因变异特点。方法收集该家系先证者及其他成员的临床资料,对先证者进行神经电生理检查、肌肉活检病理检查和全外显子测序检查。结果该家...目的分析1个远端型遗传性运动神经病(distal hereditary motor neuropathy,dHMN)家系临床特征和基因变异特点。方法收集该家系先证者及其他成员的临床资料,对先证者进行神经电生理检查、肌肉活检病理检查和全外显子测序检查。结果该家系主要表现为远端型肌无力,先证者电生理提示远端型运动神经病,不伴感觉神经受累,肌肉病理提示神经源性肌萎缩,基因检测发现HSPB8基因第2外显子存在c.421A>G(p.K141E)杂合变异,为该基因的热点突变。结论HSPB8基因变异相关dHMN2A在国内尚未见报道,p.K141E为其致病性变异,本研究结果丰富了国内dHMN突变谱系。展开更多
目的探讨低糖刺激下小鼠海马神经元热休克蛋白B8(heat shock protein beta-8,HSPB8)和自噬的改变,及HSPB8对自噬的调控作用。方法 HT-22(小鼠海马神经元细胞株)细胞在葡萄糖浓度为2.5和5mmol·L^(-1)DMEM培养基中培养1h后,采用Weste...目的探讨低糖刺激下小鼠海马神经元热休克蛋白B8(heat shock protein beta-8,HSPB8)和自噬的改变,及HSPB8对自噬的调控作用。方法 HT-22(小鼠海马神经元细胞株)细胞在葡萄糖浓度为2.5和5mmol·L^(-1)DMEM培养基中培养1h后,采用Western blot法检HSPB8,Bcl-2相关永生化基因3(BCL2-Associated Athanogene 3,BAG3)、自噬相关蛋白Beclin-1和微管相关蛋白1-轻链3(microtubule-associated protein 1 light chain 3,LC3)的表达变化;GFP-LC3融合蛋白示踪法观察HT-22细胞低糖(2.5mmol·L^(-1))刺激下的自噬水平;使HT-22细胞过表达HSPB8蛋白后低糖(2.5mmol·L^(-1))刺激1h,Western blot法检测HSPB8,BAG3,LC3-Ⅱ,Beclin-1蛋白表达变化。结果 Western blot结果表明,HT-22细胞低糖(5mmol·L^(-1))刺激1h,HSPB8,BAG3,Beclin-1的表达水平均升高(P均<0.05),而LC3-Ⅱ表达水平无明显变化(P>0.05);低糖(2.5mmol·L^(-1))刺激1h,HSPB8,BAG3,LC3-Ⅱ,Beclin-1表达水平均上调(P<0.05或<0.01);GFP-LC3融合蛋白示踪法显示低糖(2.5mmol·L^(-1))刺激后HT-22细胞绿色荧光斑点增多(P<0.01);过表达HSPB8后低糖(2.5mmol·L^(-1))刺激1h,BAG3,LC3-Ⅱ,Beclin-1表达水平上调(P<0.05或<0.01)。结论小鼠海马神经元在低糖刺激下,HSPB8,BAG3及自噬水平均升高,HSPB8可以促进自噬的发生。展开更多
基金supported by the National Natural Science Foundation of China(No.82370592)the Discipline Construction Project of the Health System in Pudong New Area(No.PWZbr2022-15)the Pudong New Area Special Fund for Livelihood Research Project of Science and Technology Development Fund(No.PKJ2021-Y12),China.
文摘End-stage liver diseases,such as cirrhosis and liver cancer caused by hepatitis B,are often combined with hepatic encephalopathy(HE);ammonia poisoning is posited as one of its main pathogenesis mechanisms.Ammonia is closely related to autophagy,but the molecular mechanism of ammonia’s regulatory effect on autophagy in HE remains unclear.Sialylation is an essential form of glycosylation.In the nervous system,abnormal sialylation affects various physiological processes,such as neural development and synapse formation.ST3 β-galactoside α2,3-sialyltransferase 6(ST3GAL6)is one of the significant glycosyltransferases responsible for addingα2,3-linked sialic acid to substrates and generating glycan structures.We found that the expression of ST3GAL6 was upregulated in the brains of mice with HE and in astrocytes after ammonia induction,and the expression levels of α2,3-sialylated glycans and autophagy-related proteins microtubule-associated protein light chain 3(LC3)and Beclin-1 were upregulated in ammonia-induced astrocytes.These findings suggest that ST3GAL6 is related to autophagy in HE.Therefore,we aimed to determine the regulatory relationship between ST3GAL6 and autophagy.We found that silencing ST3GAL6 and blocking or degrading α2,3-sialylated glycans by way of Maackia amurensis lectin-II(MAL-II)and neuraminidase can inhibit autophagy.In addition,silencing the expression of ST3GAL6 can downregulate the expression of heat shock proteinβ8(HSPB8)and Bcl2-associated athanogene 3(BAG3).Notably,the overexpression of HSPB8 partially restored the reduced autophagy levels caused by silencing ST3GAL6 expression.Our results indicate that ST3GAL6 regulates autophagy through the HSPB8-BAG3 complex.
文摘目的探讨轴突型腓骨肌萎缩症2L型(axonal Charcot-Marie-Tooth disease type 2L,CMT2L)致病基因小分子热休克蛋白HSPB8(smallheatshockproteinHSPB8,HSPB8)的K141N突变导致细胞内聚集物形成的可能机理。方法建立pEGFPN1-HSPB8、pEGFPN1-K141NHSPB8瞬时表达细胞模型,并进行EGFP-K141NHSPB8与小分子热休克蛋白HSPB1(smallheatshockproteinHSPB1,HSPB1)、神经丝轻链(neurofilamentlightchain,NEFL)的免疫荧光共定位分析,观察EGFP-K141NHSPB8在不同内源性表达细胞系的聚集物形成情况,采用t检验和单因素方差分析的统计学方法分析聚集物形成的可能机理。结果EGFP-K141NHSPB8形成以核周分布为主的聚集物,EGFP-K141NHSPB8与HSPB1、NEFL均存在免疫荧光共定位。EGFP-K141NHSPB8在不同内源性表达细胞系的聚集物形成百分率的差异有统计学意义。结论突变型HSPB8(K141N)形成以核周分布为主的胞内聚集物,聚集物中K141NHSPB8与HSPB1、NEFL均存在共定位。聚集物形成的可能机理包括K141NHSPB8多肽链构象发生改变后不能维持稳态而出现自身异常聚集;与家族内其他成员特别是HSPB1结合成异常的异源多聚体,在胞内形成不可溶性大分子后产生聚集。
基金supported by:Fondazione Telethon-Italy(No.GGP19128 to AP)Fondazione Cariplo-Italy(No.2021-1544 to RC)+14 种基金Fondazione Italiana di Ricerca per la Sclerosi Laterale Amiotrofica(AriSLA)-Italy(No.MLOpathy to APTarget-RAN to AP)Association Française contre les Myopathies-France(AFM Telethon No.23236 to AP)Kennedy’s Disease Association-USA(2018 grant to RC2020 grant to MG)Ministero dell’Universitàe della Ricerca(MIUR)-Italy(PRIN-Progetti di ricerca di interesse nazionale(No.2017F2A2C5 to APNo.2022EFLFL8 to APNo.2020PBS5MJ to VCNo.2022KSJZF5 to VC)PRIN-Progetti di ricerca di interesse nazionale-bando 2022,PNRR finanziato dall’Unione europea-Next Generation EU,componente M4C2,investimento 1.1(No.P2022B5J32 to RC and No.P20225R4Y5 to VC)CN3:RNA-Codice Proposta:CN_00000041Tematica Sviluppo di terapia genica e farmaci con tecnologia a RNA(Centro Nazionale di Ricerca-CN3 National Center for Gene Therapy and Drugs based on RNA Technology to AP)Progetto Dipartimenti di Eccellenza(to DiSFeB)Ministero della Salute,Agenzia Italiana del Farmaco(AIFA)-Italy(Co_ALS to AP)Universitàdegli Studi di Milano(piano di sviluppo della ricerca(PSR)UNIMI-linea B(to RC and BT).
文摘Heat shock protein family B(small)member 8(HSPB8)is a 22 kDa ubiquitously expressed protein belonging to the family of small heat shock proteins.HSPB8 is involved in various cellular mechanisms mainly related to proteotoxic stress response and in other processes such as inflammation,cell division,and migration.HSPB8 binds misfolded clients to prevent their aggregation by assisting protein refolding or degradation through chaperone-assisted selective autophagy.In line with this function,the pro-degradative activity of HSPB8 has been found protective in several neurodegenerative and neuromuscular diseases characterized by protein misfolding and aggregation.In cancer,HSPB8 has a dual role being capable of exerting either a pro-or an anti-tumoral activity depending on the pathways and factors expressed by the model of cancer under investigation.Moreover,HSPB8 exerts a protective function in different diseases by modulating the inflammatory response,which characterizes not only neurodegenerative diseases,but also other chronic or acute conditions affecting the nervous system,such as multiple sclerosis and intracerebellar hemorrhage.Of note,HSPB8 modulation may represent a therapeutic approach in other neurological conditions that develop as a secondary consequence of other diseases.This is the case of cognitive impairment related to diabetes mellitus,in which HSPB8 exerts a protective activity by assuring mitochondrial homeostasis.This review aims to summarize the diverse and multiple functions of HSPB8 in different pathological conditions,focusing on the beneficial effects of its modulation.Drug-based and alternative therapeutic approaches targeting HSPB8 and its regulated pathways will be discussed,emphasizing how new strategies for cell and tissue-specific delivery represent an avenue to advance in disease treatments.
文摘目的分析1个远端型遗传性运动神经病(distal hereditary motor neuropathy,dHMN)家系临床特征和基因变异特点。方法收集该家系先证者及其他成员的临床资料,对先证者进行神经电生理检查、肌肉活检病理检查和全外显子测序检查。结果该家系主要表现为远端型肌无力,先证者电生理提示远端型运动神经病,不伴感觉神经受累,肌肉病理提示神经源性肌萎缩,基因检测发现HSPB8基因第2外显子存在c.421A>G(p.K141E)杂合变异,为该基因的热点突变。结论HSPB8基因变异相关dHMN2A在国内尚未见报道,p.K141E为其致病性变异,本研究结果丰富了国内dHMN突变谱系。
