Neurodegenerative diseases are caused by the progressive loss of specific neurons.The exact mechanisms of action of these diseases are unknown,and many studies have focused on pathways related to abnormal accumulation...Neurodegenerative diseases are caused by the progressive loss of specific neurons.The exact mechanisms of action of these diseases are unknown,and many studies have focused on pathways related to abnormal accumulation and processing of proteins,mitochondrial dysfunction,and oxidative stress leading to apoptotic death.However,a growing body of evidence indicates that aberrant cell cycle re-entry plays a major role in the pathogenesis of neurodegeneration.The activation of the cell cycle in mature neurons could be promoted by several signaling mechanisms,including c-Jun N-terminal kinases,p38 mitogen-activated protein kinases,and mitogen-activated protein kinase/extracellular signal-regulated kinase cascades;post-translational modifications such as Tau-phosphorylation;and DNA damage response.In all these events,implicated Cdk5,a proline-directed serine/threonine protein kinase,seems to be responsible for several cellular processes in neurons including axon growth,neurotransmission,synaptic plasticity,neuronal migration,and maintenance of neuronal survival.However,under pathological conditions,Cdk5 dysregulation may lead to cell cycle re-entry in post-mitotic neurons.Thus,Cdk5 hyperactivation,by its physiologic activator p25,hyper-phosphorylates downstream substrates related to neurodegenerative diseases.This review summarizes factors such as oxidative stress,DNA damage response,signaling pathway disturbance,and Ubiquitin proteasome malfunction contributing to cell cycle re-entry in post-mitotic neurons.It also describes how all these factors are linked to a greater or lesser extent with Cdk5.Thus,it offers a global vision of the function of cell cycle-related proteins in mature neurons with a focus on Cdk5 and how this protein contributes to the development of Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis,and Huntington’s disease by cell cycle activation.展开更多
BACKGROUND Anoctamin 5(ANO5)/transmembrane protein 16E belongs to the ANO/transmembrane protein 16 anion channel family.ANOs comprise a family of plasma membrane proteins that mediate ion transport and phospholipid sc...BACKGROUND Anoctamin 5(ANO5)/transmembrane protein 16E belongs to the ANO/transmembrane protein 16 anion channel family.ANOs comprise a family of plasma membrane proteins that mediate ion transport and phospholipid scrambling and regulate other membrane proteins in numerous cell types.Previous studies have elucidated the roles and mechanisms of ANO5 activation in various cancer types.However,it remains unclear whether ANO5 acts as a plasma membrane chloride channel,and its expression and functions in gastric cancer(GC)have not been investigated.AIM To examine the role of ANO5 in the regulation of tumor progression and clinicopathological significance of its expression in GC.METHODS Knockdown experiments using ANO5 small interfering RNA were conducted in human GC cell lines,and changes in cell proliferation,cell cycle progression,apoptosis,and cellular movement were assessed.The gene expression profiles of GC cells were investigated following ANO5 silencing by microarray analysis.Immunohistochemical staining of ANO5 was performed on 195 primary tumor samples obtained from patients with GC who underwent curative gastrectomy between 2011 and 2013 at our department.RESULTS Reverse transcription-quantitative polymerase chain reaction(PCR)and western blotting demonstrated high ANO5 mRNA and protein expression,respectively,in NUGC4 and MKN45 cells.In these cells,ANO5 silencing inhibited cell proliferation and induced apoptosis.In addition,the knockdown of ANO5 inhibited G1-S phase progression,invasion,and migration.The results of the microarray analysis revealed changes in the expression levels of several cyclin-associated genes,such as CDKN1A,CDK2/4/6,CCNE2,and E2F1,in ANO5-depleted NUGC4 cells.The expression of these genes was verified using reverse transcription-quantitative PCR.Immunohistochemical staining revealed that high ANO5 expression levels were associated with a poor prognosis.Multivariate analysis identified high ANO5 expression as an independent prognostic factor for 5-year survival in patients with GC(P=0.0457).CONCLUSION ANO5 regulates the cell cycle progression by regulating the expression of cyclin-associated genes and affects the prognosis of patients with GC.These results may provide insights into the role of ANO5 as a key mediator in tumor progression and/or promising prognostic biomarker for GC.展开更多
We have previously found that long-term effects of exposure to radiofrequency electromagnetic fields in 5xFAD mice with severe late-stage Alzheimer’s disease reduced both amyloid-βdeposition and glial activation,inc...We have previously found that long-term effects of exposure to radiofrequency electromagnetic fields in 5xFAD mice with severe late-stage Alzheimer’s disease reduced both amyloid-βdeposition and glial activation,including microglia.To examine whether this therapeutic effect is due to the regulation of activated microglia,we analyzed mic roglial gene expression profiles and the existence of microglia in the brain in this study.5xFAD mice at the age of 1.5 months were assigned to sham-and radiofrequency electromagnetic fields-exposed groups and then animals were exposed to 1950 MHz radiofrequency electromagnetic fields at a specific absorption rate of 5 W/kg for 2 hours/day and 5 days/week for 6 months.We conducted behavioral tests including the object recognition and Y-maze tests and molecular and histopathological analysis of amyloid precursor protein/a myloid-beta metabolism in brain tissue.We confirmed that radiofrequency electromagnetic field exposure for 6 months ameliorated cognitive impairment and amyloid-βdeposition.The expression levels of Iba1(pan-microglial marker)and colony-stimulating factor 1 receptor(CSF1R;regulates microglial prolife ration)in the hippocampus in 5xFAD mice treated with radiofrequency electromagnetic fields were significantly reduced compared with those of the sham-exposed group.Subsequently,we analyzed the expression levels of genes related to mic rogliosis and microglial function in the radiofrequency electromagnetic fields-exposed group compared to those of a CSF1R inhibitor(PLX3397)-treated group.Both radiofrequency electromagnetic fields and PLX3397 suppressed the levels of genes related to microgliosis(Csf1r,CD68,and Ccl6)and pro-inflammatory cytokine interleukin-1β.N otably,the expression levels of genes related to mic roglial function,including Trem2,Fcgr1α,Ctss,and Spi1,were decreased after long-term radiofrequency electromagnetic field exposure,which was also observed in response to microglial suppression by PLX3397.These results showed that radiofrequency electromagnetic fields ameliorated amyloid-βpathology and cognitive impairment by suppressing amyloid-βdeposition-induced microgliosis and their key regulator,CSF1R.展开更多
Novel cyclic esters (1R, 2R, 3R, 5S, 7S, 9R, 12R)-3-(t-butyldimethylsilyl)oxy-7- methoxymethyloxy-2, 10-dimethyl-12-oxatricyclo [7.2.1.05,12] dodecane were prepared when their precursor 1 was treated with SOCl2/pyri...Novel cyclic esters (1R, 2R, 3R, 5S, 7S, 9R, 12R)-3-(t-butyldimethylsilyl)oxy-7- methoxymethyloxy-2, 10-dimethyl-12-oxatricyclo [7.2.1.05,12] dodecane were prepared when their precursor 1 was treated with SOCl2/pyridine. A plausible mechanism was hypothesized.展开更多
The crystal structure of the title compound（C19H15F3N2O2,Mr = 360.33） was determined by single-crystal X-ray diffraction.The crystal belongs to triclinic,space group P1,with a = 6.5604（7）,b = 13.9614（16）,c = 18....The crystal structure of the title compound（C19H15F3N2O2,Mr = 360.33） was determined by single-crystal X-ray diffraction.The crystal belongs to triclinic,space group P1,with a = 6.5604（7）,b = 13.9614（16）,c = 18.1790（18） ,α = 102.749（7）,β = 97.542（6）,γ = 94.355（4）°,V = 1600.5（3） 3,Z = 4,Dc = 1.495 g/cm3,λ（MoKα） = 0.71070,F（000） = 744,μ（MoKα） = 0.122 mm-1,R = 0.0434 and wR = 0.1051.A total of 7590 unique reflections were collected,of which 5429 with ｜F｜2 ≥ 2σ｜F｜2 were observed.The two cyclohexene rings in the molecule adopt boat-boat conformations with the deviations of ring atoms C（9） and C10 from the C（5）/C（6）/C（7）/C（8） plane（Ⅰ） by 1.1204（0.0023） and 1.1132（0.0023） ,respectively,whereas from the C（2）/C（3）/C（5）/C（8） plane（Ⅱ） by 1.1627（0.0022） and 1.1818（0.0021） ,respectively.In the cyclopropane and lactam rings,atoms C（11） and N（1） point towards the double bond of C（9）-C（10） and the dihedral angle between the ring plane（Ⅲ） containing C（1）,C（2）,C（3） and C（4） and plane（IV） consisting of C（6）,C（7） and C（11） is 55.76（0.07）°.The dihedral angles between planes Ⅳ and Ⅰ and Ⅱ and Ⅲare 63.58（0.07）° and 58.10（0.06）°,respectively.The dihedral angle between the benzene ring C（13）～ C（18） and plane Ⅳ is 42.41（0.06）°.展开更多
基金supported by the Spanish Ministry of Industry and Competitiveness[Grant BFU2016-80006-P]The Andalusian Regional Government[Group BIO-216]the FEDER-Andalusian programme 2014-2020[1262530-R].
文摘Neurodegenerative diseases are caused by the progressive loss of specific neurons.The exact mechanisms of action of these diseases are unknown,and many studies have focused on pathways related to abnormal accumulation and processing of proteins,mitochondrial dysfunction,and oxidative stress leading to apoptotic death.However,a growing body of evidence indicates that aberrant cell cycle re-entry plays a major role in the pathogenesis of neurodegeneration.The activation of the cell cycle in mature neurons could be promoted by several signaling mechanisms,including c-Jun N-terminal kinases,p38 mitogen-activated protein kinases,and mitogen-activated protein kinase/extracellular signal-regulated kinase cascades;post-translational modifications such as Tau-phosphorylation;and DNA damage response.In all these events,implicated Cdk5,a proline-directed serine/threonine protein kinase,seems to be responsible for several cellular processes in neurons including axon growth,neurotransmission,synaptic plasticity,neuronal migration,and maintenance of neuronal survival.However,under pathological conditions,Cdk5 dysregulation may lead to cell cycle re-entry in post-mitotic neurons.Thus,Cdk5 hyperactivation,by its physiologic activator p25,hyper-phosphorylates downstream substrates related to neurodegenerative diseases.This review summarizes factors such as oxidative stress,DNA damage response,signaling pathway disturbance,and Ubiquitin proteasome malfunction contributing to cell cycle re-entry in post-mitotic neurons.It also describes how all these factors are linked to a greater or lesser extent with Cdk5.Thus,it offers a global vision of the function of cell cycle-related proteins in mature neurons with a focus on Cdk5 and how this protein contributes to the development of Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis,and Huntington’s disease by cell cycle activation.
基金Supported by Japan Society for the Promotion of Science,No.21K08689,No.21K16456,No.20K09016,No.20K09084,No.19K09202 and No.19K09182.
文摘BACKGROUND Anoctamin 5(ANO5)/transmembrane protein 16E belongs to the ANO/transmembrane protein 16 anion channel family.ANOs comprise a family of plasma membrane proteins that mediate ion transport and phospholipid scrambling and regulate other membrane proteins in numerous cell types.Previous studies have elucidated the roles and mechanisms of ANO5 activation in various cancer types.However,it remains unclear whether ANO5 acts as a plasma membrane chloride channel,and its expression and functions in gastric cancer(GC)have not been investigated.AIM To examine the role of ANO5 in the regulation of tumor progression and clinicopathological significance of its expression in GC.METHODS Knockdown experiments using ANO5 small interfering RNA were conducted in human GC cell lines,and changes in cell proliferation,cell cycle progression,apoptosis,and cellular movement were assessed.The gene expression profiles of GC cells were investigated following ANO5 silencing by microarray analysis.Immunohistochemical staining of ANO5 was performed on 195 primary tumor samples obtained from patients with GC who underwent curative gastrectomy between 2011 and 2013 at our department.RESULTS Reverse transcription-quantitative polymerase chain reaction(PCR)and western blotting demonstrated high ANO5 mRNA and protein expression,respectively,in NUGC4 and MKN45 cells.In these cells,ANO5 silencing inhibited cell proliferation and induced apoptosis.In addition,the knockdown of ANO5 inhibited G1-S phase progression,invasion,and migration.The results of the microarray analysis revealed changes in the expression levels of several cyclin-associated genes,such as CDKN1A,CDK2/4/6,CCNE2,and E2F1,in ANO5-depleted NUGC4 cells.The expression of these genes was verified using reverse transcription-quantitative PCR.Immunohistochemical staining revealed that high ANO5 expression levels were associated with a poor prognosis.Multivariate analysis identified high ANO5 expression as an independent prognostic factor for 5-year survival in patients with GC(P=0.0457).CONCLUSION ANO5 regulates the cell cycle progression by regulating the expression of cyclin-associated genes and affects the prognosis of patients with GC.These results may provide insights into the role of ANO5 as a key mediator in tumor progression and/or promising prognostic biomarker for GC.
基金Institute of Information&Communications Technology Planning&Evaluation(IITP)grant funded by Korea government(MSIT),Nos.2017-0-00961 and 2019-0-00102(to HDC)。
文摘We have previously found that long-term effects of exposure to radiofrequency electromagnetic fields in 5xFAD mice with severe late-stage Alzheimer’s disease reduced both amyloid-βdeposition and glial activation,including microglia.To examine whether this therapeutic effect is due to the regulation of activated microglia,we analyzed mic roglial gene expression profiles and the existence of microglia in the brain in this study.5xFAD mice at the age of 1.5 months were assigned to sham-and radiofrequency electromagnetic fields-exposed groups and then animals were exposed to 1950 MHz radiofrequency electromagnetic fields at a specific absorption rate of 5 W/kg for 2 hours/day and 5 days/week for 6 months.We conducted behavioral tests including the object recognition and Y-maze tests and molecular and histopathological analysis of amyloid precursor protein/a myloid-beta metabolism in brain tissue.We confirmed that radiofrequency electromagnetic field exposure for 6 months ameliorated cognitive impairment and amyloid-βdeposition.The expression levels of Iba1(pan-microglial marker)and colony-stimulating factor 1 receptor(CSF1R;regulates microglial prolife ration)in the hippocampus in 5xFAD mice treated with radiofrequency electromagnetic fields were significantly reduced compared with those of the sham-exposed group.Subsequently,we analyzed the expression levels of genes related to mic rogliosis and microglial function in the radiofrequency electromagnetic fields-exposed group compared to those of a CSF1R inhibitor(PLX3397)-treated group.Both radiofrequency electromagnetic fields and PLX3397 suppressed the levels of genes related to microgliosis(Csf1r,CD68,and Ccl6)and pro-inflammatory cytokine interleukin-1β.N otably,the expression levels of genes related to mic roglial function,including Trem2,Fcgr1α,Ctss,and Spi1,were decreased after long-term radiofrequency electromagnetic field exposure,which was also observed in response to microglial suppression by PLX3397.These results showed that radiofrequency electromagnetic fields ameliorated amyloid-βpathology and cognitive impairment by suppressing amyloid-βdeposition-induced microgliosis and their key regulator,CSF1R.
文摘Novel cyclic esters (1R, 2R, 3R, 5S, 7S, 9R, 12R)-3-(t-butyldimethylsilyl)oxy-7- methoxymethyloxy-2, 10-dimethyl-12-oxatricyclo [7.2.1.05,12] dodecane were prepared when their precursor 1 was treated with SOCl2/pyridine. A plausible mechanism was hypothesized.
文摘The crystal structure of the title compound（C19H15F3N2O2,Mr = 360.33） was determined by single-crystal X-ray diffraction.The crystal belongs to triclinic,space group P1,with a = 6.5604（7）,b = 13.9614（16）,c = 18.1790（18） ,α = 102.749（7）,β = 97.542（6）,γ = 94.355（4）°,V = 1600.5（3） 3,Z = 4,Dc = 1.495 g/cm3,λ（MoKα） = 0.71070,F（000） = 744,μ（MoKα） = 0.122 mm-1,R = 0.0434 and wR = 0.1051.A total of 7590 unique reflections were collected,of which 5429 with ｜F｜2 ≥ 2σ｜F｜2 were observed.The two cyclohexene rings in the molecule adopt boat-boat conformations with the deviations of ring atoms C（9） and C10 from the C（5）/C（6）/C（7）/C（8） plane（Ⅰ） by 1.1204（0.0023） and 1.1132（0.0023） ,respectively,whereas from the C（2）/C（3）/C（5）/C（8） plane（Ⅱ） by 1.1627（0.0022） and 1.1818（0.0021） ,respectively.In the cyclopropane and lactam rings,atoms C（11） and N（1） point towards the double bond of C（9）-C（10） and the dihedral angle between the ring plane（Ⅲ） containing C（1）,C（2）,C（3） and C（4） and plane（IV） consisting of C（6）,C（7） and C（11） is 55.76（0.07）°.The dihedral angles between planes Ⅳ and Ⅰ and Ⅱ and Ⅲare 63.58（0.07）° and 58.10（0.06）°,respectively.The dihedral angle between the benzene ring C（13）～ C（18） and plane Ⅳ is 42.41（0.06）°.
