OBJECTIVE To investigate the autophagic effect of the compounds from the Chinese medicinal herbs,Radix polygalae as a potential neuroprotective agent that enhances the clearance of mutant Huntingtin andα-synuclein in...OBJECTIVE To investigate the autophagic effect of the compounds from the Chinese medicinal herbs,Radix polygalae as a potential neuroprotective agent that enhances the clearance of mutant Huntingtin andα-synuclein in PC-12 cells.METHODS Radix polygalae was extracted with 75%ethanol using refluxing method,and its quality was assayed by UHPLC-TOF-MS.The autophagic effect of Radix polygalae extract,and its major components including polygalacic acid,senegenin and onjisaponin B were investigated using the green fluorescent protein-light chain 3(GFP-LC3)autophagy detection and Western blot platforms for detecting the autophagic markers,GFP-LC3 puncta formation and LC3Ⅱ expression.The degradation of A53Tα-synuclein and the inhibition of α-synuclein oligo merization related to the Parkinson disease were assayed using Western blot and flow cytometer analysis,respectively.While the cytotoxicity and the degradation of the mutant Huntingtin associated with the Huntingtin disease were investigated using MTT method and flow cytometer analysis.RESULTS Radix polygalae ethanol extract and onjisaponin B improved the GFP-LC3 puncta formation and expression of LC3Ⅱ with time and dose manner,and this induction was activated via AMPK-m TOR and Atg 7 gene pathway.Furthermore,the clearance ofα-synuclein and mutant Huntingtin was enhanced via autophagy induction with the treatment of Radix polygalae ethanol extract and onjisaponin B.CONCLUSION Findings in the current study provide detailed insights into the protective mechanism of a novel autophagy inducer,onjisaponin B,which is valuable for further investigation as a new candidate agent for modulating neurodegenerative disorders through the reduction of toxicity and clearance of mutant proteins in the cellular level.展开更多
Huntington’s disease is a neurodegenerative disease caused by the expansion mutation of a cytosine-adenine-guanine triplet in the exon 1 of the HTT gene which is responsible for the production of the huntingtin (Htt)...Huntington’s disease is a neurodegenerative disease caused by the expansion mutation of a cytosine-adenine-guanine triplet in the exon 1 of the HTT gene which is responsible for the production of the huntingtin (Htt) protein. In physiological conditions, Htt is involved in many cellular processes such as cell signaling, transcriptional regulation, energy metabolism regulation, DNA maintenance, axonal trafficking, and antiapoptotic activity. When the genetic alteration is present, the production of a mutant version of Htt (mHtt) occurs, which is characterized by a plethora of pathogenic activities that, finally, lead to cell death. Among all the cells in which mHtt exerts its dangerous activity, the GABAergic Medium Spiny Neurons seem to be the most affected by the mHtt-induced excitotoxicity both in the cortex and in the striatum. However, as the neurodegeneration proceeds ahead the neuronal loss grows also in other brain areas such as the cerebellum, hypothalamus, thalamus, subthalamic nucleus, globus pallidus, and substantia nigra, determining the variety of symptoms that characterize Huntington’s disease. From a clinical point of view, Huntington’s disease is characterized by a wide spectrum of symptoms spanning from motor impairment to cognitive disorders and dementia. Huntington’s disease shows a prevalence of around 3.92 cases every 100,000 worldwide and an incidence of 0.48 new cases every 100,000/year. To date, there is no available cure for Huntington’s disease. Several treatments have been developed so far, aiming to reduce the severity of one or more symptoms to slow down the inexorable decline caused by the disease. In this context, the search for reliable strategies to target the different aspects of Huntington’s disease become of the utmost interest. In recent years, a variety of studies demonstrated the detrimental role of neuronal loss in Huntington’s disease condition highlighting how the replacement of lost cells would be a reasonable strategy to overcome the neurodegeneration. In this view, numerous have been the attempts in several preclinical models of Huntington’s disease to evaluate the feasibility of invasive and non-invasive approaches. Thus, the aim of this review is to offer an overview of the most appealing approaches spanning from stem cell-based cell therapy to extracellular vesicles such as exosomes in light of promoting neurogenesis, discussing the results obtained so far, their limits and the future perspectives regarding the neural regeneration in the context of Huntington’s disease.展开更多
Huntington's disease(HD) is a deadly neurodegenerative disease with abnormal expansion of CAG repeats in the huntingtin gene. Mutant Huntingtin protein(m HTT) forms abnormal aggregates and intranuclear inclusions ...Huntington's disease(HD) is a deadly neurodegenerative disease with abnormal expansion of CAG repeats in the huntingtin gene. Mutant Huntingtin protein(m HTT) forms abnormal aggregates and intranuclear inclusions in specific neurons, resulting in cell death. Here,we tested the ability of a natural heat-shock protein 90 inhibitor, Gedunin, to degrade transfected m HTT in Neuro-2 a cells and endogenous m HTT aggregates and intranuclear inclusions in both fibroblasts from HD patients and neurons derived from induced pluripotent stem cells from patients. Our data showed that Gedunin treatment degraded transfected m HTT in Neuro-2 a cells, endogenous m HTT aggregates and intranuclear inclusions in fibroblasts from HD patients, and in neurons derived from induced pluripotent stem cells from patients in a dose-and time-dependent manner, and its activity depended on the proteasomal pathway rather than the autophagy route. These findings also showed that although Gedunin degraded abnormal m HTT aggregates and intranuclear inclusions in cells from HD patient, it did not affect normal cells, thus providing a new perspective for using Gedunin to treat HD.展开更多
Background:The administration of certain cannabinoids provides neuroprotection in models of neurodegenerative diseases by acting through various cellular and molecular mechanisms.Many cannabinoid actions in the nervou...Background:The administration of certain cannabinoids provides neuroprotection in models of neurodegenerative diseases by acting through various cellular and molecular mechanisms.Many cannabinoid actions in the nervous system are mediated by CB1 receptors,which can elicit psychotropic effects,but other targets devoid of psychotropic activity,including CB2 and nuclear PPARγreceptors,can also be the target of specific cannabinoids.Methods:We investigated the pro-neurogenic potential of the synthetic cannabigerol derivative,VCE-003.2,in striatal neurodegeneration by using adeno-associated viral expression of mutant huntingtin in vivo and mouse embryonic stem cell differentiation in vitro.Results:Oral administration of VCE-003.2 protected striatal medium spiny neurons from mutant huntingtin-induced damage,attenuated neuroinflammation and improved motor performance.VCE-003.2 bioavailability was characterized and the potential undesired side effects were evaluated by analyzing hepatotoxicity after chronic treatment.VCE-003.2 promoted subventricular zone progenitor mobilization,increased doublecortin-positive migrating neuroblasts towards the injured area,and enhanced effective neurogenesis.Moreover,we demonstrated the proneurogenic activity of VCE-003.2 in embryonic stem cells.VCE-003.2 was able to increase neuroblast formation and striatal-like CTIP2-mediated neurogenesis.Conclusions:The cannabigerol derivative VCE-003.2 improves subventricular zone-derived neurogenesis in response to mutant huntingtin-induced neurodegeneration,and is neuroprotective by oral administration.展开更多
Huntington's disease(HD) is caused by abnormal CAG repeat expansion in the 5′-end of the Huntingtin(HTT) gene.In addition to the canonical C-terminal full-length huntingtin(htt) nuclear export signal,a cytoplasmi...Huntington's disease(HD) is caused by abnormal CAG repeat expansion in the 5′-end of the Huntingtin(HTT) gene.In addition to the canonical C-terminal full-length huntingtin(htt) nuclear export signal,a cytoplasmic localization-related domain(CLRD) in the N-terminus of htt has recently been reported.Here,we analyzed this domain by introducing deletion and substitution mutations in a truncated N-terminal htt protein and subsequently monitored htt expression,aggregation and subcellular localization by immunocytochemistry and Western blot analysis.We demonstrated that Htt4-17 was the essential sequence for htt cytoplasmic localization.We also found that the subcellular distribution of htt was altered when Htt1-17 was mutated to contain amino acids of different charges,suggesting a structural requirement of Htt1-17 for the cytoplasmic localization of htt. Deletion of the first three amino acids did not affect its association with mitochondria.We observed that defective cytoplasmic localization resulted in a reduction of total htt aggregates and increased nuclear aggregates,indicating that the subcellular distribution of the protein might influence the aggregation process.These studies provide new insight into the molecular mechanism of htt aggregation in HD.展开更多
We reviewed recent major clinical trials with investigational drugs for the treatment of subjects with neurodegenerative diseases caused by inheritance of gene mutations or associated with genetic risk factors.Specifi...We reviewed recent major clinical trials with investigational drugs for the treatment of subjects with neurodegenerative diseases caused by inheritance of gene mutations or associated with genetic risk factors.Specifically,we discussed randomized clinical trials in subjects with Alzheimer's disease,Huntington's disease and amyotrophic lateral sclerosis bearing pathogenic gene mutations,and glucocerebrosidase-associated Parkinson's disease.Learning potential lessons to improve future therapeutic approaches is the aim of this review.Two long-term,controlled trials on three anti-β-amyloid monoclonal antibodies(solanezumab,gantenerumab and crenezumab)in subjects carrying Alzheimer's disease-linked mutated genes encoding for amyloid precursor protein or presenilin 1 or presenilin 2 failed to show cognitive or functional benefits.A major trial on tominersen,an antisense oligonucleotide designed to reduce the production of the huntingtin protein in subjects with Huntington's disease,was prematurely interrupted because the drug failed to show higher efficacy than placebo and,at highest doses,led to worsened outcomes.A 28-week trial of tofersen,an antisense oligonucleotide for superoxide dismutase 1 in patients with amyotrophic lateral sclerosis with superoxide dismutase 1 gene mutations failed to show significant beneficial effects but the 1-year open label extension of this study indicated better clinical and functional outcomes in the group with early tofersen therapy.A trial of venglustat,a potent and brain-penetrant glucosylceramide synthase inhibitor,in Parkinson's disease subjects with heterozygous glucocerebrosidase gene mutations revealed worsened clinical and cognitive performance of patients on the enzyme inhibitor compared to placebo.We concluded that clinical trials in neurodegenerative diseases with a genetic basis should test monoclonal antibodies,antisense oligonucleotides or gene editing directed against the mutated enzyme or the mutated substrate without dramatically affecting physiological wild-type variants.展开更多
基金supported by Macao Foundation(Project code:0212)FDCT grant from the Science and Technology Development Fund of Macao(Project code:076/2011/A3)
文摘OBJECTIVE To investigate the autophagic effect of the compounds from the Chinese medicinal herbs,Radix polygalae as a potential neuroprotective agent that enhances the clearance of mutant Huntingtin andα-synuclein in PC-12 cells.METHODS Radix polygalae was extracted with 75%ethanol using refluxing method,and its quality was assayed by UHPLC-TOF-MS.The autophagic effect of Radix polygalae extract,and its major components including polygalacic acid,senegenin and onjisaponin B were investigated using the green fluorescent protein-light chain 3(GFP-LC3)autophagy detection and Western blot platforms for detecting the autophagic markers,GFP-LC3 puncta formation and LC3Ⅱ expression.The degradation of A53Tα-synuclein and the inhibition of α-synuclein oligo merization related to the Parkinson disease were assayed using Western blot and flow cytometer analysis,respectively.While the cytotoxicity and the degradation of the mutant Huntingtin associated with the Huntingtin disease were investigated using MTT method and flow cytometer analysis.RESULTS Radix polygalae ethanol extract and onjisaponin B improved the GFP-LC3 puncta formation and expression of LC3Ⅱ with time and dose manner,and this induction was activated via AMPK-m TOR and Atg 7 gene pathway.Furthermore,the clearance ofα-synuclein and mutant Huntingtin was enhanced via autophagy induction with the treatment of Radix polygalae ethanol extract and onjisaponin B.CONCLUSION Findings in the current study provide detailed insights into the protective mechanism of a novel autophagy inducer,onjisaponin B,which is valuable for further investigation as a new candidate agent for modulating neurodegenerative disorders through the reduction of toxicity and clearance of mutant proteins in the cellular level.
文摘Huntington’s disease is a neurodegenerative disease caused by the expansion mutation of a cytosine-adenine-guanine triplet in the exon 1 of the HTT gene which is responsible for the production of the huntingtin (Htt) protein. In physiological conditions, Htt is involved in many cellular processes such as cell signaling, transcriptional regulation, energy metabolism regulation, DNA maintenance, axonal trafficking, and antiapoptotic activity. When the genetic alteration is present, the production of a mutant version of Htt (mHtt) occurs, which is characterized by a plethora of pathogenic activities that, finally, lead to cell death. Among all the cells in which mHtt exerts its dangerous activity, the GABAergic Medium Spiny Neurons seem to be the most affected by the mHtt-induced excitotoxicity both in the cortex and in the striatum. However, as the neurodegeneration proceeds ahead the neuronal loss grows also in other brain areas such as the cerebellum, hypothalamus, thalamus, subthalamic nucleus, globus pallidus, and substantia nigra, determining the variety of symptoms that characterize Huntington’s disease. From a clinical point of view, Huntington’s disease is characterized by a wide spectrum of symptoms spanning from motor impairment to cognitive disorders and dementia. Huntington’s disease shows a prevalence of around 3.92 cases every 100,000 worldwide and an incidence of 0.48 new cases every 100,000/year. To date, there is no available cure for Huntington’s disease. Several treatments have been developed so far, aiming to reduce the severity of one or more symptoms to slow down the inexorable decline caused by the disease. In this context, the search for reliable strategies to target the different aspects of Huntington’s disease become of the utmost interest. In recent years, a variety of studies demonstrated the detrimental role of neuronal loss in Huntington’s disease condition highlighting how the replacement of lost cells would be a reasonable strategy to overcome the neurodegeneration. In this view, numerous have been the attempts in several preclinical models of Huntington’s disease to evaluate the feasibility of invasive and non-invasive approaches. Thus, the aim of this review is to offer an overview of the most appealing approaches spanning from stem cell-based cell therapy to extracellular vesicles such as exosomes in light of promoting neurogenesis, discussing the results obtained so far, their limits and the future perspectives regarding the neural regeneration in the context of Huntington’s disease.
基金supported by the National Key Research and Development Program of China (2018YFA0108004)the National Natural Science Foundation of China (81271259)
文摘Huntington's disease(HD) is a deadly neurodegenerative disease with abnormal expansion of CAG repeats in the huntingtin gene. Mutant Huntingtin protein(m HTT) forms abnormal aggregates and intranuclear inclusions in specific neurons, resulting in cell death. Here,we tested the ability of a natural heat-shock protein 90 inhibitor, Gedunin, to degrade transfected m HTT in Neuro-2 a cells and endogenous m HTT aggregates and intranuclear inclusions in both fibroblasts from HD patients and neurons derived from induced pluripotent stem cells from patients. Our data showed that Gedunin treatment degraded transfected m HTT in Neuro-2 a cells, endogenous m HTT aggregates and intranuclear inclusions in fibroblasts from HD patients, and in neurons derived from induced pluripotent stem cells from patients in a dose-and time-dependent manner, and its activity depended on the proteasomal pathway rather than the autophagy route. These findings also showed that although Gedunin degraded abnormal m HTT aggregates and intranuclear inclusions in cells from HD patient, it did not affect normal cells, thus providing a new perspective for using Gedunin to treat HD.
基金This work was supported by the MINECO grant RTC-2015-3364 to EM and IGR cofounded by the European Development Regional Fund in the Framework of the Operative Program“Reinforcement of research,technological development and innovation”IGR was also supported by grant PI15-00310 and PI18-00941 cofinanced by the European Development Regional Fund“A way to achieve Europe”+1 种基金EM by the MINECO grant SAF2017-87701-RJA and JPL were supported by FPI and FPU program fellowship(Ministerio de Educación,Cultura y Deporte)and DGR by Fundación Tatiana de Guzmán el Bueno.BP is a predoctoral fellow supported by the i-PFIS program,Instituto de Salud CarlosⅢ(IFI15/00022,European Social Fund“Investing in your future”).
文摘Background:The administration of certain cannabinoids provides neuroprotection in models of neurodegenerative diseases by acting through various cellular and molecular mechanisms.Many cannabinoid actions in the nervous system are mediated by CB1 receptors,which can elicit psychotropic effects,but other targets devoid of psychotropic activity,including CB2 and nuclear PPARγreceptors,can also be the target of specific cannabinoids.Methods:We investigated the pro-neurogenic potential of the synthetic cannabigerol derivative,VCE-003.2,in striatal neurodegeneration by using adeno-associated viral expression of mutant huntingtin in vivo and mouse embryonic stem cell differentiation in vitro.Results:Oral administration of VCE-003.2 protected striatal medium spiny neurons from mutant huntingtin-induced damage,attenuated neuroinflammation and improved motor performance.VCE-003.2 bioavailability was characterized and the potential undesired side effects were evaluated by analyzing hepatotoxicity after chronic treatment.VCE-003.2 promoted subventricular zone progenitor mobilization,increased doublecortin-positive migrating neuroblasts towards the injured area,and enhanced effective neurogenesis.Moreover,we demonstrated the proneurogenic activity of VCE-003.2 in embryonic stem cells.VCE-003.2 was able to increase neuroblast formation and striatal-like CTIP2-mediated neurogenesis.Conclusions:The cannabigerol derivative VCE-003.2 improves subventricular zone-derived neurogenesis in response to mutant huntingtin-induced neurodegeneration,and is neuroprotective by oral administration.
基金supported by the National Natural Science Foundation of China(Grant Nos.30770761 and 30971000)
文摘Huntington's disease(HD) is caused by abnormal CAG repeat expansion in the 5′-end of the Huntingtin(HTT) gene.In addition to the canonical C-terminal full-length huntingtin(htt) nuclear export signal,a cytoplasmic localization-related domain(CLRD) in the N-terminus of htt has recently been reported.Here,we analyzed this domain by introducing deletion and substitution mutations in a truncated N-terminal htt protein and subsequently monitored htt expression,aggregation and subcellular localization by immunocytochemistry and Western blot analysis.We demonstrated that Htt4-17 was the essential sequence for htt cytoplasmic localization.We also found that the subcellular distribution of htt was altered when Htt1-17 was mutated to contain amino acids of different charges,suggesting a structural requirement of Htt1-17 for the cytoplasmic localization of htt. Deletion of the first three amino acids did not affect its association with mitochondria.We observed that defective cytoplasmic localization resulted in a reduction of total htt aggregates and increased nuclear aggregates,indicating that the subcellular distribution of the protein might influence the aggregation process.These studies provide new insight into the molecular mechanism of htt aggregation in HD.
文摘We reviewed recent major clinical trials with investigational drugs for the treatment of subjects with neurodegenerative diseases caused by inheritance of gene mutations or associated with genetic risk factors.Specifically,we discussed randomized clinical trials in subjects with Alzheimer's disease,Huntington's disease and amyotrophic lateral sclerosis bearing pathogenic gene mutations,and glucocerebrosidase-associated Parkinson's disease.Learning potential lessons to improve future therapeutic approaches is the aim of this review.Two long-term,controlled trials on three anti-β-amyloid monoclonal antibodies(solanezumab,gantenerumab and crenezumab)in subjects carrying Alzheimer's disease-linked mutated genes encoding for amyloid precursor protein or presenilin 1 or presenilin 2 failed to show cognitive or functional benefits.A major trial on tominersen,an antisense oligonucleotide designed to reduce the production of the huntingtin protein in subjects with Huntington's disease,was prematurely interrupted because the drug failed to show higher efficacy than placebo and,at highest doses,led to worsened outcomes.A 28-week trial of tofersen,an antisense oligonucleotide for superoxide dismutase 1 in patients with amyotrophic lateral sclerosis with superoxide dismutase 1 gene mutations failed to show significant beneficial effects but the 1-year open label extension of this study indicated better clinical and functional outcomes in the group with early tofersen therapy.A trial of venglustat,a potent and brain-penetrant glucosylceramide synthase inhibitor,in Parkinson's disease subjects with heterozygous glucocerebrosidase gene mutations revealed worsened clinical and cognitive performance of patients on the enzyme inhibitor compared to placebo.We concluded that clinical trials in neurodegenerative diseases with a genetic basis should test monoclonal antibodies,antisense oligonucleotides or gene editing directed against the mutated enzyme or the mutated substrate without dramatically affecting physiological wild-type variants.
