Neuronal and astrocytic contributions to Huntington’s disease dissected following mutant Huntingtin (mHTT) lowering
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ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE211891 | GEO | 2022/12/15
REPOSITORIES: GEO
Similar Datasets
Project description:Huntington’s disease (HD) is caused by expanded CAG repeats in the Huntingtin gene (HTT) that results in expression of mutant HTT proteins (mHTT) with extended polyglutamine tracts in diverse cells of the body, including striatal neurons and astrocytes. The relative contributions of neurons and astrocytes to disease pathogenesis are unknown for HD and other neurodegenerative diseases. This is a critical issue to address since it has been proposed that neuronal loss in HD and other major neurodegenerative diseases is downstream of astrocytic dysfunction that drives neuronal death. Moreover, astrocyte-to-neuron conversion is considered a promising approach in HD and other neurodegenerative diseases with little reported detriment with regards to normal astrocytic physiological functions, which are varied and extensive in health and disease. Thus, astrocytes are considered both causative and also largely replaceable in neurodegeneration, and their basic contributions to disease pathophysiology relative to neurons remain undefined in vivo. We used genetically encoded and cell-specific zinc finger protein (ZFP) transcriptional repressors to lower mHTT and molecularly dissected neuronal and astrocytic influences on HD pathophysiology at molecular, cellular, and behavioral levels. We found that the major disease drivers were in fact neurons, with astrocytes displaying lesser loss of essential functions such as cholesterol metabolism that were downstream of greater neuronal dysfunction, which encompassed neuromodulation, synaptic, and intracellular signaling. We thus dissected the cell autonomous and non-cell autonomous mechanistic and causal contributions of both neurons and astrocytes to a complex neurodegenerative disease in vivo with wider implications for rescue and repair strategies.
2022-12-15 | PXD030021 | Pride
Project description:We performed cell-type specific RNAseq in astrocytes and neurons in the presence or absence of ZFP transcriptional repressors in the striatum of R6/2 mouse model of HD.
2022-12-15 | GSE189647 | GEO
Project description:Small molecule activation of a pseudoexon triggers huntingtin-lowering
| PRJNA683073 | ENA
Project description:Small molecule activation of a pseudoexon triggers huntingtin-lowering (AmpliSeq)
| PRJNA683141 | ENA
Project description:Huntington’s disease (HD) is a dominantly inherited neurodegenerative disorder caused by a CAG trinucleotide expansion in the huntingtin gene (HTT), which codes for the pathologic mutant HTT (mHTT) protein. Since normal HTT is thought to be important for brain function, we engineered zinc finger protein transcription factors (ZFP-TFs) to target the pathogenic CAG repeat and selectively lower mHTT as a therapeutic strategy. Using patient-derived fibroblasts and neurons, we demonstrate that ZFP-TFs selectively repress >99% of HD-causing alleles over a wide dose range, while preserving expression of >86% of normal alleles. Other CAG-containing genes are minimally affected, and virally delivered ZFP-TFs are active and well tolerated in HD neurons beyond 100 days in culture and at least 9 months in the mouse brain. Using three HD mouse models, we demonstrate improvements in a range of molecular, histopathological, electrophysiological, and functional endpoints. Our findings support the continued development of an allele-selective ZFP-TF for the treatment of HD.
2019-06-30 | GSE127820 | GEO
Project description:Huntington’s disease (HD) is a dominantly inherited neurodegenerative disorder caused by a CAG trinucleotide expansion in the huntingtin gene (HTT), which codes for the pathologic mutant HTT (mHTT) protein. Since normal HTT is thought to be important for brain function, we engineered zinc finger protein transcription factors (ZFP-TFs) to target the pathogenic CAG repeat and selectively lower mHTT as a therapeutic strategy. Using patient-derived fibroblasts and neurons, we demonstrate that ZFP-TFs selectively repress >99% of HD-causing alleles over a wide dose range, while preserving expression of >86% of normal alleles. Other CAG-containing genes are minimally affected, and virally delivered ZFP-TFs are active and well tolerated in HD neurons beyond 100 days in culture and at least 9 months in the mouse brain. Using three HD mouse models, we demonstrate improvements in a range of molecular, histopathological, electrophysiological, and functional endpoints. Our findings support the continued development of an allele-selective ZFP-TF for the treatment of HD.
2019-06-30 | GSE127821 | GEO
Project description:Huntington’s disease (HD) is characterized by hypomyelination as well as by neuronal loss. To assess the basis for white matter involution in HD, we generated bipotential glial progenitor cells (GPCs) from human embryonic stem cells (hESCs), derived from either huntingtin (mHTT)-mutant embryos or normal controls, and performed RNA sequence analysis to assess mHTT-dependent changes in gene expression. In hGPCs derived from 3 distinct mHTT-expressing hESC lines, a set of transcription factors associated with glial differentiation and myelin synthesis was sharply down-regulated, relative to normal hESC GPCs. In particular, NKX2.2, OLIG2, SOX10 and MYRF were all suppressed, with the consequent diminution of myelinogenesis-associated transcription. Accordingly, when mHTT-expressing hGPCs were transplanted into hypomyelinated shiverer mice, the resultant mHTT glial chimeras were hypomyelinated. The mHTT hGPCs also manifested impaired astrocytic differentiation, and developed abnormal fiber domain architecture. These data suggest that white matter involution in HD is a product of a cell-autonomous mHTT-dependent suppression of both astrocytic and oligodendrocytic differentiation by affected GPCs.
2018-11-10 | GSE105041 | GEO
Project description:Huntington’s disease (HD) is a hereditary neurodegenerative disorder caused by abnormal expansion of cytosine-adenine-guanine (CAG) trinucleotide repeats in the huntingtin gene (HTT). The resultant mutant protein is ubiquitously expressed and drives pathogenesis of HD through a toxic gain-of-function mechanism. Animal models of HD have demonstrated that reducing huntingtin protein (HTT) levels alleviates HD-associated motor and neuropathological abnormalities, confirming the importance of huntingtin-lowering as a therapeutic approach. Several therapies in development repress HTT transcription or translation, including antisense oligonucleotides, virally-delivered microRNAs, and zinc finger protein transcription factors. However, they all require invasive procedures to reach the central nervous system (CNS) and do not distribute evenly to target areas in the brain. Systemically distributed therapeutics are needed to address the CNS and peripheral dysfunctions associated with HD. Here we report the discovery of small molecule splicing modifiers that lower HTT expression by selective modulation of pre-mRNA splicing. These compounds promote the inclusion of a pseudoexon containing a premature termination codon triggering HTT mRNA degradation and a reduction of HTT protein levels in vitro and in vivo. These orally bioavailable small molecules represent a non-invasive treatment option for HD and our findings support their continued development for the treatment of HD.
2021-07-01 | GSE162812 | GEO
Project description:Small molecule activation of a pseudoexon triggers huntingtin-lowering (RNA-Seq)
| PRJNA683140 | ENA
Project description:Huntington’s disease (HD) is a hereditary neurodegenerative disorder caused by abnormal expansion of cytosine-adenine-guanine (CAG) trinucleotide repeats in the huntingtin gene (HTT). The resultant mutant protein is ubiquitously expressed and drives pathogenesis of HD through a toxic gain-of-function mechanism. Animal models of HD have demonstrated that reducing huntingtin protein (HTT) levels alleviates HD-associated motor and neuropathological abnormalities, confirming the importance of huntingtin-lowering as a therapeutic approach. Several therapies in development repress HTT transcription or translation, including antisense oligonucleotides, virally-delivered microRNAs, and zinc finger protein transcription factors. However, they all require invasive procedures to reach the central nervous system (CNS) and do not distribute evenly to target areas in the brain. Systemically distributed therapeutics are needed to address the CNS and peripheral dysfunctions associated with HD. Here we report the discovery of small molecule splicing modifiers that lower HTT expression by selective modulation of pre-mRNA splicing. These compounds promote the inclusion of a pseudoexon containing a premature termination codon triggering HTT mRNA degradation and a reduction of HTT protein levels in vitro and in vivo. These orally bioavailable small molecules represent a non-invasive treatment option for HD and our findings support their continued development for the treatment of HD.
2021-07-01 | GSE162813 | GEO