Journal of Huntington's disease最新文献

BackgroundHuntington's Disease (HD) is a hereditary neurodegenerative disorder caused by a cytosine-adenine-guanine (CAG) repeat expansion (CAG > 35) in the Huntingtin (HTT) gene. Intermediate alleles (IAs, CAG = 27-35) are generally not associated with HD. However, IA carriers with symptoms have been reported in literature.ObjectiveTo review the existing literature on IAs, in order to provide an overview of the clinical phenotype of IA carriers.MethodsPeer-reviewed articles published between 1993 and July 2024 from three databases (Embase, PubMed, and Web of Science) were included.ResultsIn case reports, a high percentage (90%) of IA carriers was reported to have symptoms (HD-related and -unrelated), or abnormalities in neuroimaging. Cohort studies also reported evidence of symptoms in IA carriers, although most cohorts did not obtain significant differences compared to controls.ConclusionBased on this review, we argue that there is not enough evidence to draw a clear conclusion on the clinical phenotype of individuals carrying an intermediate allele of the HTT gene. Literature reports symptomatic IA carriers, but reported symptoms are non-specific and common in the general population. Additionally, the quality of the data is suboptimal, due to lack of detailed symptom descriptions, the absence of differential diagnoses, a selection bias, and a considerable publication bias towards IA carriers with symptoms. More research is needed to provide a better insight into the clinical phenotype of IA carriers.

A recent retrospective analysis of Enroll HD data suggesting β-blockers slow Huntington's disease progression has triggered patient demand but requires caution. The findings rely solely on small observational subsets and are vulnerable to bias and confounding. A prior Mendelian-randomization study found no causal link between β-blockers and HD onset; instead, genetically higher blood pressure was associated with later onset, raising concern that β-blockers' BP-lowering effects could be harmful. HD patients also have lower hypertension rates, and β-blockers carry risks such as depression and bradycardia. Given their heterogeneous mechanisms, rigorous experimental and clinical trials are needed before any clinical recommendations.

Two- and three-dimensional (2D and 3D) cell models derived from human stem cells have shed light on a wide range of molecular and cellular features of Huntington's disease (HD). Here we review the use of human stem cell-derived models to explore neurodevelopmental contributions to HD. We provide a timeline of key advances made in 2D and 3D model systems, ranging from differentiated monocultures to brain-like organoids and assembloids. Models along this spectrum have advanced our understanding of various disease-associated characteristics including disease protein (huntingtin) aggregation, somatic repeat instability, transcriptional dysregulation, perturbations in neurodevelopmental staging, and neural circuitry. We highlight recent findings in brain-like organoids which, despite being a relatively recent innovation, are proving to be a promising tool with which to study aberrant neurodevelopmental features of HD. All models have their limitations, and we compare and contrast the utility and limitations of various stem cell-based methods to study HD. Finally, we speculate on future advances employing advanced computational and transcriptomic methods that will expand the power of 3D model systems for the study of HD and related neurodegenerative disorders.

In this edition of the Huntington's Disease Clinical Trials Update, we expand on the launch of the phase II/III clinical trial of SKY-0515 from Skyhawk Therapeutics and the phase I/II clinical trial of SPK-10001 from Spark Therapeutics. We also report positive topline data from uniQure's phase I/II clinical trial of AMT-130 after 36 months of follow-up. Further updates include recent developments in Roche's tominersen programme within GENERATION HD2, progress with votoplam (PTC518) in PIVOT-HD by PTC Therapeutics and developments in the collaborative PTC Therapeutics/Novartis programme. We additionally discuss regulatory developments regarding pridopidine following the negative PROOF-HD study. Finally, we provide an updated listing of all registered and ongoing clinical trials in Huntington's disease.

BackgroundComputerized cognitive training (CCT) has been found to improve cognition by altering functional activity and functional connectivity of brain networks in people with and without cognitive impairment. The effects of CCT on functional brain networks in Huntington's disease (HD) have not been comprehensively examined.ObjectiveIn our pilot trial of CCT, we aimed to explore effects of CCT on functional activity and connectivity of fronto-striatal regions during processing speed and cognitive flexibility tasks, and functional connectivity of resting-state networks in HD.MethodsSixteen participants in pre-manifest and early stages of HD were randomised to either a 12-week multi-domain CCT intervention (n = 6) or lifestyle education (n = 10). Participants completed a 1-h magnetic resonance imaging (MRI) scan at baseline and follow-up, which included task-based and resting-state functional MRI. Analyses examined changes in functional activity and connectivity of fronto-striatal regions during processing speed and cognitive flexibility task performance, as well as functional connectivity within default mode and frontoparietal resting-state networks.ResultsWhile there was evidence of benefits to in-scanner task performance, there were no significant effects on functional activity or functional connectivity of fronto-striatal regions during task performance, or resting-state functional connectivity.ConclusionCCT did not generate significant effects on functional activity or connectivity of fronto-striatal networks associated with processing speed or cognitive flexibility, or resting-state networks in HD. A larger study is required to further examine the effects of CCT on functional brain outcomes and potential moderating factors.

Huntington's disease (HD) is classically characterized as a late-onset neurodegenerative disorder of adulthood caused by CAG expansion in the HTT gene. However, mounting evidence from both human and experimental studies suggests that both wild-type and mutant huntingtin play important roles during brain development. In this review, we examine the developmental functions of huntingtin, including its role in neuronal migration, synaptogenesis, suppression of apoptosis, mitotic spindle orientation, and transcriptional regulation. We also discuss how mutant HTT may act through both loss- and gain-of-function mechanisms during early brain development. Comparative evolutionary analysis suggests that HTT is highly conserved and that the emergence of the N-terminal polyglutamine tract may have conferred developmental advantages in organisms with more complex nervous systems. Interestingly, studies in pre-symptomatic human carriers and mouse models have identified potential early-life cognitive benefits associated with moderate CAG expansion, raising the possibility of antagonistic pleiotropy. Understanding huntingtin's dual function in neurodevelopment and degeneration is essential in gaining insights into the earliest stages of HD pathogenesis, long before clinical onset.

Recent findings suggest that neurodevelopment plays a critical role in Huntington's Disease (HD) pathogenesis. This review integrates data from human studies of children and young adults at risk for HD (the Kids-HD study) with the theory of antagonistic pleiotropy (AP), which posits that genes promoting early-life advantages may confer late-life risks. Longitudinal imaging of gene-expanded (GE) children and adolescents shows that mHTT is associated with larger cortical volumes, enhanced surface morphology, and superior cognitive performance-decades before clinical onset. However, this early benefit is paired with accelerated striatal decline, suggesting that mHTT drives an early "ability" that transitions into a "liability." Vertex-wise analyses reveal cortical enlargement in regions with dense glutamatergic projections to the striatum, implicating excitotoxicity as a mechanism linking development to degeneration. This pleiotropic pattern parallels evolutionary models, where genes like HTT may have an evolutionary trade-off where genes supporting growth and reproduction are favored over those that serve long-term somatic maintenance, leaving cells with diminished repair capacity and resulting in an accelerated aging process. Altogether, these findings support a novel framework in which mHTT accelerates both brain maturation and neurodegeneration, offering new insights into HD biology and therapeutic targets.

IntroductionHuntington's Disease (HD) is a rare neurodegenerative disease that profoundly affects both individuals diagnosed with the condition and their caregivers. This review aims to examine the burden experienced by informal caregivers of patients with HD and identify relevant factors that exacerbate or mitigate this burden.MethodsThe PRISMA guidelines were followed, and an extensive search of electronic databases (PubMed, Science Direct, Taylor & Francis) was undertaken to identify original research articles published in English between January 2005 and April 2025. Two reviewers independently screened the studies. The quality of the studies was evaluated using the Critical Appraisal Program (CASP). Data were extracted, and a narrative synthesis was conducted to integrate and summarize the results.ResultsTwelve studies were included in the review involving 569 caregivers of patients with HD. Studies were conducted in Europe, the United States, Canada, and Australia, with one taking place in South Korea. Patient demographics, caregiver characteristics, disease-related factors, disrupted family dynamics, caregivers' compromised mental health, and availability to access networks are related to caregiver burden. Neuropsychiatric symptoms and the hereditary nature of the disease have been identified as important correlates of caregiver strain.ConclusionCaring for individuals with HD involves a distinct and multifaceted burden shaped by both the nature of the illness and inadequate external support. Addressing this requires future research to develop tailored interventions and tools that reflect the unique needs of HD caregivers across varying stages and cultural contexts.

BackgroundHuman Huntington's disease (HD) is a genetic neurodegenerative disorder caused by the mutant HTT gene containing CAG repeat expansions, resulting in motor dysfunction and behavioral deficits. CAG repeats of 40-53 occur in adult HD and 60-120 repeats occur in early onset juvenile HD, differing from the normal range of 5-35 repeats.ObjectiveThe HTT gene is translated to the huntingtin (HTT) protein that interacts with proteins in the development of HD. There have been few studies of HTT protein interactors in human HD brain. Therefore, this study evaluated the hypothesis that dysregulation of HTT protein interactors occurs in human juvenile HD brains.MethodsThe strategy of this study was to analyze proteomic data of human juvenile HD brain putamen and cortex regions for dysregulation of HTT interacting proteins, using a database that we compiled of HTT interactors identified in HD model systems from yeast to HD mice.ResultsResults showed significant dysregulation of HTT protein interactors of mitochondria, signal transduction, RNA splicing, chromatin organization, translation, membrane trafficking, endocytosis, vesicle, protein modification, granule membrane, and macroautophagy pathways. The majority of downregulated and upregulated HTT interactors occurred in the putamen region compared to cortex. Dysregulation displayed downregulation of mitochondria and signal transduction interactors, combined with upregulation of RNA splicing, chromatin organization, and translational interactors. Network analysis revealed interactions among clusters of HTT interactors.ConclusionsThese findings demonstrate prevalent dysregulation of HTT protein interactors in human juvenile HD brain, especially in the putamen region that controls movement deficits in HD.