Huntington's disease (HD) is an inherited neurodegenerative disorder caused by the abnormal expansion of CAG trinucleotide repeats in the Huntingtin gene (HTT) located on chromosome 4. It is transmitted in an autosomal dominant manner and is characterized by motor dysfunction, cognitive decline, and emotional disturbances. To date, there are no curative treatments for HD have been developed; current therapeutic approaches focus on symptom relief and comprehensive care through coordinated pharmacological and nonpharmacological methods to manage the diverse phenotypes of the disease. International clinical guidelines for the treatment of HD are continually being revised in an effort to enhance care within a multidisciplinary framework. Additionally, innovative gene and cell therapy strategies are being actively researched and developed to address the complexities of the disorder and improve treatment outcomes. This review endeavours to elucidate the current and emerging gene and cell therapy strategies for HD, offering a detailed insight into the complexities of the disorder and looking forward to future treatment paradigms. Considering the complexity of the underlying mechanisms driving HD, a synergistic treatment strategy that integrates various factors-such as distinct cell types, epigenetic patterns, genetic components, and methods to improve the cerebral microenvironment-may significantly enhance therapeutic outcomes. In the future, we eagerly anticipate ongoing innovations in interdisciplinary research that will bring profound advancements and refinements in the treatment of HD.
Huntington Disease/pathology* ; Humans ; Genetic Therapy/methods* ; Animals ; Huntingtin Protein/genetics* ; Cell- and Tissue-Based Therapy/methods*

Quality control for genetic analysis has become more important with a drastic increase in testing volume and clinical demands. The molecular diagnostics division of the Korean Association of Quality Assurance for Clinical Laboratory conducted two trials in 2017 on the basis of molecular diagnostics surveys, involving 53 laboratories. The molecular diagnostics surveys included 37 tests: gene rearrangement tests for leukemia (BCR-ABL1, PML-RARA, AML1-ETO, and TEL-AML1), genetic tests for Janus kinase 2, FMS-like tyrosine kinase 3-internal tandem duplication, FMS-like tyrosine kinase 3-tyrosine kinase domain, nucleophosmin, cancer-associated genes (KRAS, EGFR, KIT, and BRAF), hereditary breast and ovarian cancer genes (BRCA1 and BRCA2), Li-Fraumeni syndrome (TP53), Wilson disease (ATP7B), achondroplasia (FGFR3), hearing loss and deafness (GJB2), Avellino (TGFBI), multiple endocrine neoplasia 2 (RET), Huntington disease, spinocerebellar ataxia, spinal and bulbar muscular atrophy, mitochondrial encephalopathy with lactic acidosis and stroke-like episodes, myoclonic epilepsy ragged red fibre, Leber hereditary optic neuropathy, Prader-raderd Angelman syndrome, Duchenne muscular dystrophy, spinal muscular atrophy, fragile X syndrome, apolipoprotein E genotyping, methylenetetrahydrofolate reductase genotyping, and ABO genotyping. Molecular genetic surveys revealed excellent results for most participants. The external quality assessment program for genetic analysis in 2017 proved useful for continuous education and the evaluation of quality improvement.
Achondroplasia ; Acidosis, Lactic ; Angelman Syndrome ; Apolipoproteins ; Brain Diseases ; Breast ; Deafness ; Education ; Epilepsies, Myoclonic ; Fragile X Syndrome ; Gene Rearrangement ; Hearing Loss ; Hepatolenticular Degeneration ; Huntington Disease ; Janus Kinase 2 ; Korea* ; Laboratory Proficiency Testing ; Leukemia ; Li-Fraumeni Syndrome ; Methylenetetrahydrofolate Reductase (NADPH2) ; Molecular Biology ; Multiple Endocrine Neoplasia ; Muscular Atrophy, Spinal ; Muscular Disorders, Atrophic ; Muscular Dystrophy, Duchenne ; Optic Atrophy, Hereditary, Leber ; Ovarian Neoplasms ; Pathology, Molecular* ; Phosphotransferases ; Quality Control ; Quality Improvement ; Spinocerebellar Ataxias ; Vascular Endothelial Growth Factor Receptor-1

Cholesterol is an essential component for neuronal physiology not only during development stage but also in the adult life. Cholesterol metabolism in brain is independent from that in peripheral tissues due to blood-brain barrier. The content of cholesterol in brain must be accurately maintained in order to keep brain function well. Defects in brain cholesterol metabolism has been shown to be implicated in neurodegenerative diseases, such as Alzheimer's disease (AD), Huntington's disease (HD), Parkinson's disease (PD), and some cognitive deficits typical of the old age. The brain contains large amount of cholesterol, but the cholesterol metabolism and its complex homeostasis regulation are currently poorly understood. This review will seek to integrate current knowledge about the brain cholesterol metabolism with molecular mechanisms.
ATP-Binding Cassette Transporters ; genetics ; metabolism ; Alzheimer Disease ; genetics ; metabolism ; pathology ; Blood-Brain Barrier ; Brain ; metabolism ; pathology ; Cholesterol ; metabolism ; Gene Expression Regulation ; Homeostasis ; Humans ; Huntington Disease ; genetics ; metabolism ; pathology ; Hydroxycholesterols ; metabolism ; Lipid Metabolism ; genetics ; Neurons ; metabolism ; pathology ; Parkinson Disease ; genetics ; metabolism ; pathology ; Receptors, Lipoprotein ; genetics ; metabolism

Induced pluripotent stem cells (iPSCs) generated from somatic cells of patients can provide immense opportunities to model human diseases, which may lead to develop novel therapeutics. Huntington's disease (HD) is a devastating neurodegenerative genetic disease, with no available therapeutic options at the moment. We recently reported the characteristics of a HD patient-derived iPSC carrying 72 CAG repeats (HD72-iPSC). In this study, we investigated the in vivo roles of HD72-iPSC in the YAC128 transgenic mice, a commonly used HD mouse model carrying 128 CAG repeats. To do this, we transplanted HD72-iPSC-derived neural precursors into the striatum of YAC128 mice bilaterally and observed a significant behavioral improvement in the grafted mice. Interestingly, the transplanted HD72-iPSC-derived neural precursors formed GABAeric neurons efficiently, but no EM48-positive protein aggregates were detected at 12 weeks after transplantation. Taken together, these results indicate no HD pathology was developed from the grafted cells, or no transmission of HD pathology from the host to the graft occurred at 12 weeks post-transplantation.
Animals ; GABAergic Neurons ; Humans ; Huntington Disease* ; Induced Pluripotent Stem Cells ; Mice ; Mice, Transgenic ; Neurons ; Pathology ; Pluripotent Stem Cells* ; Transplants

Hereditary spinocerebellar ataxia type 17 (SCA17) is an autosomal dominantly inherited progressive degenerative disease of the nervous system. Also known as Huntington's disease-like 4(HDL4), SCA17 mainly features ataxia, muscle dystonia and psychiatric symptoms. The gene predisposing to SCA17 has been mapped and cloned, which encodes a TATA-binding protein (TBP). A CAG repeat expansion in the coding region of TBP gene can cause polyglutamine chain extension in the protein. This paper reviews recent progress in the research on SCA17 in regard to its clinical, etiology, pathology and pathogenesis.
Animals ; Humans ; Huntington Disease ; genetics ; pathology ; Spinocerebellar Ataxias ; genetics ; pathology ; TATA-Box Binding Protein ; genetics ; Trinucleotide Repeat Expansion

Autophagy is a dynamic cellular pathway involved in the turnover of proteins, protein complexes, and organelles through lysosomal degradation. The integrity of postmitotic neurons is heavily dependent on high basal autophagy compared to non-neuronal cells as misfolded proteins and damaged organelles cannot be diluted through cell division. Moreover, neurons contain the specialized structures for intercellular communication, such as axons, dendrites and synapses, which require the reciprocal transport of proteins, organelles and autophagosomes over significant distances from the soma. Defects in autophagy affect the intercellular communication and subsequently, contributing to neurodegeneration. The presence of abnormal autophagic activity is frequently observed in selective neuronal populations afflicted in common neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease and amyotrophic lateral sclerosis. These observations have provoked controversy regarding whether the increase in autophagosomes observed in the degenerating neurons play a protective role or instead contribute to pathogenic neuronal cell death. It is still unknown what factors may determine whether active autophagy is beneficial or pathogenic during neurodegeneration. In this review, we consider both the normal and pathophysiological roles of neuronal autophagy and its potential therapeutic implications for common neurodegenerative diseases.
Alzheimer Disease/metabolism/pathology/physiopathology ; Animals ; Autophagy/*physiology ; Humans ; Huntington Disease/metabolism/pathology/physiopathology ; Models, Biological ; Neurodegenerative Diseases/metabolism/*pathology/physiopathology ; Neurons/*cytology ; Parkinson Disease/metabolism/pathology/physiopathology

Brain ; pathology ; Caudate Nucleus ; pathology ; Child, Preschool ; Humans ; Huntingtin Protein ; Huntington Disease ; diagnosis ; genetics ; pathology ; Magnetic Resonance Imaging ; Male ; Nerve Tissue Proteins ; genetics ; Pedigree ; Trinucleotide Repeats ; genetics