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1.
Adv Exp Med Biol ; 1236: 225-244, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32304075

RESUMO

Genetic model systems allow researchers to probe and decipher aspects of human disease, and animal models of disease are frequently specifically engineered and have been identified serendipitously as well. Animal models are useful for probing the etiology and pathophysiology of disease and are critical for effective discovery and development of novel therapeutics for rare diseases. Here we review the impact of animal model organism research in three examples of congenital metabolic disorders to highlight distinct advantages of model system research. First, we discuss phenylketonuria research where a wide variety of research fields and models came together to make impressive progress and where a nearly ideal mouse model has been central to therapeutic advancements. Second, we review advancements in Lesch-Nyhan syndrome research to illustrate the role of models that do not perfectly recapitulate human disease as well as the need for multiple models of the same disease to fully investigate human disease aspects. Finally, we highlight research on the GM2 gangliosidoses Tay-Sachs and Sandhoff disease to illustrate the important role of both engineered traditional laboratory animal models and serendipitously identified atypical models in congenital metabolic disorder research. We close with perspectives for the future for animal model research in congenital metabolic disorders.


Assuntos
Modelos Animais de Doenças , Erros Inatos do Metabolismo , Animais , Gangliosidoses GM2 , Humanos , Doenças Raras/congênito , Doença de Sandhoff , Doença de Tay-Sachs
2.
Ann Neurol ; 87(4): 609-617, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31995250

RESUMO

OBJECTIVE: GM2 gangliosidoses are lysosomal diseases due to biallelic mutations in the HEXA (Tay-Sachs disease [TS]) or HEXB (Sandhoff disease [SD]) genes, with subsequent low hexosaminidase(s) activity. Most patients have childhood onset, but some experience the first symptoms during adolescence/adulthood. This study aims to clarify the natural history of adult patients with GM2 gangliosidosis. METHODS: We retrospectively described 12 patients from a French cohort and 45 patients from the literature. RESULTS: We observed 4 typical presentations: (1) lower motoneuron disorder responsible for proximal lower limb weakness that subsequently expanded to the upper limbs, (2) cerebellar ataxia, (3) psychosis and/or severe mood disorder (only in the TS patients), and (4) a complex phenotype mixing the above 3 manifestations. The psoas was the first and most affected muscle in the lower limbs, whereas the triceps and interosseous were predominantly involved in the upper limbs. A longitudinal study of compound motor action potentials showed a progressive decrease in all nerves, with different kinetics. Sensory potentials were sometimes abnormally low, mainly in the SD patients. The main brain magnetic resonance imaging feature was cerebellar atrophy, even in patients without cerebellar symptoms. The prognosis was mainly related to gait disorder, as we showed that beyond 20 years of disease evolution, half of the patients were wheelchair users. INTERPRETATION: Improved knowledge of GM2 gangliosidosis in adults will help clinicians achieve correct diagnoses and better inform patients on the evolution and prognosis. It may also contribute to defining proper outcome measures when testing emerging therapies. ANN NEUROL 2020;87:609-617.


Assuntos
Doença de Sandhoff/fisiopatologia , Doença de Tay-Sachs/fisiopatologia , Potenciais de Ação , Adolescente , Adulto , Idade de Início , Idoso , Atrofia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Criança , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Estudos de Coortes , Transtornos de Deglutição/fisiopatologia , Progressão da Doença , Disartria/fisiopatologia , Distonia/fisiopatologia , Eletrodiagnóstico , Eletromiografia , Feminino , Marcha Atáxica/fisiopatologia , Gangliosidoses GM2/diagnóstico por imagem , Gangliosidoses GM2/fisiopatologia , Gangliosidoses GM2/psicologia , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença dos Neurônios Motores/fisiopatologia , Espasticidade Muscular/fisiopatologia , Debilidade Muscular/fisiopatologia , Condução Nervosa , Doença de Sandhoff/diagnóstico por imagem , Doença de Sandhoff/psicologia , Doença de Tay-Sachs/diagnóstico por imagem , Doença de Tay-Sachs/psicologia , Adulto Jovem
3.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(9): 930-934, 2019 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-31515793

RESUMO

OBJECTIVE: To detect potential mutations of HEXB gene in an infant with Sandhoff disease (SD). METHODS: Genomic DNA was extracted from peripheral blood sample of the infant. All coding exons (exons 1 to 14) and splicing sites of the HEXB gene were subjected to PCR amplification and direct sequencing.PubMed Protein BLAST system was employed to analyze cross-species conservation of the mutant amino acid. PubMed BLAST CD-search was performed to identify functional domains destroyed by thecandidate mutations. Impact of the mutations was analyzed with software including PolyPhen-2, Mutation Taster and SIFT. Whole-exome sequencing was carried out to identify additional mutations. RESULTS: The infant was found to carry compound heterozygous mutations c.1652G>A(p.Cys551Tyr) and c.1389C>G (p.Tyr463*) of the HEXB gene. The c.1389C>G (p.Tyr463*) mutation may lead to destruction of two functional domains in ß subunit of the Hex protein. The c.1652G>A(p.Cys551Tyr) mutation, unreported previously,was predicted to be probably damaging by Bioinformatic analysis. CONCLUSION: Compound heterozygous mutations c.1652G>A(p.Cys551Tyr) and c.1389C>G (p.Tyr463*) in the HEXB gene probably underlie the disease in this patient.


Assuntos
Doença de Sandhoff/genética , Cadeia beta da beta-Hexosaminidase/genética , Análise Mutacional de DNA , Éxons , Heterozigoto , Humanos , Lactente , Mutação , Reação em Cadeia da Polimerase
4.
Metab Brain Dis ; 34(2): 495-503, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30712135

RESUMO

Gangliosidoses (GM1 and GM2 gangliosidosis) are rare, autosomal recessive progressive neurodegenerative lysosomal storage disorders caused by defects in the degradation of glycosphingolipids. We aimed to investigate clinical, biochemical and molecular genetic spectrum of Turkish patients with infantile gangliosidoses and examined the potential role of serum aspartate transaminase levels as a biomarker. We confirmed the diagnosis of GM1 and GM2 gangliosidosis based on clinical findings with specific enzyme and/or molecular analyses. We retrospectively reviewed serum aspartate transaminase levels of patients with other biochemical parameters. Serum aspartate transaminase level was elevated in all GM1 and GM2 gangliosidosis patients in whom the test was performed, along with normal alanine transaminase. Aspartate transaminase can be a biochemical diagnostic clue for infantile gangliosidoses. It might be a simple but important biomarker for diagnosis, follow up, prognosis and monitoring of the response for the future therapies in these patients.


Assuntos
Aspartato Aminotransferases/metabolismo , Biomarcadores/análise , Gangliosidoses/tratamento farmacológico , Doença de Sandhoff/tratamento farmacológico , Aspartato Aminotransferases/efeitos dos fármacos , Feminino , Gangliosidoses GM2/tratamento farmacológico , Gangliosidose GM1/tratamento farmacológico , Humanos , Masculino , Estudos Retrospectivos
5.
Mov Disord ; 34(5): 614-624, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30726573

RESUMO

Lysosomal storage disorders comprise a clinically heterogeneous group of autosomal-recessive or X-linked genetic syndromes caused by disruption of lysosomal biogenesis or function resulting in accumulation of nondegraded substrates. Although lysosomal storage disorders are diagnosed predominantly in children, many show variable expressivity with clinical presentations possible later in life. Given the important role of lysosomes in neuronal homeostasis, neurological manifestations, including movement disorders, can accompany many lysosomal storage disorders. Over the last decade, evidence from genetics, clinical epidemiology, cell biology, and biochemistry have converged to implicate links between lysosomal storage disorders and adult-onset movement disorders. The strongest evidence comes from mutations in Glucocerebrosidase, which cause Gaucher's disease and are among the most common and potent risk factors for PD. However, recently, many additional lysosomal storage disorder genes have been similarly implicated, including SMPD1, ATP13A2, GALC, and others. Examination of these links can offer insight into pathogenesis of PD and guide development of new therapeutic strategies. We systematically review the emerging genetic links between lysosomal storage disorders and PD. © 2019 International Parkinson and Movement Disorder Society.


Assuntos
Doenças por Armazenamento dos Lisossomos/genética , Transtornos Parkinsonianos/genética , Adulto , Criança , Galactosilceramidase/genética , Doença de Gaucher/genética , Glucosilceramidase/genética , Humanos , Leucodistrofia de Células Globoides/genética , Mucopolissacaridose III/genética , Mutação , Lipofuscinoses Ceroides Neuronais/genética , Doenças de Niemann-Pick/genética , Doença de Parkinson/genética , Fenótipo , ATPases Translocadoras de Prótons/genética , Doença de Sandhoff/genética , Esfingomielina Fosfodiesterase/genética
6.
Mol Genet Metab ; 126(2): 151-156, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30236619

RESUMO

Sandhoff disease (SD) results from mutations in the HEXB gene, subsequent deficiency of N-acetyl-ß-hexosaminidase (Hex) and accumulation of GM2 gangliosides. SD leads to progressive neurodegeneration and early death. However, there is a lack of established SD biomarkers, while the pathogenesis etiology remains to be elucidated. To identify potential biomarkers and unveil the pathogenic mechanisms, metabolomics analysis with reverse phase liquid chromatography (RPLC) was conducted. A total of 177, 112 and 119 metabolites were found to be significantly dysregulated in mouse liver, mouse brain and human hippocampus samples, respectively (p < .05, ID score > 0.5). Principal component analysis (PCA) analysis of the metabolites showed clear separation of metabolomics profiles between normal and diseased individuals. Among these metabolites, dipeptides, amino acids and derivatives were elevated, indicating a robust protein catabolism. Through pathway enrichment analysis, we also found alterations in metabolites associated with neurotransmission, lipid metabolism, oxidative stress and inflammation. In addition, N-acetylgalactosamine 4-sulphate, key component of glycosaminoglycans (GAG) was significantly elevated, which was also confirmed by biochemical assays. Collectively, these results indicated major shifts of energy utilization and profound metabolic impairments, contributing to the pathogenesis mechanisms of SD. Global metabolomics profiling may provide an innovative tool for better understanding the disease mechanisms, and identifying potential diagnostic biomarkers for SD.


Assuntos
Metaboloma , Doença de Sandhoff/metabolismo , Doença de Sandhoff/patologia , Animais , Biomarcadores/análise , Cromatografia Líquida , Modelos Animais de Doenças , Hipocampo/metabolismo , Humanos , Inflamação , Metabolismo dos Lipídeos , Masculino , Camundongos , Estresse Oxidativo , Transmissão Sináptica
7.
Orphanet J Rare Dis ; 13(1): 130, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-30075786

RESUMO

BACKGROUND: Infantile Sandhoff disease (ISD) is a GM2 gangliosidosis that is classified as a lysosomal storage disorder. The most common symptoms of affected individuals at presentation are neurologic involvement. Here we report clinical course and demographic features in a case series of infantile Sandhoff disease. Enzymatically and some genetically proven cases of ISD were extracted from the Iranian Neurometabolic Registry (INMR) in Children's Medical Center, Iran, Tehran from December 2010 to December 2016. RESULT: Twenty five cases of infantile SD (13 female, 12 male) were included in this study. The age range of patients was 9-24 months with a mean of 15.8 months. The consanguinity rate of parents affected families was about 80%. The mean age of patients at disease onset was 6.4 months and the mean age at diagnosis was 14 months. Patients were diagnosed with a mean delay of 7.8 months. Eleven of patients died due to aspiration pneumonia and intractable seizure. The most common features at presentation (92%) were developmental delay or regression in speech and cognitive domains. Cherry red spots were detected in 17 patients (68%). Organomegaly was detected only in two patients. Enzyme studies showed marked reductions of both Hexosaminidase A and B in all patients. HEXB gene mutation studies performed in eight patients identified 6 different mutations, which five of them were novel. CONCLUSION: Infantile SD should be considered for each child presented with neurologic symptoms such as developmental delay and regression and cherry red spots in ophthalmic examination. Organomegaly is not a frequent clinical finding in infantile SD. Additionally; there are a genetic heterogenisity among Iranian patients.


Assuntos
Mutação/genética , Doença de Sandhoff/genética , Doença de Sandhoff/patologia , Pré-Escolar , Feminino , Hexosaminidase A/genética , Humanos , Lactente , Irã (Geográfico) , Masculino , Cadeia beta da beta-Hexosaminidase/genética
9.
Neurobiol Dis ; 118: 142-154, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30026035

RESUMO

Astrocyte-microglia communication influences the onset and progression of central nervous system (CNS) disorders. In this study, we determined how chronic inflammation by activated astrocytes affected and regulated CNS functions in Sandhoff disease (SD), a CNS lysosomal storage disorder. SD triggers intense CNS inflammation such as microglial activation and astrogliosis. It is caused by mutation of the HEXB gene, which reduces ß-hexosaminidase (Hex) enzymatic activity in lysosomes, leading to accumulation of the substrate GM2 ganglioside in neuronal cells. Hexb-/- mice display a phenotype similar to human patients that suffer from chronic inflammation characterized by activation of astrocytes and microglia. In Hexb-/- mice, tremors and loss of muscle coordination begins at ~12 weeks. Interestingly, we found that reactive astrocytes expressed adenosine A2A receptor in the cerebral cortices of Hexb-/- mice at the later inflammatory phase. In cultured astrocytes, expression of A2A receptor could be induced by astrocyte defined medium, and then the activation of the A2A receptor induced ccl2 expression. In Hexb-/- mice, inhibition of the A2A receptor antagonized by istradefylline decreased the number of activated microglial cells and inflammatory cytokines/chemokines at 13 weeks. Thus, the astrocytic A2A receptor is an important sensor that regulates microglial activation in the late phase of inflammation.


Assuntos
Antagonistas do Receptor A2 de Adenosina/farmacologia , Astrócitos/metabolismo , Modelos Animais de Doenças , Microglia/metabolismo , Receptor A2A de Adenosina/metabolismo , Doença de Sandhoff/metabolismo , Antagonistas do Receptor A2 de Adenosina/uso terapêutico , Animais , Astrócitos/efeitos dos fármacos , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/efeitos dos fármacos , Purinas/farmacologia , Purinas/uso terapêutico , Doença de Sandhoff/tratamento farmacológico , Doença de Sandhoff/genética
10.
J Zoo Wildl Med ; 49(2): 335-344, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29900785

RESUMO

This study reports the occurrence of the lysosomal storage disease GM2 gangliosidosis (Sandhoff disease) in two 11-mo-old captive-bred, male and female mongoose siblings ( Mungos mungo). The clinical signs and the pathological findings reported here were similar to those reported in other mammalian species. Light microscopy revealed an accumulation of stored material in neurons and macrophages accompanied by a significant neuronal degeneration (swelling of neuronal soma, loss of Nissl substance, and neuronal loss) and gliosis. Electron microscopy of brain tissue identified the stored material as membrane-bound multilamellar bodies. An almost complete lack of total hexosaminidase activity in serum suggested a defect in the HEXB gene (Sandhoff disease in humans). High-performance thin-layer chromatography and mass spectrometry confirmed the accumulation of GM2 ganglioside in brain and kidney tissue, and the lectin staining pattern of the brain tissue further corroborated the diagnosis of a Sandhoff-type lysosomal storage disease.


Assuntos
Herpestidae , Doença de Sandhoff/veterinária , Animais , Animais de Zoológico , Feminino , Masculino , Doença de Sandhoff/diagnóstico , Doença de Sandhoff/patologia , Doença de Sandhoff/fisiopatologia
11.
Neuroreport ; 29(11): 962-967, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29847465

RESUMO

Sandhoff disease (SD) is a genetic disorder caused by a mutation of the ß-subunit gene ß-hexosaminidase B (HexB) in humans, which results in the massive accumulation of the ganglioside GM2 and related glycosphingolipids in the nervous system. SD causes progressive neurodegeneration and changes in white matter in human infants. An animal model of SD has been established, Hexb-deficient (Hexb) mice, which shows abnormalities resembling the severe phenotype found in human infants. Previously, we reported that the activation state of microglia caused astrogliosis in the early stage of Hexb mouse development. To study how the symptoms of SD develop, we explored the difference in gene expression between 4-week-old Hexb and Hexb mouse cerebral cortices by microarray analysis. The data indicated not only the upregulation of immune system-related genes but also the downregulation of myelin-related genes in the 4-week-old Hexb mouse cerebral cortices. To test the correlation between inflammation and dysmyelination, we generated double-knockout mice of Hexb and the Fc receptor γ gene (Fcrγ), which is a regulator of autoimmune responses. Dysmyelination recovered in these double-knockout mice. The number of oligodendrocyte progenitors, which expressed platelet-derived growth factor receptor-α, did not change in the 2-week-old mouse brain. These results indicate that microglial activation plays an important role in the myelination process, without influencing the number of oligodendrocyte progenitors, in the development of Hexb mice.


Assuntos
Gliose/metabolismo , Hexosaminidase B/farmacologia , Microglia/efeitos dos fármacos , Bainha de Mielina/metabolismo , Doença de Sandhoff/metabolismo , Animais , Modelos Animais de Doenças , Hexosaminidase B/metabolismo , Camundongos Knockout , Microglia/metabolismo , Regulação para Cima
12.
Curr Gene Ther ; 18(2): 68-89, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29618308

RESUMO

Tay-Sachs disease, caused by impaired ß-N-acetylhexosaminidase activity, was the first GM2 gangliosidosis to be studied and one of the most severe and earliest lysosomal diseases to be described. The condition, associated with the pathological build-up of GM2 ganglioside, has acquired almost iconic status and serves as a paradigm in the study of lysosomal storage diseases. Inherited as a classical autosomal recessive disorder, this global disease of the nervous system induces developmental arrest with regression of attained milestones; neurodegeneration progresses rapidly to cause premature death in young children. There is no effective treatment beyond palliative care, and while the genetic basis of GM2 gangliosidosis is well established, the molecular and cellular events, from diseasecausing mutations and glycosphingolipid storage to disease manifestations, remain to be fully delineated. Several therapeutic approaches have been attempted in patients, including enzymatic augmentation, bone marrow transplantation, enzyme enhancement, and substrate reduction therapy. Hitherto, none of these stratagems has materially altered the course of the disease. Authentic animal models of GM2 gangliodidosis have facilitated in-depth evaluation of innovative applications such as gene transfer, which in contrast to other interventions, shows great promise. This review outlines current knowledge pertaining the pathobiology as well as potential innovative treatments for the GM2 gangliosidoses.


Assuntos
Transplante de Medula Óssea , Terapia de Reposição de Enzimas , Terapia Genética , Doença de Sandhoff/genética , Doença de Sandhoff/terapia , Doença de Tay-Sachs/genética , Doença de Tay-Sachs/terapia , Animais , Modelos Animais de Doenças , Glicoesfingolipídeos/metabolismo , Humanos , Lactente , Lisossomos/enzimologia , Lisossomos/genética , Lisossomos/patologia , Camundongos , Mutação , Doenças Raras , Doença de Sandhoff/enzimologia , Doença de Sandhoff/patologia , Doença de Tay-Sachs/enzimologia , Doença de Tay-Sachs/patologia , beta-N-Acetil-Hexosaminidases/genética
13.
J Vet Intern Med ; 32(2): 797-804, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29478290

RESUMO

A 13-month-old female Toy Poodle was presented for progressive ataxia and intention tremors of head movement. The diagnosis of Sandhoff's disease (GM2 gangliosidosis) was confirmed by deficient ß-N-acetylhexosaminidase A and B activity in circulating leukocytes and identification of the homozygous mutation (HEXB: c.283delG). White matter in the cerebrum and cerebellum was hyperintense on T2-weighted and fluid-attenuated inversion recovery magnetic resonance images. Over the next 2 years, the white matter lesions expanded, and bilateral lesions appeared in the cerebellum and thalamus, associated with clinical deterioration. Magnetic resonance spectroscopy showed progressive decrease in brain N-acetylaspartate, and glycine-myo-inositol and lactate-alanine were increased in the terminal clinical stage. The concentrations of myelin basic protein and neuron specific enolase in cerebrospinal fluid were persistently increased. Imaging and spectroscopic appearance correlated with histopathological findings of severe myelin loss in cerebral and cerebellar white matter and destruction of the majority of cerebral and cerebellar neurons.


Assuntos
Doenças do Cão/líquido cefalorraquidiano , Doenças do Cão/diagnóstico por imagem , Doença de Sandhoff/veterinária , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Cães , Feminino , Seguimentos , Imagem por Ressonância Magnética/veterinária , Espectroscopia de Ressonância Magnética , Proteína Básica da Mielina/líquido cefalorraquidiano , Fosfopiruvato Hidratase/líquido cefalorraquidiano , Doença de Sandhoff/líquido cefalorraquidiano , Doença de Sandhoff/diagnóstico por imagem
14.
Hum Mol Genet ; 27(6): 954-968, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29325092

RESUMO

Sandhoff disease (SD) is a rare inherited disorder caused by a deficiency of ß-hexosaminidase activity which is fatal because no effective treatment is available. A mouse model of Hexb deficiency reproduces the key pathognomonic features of SD patients with severe ubiquitous lysosomal dysfunction, GM2 accumulation, neuroinflammation and neurodegeneration, culminating in death at 4 months. Here, we show that a single intravenous neonatal administration of a self-complementary adeno-associated virus 9 vector (scAAV9) expressing the Hexb cDNA in SD mice is safe and sufficient to prevent disease development. Importantly, we demonstrate for the first time that this treatment results in a normal lifespan (over 700 days) and normalizes motor function assessed by a battery of behavioral tests, with scAAV9-treated SD mice being indistinguishable from wild-type littermates. Biochemical analyses in multiple tissues showed a significant increase in hexosaminidase A activity, which reached 10-15% of normal levels. AAV9 treatment was sufficient to prevent GM2 and GA2 storage almost completely in the cerebrum (less so in the cerebellum), as well as thalamic reactive gliosis and thalamocortical neuron loss in treated Hexb-/- mice. In summary, this study demonstrated a widespread protective effect throughout the entire CNS after a single intravenous administration of the scAAV9-Hexb vector to neonatal SD mice.


Assuntos
Hexosaminidase B/farmacologia , Doença de Sandhoff/tratamento farmacológico , Doença de Sandhoff/patologia , Administração Intravenosa , Animais , Animais Recém-Nascidos , Encéfalo/metabolismo , Modelos Animais de Doenças , Feminino , Gangliosídeo G(M2)/metabolismo , Gangliosídeos/metabolismo , Hexosaminidase B/genética , Hexosaminidase B/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doença de Sandhoff/metabolismo
15.
J Lipid Res ; 59(3): 550-563, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29358305

RESUMO

Sandhoff disease, one of the GM2 gangliosidoses, is a lysosomal storage disorder characterized by the absence of ß-hexosaminidase A and B activity and the concomitant lysosomal accumulation of its substrate, GM2 ganglioside. It features catastrophic neurodegeneration and death in early childhood. How the lysosomal accumulation of ganglioside might affect the early development of the nervous system is not understood. Recently, cerebral organoids derived from induced pluripotent stem (iPS) cells have illuminated early developmental events altered by disease processes. To develop an early neurodevelopmental model of Sandhoff disease, we first generated iPS cells from the fibroblasts of an infantile Sandhoff disease patient, then corrected one of the mutant HEXB alleles in those iPS cells using CRISPR/Cas9 genome-editing technology, thereby creating isogenic controls. Next, we used the parental Sandhoff disease iPS cells and isogenic HEXB-corrected iPS cell clones to generate cerebral organoids that modeled the first trimester of neurodevelopment. The Sandhoff disease organoids, but not the HEXB-corrected organoids, accumulated GM2 ganglioside and exhibited increased size and cellular proliferation compared with the HEXB-corrected organoids. Whole-transcriptome analysis demonstrated that development was impaired in the Sandhoff disease organoids, suggesting that alterations in neuronal differentiation may occur during early development in the GM2 gangliosidoses.


Assuntos
Diferenciação Celular , Córtex Cerebral/patologia , Células-Tronco Pluripotentes Induzidas/patologia , Neurônios/patologia , Organoides/patologia , Doença de Sandhoff/patologia , Proliferação de Células , Células Cultivadas , Humanos , Lisossomos/metabolismo , beta-N-Acetil-Hexosaminidases/deficiência , beta-N-Acetil-Hexosaminidases/metabolismo
16.
J Vet Intern Med ; 32(1): 340-347, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29106755

RESUMO

BACKGROUND: GM2-gangliosidosis is a fatal neurodegenerative lysosomal storage disease (LSD) caused by deficiency of either ß-hexosaminidase A (Hex-A) and ß-hexosaminidase B (Hex-B) together, or the GM2 activator protein. Clinical signs can be variable and are not pathognomonic for the specific, causal deficiency. OBJECTIVES: To characterize the phenotype and genotype of GM2-gangliosidosis disease in an affected dog. ANIMALS: One affected Shiba Inu and a clinically healthy dog. METHODS: Clinical and neurologic evaluation, brain magnetic resonance imaging (MRI), assays of lysosomal enzyme activities, and sequencing of all coding regions of HEXA, HEXB, and GM2A genes. RESULTS: A 14-month-old, female Shiba Inu presented with clinical signs resembling GM2-gangliosidosis in humans and GM1-gangliosidosis in the Shiba Inu. Magnetic resonance imaging (MRI) of the dog's brain indicated neurodegenerative disease, and evaluation of cerebrospinal fluid (CSF) identified storage granules in leukocytes. Lysosomal enzyme assays of plasma and leukocytes showed deficiencies of Hex-A and Hex-B activities in both tissues. Genetic analysis identified a homozygous, 3-base pair deletion in the HEXB gene (c.618-620delCCT). CONCLUSIONS AND CLINICAL IMPORTANCE: Clinical, biochemical, and molecular features are characterized in a Shiba Inu with GM2-gangliosidosis. The deletion of 3 adjacent base pairs in HEXB predicts the loss of a leucine residue at amino acid position 207 (p.Leu207del) supporting the hypothesis that GM2-gangliosidosis seen in this dog is the Sandhoff type. Because GM1-gangliosidosis also exists in this breed with almost identical clinical signs, genetic testing for both GM1- and GM2-gangliosidosis should be considered to make a definitive diagnosis.


Assuntos
Doenças do Cão/genética , Gangliosidoses GM2/veterinária , Hexosaminidase B/genética , Doença de Sandhoff/veterinária , Animais , Encéfalo/diagnóstico por imagem , Doenças do Cão/diagnóstico por imagem , Doenças do Cão/patologia , Cães , Feminino , Gangliosidoses GM2/diagnóstico por imagem , Gangliosidoses GM2/genética , Imagem por Ressonância Magnética/veterinária , Doença de Sandhoff/diagnóstico por imagem , Doença de Sandhoff/genética , Análise de Sequência de Proteína , Deleção de Sequência
17.
Arch Argent Pediatr ; 115(5): e298-e301, 2017 Oct 01.
Artigo em Espanhol | MEDLINE | ID: mdl-28895707

RESUMO

Sandhoff disease is a neurodegenerative, lysosomal and autosomal recessive disease caused by mutations in the HEXB gene. Three forms are recognized: infantile, juvenile and adult. Previously, an endogamous population in Córdoba, Argentina, was identified with a high incidence of Sandhoff disease, all reported cases were of the infantile type. In this work, we describe a child with the juvenile form of Sandhoff disease, the first case reported in Argentina. The patient is a 7-year-old boy presenting with ataxia, speech disturbances and global developmental delay, symptoms starting at the age of 2 years. Diagnosis was based on the hexosaminidase deficiency. Sequencing of genomic DNA revealed compound heterozygosity for two HEXB gene mutations: c.796T>G (p.Y266D) and c.1615C>T (p.R539C), both already reported.


Assuntos
Doença de Sandhoff/diagnóstico , Argentina , Criança , Humanos , Masculino , Doença de Sandhoff/classificação
18.
PLoS One ; 12(6): e0178978, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28575132

RESUMO

In Sandhoff disease (SD), the activity of the lysosomal hydrolytic enzyme, ß-hexosaminidase (Hex), is lost due to a Hexb gene defect, which results in the abnormal accumulation of the substrate, GM2 ganglioside (GM2), in neuronal cells, causing neuronal loss, microglial activation, and astrogliosis. We established induced pluripotent stem cells from the cells of SD mice (SD-iPSCs). In the present study, we investigated the occurrence of abnormal differentiation and development of a neural lineage in the asymptomatic phase of SD in vitro using SD mouse fetus-derived neural stem cells (NSCs) and SD-iPSCs. It was assumed that the number of SD mouse fetal brain-derived NSCs was reduced and differentiation was promoted, resulting in the inhibition of differentiation into neurons and enhancement of differentiation into astrocytes. The number of SD-iPSC-derived NSCs was also reduced, suggesting that the differentiation of NSCs was promoted, resulting in the inhibition of differentiation into neurons and enhancement of that into astrocytes. This abnormal differentiation of SD-iPSCs toward a neural lineage was reduced by the glucosylceramide synthase inhibitor, miglustat. Furthermore, abnormal differentiation toward a neural lineage was reduced in SD-iPSCs with Hexb gene transfection. Therefore, differentiation ability along the time axis appears to be altered in SD mice in which the differentiation ability of NSCs is promoted and differentiation into neurons is completed earlier, while the timing of differentiation into astrocytes is accelerated. These results clarified that the abnormal differentiation of SD-iPSCs toward a neural lineage in vitro was shown to reflect the pathology of SD.


Assuntos
Astrócitos/patologia , Células-Tronco Pluripotentes Induzidas/patologia , Células-Tronco Neurais/patologia , Neurogênese , Neurônios/patologia , Doença de Sandhoff/patologia , Animais , Encéfalo/patologia , Contagem de Células , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL
20.
J Neuroimmunol ; 306: 55-67, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28385189

RESUMO

Sandhoff disease is an inherited lysosomal storage disease, resulting from the deficiency of lysosomal ß-hexosaminidase A and B enzyme activity. The Hexb-/- mouse model recapitulates human disease and leads to fatal neurodegeneration and neuroinflammation. IL-15 is important for the proliferation of NK, NK T, and CD8+ cytotoxic/memory T cells. In order to determine how changes to IL-15-dependent immune cell populations would alter the course of Sandhoff disease in mice, we generated a Hexb-/-Il-15-/- double knockout mouse and used motor behaviour tests, analyzed peripheral blood and brain leukocyte immunophenotypes, cytokine secretion, as well as examined markers of microgliosis, astrogliosis and apoptosis. Hexb-/-Il-15-/- mice had an accelerated neurodegenerative phenotype, and reached the humane endpoint at 118±3.5d, compared to Hexb-/- mice (127±2.2d). The performance of Hexb-/-Il-15-/- mice declined earlier than Hexb-/- mice on the rotarod and righting reflex motor behaviour tests. Hexb-/- mice had a significantly higher prevalence of pro-inflammatory monocytes in the blood relative to C57BL/6 mice, but this was unaltered by IL-15 deficiency. The prevalence of NK cells and CD8+ T cells in Il-15-/- and Hexb-/-Il-15-/- mice was decreased compared to wild type and Hexb-/- mice. While Hexb-/- mice displayed an increase in the prevalence of CD4+ and CD8+ T cells in brain leukocytes compared to C57BL/6 mice, there was a decrease in CD8+ T cells in Hexb-/-Il-15-/- compared to Hexb-/- mice. In addition, circulating IL-17 and IL-10 levels were significantly higher in Hexb-/-Il-15-/- mice, suggesting heightened inflammation compared to Hexb-/- mice. Interestingly, astrogliosis levels were significantly reduced in the cerebellum of Hexb-/-Il-15-/- mice compared to Hexb-/- mice while microgliosis was not affected in brains of Hexb-/-Il-15-/- mice. Our study demonstrated that IL-15 depletion dramatically reduced numbers of NK and CD8+ T cells as well as astrocytes but accelerated disease progression in Sandhoff mice. These results pointed to interactions between NK/CD8+ T cells and astrogliosis and potentially a protective role for NK/CD8+ T cells and/or astrocytes during disease progression. This observation supports the notion that expanding the IL-15-dependent NK and CD8+ T cells populations with IL-15 therapy may have therapeutic benefits for Sandhoff disease.


Assuntos
Linfócitos T CD8-Positivos/patologia , Doenças Cerebelares/etiologia , Gliose/terapia , Células Matadoras Naturais/patologia , Doença de Sandhoff/complicações , Doença de Sandhoff/mortalidade , Animais , Antígenos CD/metabolismo , Apoptose/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Doenças Cerebelares/genética , Doenças Cerebelares/patologia , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/genética , Proteína Glial Fibrilar Ácida/metabolismo , Hexosaminidase B/genética , Hexosaminidase B/metabolismo , Interleucina-15/genética , Interleucina-15/metabolismo , Células Matadoras Naturais/metabolismo , Locomoção/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transtornos dos Movimentos/etiologia , Transtornos dos Movimentos/genética , Doença de Sandhoff/genética
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