Doença de Tay-Sachs: relato de caso / Tay-Sachs disease: a case report

RESUMO A doença de Tay-Sachs é um distúrbio neurodegenerativo autossômico recessivo, o qual envolve o metabolismo dos lipídios, levando ao acúmulo de gangliosídeos nos tecidos, devido à deficiência da enzima hexosaminidase A. Esse depósito progressivo resulta em perda da função neurológica e, quando acomete as células ganglionares da mácula, causa o achado típico da doença, a "mácula em cereja". A patologia é diagnosticada por meio dos níveis de hexosaminidase A e hexosaminidase total no soro, além análise do DNA do gene HEXA. Este caso relata uma criança com doença de Tay-Sachs cujo diagnóstico foi suspeitado por conta dos achados oftalmológicos.

ABSTRACT Tay-Sachs Disease is an autosomal recessive neurodegenerative disorder, which involves the metabolism of lipids, leading to the accumulation of gangliosides in the tissues, due to the deficiency of the enzyme Hexosaminidase A. This progressive deposit results in loss of neurological function and, when it affects macula ganglion cells, it causes the typical disease finding, the "cherry red spot". The pathology is diagnosed through the levels of Hex A and total Hexosaminidase in the serum, in addition to the analysis of the DNA of the HEXA gene. This case reports a child with Tay-Sachs disease with a suspected diagnosis was through ophthalmologic findings.

In silico analysis of the effects of disease-associated mutations of b-hexosaminidase A in Tay–Sachs disease

Tay–Sachs disease (TSD), a deficiency of b-hexosaminidase A (Hex A), is a rare but debilitating hereditary metabolic disorder. Symptoms include extensive neurodegeneration and often result in death in infancy. We report an in silico study of 42 Hex A variants associated with the disease. Variants were separated into three groups according to the age of onset: infantile (n=28), juvenile (n=9) and adult (n=5). Protein stability, aggregation potential and the degree of conservation of residues were predicted using a range of in silico tools. We explored the relationship between these properties and the age of onset of TSD. There was no significant relationship between protein stability and disease severity or between protein aggregation and disease severity. Infantile TSD had a significantly higher mean conservation score than nondisease associated variants. This was not seen in either juvenile or adult TSD. This study has established that the degree of residue conservation may be predictive of infantile TSD. It is possible that these more highly conserved residues are involved in trafficking of the protein to the lysosome. In addition, we developed and validated software tools to automate the process of in silico analysis of proteins involved in inherited metabolic diseases. Further work is required to identify the function of well-conserved residues to establish an in silico predictive model of TSD severity

Tay-Sachs disease / Enfermedad de Tay-Sachs

Abstract Introduction: Lysosomal storage disease is caused by the deficiency of a single hydrolase (lysosomal enzymes). GM2 gangliosidoses are autosomal recessive disorders caused by deficiency of β-hexosaminidase and Tay-Sachs disease (TSD) is one of its three forms. Objective: To perform a review of the state of the art on TSD and describe its definition, epidemiology, etiology, physiopathology, clinical manifestations, as well as advances regarding its diagnosis and treatment. Materials and methods: A literature search was carried out in PubMed using the MeSH terms "Tay-Sachs Disease". Results: after the initial search was conducted, 1 233 results were retrieved, of which 53 articles were finally selected. TSD is caused by the deficiency of the lysosomal enzyme β-hexosaminidase A (HexA), and is characterized by neurodevelopmental regression, hypotonia, hyperacusis and cherry-red spots in the macula. Research on molecular pathogenesis and the development of possible treatments has been limited, consequently there is no treatment established to date. Conclusion: TSD is an autosomal recessive neurodegenerative disorder. Death usually occurs before the age of five. More research and studies on this type of gangliosidosis are needed in order to find an adequate treatment.

Resumen Introducción. La deficiencia de una sola hidrolasa (enzimas lisosomales) da como resultado una enfermedad de almacenamiento lisosomal. Las gangliosidosis GM2 son trastornos autosómicos recesivos causados por la deficiencia de β-hexosaminidasa. La enfermedad de Tay-Sachs (TSD, por sus siglas en inglés) es una de las tres presentaciones de este tipo de gangliosidosis. Objetivo. Realizar una revisión del estado del arte de la TSD describiendo su definición, epidemiología, etiología, fisiopatología, manifestaciones clínicas y actualidades en su diagnóstico y tratamiento. Materiales y métodos. Se realizó una búsqueda bibliográfica en PubMed utilizando como único término MeSH "Tay-Sachs Disease". Resultados. Se encontraron 1 233 publicaciones y se seleccionaron 53 artículos. La TSD es originada por la deficiencia de la enzima lisosomal β-hexosaminidasa A (HexA) y se caracteriza por regresión del neurodesarrollo, hipotonía, hiperacusia y manchas maculares rojo cereza. La investigación de la patogenia molecular y el desarrollo de posibles tratamientos han sido limitados y en la actualidad no se cuenta con uno plenamente establecido. Conclusiones. La TSD es un trastorno neurodegenerativo autosómico recesivo y por lo general la muerte se produce antes de los 5 años de edad. Son necesarias más investigaciones y estudios sobre este tipo de gangliosidosis con el fin de encontrar un tratamiento adecuado.

The Effects of Staphylococci on the Degranulation of Human Mast Cell-1

Atopic dermatitis (AD) is characterized by disturbances in epidermal barrier functions and the hyperactive immune response. Staphylococcus aureus (S. aureus) can be cultured from 90% of AD skin lesions and can exacerbate or contribute to the persistent skin inflammation in AD by secreting toxins with superantigenic properties. Superantigens can induce mast cell (MC) degranulation after penetrating the epidermal barrier. The role of MCs in AD is suggested by the increase in the MC number and MC activation. MCs are activated for degranulation and mediator release by allergens that cross-link IgE molecules or by microbial products. Therefore, MCs may be critically involved in the pathogenesis of AD. However, the understanding mechanisms of MC degranulation by S. aureus in relation to AD have still not been fully elucidated. In this study, we found that live S. aureus or methicillin-resistant S. aureus (MRSA) but not heat-killed bacteria induced MC degranulation. The heat-treatment partially inhibited MC degranulation by conditioned media (CM) of S. aureus or MRSA. The calcium chelator ethylene glycol tetraacetic acid (EGTA) did not block MC degranulation induced by live S. aureus or MRSA, but EGTA-treatment partially inhibited MC degranulation by CM from S. aureus or MRSA. These results suggest that live S. aureus and MRSA can degranulate MCs via direct interaction which may be important role in AD.

The Effects of Staphylococci on the Degranulation of Human Mast Cell-1

Atopic dermatitis (AD) is characterized by disturbances in epidermal barrier functions and the hyperactive immune response. Staphylococcus aureus (S. aureus) can be cultured from 90% of AD skin lesions and can exacerbate or contribute to the persistent skin inflammation in AD by secreting toxins with superantigenic properties. Superantigens can induce mast cell (MC) degranulation after penetrating the epidermal barrier. The role of MCs in AD is suggested by the increase in the MC number and MC activation. MCs are activated for degranulation and mediator release by allergens that cross-link IgE molecules or by microbial products. Therefore, MCs may be critically involved in the pathogenesis of AD. However, the understanding mechanisms of MC degranulation by S. aureus in relation to AD have still not been fully elucidated. In this study, we found that live S. aureus or methicillin-resistant S. aureus (MRSA) but not heat-killed bacteria induced MC degranulation. The heat-treatment partially inhibited MC degranulation by conditioned media (CM) of S. aureus or MRSA. The calcium chelator ethylene glycol tetraacetic acid (EGTA) did not block MC degranulation induced by live S. aureus or MRSA, but EGTA-treatment partially inhibited MC degranulation by CM from S. aureus or MRSA. These results suggest that live S. aureus and MRSA can degranulate MCs via direct interaction which may be important role in AD.

Effects of Total Saponins of Chaenomeles speciosa on Degranulation Ratio of RBL-2H3 Mast Cells / 医药导报

Objective To study the effects of total saponins of Chaenomeles speciosa on release of β-hexosaminidase from rat basophilic leukemia-2H3 ( RBL-2H3 ) mast cells. Methods After rat RBL-2H3 mast cells were prepared, total saponins of Chaenomeles speciosa and the RBL-2H3 mast cells were co-cultured.The toxic effects of total saponins of Chaenomeles speciosa on mast cells were detected by MTT method, β-hexosaminidase release rate was measured by fluorescence quantitative spectrophotometric method, and cell supernatants of tumor necrosis factor-α( TNF-α) release were detected by ELISA. Results After total saponins of Chaenomeles speciosa were co-cultured with RBL-2H3 mast cells with different antigen stimulation, β-hexosaminidase release rates and the levels of TNF-α of mast cells significantly decreased compared with the control group. Conclusion Total saponins of Chaenomeles speciosa inhibit the degranulation of RBL-2H3 mast cells in a dose dependent manner, which provids basis for studying mechanism of inhibiting allergic reactions.

Application of RBL-2H3 cells on allergenicity assessment of Qing kailing and Tanreqing Injections / 中草药

Objective: To explore the allergenicity of two kinds of Chinese materia medica (CMM) injections, Qingkailing (QKL) and Tanreqing (TRQ) Injections, with serum antibody sensitized RBL-2H3 cells. Methods: The antiserum was prepared by sc injection of allergen composed of ovalbumin (OVA), QKL, or TRQ combined with aluminum hydroxide adjuvant respectively in Wistar rats. The total IgE level in serum antibody was determined by radioimmunoassay. The RBL-2H3 cells were sensitized with serum antibodies, then stimulated by OVA, QKL, or TRQ after 48 h. The release rate of β-hexosaminidase in the supernatant was determined after the degranulation of sensitized RBL-2H3 cells. Passive cutaneous anaphylaxis (PCA) test was performed with rats, and the positive reaction rate with blue plaque in animal skin was observed. Results: Compared with the control group, the total IgE level in serum antibody was increased significantly in OVA, TRQ, and QKL groups (P < 0.05). The degranulation test revealed that the release rate of β-hexosaminidase was significantly increased in the supernatant when the cells were incubated with the antiserum and then stimulated with OVA, QKL, and TRQ. Compared with the control group, the largest relative times of release were 3.7, 1.53, and 1.98, respectively. The results of PCA test showed that the highest percentage rates of positive reaction of blue plaque were 100%, 100%, and 86% respectively. The results of RBL-2H3 cell test and PCA test have good consistency. Conclusion: The serum antibody sensitized RBL-2H3 cell model can be used for screening or assessing allergenicity of CMM injection.

Study of degranulation induced by the chemical composition of polysorbate 80 in a rat mast (RBL-2H3) cell line / 中国药学杂志

OBJECTIVE: To study directive effects of eight types of the chemical composition of polysorbate 80 on the degranulation in the RBL-2H3 rat mast cell line and to illuminate the material basis for its pseudoallergy. METHODS: RBL-2H3 cells were cultured and treated with varying dosage of eight types of the chemical composition of polysorbate 80. And then the amount of the released β-hexosaminidase was detected. MTT assay was used to determine the cytotoxicity of eight types of the chemical composition of polysorbate 80 which causing RBL-2H3 cells degranulation. RESULTS: PSM, PSD and PIM induced RBL-2H3 cells' degranulation in a concentration-dependent manner. Degranulation was not detected in cells treated with PS and PI. PSTri, PSTetra and PSD weakly induced the degranulation of RBL-2H3 cells in a concentration-dependent manner. PSM, PSD and PIM showed cytotoxicity with concentration-dependent manner, while PS and PI had no cytotoxicity. PSTri, PSTetra and PSD showed low toxicity cytotoxicity in a concentration-dependent manner. CONCLUSION: PIM is a major source of toxic substances polysorbate 80, the limit of which must be controlled.

"Influences of ""Antiphlogistic No.1"" on the degranultion of Activated RBL-2H3 cells" / 国际中医中药杂志

Objective To investigate the direct effect ofAntiphlogistic No.1 on the degranultion of RBL-2H3 mast cells stimulated by anti-DNP IgE and DNP-BSA complex.Methods The effect of Antiphlogistic No.1 on stabilization of RBL-2H3 cell membrane was assessed by degranultion inhibition rate.β-hexosaminidase and IL-4 released from RBL-2H3 cells were detected by PNAG colorimetric assay and ELISA.Results β-hexosaminidase and cytokine IL-4 production releases from RBL-2H3 cells was reduced after they had been treated with Antiphlogistic No.1.The inhibition rate of β-hexosaminidase release was 42.47％ at the concentration of 8 μg/ml (P＜0.01) and dose dependently increased to 52.40％,68.26％ and 72.15％ respectively when drug concentration up to 80 μg/ml,800 μg/ml,8000 μg/ml,while inhibition rate of IL-4 generation were 13.87％,23.27％,31.95％,39.99％ (P＜0.01).Antiphlogistic No.1 maximum inhibition rate of β-hexosaminidase release is 84.48％ of dexamethason maximum inhibition rate while Antiphlogistic No.l maximum inhibition rate of IL-4 is close to dexamethason maximum inhibition rate.Conclusion Antiphlogistic No.1 could stabilize the cellular membrane of RBL-2H3 and provide protection against Ⅰ type allergic response.

Intracellular Ca2+ Mobilization and Beta-hexosaminidase Release Are Not Influenced by 60 Hz-electromagnetic Fields (EMF) in RBL 2H3 Cells

The effects of extremely low frequency electromagnetic fields (EMF) on intracellular Ca2+ mobilization and cellular function in RBL 2H3 cells were investigated. Exposure to EMF (60 Hz, 0.1 or 1 mT) for 4 or 16 h did not produce any cytotoxic effects in RBL 2H3 cells. Melittin, ionomycin and thapsigargin each dose-dependently increased the intracellular Ca2+ concentration. The increase of intracellular Ca2+ induced by these three agents was not affected by exposure to EMF (60 Hz, 1 mT) for 4 or 16 h in RBL 2H3 cells. To investigate the effect of EMF on exocytosis, we measured beta-hexosaminidase release in RBL 2H3 cells. Basal release of beta-hexosaminidase was 12.3+/-2.3% in RBL 2H3 cells. Exposure to EMF (60 Hz, 0.1 or 1 mT) for 4 or 16 h did not affect the basal or 1 microM melittin-induced beta-hexosaminidase release in RBL 2H3 cells. This study suggests that exposure to EMF (60 Hz, 0.1 or 1 mT), which is the limit of occupational exposure, has no influence on intracellular Ca2+ mobilization and cellular function in RBL 2H3 cells.

Anti-Oxidative and Anti-Inflammatory Effect of Water Extract from Perillae semen in RBL-2H3 Cells

The present study was to investigate anti-oxidative and anti-inflammatory activity of Perillae semen in RBL-2H3 basophilic leukemia cells. Inhibitory effect of Perillae semen onto free radical generation was determined by measuring DPPH and hydroxyl radical scavenging activities in vitro. Anti-inflammatory actions of Perillae semen extracts (100, 250, 500 microgram/mL) were assessed by testing their effects on the degranulation of mast cells. For this, beta-hexosaminidase released from RBL-2H3 cells was used and proinflammatory cytokines were measured by an ELISA kit. Our results indicated that Perillae semen water extracts effectively inhibited free radical generation. At the concentration of 500 microgram/mL of water extract, the degranulation of RBL-2H3 cells were inhibited by 42.1%. The IgE-antigen complex increased the accumulation of IL-4 and TNF-alpha secretion in RBL-2H3 cells and treatments with 250 and 500 microgram/mL of Perillae semen extracts suppressed the IgE induced secretion of IL-4 and TNF-alpha protein by 20.5, 26.9% and 14.5, 16.5% respectively. We observed that Perillae semen water extract reduced beta-hexosaminidase, IL-4, and TNF-alpha secretion in RBL-2H3 cells. These results provide that Perillae semen may be beneficial in the treatment of allergic inflammatory disease.

An Anesthetic Experience in a Patient with Tay-Sachs Disease : A case report / 대한마취과학회지

Tay-Sachs Disease (TSD), the most common form of GM(2) gangliosidosis, is an autosomal recessive inborn lysosomal glycosphingolipid storage disease which is resulted from the mutations that affect the alpha-subunit locus on chromosome 15 and cause a severe deficiency of hexosaminidase A. It is characterized by normal motor development in the first few months of life, followed by progressive weakness and loss of motor skills beginning around 6 months of life. Neurodegeneration is relentless and manifested as relentless motor and mental deterioration, beginning with motor incoordination, mental obtundation leading to muscular flaccidity, blindness, and increasing dementia, with death occurring by the age of 4 or 5 years. We report a successful anesthetic management in a patient with Tay-Sachs Diseases for tracheostomy and feeding gastrostomy.

A Case Refort of Sandhoff Disease

Sandhoff disease is a rare autosomal recessive metabolic disease presenting bilateral optic atrophy and a cherry red spot in the macula. This case report presents the characteristics of a patient with Sandhoff disease as assessed by ophthalmic, neuroimaging, and laboratory procedures. Ophthalmologic examination revealed that the patient could not fixate her eyes on objects nor follow moving targets. A pale optic disc and a cherry red spot in the macula were seen in both eyes. Low signal intensity at the thalamus and high signal intensity at the cerebral white matter were noted in a T2-weighted brain MR image. A lysosomal enzyme assay using fibroblasts showed the marked reduction of both total beta-hexosaminidases, A and B. Based on the above clinical manifestations and laboratory findings, we diagnosed the patient as having Sandhoff disease.

GM2 Gangliosidosis II / 대한소아신경학회지

GM2 gangliosidosis II(Sandhoff disease) is a lysosomal storage disease due to deficiency of beta-hexosaminidase activity, transmitted by mode of autosomal recessive. Clinical features are so variable, ranging from infantile onset resulting death before 4 years, to subacute or chronic forms with more slowly progressive neurologic condition. We experienced a case of GM2 gangliosidosis II in a 14 months old male who had developmental deterioration and seizures, so we report and review the related literatures.