• Journal of mucopolysaccharidosis and rare diseases
• /
• 제4권1호
• /
• pp.26-36
• /
• 2018

Mucopolysaccharidosis IIIA is a heritable neurodegenerative disorder resulting from the dysfunction of the lysosomal hydrolase sulphamidase. This leads to the primary accumulation of the complex carbohydrate heparan sulphate in a wide range of tissues and CNS degeneration. Characterization of animal model is the beginning point of the therapeutic clinical trial. Mouse model has a limitation in that it is not a human and does not have all of the disease phenotypes. Therefore, delineate of the phenotypic characteristics of MPS IIIA mouse model prerequisite for the enzyme replace treatment for the diseases. We designed 6-month duration of phenotypic characterization of MPS IIIA mouse biochemically, behaviorally and histologically. We compared height and weight of MPS IIIA mouse with wild type from 4 weeks to 6 months in both male and female. At 6 months, we measured GAG storage in urine kidney, heart, liver, lung and spleen. The brain GAG storage is presented with Alcian blue staining, immunohistochemistry, and electron-microscopy. The neurologic phenotype is evaluated by brain MRI and behavioral study including open field test, fear conditioning, T-maze test and Y-maze test. Especially behavioral tests were done serially at 4month and 6month. This study will show the result of the MPS IIIA mouse model phenotypic characterization. The MPS IIIA mouse provides an excellent model for evaluating pathogenic mechanisms of disease and for testing treatment strategies, including enzyme or cell replacement and gene therapy.

• 대한세포병리학회지
• /
• 제7권1호
• /
• pp.79-83
• /
• 1996

Gaucher's disease is an autosomal recessive disorder resulting from mutation at the glucocerebrosidase locus on chromosome 1q21. As a result, glucocerebroside accumulates principally in the phagocytic cells known as Gaucher cells. In our case, a five-year old girl was admitted with seven days' history of fever and abdominal distension. At physical examination the patient had hepatosplenomegaly. Laboratory tests revealed a hemoglobin concentration of 2.8g/L: platelet counts of $23,000/{\mu}l$: normal range of white cell and differential counts, and negative Coombs' test. Liver enzymes were normal. For the evaluation of hepatosplenomegaly, fine needle aspiration was performed blindly against the palpable spleen. Wet-fixed hematoxylin and eosin-stained smears are made. The smears from the spleen showed predominantly macrophages with abundant cytoplasm and rather small, uniform, often eccentric nuclei with small nucleoli. The multinucleated cells were often found. The cytoplasm was pale, with more or less distinct fibrillarity. The cells had the characteristic appearance of Gaucher cells. Gaucher cells were also found in the tissue section from the liver, spleen and lymph node and the bone marrow aspirate. The diagnosis was later confirmed by determination of bela-glucosidase activity in peripheral blood leucocytes. Fine needle aspiration of the spleen is considered as a convenient procedure with a low complication rate for the diagnosis of lysosomal storage disease.

• Journal of Genetic Medicine
• /
• 제13권2호
• /
• pp.59-64
• /
• 2016

Gaucher disease type 1 (GD1) is an inherited lysosomal storage disorder caused by deficiency of acid ${\beta}$-glucosidase. The diminished enzyme activity leads to the accumulation of substrates and results in multi-systemic manifestations including hepatosplenomegaly, anemia, thrombocytopenia, and bone diseases. Enzyme replacement therapy (ERT) by infusion of recombinant protein has been the standard treatment for over 20 years. Despite the successful long-term treatment with ERT, several unmet needs remain in the treatment of GD1 such as severe pulmonary and skeletal manifestations. Substrate reduction therapy (SRT) reduces the accumulation of substrates by inhibiting their biosynthesis. Eliglustat, a new oral SRT, was approved in United States and Europe as a first-line therapy for treating adult patients with GD1 who have compatible CYP2D6 metabolism phenotypes. Although eliglustat is not yet available in Korea, introduction and summary of this new treatment modality are provided in this paper by review of literatures. Despite the fact that there are only limited studies to draw resolute conclusions, the current data demonstrated that eliglustat is not inferior to ERT in terms of its clinical efficacy. The approval of eligustat enables eligible adult GD1 patients to have the option of oral therapy although it still needs further studies on long-term outcomes. The individual patient should be assessed carefully for the choice of treatment modality when eliglustat becomes available in Korea. Furthermore, the clinical guidelines for Korean patients with GD1 regarding the use of eliglustat needs to be developed in near future.

• Journal of Genetic Medicine
• /
• 제20권1호
• /
• pp.6-14
• /
• 2023

Fabry disease (FD), a rare X-linked lysosomal storage disorder, is caused by mutations in the α-galactosidase A gene gene encoding α-galactosidase A (α-Gal A). The functional deficiency of α-Gal A results in progressive accumulation of neutral glycosphingolipids, causing multi-organ damages including cardiac, renal, cerebrovascular systems. The current treatment is comprised of enzyme replacement therapy (ERT), oral pharmacological chaperone therapy and adjunctive supportive therapy. ERT has been introduced 20 years ago, changing the outcome of FD patients with proven effectiveness. However, FD patients have many unmet needs. ERT needs a life-long intravenous therapy, inefficient bio-distribution, and generation of anti-drug antibodies. Migalastat, a pharmacological chaperone, augmenting α-Gal A enzyme activity only in patients with mutations amenable to the therapy, is now available for clinical practice. Furthermore, these therapies should be initiated before the organ damage becomes irreversible. Development of novel drugs aim at improving the clinical effectiveness and convenience of therapy. Clinical trial of next generation ERT is underway. Polyethylene glycolylated enzyme has a longer half-life and potentially reduced antigenicity, compared with standard preparations with longer dosing interval. Moss-derived enzyme has a higher affinity for mannose receptors, and seems to have more efficient access to podocytes of kidney which is relatively resistant to reach by conventional ERT. Substrate reduction therapy is currently under clinical trial. Gene therapy has now been started in several clinical trials using in vivo and ex vivo technologies. Early results are emerging. Other strategic approaches at preclinical research level are stem cell-based therapy with genome editing and systemic mRNA therapy.

• Journal of mucopolysaccharidosis and rare diseases
• /
• 제3권1호
• /
• pp.33-33
• /
• 2017

• 대한유전성대사질환학회지
• /
• 제13권1호
• /
• pp.37-42
• /
• 2013

Gaucher disease is a lysosomal storage disease caused by deficiency of glucocerebrosidase (GBA). This condition is characterized by accumulation of glucocerebrosidase in liver, spleen, lung, skeletal system, and central nervous system. Gaucher disease is the prototype of disease in which efficacy of enzyme replacement therapy has been established. However, because recombinant enzyme is not able to enter the central nervous system, its efficacy is limited to the non-neurological manifestations of Gaucher disease. Importantly, approximately a half of Korean patients with Gaucher disease suffer from neurological manifestations. In addition, Korean Gaucher disease patients exhibit distinct mutation spectrum from those in other populations. Common mutations in Korean patients with Gaucher disease are also associated with neurological phenotype. Therefore, therapeutic strategies tailored to Korean patients were necessary. Interestingly, a chemical chaperone, ambroxol, has been known to increase residual enzymatic activities of the select mutant GBAs encoded by mutations prevalent in Korean patients. One promising aspect of this drug is that it can cross blood-brain barrier, and enhance the enzyme activity in the brain. In vitro study suggested this chemical chaperone as one of new therapeutic agents in Gaucher disease, and a well-designed human trial is required to confirm its efficacy.

• 생명과학회지
• /
• 제20권8호
• /
• pp.1281-1286
• /
• 2010

고셔병은 세포내의 글루코세레브로시데이즈의 결핍으로 인하여 리소좀 내의 글루코세레브로사이드가 분해되지 못하고 축적되는 질환으로 알려져 있으며, 유형의 종류에 따라 신경퇴행성 질환으로 나타나는 것으로 보고되어 있으나 아직까지 정확한 기전이 밝혀져 있지 않다. 본 논문에서는 항산화 효과 및 신경보호 효과가 있는 것으로 알려진 레스베라트롤을 고셔병 환자의 fibroblast 세포에 투여하여 세포 생존율 변화 여부 및 세포주기 조절에 관하여 분자 생물학적 기전을 알아보고자 하였다. 고셔병 세포의 p21의 mRNA 발현 수준과 단백질 발현 양상을 확인한 결과 mRNA 상의 정량적 차이는 관찰되지 않았으나 단백질 발현수준은 레스베라트롤의 농도가 높아짐에 따라 증가 되는 것을 확인하였다. 또한 세포사멸의 표지 인자 단백질로 알려진 PARP의 변화양상을 확인한 결과 레스베라트롤의 농도가 높아짐에 따라 감소하는 것을 확인 할 수 있었다. 이를 통해 폴리페놀계 천연물인 레스베라트롤이 고셔병에서 세포 손상을 치유하며, 궁극적으로 세포사멸을 억제하는 효과를 가져올 것으로 생각할 수 있으며, 본 질환에서 병증을 완화 시킬 수 있을 것으로 사료된다.

• 대한유전성대사질환학회지
• /
• 제20권1호
• /
• pp.1-13
• /
• 2020

Gaucher disease (GD)는 glucocerebrosidase 유전자(GBA)의 돌연변이에 의하여 발병하는 전세계적으로 가장 유병율이 높은 리소좀 축적질환이다. GD는 신경학적인 증상의 유무에 따라 3가지 임상형으로 구분된다. 신경병증 GD인 2형과 3형의 경우는 대뇌에서 glucosylceramide (GlcCer)와 glucosylsphingosine (GlcSph)의 농도가 증가하면서 신경세포의 심각한 손실이 야기되는 특징을 보인다. 신경교종에서 유래한 H4 세포를 GD에서 증가하는 기질인 GluCer와 GlcSph를 첨가하여 배양하였을 때, 심각한 DNA손상과 더불어 세포의 사멸이 야기되는 것과 이러한 신경세포의 사멸은 GluCer 보다는 GlcSph을 처리하였을 때 더 현저하게 증가하는 것을 관찰하였다. H4 세포에 히스톤 탈아세틸화 효소(HDAC) 6의 저해제인 tubacin과 GlcSph을 함께 처리하였을 경우에는 DNA손상은 물론 GlcSph에 의하여 유도된 세포사멸과 관련된 단백질 인자들의 발현이 모두 감소되었다. 본 연구를 통해 GlcSph이 세포사멸을 통하여 신경병증 GD의 발병에 주요한 역할을 한다는 것을 알 수 있었고, HDAC6 저해제가 신경병증 GD 환자를 위한 치료제 후보물질로 제시될 수 있는 가능성을 확인하였다.

• Clinical and Experimental Pediatrics
• /
• 제55권3호
• /
• pp.88-92
• /
• 2012

Purpose: Mucopolysaccharidosis type II (MPS II or Hunter syndrome) is a rare lysosomal storage disorder caused by iduronate-2-sulfatase (IDS) deficiency. MPS II causes a wide phenotypic spectrum of symptoms ranging from mild to severe. IDS activity, which is measured in leukocyte pellets or fibroblasts, was reported to be related to clinical phenotype by Sukegawa-Hayasaka et al. Measurement of residual plasma IDS activity using a fluorometric assay is simpler than conventional measurements using skin fibroblasts or peripheral blood mononuclear cells. This is the first study to describe the relationship between plasma IDS activity and clinical phenotype of MPS II. Methods: We hypothesized that residual plasma IDS activity is related to clinical phenotype. We classified 43 Hunter syndrome patients as having attenuated or severe disease types based on clinical characteristics, especially intellectual and cognitive status. There were 27 patients with the severe type and 16 with the attenuated type. Plasma IDS activity was measured by a fluorometric enzyme assay using 4-methylumbelliferyl- ${\alpha}$-iduronate 2-sulphate. Results: Plasma IDS activity in patients with the severe type was significantly lower than that in patients with the attenuated type ($p$=0.006). The optimal cut-off value of plasma IDS activity for distinguishing the severe type from the attenuated type was 0.63 $nmol{\cdot}4hr^{-1}{\cdot}mL^{-1}$. This value had 88.2% sensitivity, 65.4% specificity, and an area under receiver-operator characteristics (ROC) curve of 0.768 (ROC curve analysis; $p$=0.003). Conclusion: These results show that the mild phenotype may be related to residual lysosomal enzyme activity.

• Journal of mucopolysaccharidosis and rare diseases
• /
• 제3권1호
• /
• pp.20-27
• /
• 2017

Purpose: Mucopolysaccharidosis IV (MPS IV) is a disease characterized by deficient activity of N-acetylgalactosamine-6-sulfatase (GALNS) causing excessive lysosomal storage of keratan sulfate (KS). The identification of the relevant disaccharide units of KS after keratanase II digestion followed by liquid chromatography/tandem mass spectrometry detection (LC-MS/MS) is validated and applicable for the preliminary diagnosis of MPS IV. Methods: A total of 67 urine samples were collected and analyzed from 11 MPS IV patients comprising 10 MPS IVA and one MPS IVB patients, and 56 normal controls. Urinary glycosaminoglycan was first precipitated by the Alcian blue method followed by a digestion of keratanase II. The protonated species of the digested disaccharide products were detected by using multiple reaction monitoring experiment. Results: One particular disaccharide of KS was selected. The transition mass-to-charge (m/z) of the parent ion and its daughter ion after collision was $462.0{\rightarrow}97.0$, whereas the chondrosine used as an internal standard in this assay was m/z $353.9{\rightarrow}73.0$. The results corresponded well with the two-dimensional electrophoresis method. The quantities of urinary KS were significantly raised in confirmed MPS IV patients when comparing with those of normal controls ($170.2{\pm}81.1$ vs. $4.06{\pm}1.92{\mu}g/mL$). Conclusion: The LC-MS/MS method for MPS IVA determination is specific, sensitive, validated, and applicable for urinary KS quantification. This method can be used not only as a first-line biochemistry examination of MPS IVA, but also as an outcome survey after enzyme replacement therapy.