Child ; Humans ; Gaucher Disease/therapy*

Humans ; Gaucher Disease/pathology*

Child ; Consensus ; Gaucher Disease/therapy* ; Humans

Ceramide metabolism is known to be an essential etiology for various diseases, such as atopic dermatitis and Gaucher disease. Glucosylceramide synthase (GCS) is a key enzyme for the synthesis of glucosylceramide (GlcCer), which is a main ceramide metabolism pathway in mammalian cells. In this article, we developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to determine GCS activity using synthetic non-natural sphingolipid C8-ceramide as a substrate. The reaction products, C8-GlcCer for GCS, could be separated on a C18 column by reverse-phase high-performance liquid chromatography (HPLC). Quantification was conducted using the multiple reaction monitoring (MRM) mode to monitor the precursor-to-product ion transitions of m/z 588.6 → 264.4 for C8-GlcCer at positive ionization mode. The calibration curve was established over the range of 0.625–160 ng/mL, and the correlation coefficient was larger than 0.999. This method was successfully applied to detect GCS in the human hepatocellular carcinoma cell line (HepG2 cells) and mouse peripheral blood mononuclear cells. We also evaluated the inhibition degree of a known GCS inhibitor 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP) on GCS enzymatic activity and proved that this method could be successfully applied to GCS inhibitor screening of preventive and therapeutic drugs for ceramide metabolism diseases, such as atopic dermatitis and Gaucher disease.
Animals ; Calibration ; Carcinoma, Hepatocellular ; Cell Line ; Chromatography, Liquid ; Dermatitis, Atopic ; Gaucher Disease ; Humans ; Mass Screening ; Mass Spectrometry ; Metabolism ; Methods ; Mice

BACKGROUND AND OBJECTIVES: The antioxidant ebselen will be able to limit or prevent the ototoxicity arising from 2-hydroxypropyl-β-cyclodextrin (HPβCD). Niemann-Pick Type C (NPC) disease is a disorder of lysosomal storage manifested in sphingolipidosis. Recently, it was noted that experimental use of HPβCD could partially resolve the symptoms in both animals and human patients. Despite its desirable effect, HPβCD can induce hearing loss, which is the only major side effect noted to date. Understanding of the pathophysiology of hearing impairment after administration of HPβCD and further development of preventive methods are essential to reduce the ototoxic side effect. The mechanisms of HPβCD-induced ototoxicity remain unknown, but the resulting pathology bears some resemblance to other ototoxic agents, which involves oxidative stress pathways. To indirectly determine the involvement of oxidative stress in HPβCD-induced ototoxicity, we tested the efficacy of an antioxidant reagent, ebselen, on the extent of inner ear side effects caused by HPβCD. MATERIALS AND METHODS: Ebselen was applied prior to administration of HPβCD in mice. Auditory brainstem response thresholds and otopathology were assessed one week later. Bilateral effects of the drug treatments also were examined. RESULTS: HPβCD-alone resulted in bilateral, severe, and selective loss of outer hair cells from base to apex with an abrupt transition between lesions and intact areas. Ebselen co-treatment did not ameliorate HPβCD-induced hearing loss or alter the resulting histopathology. CONCLUSIONS: The results indirectly suggest that cochlear damage by HPβCD is unrelated to reactive oxygen species formation. However, further research into the mechanism(s) of HPβCD otopathology is necessary.
Animals ; Ear, Inner ; Evoked Potentials, Auditory, Brain Stem ; Hair Cells, Auditory, Outer ; Hearing Loss ; Hearing ; Humans ; Mice ; Oxidative Stress ; Pathology ; Reactive Oxygen Species ; Sphingolipidoses ; Tight Junctions

Gaucher Disease ; Humans

Gaucher disease is the most common of the lysosomal storage diseases caused by a defect in the lysosomal enzyme βglucocererbrosidase resulting in multi-organ involvement. The presence of cholelithiasis has been rarely observed among patients with non-neuronopathic type of Gaucher disease and the exact pathophysiology is still unknown. We report a Filipino child with chronic neuronopathic Gaucher Disease noted to have cholelithiasis on routine whole abdominal ultrasonography as part of the regular monitoring of the disease.
Gaucher Disease ; Cholelithiasis ; Gaucher Disease

No abstract available.
Adult ; Anticonvulsants/therapeutic use ; Bone Marrow/*pathology ; Epilepsies, Myoclonic/complications/*diagnosis/drug therapy ; Female ; Gaucher Disease/complications/*diagnosis/drug therapy ; Glucosylceramidase/genetics/therapeutic use ; Humans ; Phenotype ; Point Mutation ; Recurrence

Farber disease (FD) is a rare lysosomal storage disorder that shows autosomal recessive inheritance. We report the case of a 58-month-old girl with FD, who was misdiagnosed with epithelioid hemangioendothelioma. The patient had undergone five surgeries for sacrococcygeal masses and three surgeries for scalp masses owing to misdiagnosis. Here, we describe this rare case of FD.
Diagnostic Errors ; Farber Lipogranulomatosis* ; Female ; Hemangioendothelioma* ; Hemangioendothelioma, Epithelioid ; Humans ; Scalp ; Wills

BACKGROUNDGaucher's disease (GD) is an autosomal recessive disorder caused by a deficiency of acid β-glucosidase (glucocerebrosidase [GBA]) that results in the accumulation of glucocerebroside within macrophages. Many mutations have been reported to be associated with this disorder. This study aimed to discover more mutations and provide data for the genetic pattern of the gene, which will help the development of quick and accurate genetic diagnostic tools for this disease.

METHODSGenomic DNA was obtained from peripheral blood leukocytes of the patient and Sanger sequencing is used to sequence GBA gene. Sequence alignments of mammalian β-GBA (GCase) and three-dimensional protein structure prediction of the mutation were made. A construct of this mutant and its compound heterozygous counterpart were used to measure GCase in vitro.

RESULTSGCase is relatively conserved at p.T219A. This novel mutation differs from its wild-type in structure. Moreover, it also causes a reduction in GCase enzyme activity.

CONCLUSIONThis novel mutation (c.655A>G, p.T219A) is a pathogenic missense mutation, which contributes to GD.

Child, Preschool ; Gaucher Disease ; genetics ; Glucosylceramidase ; chemistry ; genetics ; Humans ; Male ; Models, Molecular ; Mutation, Missense ; Protein Structure, Tertiary ; Sequence Analysis, DNA