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Hughes D.A.,Lysosomal Storage Disorders Unit | Ramaswami U.,Addenbrookes Hospital | Barba Romero M.-A.,Albacete University Hospital | Deegan P.,Addenbrookes Hospital
Molecular Genetics and Metabolism | Year: 2010

Anderson-Fabry Disease (AFD) is a life-threatening X-linked lysosomal storage disorder, caused by a deficiency of alpha galactosidase A. The disease affects males and females, and may present in childhood or adulthood. In the absence of a biomarker of disease burden or therapeutic response, scoring systems based on clinical manifestations, have been developed. Such global scores e.g. the Mainz Severity Score Index (MSSI) are confounded by the natural history of disease that deteriorates with age, making comparisons across age groups invalid.In this study the baseline MSSI, as adapted for data collected in the Fabry Outcome Survey (FOS) database (FOS-MSSI), was calculated for 655 females and 617 males with confirmed AFD. Using an ANCOVA model, equations for the predicted FOS-MSSI based on age were derived for males and females from data where patients from the UK or outside Europe were excluded. The initially excluded patients were used for validation.The predicted severity scores of UK and non-Europe-cohorts of adult and paediatric patients were found to follow the model produced for the European cohort thereby providing validation of the methodology. Deviation of the actual FOS-MSSI from the predicted was calculated and termed the age-adjusted score. Examples of the use of the age-adjusted score in individual patients, in comparison of mutations and in investigation of early factors which may impact on later severity of Fabry disease are given.This validated age and gender adjusted scoring system allows the comparison of disease severity in different subgroups such as genotypes without age or sex as confounding factors. © 2010 Elsevier Inc. Source


Hughes D.A.,Lysosomal Storage Disorders Unit | Pastores G.M.,New York University
Wiener Medizinische Wochenschrift | Year: 2010

Gaucher disease is a genetic disorder of sphingolipid metabolism resulting from dysfunction of the lysosomal membrane-associated glycoprotein glucocerebrosidase (GBA) and resulting in intracellular accumulation of glucosylceramide and other glycolipids. Although the gene defect and relevant biochemical pathways have been defined, the mechanisms by which substrate accumulation causes disease manifestations are not well understood. The direct effects of a build up of substrate laden cells may account for some aspects of disease but the overall pathology is likely to be more complex with effects of stored material on a variety of intra and extra cellular functions. In this article we review the GBA gene and its protein product, with associated defects, lipid metabolism and storage, enzyme misfolding and endoplasmic reticulum stress, calcium homeostasis, oxidative stress and autophagy and at each point examine how therapies that are currently available, in clinical development or at earlier stages of basic research might address the pathological mechanisms. © 2010 Springer-Verlag. Source


Alharbi F.J.,University of Birmingham | Geberhiwot T.,University of Birmingham | Hughes D.A.,Lysosomal Storage Disorders Unit | Ward D.G.,University of Birmingham
Journal of the American Society for Mass Spectrometry | Year: 2016

Fabry disease is an X-linked lysosomal storage disorder caused by deficiency of α-galactosidase A, resulting in the accumulation of glycosphingolipids in various organs. Globotriaosylceramide (Gb3) and its isoforms and analogues have been identified and quantified as biomarkers of disease severity and treatment efficacy. The current study aimed to establish rapid methods for urinary Gb3 extraction and quantitation. Urine samples from 15 Fabry patients and 21 healthy control subjects were processed to extract Gb3 by mixing equal volumes of urine, methanol containing an internal standard, and chloroform followed by sonication and centrifugation. Thereafter, the lower phase was analyzed by MALDI-TOF MS and the relative peak areas of the internal standard and four major species of Gb3 determined. The results showed high reproducibility with intra- and inter-assay coefficients variation of 9.9% and 13.7%, respectively. The limit of detection was 0.15 ng/μL and the limit of quantitation was 0.30 ng/μL. Total urinary Gb3 levels in both genders of classic Fabry patients were significantly higher than in healthy controls (p < 0.0001). Gb3 levels in Fabry males were higher than in Fabry females (p = 0.08). We have established a novel assay for urinary total Gb3 that takes less than 15 min from start to finish. © 2016 The Author(s). Source


Ayto R.M.,Lysosomal Storage Disorders Unit | Hughes D.A.,Lysosomal Storage Disorders Unit | Jeevaratnam P.,Lysosomal Storage Disorders Unit | Rolles K.,University of London | And 4 more authors.
American Journal of Transplantation | Year: 2010

Gaucher disease (GD) is the most prevalent lysosomal storage disorder. Enzyme replacement therapy (ERT) has demonstrable efficacy in reversing clinical and pathological manifestations of GD. We report four patients with GD and severe hepatic impairment who were successfully treated by orthotopic liver transplantation. Liver failure resulted from GD in two patients and due to a comorbidity in two others (HCV and autoimmune chronic active hepatitis). Following successful liver transplantation, patients received long-term ERT. Liver transplantation is a life-saving treatment for end-stage liver disease in patients with Gaucher disease. All four patients have had excellent outcomes from liver transplantation for up to 10 years postprocedure with no evidence of Gaucher-related pathology in the graft. © 2010 The American Society of Transplantation and the American Society of Transplant Surgeons. Source


McNeill A.,University College London | Magalhaes J.,University College London | Shen C.,Bioinformatics Unit | Chau K.-Y.,University College London | And 7 more authors.
Brain | Year: 2014

Gaucher disease is caused by mutations in the glucocerebrosidase gene, which encodes the lysosomal hydrolase glucosylceramidase. Patients with Gaucher disease and heterozygous glucocerebrosidase mutation carriers are at increased risk of developing Parkinson's disease. Indeed, glucocerebrosidase mutations are the most frequent risk factor for Parkinson's disease in the general population. Therefore there is an urgent need to understand the mechanisms by which glucocerebrosidase mutations predispose to neurodegeneration to facilitate development of novel treatments. To study this we generated fibroblast lines from skin biopsies of five patients with Gaucher disease and six heterozygous glucocerebrosidase mutation carriers with and without Parkinson's disease. Glucosylceramidase protein and enzyme activity levels were assayed. Oxidative stress was assayed by single cell imaging of dihydroethidium. Glucosylceramidase enzyme activity was significantly reduced in fibroblasts from patients with Gaucher disease (median 5% of controls, P = 0.0001) and heterozygous mutation carriers with (median 59% of controls, P = 0.001) and without (56% of controls, P = 0.001) Parkinson's disease compared with controls. Glucosylceramidase protein levels, assessed by western blot, were significantly reduced in fibroblasts from Gaucher disease (median glucosylceramidase levels 42% of control, P < 0.001) and heterozygous mutation carriers with (median 59% of control, P < 0.001) and without (median 68% of control, P < 0.001) Parkinson's disease. Single cell imaging of dihydroethidium demonstrated increased production of cytosolic reactive oxygen species in fibroblasts from patients with Gaucher disease (dihydroethidium oxidation rate increased by a median of 62% compared to controls, P < 0.001) and heterozygous mutation carriers with (dihydroethidium oxidation rate increased by a median of 68% compared with controls, P < 0.001) and without (dihydroethidium oxidation rate increased by a median of 70% compared with controls, P < 0.001) Parkinson's disease. We hypothesized that treatment with the molecular chaperone ambroxol hydrochloride would improve these biochemical abnormalities. Treatment with ambroxol hydrochloride increased glucosylceramidase activity in fibroblasts from healthy controls, Gaucher disease and heterozygous glucocerebrosidase mutation carriers with and without Parkinson's disease. This was associated with a significant reduction in dihydroethidium oxidation rate of 50% (P < 0.05) in fibroblasts from controls, Gaucher disease and heterozygous mutation carriers with and without Parkinson's disease. In conclusion, glucocerebrosidase mutations are associated with reductions in glucosylceramidase activity and evidence of oxidative stress. Ambroxol treatment significantly increases glucosylceramidase activity and reduces markers of oxidative stress in cells bearing glucocerebrosidase mutations. We propose that ambroxol hydrochloride should be further investigated as a potential treatment for Parkinson's disease. © 2014 The Author (2014). Published by Oxford University Press on behalf of the Guarantors of Brain. Source

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