BACKGROUND AND PURPOSE Metachromatic leukodystrophy (MLD) is a devastating demyelinating disease for which novel therapies are being tested. We hypothesized that MR imaging of brain lesion involvement in MLD could be quantified along a scale. MATERIALS AND METHODS Thirty-four brain MR images in 28 patients with proved biochemical and genetic defects for MLD were reviewed: 10 patients with lat...

Activity and kinetics of arylsulfatase A (ASA, EC 3.1.6.8) were analyzed in leukocyte homogenates derived from patients suffering from cerebral palsy. Lower ASA activity was found in the patients' leukocytes than in controls, as determined by spectrophotometry using chromogenic substrate p-nitrocatechol sulfate (p-NCS). Kinetic parameters, K(m) and v(max), for leukocyte ASA were determined from...

Hariharasubramanian Ramakrishnan,1* Kerstin Khalaj Hedayati,2* Renate Lüllmann-Rauch,2 Carsten Wessig,3 Simon Ngamli Fewou,1 Helena Maier,1 Hans-Hilmar Goebel,4 Volkmar Gieselmann,1 and Matthias Eckhardt1 1Institute of Physiological Chemistry, Rheinische Friedrich-Wilhelms University of Bonn, 53115 Bonn, Germany, 2Institute of Anatomy, Christian-Albrechts University of Kiel, 24098 Kiel, Germany...

Molecular alterations associated with arylsulfatase A pseudodeficiency (ASA-PD) were characterized by PCR and restriction endonuclease analysis in a sample of healthy individuals from Brazil. ASA activity was also assayed in all subjects. Two individuals homozygous for the N350S and 1524+95A<--G mutations were detected, corresponding to a frequency of 1.17% (4 of 324 alleles). The individual fr...

Saposin B (SapB) is a human lysosomal protein, critical for the degradation of O-sulfogalactosylceramide (sulfatide). SapB binds sulfatide and presents it to the active site of the enzyme arylsulfatase A. Deficiency of SapB leads to fatal activator-deficient metachromatic leukodystrophy. Given the conformational flexibility and the large hydrophobic "pocket" produced upon (physiologically relev...

Metachromatic leukodystrophy (MLD) is a lysosomal storage disorder caused mainly by mutations in the arylsulfatase A (ARSA) gene. In this manuscript we report sixteen novel mutations identified in the ARSA gene of fifteen unrelated patients affected with MLD. Of these 16 mutations nine were missense mutations (p.L11Q, p.S44P, p.L81P, p.R84L, p.V177D, p.P284S, p.R288S, p.G301R, p.P425S), three w...

A deficiency of the lysosomal enzyme arylsulfatase A (ASA) causes the lysosomal storage disorder metachromatic leukodystrophy (MLD). The diagnosis of MLD is straightforward in cases with deficient leukocyte or fibroblast ASA activity and a typical clinical history. However, several atypical and late-onset forms of MLD have been described. The diagnosis is also complicated by the high frequency ...

Fibroblasts cultured from the skin of a patient with metachromatic leukodystrophy have been found to manifest the biochemical defect of this inborn error of metabolism, a deficiency of arylsulfatase A. Diseased cells had less than five per cent of normal arylsulfatase-A activity, while activities of other lysosomal enzymes-including arylsulfatase B, beta-galactosidase, beta-glucuronidase, and b...