Croatian population data for arylsulfatase a pseudodeficiency-associated mutations in healthy subjects, and in patients with Alzheimer-type dementia and Down syndrome.

Background: Arylsulfatase A (ASA) is a lysosomal enzyme involved in catabolism of cerebroside sulfate, whose deficiency causes metachromatic leukodystrophy, a rare autosomal recessive disorder characterized by storage of cerebroside sulfate, mainly in the nervous system. Low ASA activities have also been reported in healthy individuals and several neuropsychiatric disorders due to the condition termed ASA pseudodeficiency. The aim of this study was to establish frequency of two mutations associated with ASA pseudodeficiency in healthy individuals in the Croatian population as well as in persons with Alzheimer-type dementia and Down syndrome.

Leukocyte lysosomal enzymes in Alzheimer's disease and Down's syndrome.

Previous studies suggested the possibility of accelerated lysosomal degradation of brain gangliosides in Alzheimer's disease (AD). As AD pathology affects both neural and nonneural tissues, the aim of this study was to determine possible changes of glycosphingolipid metabolism in available peripheral cells in AD and Down's syndrome (DS). The activities of several lysosomal enzymes involved in catabolism of gangliosides and sulfatides were measured in leukocytes from subjects with dementia of the Alzheimer type, DS, and age-matched controls, by fluorimetry and spectrophotometry using specific substrates.