Arysulfatase and beta-glucuronidase activity in serum in kwashiorkor

Hereditary fructose intolerance mimicking a biochemical phenotype of mucolipidosis: A review of the literature of secondary causes of lysosomal enzyme activity elevation in serum

We describe a patient with failure to thrive, hepatomegaly, liver dysfunction, and elevation of multiple plasma lysosomal enzyme activities mimicking mucolipidosis II or III, in whom a diagnosis of hereditary fructose intolerance (HFI) was ultimately obtained. She presented before introduction of solid foods, given her consumption of a fructose-containing infant formula. We present the most extensive panel of lysosomal enzyme activities reported to date in a patient with HFI, and propose that multiple enzyme elevations in plasma, especially when in conjunction with a normal plasma α-mannosidase activity, should elicit a differential diagnosis of HFI. We also performed a review of the literature on the different etiologies of elevated lysosomal enzyme activities in serum or plasma. © 2016 Wiley Periodicals, Inc.

Liver lysosomal enzymes in rats during long-term dietary restriction. 1. Changes during the developmental period of life

The specific activities of the lysosomal enzymes acid phosphatase, beta-galactosidase, arylsulphatase B and cathepsin D were determined in homogenates of livers of rats fed ad libitum and of rats subjected to long-term dietary restriction (10%, 30% and 50% of diet consumed by the ad libitum group). Dietary restriction began soon after weaning and animals were sacrificed 3, 9, 15 and 24 weeks later. Dietary restriction influenced all four enzymes but the changes depended on the enzyme as well as on the degree and duration of the dietary restriction. Total activity of acid phosphatase increased significantly at 3 weeks of restriction but only in the 50% group. The activity returned to normal values at 9 weeks. Arylsulphatase B increased in all experimental groups with a more pronounced change observed at 3 weeks and in the more severely restricted rats. No notable change in the activities of beta-galactosidase and cathepsin D activities was observed. Changes in the liver ultrastructure paralleled the biochemical changes seen at 3 weeks. Numerous autophagic vacuoles and dense bodies resembling age pigments were formed in the hepatocytic cytoplasm. Mitochondrial enlargement, increased matrical density and rough endoplasmic reticulum fragmentation were also noted. Few of these changes were observed at 9 weeks, and the hepatocyte's morphology was virtually normal at 15 and 24 weeks. The marked changes seen at 3 weeks may be a manifestation of the body's adaptive processes to the nutritional stress.

Changes in lysosomal hydrolase activity associated with malnutrition in young rats

1. Total lysosomal hydrolase activities were measured in liver, gastrocnemius muscle and plasma of malnourished and normal rats between 3 and 8 weeks of age.

2. Concurrently, the DNA and protein contents of the livers and muscles were determined.

3. Increased amounts of acid hydrolase activities were found to be associated with subnormal protein: DNA ratios in the tissues of malnourished rats.

4. It was concluded that lysosomal enzymes may be involved in protein catabolism during malnutrition.