Mucopolysaccharidoses table

Understanding of the degradative pathways for GAGs, as in the case of glycoproteins (Chapter 47) and glycosphingohpids (Chapter 24), has been gready aided by elucidation of the specific enzyme deficiencies that occur in certain inborn errors of metabolism. When GAGs are involved, these inborn errors are called mucopolysaccharidoses (Table 48—7). 

Table 48-7. Biochemical defects and diagnostic tests in mucopolysaccharidoses (MPS) and mucolipidoses (ML). ...

The term mucolipidosis was introduced to denote diseases that combined features common to both mucopolysaccharidoses and sphingolipidoses (Chapter 24). Three mucolipidoses are listed in Table 48—7. In sialidosis (mucolipidosis I, ML-I), various oligosaccharides derived from glycoproteins and certain ganglio-sides can accumulate in tissues. I-cell disease (ML-II)... 

Sulfotransferases917 920a transfer sulfo groups to O and N atoms of suitable acceptors (reaction type ID, Table 10-1). Usually, transfer is from the "active sulfate," 3 -phosphoadenosine 5 -phosphosuIfate (PAPS),921 whose formation is depicted in Eq. 17-38. Sulfatases catalyze hydrolysis of sulfate esters. The importance of such enzymes is demonstrated by the genetic mucopolysaccharidoses. In four of these disease-specific sulfatases that act on iduronate sulfate, heparan N-sulfate, galactose-6-sulfate, or N-acetylglu-cosamine-4-sulfate are absent. Some of these, such as heparan N-sulfatase deficiency, lead to severe mental retardation, some cause serious skeletal abnormalities, while others are mild in their effects.922... 

Table 20-1 Lysosomal Storage Diseases Sphingolipidoses and Mucopolysaccharidoses... 

In the clinical disorder known as the mucopolysaccharidoses (caused by accumulation of partially degraded glycosaminoglycans), deformities of the skeleton may occur (Table 49.4). Mental retardation often accompanies these skeletal changes. 

Table D.5. Mucopolysaccharide excretion profile in the various mucopolysaccharidoses...

Laboratory findings are characterized by increased urinary excretion of mucopolysaccharides (Dorfman and Lorincz 1957), with values of 60 mg per liter and more as compared to normal values of 5—10 mg per liter. The urinary mucopolysaccharides in HD consist of chondroitinsulfate B and heparitin sulfate (Dorfman and Lorincz 1957, Meyer et al. 1958) with a 2 1 ratio. The occurrence of both mucopolysaccharides is used for distinction of HD from other mucopolysaccharidoses or other disorders associated with increased mucopolysaccharide excretion, such as the Marfan syndrome (Berenson and Dalferes 1965). The finding of a smaller proportion of heparitinsulfate in HD as compared to the sex-linked mucopolysaccharidosis II (see table 8) (Terry and Linker 1964) is not obligatory. Increased arylsulfatase B activity was found in the urine of patients with HD by Austin et al. (1964). 

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