Oligosaccharide excretion in adult Gaucher disease

Abstract

Gaucher disease is a lysosomal storage disease characterized by storage of glucocerebroside due to lysosomal glucocerebrosidase deficiency. Increased urinary excretion of sialyloligosaccharides and mannosylglycoasparagines has been described for two patients with the infantile form of the disease, probably as a consequence of obstruction of lysosomal functioning due to the glycolipid accumulation in lysosomes. By thin-layer chromatography, we found increased urinary oligosaccharide excretion in a series of adult non-neuronopathic patients. Oligosaccharide patterns were comparable between patients and also with the pattern observed in infantile Gaucher disease. Composition was analysed by methanolysis and gas chromatography. Mannose and N-acetylglucosamine are the main carbohydrates in all oligosaccharide bands. A statistically significant correlation was found between oligosaccharide excretion and the severity of the disease expressed as severity score index. Patients treated with enzyme replacement therapy showed a reduction up to 65% of the original oligosaccharide excretion after 1 year of treatment, comparable with the reduction in spleen volume.

Quantitation of Proteoglycans as Glycosaminoglycans in Biological Fluids Using an Alcian Blue Dot Blot Analysis

“…Because of such matrix effects, the dye binding methods have been modified with regard to pH or ionic strength to either decrease (1,6,10,12,13) or increase (14) the negative interference seen in biological fluids. By decreasing pH below the pK a of carboxyles, the positive interference by hyaluronic acid and proteins may be lowered.…”

“…The reason is that the positively charged proteins compete favorably with the dye for binding to the GAGs, at low ionic strengths. By increasing pH, the negative interference by proteins binding to GAGs will disappear (13), but positive interference with dye binding to carboxyl groups on proteins and hyaluronic acid as well as phosphoric acid groups on nucleic acids will increase.…”

“…Glycosaminoglycans in the urine may be derived from plasma molecules filtered in the kidney or from proteoglycans synthesized in the kidney or urinary tract tissues. Measurement of urinary GAGs is clinically useful for diagnosis of mucopolysaccharidoses (13,21).…”

“…Dye binding assays are subject to positive or negative interference (6,9,10,12,13,20), that will either increase or decrease the color yield in biological samples. The extent of positive or negative interference with plasma is easily tested, but seldom published.…”

Carbohydrates

“…DeJong et al (110) used TLC with silica gel 60 plates to detect oligosaccharides in urine as a measure of the severity of Gaucher's disease and preparative TLC prior to analysis of the sugar composition of urine by gas chromatography. Kimber et al (77a) used HPTLC to compare the glycosphingolipid composition of untreated and retinoic acid-treated embryonic stem cells and preparative HPTLC to purify glycolipids prior to fast atom bombardment mass spectrometry.…”