Regional Central Nervous System Oligosaccharide Storage in Caprine ?-Mannosidosis

Publisher Website
Google Scholar
Abstract
Goats affected with .beta.-mannosidosis, an autosomal recessive disease of glycoprotein metabolism, have deficient activity of the lysomoal enzyme .beta.-mannosidase along with tissue storage of oligosaccharides, including a trisaccharide [Man(.beta.1-4)GlcNAc(.beta.1-4)GlcNAc] and a disaccharide [Man(.beta.1-4)GlcNAc]. CNS myelin deficiency, with regional variation in severity, is a major pathological characteristic of affected goats. This study was designed to investigate regional CNS differences in oligosaccharide accumulation to assess the extent of correlation between oligosaccharide accumulation and severity of myelin deficits. The concentrations of accumulated disaccharide and trisaccharide and the activity of .beta.-mannosidase were determined in cerebral hemisphere gray and white matter and in spinal cord from three affected and two control neonatal goats. In affected goats, the content of trisaccharide and disaccharide in spinal cord (moderate myelin deficiency) was similar to or greater than that in cerebral hemispheres (severe myelin deficiency). Thus, greater oligosccharide accumulation was not associated with more severe myelin deficiency. Regional .beta.-mannosidase activity levels in control goats were consistent with the affected goat oligosaccharide accumulation pattern. The similarity of trisaccharide and disaccharide content in cerebral hemisphere gray and white matter suggested that lysosomal storage vacuoles, more numerous in gray matter, may not be the only location of stored CNS oligosaccharides.