Gaucher disease, the inherited deficiency of lysosomal
glucocerebrosidase, presents with a wide spectrum of clinical manifestations including neuronopathic and non-neuronopathic forms. While the
lipid glucosylceramide is stored in both patients with
Gaucher disease and in a null allele mouse model of
Gaucher disease, elevated levels of a second potentially toxic substrate,
glucosylsphingosine, are also found. Using high performance liquid chromatography,
glucosylsphingosine levels were measured in tissues from patients with type 1, 2, and 3
Gaucher disease.
Glucosylsphingosine was measured in 16 spleen samples (8 type 1; 4 type 2; and 4, type 3) and levels ranged from 54 to 728 ng/mg
protein in the patients with type 1 disease, 133 to 1200 ng/mg
protein in the patients with type 2, and 109 to 1298 ng/mg
protein in the type 3 samples. The levels of splenic
glucosylsphingosine bore no relation to the type of
Gaucher disease, the age of the patient, the genotype, nor the
clinical course. In the same patients, hepatic
glucosylsphingosine levels were lower than in spleen.
Glucosylsphingosine was also measured in brains from 13 patients (1 type 1; 8 type 2; and 4 type 3). While the
glucosylsphingosine level in the brain from the type 1 patient, 1.0 ng/mg
protein, was in the normal range, the levels in the type 3 samples ranged from 14 to 32 ng/mg
protein, and in the type 2 samples from 24 to 437 ng/mg
protein, with the highest values detected in two fetuses with
hydrops fetalis. The elevated levels found in brains from patients with neuronopathic
Gaucher disease support the hypothesis that
glucosylsphingosine may contribute to the nervous system involvement in these patients.