Quantitative evaluation of sphingomyelin and glucosylceramide using matrix-assisted laser desorption ionization time-of-flight mass spectrometry with sphingosylphosphorylcholine as an internal standard. Practical application to tissues from patients with Niemann-Pick disease types A and C, and Gaucher disease.

Niemann-Pick disease types A and C, and Gaucher disease are glycolipid storage disorders characterized by the systemic deposition of glycosphingolipids, i.e., sphingomyelin in Niemann-Pick disease types A and C tissues and glucosylceramide in Gaucher disease ones, respectively. Using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF/MS), we analyzed the sphingolipids in liver and spleen specimens from patients with Niemann-Pick disease types A and C, and Gaucher disease. Crude lipids were extracted from tissue containing 5mg protein with chloroform and methanol. After mild alkaline treatment of the crude lipids, a sphingolipid fraction was prepared and analyzed by MALDI-TOF/MS. The results were as follows: (a) ion peaks with m/z values corresponding to different sphingomyelin and ceramide monohexoside (CMH) species were clearly detected. (b) With sphingosylphosphorylcholine as the internal standard for quantification of sphingomyelin and CMH, the relative peak heights of sphingomyelin and CMH were calculated and plotted versus their contents. The relative peak heights of sphingomyelin and CMH showed linearity between 50 and 1500 ng sphingomyelin content, and between 5 and 150 ng CMH content, respectively. (c) Quantitative analysis revealed the accumulation of sphingomyelin in the liver and spleen specimens from the patients with Niemann-Pick disease types A and C. Striking accumulation of CMH was also detected in the liver and spleen specimens from the patients with Gaucher disease. This investigation indicated that accumulated sphingomyelin and CMH in small amounts of tissues from sphingolipidosis patients can be detected quantatively with the MALDI-TOF/MS method. This method will be useful not only for the diagnosis but also for biochemical pathophysiology evaluation of patients with various sphingolipidosis.

Quantitative evaluation of sphingolipids using delayed extraction matrix-assisted laser desorption ionization time-of-flight mass spectrometry with sphingosylphosphorylcholine as an internal standard. Practical application to cardiac valves from a patient with Fabry disease.

Fabry disease is a glycolipid storage disorder caused by a defect of alpha-galactosidase A, and characterized by the systemic deposition of glycosphingolipids with terminal alpha-galactosyl moieties, mainly globotriaosylceramide, in tissues. Using delayed extraction matrix-assisted laser desorption ionization time-of-flight mass spectrometry (DE MALDI-TOF-MS), we analyzed the sphingolipids in the cardiac valves from a 49-year-old male patient with Fabry disease who suffered from congestive cardiac failure. Crude lipids were extracted from the cardiac valves with chloroform and methanol. After mild alkaline treatment of the crude lipids, a sphingolipid fraction was prepared and analyzed by DE MALDI-TOF-MS. The results were as follows: (a) ion peaks with m/z values corresponding to different ceramide trihexoside (CTH) species were detected; (b) with sphingosylphosphorylcholine (SPC) as the internal standard for semi-quantification of CTH, the relative peak height of CTH was calculated and plotted versus its amount loaded on the sample plate for MALDI-TOF-MS. The relative peak height of CTH with fatty acid C16:0 showed linearity between 0 and 50 ng CTH (regression coefficient, r>0.95); (c) semi-quantitative analysis revealed striking accumulation of CTH in the cardiac valves from the patient with Fabry disease. It was indicated that the accumulation of CTH in cardiac valves from Fabry disease patients can be detected with the DE MALDI-TOF-MS method. SPC is commercially available, and this semi-quantitative method involving MALDI-TOF-MS was found to be convenient, reliable and useful for CTH. It is expected to be applied to the quantification of CTH in small amounts of body fluids or other tissues and to clinical examination. It is also expected to be applicable to the quantification of other glycosphingolipids.

Brain stem glioblastoma with multiple large cyst formation and leptomeningeal dissemination in a 4-year-old girl.

The authors report a 4-year-old girl who developed brain stem glioblastoma. Meningeal irritation was present at onset. Magnetic resonance imaging revealed intracranial and intraspinal leptomeningeal dissemination, which progressed faster than the original tumor. Multiple large cysts developed at the interhemispheric and prepontine cisterns, resulting in progressive obstructive hydrocephalus. The patient survived only 5 months after presentation. Histology was verified by autopsy.

Application of delayed extraction-matrix-assisted laser desorption ionization time-of-flight mass spectrometry for analysis of sphingolipids in pericardial fluid, peritoneal fluid and serum from Gaucher disease patients.

Gaucher disease is a glycolipid storage disorder characterized by the accumulation of glucosylceramide. Using delayed extraction matrix-assisted laser desorption ionization time-of-flight mass spectrometry (DE-MALDI-TOF-MS), we analyzed sphingolipids in pericardial fluid, peritoneal fluid, and serum from two patients with Gaucher disease. Crude lipids were extracted from 1 ml each of pericardial fluid, peritoneal fluid, and serum with chloroform and methanol. After mild alkaline treatment of the crude lipids, a sphingolipid fraction was prepared and analyzed by DE-MALDI-TOF-MS. The results were as follows: (a) in all the specimens, peaks of ceramide monohexoside and sphingomyelin were detected in both the controls and Gaucher disease patients; (b) in pericardial fluid, peritoneal fluid, and serum, the ceramide monohexoside/sphingomyelin ratio was increased in the Gaucher disease patients compared with in the controls. It was indicated that the accumulation of ceramide monohexoside in such samples from Gaucher disease patients can be easily detected with this DE-MALDI-TOF-MS method.

Evaluation of sphingolipids in vitreous bodies from a patient with Gaucher disease, using delayed extraction matrix-assisted laser desorption ionization time-of-flight mass spectrometry.

Gaucher disease is a glycolipid storage disorder characterized by the accumulation of glucosylceramide in tissues. Using delayed extraction matrix-assisted laser desorption ionization time-of-flight mass spectrometry (DE MALDI-TOF-MS), we analyzed sphingolipids in vitreous bodies from a patient with Gaucher disease who suffered from vitreous opacities. Crude lipids were extracted from the freeze-dried vitreous bodies with chloroform and methanol. After mild alkaline treatment of the crude lipids, a sphingolipid fraction was prepared and analyzed by DE MALDI-TOF-MS. The results were as follows: (a). the m/z values of the ions found in the mass spectra for both the control and the Gaucher disease patient corresponded to different sphingomyelin species. (b). The mass spectrum of the Gaucher disease patient showed additional ions with m/z values corresponding to different ceramide monohexoside (CMH) species. It was indicated that the accumulation of CMH in vitreous bodies from Gaucher disease patients could be easily detected with the DE MALDI-TOF-MS method.

Hemiconvulsion-hemiplegia syndrome and elevated interleukin-6: case report.

We report a 2-year-old boy who developed hemiconvulsion-hemiplegia syndrome with left-sided hemiplegia after a seizure lasting 35 minutes. The interleukin-6 level in the cerebrospinal fluid 2 hours after seizure onset was elevated to levels seen in patients with encephalitis. At 1 year after onset of the seizure, the patient remained hemiplegic on the left side, and magnetic resonance imaging showed severe right hemispheric atrophy. Acute changes seen on imaging studies and electroencephalograms in this patient were consistent with seizure-induced brain damage. Elevation of cerebrospinal fluid interleukin-6 may be related to the severe neurologic sequelae of our patient despite the relatively short seizure duration.