Glycosphingolipid depletion in fabry disease lymphoblasts with potent inhibitors of glucosylceramide synthase.
BACKGROUND
Fabry disease is an inherited X-linked disorder resulting in the loss of activity of the lysosomal hydrolase alpha-galactosidase A and causing the clinical manifestations of renal failure, cerebral vascular disease, and myocardial infarction. The phenotypic expression of this disorder is manifest by the accumulation of glycosphingolipids containing alpha-galactosyl linkages, most prominently globotriaosylceramide.


METHODS
Based on quantitative structure activity studies, we recently reported two newly designed glucosylceramide synthase inhibitors based on 1-phenyl-2-palmitoylamino-3-pyrrolidino-1-propanol (P4). These inhibitors, 4'-hydroxy-P4 and ethylenedioxy-P4, were evaluated for their ability to deplete globotriaosylceramide and other glucosylceramide-based lipids in Fabry lymphocytes and were compared with N-butyldeoxynojirimycin, another reported glucosylceramide synthase inhibitor.


RESULTS
Concentrations as low as 10 nmol/L of 4'-hydroxy-P4 and ethylenedioxy-P4 resulted in 70 and 80% depletion, respectively, of globotriaosylceramide, with maximal depletion occurring at three days of treatment. There was no impairment of cell growth. In contrast, N-butyldeoxynojirimycin only minimally lowered globotriaosylceramide levels, even at concentrations as high as 10 micromol/L. Globotriaosylceramide depletion was confirmed by the loss of binding of FITC-conjugated verotoxin B subunit to the lymphoblasts.


CONCLUSIONS
These findings suggest that selective glucosylceramide synthase inhibitors are highly effective in the depletion of globotriaosylceramide from Fabry cell lines. We suggest that these compounds have potential therapeutic utility in the treatment of Fabry disease.
Abe
A
A
Nephrology Division, Department of Internal Medicine and Department of Pathology, University of Michigan Medical Center, Ann Arbor, MI 48109-0676, USA.
Arend
L J
LJ
Lee
L
L
Lingwood
C
C
Brady
R O
RO
Shayman
J A
JA
D017485:1-Deoxynojirimycin / Q000031:analogs & derivatives / Q000494:pharmacology; D001402:B-Lymphocytes / Q000166:cytology / Q000201:enzymology*; D001427:Bacterial Toxins; D002461:Cell Line, Transformed; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D000795:Fabry Disease / Q000188:drug therapy / Q000276:immunology / Q000378:metabolism*; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D005822:Genetic Vectors; D005964:Glucosyltransferases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D006028:Glycosphingolipids / Q000032:analysis; D004854:Herpesvirus 4, Human; D006801:Humans; D020383:Neutral Glycosphingolipids / Q000032:analysis / Q000378:metabolism*; D011412:Propanolamines / Q000737:chemistry / Q000494:pharmacology*; D011759:Pyrrolidines / Q000737:chemistry / Q000494:pharmacology*; D022622:Shiga Toxin 1; D014281:Trihexosylceramides / Q000096:biosynthesis*; D000519:alpha-Galactosidase / Q000378:metabolism
C404730:3',4'-ethylenedioxyphenyl-2-palmitoylamino-3-pyrrolidino-1-propanol; C404731:4'-hydroxy-1-phenyl-2-palmitoylaminio-3-pyrrolidino-1-propanol; D001427:Bacterial Toxins; D004791:Enzyme Inhibitors; D005456:Fluorescent Dyes; D006028:Glycosphingolipids; D020383:Neutral Glycosphingolipids; D011412:Propanolamines; D011759:Pyrrolidines; D022622:Shiga Toxin 1; D014281:Trihexosylceramides; C013869:ceramide dihexoside; C088880:ceramide trihexoside; D017485:1-Deoxynojirimycin; C018549:globotriaosylceramide; C059896:miglustat; D005964:Glucosyltransferases; C023246:ceramide glucosyltransferase; D000519:alpha-Galactosidase; D016650:Fluorescein-5-isothiocyanate