Evaluation of the apoptotic effect of globotriaosylceramide (Gb3) on normal mononuclear cells: implication for Fabry disease.

ROZENFELD P; DE FRANCESCO P N; FOSSATI C A

Washington

Congreso; The American Society of Human Genetics 60th Annual Meeting; 2010

The American Society of Human Genetics

   Fabry disease is an X-linked lysosomal storage disorder (LSD) due to deficiency of the enzyme alpha-galactosidase A, resulting in intracellular deposition of globotriaosylceramide (Gb3). Plasma Gb3 concentration in Fabry disease patients varies between 2 to 50 μM, while in normal individuals values are below 1,2 μM. In order to analyze a possible pathophysiologic role of Gb3 in Fabry disease, we aim to investigate weather addition of Gb3 on normal cells induces apoptosis. Peripheral blood mononuclear cells (PBMC) from normal control individuals were treated in culture with different concentrations of Gb3 (range: 0 a 40 μM) during different times (0 to 48 hs). Apoptosis levels were analyzed by Annexin V and TUNEL by flow cytometry. Moreover, mithocondrial membrane depolarization by the reagent JC-1 was measured. The treatment of PBMC with Gb3 at different times resulted in an increase of apoptosis, with maximum levels at 6hs. The dose response curve with Gb3 showed a positive effect on apoptosis. These results show a direct effect of pathological Gb3 levels on PBMC. This result would suggest a causal relationship on apoptosis in Fabry disease that could be related to pathophysiology of this disorder.