Determination of globotriaosylceramide analogs in the organs of a mouse model of Fabry disease

Abstract

Fabry disease is a heritable lipid disorder caused by the low activity of α-galactosidase A and characterized by the systemic accumulation of globotriaosylceramide (Gb3). Recent studies have reported a structural heterogeneity of Gb3 in Fabry disease, including Gb3 isoforms with different fatty acids and Gb3 analogs with modifications on the sphingosine moiety. However, Gb3 assays are often performed only on the selected Gb3 isoforms. To precisely determine the total Gb3 concentration, here we established two methods for determining both Gb3 isoforms and analogs. One was the deacylation method, involving Gb3 treatment with sphingolipid ceramide N-deacylase, followed by an assay of the deacylated products, globotriaosylsphingosine (lyso-Gb3) and its analogs, by ultra-performance LC coupled to tandem MS (UPLC-MS/MS). The other method was a direct assay established in the present study for 37 Gb3 isoforms and analogs/isoforms by UPLC-MS/MS. Gb3s from the organs of symptomatic animals of a Fabry disease mouse model were mainly Gb3 isoforms and two Gb3 analogs, such as Gb3(+18) containing the lyso-Gb3(+18) moiety and Gb3(−2) containing the lyso-Gb3(−2) moiety. The total concentrations and Gb3 analog distributions determined by the two methods were comparable. Gb3(+18) levels were high in the kidneys (24% of total Gb3) and the liver (13%), and we observed Gb3(−2) in the heart (10%) and the kidneys (5%). These results indicate organ-specific expression of Gb3 analogs, insights that may lead to a deeper understanding of the pathophysiology of Fabry disease.

Fabry disease pain: patient and preclinical parallels

“…In an effort to improve the model, the Fabry mouse was crossbred with a Gb3 synthase-overexpressing mouse to increase the accumulation of Gb3 throughout the mouse. 93 , 195 This mouse has a greatly shortened lifespan and severe pathology unlike what is observed in patients and has not been used to study pain behaviors. 195 …”

Enfermedad de Fabry clásica en pacientes pediátricos asintomáticos

“…Palavras-chave: doença de Fabry; doença de Fabry em crianças; terapia enzimática; bioética Introducción La enfermedad de Fabry es un error innato del catabolismo de glucoesfingolípidos, ligado al cromosoma X, debido a la deficiencia en la actividad de la exoglucohidrolasa α-galactosidasa A (α-Gal A) lisosomal (1), lo que genera la acumulación sistemática de globotriaosilceramida (GL3) y glucoesfingolípidos (gsl), principalmente en los lisosomas del endotelio vascular y en el plasma (2). Por esto se considera que esta enfermedad es una endoteliopatía de origen enzimático, con compromiso multisistémico.…”

“…Revista Latinoamericana de Bioética ■ Vol. 20 (1) Evaluación de la aplicación del principio de justicia La pregunta 11 permitió también evaluar en cuanto a la toma de decisión terapéutica que el 83,33 % de los médicos encuestados respondió afirmativamente. Solo dos médicos neuropediatras escogieron la opción "No" (16,66 %).…”

Distinctive accumulation of globotriaosylceramide and globotriaosylsphingosine in a mouse model of classic Fabry disease

“…The presence of Gb3 isoforms and two lyso-Gb3 analogs {lyso-Gb3(−2) and lyso-Gb3(+18)} has been described in GLA -knockout mice [ 16 ]. We established a deacylation method for the total Gb3 concentration and the distribution of Gb3 analogs, and reported an organ-specific distribution of Gb3 isoforms and analogs/isoforms in our FD model Gla tm Tg(CAG-A4GALT) mice, whereby Gb3(+18) levels were high in the kidneys and liver, while Gb3(−2) levels were increased in the heart [ 17 ]. This technique is useful for the characterization of plasma Gb3 and lyso-Gb3.…”