Unusual Gangliosidosis in Emu (Dromaius novaehollandiae)

Abstract

A previous study has demonstrated an unusual gangliosidosis in emu that is characterized by the accumulation of gangliosides in the brain tissues with GM3 and GM1 predominating. To provide insight into this unique disorder of emu gangliosidosis, the current study focused on analysis of neutral glycosphingolipids and gangliosides from brain and liver tissues of affected birds and healthy controls. We found not only that the total lipid-bound sialic acid content was increased three-and fourfold in the affected brain and liver, respectively, but also that the ganglioside pattern was rather complex as compared with the control. The absolute ganglioside sialic acid content was significantly increased in the diseased tissues, with the highest elevation levels of GM3 (14-fold) and GM1 (ninefold) in the affected brain. Relative increases in content of these monosialogangliosides were also significant. GM2 was only detected in the affected brain, but not in normal controls. The neutral glycosphingolipid fraction showed accumulation of many oligosylceramides, with six-and 5.5-fold increases in actosylceramide levels for brain and liver, respectively. The level of myelin-associated galactosylceramide (GalCer) in the brain was decreased to only 41 % of that in the healthy control, whereas no difference was found in liver tissues from both groups. Besides GalCer, the brain content of sulfatide (cerebroside-sulfate esters), another myelm-associated glycolipid, decreased to only 16% of the control. The loss of myelin-associated GalCer and sulfatide strongly suggests demyelination in the affected emu brain. Our overall data are consistent with the presence of a unique form of sphingolipidosis in the affected emus, perhaps with secondary demyelination, and suggest a metabolic disorder related to total sphingolipid activator deficiency.

N-Acylated Serinol Is a Novel Ceramide Mimic Inducing Apoptosis in Neuroblastoma Cells

“…For lipid extraction, protein determination, DNA laddering, or enzyme assays, cells were harvested by scraping and pelleted by centrifugation at 300 ϫ g for 5 min. Lipids were prepared and analyzed by HPTLC as described previously (19). HPTLC for ceramide was developed in CHCl 3 /HOAc (9:1, v/v), and staining was performed with 3% cupric acetate in 8% phosphoric acid as described elsewhere (20,21).…”

Pathological and Biochemical Studies of Mucopolysaccharidosis Type IIIB (Sanfilippo Syndrome Type B) in Juvenile Emus (Dromaius novaehollandiae)

“…21 Among avian species, glycogen storage disease II (Pompe disease) in Japanese quail 36 and GM2 gangliosidosis in American flamingo 32,57 have been described. Interestingly, mucopolysaccharidosis (MPS) type IIIB in emus 1,18,45 has been characterized at the molecular level, while a gangliosidosis 4,5,17 and an undetermined LSD 31 in emus have also been suspected based on pathology.…”

Differential Effects of Glycolipid Biosynthesis Inhibitors on Ceramide‐Induced Cell Death in Neuroblastoma Cells

“…Cells resuspended with 1 ml of distilled water were supplemented with 10 ml of CHCl 3 /CH 3 OH (1:1 vol/vol) and the total lipids were extracted as described elsewhere (Freischütz et al, 1997). In brief, the lipid extract was adjusted to the composition of solvent A (CHCl 3 /CH 3 OH/H 2 O, 30 : 60 : 8 by volume) and applied to 1 ml of DEAE‐Sephadex A‐25 for binding of acidic lipids.…”

“…Gangliosides were visualized by spraying with the resorcinol‐HC1 reagent, and neutral lipids were viewed by spraying with 3% cupric acetate in 8% phosphoric acid followed by heating as described elsewhere (Svennerholm, 1957 ; Freischütz et al, 1997). Plates were scanned with a Shimadzu model CS‐91O scanning densitometer at a wavelength of 580 nm, and the relative band intensities were calculated by peak area integration.…”