Sphingolipidoses

sphingolipidoses for under graduate medical students

1. Sphingolipidoses Dr.S.Sethupathy , M.D., Ph.D ., Department of Biochemistry, Rajah Muthiah Medical College, Annamalai University

2. Sphingolipids The sphingolipids a complex range of lipids in which fatty acids are linked via amide bonds to a long-chain base or sphingoid . They are also found in a few bacterial genera - Sphingomonas   and   Sphingobacterium .

3. Globoside

4. PAPS synthase

5. Lysosomal storage diseases The lysosomal storage diseases are a rare class of neurometabolic disorders. Metabolites of complex lipids accumulate within neurons. Mostly autosomal recessive fashion For genetic counseling and for monitoring future pregnancies.

6. Sphingolipidoses They are characterized by a progressive degenerative disease of the nervous system, with blindness, dementia, epilepsy, ataxia, paralysis, and hyperreflexia . A cherry-red spot at the macula and optic atrophy are the most common signs Ophthalmologic examination - an important clue to the diagnosis.

7. Cherry red spot

8. Gangliosides Gangliosides are important constituents of gray matter . They are glycosphingolipids that contain sialic acid in the oligosaccharide chain. The metabolism of ganglioside involves the removal of the terminal galactose to convert G M1 -ganglioside to G M2 -ganglioside. G M2 -ganglioside is then hydrolyzed to G M3 -ganglioside by the removal of N- acetylgalactosamine .

9. D.Blue –GLU, L.Blue - sialic acid, W- NAcGal , Y- Gal

10. Gangliosidoses They are neuronal lipid storage disorders due to deficiencies of certain lysosomal hydrolases . Autosomal recessive inheritance Progressive mental and motor deterioration Due to the storage of G M1 - or G M2 -ganglioside in neurons.

11. Prognosis Lysosomal storage diseases are ultimately fatal There is no effective treatment . Almost all the disorders diagnosed by enzyme analysis . Leukocytes and cultured skin fibroblasts or serum can be assayed for enzyme activity Prenatal diagnosis is also possible.

12. Thank you