Diseases associated with impaired lipid metabolism

Disturbance of lipid metabolism can occur at the level of their splitting, absorption, transport, and intermediate metabolism. There are two main types of hereditary disturbances in the metabolism of lipids.

■ Lipidosis, or sphingolipidosis, leading to accumulation of sphingo-lipids in cells of different tissues( intracellular lipidases).

■ Diseases with impaired metabolism of LPs contained in the blood( familial hypercholesterolemia, etc.).

Most of the disorders associated with the accumulation of sphingolipids in cells of different tissues are due to the insufficiency of lysosomal enzymes involved in the exchange of sphingolipids, especially in the process of their disintegration. In Table.the main diseases caused by hereditary insufficiency of lysosomal hydro-las are given. Most often observed diseases of Niemann-Pick, Gaucher and Thea-Saks.

The Niemann-Pick disease is caused by the accumulation of sphingomyelin in the brain, liver, reticuloendothelial system. The disease is caused by sphingomyelinase deficiency. Type of inheritance is autosomal recessive. There are 4 types of Niemann-Pick disease( A-D).Type A manifests itself as a severe lesion of the nervous system, leading to a fatal outcome during the first 2-3 years of life. In the forms of B-D, hepatocytes are predominantly affected, which causes a longer life span. Data on the location of mutations in chromosomes and their possible variants are given in Table.

Table Molecular-genetic bases of sphingolipidoses

Table Molecular-genetic bases of sphingolipidoses

Gauchers disease is manifested by accumulation in the brain, liver, bone marrow and spleen of cerebrosides. At the heart of the disease is insufficiency of p-glucosidase( glucocerebrosidase).

The disease of Thea-Saks( Gangliosidosis GM2 type 1) is caused by accumulation in the brain, liver and spleen cells of the gangliosides due to insufficiency of hexoaminidase A. The disease develops slowly, therefore in the first 3-4 months of life, children do not differ from healthy peers. Then gradually the child becomes less active, there are disorders of vision and hearing. Mental disorders progress to idiocy, the disease ends lethal. For diagnostics, the activity of hexoaminidase A.