PHSI3012 10-2 Disorders of Lipid Metabolism #2 (T3L2)

Cholesterol is a 26-Carbon sterol lipid that’s synthesised through a complex 37-step process.
It composes 10% 30% 50% 70% 90%( 10%, 30%, 50%, 70%, 90% ) of cell membranes.
Circulating cholesterol arises from the diet as well as from Intracellular Extracellular Intercellular( Intracellular, Extracellular, Intercellular ) synthesis.
It circulates mostly as Cholesterol Ester (cholesterol + FA).

Familial Hypercholesterolaemia is a family of pathologies that range from heterozygous to homozygous. It’s characterised by Increased Decreased( Increased, Decreased ) LDL-Chol HDL-Chol( LDL-Chol, HDL-Chol ) levels. Caused by a loss of LDL-R.

Lysosomal Storage Disease (aka Niemann-Pick disease type C) is a collection of ~50 rare inherited metabolic pathologies. Its hallmark is defective lysosomal function. It’s characterised by Free cholesterol FFA TAG( Free cholesterol, FFA, TAG ) Accumulation Dissipation( Accumulation, Dissipation ) in the lysosome due to the loss of function of NPC1 and/or NPC2.

In cancer, metabolism changes.
De Novo Cholesterol Synthesis AND uptake Synthesis Uptake( Synthesis AND uptake, Synthesis, Uptake ) Increases Decreases( Increases, Decreases );
De Novo Lipid Synthesis AND uptake Synthesis Uptake( Synthesis AND uptake, Synthesis, Uptake ) Increases Decreases( Increases, Decreases ).

Gene Expression of Steroidogenic Enzymes is Increased Decreased( Increased, Decreased ) in CRPC.