Lipid Droplets Flashcards
What are lipid droplets?
Storage organelles that help to maintain the lipid and energy homeostasis
Structure of lipid droplets?
Composed of hydrophobic core of neutral lipids enclosed by a phospholipid monolayer (surface decorated by number of proteins)
Where do lipid droplets originate?
From the ER and are initiated when neutral lipid are produced
How do neutral lipids come about?
Result from esterification of a fatty acid to triacylglycerol or a sterol (e.g. cholesterol) to a sterol ester
At low concentrations, what happens to neutral lipids?
They are dispersed between the leaflet of the ER bilayer
What happens as the concentrations of neutral lipids increases?
They accumulate
What diseases result from fatty acid storage in lipid droplets being impaired?
Type 2 diabetes and non-alcoholic fatty liver disease
Where are cholesterol ester droplets found?
In the adrenal gland, are a store of cholesterol for steroid hormone production
Where are triacylglycerols and cholesterol esters stored?
In the liver immediately after a meal for release as lipoproteins later
What is hepatosteatosis?
Fatty liver disease - liver takes in more lipids in the diet than it ever needs to release as lipoproteins. Large lipid droplets accumulate in the tissue.
