1,2-diacylglycerols
1,2-diacyl- sn -glycerine [also simply diacylglycerols (DAG) ] are naturally occurring chemical compounds of glycerol with sn-configuration , namely the fatty acid - ester with the fatty acids caproic acid , oleic acid , palmitic acid , arachidonic acid or stearic acid . They are intermediate products in the biosynthesis of triglycerides and products of the cleavage of the membrane lipid phosphatidylinositol-4,5-bisphosphate (PIP 2 ) by phospholipase C (PLC). DAGs generally belong to the diglycerides .
1,2-Diacyglycerols are often used in second messenger systems. They recruit enzymes to the cell membrane and anchor them there.
Among other things, they are involved in the activation of protein kinase C (PKC) and Munc 13-1. The protein kinase C then phosphorylates enzymes in the cytosol and thus influences gene expression. Munc 13-1 is a protein that plays a role in the release of transmitters into the synaptic cleft.
Importance in medicine
In patients with diabetes mellitus, increased blood sugar levels lead to an increase in the diacylglycerol concentration in the cell and thus to an activation of protein kinase C. This promotes the production of extracellular matrix and cytokines , increases the contractility and permeability ( permeability ) of blood vessels, increases this Cell growth in blood vessels , activates phospholipase A2 and inhibits Na + / K + -ATPase . The result is vascular damage to the retina of the eye , the kidney and the heart .