Figure 2. Pathways of HDL cholesterol uptake by the liver.

HDL-CE and HDL free cholesterol can be directly and selectively taken up by the liver via SR-BI. Alternatively, HDL-CE can be transferred to apoB-containing lipoproteins by CETP and then taken up by liver via the LDLR. In the hepatocyte, CE is hydrolyzed to free cholesterol, which is either excreted directly into the bile or converted to bile acid (BA) and excreted into the bile.