Activation of hepatic lipase catalyzed phosphatidylcholine hydrolysis by apolipoprotein E.
The effect of apolipoproteins A-I, A-II, C-II, C-III and E on the hydrolysis of phosphatidylcholine and triacylglycerol by hepatic lipase was studied. Hepatic lipase catalyzed phospholipid hydrolysis was 1.8-fold activated by apolipoprotein E while the other apolipoproteins did not affect the hydrolysis by this enzyme. Triacylglycerol hydrolysis by hepatic lipase was 1.5-fold activated by apolipoprotein E while the other apolipoproteins inhibited hepatic lipase. These results suggest that lipoproteins containing apolipoprotein E may be preferred substrates for hepatic lipase.
Thuren
T
T
Department of Biochemistry, Bowman Gray School of Medicine, Winston-Salem, NC 27103.
Sisson
P
P
Waite
M
M
D000818:Animals; D001053:Apolipoproteins / Q000502:physiology; D001057:Apolipoproteins E / Q000502:physiology*; D002384:Catalysis; D004789:Enzyme Activation; D006868:Hydrolysis; D066298:In Vitro Techniques; D008049:Lipase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D010713:Phosphatidylcholines / Q000378:metabolism*; D051381:Rats; D014280:Triglycerides / Q000378:metabolism
D001053:Apolipoproteins; D001057:Apolipoproteins E; D010713:Phosphatidylcholines; D014280:Triglycerides; D008049:Lipase