University of Pennsylvania School of Medicine researchers identified a role for liver enzymes called proprotein convertases and endothelial lipase (EL) in the control of HDL-C levels in mice.
“By and large, the medicines now available lower levels of the bad low-density lipoprotein cholesterol,” says Weijun Jin, M.D., one of the authors of the study. “There is a great need for methods to raise good cholesterol levels. Our findings suggest there may be multiple places to interrupt the metabolism of HDL-C.”
In the current study, the scientists found that treatments that partially block the activity of proprotein convertases decreased plasma HDL-C levels in mice. Further examination showed that the metabolic effect of the proprotein convertases depended on EL, which breaks down HDL-C. Proprotein convertases normally reduces EL function, thus, the loss of proprotein convertase activity leads to an increase in EL and a decline in HDL-C, the team explains. The investigators also showed that increased activity of proprotein convertases in the liver of mice gives a significant boost to HDL