ATP Synthase β-Chain Overexpression in SR-BI Knockout Mice Increases HDL Uptake and Reduces Plasma HDL Level

Abstract EN

HDL cholesterol is known to be inversely correlated with cardiovascular disease due to its diverse antiatherogenic functions.

SR-BI mediates the selective uptake of HDL-C.

SR-BI knockout diminishes but does not completely block the transport of HDL; other receptors may be involved.

Ectopic ATP synthase β-chain in hepatocytes has been previously characterized as an apoA-I receptor, triggering HDL internalization.

This study was undertaken to identify the overexpression of ectopic ATP synthase β-chain on DIL-HDL uptake in primary hepatocytes in vitro and on plasma HDL levels in SR-BI knockout mice.

Human ATP synthase β-chain cDNA was delivered to the mouse liver by adenovirus and GFP adenovirus as control.

The adenovirus-mediated overexpression of β-chain was identified at both mRNA and protein levels on mice liver and validated by its increasing of DiL-HDL uptake in primary hepatocytes.

In response to hepatic overexpression of β-chain, plasma HDL-C levels and cholesterol were reduced in SR-BI knockout mice, compared with the control.

The present data suggest that ATP synthase β-chain can serve as the endocytic receptor of HDL, and its overexpression can reduce plasma HDL-C.