187 - Effects of HDL triglyceride enrichment on reverse cholesterol transport in dyslipidemic patients (ID 894)
Abstract
Background and Aims
We recently reported that high HDL triglycerides (HDL-TG) levels are an additional factor to explain the cardiovascular risk associated with high triglycerides. As a key function of HDL is to promote reverse cholesterol transport from the periphery to the liver, we aimed to analyse the effects of HDL-TG on cholesterol transport in patients at high cardiovascular risk.
Methods
HDL were isolated by sequential ultracentrifugation in 28 dyslipidemic patients from the University Hospital Lipid Unit. Cholesterol efflux capacity and cholesterol uptake was analyzed using a fluorescent sterol (boron dipyrromethene difluoride linked to sterol carbon-24, BODIPY-cholesterol) in J774 macrophages and HEPG2 cells, respectively.
Results
We studied the HDL-mediated cholesterol efflux capacity from macrophages at growing concentrations of HDL cholesterol (5-250 µg/mL) and we observed a dose-response efflux capacity. Patients were grouped according to low- or high-HDL-TG (5.36±1.03 mg/dL; 19.79±4.26 mg/dL, respectively). We observed that patients with high levels of HDL-TG had a significant increase in both cholesterol efflux (4.79%, P=0.0019) and cholesterol uptake (2.98%, P<0.0001) compared to patients with low HDL-TG.
Conclusions
Reverse cholesterol transport is not aggravated in patients with higher HDL-TG levels. Alterations in other HDL biological functions could contribute to increased cardiovascular risk in hypertriglyceridemia.
