Methodist Journal

IN THIS ISSUE

Adult Congenital Heart Update

Vol 15, Issue 2 (2019)


FEATURED GUEST EDITOR

ISSUE INTRO

The Growing Number of Adults Surviving with Congenital Heart Disease

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RECOGNITIONS

Drs. MacGillivray and Lin Take the Lead in Adult Congenital Heart Disease

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REVIEW ARTICLES See More

Advanced Cardiac Imaging for Complex Adult Congenital Heart Diseases

149 Fontan Conversions

Anomalous Aortic Origin of a Coronary Artery

Pulmonary Valve Replacement for Tetralogy of Fallot

Management of the Adult with Arterial Switch

Ebstein’s Anomaly

Heart Transplantation in Adults with Congenital Heart Disease

Cholesterol: Can’t Live With It, Can’t Live Without It

CASE REPORTS See More

Simultaneous Transfemoral Mitral and Tricuspid Valve in Ring Implantation: First Case Report with Edwards Sapien 3 Valve

Uneventful Follow-Up 2 Years after Endovascular Treatment of a High Flow Iatrogenic Aortocaval Fistula Causing Pulmonary Hypertension and Right Heart Failure

Device-Related Thrombus: A Reason for Concern?

Retained Coronary Balloon Requiring Emergent Open Surgical Retrieval: An Uncommon Complication Requiring Individualized Management Strategies

MUSEUM OF HMH MULTIMODALITY IMAGING CENTER See More

Do I Look Fat in This? Multimodality Imaging Findings of a Cardiac Lipoma

CLINICAL PERSPECTIVES See More

POINTS TO REMEMBER

The Kidney in Congenital Cyanotic Heart Disease

EXCERPTA

Talking Statins with Antonio Gotto

POINTS TO REMEMBER

Lipids and Renal Disease

EXCERPTA

Addressing the Feedback Loop Between Depression, Diabetes, and Cardiovascular Disease

EDITORIALS

Letter to the Editor in Response to “Cardiac Autonomic Neuropathy in Diabetes Mellitus”

Vol 15, Issue 1 (2019)

Article Abstract

Revisiting Reverse Cholesterol Transport in the Context of High-Density Lipoprotein Free Cholesterol Bioavailability


Article Citation:

Rosales C, Gillard BK, Xu B, Gotto AM Jr, Pownall HJ. Revisiting Reverse Cholesterol Transport in the Context of High-Density Lipoprotein Free Cholesterol Bioavailability. Methodist DeBakey Cardiovasc J. 2019:15(1):47-54.

doi:

Abstract

Dysregulated free cholesterol (FC) metabolism has been implicated in nearly all stages of atherosclerosis, the underlying cause of most cardiovascular disease. According to a widely cited model, the burden of macrophage FC in the arterial wall is relieved by transhepatic reverse cholesterol transport (RCT), which comprises three successive steps: (1) macrophage FC efflux to high-density lipoprotein (HDL) and/or its major protein, apolipoprotein AI; (2) FC esterification by lecithin:cholesterol acyltransferase (LCAT); and (3) HDL-cholesteryl ester (CE) uptake via the hepatic HDL-receptor, scavenger receptor class B type 1 (SR-B1). Recent studies have challenged the validity of this model, most notably the role of LCAT, which appears to be of minor importance. In mice, most macrophage-derived FC is rapidly cleared from plasma (t1/2 < 5 min) without esterification by hepatic uptake; the remainder is taken up by multiple tissue and cell types, especially erythrocytes. Further, some FC is cleared by the nonhepatic transintestinal pathway. Lastly, FC movement among lipid surfaces is reversible, so that a higher-than-normal level of HDL-FC bioavailability—defined by high plasma HDL levels concurrent with a high mol% HDL-FC—leads to the transfer of excess FC to cells in vivo. SR-B1-/- mice provide an animal model to study the mechanistic consequences of high HDL-FC bioavailability that provokes atherosclerosis and other metabolic abnormalities. Future efforts should aim to reduce HDL-FC bioavailability, thereby reducing FC accretion by tissues and the attendant atherosclerosis.

Keywords
free cholesterol bioavailability , reverse cholesterol transport , cholesterol , high density lipoproteins , atherogenesis , lipid metabolism