Red Blood Cells Play a Role in Reverse Cholesterol Transport

Abstract

Objective Reverse cholesterol transport (RCT) involves the removal of cholesterol from peripheral tissue for excretion in the feces. Here, we determined whether red blood cells (RBCs) can contribute to RCT. Methods and Results We performed a series of studies in apoAI-deficient mice where the HDL-mediated pathway of RCT is greatly diminished. RBCs carried a higher fraction of whole blood cholesterol than plasma in apoAI-deficient mice, and as least as much of the labeled cholesterol derived from injected foam cells appeared in RBCs compared to plasma. To determine if RBCs mediate RCT to the fecal compartment, we measured RCT in anemic and control apoAI-deficient mice and found that anemia decreased RCT to the feces by over 35% after correcting for fecal mass. Transfusion of [3H]cholesterol labeled RBCs led to robust delivery of the labeled cholesterol to the feces in apoAI-deficient hosts. In wild type mice, the majority of the blood cholesterol mass, as well as [3H]cholesterol derived from the injected foam cells, was found in plasma, and anemia did not significantly alter RCT to the feces after correction for fecal mass. Conclusion The RBC cholesterol pool is dynamic and facilitates RCT of peripheral cholesterol to the feces, particularly in the low HDL state.

Serum albumin acts as a shuttle to enhance cholesterol efflux from cells

“…A particularly important cholesterol pool that could be infl uenced by the shuttling capability of albumin is RBC cholesterol. The cholesterol concentration of RBC is roughly equivalent to that found in plasma lipoproteins ( 34 ), and it has been recently shown that RBC plays a role in reverse cholesterol transport ( 34 ). FC in the membrane of RBC rapidly exchanges with other pools of cholesterol via an aqueous diffusion mechanism (35)(36)(37).…”

“…FC in the membrane of RBC rapidly exchanges with other pools of cholesterol via an aqueous diffusion mechanism (35)(36)(37). Thus, both the fl ux of cholesterol between plasma lipoproteins and RBC, as well as the delivery of RBC cholesterol to hepatocytes ( 34 ), is enhanced by the ability of albumin to serve as a cholesterol shuttle.…”

Increased plasma cholesterol esterification by LCAT reduces diet-induced atherosclerosis in SR-BI knockout mice

“…RNA was isolated cholesterol by ACAT inhibitors has been shown to accelerate atherosclerosis and increase cardiovascular events in clinical trials ( 12 ). Recently, the enrichment of FC in red blood cell (RBC) plasma membranes has also been implicated in the development of atherosclerosis (13)(14)(15), and RBC cholesterol content has been proposed as a possible cardiovascular biomarker ( 15,16 ). Patients with a wide variety of primary dyslipidemias, such as abetalipoproteinemia, for example, are known to have elevated levels of FC in RBC membranes due to an altered exchange of excess FC on lipoproteins with circulating RBCs ( 2,17 ).…”

Lactobacillus Paracasei NFRI 7415 Reduces Liver Lipid Contents in C57BL/6J Mice Fed a High-fat Diet

“…paracasei NFRI 7415 administration reduced hepatic T-cho concentration. The cholesterol-reducing effect by LAB is known to occur through high cholesterol adsorption on the cell body, and increased bile acid adsorption ability [28,29]. Hepatic cholesterol contents have been shown to be significantly lowered by LABs such as Lactobacillus gasseri and Pediococcus pentosaceus [2,30] In another study on rodents fed a high-fat diet, the hepatic cholesterol content was significantly lowered by P. pentosaceus, and lipid metabolismrelated genes such as cluster of differentiation 36 (CD36) and stearolCoA desaturase 1 (SCD1) showed decreased expression [2] It is necessary to investigate the effect of this strain on mRNA expression in the liver in mice fed HD.…”

“…According to the national health and nutrition survey of 2013 [3], 28.6% of men and 20.3% of women over 20 years old were obese (BMI 25). Obesity is one of the major risk factors of coronary heart disease, arteriosclerosis, fatty liver, diabetes B, hypertension and various other diseases [4].…”