Cholesterol Transport Between Cells and Body Fluids: Role of Plasma Lipoproteins and the Plasma Cholesterol Esterification System

1982 ◽  
Vol 66 (2) ◽  
pp. 363-373 ◽  
Author(s):  
Christopher J. Fielding ◽  
Phoebe E. Fielding
Keyword(s):  
Plasma Cholesterol ◽  
Body Fluids ◽  
Plasma Lipoproteins ◽  
Cholesterol Esterification ◽  
Cholesterol Transport

scholarly journals Cholesterol transport between red blood cells and lipoproteins contributes to cholesterol metabolism in blood

2020 ◽  
Vol 61 (12) ◽  
pp. 1577-1588
Author(s):  
Ryunosuke Ohkawa ◽  
Hann Low ◽  
Nigora Mukhamedova ◽  
Ying Fu ◽  
Shao-Jui Lai ◽  
...  
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Cholesterol Efflux ◽  
Cholesterol Metabolism ◽  
Plasma Cholesterol ◽  
Translocator Protein ◽  
Plasma Lipoproteins ◽  
Cholesterol Transport ◽  
Autologous Plasma

Lipoproteins play a key role in transport of cholesterol to and from tissues. Recent studies have also demonstrated that red blood cells (RBCs), which carry large quantities of free cholesterol in their membrane, play an important role in reverse cholesterol transport. However, the exact role of RBCs in systemic cholesterol metabolism is poorly understood. RBCs were incubated with autologous plasma or isolated lipoproteins resulting in a significant net amount of cholesterol moved from RBCs to HDL, while cholesterol from LDL moved in the opposite direction. Furthermore, the bi-directional cholesterol transport between RBCs and plasma lipoproteins was saturable and temperature-, energy-, and time-dependent, consistent with an active process. We did not find LDLR, ABCG1, or scavenger receptor class B type 1 in RBCs but found a substantial amount of ABCA1 mRNA and protein. However, specific cholesterol efflux from RBCs to isolated apoA-I was negligible, and ABCA1 silencing with siRNA or inhibition with vanadate and Probucol did not inhibit the efflux to apoA-I, HDL, or plasma. Cholesterol efflux from and cholesterol uptake by RBCs from Abca1+/+ and Abca1−/− mice were similar, arguing against the role of ABCA1 in cholesterol flux between RBCs and lipoproteins. Bioinformatics analysis identified ABCA7, ABCG5, lipoprotein lipase, and mitochondrial translocator protein as possible candidates that may mediate the cholesterol flux. Together, these results suggest that RBCs actively participate in cholesterol transport in the blood, but the role of cholesterol transporters in RBCs remains uncertain.

scholarly journals A Critical Evaluation of the Role of Soy Protein and Isoflavone Supplementation in the Control of Plasma Cholesterol Concentrations

2006 ◽  
Vol 91 (3) ◽  
pp. 772-780 ◽  
Author(s):  
Antonella Dewell ◽  
Piper L. W. Hollenbeck ◽  
Clarie B. Hollenbeck
Keyword(s):  
Soy Protein ◽  
Plasma Cholesterol ◽  
Evidence Synthesis ◽  
Critical Evaluation ◽  
Clinical Importance ◽  
Clinical Analysis ◽  
Plasma Lipoproteins ◽  
Extensive Literature ◽  
Sources Of Information

Abstract Context: The purpose of this review was to critically evaluate current research on the effect of soy protein and isoflavone supplements on plasma lipoproteins and place the potential role of soy in the prevention of coronary artery disease (CAD) into a clinical perspective. Evidence Acquisition: An extensive literature search was performed using a variety of medical and scientific databases including Medline, PubMed, Science Direct, Ovid, NIST, and Infotrac to identify relevant articles. Journal articles were cross-referenced for additional sources of information. Articles were evaluated based on level of experimental control as well as statistical, quantitative, and clinical analysis. Evidence Synthesis: Soy and soy isoflavones have been the object of extensive research investigating their potential hypocholesterolemic effects and possible role in the prevention of CAD. It has been suggested that soy, especially the isoflavones contained in soy, improves lipoprotein levels, thus reducing the risk for CAD. This belief, however, is not uniformly accepted. Moreover, the experimental evidence in support of this notion is not as overwhelming as generally perceived, and the current available data reveal that the discrepancies observed are primarily statistical in nature rather than reflecting actual quantitative differences in the hypocholesterolemic effects detected. Conclusions: A critical analysis of the investigations to date indicates the data are not quantitatively impressive and raises substantial questions about the clinical importance of the hypocholesterolemic effects observed.

scholarly journals Immunoregulatory plasma lipoproteins. Role of apoprotein E and apoprotein B.

1980 ◽  
Vol 255 (24) ◽  
pp. 11775-11781
Author(s):  
D.Y. Hui ◽  
J.A. Harmony ◽  
T.L. Innerarity ◽  
R.W. Mahley
Keyword(s):  
Plasma Lipoproteins ◽  
Apoprotein B ◽  
Apoprotein E

scholarly journals Localisation and regulation of cholesterol transporters in the human hair follicle: mapping changes across the hair cycle

2021 ◽  
Author(s):  
Megan A. Palmer ◽  
Eleanor Smart ◽  
Iain S. Haslam
Keyword(s):  
Hair Follicle ◽  
Human Hair ◽  
Vital Role ◽  
Transport Proteins ◽  
Hair Follicles ◽  
Regulatory Control ◽  
Cholesterol Transport ◽  
Hair Cycle ◽  
Human Hair Follicle

AbstractCholesterol has long been suspected of influencing hair biology, with dysregulated homeostasis implicated in several disorders of hair growth and cycling. Cholesterol transport proteins play a vital role in the control of cellular cholesterol levels and compartmentalisation. This research aimed to determine the cellular localisation, transport capability and regulatory control of cholesterol transport proteins across the hair cycle. Immunofluorescence microscopy in human hair follicle sections revealed differential expression of ATP-binding cassette (ABC) transporters across the hair cycle. Cholesterol transporter expression (ABCA1, ABCG1, ABCA5 and SCARB1) reduced as hair follicles transitioned from growth to regression. Staining for free cholesterol (filipin) revealed prominent cholesterol striations within the basement membrane of the hair bulb. Liver X receptor agonism demonstrated active regulation of ABCA1 and ABCG1, but not ABCA5 or SCARB1 in human hair follicles and primary keratinocytes. These results demonstrate the capacity of human hair follicles for cholesterol transport and trafficking. Future studies examining the role of cholesterol transport across the hair cycle may shed light on the role of lipid homeostasis in human hair disorders.

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