Isolation of Plasma Lipoproteins as a Source of Extracellular RNA
Plasma lipoproteins are essential vehicles of lipid distribution for cellular energy and structural requirements as well as for excretion of lipid excess. Imbalances in lipoprotein metabolism are known to contribute to metabolic diseases ranging from vascular inflammation and atherosclerosis to obesity and diabetes. The lipid and protein cargo carried by lipoprotein subclasses have long been the focus of studies exploring the contribution of plasma lipoproteins in health and in metabolic disorders. More recent studies have revealed the presence of noncoding RNA as a new form of cargo carried by plasma lipoproteins. Lipoprotein-associated microRNAs have been identified to distribute differentially among plasma lipoprotein subclasses and contribute to cellular signaling. These findings highlight plasma lipoprotein-associated RNA as a potential source of biological signaling and warrant a renewed interest in the study of plasma lipoprotein biology. This chapter describes principles and methods based on density ultracentrifugation and size exclusion chromatography for the isolation of plasma lipoproteins as a source of extracellular RNA.
KeywordsLipoprotein Sequential density ultracentrifugation FPLC chromatography HDL VLDL LDL Extracellular RNA
This work was supported by grants from the National Institutes of Health; 5U19CA179512 and 1U01HL126493 Extracellular RNA Communication Consortium Common Fund, and HL133575 to (R.L.R.) which was administered by the Northern California Institute for Research and Education. The work was performed at the Veterans Affairs Medical Center, San Francisco, CA. We thank Phat Duong and Allen Chung for excellent technical assistance with SDS-PAGE.
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