Dataset Information

Interleukin 10 promotes macrophage uptake of HDL and LDL by stimulating fluid-phase endocytosis.

ABSTRACT:

Objective

Highly elevated plasma levels of interleukin-10 (IL-10) are causally associated with "Disappearing HDL Syndrome" and low plasma LDL-cholesterol, but the underlying mechanism is poorly understood. Fluid-phase endocytosis, a process highly dependent on actin dynamics, enables cells to internalize relatively high amounts of extracellular fluids and solutes. We sought to investigate whether IL-10 induces lipoprotein uptake by fluid-phase endocytosis in macrophages.

Methods and results

Macrophages (RAW264.7, Kupffer and human) were incubated with vehicle (PBS) or IL-10 (20?ng/ml) for 7?days. Uptake of HDL, LDL, and/or fluid-phase endocytosis probes (albumin-Alexa680®, 70?kDa FITC-Dextran and Lucifer Yellow, LY) was evaluated by FACS. Intracellular cofilin and phosphorylated cofilin (p-cofilin) levels were determined by immunoblotting. Macrophage uptake of lipoproteins and probes was non-saturable and increased after IL-10 incubation (p?ConclusionsInterleukin-10 induces the uptake of HDL and LDL by fluid-phase endocytosis by increasing actin-filament rearrangement in macrophages, thus providing a plausible mechanism contributing to "Disappearing HDL Syndrome".

SUBMITTER: Lucero D

PROVIDER: S-EPMC6993958 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Publications

Interleukin 10 promotes macrophage uptake of HDL and LDL by stimulating fluid-phase endocytosis.

Lucero Diego D Islam Promotto P Freeman Lita A LA Jin Xueting X Pryor Milton M Tang Jingrong J Kruth Howard S HS Remaley Alan T AT

Biochimica et biophysica acta. Molecular and cell biology of lipids 20191030 2

<h4>Objective</h4>Highly elevated plasma levels of interleukin-10 (IL-10) are causally associated with "Disappearing HDL Syndrome" and low plasma LDL-cholesterol, but the underlying mechanism is poorly understood. Fluid-phase endocytosis, a process highly dependent on actin dynamics, enables cells to internalize relatively high amounts of extracellular fluids and solutes. We sought to investigate whether IL-10 induces lipoprotein uptake by fluid-phase endocytosis in macrophages.<h4>Methods and r ...[more]

PMID: 31676439

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Dataset Information

Interleukin 10 promotes macrophage uptake of HDL and LDL by stimulating fluid-phase endocytosis.

Objective

Methods and results

Publications

Interleukin 10 promotes macrophage uptake of HDL and LDL by stimulating fluid-phase endocytosis.

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