Xue CHEN, Xu WANG, Lu GUO, et al. Macropinocytosis mediates accumulation of lipid droplets in vascular smooth muscle cells in vitro[J]. Journal of Third Military Medical University, 2018, 40(2): 103-108.
DOI:
Xue CHEN, Xu WANG, Lu GUO, et al. Macropinocytosis mediates accumulation of lipid droplets in vascular smooth muscle cells in vitro[J]. Journal of Third Military Medical University, 2018, 40(2): 103-108. DOI: 10.16016/j.1000-5404.201709029.
Macropinocytosis mediates accumulation of lipid droplets in vascular smooth muscle cells in vitro
To investigate whether macropinocytosis mediates the accumulation of lipid droplets in vascular smooth muscle cells (VSMCs).
Methods
2
Primary VSMCs were cultured with tissue explant method and identified by immunofluorescence staining. VSMCs-derived foam cells were induced by stimulation of the VSMCs with native low-density lipoprotein (nLDL) at 50
200
or 800 μg/mL and lipopolysaccharide (LPS) at 200 ng/mL. The changes in the uptake of Lucifer Yellow (LY) and DiI-nLDL by the VSMCs were assessed with flow cytometry.
Results
2
LPS promoted lipid droplet accumulation in nLDL-stimulated VSMCs in a concentration-dependent manner. The primary cultured VSMCs showed significantly increased LY uptake by 75% (
P
<
0.01) and DiI-nLDL uptake by 76% (
P
<
0.01) in response to stimulation with 200 ng/mL LPS for 6 h. The uptake of DiI-nLDL was significantly lowered by 29% (
P
<
0.01) and lipid droplet accumulation was significantly decreased in the cells after treatment with LY294002 for inhibiting macropinocytosis.
Conclusion
2
LPS induces the uptake of nLDL by VSMCs via the macropinocytosis pathway to promote the formation of VSMCs-derived foam cells.
关键词
Keywords
references
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