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04:50
Imaging FITC-dextran as a Reporter for Regulated Exocytosis
Published on: June 20, 2018
Cyclodextrin induces calcium-dependent lysosomal exocytosis.
Fannie W Chen1, Chunlei Li, Yiannis A Ioannou
1Department of Genetics and Genomic Sciences, The Mount Sinai School of Medicine, New York, New York, USA.
Plos One
|December 3, 2010
Summary
2-hydroxypropyl-β-cyclodextrin (HPB-CD) treatment stimulates lysosomal exocytosis, clearing cholesterol from Niemann-Pick Type C cells. This mechanism offers potential therapeutic benefits for cholesterol storage disorders.
Area of Science:
- Cell Biology
- Biochemistry
- Genetics
Background:
- Cyclodextrins (CDs) are known to modulate cellular cholesterol levels.
- Their precise cellular mechanisms, especially in cholesterol storage diseases, remain unclear.
- Recent studies highlight CDs' potential in Niemann-Pick Type C (NPC) disease.
Purpose of the Study:
- To investigate if 2-hydroxypropyl-β-cyclodextrin (HPB-CD) stimulates lysosomal exocytosis.
- To determine if calcium enhances this HPB-CD-induced exocytosis.
- To propose lysosomal exocytosis as the mechanism for ameliorating NPC cellular phenotypes.
Main Methods:
- Cellular treatment with HPB-CD.
- Calcium concentration manipulation.
- Analysis of lysosomal exocytosis markers.
- Assessment of cholesterol levels in NPC cells.
Main Results:
- HPB-CD treatment was found to stimulate lysosomal exocytosis.
- This effect was enhanced in the presence of increased calcium levels.
- HPB-CD treatment successfully reduced the cholesterol storage phenotype in NPC cells.
Conclusions:
- HPB-CD treatment promotes lysosomal exocytosis in a calcium-dependent manner.
- This process underlies HPB-CD's ability to correct cholesterol accumulation in NPC cells.
- Findings impact HPB-CD applications in research and potential therapies for NPC disease.
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