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Using Caco-2 Cells to Study Lipid Transport by the Intestine
Published on: August 20, 2015
Receptor-Mediated Transcytosis of Leptin through Human Intestinal Cells In Vitro
Philippe G Cammisotto1, Moise Bendayan, Alain Sané
1Departments of Pathology and Cell Biology, University of Montreal, 2900, Bd Edouard-Montpetit, Montreal, Canada H3T 1J4.
International Journal of Cell Biology
|May 11, 2010
Summary
Gastric leptin absorption by intestinal cells involves receptor-mediated transcytosis. This process utilizes clathrin-coated vesicles and the Golgi apparatus for leptin transport into the bloodstream.
Area of Science:
- Gastroenterology
- Cell Biology
- Endocrinology
Background:
- Gastric leptin is absorbed by duodenal enterocytes.
- Leptin is released into the bloodstream from the basolateral side of enterocytes.
- Understanding intestinal leptin transport mechanisms is crucial for metabolic research.
Purpose of the Study:
- To investigate the in vitro mechanisms of gastric leptin transport across intestinal cells.
- To elucidate the role of leptin receptors and cellular pathways in leptin absorption and release.
Main Methods:
- Utilized Caco-2/15 cell models for in vitro studies.
- Investigated leptin uptake and basolateral release kinetics (time, temperature, saturation).
- Employed RNA-mediated silencing, receptor binding assays, endocytosis inhibitors (chlorpromazine), and Golgi markers (brefeldin A, okadaic acid).
- Confocal immunocytochemistry was used to visualize cellular pathways.
Main Results:
- Caco-2/15 cells showed time-, temperature-dependent, and saturable leptin internalization and basolateral release.
- Leptin receptors were identified on the apical brush-border membrane.
- Receptor silencing significantly reduced leptin uptake and release.
- Clathrin-dependent endocytosis inhibition decreased leptin uptake.
- Leptin transit through the Golgi apparatus was confirmed.
Conclusions:
- Intestinal leptin transcytosis is mediated by its receptor.
- Clathrin-coated vesicles are involved in leptin endocytosis.
- Leptin transport involves passage through the Golgi apparatus.
- These findings provide insights into the physiological absorption of gastric leptin.
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