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Porphyromonas gingivalis as a Model Organism for Assessing Interaction of Anaerobic Bacteria with Host Cells
Published on: December 17, 2015
Clarithromycin transport by gingival fibroblasts and epithelial cells
1College of Dentistry, The Ohio State University Health Sciences Center, Columbus, OH 43218-2357, USA.
Journal of Dental Research
|July 25, 2008
Summary
Gingival fibroblasts and oral epithelial cells actively transport clarithromycin, a macrolide antibiotic. This active uptake mechanism may improve clarithromycin
Area of Science:
- Pharmacology
- Cell Biology
- Microbiology
Background:
- Macrolide antibiotics are known to enter cells, but the precise mechanisms remain largely uncharacterized.
- Understanding cellular uptake is crucial for optimizing antibiotic efficacy, particularly in challenging environments like the oral cavity.
Purpose of the Study:
- To elucidate the cellular uptake mechanisms of clarithromycin in human gingival fibroblasts and oral epithelial cells (SCC-25).
- To investigate whether clarithromycin transport is an active or passive process and to characterize its kinetic properties.
Main Methods:
- Human gingival fibroblasts and SCC-25 cells were incubated with radiolabeled [(3)H]-clarithromycin.
- Cell-associated radioactivity was measured over time to quantify clarithromycin accumulation.
- Transport kinetics were analyzed by varying clarithromycin concentrations and temperatures, assessing Michaelis-Menten parameters.
Main Results:
- Both cell types demonstrated rapid intracellular accumulation of clarithromycin, reaching steady-state concentrations within 15 minutes.
- Clarithromycin uptake exhibited Michaelis-Menten kinetics and was temperature-dependent, indicating an active transport process.
- Specific kinetic parameters (Michaelis constant and maximum transport velocity) were determined for both fibroblasts and SCC-25 cells.
Conclusions:
- Gingival fibroblasts and oral epithelial cells utilize a concentrative active transport system for clarithromycin uptake.
- This active transport mechanism can significantly increase intracellular clarithromycin concentrations, potentially enhancing its effectiveness against invasive periodontal pathogens.
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