Abstract | PURPOSE: The purpose of this study was to assess the cytotoxic effects of the fluoquinolone ofloxacin and the aminoglycoside netilmicin on stromal human keratocytes in vitro. METHODS: Cultured human keratocytes were exposed to various concentrations of ofloxacin or netilmicin (0.16-5.0 mg/mL). Both cell proliferation (MTT assay) and cell morphology (phase-contrast microscopy) were evaluated after 1, 4, 12, and 24 hours of incubation. Measurement of annexin V binding performed in association with the dye exclusion test using propidium iodide (PI) was also performed by FACS analysis after 4 hours of exposure. RESULTS: Both antimicrobials induced dose- and time-dependent morphologic changes in keratocytes, yet the effects of netilmicin were minimal. After 24 hours of exposure, both drugs induced a dose-dependent inhibition of cell proliferation; however, ofloxacin demonstrated significantly more toxic effects than netilmicin (t test for ED50 values, P < 0.0001). Statistical differences between 2 antibiotics start at concentrations above 1.25 mg/mL (ANOVA with post-hoc test, P < 0.01). Expression of the apoptotic marker annexin V was unaffected by antibiotic exposure, whereas the uptake of the necrotic marker PI was increased by ofloxacin (5 mg/mL) but not by netilmicin ( ofloxacin versus netilmicin, ANOVA, P < 0.05). CONCLUSIONS:
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Authors | Andrea Leonardi, Vincenzo Papa, Iva Fregona, Pietro Russo, Giuseppe De Franchis, Giovanni Milazzo |
Journal | Cornea
(Cornea)
Vol. 25
Issue 1
Pg. 85-90
(Jan 2006)
ISSN: 0277-3740 [Print] United States |
PMID | 16331047
(Publication Type: Comparative Study, Journal Article)
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Chemical References |
- Annexin A5
- Anti-Bacterial Agents
- Tetrazolium Salts
- Thiazoles
- Netilmicin
- Ofloxacin
- thiazolyl blue
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Topics |
- Adult
- Annexin A5
(metabolism)
- Anti-Bacterial Agents
(toxicity)
- Cell Proliferation
(drug effects)
- Cells, Cultured
- Corneal Stroma
(drug effects, metabolism, pathology)
- Dose-Response Relationship, Drug
- Fibroblasts
(drug effects, metabolism, pathology)
- Flow Cytometry
- Humans
- Male
- Microscopy, Phase-Contrast
- Middle Aged
- Netilmicin
(toxicity)
- Ofloxacin
(toxicity)
- Tetrazolium Salts
- Thiazoles
- Time Factors
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