EVALUATION OF STILLAVITR ARTIFICIAL TEARS POTENTIAL IN REDUCING THE TOXIC EFFECT OF BENZALKONIUM CHLORIDE-CONTAINING HYPOTENSIVE INSTILLATIONS ON PRIMARY CELL CULTURE OF THE CORNEAL LIMBUS (EXPERIMENTAL STUDY)

PURPOSE: To evaluate the cytotoxicity of hypotensive instillation containing benzalkonium chloride and the protective effect of StillavitR artificial tears on the corneal limbus primary cell culture.

METHODS: Test samples: 1) latanoprost 0.005%, containing benzalkonium chloride (BC) 0.02% as a preservative agent 2) StillavitR, containing sodium hyaluronate 0,16%, chondroitin sulfate sodium of 0.05%, D-panthenol 1% and sodium tetraborate 0,05% acting as preservative. Primary cell culture of the corneal limbus was used for the assessment. At the first stage of the research we estimated the effect of a 100% concentration of latanoprost+BC and Stillavit on the cell culture. At the second stage we analyzed the influence of agents’serial dilution on cytotoxicity indicators. The aim of the third stage was the assessment of cell viability level after their exposure to diluted substances in three various combinations: single latanoprost + BC (30 min exposure); simultaneous and consecutive adding of Stillavit and latanoprost + BC to the culture with a 30 min interval. To evaluate the cell culture viability we carried out MTS test using CellTiter 96R AQueous One Solution Reagent («Promega»). Obtained results underwent additional cytological examination.

RESULTS: Cell viability level after the exposure to a 100% concentration of latanoprost+BC amounted to 13.95Ѓ}4.014%. In cases of exposing the culture to a combination of latanoprost + BC and Stillavit, viability level reached 22.03Ѓ}3.152%. The second stage of the research revealed that the cell culture has a survival rate of 60-80% if the drug (latanoprost + BC) in the sample is diluted 32-fold, and in relation to drug volume amounts to 6.25%. Consequently, in the third stage of the research we evaluated cell viability level exposing them to a 6.25% dilution of the drug. Cell survival rate after single latanoprost + BC exposure equaled 68.49Ѓ}20.61%. Both simultaneous and consecutive adding of Stillavit (30 min prior to the drug) increased cell survival rate: 94.95Ѓ}of 12.52 and 103.8Ѓ}12.45% respectively. The observed difference was statistically significant in both cases (95% reliability level).

CONCLUSION: In vitro studies results have shown the protective effect of Stillavit artificial tears on the cell culture in combination with both 100% and 6.25% latanoprost + BC, confirmed by a cytological examination.

cytotoxicity, benzalkonium chloride, cell culture corneal limbus, glaucoma, glaucoma therapy, Stillavit

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