In vitro screening of potential echinochrome delivery systems for the treatment of eye diseases

An important task of topical application of medicines in the treatment of eyes is to achieve a compromise between their effectiveness and safety. The development of new multifunctional local ophthalmic drug delivery systems and in vitro screening of potential medicinal eye products are key areas in solving this problem. In this study, primary in vitro screening of the effect of echinochrome (Ech), the carrageenan complex of echinochrome (CRG/Ech) and its liposomal form (CRG/Ech-Lip) was performed on cultured epithelial cells of the outer shell of the eyeball: conjunctival epithelial cells (Chang Conjunctiva, Clone 1-5c-4) and corneal epithelium human (HCE). The cell viability was assessed by their morphology and metabolic activity using light microscopy and MTT test methods. The direct dependence of the intensity of the cytotoxic effect of Ech on its concentration in the nutrient medium, the form of use, the cellular test system and the incubation time of cells was revealed. Ech in the form of an alcoholic solution in its final concentration of 0.1 mg/ml of the nutrient medium exhibits pronounced cytoxicity against both cellular test systems. The same final concentration of Ech in the nutrient medium, but already as part of the carrageenan complex of echinochrome (CRG/Ech), turned out to be critical only for the viability of corneal epithelial cells, the survival rate of conjunctival cells under these conditions was about 50 %. A high biocompatibility of the liposomal form of the carrageenan complex of echinochrome (CRG/Ech-Lip) with cells of both test systems and a stimulating cytoprotective effect against the cells of the conjunctiva epithelium was revealed.