Assessment of Eyebright (Euphrasia Officinalis L.) Extract Activity in Relation to Human Corneal Cells Using In Vitro Tests

Abstract

Background:Euphrasia officinalisL. is anherbtraditionally usedin folk medicine, mainly in the treatment of eye disorders. Aims:Thepresent study analyzed theactivity of three extracts of E. officinalis L.(ethanol, ethyl acetate andheptane) oncultured human corneal epithelial cells (10.014 pRSV-T). Study Design:In vitro study.Methods:Toxicity, freeradical scavenging activity andtheimmu-nomodulatory effects oftheextracts were tested using thethiazo-lylbluetetrazolium bromide (MTT) orNeutral Red,2,2-Diphenyl-1-picrylhydrazyl (DPPH) andELISA tests, respectively. Moreover, nitric oxide levels andcytoskeleton architecture wereanalyzed after corneal cell incubation with the plant extracts.Results:Weshow thatthebiological effect depended onboththe concentration andtheextraction solvent used. Heptane extracts,distinct from those inethanol andethyl acetate, were toxic to 10.014 pRSV-T cells atlowconcentrations (25?g/mL) anddid notdemonstrate freeradical scavenging effects. Alltested extractsdecreased pro-inflammatory cytokine expression (IL-1?, IL-6and TNF-?) andalsoanti-inflammatory IL-10 expression byhumancorneal cellswhen theextracts were added to thecellculture me-dium for 24 h.Conclusion:In conclusion, weshow thatthepromising effects of the application of E. officinalis L. preparations as a supplementary thera-pyforeyedisorders areassociated withtheethanol andethyl acetate extracts, not the heptane extract.