Balkan Med J. 2014 Mar;31(1):29-36. doi: 10.5152/balkanmedj.2014.8377. Epub 2014 Mar 1.

Assessment of eyebright (euphrasia officinalis L.) extract activity in relation to human corneal cells using in vitro tests.

Paduch R1, Woźniak A2, Niedziela P3, Rejdak R2.

• 1Department of Virology and Immunology, Maria Curie-Sklodowska University Faculty of Biology and Biotechnology, Lublin, Poland.
• 2Department of General Ophthalmology, Medical University of Lublin, Lublin, Poland.
• 3Department of Surgery, District Railway Hospital, Lublin, Poland.

Abstract

BACKGROUND:

Euphrasia officinalis L. is an herb traditionally used in folk medicine, mainly in the treatment of eye disorders.

AIMS:

The present study analyzed the activity of three extracts of E. officinalis L. (ethanol, ethyl acetate and heptane) on cultured human corneal epithelial cells (10.014 pRSV-T).

STUDY DESIGN:

In vitro study.

METHODS:

Toxicity, free radical scavenging activity and the immunomodulatory effects of the extracts were tested using the thiazolyl blue tetrazolium bromide (MTT) or Neutral Red, 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and ELISA tests, respectively. Moreover, nitric oxide levels and cytoskeleton architecture were analyzed after corneal cell incubation with the plant extracts.

RESULTS:

We show that the biological effect depended on both the concentration and the extraction solvent used. Heptane extracts, distinct from those in ethanol and ethyl acetate, were toxic to 10.014 pRSV-T cells at low concentrations (25 μg/mL) and did not demonstrate free radical scavenging effects. All tested extracts decreased pro-inflammatory cytokine expression (IL-1β, IL-6 and TNF-α) and also anti-inflammatory IL-10 expression by human corneal cells when the extracts were added to the cell culture medium for 24 h.

CONCLUSION:

In conclusion, we show that the promising effects of the application of E. officinalis L. preparations as a supplementary therapy for eye disorders are associated with the ethanol and ethyl acetate extracts, not the heptane extract.

KEYWORDS:

Cytotoxicity; Euphrasia officinalis extracts; human corneal cells; immunomodulation; reactive oxygen species scavenging effect

PMID:  25207164