Topical application of nucleotides increase lysozyme levels in tears

Abstract

Assumpta Peral1, Patricia Loma2, Benjamin Yerxa3, Jesús Pintor21Departamento de Óptica II (Optometría y Visión), Escuela Universitaria de Óptica, Universidad Complutense de Madrid, Madrid, Spain; 2Departamento de Bioquímica y Biología Molecular IV, Escuela Universitaria de Óptica, Universidad Complutense de Madrid, Madrid, Spain; 3Inspire Pharmaceuticals, Inc. Durham, North Carolina, USAAbstract: The present work studies the effects of topical application of nucleotides on rabbit tear lysozyme levels. Lysozyme values were determined by the diffusion in Agar method described by van Bijsterveld in 1974, and the protein amount was obtained by measuring the inhibitory halos around a Whatman nº1 paper disc of 5 mm in diameter. The tested nucleotides were UTP, Ap4A and Up4U. These compounds were topically instilled in a single-dose in one eye (with the contralateral eye as a control) and the lysozyme halos were measured along 5 hours. The obtained results showed an increase in the lysozyme concentrations of 67%, 93%, and 119% for UTP, Ap4A, and Up4U, respectively, over the basal levels of lysozyme. For this reason, we suggest these molecules as a potential treatment for the reinforcement of the tear film barrier against ocular infection.Keywords: lysozyme, nucleotides, tear film, ocular infection, ocular protection, ocular surface