Research On The Effect And Mechanism Of Chitosan To Dry Eyes

Objective TO explore the mechanism of chitosan to dry eyes .Methods Thirty-two healthy New Zealand white rabbits(weight: 2±0.5 Kg) were randomly divided into 4 groups:control group, dry eye model group, chitosan-treated group, and Tears Naturale-treated group.With each group having 16 eyes. Eyes in the control group and dry eye model group were dropped with 2% PBS solution. After 1,2,3,4 weeks of treatment, The rabbits in those groups were examined carefully. Subjects underwent Schirmer test, tear film break-up time (BUT) assay, and fluorescein staining of the ocular surface.After 1,2,3,4 weeks of treatment,the conjunctival samples underwent immunohistochemical staining for Muc-5ac. After one month treatment, conjunctival tissue specimens underwent evaluation for MUC5AC protein expression by means of Western Blot.Results Our results showed that, after 3 weeks treatment, the Schirmer test wetting was lengther and the BUT values were longer in the chitosan-treated group and the Tears Naturale-treated group. After 3 weeks treatment, immunohistochemistry and the OD values from Western Blot revealed the Muc-5ac protein excreted by conjunctival goblet cells was more than before in the chitosan-treated group and the Tears Naturale-treated group. Those changes were all significantly(P<0.05). But the changes in the chitosan-treated group and the Tears Naturale-treated group have no significantly(P>0.05). Conclusion Chitosan can be used to treat dry eyes because it can effectively increase the excreting of Muc-5ac glycoproteins ( an important composing of tear ) by conjunctival goblet cells.