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The influence of a lipophilic derivative of Edaravone (C18Edv) on a POPC liposomal bilayer has been investigated by a combined computational-experimental approach. The order and hydration degree of three different systems composed by 10%, 20% and 40% in w/w percentage of C18Edv respect to POPC were investigated through Molecular Dynamics (MD) simulations and fluorescence spectroscopy experiments. Dynamic Light Scattering measurements showed how the presence of different amounts of C18EdV determines differences on liposome size and stability. The survey revealed that the content of lipophilic antioxidant tunes liposome rigidity and influences cellular uptake and antioxidant activity which are maximized for formulation containing 20% of C18Edv.

Amino acids are the basic constituents of living organisms, and have both a structural and an active dynamic role in tissue and cell physiology. Human tears contain 23 amino acids, the relative proportion of which may change with the different physiological states of the eye surface. In this review, we present a collection of data from the published literature that indicate an active role of amino acids in the maintenance of eye surface homeostasis. Moreover, another series of published clinical data indicate that supplementation of amino acids, either as food supplements or as a topical treatment in enriched eye drops, is beneficial to the eye surface, and may improve its healing in cases of eye surface disease due to different causes.

Aim of the present study is to extend our previous observations on a model of primary epithelial cell culture obtained from bovine conjunctiva, and analyse the maintenance of the conjunctival phenotype, relative to cytokeratin (CK) expression, through extended periods of cultivation under different conditions. Conjunctival epithelial cells were grown in transwell filters, and cultured either under liquid covered (LC), or air-interface (AI) conditions. The physiological state of the cells was monitored daily by measurement of the trans-epithelial electrical resistance (TEER). Analysis of cytokeratin expression was then carried out at different time points (up until 14 days), and compared to the original profile of the conjunctival tissue in order to assess deviations from the primitive phenotype. Immunodetection studies, carried out by both western immunoblot and immunofluorescence analyses, revealed constant expression of the pan-epithelial marker AE3 (recognizing basic type cytokeratins), confirming the epithelial nature of the culture. Other cytokeratins characteristic of non-keratinized stratified epithelia (CK4 and CK13) were absent in corneal tissue, while in conjunctival epithelial cells were more expressed under AI than under LC culture conditions. Expression of CK12, a specific marker of corneal tissue, revealed by the antibody AE5, was never observed in conjunctival epithelial cells. These results indicate that the conjunctival phenotype is conserved during extended periods of culturing, making this system a reliable substitute of conjunctival tissue for pharmaceutical analyses.

The objective of this paper is to assess the gelatinase production by some ocular pathogenic bacterial strains, and evaluate the ability of (-)epigallocatechin-3-gallate (EGCg) to inhibit this gelatinase activity and thus limit bacterial invasion. The effect of EGCg on bacterial gelatinase activity was tested by classic zymography methods, while its effect on bacterial invasion was evaluated through the ability of growing bacteria to liquefy and thus penetrate a semisolid gelatine substrate. It was found that EGCg inhibits bacterial gelatinases with an IC(50) of about 0.2 mM, and limits invasion of gelatinase-positive bacteria at concentrations above 2 mM. These results show for the first time that EGCg, as well as having direct antibacterial activity, can also inhibit bacterial gelatinases, thus limiting their invasion on gelatine. Possible use of EGCg is thus suggested as an adjuvant in antibacterial chemotherapy.

The high-molecular-weight fucosyl glycopeptides of differentiated F9 cells have been analyzed. We found that these high-molecular-weight surface structures contain two components with different molecular weights, the largest of which, peak I, has never before been reported. The material eluting in this peak seems to contain only acidic species. Removal of sialic acid from both the peak I and the peak II species does not eliminate the differences in molecular weight, indicating that the two species have more profound structural differences that can be accounted for by sialic acid. Since peak I glycopeptides were found both in differentiated F9 cells and in two parietal endoderm cell lines, we suggest that its presence is related to parietal endoderm differentiation.