Albumin rescues ocular epithelial cells from cell death in dry eye

Purpose: Because autologous serum is useful for the treatment of severe dry eye, serum components may be a potential candidate for the treatment of dry eye. Serum albumin is abundantly contained in human serum and plays many physiologic roles. We investigated the efficacy of serum albumin in a dry eye animal model. Methods: Sprague-Dawley rats were used to make dry eye model rats according to a previous study. The central region of the corneal epithelium was scraped mechanically, and the rats were placed in a desiccation room (temperature, 23 ± 2°C; humidity, 28 ± 2%; air flow, 2-4 m/s) for 12 hr. During desiccation, one eye of each rat was treated with human serum albumin eye drops, and the other eye was given a drop of phosphate buffered saline (PBS). Human corneal and conjunctival cell lines were used to investigate suppression effect of albumin on apoptosis induced by addition of apoptosis inducers or serum deprivation, respectively. Results: The erosion area was increased by 12 hr of desiccation. Albumin treatment decreased the area of erosion compared with PBS treatment. Apoptosis suppression assay using cell lines revealed that caspase-3 activation induced by serum deprivation and DNA fragmentation induced by addition of apoptosis inducers were dose-dependently suppressed by albumin. Conclusions: Albumin showed a therapeutic effect in dry eye model rats. This efficacy may be related to the suppression of apoptosis by albumin.