Identification of eleven differentially expressed proteins in the tear film of patients with neovascular Age‐related Macular Degeneration (AMD)

Abstract

AbstractPurposeThe exact mechanisms underlying the age‐related macular degeneration (AMD) are still not totally understood, but processes like inflammation, chronic oxidative stress (OS), and autophagy impairment, are currently believed to have strong influence of the disease development. There are multiple studies concerning changes of the proteome in different tissues in the course of AMD. As they all need invasive procedures to obtain a sample, we sought for a non‐invasive approach. Tear film can be a potential candidte for proteomic information regarding AMD.MethodsTear film was collected on Schirmer strips, 2D‐electrophoresis was performed, and Delta2D software was used for the identification of the differentially expressed proteins from the gels. The spots were excised, and identified by MALDI‐TOF mass spectrometer.Results30 patients were examined, 15 for each group. We have found 469 proteins in the analyzed samples, 11 differentiating proteins fulfilled the criteria of being statistically significant. 3 proteins were up‐regulated (Retinal dehydrogenase 1; ATP‐dependent translocase ABCB1; and alpha‐Enolase), and 8 were down‐regulated (Annexin A1; Annexin A4; Glutathione S‐transferase P; Aldo‐ketoreductase family 1 member A1; Allograft inflammatory factor 1; Cytospin‐A or Elongation factor 2; Short stature homeobox protein 2 and uncharacterized protein C11orf98).ConclusionsTear film can be used as a non‐invasively obtained source of proteomic information about cellular processes ongoing in the course of AMD. The differentially expressed proteins are involved in the choroidal neovascularization, inflammation, oxidative stress and autophagy impairment.