Search

Ocular surface diseases are becoming more prevalent worldwide. Reasons for this include the ongoing population ageing and increasing use of digital displays, although ophthalmologists have a wide selection of tools, which can be implemented in the evaluation of the ocular surface health, methods, which enable the in‐depth study of biological functions are gaining more interest. These new approaches are needed, since the individual responses to ocular surface diseases and treatments can vary from person to person, and the correlations between clinical signs and symptoms are often low. Modern mass spectrometry (MS) methods can produce information on hundreds of tear proteins, which in turn can provide valuable information on the biological effects occurring on the ocular surface. In this review article, we will provide an overview of the different aspects, which are part of a successful tear proteomics study design and equip readers with a better understanding of the methods most suited for their MS‐based tear proteomics study in the field of ophthalmology and ocular surface. [ABSTRACT FROM AUTHOR]

Purpose: To conduct a systematic review and meta‐analysis on the levels of oxidative stress markers and antioxidants in dry eye disease (DED) compared with healthy subject. Method: The PubMed, Cochrane Library, Embase, Science Direct and Google Scholar databases were searched on 10 January 2021 for studies reporting oxidative and antioxidative stress markers in DED and healthy controls. Main meta‐analysis was stratified by type of biomarkers, type of samples (tears, conjunctival cells or biopsies), Sjögren's syndrome (SS) (patients with or without SS) and by geographical zones (Asia or Europe). Results: We included nine articles, for a total of 333 patients (628 eye samples) with DED and 165 healthy controls (451 eye samples). There is an overall increase in oxidative stress markers in DED compared with healthy controls (standard mean deviation = 2.39, 95% confidence interval 1.85–2.94), with a significant increase in lipid peroxide (1.90, 0.69–3.11), myeloperoxidase (2.17, 1.06–3.28), nitric oxide synthase 3 (2.52, 0.95–4.08), xanthine oxidase/oxidoreductase (2.41, 1.40–5.43), 4‐hydroxy‐2‐nonenal (4HNE) (4.75, 1.67–7.84), malondialdehyde (3.00, 2.55–3.45) and reactive oxygen species (1.31, 0.94–1.68). Oxidative stress markers were higher in tears, conjunctival cells and conjunctival biopsies of DED than controls. Even if small number of studies were included for antioxidants, catalase seemed to be decreased in DED compared with healthy controls (−2.17, −3.00 to −1.34), with an increase of antioxidants in tears of DED patients without SS (1.13, 0.76–1.49). Conclusion: Oxidative stress markers, and probably antioxidants, were dysregulated in DED, establishing a local oxidative environment in tears, conjunctival cells and tissues. [ABSTRACT FROM AUTHOR]