Oxidative and antioxidative stress markers in keratoconus: a systematic review and meta-analysis.
antioxidants
cornea
inflammation
keratoconus
oxidative damage
oxidative stress
reactive oxygen species
stroma
tears
Journal
Acta ophthalmologica
ISSN: 1755-3768
Titre abrégé: Acta Ophthalmol
Pays: England
ID NLM: 101468102
Informations de publication
Date de publication:
Sep 2021
Sep 2021
Historique:
received:
14
09
2020
accepted:
20
11
2020
pubmed:
24
12
2020
medline:
6
1
2022
entrez:
23
12
2020
Statut:
ppublish
Résumé
To conduct a systematic review and meta-analysis on the levels of oxidative stress markers and antioxidants in keratoconus compared to healthy subject. The PubMed, Cochrane Library, Embase, Science Direct and Google Scholar databases were searched on 1st June 2020 for studies reporting oxidative and antioxidative stress markers in keratoconus and healthy controls. Main meta-analysis was stratified by type of biomarkers, type of samples (tears, cornea, aqueous humour and blood) and type of corneal samples (stromal cells, epithelium and endothelium). We included 36 articles, for a total of 1328 keratoconus patients and 1208 healthy controls. There is an overall increase in oxidative stress markers in keratoconus compared with healthy controls (standard mean deviation (SMD) = 0.94, 95% confidence interval (95% CI) 0.55-1.33), with a significant increase in reactive oxygen and nitrogen species (1.09, 0.41-1.78) and malondialdehyde (1.78, 0.83-2.73). There is an overall decrease in antioxidants in keratoconus compared with healthy controls (-0.63, -0.89 to -0.36), with a significant decrease in total antioxidant capacity/status (-1.65, -2.88 to -0.43), aldehyde/NADPH dehydrogenase (-0.77, -1.38 to -0.17), lactoferrin/transferrin/albumin (-1.92, -2.96 to -0.89) and selenium/zinc (-1.42, -2.23 to -0.61). Oxidative stress markers were higher in tears and in cornea of keratoconus than in aqueous humour, and antioxidants were decreased in tears, aqueous humour and blood without difference between sample type. Oxidative stress markers increased in stromal cells and antioxidants decreased in endothelium. Oxidative stress markers and antioxidants were dysregulated in keratoconus, involving an imbalance of redox homeostasis in tears, cornea, aqueous humour and blood.
Substances chimiques
Antioxidants
0
Biomarkers
0
Types de publication
Journal Article
Meta-Analysis
Systematic Review
Langues
eng
Sous-ensembles de citation
IM
Pagination
e777-e794Informations de copyright
© 2020 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.
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