Biomaterial Database

Reactive oxygen species, oxidative stress, glaucoma and hyperbaric oxygen therapy. 2018

Charles McMonnies

School of Optometry and Vision Science, University of New South Wales, Australia. Electronic address: c.mcmonnies@unsw.edu.au.

This review examines the role of oxidative stress in damage to cells of the trabecular meshwork and associated impaired aqueous drainage as well as damage to retinal ganglion cells and associated visual field losses. Consideration is given to the interaction between vascular and mechanical explanations for pathological changes in glaucoma. For example, elevated intraocular pressure (IOP) forces may contribute to ischaemia but there is increasing evidence that altered blood flow in a wider sense is also involved. Both vascular and mechanical theories are involved through fluctuations in intraocular pressure and dysregulation of blood flow. Retinal function is very sensitive to changes in haemoglobin oxygen concentration and the associated variations in the production of reactive oxygen species. Reperfusion injury and production of reactive oxygen species occurs when IOP is elevated or blood pressure is low and beyond the capacity for blood flow autoregulation to maintain appropriate oxygen concentration. Activities such as those associated with postural changes, muscular effort, eye wiping and rubbing which cause IOP fluctuation, may have significant vascular, mechanical, reperfusion and oxidative stress consequences. Hyperbaric oxygen therapy exposes the eye to increased oxygen concentration and the risk of oxidative damage in susceptible individuals. However, oxygen concentration in aqueous humour, and the risk of damage to trabecular meshwork cells may be greater if hyperbaric oxygen is delivered by a hood which exposes the anterior ocular surface to higher than normal oxygen levels. Oronasal mask delivery of hyperbaric oxygen therapy appears to be indicated in these cases.

UI	MeSH Term	Description	Entries
D007429	Intraocular Pressure	The pressure of the fluids in the eye.	Ocular Tension,Intraocular Pressures,Ocular Tensions,Pressure, Intraocular,Pressures, Intraocular,Tension, Ocular,Tensions, Ocular
D005901	Glaucoma	An ocular disease, occurring in many forms, having as its primary characteristics an unstable or a sustained increase in the intraocular pressure which the eye cannot withstand without damage to its structure or impairment of its function. The consequences of the increased pressure may be manifested in a variety of symptoms, depending upon type and severity, such as excavation of the optic disk, hardness of the eyeball, corneal anesthesia, reduced visual acuity, seeing of colored halos around lights, disturbed dark adaptation, visual field defects, and headaches. (Dictionary of Visual Science, 4th ed)	Glaucomas
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006931	Hyperbaric Oxygenation	The therapeutic intermittent administration of oxygen in a chamber at greater than sea-level atmospheric pressures (three atmospheres). It is considered effective treatment for air and gas embolisms, smoke inhalation, acute carbon monoxide poisoning, caisson disease, clostridial gangrene, etc. (From Segen, Dictionary of Modern Medicine, 1992). The list of treatment modalities includes stroke.	Oxygenation, Hyperbaric,Hyperbaric Oxygen Therapy,Hyperbaric Oxygen Therapies,Hyperbaric Oxygenations,Oxygen Therapies, Hyperbaric,Oxygen Therapy, Hyperbaric,Oxygenations, Hyperbaric,Therapies, Hyperbaric Oxygen,Therapy, Hyperbaric Oxygen
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012165	Retinal Ganglion Cells	Neurons of the innermost layer of the retina, the internal plexiform layer. They are of variable sizes and shapes, and their axons project via the OPTIC NERVE to the brain. A small subset of these cells act as photoreceptors with projections to the SUPRACHIASMATIC NUCLEUS, the center for regulating CIRCADIAN RHYTHM.	Cell, Retinal Ganglion,Cells, Retinal Ganglion,Ganglion Cell, Retinal,Ganglion Cells, Retinal,Retinal Ganglion Cell
D014129	Trabecular Meshwork	A porelike structure surrounding the entire circumference of the anterior chamber through which aqueous humor circulates to the SCHLEMM'S CANAL.	Meshwork, Trabecular,Meshworks, Trabecular,Trabecular Meshworks
D017382	Reactive Oxygen Species	Molecules or ions formed by the incomplete one-electron reduction of oxygen. These reactive oxygen intermediates include SINGLET OXYGEN; SUPEROXIDES; PEROXIDES; HYDROXYL RADICAL; and HYPOCHLOROUS ACID. They contribute to the microbicidal activity of PHAGOCYTES, regulation of SIGNAL TRANSDUCTION and GENE EXPRESSION, and the oxidative damage to NUCLEIC ACIDS; PROTEINS; and LIPIDS.	Active Oxygen Species,Oxygen Radical,Oxygen Radicals,Pro-Oxidant,Reactive Oxygen Intermediates,Active Oxygen,Oxygen Species, Reactive,Pro-Oxidants,Oxygen, Active,Pro Oxidant,Pro Oxidants,Radical, Oxygen
D018384	Oxidative Stress	A disturbance in the prooxidant-antioxidant balance in favor of the former, leading to potential damage. Indicators of oxidative stress include damaged DNA bases, protein oxidation products, and lipid peroxidation products (Sies, Oxidative Stress, 1991, pxv-xvi).	Anti-oxidative Stress,Antioxidative Stress,DNA Oxidative Damage,Nitro-Oxidative Stress,Oxidative Cleavage,Oxidative DNA Damage,Oxidative Damage,Oxidative Injury,Oxidative Nitrative Stress,Oxidative Stress Injury,Oxidative and Nitrosative Stress,Stress, Oxidative,Anti oxidative Stress,Anti-oxidative Stresses,Antioxidative Stresses,Cleavage, Oxidative,DNA Damage, Oxidative,DNA Oxidative Damages,Damage, DNA Oxidative,Damage, Oxidative,Damage, Oxidative DNA,Injury, Oxidative,Injury, Oxidative Stress,Nitrative Stress, Oxidative,Nitro Oxidative Stress,Nitro-Oxidative Stresses,Oxidative Cleavages,Oxidative DNA Damages,Oxidative Damage, DNA,Oxidative Damages,Oxidative Injuries,Oxidative Nitrative Stresses,Oxidative Stress Injuries,Oxidative Stresses,Stress Injury, Oxidative,Stress, Anti-oxidative,Stress, Antioxidative,Stress, Nitro-Oxidative,Stress, Oxidative Nitrative,Stresses, Nitro-Oxidative