Variability of serum oxidative stress biomarkers relative to biochemical data and clinical parameters of glaucoma patients (original) (raw)

To evaluate the role of oxidative stress in developmentof primary open angle glaucoma

IP innovative publication pvt. ltd, 2020

Introduction and Aims: Primary open angle glaucoma is a chronic optic neuropathy with possible involvement of oxidative stress in its pathogenesis. The present study was conducted to evaluate the role of oxidative stress in terms of lipid peroxide (LPO) and the protective role of antioxidant enzymes catalase (CAT), superoxide-dismutase (SOD) and glutathione peroxidase (GPX) in patients of primary open angle glaucoma. Materials and Methods: A total of 120 patients were enrolled. After taking informed consent, 5 ml of venous blood was taken under aseptic conditions in EDTA tube. These samples were transported from Eye OPD to Laboratory in icebox maintaining temperature for enzymatic activity of enzymes in blood samples. The blood was centrifuged, plasma was separated and was used for estimation of lipid peroxide (LPO). RBC lysates were prepared for estimation of antioxidant enzymes namely; catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx). Results: A total of 120 patients were enrolled. There was no significant difference in LPO levels of POAG patients and controls. No statistically significant difference was observed in the levels of SOD and catalase. There was a significantly raised value of GPx in POAG patients but since SOD activity was normal, we can conclude that the SOD level was sufficient to meet the above exigency.

Evaluation of oxidative stress markers in pathogenesis of primary open-angle glaucoma

Experimental and Molecular Pathology, 2011

Primary open-angle glaucoma (POAG) is the leading cause of blindness in the industrial countries. It is reported that oxidative stress might be an important risk factor in the pathogenesis of POAG. Forty subjects including 20 patients with open-angle glaucoma (9 men and 12 women, mean age 61.8 ± 12.1 yr) and 20 controls without glaucoma symptoms (9 men and 12 women, mean age 58.1 ± 17.7 yr) were enrolled in our study. The main aim of the work was to evaluate oxidative stress markers in the pathogenesis of open-angle glaucoma. In our work the activity of antioxidant enzymes: catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPX) as well as the total antioxidant status (TAS) was estimated. An alkaline comet assay was used to measure DNA damage of strand breaks (SB), oxidized purines as glicosylo-formamidoglicosylase (Fpg) sites, and oxidized pirmidines as endonuclease III (Nth) sites. We measured endogenous as well as exogenous DNA damage after 10 μM hydrogen peroxide treatment (H 2 O 2). We did not observe any statistical changes of DNA strand break lesion in examined POAG patients according to healthy subjects (P N 0.05). However, either endogenous (P b 0.01) or exogenous (P b 0.001) levels of oxidative DNA damage in POAG patients were found to be statistically higher than controls. A significant decrease of antioxidant enzymes: CAT (P b 0.001), SOD (P b 0.05), and GPX (P b 0.001) and a non-statistical decrease of TAS status (P N 0.05) in glaucoma patients according to controls were also indicated. In conclusion our data revealed that oxidative stress had a pathogenic role in primary open-angle glaucoma. Therefore, we suggested that the modulation of a pro-oxidant/antioxidant status might be a relevant target for glaucoma prevention and therapy.

Relationship Between Oxidative Stress and Primary Open-Angle Glaucoma

Journal of Evidence Based Medicine and Healthcare, 2017

BACKGROUND Primary Open-Angle Glaucoma (POAG) is a progressive chronic optic neuropathy, which is not alone related to intraocular pressure. Oxidative stress in conjunction with vascular abnormalities, glial activity, immune system and inflammatory stimulus are presumed to be involved in glaucoma-induced injury. The aim of the study is to evaluate the role of oxidative stress in POAG. MATERIALS AND METHODS It is an observational study conducted on 60 individuals of more than 40 years of age of either sex after ethical clearance and informed consent. 30 patients were confirmed POAG and 30 were age-matched controls of either sex. Patients having angle closure glaucoma, secondary glaucoma or congenital glaucoma, evidence of hepatic and renal diseases, laser and ocular surgeries, any degenerative disorder, age-related macular degenerations or ocular disease, which may increase Intraocular Pressure (IOP) were excluded. 5 mL blood of all patients was taken under aseptic condition in EDTA tube and sample was transferred to biochemistry lab. Parameters assessed were Thiobarbituric Acid-Reactive Substance (TBARS), global antioxidant activity by FRAP method, antioxidant enzymes-superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), ancillary antioxidant enzyme Glutathione Reductase (GR) and Reduced Glutathione (GSH) in hemolysate. RESULTS No significant difference was seen between case and controls with regard to SOD, GSH or CAT levels, but GPx activity was raised in POAG in case as compared to controls. Also, very low Total Antioxidant Activity (TAA) in both case and control are noticed. CONCLUSION The study indicates that oxidative stress was not a risk factor in patient at the point of stage at which they were examined. Thus, it is required that further longitudinal study should be undertaken to examine oxidative stress.

Strategies to Reduce Oxidative Stress in Glaucoma Patients

Current Neuropharmacology, 2017

Background: Primary open-angle glaucoma (POAG) is a multifactorial pathology involving a variety of pathogenic mechanisms, including oxidative/nitrosative stress. This latter is the consequence of the imbalance between excessive formation and insufficient protection against reactive oxygen/nitrogen species. Objective: Our main goal is to gather molecular information to better managing pathologic variants that may determine the individual susceptibility to oxidative/nitrosative stress (OS/NS) and POAG. Method: An extensive search of the scientific literature was conducted using PUBMED, the Web of Science, the Cochrane Library, and other references on the topic of POAG and OS/NS from human and animal model studies published between 2010 and 2017. Finally, 152 works containing relevant information that may help understanding the role of antioxidants, essential fatty acids, natural compounds and other similar strategies for counteracting OS/NS in POAG were considered. Results: A wide variety of studies have proven that antioxidants, among them vitamins B 3 , C and E, Coenzyme Q10 or melatonin, ω-3/ω-6 fatty acids and other natural compounds (such as coffee, green tea, bear bile, gingko biloba, coleus, tropical fruits, etc.,) may help regulating the intraocular pressure as well as protecting the retinal neurons against OS/NS in POAG. Conclusion: Based on the impact of antioxidants and ω-3/ω-6 fatty acids at the molecular level in the glaucomatous anterior and posterior eye segments, further studies are needed by integrating all issues involved in glaucoma pathogenesis, endogenous and exogenous risk factors and their interactions that will allow us to reach newer effective biotherapies for preventing glaucomatous irreversible blindness.

Association of total antioxidants level with glaucoma type and severity

Saudi Medical Journal, 2015

‫العمر‬ ‫من:‬ ‫وكل‬ ‫األكسدة‬ ‫مضادات‬ ‫مجموع‬ ‫مستوى‬ ‫بني‬ ‫معنوى‬ ‫ارتبط‬ ‫للقرص‬ ‫الكأس‬ ‫نسبة‬ ، (R: 0.17، p<0.0001) ‫اإلصابة‬ ‫حدوث‬ ‫عند‬ ‫للزرق‬ ‫املضادة‬ ‫األدوية‬ ‫عدد‬ ‫إلى‬ ‫إضافة‬ ، (R: -0.13، p=0.004) .(R: -0.16, p=0.001) ‫العالج‬ ‫فى‬ ‫املستخدمة‬ ‫أن‬ ‫على‬ ‫واضحة‬ ‫أدلة‬ ‫تقدمي‬ ‫إلى‬ ‫الدراسة‬ ‫هذه‬ ‫نتائج‬ ‫خلصت‬ ‫اخلامتة:‬ ‫الزرق‬ ‫مرضى‬ ‫بني‬ ً ‫منخفضا‬ ‫يكون‬ ‫األكسدة‬ ‫مضادات‬ ‫مجموع‬ ‫مستويات‬ ‫مرضى‬ ‫في‬ ً ‫انخفاضا‬ ‫أقل‬ ‫يكون‬ ‫أنه‬ ‫كما‬ ‫املرض.‬ ‫من‬ ‫املعافني‬ ‫في‬ ‫عنه‬ ‫كما‬ ‫الزاوية.‬ ‫مغلق‬ ‫الزرق‬ ‫في‬ ‫عنه‬ ‫الزاوية‬ ‫ومفتوح‬ ‫التقشيرى‬ ‫الزرق‬ ‫األكسدة‬ ‫مضادات‬ ‫دفاع‬ ‫انخفاض‬ ‫بأن‬ ‫القائلة‬ ‫الفرضية‬ ‫الدراسة‬ ‫دعمت‬ ‫اإلصابة‬ ‫في‬ ً ‫حاسما‬ ً ‫دورا‬ ‫يلعب‬ ‫قد‬ ‫األكسدة‬ ‫معدالت‬ ‫زيادة‬ ‫أو‬ ‫و/‬ ‫املرض.‬ ‫وتطورات‬ ‫بالزرق‬ Objectives: To compare the mean total antioxidant status (TAS) among 3 glaucoma types, namely: pseudoexfoliation glaucoma (PEG), primary open angle glaucoma (POAG), and primary angle closure glaucoma (PACG), and study its potential association with various clinical glaucoma-parameters. Methods: In this case-control study, plasma samples were obtained between September 2013 and October 2014 from 340 glaucoma patients (PEG [n=54]; POAG [n=147]; PACG [n=139]), and 351 controls of matching age, gender, ethnicity, and 5 different systemic comorbidities from King Abdulaziz University Hospital, Riyadh, Saudi Arabia. The TAS in all samples was determined by a colorimetric-based assay. Results: The mean±standard deviation of TAS was significantly lower among cases: 0.77±0.32 than controls: 1.1±0.22, p<0.0001. Moreover, the TAS levels were significantly different across the 3 types of glaucoma: 0.86±0.24 in PEG, 0.47±0.32 in POAG, and 0.98±0.41 in PACG (all p<0.0001). In addition, there was a significant correlation between TAS and age at onset (Pearson correlation coefficient [R] 0.17, p<0.0001), cup/disc ratio (R: -0.13, p=0.004), and number of antiglaucoma medications (R: -0.16, p=0.001).

Oxidative Stress–Related Molecular Biomarker Candidates for Glaucoma

Investigative Opthalmology & Visual Science, 2017

PURPOSE. Glaucoma-related molecular biomarkers can improve clinical testing to diagnose the disease early, predict its prognosis, and monitor treatment responses. Based on the evidence of increased oxidative stress in glaucomatous tissues, this study analyzed oxidative stressrelated biomarker candidates in blood and aqueous humor samples with or without glaucoma. METHODS. The blood and aqueous humor samples collected from carefully selected groups of 96 patients with glaucoma and 64 healthy subjects without glaucoma were included in the study. The samples were analyzed for protein carbonyls and advanced glycation end products (AGEs) through ELISA-based quantification assays. To allow proper comparisons, the Goldmann-Witmer coefficient that reflects the ratio of aqueous humor to blood values corrected to total protein concentration in individual samples was calculated. RESULTS. Blood and aqueous humor levels of protein carbonyls and AGEs were found significantly higher in glaucomatous samples compared with age-matched nonglaucomatous controls (P < 0.001). The glaucoma-related increase in protein carbonyls and AGEs was more prominent in aqueous humor samples than blood samples (2.6-fold versus 1.9-fold for protein carbonyls, and 3.1-fold versus 1.9-fold for AGEs; P < 0.001). Comparison of the Goldmann-Witmer coefficients indicated greater values for protein carbonyls (1.37 6 0.3 vs. 3.07 6 0.8) and AGEs (1.2 6 0.3 vs. 3.2 6 1.1) in the glaucoma group (P < 0.001). CONCLUSIONS. Findings of this study encourage further validation studies of oxidative stressrelated biomarkers in glaucoma. Analysis of protein carbonyls and AGEs in longitudinal studies of larger and heterogeneous patient cohorts should better assess the value of these promising candidates as molecular biomarkers of glaucoma for clinical predictions.

Role of oxidative stress enzymes in open-angle glaucoma

Eye, 2005

Purpose To investigate the role of oxidative stress and lipid peroxidation in the pathogenesis of primary open-angle glaucoma (POAG). Materials and methods The activities of myeloperoxidase (MPO), catalase (CAT), and the levels of plasma malondialdehyde (MDA) were measured in 40 (15 men and 25 women) patients with POAG and 60 (30 men and 30 women) healthy controls.

Time Course Changes of Oxidative Stress Markers in a Rat Experimental Glaucoma Model

Investigative Ophthalmology & Visual Science, 2010

To evaluate the relationship between oxidative stress markers and increased intraocular pressure in experimental glaucoma. METHODS. In vivo chemiluminescence (CL), total antioxidant capacity (TRAP), nitrite concentration (NC), and lipid peroxidation markers (TBARS) were evaluated. Wistar rats (n ϭ 18 for each time point) underwent operation, and two episcleral veins were cauterized. RESULTS. Decreases of 22%, 35%, and 27% at 7, 15, and 30 days and an increase of 22% at 60 days in CL were observed in glaucomatous eyes. In optic nerve, TBARS values were 6.9 Ϯ 0.5 nmol/mg protein ), 9.4 Ϯ 0.4 nmol/mg protein (15 days), 18.0 Ϯ 1.2 nmol/mg protein (30 days), and 43.1 Ϯ 5.3 nmol/mg protein (60 days) (control, 6.2 Ϯ 0.4 nmol/mg protein; P Ͻ 0.001). NC was 37.0 Ϯ 1.8 M (7 days), 31.4 Ϯ 1.2 M (15 days), 39.6 Ϯ 1.3 M (30 days), and 40.0 Ϯ 1.3 M (60 days) (control, 21.1 Ϯ 1.7 M; P Ͻ 0.001). In glaucomatous vitreous humor, TRAP decreased by 42% at 15 days and 78% at 60 days (control, 414 Ϯ 29 M; P Ͻ 0.001). In glaucomatous aqueous humor, TRAP values were 75 Ϯ 7 M (7 days), 54 Ϯ 4 M (15 days), 25 Ϯ 4 M (30 days), and 50 Ϯ 3 M (60 days) (control, 90 Ϯ 10 M; P Ͻ 0.001). CONCLUSIONS. Reactive species were increased in glaucoma, as evidenced by the increases in CL, TBARS, and NC. The decrease in the antioxidant levels may be a consequence of an increase in oxidative processes. (Invest Ophthalmol Vis Sci.

Oxidative stress markers in aqueous humor of glaucoma patients

American Journal of Ophthalmology, 2004

PURPOSE: Oxidative stress and antioxidant status in eye tissues may be associated with glaucomatous damage. The aim of this study was to establish the antioxidant status of aqueous humor of patients with primary openangle glaucoma. For this purpose the authors measured the total reactive antioxidant potential (TRAP) and the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase, and glutathione peroxidase. • DESIGN: Case control study.