scholarly journals Positive association of pigment epithelium-derived factor with total antioxidant capacity in the vitreous fluid of patients with proliferative diabetic retinopathy

2007 ◽  
Vol 91 (7) ◽  
pp. 885-887 ◽  
Author(s):  
M. Yokoi ◽  
S.-i. Yamagishi ◽  
A. Saito ◽  
Y. Yoshida ◽  
T. Matsui ◽  
...  
Keyword(s):  
Diabetic Retinopathy ◽  
Antioxidant Capacity ◽  
Proliferative Diabetic Retinopathy ◽  
Total Antioxidant Capacity ◽  
Pigment Epithelium ◽  
Positive Association ◽  
Vitreous Fluid ◽  
Pigment Epithelium Derived Factor ◽  
Total Antioxidant

scholarly journals The Association between Diabetic Retinopathy and Levels of Ischemia-Modified Albumin, Total Thiol, Total Antioxidant Capacity, and Total Oxidative Stress in Serum and Aqueous Humor

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Kadir Kirboga ◽  
Ayse V. Ozec ◽  
Mustafa Kosker ◽  
Ayhan Dursun ◽  
Mustafa I. Toker ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Diabetic Retinopathy ◽  
Antioxidant Capacity ◽  
Aqueous Humor ◽  
Total Antioxidant Capacity ◽  
Control Group ◽  
Total Thiol ◽  
Median Serum ◽  
Total Antioxidant ◽  
Total Oxidative Stress

Purpose. To investigate the oxidant and antioxidant status of patients with type 2 diabetes mellitus and nonproliferative diabetic retinopathy (DRP).Methods. Forty-four patients who had cataract surgery were enrolled in the study. We included 22 patients with DRP in one group and 22 patients in the control group. Samples of aqueous humor and serum were taken from all patients. Serum and aqueous ischemia-modified albumin (IMA), total thiol, total antioxidant capacity (TAC), and total oxidative stress (TOS) levels were compared in two groups.Results. Median serum IMA levels were 44.80 absorbance units in the DRP group and 40.15 absorbance units in the control group (P=0.031). Median serum total thiol levels in the DRP group were significantly less than those in the control group (3051.13 and 3910.12, resp.,P=0.004). Mean TOS levels in the serum were 2.93 ± 0.19 in the DRP group and 2.61 ± 0.26 in the control group (P=0.039). The differences in mean total thiol, TAC, and TOS levels in the aqueous humor and mean TAC levels in the serum were not statistically significant.Conclusion. IMA, total thiol, and TOS levels in the serum might be useful markers in monitoring the risk of DRP development.

scholarly journals Total Antioxidant Capacity and Frailty in Older Men

2020 ◽  
Vol 14 (5) ◽  
pp. 155798832094659
Author(s):  
Monica C. Tembo ◽  
Kara L. Holloway-Kew ◽  
Chiara C. Bortolasci ◽  
Sophia X Sui ◽  
Sharon L. Brennan-Olsen ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Sensitivity Analysis ◽  
Antioxidant Capacity ◽  
Total Antioxidant Capacity ◽  
Positive Association ◽  
Older Men ◽  
Clinical Syndrome ◽  
Colorimetric Determination ◽  
Cross Sectional ◽  
Total Antioxidant

Frailty, a clinical syndrome characterized by multisystem dysregulation, has been associated with high levels of oxidative stress. We investigated the association between serum total antioxidant capacity (TAC) and frailty in older men. This cross-sectional study included 581 men (age 60–90 years) enrolled in the Geelong Osteoporosis Study. Frailty comprised at least three of unintentional weight loss, exhaustion, low physical activity, slowness, and weakness. Serum TAC was measured by quantitative colorimetric determination and expressed as uric acid equivalents (mM). Relationships between TAC (in SD units) and frailty were explored using multivariable logistic regression models. Sociodemographic, anthropometric, and lifestyle variables were tested as potential confounders and effect modifiers. A sensitivity analysis excluded participants ( n = 145) in the upper quartile of TAC, who were likely to have hyperuricemia. Fifty (8.6%) men were frail. There was evidence that higher TAC levels were associated with increased likelihood of frailty ( OR 1.34, 95% confidence interval [CI; 0.99, 1.80]), and this was attenuated after adjustment for age and body mass index (BMI; OR 1.26, 95% CI [0.93,1.71]). No effect modifiers or other confounders were identified. The sensitivity analysis revealed a positive association between TAC and frailty, before and after accounting for age and BMI (adjusted OR 1.79, 95% CI [1.01, 3.17] p = .038). These results suggest a positive association between TAC levels and frailty, supporting the hypothesis that this biomarker could be useful in identifying individuals at risk of frailty. We speculate that a milieu of heightened oxidative stress in frailty may elevate the oxidative stress regulatory set point, raising antioxidant activity. This warrants further investigation.

scholarly journals Metabolic Memory Phenomenon and Accumulation of Peroxynitrite in Retinal Capillaries

2007 ◽  
Vol 2007 ◽  
pp. 1-7 ◽  
Author(s):  
Renu A. Kowluru ◽  
Mamta Kanwar ◽  
Alexander Kennedy
Keyword(s):  
Diabetic Retinopathy ◽  
Glycemic Control ◽  
Antioxidant Capacity ◽  
Total Antioxidant Capacity ◽  
Metabolic Memory ◽  
Retinal Microvasculature ◽  
Total Antioxidant ◽  
Acellular Capillaries ◽  
Mnsod Activity ◽  
Retinal Capillaries

Aim. Diabetic retinopathy resists reversal after good glycemic control (GC) is reinitiated, and preexisting damage at the time of intervention is considered as the major factor in determining the outcome of the GC. This study is to investigate the role of peroxynitrite accumulation in the retinal capillaries in the failure of retinopathy to reverse after reestablishment of GC, and to determine the effect of this reversal on the activity of the enzyme responsible for scavenging mitochondrial superoxide, MnSOD.Methods. In streptozotocin-diabetic rats, 6 months of poor glycemic control (PC, glycated hemoglobin,GHb>12.0%) was followed by 6 additional months of GC (GHb about 6%). The trypsin-digested retinal microvessels were prepared for immunostaining of nitrotyrosine (a measure of peroxynitrite) and for counting the number of acellular capillaries (a measure of histopathology). The retina from the other eye was used to quantify nitrotyrosine concentration, MnSOD activity and the total antioxidant capacity.Results. Reversal of hyperglycemia after 6 months of PC had no significant effect on nitrotyrosine concentration in the retina, on the nitrotyrosine-positive retinal capillary cells and on the number of acellular capillaries; the values were similar in PC-GC and PC groups. In the same rats retinal MnSOD activity remained inhibited and the total antioxidant capacity was subnormal 6 months after cessation of PC.Conclusions. Peroxynitrite accumulation in the retinal microvasculature, the site of histopathology, fails to normalize after reversal of hyperglycemia, and superoxide remains inadequately scavenged. This failure of reversal of peroxynitrite accumulation could be, in part, responsible for the resistance of diabetic retinopathy to reverse after termination of PC.

Trans-resveratrol supplement lowers lipid peroxidation responses of exercise in male Wistar rats

2020 ◽  
pp. 1-6 ◽  
Author(s):  
Masoud Nasiri ◽  
Saja Ahmadizad ◽  
Mehdi Hedayati ◽  
Tayebe Zarekar ◽  
Mehdi Seydyousefi ◽  
...  
Keyword(s):  
Lipid Peroxidation ◽  
Antioxidant Capacity ◽  
Total Antioxidant Capacity ◽  
Wistar Rats ◽  
Enzymatic Antioxidants ◽  
Acute Response ◽  
Total Antioxidant ◽  
Male Wistar Rats ◽  
Exercise Induced ◽  
And Control

Abstract. Physical exercise increases free radicals production; antioxidant supplementation may improve the muscle fiber’s ability to scavenge ROS and protect muscles against exercise-induced oxidative damage. This study was designed to examine the effects of all-trans resveratrol supplementation as an antioxidant to mediate anti-oxidation and lipid per-oxidation responses to exercise in male Wistar rats. Sixty-four male Wistar rats were randomly divided into four equal number (n = 16) including training + supplement (TS), training (T), supplement (S) and control (C) group. The rats in TS and S groups received a dose of 10 mg/kg resveratrol per day via gavage. The training groups ran on a rodent treadmill 5 times per week at the speed of 10 m/min for 10 min; the speed gradually increased to 30 m/min for 60 minutes at the end of 12th week. The acute phase of exercise protocol included a speed of 25 m/min set to an inclination of 10° to the exhaustion point. Superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) activity, non-enzymatic antioxidants bilirubin, uric acid, lipid peroxidation levels (MDA) and the total antioxidant capacity (TAC) were measured after the exercise termination. The data were analyzed by using one-way ANOVA. The result showed that endurance training caused a significant increase in MDA level [4.5 ± 0.75 (C group) vs. 5.9 ± 0.41 nmol/l (T group)] whereas it decreased the total antioxidant capacity [8.5 ± 1.35 (C group) vs. 7.1 ± 0.55 mmol/l (T group)] (p = 0.001). In addition, GPx and CAT decreased but not significantly (p > 0.05). The training and t-resveratrol supplementation had no significant effect on the acute response of all variables except MDA [4.3 ± 1.4 (C group) vs. 4.0 ± 0.90 nmol/l (TS group)] (p = 0.001) and TAC [8.5 ± 0.90 (C group) vs. 6.6 ± 0.80 mmol/l (TS group)] (p = 0.004). It was concluded that resveratrol supplementation may prevent exercise-induced oxidative stress by preventing lipid peroxidation.

Sign in / Sign up

Export Citation Format

Share Document