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Free Radicals and Antioxidants
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
Glutathione peroxidases (GSHPx) are found both in the cytoplasm and extracellularly in almost every human tissue (22). The biochemical activity of glutathione peroxidase is to reduce free hydrogen peroxide (H2O2) to water (H2O) and to reduce lipid hydroperoxides to their corresponding alcohols. They protect the cell against oxidative injury caused by H2O2 and prevent the formation of hydroxyl radical (•OH) from H2O2 (21). GSHPx convert the oxidant H2O2 into water with the aid of its coenzyme glutathione (GSH). The last one is oxidized into glutathione disulfide (GS-SG) (21, 22, 87).
Inherited Defects in Immune Defenses Leading to Pulmonary Disease
Published in Stephen D. Litwin, Genetic Determinants of Pulmonary Disease, 2020
Girls have also been described who had the same clinical entity but did not inherit it as an X-linked trait. These cases may be deficient in glutathione peroxidase [124]. Males suffering from the X-linked form of CGD have normal glutathione peroxidase levels.
Herbs with Antidepressant Effects
Published in Scott Mendelson, Herbal Treatment of Major Depression, 2019
The herb also produces anti-inflammatory and antioxidative effects both peripherally and centrally. In vitro, extracts of Melissa officinalis had neuroprotective effects against Aβ-induced cytotoxicity and oxidative stress in cultured PC12 cells, a neuron-like cell line derived from a pheochromocytoma of the rat adrenal medulla. Production of reactive oxygen species was reduced, as were levels of the lipid peroxidation biomarkers, malondialdehyde, and thiobarbituric acid reactive substances. Glutathione peroxidase activity was increased.4 Extracts of Melissa officinalis also exert anti‑oxidative and anti-inflammatory neuroprotective effects in vivo. In rats subjected to transient hippocampal ischemia, oil of Melissa officinalis inhibited generation of malondialdehyde and reduced concentrations of thiobarbituric acid reactive substances in the hippocampus. It also significantly increased the antioxidant enzyme caspase and suppressed expression of the hypoxiainducible factor 1-alpha gene, which is induced under conditions of hypoxia.5
Benzo-a-pyrene-induced reproductive toxicity was abated in rats co-treated with taurine
Published in Toxin Reviews, 2022
Solomon E. Owumi, Opeoluwa Popoola, Moses T. Otunla, Uche A. Okuu, Eseroghene S. Najophe
The testes (right testis) and epididymis were homogenized in 50 mM Tris–HCl buffer (pH 7.4), and the homogenates were centrifuged at 4 °C for 15 min at 3000 ×g. The supernatant was used for biochemical analysis of oxidative stress status. Lipid peroxidation (LPO) was determined by methods described by Buege and Aust (1978). Catalase (CAT) and superoxide dismutase (SOD) activities were analyzed according to the methods of Clairborne (1995) and Misra and Fridovich (1972), respectively. Glutathione peroxidase (GPx) activity and Glutathione (GSH) level were analyzed as described by the reported methods of Rotruck et al. (1973) and Jollow et al. (1974), respectively. Also, glutathione‐S‐transferase (GST) enzyme activity was assayed for by Habig et al. (1974) methods. Xanthine oxidase (XO) activity was estimated at 290 nm according to the previously reported method of Bergmeyer et al. (1974). Briefly, xanthine solution (1.00 ml), sample (0.10 ml), and phosphate buffer (1.90 ml) were pipetted and quickly mixed in cuvettes by simple inversion. Spectrophotometric readings (absorbance at 290 nm) were obtained every minute by monitoring the absorbance for 3 min. A blank reference reading was also obtained by replacing the samples (0.10 ml) with distilled deionized water in the reaction mixture above. Xanthine oxidase activity was calculated as follows:
Evaluation of oxidative stress biomarkers and liver and renal functional parameters in patients during treatment a mental health unit to treat alcohol dependence
Published in Drug and Chemical Toxicology, 2022
Samuel Selbach Dries, Bruna Scherer Seibert, Marcos Frank Bastiani, Rafael Linden, Magda Susana Perassolo
The activity of glutathione peroxidase was measured by the method described by Pleban et al. (1982). The working solution was prepared with: 50 mmol/l Tris buffer at pH 7.6, containing 1 mmol Na2EDTA per liter, 2 mmol reduced glutathione, 0.2 mmol NADPH, 4 mmol sodium azide and 1000 U of glutathione reductase. Incubate the mixture for 5 min at 37 °C. To determine enzymatic activity in plasma, 50 μL of undiluted plasma was added to 950 μL of the working solution. The activity of GSH-Px was expressed in plasma U/L. After a period of 30 s, the decrease in absorbance is linear with time. For the start of the reaction 10 μL of H2O2 8.8 mmol/L was added, followed by the decrease of the NADPH at 340 nm absorbance for 3 min. The blank tube was prepared, and instead of plasma, water was added.
The Relationship between Ocular Vascular Changes and the Levels of Malondialdehyde and Vascular Endothelial Growth Factor in Patients with Inflammatory Bowel Disease
Published in Ocular Immunology and Inflammation, 2021
Nilay Sengul Samanci, Sule Poturoglu, Cesur Samanci, Fethi Emre Ustabasioglu, Macit Koldas, Ali Erkan Duman, Aslı Ciftcibası Ormeci
Tüzün et al23 measured glutathione peroxidase and MDA levels (markers of oxidative stress) in IBD patients. Plasma glutathione peroxidase levels were higher in CD and UC patients than controls. No significant difference was found for MDA levels between the patients and controls. We found that the MDA level was highest in CD patients, followed by UC patients and controls. It may because in this study the disease duration of CD is longer than that of UC patients. Thus, reactive oxygen species play roles in IBD. In CD patients, the OARI correlated negatively with VEGF level. If VEGF was increased in CD patients, OARI would be reduced, but OARI was higher than control. Also the CRAPSV correlated positively with MDA level. This shows that when oxidative stress increases, systolic pressure in the central retinal artery increases. MDA values higher than controls on CD, but CRAPSV values lower than controls. This suggests that other variables, as well as VEGF and MDA, may have influenced OARI and CRAPSV values and also other values. When we evaluated the interobserver agreement in RI measurements, we found that two observers achieved highly compatible results with each other (Table 3). This was very important in terms of demonstrating the reproducibility of this method in the evaluation of RI.