19
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Serum Antioxidative Enzymes Levels and Oxidative Stress Products in Age-Related Cataract Patients

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Purpose. To investigate the activity of antioxidative enzymes and the products of oxidative stress in patients with age-related cataracts and compare the findings with those in healthy control subjects. Method. Sixty patients with age-related cataract and sixty healthy controls of matched age and gender were included in this study. Serum samples were obtained to detect the antioxidative enzymes of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px), and oxidation degradation products of malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), conjugated diene (CD), advanced oxidation protein products (AOPP), protein carbonyl (PC), and 8-hydroxydeoxyguanosine (8-OHdG). Results. Serum SOD, GSH-Px, and CAT activities in cataract group were significantly decreased as compared to the control subjects ( P < 0.05). The levels of MDA, 4-HNE, and CD in cataract patients were significantly higher than those in the control subjects ( P < 0.05, P < 0.01). Cataract patients had higher levels of 8-OHdG, AOPP, and PC with respect to the comparative group of normal subjects ( P < 0.01). And there was no statistical significance in concentration of antioxidative enzymes and oxidative stress products in patients with different subtype cataract. Conclusions. Oxidative stress is an important risk factor in the development of age-related cataract, and augmentation of the antioxidant defence systems may be of benefit to prevent or delay cataractogenesis.

          Related collections

          Most cited references 45

          • Record: found
          • Abstract: found
          • Article: not found

          A simple method for clinical assay of superoxide dismutase.

          This assay for superoxide dismutase (SOD, EC 1.15.1.1) activity involves inhibition of nitroblue tetrazolium reduction, with xanthine-xanthine oxidase used as a superoxide generator. By using a reaction terminator, we can determine 40 samples within 55 min. One unit of activity of pure bovine liver Cu,ZnSOD and chicken liver MnSOD was expressed by 30 ng and 500 ng of protein, respectively. The mean concentrations of Cu,ZnSOD as measured by this method in blood from normal adults were 242 (SEM 4) mg/L in erythrocytes, 548 (SEM 20) micrograms/L in serum, and 173 (SEM 11) micrograms/L in plasma. The Cu,ZnSOD concentrations in serum and plasma of patients with cancer of the large intestine tended to be less and greater than these values, respectively, but not statistically significantly so.
            Bookmark
            • Record: found
            • Abstract: not found
            • Article: not found

            Oxidative damage to proteins: spectrophotometric method for carbonyl assay.

              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Age-related nuclear cataract-oxidation is the key.

              Age is by far the biggest risk factor for cataract, and it is sometimes assumed that cataract is simply an amplification of this aging process. This appears not to be the case, since the lens changes associated with aging and cataract are distinct. Oxidation is the hallmark of age-related nuclear (ARN) cataract. Loss of protein sulfhydryl groups, and the oxidation of methionine residues, are progressive and increase as the cataract worsens until >90% of cysteine and half the methionine residues are oxidised in the most advanced form. By contrast, there may be no significant oxidation of proteins in the centre of the lens with advancing age, even past age 80. The key factor in preventing oxidation seems to be the concentration of nuclear glutathione (GSH). Provided that nuclear GSH levels can be maintained above 2 mm, it appears that significant protein oxidation and posttranslational modification by reactive small molecules, such as ascorbate or UV filter degradation products, is not observed. Adequate coupling of the metabolically-active cortex, the source of antioxidants such as GSH, to the quiescent nucleus, is crucial especially since it would appear that the cortex remains viable in old lenses, and even possibly in ARN cataract lenses. Therefore it is vital to understand the reason for the onset of the lens barrier. This barrier, which becomes apparent in middle age, acts to impede the flow of small molecules between the cortex and the nucleus. The barrier, rather than nuclear compaction (which is not observed in human lenses), may contribute to the lowered concentration of GSH in the lens nucleus after middle age. By extending the residence time within the lens centre, the barrier also facilitates the decomposition of intrinsically unstable metabolites and may exacerbate the formation of H(2)O(2) in the nucleus. This hypothesis, which is based on the generation of reactive oxygen species and reactive molecules within the nucleus itself, shifts the focus away from theories for cataract that postulated a primary role for oxidants generated outside of the lens. Unfortunately, due to marked variability in the lenses of different species, there appears at present to be no ideal animal model system for studying human ARN cataract.
                Bookmark

                Author and article information

                Journal
                Oxid Med Cell Longev
                Oxid Med Cell Longev
                OXIMED
                Oxidative Medicine and Cellular Longevity
                Hindawi Publishing Corporation
                1942-0900
                1942-0994
                2013
                28 May 2013
                : 2013
                Affiliations
                1Clinical Labororatory, The First Affiliated Hospital of Harbin Medical University, Harbin 150081, China
                2Department of Ophtalmology, The Second Affiliated Hospital of Harbin Medical University, Harbin 150081, China
                3Public Health School, Mudanjiang Medical College, Mudanjiang 157011, China
                4Department of Ophtalmology, Eye Hospital of Heilongjiang Province and the First Affiliated Hospital of Harbin Medical University, Harbin 150081, China
                5Department of Nutrition and Food Hygiene, Public Health School of Harbin Medical University, Harbin 150081, China
                Author notes

                Academic Editor: Peter Shaw

                Article
                10.1155/2013/587826
                3679765
                23781296
                Copyright © 2013 Dong Chang et al.

                This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

                Categories
                Clinical Study

                Molecular medicine

                Comments

                Comment on this article