Oxidative Stress Biomarkers (oxidative + stress_biomarker)

Distribution by Scientific Domains


Selected Abstracts


Oxidative stress biomarkers in bivalves transplanted to the Guadalquivir estuary after Aznalcóllar spill

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2003
Antonio Romero-Ruiz
Abstract Biological effects of metals were studied in clams (Scrobicularia plana) transplanted to Guadalquivir estuary (Spain) at several times after the spill of toxic metals from Aznalcóllar pyrite mine (southwest Spain) (April 1998) using biochemical biomarkers responsive to reactive oxygen species. Significant As, Cd, Fe, Mn, Ni, and Pb uptake was found in clams living for seven months at the estuary (from July 1999). Increased activity of antioxidant (catalase, glucose-6-phosphate, and 6-phosphogluconate dehydrogenase) and glutathione-related (glutathione reductase and glyoxalase I and II) enzymes was also found after short exposures; the levels of malondialdehyde and metallothionein increased also, particularly with long exposures. Clams living four weeks at the estuary (from March 2000) but not at a reference site also accumulated metals. The higher malondialdehyde and lower reduced-glutathione levels and the more oxidized glutathione status confirmed the oxidative stress of clams living at the estuary, while no marked increase of antioxidant activities was found this time. Lower metal availability along the second transplant could explain the limited responses in this shorter experiment. Although the status of Guadalquivir estuary has recovered since Aznalcóllar spill, continuous monitoring is needed to confirm its progress and to be alert to possible deterioration after heavy rains. [source]


The role of transforming growth factor-,1 and oxidative stress in podoconiosis pathogenesis

BRITISH JOURNAL OF DERMATOLOGY, Issue 5 2010
S. Addisu
Summary Background, Podoconiosis (endemic nonfilarial elephantiasis) occurs in susceptible individuals who go barefoot in regions of irritant volcanic soil. Silicate particles absorbed via the skin are thought to induce an inflammatory process and a consequent endolymphangitis of the lower leg lymphatics. Objectives, To establish which oxidative stress biomarkers play a part in the inflammatory process, and to test whether transforming growth factor (TGF)-,1 also has a pathogenetic role. Patients and methods, We enrolled 50 patients with early clinical stage disease, 43 patients with advanced stage disease and 35 local healthy controls. Oxidative stress biomarkers included serum total peroxides (TP), total antioxidant capacity (TAC), total nitrate plus nitrite (TN), malondialdehyde (MDA) and total superoxide dismutase (SOD) activity. The oxidative stress index (OSI) was also determined. Serum total TGF-,1 was assayed using sandwich enzyme-linked immunosorbent assay. Results, Compared with healthy controls, patients with early stage disease showed significantly higher mean levels of TP (P < 0·001), MDA (P < 0·05) and OSI (P < 0·01); and significantly lower mean concentrations of SOD (P < 0·001) and TGF-,1 (P < 0·001). Mean levels of TGF-,1 were even lower among patients with advanced stage disease (P < 0·001). Mean TAC levels were significantly lower among patients with advanced disease than either other group (P < 0·001). Conclusions, This is the first study, to our knowledge, to attempt to elucidate the molecular pathogenetic events in podoconiosis. We conclude that TGF-,1 may have a pathogenetic role, with oxidative stress playing a minor role in the early stages of disease. [source]


Diabetes, oxidative stress, and antioxidants: A review

JOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 1 2003
A. C. Maritim
Abstract Increasing evidence in both experimental and clinical studies suggests that oxidative stress plays a major role in the pathogenesis of both types of diabetes mellitus. Free radicals are formed disproportionately in diabetes by glucose oxidation, nonenzymatic glycation of proteins, and the subsequent oxidative degradation of glycated proteins. Abnormally high levels of free radicals and the simultaneous decline of antioxidant defense mechanisms can lead to damage of cellular organelles and enzymes, increased lipid peroxidation, and development of insulin resistance. These consequences of oxidative stress can promote the development of complications of diabetes mellitus. Changes in oxidative stress biomarkers, including superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase, glutathione levels, vitamins, lipid peroxidation, nitrite concentration, nonenzymatic glycosylated proteins, and hyperglycemia in diabetes, and their consequences, are discussed in this review. In vivo studies of the effects of various conventional and alternative drugs on these biomarkers are surveyed. There is a need to continue to explore the relationship between free radicals, diabetes, and its complications, and to elucidate the mechanisms by which increased oxidative stress accelerates the development of diabetic complications, in an effort to expand treatment options. © 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:24,38, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10058 [source]


The role of transforming growth factor-,1 and oxidative stress in podoconiosis pathogenesis

BRITISH JOURNAL OF DERMATOLOGY, Issue 5 2010
S. Addisu
Summary Background, Podoconiosis (endemic nonfilarial elephantiasis) occurs in susceptible individuals who go barefoot in regions of irritant volcanic soil. Silicate particles absorbed via the skin are thought to induce an inflammatory process and a consequent endolymphangitis of the lower leg lymphatics. Objectives, To establish which oxidative stress biomarkers play a part in the inflammatory process, and to test whether transforming growth factor (TGF)-,1 also has a pathogenetic role. Patients and methods, We enrolled 50 patients with early clinical stage disease, 43 patients with advanced stage disease and 35 local healthy controls. Oxidative stress biomarkers included serum total peroxides (TP), total antioxidant capacity (TAC), total nitrate plus nitrite (TN), malondialdehyde (MDA) and total superoxide dismutase (SOD) activity. The oxidative stress index (OSI) was also determined. Serum total TGF-,1 was assayed using sandwich enzyme-linked immunosorbent assay. Results, Compared with healthy controls, patients with early stage disease showed significantly higher mean levels of TP (P < 0·001), MDA (P < 0·05) and OSI (P < 0·01); and significantly lower mean concentrations of SOD (P < 0·001) and TGF-,1 (P < 0·001). Mean levels of TGF-,1 were even lower among patients with advanced stage disease (P < 0·001). Mean TAC levels were significantly lower among patients with advanced disease than either other group (P < 0·001). Conclusions, This is the first study, to our knowledge, to attempt to elucidate the molecular pathogenetic events in podoconiosis. We conclude that TGF-,1 may have a pathogenetic role, with oxidative stress playing a minor role in the early stages of disease. [source]


Inflammatory and oxidative stress biomarkers in allergic rhinitis: the effect of smoking

CLINICAL & EXPERIMENTAL ALLERGY, Issue 3 2009
K. Tanou
Summary Background Accumulating evidence confirms the presence of pan-airway inflammation in allergic rhinitis patients. Smoking is known to affect the asthmatic airway inflammation. However, no study has evaluated the impact of smoking on airway inflammation of allergic rhinitis patients. Objective The aim of the present study was to evaluate the impact of smoking on inflammatory and oxidative stress biomarkers in patients with seasonal allergic rhinitis, using non-invasive methods for sample collection. Methods Forty patients with seasonal allergic rhinitis (20 smokers and 20 non-smokers) and 30 healthy subjects (15 smokers and 15 non-smokers) were recruited for the study during pollen season. All subjects were submitted to measurement of the fraction of exhaled NO (FeNO), exhaled breath condensate (EBC) collection, nasal lavage collection, pre- and post- bronchodilation spirometry and metacholine bronchial challenge testing. pH, leukotriene B4 (LTB4) and 8-isoprostane were determined in EBC and nasal lavage samples. Results Patients with allergic rhinitis presented higher LTB4 and 8-isoprostane levels in nasal lavage (P<0.0001 for both comparisons), with no significant differences between smokers and non-smokers. Patients with allergic rhinitis also presented higher LTB4 levels and lower pH in EBC (P<0.001 and P=0.004, respectively), with prominent differences between smokers and non-smokers (P<0.0001 and P=0.003, for LTB4 and pH, respectively). A significant correlation between nasal lavage and EBC LTB4 values was observed (rs=0.313, P=0.048). Conclusions Patients with allergic rhinitis present increased LTB4 and 8-isoprostane in their nasal cavity, however, with no significant differences between smokers and non-smokers. In contrast, smokers with allergic rhinitis present higher LTB4 levels and lower pH in EBC, suggesting that these patients may be more susceptible to the deleterious effects of smoking, compared with non-smokers. [source]