Superoxide Anion Generation in the Liver During the Early Stage of Endotoxemia in Rats

Bautista, Abraham P.; Mészáros, Károly; Bojta, J; Spitzer, John J.

doi:10.1002/jlb.48.2.123

Cited by 182 publications

(89 citation statements)

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“…Free radicals, generated mainly by Kupffer cells, are thought to cause tissue injury by initiating lipid peroxidation and inducing irreversible modifications of cell membrane structure and function. 67,68 In an animal model of endotoxemia, preadministration of TJ-9 was found to significantly increase the activity of superoxide dismutase and of glutathione peroxide, which are part of a chemical and enzymatic antioxidant defense system, in the liver, suggesting that TJ-9 acts by protecting against plasma membrane damage by free radicals. 56 In hepatic fibrosis, TJ-9 may exert its suppressive effects, at least in part, through its antioxidant activity, by acting as a radical scavenger, and/or by stimulating interferon-␥.…”

Section: Discussionmentioning

confidence: 99%

Effects of Sho–Saiko–To, A Japanese Herbal Medicine, on Hepatic Fibrosis in Rats

Shimizu¹,

Ma²,

Mizobuchi³

et al. 1999

Hepatology

226

189

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It has been shown that lipid peroxidation is associated with hepatic fibrosis and stellate cell activation. Shosaiko-to (TJ-9) is an herbal medicine, which is commonly used to treat chronic hepatitis in Japan, although the mechanism by which TJ-9 protects against hepatic fibrosis is not known. As a result, we assayed the preventive and therapeutic effects of TJ-9 on experimental hepatic fibrosis, induced in rats by dimethylnitrosamine (DMN) or pig serum (PS), and on rat stellate cells and hepatocytes in primary culture, and assessed the antioxidative activities and the active components of TJ-9. Male Wistar rats were given a single intraperitoneal injection of 40 mg/kg DMN or 0.5 mL PS twice weekly for 10 weeks. In each model, rats were fed a basal diet throughout, or the same diet, which also contained 1.5% TJ-9, for 2 weeks before treatment or for the last 2 weeks of treatment. TJ-9 suppressed the induction of hepatic fibrosis, increased hepatic retinoids, and reduced the hepatic levels of collagen and malondialdehyde (MDA), a production of lipid peroxidation. Immunohistochemical examination showed that TJ-9 reduced the deposition of type I collagen and the number of ␣-smooth muscle actin (␣-SMA) positive-stellate cells in the liver and inhibited, not only lipid peroxidation in cultured rat hepatocytes that were undergoing oxidative stress, but also the production of type I collagen, ␣-SMA expression, cell proliferation, and oxidative burst in cultured rat stellate cells. In addition, TJ-9 inhibited Fe 2؉ /adenosine 5Ј-diphosphate-induced lipid peroxidation in rat liver mitochondria in a dose-dependent manner and showed radical scavenging activity. Among the active components of TJ-9, baicalin and baicalein were found to be mainly responsible for the antioxidative activity. These findings suggest that Sho-saiko-to (TJ-9) functions as a potent antifibrosuppressant by inhibition of lipid peroxidation in hepatocytes and stellate cells in vivo. (HEPATOLOGY 1999;29:149-160)

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Section: Discussionmentioning

confidence: 99%

Effects of Sho–Saiko–To, A Japanese Herbal Medicine, on Hepatic Fibrosis in Rats

Shimizu¹,

Ma²,

Mizobuchi³

et al. 1999

Hepatology

226

189

View full text Add to dashboard Cite

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“…In LPS-exposed Kupffer cells, NADPH oxidase becomes activated, resulting in elevated production and release of superoxide anions and hydrogen peroxide [15,16,18]. The increased capacity of HMS after LPS or tumor necrosis factor ␣ administration shows good correlation with elevated superoxide anion production in activated Kupffer cells [16].…”

Section: Endotoxemia and The Intracellular Oxidant Balancementioning

confidence: 91%

“…The extracellular component of oxidative stress is rendered on parenchymal cells from sinusoidal sources. Activated Kuppfer cells produce and release large quantities of superoxide anion, hydrogen peroxide, nitric oxide, and their derivatives, which target the surrounding tissue [2,[15][16][17][18][19][20]. Acute nonspecific immune stimuli also initiate prompt margination, adherence, and subsequent infiltration of blood neutrophils into the liver [4,21].…”

Section: Oxidative Stress In the Hepatic Sinusoidmentioning

confidence: 99%

Endotoxemia, pentose cycle, and the oxidant/antioxidant balance in the hepatic sinusoid

Spolarics

1998

Journal of Leukocyte Biology

115

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During the innate immune response, excessive release of reactive oxygen species (ROS) from sequestered phagocytes and activated resident macrophages represents the predominant component of oxidative stress in the liver and other tissues. The consequence of oxidative stress is determined by the status and adaptive changes of antioxidant pathways. In this review, we present evidence that the synchronized response of hepatic sinusoidal endothelial cells, the primary sites of phagocyte attachment, plays an important role in defense against phagocyte-derived ROS. An essential component of the metabolic adaptation of hepatic sinusoidal cells to lipopolysaccharide (LPS)-induced oxidative stress is the stimulated expression of glucose-6-phosphate dehydrogenase (G6PD), the key enzyme of the pentose cycle (hexose monophosphate shunt, HMS). All major ROS-metabolic enzymes, i.e., glutathione peroxidase, glutathione reductase, catalase, superoxide dismutases, NADPH oxidase, and nitric oxide synthase, directly or indirectly depend on NADPH, which is produced in the HMS in these cells. The functional significance of up-regulated HMS within a particular cell type depends on the accompanying adaptive changes in ROS-metabolizing enzymes. In LPS-activated Kupffer cells, the elevated expression of glucose transporter GLUT1 and G6PD mainly serves primed production of superoxide anion, hydrogen peroxide, and nitric oxide. In sinusoidal endothelial cells, the LPS-induced response pattern of glucose-and ROS-metabolizing enzymes results in elevated ROS detoxifying capacity. The described studies also suggest the existence of an intercellular oxidant balance between prooxidant Kupffer cells and antioxidant endothelial cells in the hepatic micro-environment. Maintenance of the intercellular oxidant/antioxidant balance between phagocytes and endothelial cells may represent an important mechanism protecting the hepatic parenchyma against exogenous oxidative stress during the inflammatory response. J. Leukoc. Biol. 63: 534-541; 1998.

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“…Antioxidants act as free radical scavengers and can prevent the damage caused by oxidative reactions, including cancer, Alzheimer's and Parkinson's diseases [2,3,4,5,6]. Hence, the evaluation of the antioxidative activity of medical, cosmetic and food samples provides useful clinical information [7].…”

Section: Introductionmentioning

confidence: 99%

New Approach for Measuring Antioxidant Activity Via a Graphite Sensor

El-Kosasy¹,

Hussien²,

Abdel‐Rahman³

2014

Port. Electrochim. Acta

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An ion selective membrane sensor from dioctyl phthalate as a plasticizer in a polymeric matrix of polyvinyl chloride (PVC) and β-cyclodextrin as an ionophore was constructed and evaluated according to IUPAC recommendations. Linear Nernstian response of DPPH• within the concentration ranges of 10 −6 to 10 −2 mol L −1 was obtained with average recovery 99.87±0.617. Nernstian slope of 58.5 mV/decade with excellent selectivity over the pH range of 3-8 was observed. The suggested method was standardized using butylated hydroxyl anisole (BHA). The 50% radical scavenging activity (IC 50 ) determined by the proposed sensor correlated well with that of the common spectrophotometric method based on scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH • ). An algorithm implemented in Microsoft Visual Basic ® 6.0 was used for calculating (IC 50 ) values which are 7.38 µg/mL ± 0.35, 89.98 µg/ mL ± 0.45 and 1.45 mg/ mL ± 1.50 for BHA, Paracetamol and Dipyridamole, respectively. The proposed sensor represents a simple and reproducible tool for measuring DPPH • scavenging activity of Paracetamol and Dipyridamole in bulk powder, pharmaceutical formulations and simulated intestinal fluid (SIF) without sophisticated separation techniques.

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Superoxide Anion Generation in the Liver During the Early Stage of Endotoxemia in Rats

Cited by 182 publications

References 0 publications

Effects of Sho–Saiko–To, A Japanese Herbal Medicine, on Hepatic Fibrosis in Rats

Effects of Sho–Saiko–To, A Japanese Herbal Medicine, on Hepatic Fibrosis in Rats

Endotoxemia, pentose cycle, and the oxidant/antioxidant balance in the hepatic sinusoid

New Approach for Measuring Antioxidant Activity Via a Graphite Sensor

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