Beta-2-Agonists Have Antioxidant Function in vitro. 1. Inhibition of Superoxide Anion, Hydrogen Peroxide, Hypochlorous Acid and Hydroxyl Radical

Respiration ◽  
1997 ◽  
Vol 64 (1) ◽  
pp. 16-22 ◽  
Author(s):  
Adrian Gillissen ◽  
Malgorzata Jaworska ◽  
Birgit Schärling ◽  
Dominique van Zwoll ◽  
Gerhard Schultze-Werninghaus
1988 ◽  
Vol 65 (5) ◽  
pp. 2349-2353 ◽  
Author(s):  
L. S. Terada ◽  
C. J. Beehler ◽  
A. Banerjee ◽  
J. M. Brown ◽  
M. A. Grosso ◽  
...  

Xanthine oxidase (XO) and xanthine dehydrogenase (XD) activities decreased in lungs isolated from rats and cultured lung endothelial cells that had been exposed to hyperoxia. Purified XO activity also decreased after addition of a variety of chemically generated O2 metabolite species (superoxide anion, hydrogen peroxide, hydroxyl radical, or hypochlorous acid), hypoxanthine, or stimulated neutrophils in vitro. XO inactivation by chemically, self-, or neutrophil-generated O2 metabolites was decreased by simultaneous addition of various O2 metabolite scavengers but not their inactive analogues. Since XO appears to contribute to a variety of biological processes and diseases, hyperoxia- or O2 metabolite-mediated decreases in XO activity may be an important cellular control mechanism.


2010 ◽  
Vol 5 (2) ◽  
pp. 224-230 ◽  
Author(s):  
Boobalan Raja ◽  
Kodukkur Pugalendi

AbstractIn this study, an aqueous extract of leaves from Melothria maderaspatana was tested for in vitro antioxidant activity. Free radical scavenging assays, such as hydroxyl radical, hydrogen peroxide, superoxide anion radical and 2,2-diphenyl-1-picryl hydrazyl (DPPH), 2,2’-azinobis-(3-ethyl-enzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, and reducing power assay, were studied. The extract effectively scavenged hydroxyl radical, hydrogen peroxide and superoxide anion radicals. It also scavenged DPPH and ABTS radicals. Furthermore, it was found to have reducing power. All concentrations of leaf extract exhibited free radical scavenging and antioxidant power, and the preventive effects were in a dose-dependent manner. The antioxidant activities of the above were compared to standard antioxidants such as butylated hydroxytoluene (BHT), ascorbic acid, and α-tocopherol. The results obtained in the present study indicate that the M. maderaspatana extract could be considered a potential source of natural antioxidant.


2009 ◽  
Vol 4 (12) ◽  
pp. 1934578X0900401
Author(s):  
Rokia Sanogo ◽  
Antonio Vassallo ◽  
Nicola Malafronte ◽  
Salvatore Imparato ◽  
Alessandra Russo ◽  
...  

One new flavonoid glycoside, 3-O-kaempferol 4-O-(galloyl)-β-D-glucoside, one new bergenin derivative, 11-0-caffeoylbergenin, along with other known flavonoids and phenolic derivatives, were isolated from the leaves of Securinega virosa. Their structures were established on the basis of detailed spectral analysis. In vitro biological analysis of the isolated compounds showed that they were able to quench DPPH radicals and had a direct scavenging activity on superoxide anion. Kaempferol 3-O-(4-galloyl)-β-D-glucopyranoside (1), 11-0-caffeoylbergenin (2), and glucogallin (6) exhibited the highest antioxidant capacity, being also able to modulate hydroxyl radical formation more efficiently than the other compounds, acting as direct hydroxyl radical scavengers and chelating iron.


Nanomaterials ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 1040 ◽  
Author(s):  
Ya Zhang ◽  
Xiangchun Zhang ◽  
Qing Yuan ◽  
Wenchao Niu ◽  
Chunyu Zhang ◽  
...  

Anticancer metallodrugs that aim to physiological characters unique to tumor microenvironment are expected to combat drug tolerance and side-effects. Recently, owing to the fact that reactive oxygen species’ is closely related to the development of tumors, people are committed to developing metallodrugs with the capacity of improving the level of reactive oxygen species level toinduce oxidative stress in cancer cells. Herein, we demonstrated that peptide templated gold clusters with atomic precision preferably catalyze the transformation of hydrogen peroxide into superoxide anion in oxidative pressure-type tumor cells. Firstly, we successfully constructed gold clusters by rationally designing peptide sequences which targets integrin ανβ3 overexpressed on glioblastoma cells. The superoxide anion, radical derived from hydrogen peroxide and catalyzed by gold clusters, was confirmed in vitro under pseudo-physiological conditions. Then, kinetic parameters were evaluated to verify the catalytic properties of gold clusters. Furthermore, these peptide decorated clusters can serve as special enzyme-like catalyst to convert endogenous hydrogen peroxide into superoxide anion, elevated intracellular reactive oxygen species levels, lower mitochondrial membrane potential, damage biomacromolecules, and trigger tumor cell apoptosis consequently.


2011 ◽  
Vol 1 (7) ◽  
pp. 232 ◽  
Author(s):  
Xican Li ◽  
Xiaozhen Wang ◽  
Dongfeng Chen ◽  
Shuzhi Chen

Background: Protocatechuic acid (PCA) is a natural phenolic acid widely distributed in plants and is considered as an active component of some traditional Chinese herbal medicines such as Cibotium barometz (L.) J.Sm, Stenoloma chusanum (L.) Ching, Ilex chinensis Sims. PCA was reported to possess various pharmacological effects which may be closely correlated with its antioxidant activities. However, the antioxidant of PCA has not been investigated systematically yet. Methods: In the study, the antioxidant activities of protocatechuic acid were measured in vitro using various antioxidant assays including 1,1-diphenyl-2-picryl-hydrazyl (DPPH•), 2,2’-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS+•), superoxide anion radicals (•O2-) and hydroxyl radical (•OH) scavenging activity, ferric ions (Fe3+) and cupric ions (Cu2+) reducing power, ferrous ions (Fe2+) and cupric ions (Cu2+) chelating activity, compared with the positive controls Trolox or BHT.Results: In all assays, PCA along with positive controls exhibited dose-dependently antioxidant ability. Comparing to a standard antioxidant Trolox, the relative antioxidant activity of PCA (i.e. the ratio of IC50(Trolox)/IC50(PCA) ) was calculated as 2.8, 2.3, 3.7, 6.1, 4.2, 1.0, 2.7, 1.5, respectively, for DPPH, ABTS, reducing power (Fe3+), reducing power (Cu2+), superoxide anion radical-scavenging, hydroxyl radical-scavenging, chelating ability (Fe2+) and chelating ability (Cu2+). Conclusion: Comparing to Trolox, PCA shows much more effective antioxidant activity in vitro in both lipid and aqueous media. Hence, it could therefore be used in pharmacological or food industry as a natural antioxidant. It may exhibit antioxidant activity by both chelating metal transition ions as well as by scavenging free radicals via donating hydrogen atom (H•) or electron (e).Keywords: Protocatechuic acid, antioxidant, reducing power, free radical-scavenging, chelating ability.


Pteridines ◽  
2002 ◽  
Vol 13 (4) ◽  
pp. 140-143 ◽  
Author(s):  
Günter Weiss ◽  
Antonio Diez-Ruiz ◽  
Christian Murr ◽  
Igor Theur ◽  
Dietmar Fuchs

Abstract Upon stimulation with interferon-γ, a typical Thl cell-derived cytokine, human monocyte-dertved macrophages produce neopterin derivatives and in parallel degrade the essential amino acid L-tryptophan to L-kynurenine and subsequently to 3-hydroxyanthramlic acid and anthramlic acid. In parallel, stimulated macrophages produce reactive oxygen species such as hydrogen peroxide and hypochlorous acid. Earlier, neopterin and 7.8-dihydroneoptenn were found to enhance or decrease effects of reactive oxygen species in vitro, depending on concentration and on environmental condition. In this study, we investigated the ability of tryptophan and its metabolites to interfere with radicals in vitro by means of a chemiluminiseence-based assay system. When using hydrogen peroxide or chloramine Τ as source for radical formation. L-tryptophan and its catabolites reduced chennluminescence according to a dose-response relationship, 3-hydroxvanthranilic acid being the most efficient compound. Apart from L-kynurenme the scavenging effects of tryptophan and its metabolites were not affected by changes m pH from 5.5 to 7.5. Our data indicate that tryptophan degradation produces metabolites with a high scavenging ability for reactive oxygen and chlorine species, thereby establishing a self-regulatory mechanism to limit the tissue damage by reactive radicals produced by macrophages.


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