Reducing oxidative stress in sweet cherry fruit byPichia membranaefaciens: a possible mode of action againstPenicillium expansum

The use of chemical herbicides could not only potentially induce negative impacts on the environment, animals, and human health, but also increase the weed resistance to herbicides. In this context, the use of plant extracts could be an interesting and natural alternative to chemical products. It is important to understand the mode of action of their bioactive compounds. This is why we have studied the herbicidal effect of Cynara cardunculus crude extract in terms of inhibition of weeds’ seedling growth and its impact on physiological parameters of treated plantlets, like conductivity, dry weight, and fluorescence, and biochemical parameters linked to oxidative stress. We have observed that C. cardunculus crude extract induces oxidative stress in the treated plants and consequently disturbs the physiological and biochemical functions of the plant cells. We have investigated the herbicidal activity of three bioactive compounds, naringenin, myricitrin, and quercetin, from the C. cardunculus crude extract. In both pre- and post-emergence trials, naringenin and myricitrin were significantly more phytotoxic than quercetin. We suggest that their differential initial interaction with the plant’s plasma membrane could be one of the main signals for electrolyte leakage and production of high levels of phenoxyl radicals.

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The Effect of Lithium on Inflammation-Associated Genes in Lipopolysaccharide-Activated Raw 264.7 Macrophages

International Journal of Inflammation ◽

10.1155/2020/8340195 ◽

2020 ◽

Vol 2020 ◽

pp. 1-18 ◽

Cited By ~ 1

Author(s):

Raymond T. Makola ◽

Vusi G. Mbazima ◽

Matlou P. Mokgotho ◽

Vincent S. Gallicchio ◽

Thabe M. Matsebatlela

Keyword(s):

Oxidative Stress ◽

Mrna Expression ◽

Mode Of Action ◽

Nuclear Translocation ◽

Glycogen Synthase ◽

Bipolar Disorders ◽

No Production ◽

Raw 264.7 ◽

Activated Macrophages ◽

Raw 264.7 Macrophages

Lithium remains the preferred Food and Drug Administration- (FDA-) approved psychiatric drug for treatment of bipolar disorders since its medical establishment more than half a century ago. Recent studies revealed a promising role for lithium in the regulation of inflammation, oxidative stress, and neurodegeneration albeit unclear about its exact mode of action. Thus, the intention of this study is to delineate the regulatory mechanisms of lithium on oxidative stress in lipopolysaccharide- (LPS-) activated macrophages by evaluating its effects on nuclear factor-κB (NF-κB) activity and mRNA expression of multiple oxidative stress-related NF-κB genes. Raw 264.7 macrophages were treated with up to 10 mM lithium, and no change in cell proliferation, viability, growth, and cell adhesion was observed in real time. Pretreatment with low doses of lithium was shown to reduce nitric oxide (NO) production in LPS-activated macrophages. A reduced internal H2DCFDA fluorescence intensity, indicative of reduced reactive oxygen species (ROS) production, was observed in LPS-activated Raw 264.7 macrophages treated with lithium. Lithium has been shown to lower the production of the chemokine RANTES; furthermore, this inhibitory action of lithium has been suggested to be independent of glycogen synthase kinase-3 β (GSK3β) activity. It is shown here that lithium modulates the expression of several inflammatory genes including IκB-α, TRAF3, Tollip, and NF-κB1/p50 which are regulators of the NF-κB pathway. Moreover, lithium inhibits NF-κB activity by lowering nuclear translocation of NF-κB in LPS-activated macrophages. This is the first study to associate Tollip, Traf-3, and IκB-α mRNA expression with lithium effect on NF-κB activity in LPS-activated Raw 264.7 macrophages. Although these effects were obtained using extratherapeutic concentrations of lithium, results of this study provide useful information towards understanding the mode of action of lithium. This study associates lithium with reduced oxidative stress in LPS-activated Raw 264.7 macrophages and further suggests candidate molecular targets for the regulation of oxidative stress-related diseases using lithium beyond bipolar disorders.

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Arsenic-Induced Carcinogenesis—Oxidative Stress as a Possible Mode of Action and Future Research Needs for More Biologically Based Risk Assessment

Chemical Research in Toxicology ◽

10.1021/tx900343d ◽

2010 ◽

Vol 23 (2) ◽

pp. 327-335 ◽

Cited By ~ 146

Author(s):

Kirk T. Kitchin ◽

Rory Conolly

Keyword(s):

Oxidative Stress ◽

Risk Assessment ◽

Mode Of Action ◽

Future Research ◽

Research Needs

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Trypanocidal Activity of Melamine-Based Nitroheterocycles

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.48.5.1733-1738.2004 ◽

2004 ◽

Vol 48 (5) ◽

pp. 1733-1738 ◽

Cited By ~ 39

Author(s):

Mhairi L. Stewart ◽

Gorka Jimenez Bueno ◽

Alessandro Baliani ◽

Burkhard Klenke ◽

Reto Brun ◽

...

Keyword(s):

Oxidative Stress ◽

Mammalian Cell ◽

Mode Of Action ◽

Genotoxic Effect ◽

Null Mutant ◽

Compound A ◽

African Trypanosomes ◽

Trypanocidal Activity ◽

Adenosine Transport

ABSTRACT A series of nitroheterocyclic compounds were designed with linkages to melamine or benzamidine groups that are known substrates of the P2 aminopurine and other transporters in African trypanosomes of the brucei group. Several compounds showed in vitro trypanotoxicity with 50% inhibitory concentrations in the submicromolar range. Although most compounds interacted with the P2 transporter, as judged by their ability to inhibit adenosine transport via this carrier, uptake through this route was not necessary for activity since TbAT1-null mutant parasites, deficient in this transporter, retained sensitivity to these drugs. One compound, a melamine-linked nitrofuran, also showed pronounced activity against parasites in mice. Studies into the mode of action of this compound indicated that neither reductive, nor oxidative, stress were related to its trypanocidal activity ruling out a genotoxic effect in T. brucei, distinguishing it from some other, mammalian cell toxic, trypanocidal nitroheterocycles.

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Insights Into the Mode of Action of the Anti-Candida Activity of 1,10-Phenanthroline and its Metal Chelates

Metal-Based Drugs ◽

10.1155/mbd.2000.185 ◽

2000 ◽

Vol 7 (4) ◽

pp. 185-193 ◽

Cited By ~ 72

Author(s):

Malachy McCann ◽

Majella Geraghty ◽

Michael Devereux ◽

Denis O'Shea ◽

James Mason ◽

...

Keyword(s):

Oxidative Stress ◽

Candida Albicans ◽

Metal Complexes ◽

Mode Of Action ◽

Metal Chelates ◽

Phen Ligand ◽

Chelating Ligands ◽

Metal Free ◽

Highly Active

Metal complexes of malonie acid (metal = Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Ag(I)) were prepared and only the Ag(I) complex inhibited the growth of Candida albicans. Malonate complexes incorporating the chelating 1,10-phenanthroline (1,10-phen) ligand showed a range of activities: good (Mn(II), Cu(II), Ag(I)); moderate (Zn(II)); poor (Co(II), Ni(II)). Metal-free 1,10-phen and Ag(CH3CO2) were also highly active. The metal-free non-chelating ligands 1,7- phenanthroline and 4,7-phenanthroline were inactive and the Cu(II), Mn(II) and Zn(II) complexs of 1,7-phen displayed only marginal activity. Whereas the Cu(II) malonate/1,10-phen complex induces significant cellular oxidative stress the Zn(II) analogue does not.

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