scholarly journals Peptide-Templated Gold Clusters as Enzyme-Like Catalyst Boost Intracellular Oxidative Pressure and Induce Tumor-Specific Cell Apoptosis

Nanomaterials ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 1040 ◽  
Author(s):  
Ya Zhang ◽  
Xiangchun Zhang ◽  
Qing Yuan ◽  
Wenchao Niu ◽  
Chunyu Zhang ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Hydrogen Peroxide ◽  
Cell Apoptosis ◽  
Superoxide Anion ◽  
Reactive Oxygen ◽  
Gold Clusters ◽  
Specific Cell ◽  
Oxygen Species ◽  
Potential Damage

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.

scholarly journals Sulphamoylated Estradiol Analogue Induces Reactive Oxygen Species Generation to Exert Its Antiproliferative Activity in Breast Cancer Cell Lines

Molecules ◽  
2020 ◽  
Vol 25 (18) ◽  
pp. 4337
Author(s):  
Maphuti T. Lebelo ◽  
Anna M. Joubert ◽  
Michelle H. Visagie
Keyword(s):  
Reactive Oxygen Species ◽  
Hydrogen Peroxide ◽  
Superoxide Anion ◽  
Fluorescent Microscopy ◽  
Reactive Oxygen ◽  
Breast Cancer Cell Lines ◽  
Oxygen Species ◽  
Morphological Studies ◽  
Mcf 7

2-Methoxyestradiol (2ME), a 17β-estradiol metabolite, exerts anticancer properties in vitro and in vivo. To address 2ME’s low bioavailability, research led to the in silico design of sulphamoylated 2ME analogues. However, the role of oxidative stress induced in the activity exerted by sulphamoylated compounds remains elusive. In the current study, the influence of 2-Ethyl-17-oxoestra-1,3,5(10)-trien-3-yl sulphamate (ESE-one) on reactive oxygen species (ROS) induction and its effect on cell proliferation, as well as morphology, were assessed in breast tumorigenic cells (MCF-7 and MDA-MB-231). Fluorescent microscopy showed that sulphamoylated estradiol analogues induced hydrogen peroxide and superoxide anion, correlating with decreased cell growth demonstrated by spectrophotometry data. ESE-one exposure resulted in antiproliferation which was repressed by tiron (superoxide inhibitor), trolox (peroxyl inhibitor) and N,N′-dimethylthiourea (DMTU) (hydrogen peroxide inhibitor). Morphological studies demonstrated that tiron, trolox and DMTU significantly decreased the number of rounded cells and shrunken cells in MCF-7 and MDA-MB-231 cells induced by ESE-one. This in vitro study suggests that ESE-one induces growth inhibition and cell rounding by production of superoxide anion, peroxyl radical and hydrogen peroxide. Identification of these biological changes in cancer cells caused by sulphamoylated compounds hugely contributes towards improvement of anticancer strategies and the ROS-dependent cell death pathways in tumorigenic breast cells.

scholarly journals A Novel Tetrapeptide Derivative Exhibits In Vitro Inhibition of Neutrophil-Derived Reactive Oxygen Species and Lysosomal Enzymes Release

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Sumitra Miriyala ◽  
Manikandan Panchatcharam ◽  
Meera Ramanujam ◽  
Rengarajulu Puvanakrishnan
Keyword(s):  
Reactive Oxygen Species ◽  
Superoxide Anion ◽  
Lysosomal Enzymes ◽  
Reactive Oxygen ◽  
Peptide Sequence ◽  
Ros Generation ◽  
Oxygen Species ◽  
Complement Factors

Neutrophil infiltration plays a major role in the pathogenesis of myocardial injury. Oxidative injury is suggested to be a central mechanism of the cellular damage after acute myocardial infarction. This study is pertained to the prognostic role of a tetrapeptide derivative PEP1261 (BOC-Lys(BOC)-Arg-Asp-Ser(tBu)-OtBU), a peptide sequence (39–42) of lactoferrin, studied in the modulation of neutrophil functions in vitro by measuring the reactive oxygen species (ROS) generation, lysosomal enzymes release, and enhanced expression of C proteins. The groundwork experimentation was concerned with the isolation of neutrophils from the normal and acute myocardial infarct rats to find out the efficacy of PEP1261 in the presence of a powerful neutrophil stimulant, phorbol 12-myristate 13 acetate (PMA). Stimulation of neutrophils with PMA resulted in an oxidative burst of superoxide anion and enhanced release of lysosomal enzymes and expression of complement proteins. The present study further demonstrated that the free radicals increase the complement factors in the neutrophils confirming the role of ROS. PEP1261 treatment significantly reduced the levels of superoxide anion and inhibited the release of lysosomal enzymes in the stimulated control and infarct rat neutrophils. This study demonstrated that PEP1261 significantly inhibited the effect on the ROS generation as well as the mRNA synthesis and expression of the complement factors in neutrophils isolated from infarct heart.

Tryptophan Metabolites as Scavengers of Reactive Oxygen and Chlorine Species

Pteridines ◽  
2002 ◽  
Vol 13 (4) ◽  
pp. 140-143 ◽  
Author(s):  
Günter Weiss ◽  
Antonio Diez-Ruiz ◽  
Christian Murr ◽  
Igor Theur ◽  
Dietmar Fuchs
Keyword(s):  
Reactive Oxygen Species ◽  
Hydrogen Peroxide ◽  
Hypochlorous Acid ◽  
Reactive Oxygen ◽  
Human Monocyte ◽  
Interferon Γ ◽  
Oxygen Species ◽  
Tryptophan Degradation ◽  
Tryptophan Metabolites

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.

scholarly journals Reactive oxygen species in disease: Rebuttal of a conventional concept

2015 ◽  
Vol 1 (1) ◽  
pp. 23-27
Author(s):  
Luis Vitetta ◽  
Samantha Coulson ◽  
Anthony W Linnane
Keyword(s):  
Nitric Oxide ◽  
Reactive Oxygen Species ◽  
Hydrogen Peroxide ◽  
Nucleic Acids ◽  
Superoxide Anion ◽  
Reactive Oxygen ◽  
Second Messenger ◽  
Normal Function ◽  
Ageing Process ◽  
Oxygen Species

The production of intracellular reactive oxygen species and reactive nitrogen species has long been proposed as leading to the random deleterious modification of macromolecules (i.e., nucleic acids, proteins) with an associated progressive development of the age associated systemic diseases (e.g., diabetes, Parkinson’s disease) as well as contributing to the ageing process.   Superoxide anion (hydrogen peroxide) and nitric oxide (peroxynitrite) comprise regulated intracellular second messenger pro-oxidant systems, with specific sub-cellular locales of production and are essential for the normal function of the metabolome and cellular electro-physiology.  We have posited that the formation of superoxide anion and its metabolic product hydrogen peroxide, and nitric oxide, do not conditionally lead to random damage of macromolecular species such as nucleic acids or proteins.  Under normal physiological conditions their production is intrinsically regulated that is very much consistent with their second messenger purpose of function.   We further propose that the concept of an orally administered small molecule antioxidant as a therapy to abrogate free radical activity (to control oxidative stress) is a chimera.  As such we consider that free radicals are not a major overwhelming player in the development of the chronic diseases or the ageing process.        

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