scholarly journals Analyses of Antioxidative Properties of Selected Cyclitols and Their Mixtures with Flavanones and Glutathione

Molecules ◽  
2021 ◽  
Vol 27 (1) ◽  
pp. 158
Author(s):  
Joanna Płonka ◽  
Joanna Szablińska-Piernik ◽  
Bogusław Buszewski ◽  
Irena Baranowska ◽  
Lesław B. Lahuta

The conditions for determining the antioxidant properties of cyclitols (d-pinitol, l-quebrachitol, myo-, l-chiro-, and d-chiro-inositol), selected flavanones (hesperetin, naringenin, eriodictyol, and liquiritigenin) and glutathione by spectrophotometric methods—CUPRAC and with DPPH radical, and by a chromatographic method DPPH-UHPLC-UV, have been identified. Interactions of the tested compounds and their impact on the ox-red properties were investigated. The RSA (%) of the compounds tested was determined. Very low antioxidative properties of cyclitols, compared with flavanones and glutathione alone, were revealed. However, a significant increase in the determined antioxidative properties of glutathione by methyl-ether derivatives of cyclitols (d-pinitol and l-quebrachitol) was demonstrated for the first time. Thus, cyclitols seem to be a good candidate for creating drugs for the treatment of many diseases associated with reactive oxygen species (ROS) generation.

2020 ◽  
Author(s):  
Liang Sun ◽  
Anuj K. Sharma ◽  
Byung-Hee Han ◽  
Liviu M. Mirica

<p>Alzheimer's disease (AD) is the most common neurodegenerative disorder, yet the cause and progression of this disorder are not completely understood. While the main hallmark of AD is the deposition of amyloid plaques consisting of the β-amyloid (Aβ) peptide, transition metal ions are also known to play a significant role in disease pathology by expediting the formation of neurotoxic soluble β-amyloid (Aβ) oligomers, reactive oxygen species (ROS), and oxidative stress. Thus, bifunctional metal chelators that can control these deleterious properties are highly desirable. Herein, we show that amentoflavone (AMF) – a natural biflavonoid compound, exhibits good metal-chelating properties, especially for chelating Cu<sup>2+</sup> with very high affinity (pCu<sub>7.4</sub> = 10.44). In addition, AMF binds to Aβ fibrils with a high affinity (<i>K<sub>i</sub></i> = 287 ± 20 nM) – as revealed by a competition thioflavin T (ThT) assay, and specifically labels the amyloid plaques <i>ex vivo</i> in the brain sections of transgenic AD mice – as confirmed via immunostaining with an Ab antibody. The effect of AMF on Aβ<sub>42</sub> aggregation and disaggregation of Aβ<sub>42</sub> fibrils was also investigated, to reveal that AMF can control the formation of neurotoxic soluble Aβ<sub>42</sub> oligomers, both in absence and presence of metal ions, and as confirmed via cell toxicity studies. Furthermore, an ascorbate consumption assay shows that AMF exhibits potent antioxidant properties and can chelate Cu<sup>2+</sup> and significantly diminish the Cu<sup>2+</sup>-ascorbate redox cycling and reactive oxygen species (ROS) formation. Overall, these studies strongly suggest that AMF acts as a bifunctional chelator that can interact with various Aβ aggregates and reduce their neurotoxicity, can also bind Cu<sup>2+</sup> and mediate its deleterious redox properties, and thus AMF has the potential to be a lead compound for further therapeutic agent development for AD. </p>


Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1586
Author(s):  
Svetlana Veselova ◽  
Tatyana Nuzhnaya ◽  
Guzel Burkhanova ◽  
Sergey Rumyantsev ◽  
Igor Maksimov

Reactive oxygen species (ROS) play a central role in plant immune responses. The most important virulence factors of the Stagonospora nodorum Berk. are multiple fungal necrotrophic effectors (NEs) (SnTox) that affect the redox-status and cause necrosis and/or chlorosis in wheat lines possessing dominant susceptibility genes (Snn). However, the effect of NEs on ROS generation at the early stages of infection has not been studied. We studied the early stage of infection of various wheat genotypes with S nodorum isolates -Sn4VD, SnB, and Sn9MN, carrying a different set of NE genes. Our results indicate that all three NEs of SnToxA, SnTox1, SnTox3 significantly contributed to cause disease, and the virulence of the isolates depended on their differential expression in plants (Triticum aestivum L.). The Tsn1–SnToxA, Snn1–SnTox1and Snn3–SnTox3 interactions played an important role in inhibition ROS production at the initial stage of infection. The Snn3–SnTox3 inhibited ROS production in wheat by affecting NADPH-oxidases, peroxidases, superoxide dismutase and catalase. The Tsn1–SnToxA inhibited ROS production in wheat by affecting peroxidases and catalase. The Snn1–SnTox1 inhibited the production of ROS in wheat by mainly affecting a peroxidase. Collectively, these results show that the inverse gene-for gene interactions between effector of pathogen and product of host sensitivity gene suppress the host’s own PAMP-triggered immunity pathway, resulting in NE-triggered susceptibility (NETS). These results are fundamentally changing our understanding of the development of this economical important wheat disease.


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii17-ii17
Author(s):  
Shashank Hambarde ◽  
Martyn Sharpe ◽  
David Baskin ◽  
Santosh Helekar

Abstract Noninvasive cancer therapy with minimal side effects would be ideal for improving patient outcome in the clinic. We have developed a novel therapy using strong rotating magnets mounted on a helmet. They generate oscillating magnetic fields (OMF) that penetrate through the skull and cover the entire brain. We have demonstrated that OMF can effectively kill patient derived glioblastoma (GBM) cells in cell culture without having cytotoxic effects on cortical neurons and normal human astrocytes (NHA). Exposure of GBM cells to OMF reduced the cell viability by 33% in comparison to sham-treated cells (p&lt; 0.001), while not affecting NHA cell viability. Time lapse video-microscopy for 16 h after OMF exposure showed a marked elevation of mitochondrial reactive oxygen species (ROS), and rapid apoptosis of GBM cells due to activation of caspase 3. Addition of a potent antioxidant vitamin E analog Trolox effectively blocked OMF-induced GBM cell death. Furthermore, OMF significantly potentiated the cytotoxic effect of the pro-oxidant Benzylamine. The results of our studies demonstrate that OMF-induced cell death is mediated by ROS generation. These results demonstrate a potent oncolytic effect on GBM cells that is novel and unrelated to any previously described therapy, including a very different mechanism of action and different technology compared to Optune therapy. The effect is very powerful, and unlike Optune, can be seen within hours after initiation of treatment. We believe that this technology holds great promise for new, effective and nontoxic treatment of glioblastoma.


2021 ◽  
Author(s):  
Małgorzata Olszowy-Tomczyk

AbstractOxidative stress, associated with an imbalance between the oxidants (reactive oxygen species) and the antioxidants in the body, contributes to the development of many diseases. The body’s fight against reactive oxygen species is supported by antioxidants. Nowadays, there are too many analytical methods, but there is no one universal technique for assessing antioxidant properties. Moreover, the applied different ways of expressing the results lead to their incompatibility and unreasonable interpretation. The paper is a literature review concerning the most frequent ways of antioxidant activities expression and for an easy and universal method of the obtained results discussion. This paper is an attempt to point out their disadvantages and advantages. The manuscript can support the searching interpretation of the obtained results which will be a good tool for the development of a number of fields, especially medicine what can help in the future detection and treatment of many serious diseases. Graphic abstract


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Sumitra Miriyala ◽  
Manikandan Panchatcharam ◽  
Meera Ramanujam ◽  
Rengarajulu Puvanakrishnan

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.


2021 ◽  
Vol 22 (3) ◽  
pp. 1106
Author(s):  
Rayan Bou-Fakhredin ◽  
Batoul Dia ◽  
Hilda E. Ghadieh ◽  
Stefano Rivella ◽  
Maria Domenica Cappellini ◽  
...  

Oxidative damage by reactive oxygen species (ROS) is one of the main contributors to cell injury and tissue damage in thalassemia patients. Recent studies suggest that ROS generation in non-transfusion-dependent (NTDT) patients occurs as a result of iron overload. Among the different sources of ROS, the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase family of enzymes and cytochrome P450 (CYP450) have been proposed to be major contributors for oxidative stress in several diseases. However, the sources of ROS in patients with NTDT remain poorly understood. In this study, Hbbth3/+ mice, a mouse model for β-thalassemia, were used. These mice exhibit an unchanged or decreased expression of the major NOX isoforms, NOX1, NOX2 and NOX4, when compared to their C57BL/6 control littermates. However, a significant increase in the protein synthesis of CYP4A and CYP4F was observed in the Hbbth3/+ mice when compared to the C57BL/6 control mice. These changes were paralleled by an increased production of 20-hydroxyeicosatetraenoic acid (20-HETE), a CYP4A and CYP4F metabolite. Furthermore, these changes corroborate with onset of ROS production concomitant with liver injury. To our knowledge, this is the first report indicating that CYP450 4A and 4F-induced 20-HETE production mediates reactive oxygen species overgeneration in Hbbth3/+ mice through an NADPH-dependent pathway.


2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Kaihua Ji ◽  
Lianying Fang ◽  
Hui Zhao ◽  
Qing Li ◽  
Yang Shi ◽  
...  

Unplanned exposure to radiation can cause side effects on high-risk individuals; meanwhile, radiotherapies can also cause injury on normal cells and tissues surrounding the tumor. Besides the direct radiation damage, most of the ionizing radiation- (IR-) induced injuries were caused by generation of reactive oxygen species (ROS). Human mesenchymal stem cells (hMSCs), which possess self-renew and multilineage differentiation capabilities, are a critical population of cells to participate in the regeneration of IR-damaged tissues. Therefore, it is imperative to search effective radioprotectors for hMSCs. This study was to demonstrate whether natural source ginger oleoresin would mitigate IR-induced injuries in human mesenchymal stem cells (hMSCs). We demonstrated that ginger oleoresin could significantly reduce IR-induced cytotoxicity, ROS generation, and DNA strand breaks. In addition, the ROS-scavenging mechanism of ginger oleoresin was also investigated. The results showed that ginger oleoresin could induce the translocation of Nrf2 to cell nucleus and activate the expression of cytoprotective genes encoding for HO-1 and NQO-1. It suggests that ginger oleoresin has a potential role of being an effective antioxidant and radioprotective agent.


2007 ◽  
Vol 2 ◽  
pp. 117739010700200 ◽  
Author(s):  
Tamara Zoltan ◽  
Franklin Vargas ◽  
Carla Izzo

We have determined and quantified spectrophotometrically the capacity of producing reactive oxygen species (ROS) as 1O2 during the photolysis with UV-A light of 5 new synthesized naphthyl ester derivates of well-known quinolone antibacterials (nalidixic acid (1), cinoxacin (2), norfloxacin (3), ciprofloxacin (4) and enoxacin (5)). The ability of the naphthyl ester derivatives (6-10) to generate singlet oxygen were detecting and for the first time quantified by the histidine assay, a sensitive, fast and inexpensive method. The following tendency of generation of singlet oxygen was observed: compounds 7 >10 > 6 > 8 > 9 >> parent drugs 1-5.


2018 ◽  
Vol 19 (12) ◽  
pp. 4078 ◽  
Author(s):  
Dahn Clemens ◽  
Michael Duryee ◽  
Cleofes Sarmiento ◽  
Andrew Chiou ◽  
Jacob McGowan ◽  
...  

Doxycycline (DOX), a derivative of tetracycline, is a broad-spectrum antibiotic that exhibits a number of therapeutic activities in addition to its antibacterial properties. For example, DOX has been used in the management of a number of diseases characterized by chronic inflammation. One potential mechanism by which DOX inhibits the progression of these diseases is by reducing oxidative stress, thereby inhibiting subsequent lipid peroxidation and inflammatory responses. Herein, we tested the hypothesis that DOX directly scavenges reactive oxygen species (ROS) and inhibits the formation of redox-mediated malondialdehyde-acetaldehyde (MAA) protein adducts. Using a cell-free system, we demonstrated that DOX scavenged reactive oxygen species (ROS) produced during the formation of MAA-adducts and inhibits the formation of MAA-protein adducts. To determine whether DOX scavenges specific ROS, we examined the ability of DOX to directly scavenge superoxide and hydrogen peroxide. Using electron paramagnetic resonance (EPR) spectroscopy, we found that DOX directly scavenged superoxide, but not hydrogen peroxide. Additionally, we found that DOX inhibits MAA-induced activation of Nrf2, a redox-sensitive transcription factor. Together, these findings demonstrate the under-recognized direct antioxidant property of DOX that may help to explain its therapeutic potential in the treatment of conditions characterized by chronic inflammation and increased oxidative stress.


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