Free Radical Research最新文献

{"title":"Decreased plasma H₂O₂ levels are associated with the pathogenesis leading to COVID-19 worsening and mortality.","authors":"Liara Freitas Cavalcanti,&nbsp;Isabela Chagas Silva,&nbsp;Thiago Henrique Daniel do Nascimento,&nbsp;Jôse de Melo,&nbsp;Cintia Magalhães Carvalho Grion,&nbsp;Alessandra Lourenço Cecchini,&nbsp;Rubens Cecchini","doi":"10.1080/10715762.2023.2174021","DOIUrl":"https://doi.org/10.1080/10715762.2023.2174021","url":null,"abstract":"<p><p>Oxidative Stress (OS) is involved in the pathogenesis of COVID-19 and in the mechanisms by which SARS-CoV-2 causes injuries to tissues, leading to cytopathic hypoxia and ultimately multiple organ failure. The measurement of blood glutathione (GSH), H₂O₂, and catalase activity may help clarify the pathophysiology pathways of this disease. We developed and standardized a sensitive and specific chemiluminescence technique for H₂O₂ and GSH measurement in plasma and red blood cells of COVID-19 patients admitted to the intensive care unit (ICU). Contrary to what was expected, the plasma concentration of H₂O₂ was substantially reduced (10-fold) in COVID-19 patients compared to the healthy control group. From the cohort of patients discharged from the hospital and those who were deceased, the former showed a 3.6-fold and the later 16-fold H₂O₂ reduction compared to the healthy control. There was a 4.4 reduction of H₂O₂ concentration in the deceased group compared to the discharged group. Interestingly, there was no variation in GSH levels between groups, and reduced catalase activity was found in discharged and deceased patients compared to control. These data represent strong evidence that H₂O₂ is converted into highly reactive oxygen species (ROS), leading to the worst prognosis and death outcome in COVID-19 patients admitted to ICU. Considering the difference in the levels of H₂O₂ between the control group and the deceased patients, it is proposed the quantification of plasma H₂O₂ as a marker of disease progression and the induction of the synthesis of antioxidant enzymes as a strategy to reduce the production of oxidative stress during severe COVID-19.HighlightsH₂O₂ plasma levels is dramatically reduced in patients who deceased compared to those discharged and to the control group.Plasmatic quantification of H₂O₂ can be possibly used as a predictor of disease progression.Catalase activity is reduced in COVID-19.GSH levels remain unchanged in COVID-19 compared to the control group.</p>","PeriodicalId":12411,"journal":{"name":"Free Radical Research","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9073420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transferrin-mediated increase of labile iron Pool following simulated ischemia causes lipid peroxidation during the early phase of reperfusion.","authors":"Dongju Lee,&nbsp;Euncheol Son,&nbsp;Young-Hoon Kim","doi":"10.1080/10715762.2023.2169683","DOIUrl":"https://doi.org/10.1080/10715762.2023.2169683","url":null,"abstract":"<p><p>Heart ischemia/reperfusion (I/R) injury is related to iron content. However, the occurrence and mechanism of changes in labile iron pool (LIP) during I/R is debatable. Moreover, the identity of the iron form dominant in LIP during I/R is unclear. Herein, we measured changes of LIP during simulated ischemia (SI) and reperfusion (SR), in which ischemia was simulated <i>in vitro</i> with lactic acidosis and hypoxia. Total LIP did not change in lactic acidosis, whereas LIP, especially Fe³⁺, increased in hypoxia. Under SI, accompanied by hypoxia with acidosis, both Fe²⁺ and Fe³⁺ were significantly increased. Increased total LIP was maintained at 1 h post-SR. However, the Fe²⁺ and Fe³⁺ portion was changed. The increased Fe²⁺ was decreased, and conversely the Fe³⁺ was increased. BODIPY oxidized signal increased and through the time-course these changes correlated with blebbing of cell membrane and SR-induced LDH release. These data suggested lipid peroxidation occurred <i>via</i> Fenton's reaction. The experiments using bafilomycin A1 and zinc protoporphyrin suggested no role of ferritinophagy or heme oxidation in the increase of LIP during SI. The extracellular source, transferrin assessed using serum transferrin bound iron (TBI) saturation showed that the depletion of TBI reduced SR-induced cell damages and additive saturation of TBI accelerated SR-induced lipid peroxidation. Furthermore, Apo-Tf dramatically blocked the increase of LIP and SR-induced damages. In conclusion, Tf-mediated iron induces the increase of LIP during SI, and it causes Fenton reaction-mediated lipid peroxidation during the early phase of SR.</p>","PeriodicalId":12411,"journal":{"name":"Free Radical Research","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9080308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Urinary 8-oxoGuo as a potential novel evaluation index for patients with nephrotic syndrome.","authors":"Zhen Liu,&nbsp;Jing-Jing Wang,&nbsp;Qian Liu,&nbsp;Jin Li,&nbsp;Shan Jiang,&nbsp;Ya-Qing Ma,&nbsp;Ya-Min Dang,&nbsp;Jian-Ping Cai","doi":"10.1080/10715762.2023.2166504","DOIUrl":"https://doi.org/10.1080/10715762.2023.2166504","url":null,"abstract":"<p><p>Urinary 8-oxo-7,8-dihydroguanosine (8-oxoGuo) and 8-oxo-7,8-dihydro-2'- deoxyguanosine (8-oxodGuo) are considered biomarkers of oxidative stress, and patients with nephrotic syndrome have been reported to have increased oxidative stress levels. In this study, we aimed to assess the value of 8-oxoGuo and 8-oxodGuo as novel biomarkers to evaluate the severity of nephrotic syndrome. In total, 107 patients with nephrotic syndrome and 116 healthy controls were recruited for this study. The concentrations of urinary 8-oxoGuo and 8-oxodGuo were measured using isotope-labeled liquid chromatography with tandem mass spectrometry. Urinary creatinine was used to regulate 8-oxoGuo and 8-oxodGuo concentrations. Urinary 8-oxoGuo and 8-oxoGuo/Cr levels in patients with nephrotic syndrome were significantly higher than those in healthy control participants. 8-oxoGuo/Cr showed a positive correlation with the 24 h urinary total protein (UTP) and UTP levels and negative correlations with serum total protein and albumin levels. After treatment, urinary 8-oxoGuo and 8-oxoGuo/Cr levels were significantly lower in the group with a low 24 h-UTP value (<3.5 g/d) than in the high value group. 8-oxoGuo can be used as a feasible and reliable biomarker for the assessment of nephrotic syndrome.HighlightsUrinary 8-oxoGuo level was significantly increased in patients with nephrotic syndrome.Urinary 8-oxoGuo level increased with an increase in plasma protein and a decrease in urine protein.Urinary 8-oxoGuo level decreased with nephrotic syndrome remission when urinary microalbumin showed no significant change.Urinary 8-oxoGuo level can be used as novel biomarkers of nephrotic syndrome.</p>","PeriodicalId":12411,"journal":{"name":"Free Radical Research","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9087997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Guaiacol oxidation: theoretical insight into thermochemistry of radical processes involving methoxy group demethylation.","authors":"Monika Biela,&nbsp;Andrea Kleinová,&nbsp;Erik Klein","doi":"10.1080/10715762.2023.2170880","DOIUrl":"https://doi.org/10.1080/10715762.2023.2170880","url":null,"abstract":"<p><p>Guaiacol (2-methoxyphenol) is naturally occurring phenolic compound essential in various research areas. Oxidative transformation of guaiacol can lead to the formation of various products, including 1,3-benzodioxole or <i>ortho</i>-quinone. Therefore, this study is focused on the investigation of the reaction enthalpies of experimentally observed guaiacol oxidation pathways in gas-phase, as well as in non-polar environment and aqueous solution. Corresponding Density Functional Theory (DFT) calculations were carried out using two hybrid functionals (M06-2X and B3LYP-D3). All reaction enthalpies, as well as Gibbs free energies, were also calculated using composite <i>ab initio</i> G4 method. M06-2X and G4 results show mutual agreement and the best accordance with available experimentally determined reaction enthalpies. Obtained Gibbs free reaction energies indicate that formation of <i>ortho</i>-quinone is thermodynamically preferred to formation of 1,3-benzodioxole at 298 K in studied environments. Moreover, all computational methods confirm that the reaction enthalpy of methoxy group demethylation, i.e. O-C bond dissociation enthalpy (BDE), is substantially lower in comparison to the enthalpy of hydrogen atom transfer from phenolic OH group. In the case of phenoxide anion of guaiacol, which can be formed in ionization supporting solvents, O-C BDE shows further significant decrease, exceeding 50 kJ mol^-1, in comparison to parent molecule.HIGHLIGHTSReaction enthalpies and Gibbs free energies of individual steps of guaiacol transformation to 1,3-benzodioxole or <i>ortho-</i>quinone are studied in three environments.M06-2X functional and composite <i>ab initio</i> G4 methods provide reliable O-H and O-C bond dissociation enthalpies.Dissociation enthalpy of methoxy group O-C bond is lower by ca. 100 kJ mol^-1 in comparison to phenolic O-H bond.Phenoxide anion of guaiacol shows substantially lower O-C BDE than parent molecule.</p>","PeriodicalId":12411,"journal":{"name":"Free Radical Research","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9433158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Betulinic acid mitigates oxidative stress-mediated apoptosis and enhances longevity in the yeast <i>Saccharomyces cerevisiae</i> model.","authors":"S J Sudharshan,&nbsp;Ananth Krishna Narayanan,&nbsp;Jemima Princilly,&nbsp;Madhu Dyavaiah,&nbsp;Dinesh A Nagegowda","doi":"10.1080/10715762.2023.2166505","DOIUrl":"https://doi.org/10.1080/10715762.2023.2166505","url":null,"abstract":"<p><p>Betulinic acid (BA), a pentacyclic triterpenoid found in certain plant species, has been reported to have several health benefits including antioxidant and anti-apoptotic properties. However, the mechanism by which BA confers these properties is currently unknown. <i>Saccharomyces cerevisiae</i>, a budding yeast with a short life cycle and conserved cellular mechanism with high homology to humans, was used as a model for determining the role of BA in aging and programmed cell death (PCD). Treatment with hydrogen peroxide (H₂O₂) exhibited significantly increased (30-35%) survivability of antioxidant (<i>sod1Δ, sod2Δ, cta1Δ, ctt1Δ, and tsa1Δ</i>) and anti-apoptotic (<i>pep4Δ and fis1Δ</i>) mutant strains when cells were pretreated with BA (30 µM) as demonstrated in spot and CFU (Colony forming units) assays. Measurement of intracellular oxidation level using the ROS-specific dye H₂DCF-DA showed that all tested BA-pretreated mutants exhibited decreased ROS than the control when exposed to H₂O₂. Similarly, when mutant strains were pretreated with BA and then exposed to H₂O₂, there was reduced lipid peroxidation as revealed by the reduced malondialdehyde content. Furthermore, BA-pretreated mutant cells showed significantly lower apoptotic activity by decreasing DNA/nuclear fragmentation and chromatin condensation under H₂O₂-induced stress as determined by DAPI and acridine orange/ethidium bromide staining. In addition, BA treatment also extended the life span of antioxidant and anti-apoptotic mutants by ∼10-25% by scavenging ROS and preventing apoptotic cell death. Our overall results suggest that BA extends the chronological life span of mutant strains lacking antioxidant and anti-apoptotic genes by lowering the impact of oxidative stress, ROS levels, and apoptotic activity. These properties of BA could be further explored for its use as a valuable nutraceutical.</p>","PeriodicalId":12411,"journal":{"name":"Free Radical Research","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9449069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of antioxidant and antiparkinsonian potential of a new diterpene isolated from <i>Croton argyrophylloides</i>.","authors":"Rafael Carneiro Bastos,&nbsp;Carlos Franciney Moreira Vasconcelos,&nbsp;Marcela Bezerra Paiva,&nbsp;Thomas Dominik de Sousa Dos Reis,&nbsp;Ricardo Basto Souza,&nbsp;Hélcio Silva Dos Santos,&nbsp;Paulo Nogueira Bandeira,&nbsp;Lissiana Magna Vasconcelos Aguiar,&nbsp;Rodrigo Maranguape Silva da Cunha","doi":"10.1080/10715762.2023.2176763","DOIUrl":"https://doi.org/10.1080/10715762.2023.2176763","url":null,"abstract":"<p><p>Oxidative stress is related to health problems including neurological and neurodegenerativedisturbs, such as Parkinson's disease. Natural compounds are reported as source of antioxidant molecules. Therefore, this study aimed to analyze the antioxidant and neuroprotective potential of a new diterpene isolated from <i>C. argyrophylloides</i> (MP-1). Male Wistar rats (250-300 g) were used to evaluate MP-1 antiparkinsonian potential through neurodegenerative model induced by the neurotoxin 6-hydroxydopamine (21 μg). On the 14th day, animals were submitted to behavioral tests and on the 15th day, brain areas were dissected to neurochemical analyzes. MP-1 demonstrated a high antioxidant capacity <i>in vitro</i> and decreased the parkinsonian effects, such as behavioral changes, motor alterations, and body weight loss. MP-1 was also able to control the upregulated levels of nitrosative stress and lipid peroxidation. These findings suggest MP-1 as a diterpene with high antioxidant capacity which might be used to development of new approach against Parkinson's disease.</p>","PeriodicalId":12411,"journal":{"name":"Free Radical Research","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9083057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Autoxidation of ascorbate mediates lysine <i>N</i>-pyrrolation.","authors":"Jun Yoshitake,&nbsp;Takahiro Shibata,&nbsp;Miho Chikazawa,&nbsp;Koji Uchida","doi":"10.1080/10715762.2023.2174865","DOIUrl":"https://doi.org/10.1080/10715762.2023.2174865","url":null,"abstract":"<p><p>Protein <i>N</i>-pyrrolation, which converts lysine residues to <i>N</i>^ε-pyrrole-l-lysine (pyrK), is a naturally occurring covalent modification. The pyrrolated proteins have a unique property of binding to DNA-staining agents, such as SYBR Green I (SG), and anti-DNA antibodies, suggesting a physiologically relevant modification that gives rise to DNA mimic protein. These properties of pyrrolated protein are suggested to be associated with innate and autoimmune responses. Short-chain aldehydes derived from lipid peroxidation are thought to be involved in the formation of pyrK. We now report that similar lysine <i>N</i>-pyrrolation also occurs during the metal-catalyzed oxidation of proteins with ascorbate. When human serum albumin (HSA) was incubated with Fe²⁺/ascorbate in the presence and absence of docosahexaenoic acid, the protein was converted to SG-binding proteins even without the polyunsaturated fatty acid. The formation of SG-binding proteins by Fe²⁺/ascorbate was accompanied by the formation of pyrK, which was also detected in ascorbate-treated hemoglobin. Moreover, the metal-catalyzed oxidation of ascorbate produced the pyrrolation factors, glycolaldehyde and glyoxal. These results and the observations that sera from autoimmune-prone MRL-<i>lpr</i> mice recognized modified proteins with Fe²⁺/ascorbate and with glycolaldehyde/glyoxal suggest that the autoxidation of ascorbate, as well as lipid peroxidation, can be a source of autoantigenic <i>N</i>-pyrrolated proteins. Our findings revealed a possible function of ascorbate as an endogenous source of pyrrolated proteins and suggested that the pyrK residues generated in proteins may play a role in the innate and autoimmune responses associated with the oxidative metabolism of ascorbate.</p>","PeriodicalId":12411,"journal":{"name":"Free Radical Research","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9080472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Beneficial effects of vitamin B₁₂ treatment in pediatric patients diagnosed with vitamin B₁₂ deficiency regarding total-native thiol, oxidative stress, and mononuclear leukocyte DNA damage.","authors":"Cem Koray Firat,&nbsp;Beyza Nur Ozkan,&nbsp;Eray Metin Guler","doi":"10.1080/10715762.2022.2162392","DOIUrl":"https://doi.org/10.1080/10715762.2022.2162392","url":null,"abstract":"<p><p>Vitamin B₁₂ is involved in biochemical metabolic pathways. B₁₂ deficiency is common in childhood when the need for the vitamin increases and growth and development occur. Various hematological, neurological, psychiatric, and gastrointestinal disorders are observed in its deficiency. In addition, B₁₂ deficiency is associated with oxidative stress and DNA damage. Therefore, the aim of our study is to evaluate oxidative stress, thiol/disulfide homeostasis, and DNA damage pre and post-treatment in children diagnosed with B₁₂ deficiency. A total of 40 children with B₁₂ deficiency were included in the study after the consent form was approved. Blood was drawn from children pre and posttreatment. Hemoglobin (HGB), hematocrit (HCT), and red blood cells (RBC) were measured by autoanalyzer; total antioxidant status (TAS), total oxidant status (TOS), total thiol (TT), and native thiol (NT) were measured by the photometric method, and DNA damage was analyzed by the comet assay method. Oxidative stress index (OSI) and disulfide (DIS) values were calculated. As a result of the experiments, HGB, HCT, and RBC increased with treatment. While TAS, TT, and NT as antioxidant parameters increased; TOS, OSI, and DIS decreased with treatment compared to pretreatment. DNA damage was also found to decrease with treatment. Additionally, these data were statistically significant (<i>p</i> < 0.001). It was found that oxidative stress and DNA damage decreased with oral B₁₂ treatment in children with B₁₂ deficiency, and clinical parameters were also improved.</p>","PeriodicalId":12411,"journal":{"name":"Free Radical Research","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10651736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MiR-125b-5p is targeted by curcumin to regulate the cellular antioxidant capacity.","authors":"Lingli Lin,&nbsp;Xi Chen,&nbsp;Xiaoting Sun,&nbsp;Baoping Xiao,&nbsp;Jian Li,&nbsp;Jingwen Liu,&nbsp;Guiling Li","doi":"10.1080/10715762.2022.2162393","DOIUrl":"https://doi.org/10.1080/10715762.2022.2162393","url":null,"abstract":"<p><p>As a natural polyphenolic food supplement and the principal curcuminoid in turmeric, curcumin shows antioxidant, anti-inflammatory, and antitumor activities. However, its specific functional mechanism remains unclear. Our preliminary study indicated that miR-125b-5p was downregulated by a curcumin extract. This study aimed to determine whether miR-125b-5p is involved in the antioxidant regulation of curcumin. The results showed that miR-125b-5p overexpression had a pro-oxidant effect by reducing the cellular antioxidant capacity, as well as decreasing the activities of catalase (CAT) and superoxide dismutase (SOD) in the normal liver cell line LO2. However, miR-125b-5p repression significantly increased the cellular antioxidant capacity and enhanced the activities of CAT and SOD. Further investigation demonstrated that the cellular antioxidant capacity induced by curcumin extract was inhibited by miR-125b-5p overexpression. Thus, curcumin may exhibit antioxidant effects by repressing miR-125b-5p expression, which provides new insights into the molecular antioxidant mechanism of curcumin and other functional food components.</p>","PeriodicalId":12411,"journal":{"name":"Free Radical Research","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9204253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-thermal plasma elicits ferrous chloride-catalyzed DMPO-OH.","authors":"Yasumasa Okazaki,&nbsp;Nanami Ito,&nbsp;Hiromasa Tanaka,&nbsp;Masaru Hori,&nbsp;Shinya Toyokuni","doi":"10.1080/10715762.2022.2157272","DOIUrl":"https://doi.org/10.1080/10715762.2022.2157272","url":null,"abstract":"<p><p>Non-thermal plasma (NTP) induces the generation of reactive oxygen species (ROS) and reactive nitrogen species, such as hydroxyl radicals (^•OH), hydrogen peroxide (H₂O₂), singlet oxygen, superoxide, ozone, and nitric oxide, at near-physiological temperatures. These molecules promote blood coagulation, wound healing, disinfection, and selective cancer cell death. Based on these evidences, clinical trials of NTP have been conducted for treating chronic wounds and head and neck cancers. Although clinical applications have progressed, the stoichiometric quantification of NTP-induced ROS remains unclear in the liquid phase in the presence of FeCl₂ or FeCl₃ in combination with biocompatible reducing agents, which may modulate the final biological effects of NTP. In this study, we employed electron paramagnetic resonance spectroscopy to quantify ROS using spin-trapping probe, 5,5-dimethyl-1-pyrroline-<i>N</i>-oxide (DMPO) and H₂O₂, using luminescent probe in the presence of FeCl₂ or FeCl₃. NTP-induced DMPO-OH levels were elevated 10-100 µM FeCl₂ or 500 and 1000 µM FeCl₃. NTP-induced DMPO-OH with 10 µM FeCl₂ or FeCl₃ was significantly scavenged by ascorbate, α-tocopherol, dithiothreitol, reduced glutathione, or oxidized glutathione, whereas dehydroascorbate was ineffective in 2 mM DMPO. NTP-induced H₂O₂ was significantly degraded by 100 µM FeCl₂ and FeCl₃ in an iron-dependent manner. Meanwhile, decomposition of H₂O₂ by catalase decayed DMPO-OH efficiently in the presence of iron, indicating iron causes DMPO-OH production and degradation simultaneously. These results suggest that NTP-induced DMPO-OH is generated by the H₂O₂-consuming, iron-dependent Fenton reaction and ferryl intermediates. The potential iron-mediated ROS production by NTP is also discussed to clarify the interaction between NTP-induced ROS and biomolecules.</p>","PeriodicalId":12411,"journal":{"name":"Free Radical Research","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10651269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}