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1.
Eur Rev Med Pharmacol Sci ; 27(1): 208-214, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36647870

RESUMO

OBJECTIVE: This study aims to investigate the level of Meteorin-like protein (METRNL) and C-reactive protein (CRP), total antioxidant status (TAS), total oxidant status (TOS), and oxidative Stress Index (OSI) which are known to be related with inflammation in patients with acute myocardial infarction (AMI). PATIENTS AND METHODS: A total of 64 patients diagnosed with AMI at the emergency service and 56 healthy controls were included in this study. Levels of METRNL, CRP, TAS, TOS, OSI, and other basic biochemical parameters and hemograms of the study groups were analyzed. RESULTS: A significant difference was found between groups in terms of level of glucose (GLU) (p<0.001), urea (p<0.001), creatinine (CRE) (p<0.001), Troponin-I (TROP) (p<0.001), CRP (p<0.001), white blood cell (WBC) (p<0.001), TAS (p<0.001), TOS (p<0.001), OSI (p<0.001) and METRNL (p<0.001). It was determined that there was a significant negative correlation between the level of METRNL with the time from the onset of chest pain until emergency department admission (r=-0.345, p=0.005) and the level of troponin (r=-0.372, p=0.002) in 64 patients diagnosed with the acute coronary syndrome (ACS). However, it was determined that a significant correlation was not present with age (r=-0.058, p=0.650), BMI (r=0.092, p=0.472), TAS (r=0.079, p=0.533), TOS (r=0.113, p=0.374), OSI (r=0.042, p=0.740), CRP (r=-0.192, p=0.129) level. When we accept the cut-off value of METRNL ≤2.55 ng/mL in ROC analysis, its sensitivity and specificity were determined as 82.81% and 80.36%, respectively in differentiating AMI patients from the healthy control group. CONCLUSIONS: It was found that the level of METRNL decreased in AMI patients and a negative correlation was present between the level of METRNL with the time from the onset of chest pain until emergency department admission and the level of troponin. In addition, it was determined that the level of TOS and OSI were significantly increased and the level of TAS decreased considerably compared to the healthy control.


Assuntos
Síndrome Coronariana Aguda , Adipocinas , Infarto do Miocárdio , Humanos , Antioxidantes/metabolismo , Proteína C-Reativa/metabolismo , Dor no Peito , Oxidantes , Estresse Oxidativo , Troponina , Adipocinas/metabolismo
2.
J Am Chem Soc ; 145(2): 1185-1193, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36592344

RESUMO

Direct functionalization of methane selectively to value-added chemicals is still one of the main challenges in modern science. Acetic acid is an important industrial chemical produced nowadays by expensive and environmentally unfriendly carbonylation of methanol using homogeneous catalysts. Here, we report a new photocatalytic reaction route to synthesize acetic acid from CH4 and CO at room temperature using water as the sole external oxygen source. The optimized photocatalyst consists of a TiO2 support and ammonium phosphotungstic polyoxometalate (NPW) clusters anchored with isolated Pt single atoms (Pt1). It enables a stable synthesis of 5.7 mmol·L-1 acetic acid solution in 60 h with the selectivity over 90% and 66% to acetic acid on liquid-phase and carbon basis, respectively, with the production of 99 mol of acetic acid per mol of Pt. Combined isotopic and in situ spectroscopy investigation suggests that synthesis of acetic acid proceeds via a photocatalytic oxidative carbonylation of methane over the Pt1 sites, with the methane activation facilitated by water-derived hydroxyl radicals.


Assuntos
Ácido Acético , Metano , Metano/química , Ácido Acético/química , Água , Oxidantes , Temperatura
3.
Sci Rep ; 13(1): 1131, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36670131

RESUMO

Oxidative stress and inflammation are hypothesised as the main contributor for Chronic Obstructive Pulmonary Disease (COPD). Cigarette smoke (CS), a major cause of COPD leads to inflammation resulting in recruitment of neutrophils and macrophages which are rich sources of oxidants. Activation of these cells produces excess oxidants and depletes antioxidants resulting in stress. Presently, effective drug for COPD is limited; therefore, novel compounds from natural sources, including plants are under exploration. The present study aims to investigate the protective effect of Ocimum sanctum leaf extract (OLE) in CS - induced model of COPD. Exposure to CS was performed thrice a week for 8 weeks and OLE (200 mg/kg and 400 mg/kg) was administered an hour before CS exposure. Control group (negative control) were exposed to ambient air while COPD group was exposed to CS (positive control). Administration of OLE doses reduced inflammation, decreased oxidant concentration and increased antioxidant concentration (p < 0.01). Molecular docking studies between the major phytocompounds of OLE (Eugenol, Cyclohexane and Caryophyllene) and antioxidant enzymes Superoxide dismutase (SOD), Catalase, Glutathione peroxidase (GPx), Glutathione reductase (GR) and Glutathione S Transferase (GST) showed strong binding interaction in terms of binding energy. In vivo and in silico findings for the first time indicates that OLE extract significantly alleviates oxidative stress by its potent free radical scavenging property and strong interaction with antioxidant enzymes. OLE extract may prove to be a therapeutic option for COPD prevention and treatment.


Assuntos
Lesão Pulmonar , Doença Pulmonar Obstrutiva Crônica , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Ocimum sanctum , Lesão Pulmonar/metabolismo , Simulação de Acoplamento Molecular , Extratos Vegetais/uso terapêutico , Oxirredução , Estresse Oxidativo , Oxidantes/metabolismo , Inflamação/metabolismo , Pulmão/metabolismo
4.
Water Res ; 230: 119562, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36603306

RESUMO

Hydrogen peroxide (H2O2) is the most commonly used oxidant in advanced oxidation processes for emerging organic contaminant degradation. However, the activation of H2O2 to generate reactive oxygen species is always accompanied by O2 generation resulting in H2O2 waste. Here, we prepare a Ti doped Mn3O4/Fe3O4 ternary catalyst (Ti-Mn3O4/Fe3O4) to create abundant oxygen vacancies (OVs), which yields electron delocalization impacts on enhancing the electrical conductivity, accelerating the activation of O2 to produce H2O2. In Ti-Mn3O4/Fe3O4/H2O2 system, OVs-mediated O2/O2•-/H2O2 redox cycles trigger the activation of locally generated O2, boost the regeneration of O2•- and on site produce H2O2 for replenishment. This leads to a 100% removal of tiamulin in 30 min at an unprecedented H2O2 utilization efficiency of 96.0%, which is 24 folds higher than that with Fe3O4/H2O2. Importantly, further integration of Ti-Mn3O4/Fe3O4 catalysts into membrane filtration achieved high rejections of tiamulin (> 83.9%) from real surface water during a continuous 12-h operation, demonstrating broad pH adaptability, excellent catalytic stability and leaching resistance. This work demonstrates a feasible strategy for developing OVs-rich catalysts for improving H2O2 utilization efficiency via activation of locally generated oxygen during the Haber-Weiss reaction.


Assuntos
Peróxido de Hidrogênio , Oxigênio , Oxirredução , Oxidantes , Catálise
5.
Medicine (Baltimore) ; 102(4): e32757, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36705378

RESUMO

Oocyte matched follicular fluid oxidant, antioxidant status, and pro- and anti-inflammatory cytokine levels were assessed to reveal a possible effect of local-intrafollicular levels of these markers on the individual oocyte with its quality, ability to achieve fertilization, further embryo development, and pregnancy. A cross-sectional study of infertile women with diminished ovarian reserve undergoing antagonist protocol in vitro fertilization (IVF); in the form of ICSI, and fresh single embryo transfer were included. When follicular fluid was collected, each ovarian follicle was aspirated independently, and each follicular fluid was collected into a separate test tube to match it with a single cumulus-oocyte complex obtained from the same follicle. Oocyte matched follicular fluid samples and blood specimens were taken from the participants. Relationships of total antioxidant status, total oxidant status, oxidative stress index, total thiol, interleukin (IL)-6, IL-8, and IL-10 levels of each follicle with oocyte grade, grade of transferred embryos, and pregnancy rate of a given follicle were assessed. A total of 23 infertile women with diminished ovarian reserve and 79 individual follicles of these women were assessed. Serum total oxidant status level of metaphase II (MII) group was significantly lower than non-MII group (P < .001). Follicular fluid IL-6 level of MII group was significantly lower than non-MII group (P = .005). Follicular fluid IL-8 value was significantly low with positive pregnancy results (P < .001). Serum oxidative stress status and follicular fluid pro-inflammatory cytokines were associated with IVF outcomes. This unique study might guide IVF practice with the aim of developing and establishing more effective therapeutic strategies and choosing embryos with more potential for success.


Assuntos
Infertilidade Feminina , Reserva Ovariana , Gravidez , Humanos , Feminino , Líquido Folicular , Antioxidantes , Infertilidade Feminina/terapia , Oxidantes , Citocinas , Estudos Transversais , Interleucina-8 , Oócitos , Fertilização In Vitro/métodos
6.
Dalton Trans ; 52(4): 1062-1073, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36602242

RESUMO

Two mononuclear nonheme iron(II)-benzoylformate (BF) complexes [(6Me2-Me-BPA)Fe(BF)](ClO4) (1a) and [(6Me3-TPMM)Fe(BF)](ClO4) (1b) of tridentate nitrogen donor ligands, bis((6-methylpyridin-2-yl)methyl)(N-methyl)amine (6Me2-Me-BPA) and tris(2-(6-methyl)pyridyl)methoxymethane (6Me3-TPMM), were isolated and characterized. The structural characterization of iron(II)-chloro complexes indicates that the ligand 6Me2-Me-BPA binds to the iron(II) centre in a meridional fashion, whereas 6Me3-TPMM behaves as a facial ligand. Both the ligands were functionalized with terminal thiol for immobilization on gold nanoparticles (AuNPs), and the corresponding iron(II) complexes [(6Me2-BPASH)Fe(BF)(ClO4)]@C8Au (2a) and [(6Me3-TPMSH)Fe(BF)(ClO4)]@C8Au (2b) were prepared to probe the effect of immobilization on their ability to perform bioinspired oxidation reactions. All the complexes react with dioxygen to display the oxidative decarboxylation of the coordinated benzoylformate, but the complexes supported by 6Me3-TPMM and its thiol-appended ligand display faster reactivity compared to their analogues with the 6Me2-Me-BPA-derived ligands. In each case, an electrophilic iron-oxygen oxidant was intercepted as the active oxidant generated from dioxygen. The immobilized complexes (2a and 2b) display enhanced O2-dependent reactivity in oxygen-atom transfer reactions (OAT) and hydrogen-atom transfer (HAT) reactions compared to their homogeneous congeners (1a and 1b). Furthermore, the immobilized complex 2b displays catalytic OAT reactions. This study supports that the ligand geometry and immobilization on AuNPs influence the dioxygen-dependent reactivity of the complexes.


Assuntos
Ferro , Nanopartículas Metálicas , Ferro/química , Ouro , Ligantes , Oxigênio/química , Cetoácidos , Oxidantes , Compostos Ferrosos/química
7.
Int J Mol Sci ; 24(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36674650

RESUMO

The current study evaluates the role of reactive oxygen species (ROS) in bioeffects of magnetite nanoparticles (MNPs), such as bare (Fe3O4), humic acids (Fe3O4-HA), and 3-aminopropyltriethoxysilane (Fe3O4-APTES) modified MNPs. Mössbauer spectroscopy was used to identify the local surrounding for Fe atom/ions and the depth of modification for MNPs. It was found that the Fe3O4-HA MNPs contain the smallest, whereas the Fe3O4-APTES MNPs contain the largest amount of Fe2+ ions. Bioluminescent cellular and enzymatic assays were applied to monitor the toxicity and anti-(pro-)oxidant activity of MNPs. The contents of ROS were determined by a chemiluminescence luminol assay evaluating the correlations with toxicity/anti-(pro-)oxidant coefficients. Toxic effects of modified MNPs were found at higher concentrations (>10-2 g/L); they were related to ROS storage in bacterial suspensions. MNPs stimulated ROS production by the bacteria in a wide concentration range (10-15-1 g/L). Under the conditions of model oxidative stress and higher concentrations of MNPs (>10-4 g/L), the bacterial bioassay revealed prooxidant activity of all three MNP types, with corresponding decay of ROS content. Bioluminescence enzymatic assay did not show any sensitivity to MNPs, with negligible change in ROS content. The results clearly indicate that cell-membrane processes are responsible for the bioeffects and bacterial ROS generation, confirming the ferroptosis phenomenon based on iron-initiated cell-membrane lipid peroxidation.


Assuntos
Nanopartículas de Magnetita , Espécies Reativas de Oxigênio , Nanopartículas de Magnetita/toxicidade , Nanopartículas de Magnetita/química , Bactérias , Oxidantes
8.
Chemosphere ; 313: 137590, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36535505

RESUMO

The electrochemical degradation of air pollutants, particularly volatile organic compounds (VOCs), at their gaseous state is a promising method. However, it remains at an infant stage due to sluggish solid-gas electron transfers at room temperature. We established a triphase reaction condition using a semi-solid electrolyte layer between the electrode and membrane to enhance the electron transfer at room temperature. A polyvinyl alcohol (PVA) gel layer was inserted between a bimetallic layered CuNi(CN)4 complex coated Cu foam electrode (TCNi-Cu) and Nafion 324 membrane for the degradation of gaseous toluene. The cyclic voltammetry of TCNi-Cu using a sodium hydroxide-coated copper mesh electrode at a triphase showed Cu1+ and Ni1+ stabilization at -0.7 and -0.9 V, respectively, which was similar to the liquid phase electron transfer behavior. The degradation capacity of gaseous toluene without using electrogenerated TCNi-Cu + PVA gel was 0.54 mg cm2 min-1, whereas that of TCNi-Cu + PVA gel layers was 1.17 mg cm-2min-1, which revealed the mediation effect at a triphase condition. Toluene was converted into oxygen-containing products, such as butanol, propanol, and acetone (without reduction products), which revealed that indirect oxidation occurred at the cathode using an in-situ generated oxidant, such as OH˙ radical. As an electron-mediator, Cu1+ was used to form oxidants for the degradation of toluene at -0.7 V. The toluene removal rate reached 1.4 µmol h-1, with an energy efficiency of 0.15 Wh L-1. This study is the first attempt to describe a liquid-electrolyte-free cathodic half-cell in electrochemical application to VOCs degradation, highlighting the electron transfer at room temperature.


Assuntos
Poluentes Atmosféricos , Gases , Humanos , Tolueno/química , Elétrons , Poluentes Atmosféricos/análise , Oxirredução , Oxidantes
9.
Vet Parasitol ; 314: 109855, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36528965

RESUMO

Bovine anaplasmosis is an arthropod-borne disease characterized by high fever, anaemia and sometimes jaundice. The role of oxidative stress in anaplasmosis has been investigated, but erythrocyte arginase (ARG) activity has not been studied. In this study, we aimed to investigate the changes in haematological parameters, erythrocyte ARG activity, plasma nitric oxide (NO) levels and oxidative stress parameters and explain the relationship between each other in cattle with anaplasmosis. The material of this study consisted of 14 cattle, aged 10-12 months with anaplasmosis (infected group) and 14 healthy cattle aged 10-12 months (control group). Our data revealed that leukocyte parameters and plasma NO levels and serum malondialdehyde (MDA), total oxidant status (TOS) and oxidative stress index (OSI) levels were higher while erythrocyte parameters, erythrocyte ARG activity and serum total antioxidant status (TAS) and glutathione (GSH) levels were lower in the infected group compared to the control group. There was a strong correlation between erythrocyte ARG activity and NO, MDA, TOS, OSI, TAS and GSH. ROC analysis and correlation results suggest that erythrocyte ARG activity is an effective oxidative stress marker. We concluded that severe oxidative stress occurs in anaplasmosis. As the severity of anaemia increases, erythrocyte ARG activity plummets while plasma NO level elevates. These two parameters may also be used as prognostic and oxidative stress markers. Although decreased erythrocyte ARG activity is a disadvantage in haemolytic diseases, this situation can be compensated by increased NO. Thus, homeostasis of these two parameters may contribute to the elimination of the infection.


Assuntos
Anaplasmose , Anemia , Doenças dos Bovinos , Bovinos , Animais , Óxido Nítrico , Arginase , Estresse Oxidativo , Antioxidantes/metabolismo , Eritrócitos , Oxidantes , Glutationa , Anemia/veterinária
10.
J Colloid Interface Sci ; 634: 231-242, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36535161

RESUMO

Lower reaction speed and excessive oxidant inputs impede the removal of contaminants from water via the advanced oxidation processes based on peroxymonosulfate. Herein, we report a new confined catalysis paradigm via the hollow hetero-shell structured CN@C (H-CN@C), which permits effective decontamination through polymerization with faster reaction rates and lower oxidant dosage. The confined space structures regulated the CN and CO and electron density of the inner shell, which increased the electron transfer rate and mass transfer rate. As a result, CN in H-CN@C-10 reacted with peroxymonosulfate in preference to CO to generate singlet oxygen, improving the second-order reaction kinetics by 503 times. The identification of oxidation products implied that bisphenol AF could effectively remove by polymerization, which could reduce carbon dioxide emissions. These favorable properties make the nanoconfined catalytic polymerization of contaminants a remarkably promising nanocatalytic water purification technology.


Assuntos
Peróxidos , Purificação da Água , Polimerização , Peróxidos/química , Oxidantes
11.
Behav Brain Res ; 438: 114156, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36243244

RESUMO

There are growing evidence indicating that the adolescent brain is persistently affected by the use of psychostimulant agents. In this regard, alcohol drinking has become rather common among the adolescents in many societies during the last decade. It is currently well known that long-term ethanol exposure deteriorates various cognitive functions such as learning and memory. Mechanistically, these adverse effects have been shown to be mediated by oxidative damage to central nervous system. On the other hand, Vit-B12 is known to improve cognitive performance by suppression of oxidative parameters. Thus, in the present study we aimed to test whether treatment by Vit-B12 could prevent ethanol-induced complications in mice using behavioral and biochemical methods. Different groups of male Syrian mice received ethanol, ethanol+Vit-B12, Vit-B12 alone, or saline during adolescence and then learning and memory functions were assessed by Morris water maze (MWM) and Passive Avoidance (PA) tests. Finally, mice were sacrificed for measurement of biochemical factors. Results indicated that, adolescent ethanol intake impairs learning and memory function through exacerbation of oxidative stress and Vit-B12 treatment improves these complications by re-establishment of oxidant/anti-oxidant balance in CNS. Moreover, we found that Vit-B12 prevents ethanol-induced reduction of BDNF and enhancement of GFAP and acetylcholinesterase (AChE) activity. In conclusion, it seems that Vit-B12 supplementation could be used as an effective therapeutic strategy to prevent learning and memory defects induced by chronic alcohol intake during adolescence.


Assuntos
Antioxidantes , Fator Neurotrófico Derivado do Encéfalo , Proteína Glial Fibrilar Ácida , Transtornos da Memória , Animais , Masculino , Camundongos , Acetilcolinesterase , Encéfalo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Etanol/efeitos adversos , Aprendizagem em Labirinto , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/prevenção & controle , Oxidantes , Estresse Oxidativo , Vitamina B 12/farmacologia , Vitamina B 12/uso terapêutico , Proteína Glial Fibrilar Ácida/metabolismo
12.
J Environ Sci (China) ; 123: 350-366, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36521998

RESUMO

Atmospheric oxidizing capacity (AOC) is an essential driving force of troposphere chemistry and self-cleaning, but the definition of AOC and its quantitative representation remain uncertain. Driven by national demand for air pollution control in recent years, Chinese scholars have carried out studies on theories of atmospheric chemistry and have made considerable progress in AOC research. This paper will give a brief review of these developments. First, AOC indexes were established that represent apparent atmospheric oxidizing ability (AOIe) and potential atmospheric oxidizing ability (AOIp) based on aspects of macrothermodynamics and microdynamics, respectively. A closed study refined the quantitative contributions of heterogeneous chemistry to AOC in Beijing, and these AOC methods were further applied in Beijing-Tianjin-Hebei and key areas across the country. In addition, the detection of ground or vertical profiles for atmospheric OH·, HO2·, NO3· radicals and reservoir molecules can now be obtained with domestic instruments in diverse environments. Moreover, laboratory smoke chamber simulations revealed heterogeneous processes involving reactions of O3 and NO2, which are typical oxidants in the surface/interface atmosphere, and the evolutionary and budgetary implications of atmospheric oxidants reacting under multispecies, multiphase and multi-interface conditions were obtained. Finally, based on the GRAPES-CUACE adjoint model improved by Chinese scholars, simulations of key substances affecting atmospheric oxidation and secondary organic and inorganic aerosol formation have been optimized. Normalized numerical simulations of AOIe and AOIp were performed, and regional coordination of AOC was adjusted. An optimized plan for controlling O3 and PM2.5 was analyzed by scenario simulation.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluição do Ar/análise , Atmosfera/química , Aerossóis/análise , Oxirredução , Oxidantes , Poluentes Atmosféricos/análise , Material Particulado/análise , China , Monitoramento Ambiental
13.
J Environ Sci (China) ; 127: 615-627, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36522091

RESUMO

Natural siderite (FeCO3), simulated synthetic siderite and nZVI/FeCO3 composite were used as green and easily available iron-based catalysts in peroxydisulfate activation for remediating 2-chlorophenol as the target contaminant and this technique can effectively degrade organic pollutants in the soil. The key reaction parameters such as catalysts dosage, oxidant concentration and pH, were investigated to evaluate the catalytic performance of different materials in catalytic systems. The buffering property of natural soil conduced satisfactory degradation performance in a wide pH range (3-10). Both the main non-radical of 1O2 and free radicals of SO4·- and OH· were evidenced by quenching experiment and electron paramagnetic resonance. The reduction of nZVI on FFC surface not only has the advantage for electronic transfer to promote the circulation of Fe(III) to Fe(II), but also can directly dechlorinate. Furthermore, the intermediates were comprehensively analyzed by GC-MS and a potential removal mechanism of three oxidant system for 2-CP soil degradation was obtained. Briefly, this research provides a new perspective for organic contaminate soil treatment using natural siderite or simulated synthetic siderite as efficient and environmental catalytic material.


Assuntos
Compostos Férricos , Poluentes Químicos da Água , Compostos Férricos/química , Solo , Carbonatos/química , Oxirredução , Oxidantes , Poluentes Químicos da Água/análise
14.
ACS Chem Biol ; 18(1): 112-122, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36543757

RESUMO

Chemical proteomics is a powerful technology that can be used in the studies of the functions of uncharacterized proteins in the human proteome. It relies on a suitable bioconjugation strategy for protein labeling. This could be either a UV-responsive photo-crosslinker or an electrophilic warhead embedded in chemical probes that can form covalent bonds with target proteins. Here, we report a new protein-labeling strategy in which a nitrile oxide, a highly reactive intermediate that reacts with proteins, can be efficiently generated by the treatment of oximes with a water-soluble and a minimally toxic oxidant, phenyliodine bis (trifluoroacetate) (PIFA). The resulting intermediate can rapidly bioconjugate with amino acid residues of target proteins, thus enabling target identification of oxime-containing bioactive molecules. Excellent chemoselectivity of cysteine residues by the nitrile oxide was observed, and over 4000 reactive and/or accessible cysteines, including KRAS G12C, have been successfully characterized by quantitative chemical proteomics. Some of these residues could not be detected by conventional cysteine reagents, thus demonstrating the complementary utility of this method.


Assuntos
Cisteína , Oxidantes , Humanos , Cisteína/química , Indicadores e Reagentes , Proteoma/química , Óxidos
15.
Addict Biol ; 28(1): e13254, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36577724

RESUMO

Recently, it has been suggested that central and peripheral toxicities identified in persons with substance use disorder (SUD) could be partially associated with an imbalance in reactive oxygen species and antioxidant defenses. We conducted a systematic review and meta-analysis to investigate whether SUD is associated with oxidative stress and to identify biomarkers possibly more affected by this condition. We have included studies that analysed oxidant and antioxidant markers in individuals with SUD caused by stimulants, alcohol, nicotine, opioids, and others (cannabis, inhalants, and polysubstance use). Our analysis showed that persons with SUD show higher oxidant markers and lower antioxidant markers than healthy controls. SUD was associated specifically with higher levels of oxidant markers malondialdehyde, thiobarbituric acid reactive substances and lipid peroxidation. Conversely, the antioxidant superoxide dismutase and the total antioxidant capacity/status were lowered in the SUD group. A meta-regression analysis revealed that persons with alcohol use disorder had higher oxidative stress estimates than those with stimulant use disorder. Moreover, individuals evaluated during abstinence showed smaller antioxidant effect sizes than non-abstinent ones. Our findings suggest a clear oxidative imbalance in persons with SUD, which could lead to cell damage and result in multiple associated comorbidities, particularly accelerated aging.


Assuntos
Antioxidantes , Transtornos Relacionados ao Uso de Substâncias , Humanos , Estresse Oxidativo , Substâncias Reativas com Ácido Tiobarbitúrico , Oxidantes
16.
Toxicon ; 222: 106993, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36528210

RESUMO

Melittin (MLT) treatment is believed to enhance tumor cell death, apoptotic, and oxidative cytotoxic effects of cisplatin (CSP) via the modulation of Ca2+ channels in several cancer lines. The activation of TRPM2 mediated anticancer and CSP resistance actions via mitochondrial Ca2+ and Zn2+ accumulation-induced mitochondrial reactive free oxygen species (MitSOX) in the glioblastoma cells. The aim was to elucidate the effects of CSP and MLT combination via the TRPM2 stimulation on the tumor cell viability, cell number, cell death (propidium iodide/Hoechst rate), apoptosis, and MitSOX levels in the DBTRG-05MG cells. In the DBTRG-05MG cells, we induced four groups as control, MLT (2.5 µg/ml for 24 h), CSP (25 µM for 24 h), and CSP + MLT. The CSP-induced intracellular Ca2+ influxes to the TRPM2 activation were increased in the cells from coming H2O2 and ADP-Ribose. The influxes were decreased in the cells by the incubations of TRPM2 antagonists (ACA and carvacrol). The incubation of CSP increased the parameters of intracellular Ca2+ responses, mitochondria function, cytosolic free Zn2+ accumulation, apoptosis (caspase -3, -8, and -9), and MitSOX generation in the tumor cells. After the treatment of MLT with/without CSP, the parameters were further increased in the cells. In conclusion, the treatment of MLT increased the anticancer, tumor cell death, apoptotic, and oxidant effects of CSP in the glioblastoma tumor cells via activating the TRPM2. As a result, TRPM2 stimulation by MLT may be utilized as a successful agent in the CSP treatment of glioblastoma tumors.


Assuntos
Venenos de Abelha , Glioblastoma , Canais de Cátion TRPM , Humanos , Cisplatino/farmacologia , Cisplatino/metabolismo , Glioblastoma/tratamento farmacológico , Estresse Oxidativo , Meliteno/farmacologia , Canais de Cátion TRPM/metabolismo , Venenos de Abelha/farmacologia , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Apoptose , Oxidantes/farmacologia , Cálcio/metabolismo
17.
J Org Chem ; 88(1): 60-74, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36563107

RESUMO

Presented herein is a controllable selective construction of spiro or fused heterocyclic scaffolds through the one-pot cascade reactions of 1-phenylpyrazolidinones with maleimides. To be specific, succinimide spiro pyrazolo[1,2-a]pyrazolones were effectively formed via [4 + 1] spiroannulation of 1-phenylpyrazolidinones with maleimides through simultaneous C(sp2)-H bond activation/functionalization and intramolecular cyclization along with the traceless fusion of the pyrazolidinonyl unit into the final product. In this reaction, air acts as a cost-effective and environmentally sustainable oxidant to assist the regeneration of the Rh(III) catalyst. Alternatively, succinimide-fused pyrazolidinonylcinnolines were formed from the same starting materials through an initial [4 + 1] spiroannulation followed by base-promoted skeleton rearrangement of the in situ formed spiro product without isolation. Notable features of these protocols include easily tunable selectivity, broad substrate scope, cost-effective and sustainable oxidant, excellent atom economy, and facile scalability.


Assuntos
Oxidantes , Pirazolonas , Maleimidas/química , Estrutura Molecular , Succinimidas
18.
J Hazard Mater ; 443(Pt A): 130192, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36270191

RESUMO

While extensive works focused on the enhancement of the activity of heterogeneous Fenton catalysts, little was paid attention to the inhibition of soil organic matter (SOM) and Mn minerals in soil remediation. Here, the oxidation of petroleum hydrocarbons in soils (S1: 4.28 % SOM, S2: 6.04 % SOM, S3: 10.33 % SOM) with inactivated SOM and passivated Mn oxides regulating by calcium superphosphate (Ca(H2PO4)2) was carried out. Oily sludge pyrolysis residue was used as precursors to prepare an oleophilic iron-supported solid catalyst (Fe-N @ PR). For regulated systems, under the optimal conditions of 1.8 mmol/g H2O2 and 0.05 g/g Fe-N @ PR, 72 ∼ 91 % of total petroleum hydrocarbons (TPHs: 15,616.58 mg/kg) were oxidized, which was 38 ∼ 45 % higher than that of control systems. The mechanism of efficient oxidation was proposed that the passivated Mn minerals stabilized H2O2 redistributing more H2O2 to sustainably produce •OH, and the inactivated SOM improved the relative reactivity of •OH to TPHs. Additionally, the passivation of Mn oxides was mainly related to the binding of H2PO4-, and the inactivation of SOM was realized by Ca2+ combing with -OH and C-O-C to form stable complexes. This study brought us a new perspective on soil remediation through passivating Mn minerals and inactivating SOM.


Assuntos
Petróleo , Poluentes do Solo , Solo/química , Manganês , Poluentes do Solo/análise , Oxidantes , Peróxido de Hidrogênio/química , Hidrocarbonetos , Oxirredução , Minerais , Óxidos
19.
Org Biomol Chem ; 21(2): 300-305, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36514892

RESUMO

Here, we developed an air-stable, earth-abundant cobalt(III)-catalyzed regioselective mono-olefination of arenes directed by urea under mild conditions through a cross-dehydrogenative coupling (CDC) process. Under the optimized conditions, a high regioselectivity of mono-olefination was achieved with various electron-rich and electron-deficient arenes, which afforded E-alkenylated products (with yields of up to 90%). In contrast to the conditions used for noble-metal-catalyzed olefination directed by weakly coordinating groups, our reaction was operated under mild conditions, including mild temperature (40 °C) and non-metallic oxidant.


Assuntos
Alcenos , Cobalto , Catálise , Estrutura Molecular , Oxidantes
20.
Dalton Trans ; 52(3): 540-545, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36537082

RESUMO

Cu(II) complexes supported by tetradentate amido-quinoline acyclic ligands (L1 & L2) have been synthesized, characterized, and employed as catalysts for aromatic C-H hydroxylation using H2O2 as an oxidant in the absence of an external base with a high selectivity of around 90% for phenols via the non-radical pathway (TON ≥720). The KIE value, various spectroscopic studies and DFT calculation supported the involvement of Cu(II)-OOH species.


Assuntos
Peróxido de Hidrogênio , Quinolinas , Peróxido de Hidrogênio/química , Modelos Moleculares , Hidroxilação , Oxidantes/química , Ligantes
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