The inhibitory effect of the methanolic extract of the root of Aegle marmelos (MERA) and its constituents on the lipid peroxidation in vivo and in vitro were studied. The results suggested that MERA increased the acti...The inhibitory effect of the methanolic extract of the root of Aegle marmelos (MERA) and its constituents on the lipid peroxidation in vivo and in vitro were studied. The results suggested that MERA increased the activities of superoxide dismutase (SOD) and GSH-peroxidase in the liver cytosol of mice, but showed no significant effect on the activity of catalase, and one of its major constituents, 4-methoxy-1-methyl-2-quinolone (MMQ) increased the activity of SOD in liver tissue of mice intoxicated with FeCl2-ascorbic acid (AA)-ADP in vivo. Various constituents isolated from the root of title plant inhibited the lipid peroxidation in rat liver homogenate, which was in vitro induced by FeCl2-ascorbic acid, CCl4-NADPH, or ADP- NADPH. Of the test compounds, MMQ and its derivatives integriquinolone were similar to (-tocopherol in inhibiting MDA production in rat liver microsomes induced by Fe2+-ascorbate, CCl4-NADPH, or ADP-NADPH.展开更多
This study evaluated the mechanisms of 5-fluorouracil (5-FU) induced intestinal damage by investi-gating the lipid peroxide (LPO) level, myeloperoxidase (MPO) activity and disaccharidase activity in rats.Group Ⅰ anim...This study evaluated the mechanisms of 5-fluorouracil (5-FU) induced intestinal damage by investi-gating the lipid peroxide (LPO) level, myeloperoxidase (MPO) activity and disaccharidase activity in rats.Group Ⅰ animals (n=6) were sacrificed and served as a normal control group. Group Ⅱ animaIes (n= 24 )were given a single intraperitoneal injection of 5-FU (150 mg/kg) and every 8 rats were sacrificed on day1,3 and 5 after injection respectively. Results: LPO concentration in blood and intestinal mucosa was sig-nificantly higher in the group Ⅱ than in the group Ⅰ on day 1 and 3 (P<0. 05) MPO activity was signif-icantly higher in the group I than in the group Ⅰ at different times (P<0. 01 ). Lactase activity on day 5(P<0. 01); sucrase activity (P<0. 01 and P<0. 05 respectiviely) and maltase activity (P<0. 01 ) on day3 and 5, were significantly lower in the group than in the group l. Conclusion: The results indicatethat neutrophil infiltration may be involved in 5-FU-induced lipid peroxidative damage of the small intes-tine which was reflected by the decreased disaccharidases activities.展开更多
BACKGROUND Ulcerative colitis(UC)is a chronic and debilitating inflammatory bowel disease.Cumulative evidence indicates that excess hydrogen peroxide,a potent neutrophilic chemotactic agent,produced by colonic epithel...BACKGROUND Ulcerative colitis(UC)is a chronic and debilitating inflammatory bowel disease.Cumulative evidence indicates that excess hydrogen peroxide,a potent neutrophilic chemotactic agent,produced by colonic epithelial cells has a causal role leading to infiltration of neutrophils into the colonic mucosa and subsequent development of UC.This evidence-based mechanism identifies hydrogen peroxide as a therapeutic target for reducing agents in the treatment of UC.CASE SUMMARY Presented is a 41-year-old female with a 26-year history of refractory UC.Having developed steroid dependence and never achieving complete remission on treatment by conventional and advanced therapies,she began treatment with oral R-dihydrolipoic acid(RDLA),a lipid-soluble reducing agent with intracellular site of action.Within a week,rectal bleeding ceased.She was asymptomatic for three years until a highly stressful experience,when she noticed blood in her stool.RDLA was discontinued,and she began treatment with oral sodium thiosulfate pentahydrate(STS),a reducing agent with extracellular site of action.After a week,rectal bleeding ceased,and she resumed oral RDLA and discontinued STS.To date,she remains asymptomatic with normal stool calprotectin while on RDLA.CONCLUSION STS and RDLA are reducing agents that serve as highly effective and safe therapy for the induction and maintenance of remission in UC,even in patients refractory or poorly controlled by conventional and advanced therapies.Should preliminary findings be validated by subsequent clinical trials,the use of reducing agents could potentially prevent thousands of colectomies and represent a paradigm shift in the treatment of UC.展开更多
Objective： To study the intervention effects of Jianpi Liqi Huoxue Decoction （健脾理气活血汤, JLHD） on lipid peroxidative liver injury induced by alcohol. Methods： The rat alcoholic model of liver disease （ALD） ...Objective： To study the intervention effects of Jianpi Liqi Huoxue Decoction （健脾理气活血汤, JLHD） on lipid peroxidative liver injury induced by alcohol. Methods： The rat alcoholic model of liver disease （ALD） induced by Lieber-DeCarli liquid diet was established. Thirty-two male SD rats were randomly divided into 4 groups ： the normal group （ n = 5）, the control group （ n = 9）, the model group （ n = 9） and the JLHD group （ n =9）. From the 4th week after modeling, the rats were given JLHD or distilled water by gastrogavage respectively, and the samples of blood and liver tissues were taken out from the rats for determination by the end of the 8th week. The hepatic pathological changes were observed with HE staining; the liver injury related indices, including activity of alanine aminotransferase （ALT） and aspartate aminotransferase （AST） in serum, γ-glutamyl transpeptidase （γ-GT） activity and triglyceride （TG） content in liver tissues, as well as the lipid peroxidation related indices, including malonaldehyde （MDA） content and nitric oxide synthase （NOS） activity in liver tissue, serum Fe^2＋ level, and the anti-peroxidation capacity related indices, including superoxide dismutase （SOD） activity, glutathion （GSH） content and reactive oxygen species （anti- ROS） activity in liver tissues were determined. Results： （ 1 ） There were obvious figures of fatty degeneration and inflammatory infiltration in liver tissues of the model group. As compared with the control group, in the model group, the activity of ALT and AST, and Fe^2＋ content in serum, γ-GT and NOS activity, TG and MDA content in liver tissues were significantly higher （ P〈0. 01 ）, while the activity of SOD, GSH and anti-ROS in liver tissues were significantly lower （P〈0.01）. （2） The fatty degeneration and inflammatory infiltration of liver tissues in the JLHD group were significantly lessen as compared with those in the model group; and the abnormalities of all the indexes revealed in the model rats were restored to certain extent in the JLHD group, and especially significant were the levels of ALT activity, MDA content and Fe^2＋ , which were nearly normal. Conclusion： JLHD has significant effects against alcoholic liver injury, the acting mechanism of which is likely to be related with its anti-lipid peroxidative effect.展开更多
Alzheimer's disease is an age-related neurodegenerative disorder with a complex and incompletely understood pathogenesis. Despite extensive research, a cure for Alzheimer's disease has not yet been found. Oxid...Alzheimer's disease is an age-related neurodegenerative disorder with a complex and incompletely understood pathogenesis. Despite extensive research, a cure for Alzheimer's disease has not yet been found. Oxidative stress mediates excessive oxidative responses, and its involvement in Alzheimer's disease pathogenesis as a primary or secondary pathological event is widely accepted. As a member of the selenium-containing antioxidant enzyme family, glutathione peroxidase 4 reduces esterified phospholipid hydroperoxides to maintain cellular redox homeostasis. With the discovery of ferroptosis, the central role of glutathione peroxidase 4 in anti-lipid peroxidation in several diseases, including Alzheimer's disease, has received widespread attention. Increasing evidence suggests that glutathione peroxidase 4 expression is inhibited in the Alzheimer's disease brain, resulting in oxidative stress, inflammation, ferroptosis, and apoptosis, which are closely associated with pathological damage in Alzheimer's disease. Several therapeutic approaches, such as small molecule drugs, natural plant products, and non-pharmacological treatments, ameliorate pathological damage and cognitive function in Alzheimer's disease by promoting glutathione peroxidase 4 expression and enhancing glutathione peroxidase 4 activity. Therefore, glutathione peroxidase 4 upregulation may be a promising strategy for the treatment of Alzheimer's disease. This review provides an overview of the gene structure, biological functions, and regulatory mechanisms of glutathione peroxidase 4, a discussion on the important role of glutathione peroxidase 4 in pathological events closely related to Alzheimer's disease, and a summary of the advances in small-molecule drugs, natural plant products, and non-pharmacological therapies targeting glutathione peroxidase 4 for the treatment of Alzheimer's disease. Most prior studies on this subject used animal models, and relevant clinical studies are lacking. Future clinical trials are required to validate the therapeutic effects of strategies targeting glutathione peroxidase 4 in the treatment of Alzheimer's disease.展开更多
Ulcerative colitis has baffled researchers since the early 20th century.The pre-vailing explanation attributes the chronic recurring episodes of bloody diarrhea and abdominal pain to some form of immune abnormality,de...Ulcerative colitis has baffled researchers since the early 20th century.The pre-vailing explanation attributes the chronic recurring episodes of bloody diarrhea and abdominal pain to some form of immune abnormality,despite the lack of supporting evidence.This highlights the critical need for innovative research directions and methodologies to uncover the cause and develop a cure for this disease.By analyzing existing data from less than a dozen previously published studies,a novel,evidence-based pathogenesis was constructed,implicating colonic epithelial hydrogen peroxide as a causal factor in the development of this disease.This newly identified mechanism informed the creation of a ground-breaking class of therapeutics,known as reducing agents,which have demon-strated remarkable success in resolving colonic inflammation and restoring colonic health in patients with refractory ulcerative colitis.This paper outlines the timeline of these publications and reinterprets the findings within the context of contemporary biomedical science.展开更多
Ferroptosis,a type of programmed cell death,represents a distinct paradigm in cell biology.It is characterized by the iron-dependent accumulation of reactive oxygen species,which induce lipid peroxidation(LPO),and is ...Ferroptosis,a type of programmed cell death,represents a distinct paradigm in cell biology.It is characterized by the iron-dependent accumulation of reactive oxygen species,which induce lipid peroxidation(LPO),and is orchestrated by the interplay between iron,lipid peroxides,and glutathione.In this review,we emphasize the frequently overlooked role of iron in LPO beyond the classical iron-driven Fenton reaction in several crucial processes that regulate cellular iron homeostasis,including iron intake and export as well as ferritinophagy,and the emerging roles of endoplasmic reticulum-resident flavoprotein oxidoreductases,especially P450 oxidoreductases,in modulating LPO.We summarize how various types of fatty acids(FAs),including saturated,monounsaturated,and polyunsaturated FAs,differentially influence ferroptosis when incorporated into phospholipids.Furthermore,we highlight the therapeutic potential of targeting LPO to mitigate ferroptosis and discuss the regulatory mechanisms of endogenous lipophilic radical-trapping antioxidants that confer resistance to ferroptosis,shedding light on therapeutic avenues for ferroptosis-associated diseases.展开更多
Gastric Carcinoma(GC)is a highly fatal malignant tumor with a poor prognosis.Its elevated mortality rates are primarily due to its proclivity for late-stage metastasis.Exploring the metabolic interactions between tumo...Gastric Carcinoma(GC)is a highly fatal malignant tumor with a poor prognosis.Its elevated mortality rates are primarily due to its proclivity for late-stage metastasis.Exploring the metabolic interactions between tumor microenvironment and the systemic bloodstream could help to clearly understand the mechanisms and identify precise biomarkers of tumor growth,proliferation,and metastasis.In this study,an integrative approach that combines plasma metabolomics with mass spectrometry imaging of tumor tissue was developed to investigate the global metabolic landscape of GC tumorigenesis and metastasis.The results showed that the oxidized glutathione to glutathione ratio(GSSH/GSH)became increased in non-distal metastatic GC(M0),which means an accumulation of oxidative stress in tumor tissues.Furthermore,it was found that the peroxidation of polyunsaturated fatty acids,such as 9,10-EpOMe,9-HOTrE,etc.,were accelerated in both plasma and tumor tissues of distal metastatic GC(M1).These changes were further confirmed the potential effect of CYP2E1 and GGT1 in metastatic potential of GC by mass spectrometry imaging(MSI)and immunohistochemistry(IHC).Collectively,our findings reveal the integrated multidimensional metabolomics approach is a clinical useful method to unravel the bloodtumor metabolic crosstalk,illuminate reprogrammed metabolic networks,and provide reliable circulating biomarkers.展开更多
BACKGROUND Fistula-in-ano is an abnormal tunnel formation linking the anal canal with the perineum and perianal skin.Multiple imagining methods are available to evaluate it,among which magnetic resonance imaging(MRI)i...BACKGROUND Fistula-in-ano is an abnormal tunnel formation linking the anal canal with the perineum and perianal skin.Multiple imagining methods are available to evaluate it,among which magnetic resonance imaging(MRI)is the most advanced nonin-vasive preoperative method.However,it is limited in its visualization function.AIM To investigate the use of intraluminal MRI for perianal fistulas via a novel direct MRI fistulography method.METHODS We mixed 3%hydrogen peroxide(HP)with gadolinium for HPMRI fistulogra-phy,retrospectively analyzing 60 cases of complex/recurrent fistula-in-ano using physical examination,trans-perineal ultrasonography(TPUS),low-spatial-reso-lution MRI,and high-resolution direct HPMRI fistulography.We assessed detec-tion rates of fistula tracks,internal openings,their relationship with anal sphinc-ters,and perianal abscesses using statistical analyses,including interobserver agreement(Kappa statistic),and compared results with intraoperative findings.RESULTS Surgical confirmation in 60 cases showed that high-resolution direct HPMRI fis-tulography provided superior detection rates for internal openings(153)and fistula tracks(162)compared to physical exams,TPUS,and low-spatial-resolution MRI(Z>5.7,P<0.05).The effectiveness of physical examination and TPUS was also inferior to that of our method for detecting perianal abscesses(54)(Z=6.773,3.694,P<0.05),whereas that of low-spatial-resolution MRI was not significantly different(Z=1.851,P=0.06).High-resolution direct HPMRI fistulography also achieved the highest interobserver agreement(Kappa:0.89,0.85,and 0.80),while low-spatial-resolution MRI showed moderate agreement(Kappa:0.78,0.74,and 0.69).TPUS and physical examination had lower agreement(Kappa range:0.33-0.63).CONCLUSION High-resolution direct HPMRI fistulography enhances the visualization of recurrent and complex fistula-in-ano,including branched fistulas,allowing for precise planning and improved surgical outcomes.展开更多
Hydrogen peroxide(H_(2)O_(2))is a crucial,eco-friendly oxidizing agent with a wide range of industrial,environmental,and biomedical applications.Traditional production methods,such as the anthraquinone process,face si...Hydrogen peroxide(H_(2)O_(2))is a crucial,eco-friendly oxidizing agent with a wide range of industrial,environmental,and biomedical applications.Traditional production methods,such as the anthraquinone process,face significant challenges in terms of energy consumption and environmental impact.As a sustainable alternative,photocatalytic H_(2)O_(2) production,driven by solar energy,has emerged as a promising approach.This review discusses the key advancements in photocatalytic H_(2)O_(2) synthesis,focusing on overcoming challenges such as charge recombination,selectivity for the two-electron oxygen reduction reaction(2e^(-)ORR),and catalyst stability.Recent innovations in photocatalyst design,including high-entropy materials,single-atom catalysts,and covalent organic frameworks(COFs),have significantly enhanced efficiency and stability.Furthermore,novel strategies for optimizing charge separation,light harvesting,and mass transfer are explored.The integration of artificial intelligence and bioinspired systems holds potential for accelerating progress in this field.This review provides a comprehensive overview of current challenges and cutting-edge solutions,offering valuable insights for the development of scalable,decentralized H_(2)O_(2) production systems that contribute to a more sustainable future.展开更多
Electrocatalytic hydrogen peroxide(H_(2)O_(2))production via the two-electron oxygen reduction reaction(2e−ORR)is promising,but non-metal catalysts with high selectivity are lacking.Herein,a high content of pyrrolic N...Electrocatalytic hydrogen peroxide(H_(2)O_(2))production via the two-electron oxygen reduction reaction(2e−ORR)is promising,but non-metal catalysts with high selectivity are lacking.Herein,a high content of pyrrolic N doped carbon(HPNC)with small mesopores is constructed.Over 80%H_(2)O_(2) selectivity at a wide potential of 0.2–0.6 V is achieved.The finite element simulation reveals that small pore-size mesopores are beneficial to O_(2) adsorption.And in-situ characterization proves that HPNC suppresses the breakage of Osingle bondO bond and enhances the stabilization of *OOH intermediates,thus improving the 2e−ORR performance.This work highlights the combination of non-metal active sites and geometry for 2e−ORR electrocatalysis.展开更多
Extensive neurodegeneration is a hallmark of traumatic spinal cord injury (SCI) that underlies permanent sensorimotor and autonomic impairments (Alizadeh et al.,2019).Following the primary impact,the spinal cord under...Extensive neurodegeneration is a hallmark of traumatic spinal cord injury (SCI) that underlies permanent sensorimotor and autonomic impairments (Alizadeh et al.,2019).Following the primary impact,the spinal cord undergoes a cascade of secondary injury mechanisms that are driven by disruption of the blood-spinal cord ba rrier,vascula r inju ry,glial reactivity,neu roinfla mmation,oxidative stress,lipid peroxidation,and glutamate excitotoxicity that culminate in neuronal and oligodendroglial cell death,demyelination,and axonal damage(Alizadeh et al.,2019).To achieve a meaningful functional recovery after SCI,regeneration of new neurons and oligodendrocytes and their successful growth and integration within the neural network are critical steps for reconstructing the damaged spinal cord tissue (Fischer et al.,2020).展开更多
Background:Cardiac fibrosis following myocardial infarction(MI)drives adverse ventricular remodeling and heart failure,with cardiac fibroblasts(CFs)playing a central role.Glutathione S-transferase mu 1(GSTM1)is an imp...Background:Cardiac fibrosis following myocardial infarction(MI)drives adverse ventricular remodeling and heart failure,with cardiac fibroblasts(CFs)playing a central role.Glutathione S-transferase mu 1(GSTM1)is an important member of the glutathione S-transferase(GSTs)family,which plays an important role in maintaining cell homeostasis and detoxification.This study investigated the role and mechanism of GSTM1 in post-MI fibrosis.Methods:Multi-omics approaches(proteomics/scRNA-seq)identified GSTM1 as a dysregulated target in post-MI fibroblasts.Using a murine coronary ligation model,we assessed GSTM1 dynamics via molecular profiling,such as Western blotting,immunofluorescence,and real-time quantitative polymerase chain reaction.Adeno-associated virus serotype 9(AAV9)-mediated cardiac-specific GSTM1 overexpression was achieved through systemic delivery.In vitro studies employed transforming growth factor-β(TGF-β)-stimulated primary fibroblasts with siRNA/plasmid interventions.Mechanistic insights were derived from transcriptomics and lipid peroxidation assays.Results:The expression of GSTM1 in mouse CFs after MI was significantly down-regulated at both transcriptional and protein levels.In human dilated cardiomyopathy(DCM)patients with severe heart failure,GSTM1 expression was decreased alongside aggravated fibrosis.Overexpression of GSTM1 in post-MI mice improved cardiac function,while significantly reducing infarct size and fibrosis compared with the control group.In vitro models demonstrated that GSTM1 markedly attenuated collagen secretion and activation of fibroblasts,as well as suppressed their proliferation and migration.Further studies revealed that GSTM1 overexpression significantly inhibited the generation of intracellular and mitochondrial reactive oxygen species(ROS)under pathological conditions,suggesting that GSTM1 exerts an antioxidative stress effect in post-infarction fibroblasts.Further investigation of molecular mechanisms indicated that GSTM1 may suppress the initiation and progression of fibrosis by modulating lipid metabolism and ferroptosis-related pathways.Overexpression of GSTM1 significantly reduced lipid peroxidation and free ferrous iron levels in fibroblasts and mitochondria,markedly decreased ferroptosis-related indicators,and alleviated oxidative lipid levels[such as 12-hydroxyeicosapentaenoic acid(HEPE)and 9-,10-dihydroxy octadecenoic acid(DHOME)]under fibrotic conditions.GSTM1 enhanced the phosphorylation of signal transducer and activator of transcription 3(STAT3),thereby upregulating the downstream expression of glutathione peroxidase 4(GPX4),reducing ROS production,and mitigating fibroblast activation and phenotypic transformation by inhibiting lipid peroxidation.Conclusions:This study identifies GSTM1 as a key inhibitor of fibroblast activation and cardiac fibrosis,highlighting its ability to target ferroptosis through redox regulation.AAV-mediated GSTM1 therapy demonstrates significant therapeutic potential for improving outcomes post-MI.展开更多
Hydrogen peroxide(H_(2)O_(2)),as a green oxidant,plays a vital role in various applications,including environmental remediation,disinfection,and chemical synthesis[1].The conventional anthraquinone process,despite its...Hydrogen peroxide(H_(2)O_(2)),as a green oxidant,plays a vital role in various applications,including environmental remediation,disinfection,and chemical synthesis[1].The conventional anthraquinone process,despite its industrial maturity and high yield,suffers from high energy consumption,carbon emissions,safety risks,and reliance on precious metals[2].Despite ongoing optimizations,a more sustainable alternative is urgently needed.The direct synthesis of hydrogen peroxide from water and oxygen has long been considered as an ideal alternative due to its theoretical 100%atom efficiency and environmental sustainability.展开更多
Ferroptosis, an iron-dependent type of cell death, is being considered for new clinical treatments of malignant tumors that are difficult to treat with apoptosis inducers. Although several reports have attempted to in...Ferroptosis, an iron-dependent type of cell death, is being considered for new clinical treatments of malignant tumors that are difficult to treat with apoptosis inducers. Although several reports have attempted to increase the sensitivity of cells to cell death by combining ferroptosis and apoptosis inducers using a single treatment, detailed elucidation of the respective mechanisms of ferroptosis and apoptosis during cell death remains unclear. Here, we evaluated combined treatment effectiveness using the apoptosis-sensitive rat insulinoma INS-1 cell lines. DNA laddering, an indicator of camptothecin (CPT)-induced apoptosis, was abolished by adding RSL3 and ML-162, but not erastin. We found that when the cells were treated with the apoptosis inducer CPT or the ferroptosis inducer RSL3, respectively, the degree of cytotoxicity observed increased dose-dependently. However, a combined CPT and RSL3 treatment did not show a synergistic decrease in cell viability. Camptothecin did not significantly affect increases in intracellular lipid peroxidation and reactive oxygen species or increases in mitochondrial and cytoplasmic free iron levels that were induced by treatment with RSL3 alone. Moreover, deferoxamine and α-tocopherol were found to inhibit RSL3-induced cytotoxicity but did not protect against CPT or CPT and RSL3-induced cytotoxicity. Finally, the exogenous addition of tert-butyl hydroperoxide inhibited DNA ladder formation that is induced by CPT, while the addition of hydrogen peroxide or ferrous ammonium sulfate had no effect. Taken together, these results suggest that lipid peroxides generated during ferroptosis may suppress cell death induced by apoptotic mechanisms.展开更多
A mesocosm-based study was conducted to assess the effect of glucose and hydrogen peroxide on periphyton communities. These chemicals have been found to be effective at controlling cyanobacteria blooms in the water co...A mesocosm-based study was conducted to assess the effect of glucose and hydrogen peroxide on periphyton communities. These chemicals have been found to be effective at controlling cyanobacteria blooms in the water column but their impact on attached communities is unknown. The experimental design included a total of 4 treatments: control (no chemicals;3 replicates);hydrogen peroxide (3 replicates);glucose alone (3 different concentrations [no replicates]);and additive glucose (3 replicates). After 34 days, mean values of chlorophyll a were lower in all experimental treatments compared to the control;mean AFDM values were lower in all treatments except the unreplicated high glucose alone treatment. In contrast, mean autotrophic index values (AFDM/chlorophyll a) were greater in all treatments compared to the control, indicating heterotrophs were more resistant to the chemical treatments than autotrophs. Periphyton community biodiversity was much lower in the additive glucose and moderate glucose alone treatments than the hydrogen peroxide and control treatments. The relative abundance of the bacteria Asticcacaulis and Sphingorhabdus responded positively to the glucose treatments, whereas relative abundance of Nevskia and Caenimonas declined in both the hydrogen peroxide and glucose treatments. In terms of relative abundance, no cyanobacteria taxa were detected among the top 20 taxa. We conclude that the autotrophic component of periphyton communities is especially vulnerable to hydrogen peroxide and glucose treatments, and that any management strategy employing these chemicals should be aware of this potential impact.展开更多
Pyrrhotite oxidation poses a big threat to water environment duo to its high potential for generating pollutants.Hydrogen peroxide,commonly found in natural water at micromolar concentrations,possesses much more aggre...Pyrrhotite oxidation poses a big threat to water environment duo to its high potential for generating pollutants.Hydrogen peroxide,commonly found in natural water at micromolar concentrations,possesses much more aggressive oxidation ability than oxygen and can complicate the pyrrhotite oxidation process.Here,the effects of micromolar H_(2)O_(2) on the biotic and abiotic oxidation of pyrrhotite were examined at pH 1.93 and 6.45,respectively.Pyrrhotite oxidation was much more severe in acidic solutions compared to near neutral solutions.Jarosite with a high Fe/S molar ratio was widely detected in the precipitate collected in acidic solutions,and the introduction of external H_(2)O_(2) influenced the crystallinity of jarosite.A layer of iron-deficient iron-sulfur oxide formed on the surface of pyrrhotite prevents its continuous oxidation,and the presence of Acidithiobacillus ferrooxidans enhanced this situation by promoting the release of Fe from the pyrrhotite.Additionally,the presence of external micromolar H_(2)O_(2) also determined the elemental state on pyrrhotite surface,as it found that the contribution of Fe^(3+)and S(S^(4+)and S^(6+))species on pyrrhotite surface increased with the increase of H_(2)O_(2) concentration in the solutions,especially in the presence of Acidithiobacillus ferrooxidans.展开更多
The inefficiency of photocatalytic overall water splitting is well documented and has been extensively studied.However,a crucial aspect of this process,the side reaction,has often been overlooked.In this study,we inve...The inefficiency of photocatalytic overall water splitting is well documented and has been extensively studied.However,a crucial aspect of this process,the side reaction,has often been overlooked.In this study,we investigate the impact of side reactions on photocatalytic overall water splitting by monitoring factors such as dissolved oxygen,reactive oxygen species,and hydrogen peroxide.Further insights into the side reaction are obtained through the introduction of a platinum cocatalyst.Our findings reveal that dissolved oxygen significantly contributes to the side reaction by promoting the production of hydrogen peroxide.This byproduct is generated at the expense of electrons needed for the hydrogen evolution reaction,thereby reducing the overall efficiency of photocatalytic water splitting.This article aims to provide guidance on future research directions in the field of water splitting,with a particular emphasis on photocatalysis.展开更多
Yellowing of broccoli is a crucial limiting factor for its commercial value and consumer acceptance during postharvest.In this study,the impacts of exogenous melatonin(MEL)on chlorophyll content and fluorescence,as we...Yellowing of broccoli is a crucial limiting factor for its commercial value and consumer acceptance during postharvest.In this study,the impacts of exogenous melatonin(MEL)on chlorophyll content and fluorescence,as well as ultrastructure and membrane lipid metabolism of chloroplasts in broccoli were investigated during postharvest.The results showed that MEL treatment(200 μmol L^(-1))maintained the chlorophyll content,chloroplast autofluorescence and integral structure,and reduced the level ofserotonin in the chloroplasts in broccoli.Also,MEL treatment inhibited the membrane lipid peroxidation of chloroplasts,as indicated by low levels of superoxide anion(O_(2)^(-)),hydrogen peroxide(H_(2)O_(2))and malondialdehyde(MDA),and high levels of endogenous MEL.In addition,the stability and fluidity of chloroplast membranes were also better maintained in the treated broccoli via increasing the contents of phosphatidylglyceroland(PG),monogalactosyldiglyceride(MGDG),digalactosyldiglyceride(DGDG)and unsaturated fatty acids as well as decreasing saturated fatty acid content and the activities of lipoxygenase(LOX)and lipase(LPS).Thus,the application of MEL facilitated the maintenance of chloroplast integrity,thus contributing to yellowing postponement and the extension of the storage life of broccoli.展开更多
Catalase(CAT)is a kind of tetrameric protein in the human body,play as a key regulator for controlling oxidative stress.The main function of CAT is to regulate the concentration of hydrogen peroxide(H2O2)by catalyzing...Catalase(CAT)is a kind of tetrameric protein in the human body,play as a key regulator for controlling oxidative stress.The main function of CAT is to regulate the concentration of hydrogen peroxide(H2O2)by catalyzing the decomposition of H2O2.At present,it is reported that CAT is also involved in regulating the oxidative stress in tumor cells,and its expression level is significantly related to the development of breast cancer(BC).In addition,CAT with different expression patterns,was related in the proliferation,invasion,treatment and prognosis of BC cells.Meanwhile,BC is a common and well-known cancer among women worldwide,and its incidence has been increasing in recent years.Therefore,in-depth study of CAT in the pathogenesis and progression of BC is of great significance for the future treatment and diagnosis.The present review summarized the effects of oxidative stress on cancer cells,and emphasized the key role of CAT in the development of BC,which provides a key clue for promoting research on BC and selecting therapeutic targets.展开更多
文摘The inhibitory effect of the methanolic extract of the root of Aegle marmelos (MERA) and its constituents on the lipid peroxidation in vivo and in vitro were studied. The results suggested that MERA increased the activities of superoxide dismutase (SOD) and GSH-peroxidase in the liver cytosol of mice, but showed no significant effect on the activity of catalase, and one of its major constituents, 4-methoxy-1-methyl-2-quinolone (MMQ) increased the activity of SOD in liver tissue of mice intoxicated with FeCl2-ascorbic acid (AA)-ADP in vivo. Various constituents isolated from the root of title plant inhibited the lipid peroxidation in rat liver homogenate, which was in vitro induced by FeCl2-ascorbic acid, CCl4-NADPH, or ADP- NADPH. Of the test compounds, MMQ and its derivatives integriquinolone were similar to (-tocopherol in inhibiting MDA production in rat liver microsomes induced by Fe2+-ascorbate, CCl4-NADPH, or ADP-NADPH.
文摘This study evaluated the mechanisms of 5-fluorouracil (5-FU) induced intestinal damage by investi-gating the lipid peroxide (LPO) level, myeloperoxidase (MPO) activity and disaccharidase activity in rats.Group Ⅰ animals (n=6) were sacrificed and served as a normal control group. Group Ⅱ animaIes (n= 24 )were given a single intraperitoneal injection of 5-FU (150 mg/kg) and every 8 rats were sacrificed on day1,3 and 5 after injection respectively. Results: LPO concentration in blood and intestinal mucosa was sig-nificantly higher in the group Ⅱ than in the group Ⅰ on day 1 and 3 (P<0. 05) MPO activity was signif-icantly higher in the group I than in the group Ⅰ at different times (P<0. 01 ). Lactase activity on day 5(P<0. 01); sucrase activity (P<0. 01 and P<0. 05 respectiviely) and maltase activity (P<0. 01 ) on day3 and 5, were significantly lower in the group than in the group l. Conclusion: The results indicatethat neutrophil infiltration may be involved in 5-FU-induced lipid peroxidative damage of the small intes-tine which was reflected by the decreased disaccharidases activities.
文摘BACKGROUND Ulcerative colitis(UC)is a chronic and debilitating inflammatory bowel disease.Cumulative evidence indicates that excess hydrogen peroxide,a potent neutrophilic chemotactic agent,produced by colonic epithelial cells has a causal role leading to infiltration of neutrophils into the colonic mucosa and subsequent development of UC.This evidence-based mechanism identifies hydrogen peroxide as a therapeutic target for reducing agents in the treatment of UC.CASE SUMMARY Presented is a 41-year-old female with a 26-year history of refractory UC.Having developed steroid dependence and never achieving complete remission on treatment by conventional and advanced therapies,she began treatment with oral R-dihydrolipoic acid(RDLA),a lipid-soluble reducing agent with intracellular site of action.Within a week,rectal bleeding ceased.She was asymptomatic for three years until a highly stressful experience,when she noticed blood in her stool.RDLA was discontinued,and she began treatment with oral sodium thiosulfate pentahydrate(STS),a reducing agent with extracellular site of action.After a week,rectal bleeding ceased,and she resumed oral RDLA and discontinued STS.To date,she remains asymptomatic with normal stool calprotectin while on RDLA.CONCLUSION STS and RDLA are reducing agents that serve as highly effective and safe therapy for the induction and maintenance of remission in UC,even in patients refractory or poorly controlled by conventional and advanced therapies.Should preliminary findings be validated by subsequent clinical trials,the use of reducing agents could potentially prevent thousands of colectomies and represent a paradigm shift in the treatment of UC.
基金Supported by the National Natural Science Foundation of China (No.30371818) and Project of Key Subject Construction of Shanghai (Y0302)
文摘Objective： To study the intervention effects of Jianpi Liqi Huoxue Decoction （健脾理气活血汤, JLHD） on lipid peroxidative liver injury induced by alcohol. Methods： The rat alcoholic model of liver disease （ALD） induced by Lieber-DeCarli liquid diet was established. Thirty-two male SD rats were randomly divided into 4 groups ： the normal group （ n = 5）, the control group （ n = 9）, the model group （ n = 9） and the JLHD group （ n =9）. From the 4th week after modeling, the rats were given JLHD or distilled water by gastrogavage respectively, and the samples of blood and liver tissues were taken out from the rats for determination by the end of the 8th week. The hepatic pathological changes were observed with HE staining; the liver injury related indices, including activity of alanine aminotransferase （ALT） and aspartate aminotransferase （AST） in serum, γ-glutamyl transpeptidase （γ-GT） activity and triglyceride （TG） content in liver tissues, as well as the lipid peroxidation related indices, including malonaldehyde （MDA） content and nitric oxide synthase （NOS） activity in liver tissue, serum Fe^2＋ level, and the anti-peroxidation capacity related indices, including superoxide dismutase （SOD） activity, glutathion （GSH） content and reactive oxygen species （anti- ROS） activity in liver tissues were determined. Results： （ 1 ） There were obvious figures of fatty degeneration and inflammatory infiltration in liver tissues of the model group. As compared with the control group, in the model group, the activity of ALT and AST, and Fe^2＋ content in serum, γ-GT and NOS activity, TG and MDA content in liver tissues were significantly higher （ P〈0. 01 ）, while the activity of SOD, GSH and anti-ROS in liver tissues were significantly lower （P〈0.01）. （2） The fatty degeneration and inflammatory infiltration of liver tissues in the JLHD group were significantly lessen as compared with those in the model group; and the abnormalities of all the indexes revealed in the model rats were restored to certain extent in the JLHD group, and especially significant were the levels of ALT activity, MDA content and Fe^2＋ , which were nearly normal. Conclusion： JLHD has significant effects against alcoholic liver injury, the acting mechanism of which is likely to be related with its anti-lipid peroxidative effect.
基金supported by the National Natural Science Foundation of China,No.82071442 (to LS)a grant from the Jilin Provincial Department of Finance,No.JLSWSRCZX2021-004 (to LS)。
文摘Alzheimer's disease is an age-related neurodegenerative disorder with a complex and incompletely understood pathogenesis. Despite extensive research, a cure for Alzheimer's disease has not yet been found. Oxidative stress mediates excessive oxidative responses, and its involvement in Alzheimer's disease pathogenesis as a primary or secondary pathological event is widely accepted. As a member of the selenium-containing antioxidant enzyme family, glutathione peroxidase 4 reduces esterified phospholipid hydroperoxides to maintain cellular redox homeostasis. With the discovery of ferroptosis, the central role of glutathione peroxidase 4 in anti-lipid peroxidation in several diseases, including Alzheimer's disease, has received widespread attention. Increasing evidence suggests that glutathione peroxidase 4 expression is inhibited in the Alzheimer's disease brain, resulting in oxidative stress, inflammation, ferroptosis, and apoptosis, which are closely associated with pathological damage in Alzheimer's disease. Several therapeutic approaches, such as small molecule drugs, natural plant products, and non-pharmacological treatments, ameliorate pathological damage and cognitive function in Alzheimer's disease by promoting glutathione peroxidase 4 expression and enhancing glutathione peroxidase 4 activity. Therefore, glutathione peroxidase 4 upregulation may be a promising strategy for the treatment of Alzheimer's disease. This review provides an overview of the gene structure, biological functions, and regulatory mechanisms of glutathione peroxidase 4, a discussion on the important role of glutathione peroxidase 4 in pathological events closely related to Alzheimer's disease, and a summary of the advances in small-molecule drugs, natural plant products, and non-pharmacological therapies targeting glutathione peroxidase 4 for the treatment of Alzheimer's disease. Most prior studies on this subject used animal models, and relevant clinical studies are lacking. Future clinical trials are required to validate the therapeutic effects of strategies targeting glutathione peroxidase 4 in the treatment of Alzheimer's disease.
文摘Ulcerative colitis has baffled researchers since the early 20th century.The pre-vailing explanation attributes the chronic recurring episodes of bloody diarrhea and abdominal pain to some form of immune abnormality,despite the lack of supporting evidence.This highlights the critical need for innovative research directions and methodologies to uncover the cause and develop a cure for this disease.By analyzing existing data from less than a dozen previously published studies,a novel,evidence-based pathogenesis was constructed,implicating colonic epithelial hydrogen peroxide as a causal factor in the development of this disease.This newly identified mechanism informed the creation of a ground-breaking class of therapeutics,known as reducing agents,which have demon-strated remarkable success in resolving colonic inflammation and restoring colonic health in patients with refractory ulcerative colitis.This paper outlines the timeline of these publications and reinterprets the findings within the context of contemporary biomedical science.
基金supported by grants from the National Natural Science Foundation of China(22076104)the“Taishan Scholars”Program for Young Expert of Shandong Province(tsqn202103105).
文摘Ferroptosis,a type of programmed cell death,represents a distinct paradigm in cell biology.It is characterized by the iron-dependent accumulation of reactive oxygen species,which induce lipid peroxidation(LPO),and is orchestrated by the interplay between iron,lipid peroxides,and glutathione.In this review,we emphasize the frequently overlooked role of iron in LPO beyond the classical iron-driven Fenton reaction in several crucial processes that regulate cellular iron homeostasis,including iron intake and export as well as ferritinophagy,and the emerging roles of endoplasmic reticulum-resident flavoprotein oxidoreductases,especially P450 oxidoreductases,in modulating LPO.We summarize how various types of fatty acids(FAs),including saturated,monounsaturated,and polyunsaturated FAs,differentially influence ferroptosis when incorporated into phospholipids.Furthermore,we highlight the therapeutic potential of targeting LPO to mitigate ferroptosis and discuss the regulatory mechanisms of endogenous lipophilic radical-trapping antioxidants that confer resistance to ferroptosis,shedding light on therapeutic avenues for ferroptosis-associated diseases.
基金financial support from the National Key R&D Program of China(No.2022YFC3401003)the National Natural Science Foundation of China(Nos.21927808,82073817,22104160)。
文摘Gastric Carcinoma(GC)is a highly fatal malignant tumor with a poor prognosis.Its elevated mortality rates are primarily due to its proclivity for late-stage metastasis.Exploring the metabolic interactions between tumor microenvironment and the systemic bloodstream could help to clearly understand the mechanisms and identify precise biomarkers of tumor growth,proliferation,and metastasis.In this study,an integrative approach that combines plasma metabolomics with mass spectrometry imaging of tumor tissue was developed to investigate the global metabolic landscape of GC tumorigenesis and metastasis.The results showed that the oxidized glutathione to glutathione ratio(GSSH/GSH)became increased in non-distal metastatic GC(M0),which means an accumulation of oxidative stress in tumor tissues.Furthermore,it was found that the peroxidation of polyunsaturated fatty acids,such as 9,10-EpOMe,9-HOTrE,etc.,were accelerated in both plasma and tumor tissues of distal metastatic GC(M1).These changes were further confirmed the potential effect of CYP2E1 and GGT1 in metastatic potential of GC by mass spectrometry imaging(MSI)and immunohistochemistry(IHC).Collectively,our findings reveal the integrated multidimensional metabolomics approach is a clinical useful method to unravel the bloodtumor metabolic crosstalk,illuminate reprogrammed metabolic networks,and provide reliable circulating biomarkers.
基金Supported by Bozhou Key Research and Development Project,No.bzzc2020031.
文摘BACKGROUND Fistula-in-ano is an abnormal tunnel formation linking the anal canal with the perineum and perianal skin.Multiple imagining methods are available to evaluate it,among which magnetic resonance imaging(MRI)is the most advanced nonin-vasive preoperative method.However,it is limited in its visualization function.AIM To investigate the use of intraluminal MRI for perianal fistulas via a novel direct MRI fistulography method.METHODS We mixed 3%hydrogen peroxide(HP)with gadolinium for HPMRI fistulogra-phy,retrospectively analyzing 60 cases of complex/recurrent fistula-in-ano using physical examination,trans-perineal ultrasonography(TPUS),low-spatial-reso-lution MRI,and high-resolution direct HPMRI fistulography.We assessed detec-tion rates of fistula tracks,internal openings,their relationship with anal sphinc-ters,and perianal abscesses using statistical analyses,including interobserver agreement(Kappa statistic),and compared results with intraoperative findings.RESULTS Surgical confirmation in 60 cases showed that high-resolution direct HPMRI fis-tulography provided superior detection rates for internal openings(153)and fistula tracks(162)compared to physical exams,TPUS,and low-spatial-resolution MRI(Z>5.7,P<0.05).The effectiveness of physical examination and TPUS was also inferior to that of our method for detecting perianal abscesses(54)(Z=6.773,3.694,P<0.05),whereas that of low-spatial-resolution MRI was not significantly different(Z=1.851,P=0.06).High-resolution direct HPMRI fistulography also achieved the highest interobserver agreement(Kappa:0.89,0.85,and 0.80),while low-spatial-resolution MRI showed moderate agreement(Kappa:0.78,0.74,and 0.69).TPUS and physical examination had lower agreement(Kappa range:0.33-0.63).CONCLUSION High-resolution direct HPMRI fistulography enhances the visualization of recurrent and complex fistula-in-ano,including branched fistulas,allowing for precise planning and improved surgical outcomes.
基金financial support from the National Natural Science Foundation of China(No.22279143).
文摘Hydrogen peroxide(H_(2)O_(2))is a crucial,eco-friendly oxidizing agent with a wide range of industrial,environmental,and biomedical applications.Traditional production methods,such as the anthraquinone process,face significant challenges in terms of energy consumption and environmental impact.As a sustainable alternative,photocatalytic H_(2)O_(2) production,driven by solar energy,has emerged as a promising approach.This review discusses the key advancements in photocatalytic H_(2)O_(2) synthesis,focusing on overcoming challenges such as charge recombination,selectivity for the two-electron oxygen reduction reaction(2e^(-)ORR),and catalyst stability.Recent innovations in photocatalyst design,including high-entropy materials,single-atom catalysts,and covalent organic frameworks(COFs),have significantly enhanced efficiency and stability.Furthermore,novel strategies for optimizing charge separation,light harvesting,and mass transfer are explored.The integration of artificial intelligence and bioinspired systems holds potential for accelerating progress in this field.This review provides a comprehensive overview of current challenges and cutting-edge solutions,offering valuable insights for the development of scalable,decentralized H_(2)O_(2) production systems that contribute to a more sustainable future.
文摘Electrocatalytic hydrogen peroxide(H_(2)O_(2))production via the two-electron oxygen reduction reaction(2e−ORR)is promising,but non-metal catalysts with high selectivity are lacking.Herein,a high content of pyrrolic N doped carbon(HPNC)with small mesopores is constructed.Over 80%H_(2)O_(2) selectivity at a wide potential of 0.2–0.6 V is achieved.The finite element simulation reveals that small pore-size mesopores are beneficial to O_(2) adsorption.And in-situ characterization proves that HPNC suppresses the breakage of Osingle bondO bond and enhances the stabilization of *OOH intermediates,thus improving the 2e−ORR performance.This work highlights the combination of non-metal active sites and geometry for 2e−ORR electrocatalysis.
基金funding support from the Canadian Institutes of Health Researchsupported by a Doctoral Studentship from the Wings for Life Foundation。
文摘Extensive neurodegeneration is a hallmark of traumatic spinal cord injury (SCI) that underlies permanent sensorimotor and autonomic impairments (Alizadeh et al.,2019).Following the primary impact,the spinal cord undergoes a cascade of secondary injury mechanisms that are driven by disruption of the blood-spinal cord ba rrier,vascula r inju ry,glial reactivity,neu roinfla mmation,oxidative stress,lipid peroxidation,and glutamate excitotoxicity that culminate in neuronal and oligodendroglial cell death,demyelination,and axonal damage(Alizadeh et al.,2019).To achieve a meaningful functional recovery after SCI,regeneration of new neurons and oligodendrocytes and their successful growth and integration within the neural network are critical steps for reconstructing the damaged spinal cord tissue (Fischer et al.,2020).
基金supported by the National Natural Science Foundation of China(82270386,82070252,and 8207025)the Zhejiang Provincial Medical and Health Science and Technology Plan(2023RC020)the Zhejiang Provincial Natural Science Foundation(LR21H020001).
文摘Background:Cardiac fibrosis following myocardial infarction(MI)drives adverse ventricular remodeling and heart failure,with cardiac fibroblasts(CFs)playing a central role.Glutathione S-transferase mu 1(GSTM1)is an important member of the glutathione S-transferase(GSTs)family,which plays an important role in maintaining cell homeostasis and detoxification.This study investigated the role and mechanism of GSTM1 in post-MI fibrosis.Methods:Multi-omics approaches(proteomics/scRNA-seq)identified GSTM1 as a dysregulated target in post-MI fibroblasts.Using a murine coronary ligation model,we assessed GSTM1 dynamics via molecular profiling,such as Western blotting,immunofluorescence,and real-time quantitative polymerase chain reaction.Adeno-associated virus serotype 9(AAV9)-mediated cardiac-specific GSTM1 overexpression was achieved through systemic delivery.In vitro studies employed transforming growth factor-β(TGF-β)-stimulated primary fibroblasts with siRNA/plasmid interventions.Mechanistic insights were derived from transcriptomics and lipid peroxidation assays.Results:The expression of GSTM1 in mouse CFs after MI was significantly down-regulated at both transcriptional and protein levels.In human dilated cardiomyopathy(DCM)patients with severe heart failure,GSTM1 expression was decreased alongside aggravated fibrosis.Overexpression of GSTM1 in post-MI mice improved cardiac function,while significantly reducing infarct size and fibrosis compared with the control group.In vitro models demonstrated that GSTM1 markedly attenuated collagen secretion and activation of fibroblasts,as well as suppressed their proliferation and migration.Further studies revealed that GSTM1 overexpression significantly inhibited the generation of intracellular and mitochondrial reactive oxygen species(ROS)under pathological conditions,suggesting that GSTM1 exerts an antioxidative stress effect in post-infarction fibroblasts.Further investigation of molecular mechanisms indicated that GSTM1 may suppress the initiation and progression of fibrosis by modulating lipid metabolism and ferroptosis-related pathways.Overexpression of GSTM1 significantly reduced lipid peroxidation and free ferrous iron levels in fibroblasts and mitochondria,markedly decreased ferroptosis-related indicators,and alleviated oxidative lipid levels[such as 12-hydroxyeicosapentaenoic acid(HEPE)and 9-,10-dihydroxy octadecenoic acid(DHOME)]under fibrotic conditions.GSTM1 enhanced the phosphorylation of signal transducer and activator of transcription 3(STAT3),thereby upregulating the downstream expression of glutathione peroxidase 4(GPX4),reducing ROS production,and mitigating fibroblast activation and phenotypic transformation by inhibiting lipid peroxidation.Conclusions:This study identifies GSTM1 as a key inhibitor of fibroblast activation and cardiac fibrosis,highlighting its ability to target ferroptosis through redox regulation.AAV-mediated GSTM1 therapy demonstrates significant therapeutic potential for improving outcomes post-MI.
文摘Hydrogen peroxide(H_(2)O_(2)),as a green oxidant,plays a vital role in various applications,including environmental remediation,disinfection,and chemical synthesis[1].The conventional anthraquinone process,despite its industrial maturity and high yield,suffers from high energy consumption,carbon emissions,safety risks,and reliance on precious metals[2].Despite ongoing optimizations,a more sustainable alternative is urgently needed.The direct synthesis of hydrogen peroxide from water and oxygen has long been considered as an ideal alternative due to its theoretical 100%atom efficiency and environmental sustainability.
文摘Ferroptosis, an iron-dependent type of cell death, is being considered for new clinical treatments of malignant tumors that are difficult to treat with apoptosis inducers. Although several reports have attempted to increase the sensitivity of cells to cell death by combining ferroptosis and apoptosis inducers using a single treatment, detailed elucidation of the respective mechanisms of ferroptosis and apoptosis during cell death remains unclear. Here, we evaluated combined treatment effectiveness using the apoptosis-sensitive rat insulinoma INS-1 cell lines. DNA laddering, an indicator of camptothecin (CPT)-induced apoptosis, was abolished by adding RSL3 and ML-162, but not erastin. We found that when the cells were treated with the apoptosis inducer CPT or the ferroptosis inducer RSL3, respectively, the degree of cytotoxicity observed increased dose-dependently. However, a combined CPT and RSL3 treatment did not show a synergistic decrease in cell viability. Camptothecin did not significantly affect increases in intracellular lipid peroxidation and reactive oxygen species or increases in mitochondrial and cytoplasmic free iron levels that were induced by treatment with RSL3 alone. Moreover, deferoxamine and α-tocopherol were found to inhibit RSL3-induced cytotoxicity but did not protect against CPT or CPT and RSL3-induced cytotoxicity. Finally, the exogenous addition of tert-butyl hydroperoxide inhibited DNA ladder formation that is induced by CPT, while the addition of hydrogen peroxide or ferrous ammonium sulfate had no effect. Taken together, these results suggest that lipid peroxides generated during ferroptosis may suppress cell death induced by apoptotic mechanisms.
文摘A mesocosm-based study was conducted to assess the effect of glucose and hydrogen peroxide on periphyton communities. These chemicals have been found to be effective at controlling cyanobacteria blooms in the water column but their impact on attached communities is unknown. The experimental design included a total of 4 treatments: control (no chemicals;3 replicates);hydrogen peroxide (3 replicates);glucose alone (3 different concentrations [no replicates]);and additive glucose (3 replicates). After 34 days, mean values of chlorophyll a were lower in all experimental treatments compared to the control;mean AFDM values were lower in all treatments except the unreplicated high glucose alone treatment. In contrast, mean autotrophic index values (AFDM/chlorophyll a) were greater in all treatments compared to the control, indicating heterotrophs were more resistant to the chemical treatments than autotrophs. Periphyton community biodiversity was much lower in the additive glucose and moderate glucose alone treatments than the hydrogen peroxide and control treatments. The relative abundance of the bacteria Asticcacaulis and Sphingorhabdus responded positively to the glucose treatments, whereas relative abundance of Nevskia and Caenimonas declined in both the hydrogen peroxide and glucose treatments. In terms of relative abundance, no cyanobacteria taxa were detected among the top 20 taxa. We conclude that the autotrophic component of periphyton communities is especially vulnerable to hydrogen peroxide and glucose treatments, and that any management strategy employing these chemicals should be aware of this potential impact.
基金supported by the National Key Research and Development Program of China(No.2022YFC3203301)the Natural Science Foundation of China(No.41406098).
文摘Pyrrhotite oxidation poses a big threat to water environment duo to its high potential for generating pollutants.Hydrogen peroxide,commonly found in natural water at micromolar concentrations,possesses much more aggressive oxidation ability than oxygen and can complicate the pyrrhotite oxidation process.Here,the effects of micromolar H_(2)O_(2) on the biotic and abiotic oxidation of pyrrhotite were examined at pH 1.93 and 6.45,respectively.Pyrrhotite oxidation was much more severe in acidic solutions compared to near neutral solutions.Jarosite with a high Fe/S molar ratio was widely detected in the precipitate collected in acidic solutions,and the introduction of external H_(2)O_(2) influenced the crystallinity of jarosite.A layer of iron-deficient iron-sulfur oxide formed on the surface of pyrrhotite prevents its continuous oxidation,and the presence of Acidithiobacillus ferrooxidans enhanced this situation by promoting the release of Fe from the pyrrhotite.Additionally,the presence of external micromolar H_(2)O_(2) also determined the elemental state on pyrrhotite surface,as it found that the contribution of Fe^(3+)and S(S^(4+)and S^(6+))species on pyrrhotite surface increased with the increase of H_(2)O_(2) concentration in the solutions,especially in the presence of Acidithiobacillus ferrooxidans.
基金supported by the National Key Research and Development Program of China(No.2022YFB3803600)the National Natural Science Foundation of China(Nos.22202187,22361142704,22238009,U24A2071,and 52272290)+4 种基金the National Postdoctoral Program for Innovative Talents(No.BX2021275)the Natural Science Foundation of Hubei Province of China(No.2022CFA001)the Project funded by China Postdoctoral Science Foundation(No.2022M712957)the Postdoctoral Funding Program of Hubei Province.Chuanbiao Bie and Bicheng Zhu would like to thank the China Scholarship Council(CSC)for its financial supportsupport from Australian Research Council Discovery Early Career Award(No.DE220100429).
文摘The inefficiency of photocatalytic overall water splitting is well documented and has been extensively studied.However,a crucial aspect of this process,the side reaction,has often been overlooked.In this study,we investigate the impact of side reactions on photocatalytic overall water splitting by monitoring factors such as dissolved oxygen,reactive oxygen species,and hydrogen peroxide.Further insights into the side reaction are obtained through the introduction of a platinum cocatalyst.Our findings reveal that dissolved oxygen significantly contributes to the side reaction by promoting the production of hydrogen peroxide.This byproduct is generated at the expense of electrons needed for the hydrogen evolution reaction,thereby reducing the overall efficiency of photocatalytic water splitting.This article aims to provide guidance on future research directions in the field of water splitting,with a particular emphasis on photocatalysis.
基金supported by the National Natural Science Foundation of China(Grant No.32372408)the National Natural Science Foundation of China for Youth(Grant No.32102041).
文摘Yellowing of broccoli is a crucial limiting factor for its commercial value and consumer acceptance during postharvest.In this study,the impacts of exogenous melatonin(MEL)on chlorophyll content and fluorescence,as well as ultrastructure and membrane lipid metabolism of chloroplasts in broccoli were investigated during postharvest.The results showed that MEL treatment(200 μmol L^(-1))maintained the chlorophyll content,chloroplast autofluorescence and integral structure,and reduced the level ofserotonin in the chloroplasts in broccoli.Also,MEL treatment inhibited the membrane lipid peroxidation of chloroplasts,as indicated by low levels of superoxide anion(O_(2)^(-)),hydrogen peroxide(H_(2)O_(2))and malondialdehyde(MDA),and high levels of endogenous MEL.In addition,the stability and fluidity of chloroplast membranes were also better maintained in the treated broccoli via increasing the contents of phosphatidylglyceroland(PG),monogalactosyldiglyceride(MGDG),digalactosyldiglyceride(DGDG)and unsaturated fatty acids as well as decreasing saturated fatty acid content and the activities of lipoxygenase(LOX)and lipase(LPS).Thus,the application of MEL facilitated the maintenance of chloroplast integrity,thus contributing to yellowing postponement and the extension of the storage life of broccoli.
基金Supported by National Natural Science Foundation of China,No.82273457Natural Science Foundation of Guangdong Province,No.2023A1515012762Science and Technology Special Project of Guangdong Province,No.210715216902829.
文摘Catalase(CAT)is a kind of tetrameric protein in the human body,play as a key regulator for controlling oxidative stress.The main function of CAT is to regulate the concentration of hydrogen peroxide(H2O2)by catalyzing the decomposition of H2O2.At present,it is reported that CAT is also involved in regulating the oxidative stress in tumor cells,and its expression level is significantly related to the development of breast cancer(BC).In addition,CAT with different expression patterns,was related in the proliferation,invasion,treatment and prognosis of BC cells.Meanwhile,BC is a common and well-known cancer among women worldwide,and its incidence has been increasing in recent years.Therefore,in-depth study of CAT in the pathogenesis and progression of BC is of great significance for the future treatment and diagnosis.The present review summarized the effects of oxidative stress on cancer cells,and emphasized the key role of CAT in the development of BC,which provides a key clue for promoting research on BC and selecting therapeutic targets.
