Advanced oxidation processes(AOPs)governed by peroxide activation to produce highly oxidative active species have been extensively explored for environmental remediation.Nevertheless,the low diffusion rates,inadequate...Advanced oxidation processes(AOPs)governed by peroxide activation to produce highly oxidative active species have been extensively explored for environmental remediation.Nevertheless,the low diffusion rates,inadequate interactions of the reactants,and limited active site exposure hinder treatment efficiency.Porous carbocatalysts with high specific surface area,tunable pore size,and programmable active sites demonstrate outstanding performance in activating diverse types of peroxides to generate active species for treatment of aqueous organic pollutants.The pore-rich structures enhance reaction kinetics for peroxide activation by facilitating diffusion of the reactants and their interactions.Additionally,the structural flexibility of porous structures favors the accommodation of highly dispersed metal species and allows for precise tuning of the microenvironment around the active sites,which further enhances the catalytic activity.This review critically summarizes the recent research progress in the applications of engineered porous carbocatalysts for peroxide activation and outlines the prevailing pore construction methods in carbocatalysts.Moreover,engineering strategies to regulate the mass transfer efficiency and fine-tune the microenvironment around the active sites are systematically addressed to enhance their catalytic peroxide activation performances.Challenges and future research opportunities pertaining to the design,optimization,mechanistic investigation,and practical application of porous carbocatalysts in peroxide activation are also proposed.展开更多
AIM To observe the changes in erythrocyte membrane ATPases and plasma lipid peroxides (LPO) patients with in abdominal surgery under intravenous procaine-balanced anesthesia.METHODS By determining the ATPase activitie...AIM To observe the changes in erythrocyte membrane ATPases and plasma lipid peroxides (LPO) patients with in abdominal surgery under intravenous procaine-balanced anesthesia.METHODS By determining the ATPase activities of erythrocyte membrane, effects of upper abdominal surgery under intravenous procaine-balanced anesthesia on the function of erythrocytes were observed in 15 patients undergoing cholecystectomy and gastrectomy (5 males and 10 females, aged 45.9±10.20 years and weighed 60.60kg±11.93kg). All patients were free from severe renal, hepatic, pulmonary, cardiac, metabolic and endocrinological diseases and acute infection for at least 2 weeks before surgery. Patients receiving any drug known to affect carbohydrate metabolism prior to anesthesia were excluded from the study.RESULTS Erythrocyte membrane Na+, K+-ATPase, Mg2+-ATPase, Ca2+, Mg2+-ATPase activities were not significantly changed 60min-90min after incision as compared with 30min before anesthesia, but were decreased markedly 10min and 24 hours after completion of operation (P＜0.01). Plasma lipid peroxides (LPO) were increased significantly 24 hours after surgery (P＜0.01) following an initially marked but transient reduction. Plasma LPO changes were not correlated with erythrocyte membrane ATPase activities, r=-0.0396, -0.0097 and 0.4383, respectively (P＞0.05).CONCLUSION Abdominal surgical trauma under intravenous procaine-balanced anesthesia may be associated with the decreased ATPase activities of erythrocyte membrane and increased LPO in plasma.展开更多
Correlation between the absolute configuration and the CD spectra of organic peroxides was studied by ab initio method with a mo- d el moleeule CH_3-O-O-CH_3.For P form when 0°≤θ(twist angle of C-O-O-C) <90&...Correlation between the absolute configuration and the CD spectra of organic peroxides was studied by ab initio method with a mo- d el moleeule CH_3-O-O-CH_3.For P form when 0°≤θ(twist angle of C-O-O-C) <90°, there is positive Cotton effect;when 90°<θ≤180°, there is nega- tive Cotton effect;the curve is bisignate at θ=90°.展开更多
Several mixtures,based on urea derivatives and some inorganic oxidants,including also alumina,were studied by means of ballistic mortar techniques with TNT as the reference standard.The detonation pressure(P),detonati...Several mixtures,based on urea derivatives and some inorganic oxidants,including also alumina,were studied by means of ballistic mortar techniques with TNT as the reference standard.The detonation pressure(P),detonation velocity(D),detonation energy(Q),and volume of gaseous product at standard temperature and pressure(STP),V,were calculated using EXPLO5V6.3 thermochemical code.The performance of the mixtures studied was discussed in relation to their thermal reactivity,determined by means of differential thermal analysis(DTA).It is shown that the presence of hydrogen peroxide in the form of its complex with urea(i.e.as UHP)has a positive influence on the explosive strength of the corresponding mixtures which is linked to the hydroxy-radical formation in the mixtures during their initiation reaction.These radicals might initiate(at least partially)powdered aluminum into oxidation in the CJ plane of the detonation wave.Mixtures containing UHP and magnesium are dangerous because of potential auto-ignition.展开更多
The level of lipid peroxides (LPO) and copper-zinc containing superoxide dismutase (SOD-Ⅰ) in the gastric mucosa and serum was determined in 141 samples from 25 patients after con-ventional subtotal gastrectomy (11 c...The level of lipid peroxides (LPO) and copper-zinc containing superoxide dismutase (SOD-Ⅰ) in the gastric mucosa and serum was determined in 141 samples from 25 patients after con-ventional subtotal gastrectomy (11 cases of Billroth Ⅰ and 14 cases of Billroth Ⅱ) and 11 patientsafter pylorus and antroseromuscular flap preserving gastrectomy (PAFPG).Those of 11 normal subjects were examined likewise to serve as control.It was found that:(1) The average LPO levelwas much higher and the average SOD-Ⅰ level much lower in the gastric mucosa of the patientsafter conventional subtotal gastrectomy especially the Billroth Ⅱ type than in that of those afterPAFPG.(2) In 36 specimens of stump mucosa,the average LPO level was significantly higher inthe tissue around the anastomotic ring than in that of the body of the stump;no marked differ-ence of SOD-Ⅰ level between the 2 was revealed.(3) The LPO value in the stump mucosa waspositively correlated to and the SOD-Ⅰ value negatively correlated to the pH value of gastric juice.These rindings suggest that the reation of oxygen free radicals in the stump mucosa may be influ-enced by the intragastric pH or by the type of digestive continuity reconstruction,and that thereaction of oxygen free radicals especially the lipid peroxidation may play a role in the pathogenesisof the lesions in the anastomotic stoma.展开更多
Changes in erythrocyte membrane ATPases and plasma lipid peroxides（LPO） were studiedperioperatively in 15 abdominal surgical patients under intravenous procaine-balanced anesthesia.The resultsrevealed that erythrocy...Changes in erythrocyte membrane ATPases and plasma lipid peroxides（LPO） were studiedperioperatively in 15 abdominal surgical patients under intravenous procaine-balanced anesthesia.The resultsrevealed that erythrocyte membrne Na<sup>+</sup>-K<sup>+</sup>ATPase,Mg<sup>2+</sup>ATPase and Ca<sup>2+</sup>-Mg<sup>2+</sup>ATPase activities werenot significantly changed at 60～90 min after incision as compared with 30 min before anesthesia,but weredecreased markedly at 10 rain and 24 hours after completion of operation（P【0.01）.Plasma LPO wereincreased significantly by 24 hours after surgery（P【0.01） following an initially marked but transientreduction.Plasma LPO changes were not correlated with erythrocyte membrane ATPase activities,r=-0.0396,-0.0097 and-0.4383 respeetively（P】0.05）.These correlations are suggested to be inducedby neuroendoerine responses after anesthesia and/or surgical trauma.展开更多
Simple and effective organic biosensors sensitive to organic peroxides such as 2 butanone per oxide and tertbutyl hydroperoxide are constructed by immobilizing a series of redox organic dyes and horseradish pero...Simple and effective organic biosensors sensitive to organic peroxides such as 2 butanone per oxide and tertbutyl hydroperoxide are constructed by immobilizing a series of redox organic dyes and horseradish peroxidase in Eastman AQ polymer film. The organic dyes are methylene blue, methylene green, meldola blue, new methylene blue N and N methyl phenazine methosulphate. The biosensors display high sensitivity and fast response to tertbutyl hydroperoxide and 2 butanone peroxide because of high efficiency of electron transfer between immobilized horseradish peroxidase and the electrode via the redox organic dyes. The comparison of the biosensors employing different organic dyes is made in formal potential, linear range and response time.展开更多
Oxygen limiting conditions are a common occurrence in root zones of most crop plants and can adversely affect nearly all aspects of plant growth and development including its survival. The objective of this study was ...Oxygen limiting conditions are a common occurrence in root zones of most crop plants and can adversely affect nearly all aspects of plant growth and development including its survival. The objective of this study was to determine the effectiveness of a novel redox cycling agent, vitamin K3, and various peroxides including hydrogen peroxide, calcium peroxide and magnesium peroxide in alleviating the effects of hypoxia in bean seedlings grown in nutrient culture. All the anti-hypoxic agents including vitamin K3 had a positive impact on the overall growth of bean seedlings under hypoxic conditions, but their responses were variable depending on the concentration. With regard to shoot growth, vitamin K3 (5 μM) increased the leaf area significantly, by more than 58% over the hypoxic control plants and produced the highest stem fresh weight similar to calcium peroxide (20 μM) and magnesium peroxide (10 μM). In addition, the use of vitamin K3 resulted in the highest accumulation of chlorophyll (chla + chlb) in the leaves, an increase of nearly two-fold over the hypoxic control plants. Furthermore under hypoxia, calcium peroxide (20 μM) and magnesium peroxide (10 μM) produced the highest leaf biomass (FW) followed by vitamin K3. Vitamin K3 (1 μM) also favored root growth in bean seedlings under hypoxia;it produced the largest increase in root length and root biomass (DW) similar to calcium peroxide and magnesium peroxide. Based on the overall shoot and root growth response of bean seedlings to various anti-hypoxic substances under hypoxic conditions, calcium peroxide, magnesium peroxide and vitamin K3 performed better than hydrogen peroxide. These findings show that vitamin K3 and peroxide salts are effective in alleviating hypoxic stress in bean seedlings and also, further highlight their potential for dealing with hypoxia in wide ranging situations.展开更多
Understanding of the physiological effect of post-full-bloom foliar boron combined with calcium (B+Ca) on apple (<i><span style="font-family:Verdana;">Malus</span></i> <i><sp...Understanding of the physiological effect of post-full-bloom foliar boron combined with calcium (B+Ca) on apple (<i><span style="font-family:Verdana;">Malus</span></i> <i><span style="font-family:Verdana;">domestica</span></i><span style="font-family:Verdana;">) peel tissues is envisaged to give way to the unknown mode-of-action by which these mineral regimens suppress fruit sunburn-browning incidence in orchards. Promotion of this mineral approach among growers, as a certainly cheaper alternative to mitigate fruit sunburn-browning incidence in apple orchards necessitates clear elucidation of its mode-of-action. This study investigated peel photosynthetic pigments and total peroxides (as a measure of oxidative stress) in three apple cultivars, </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Cripps Pink</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Golden Delicious</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;"> and </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Granny Smith</span><span style="font-family:Verdana;">’</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> which were treated with four B+Ca treatments varying in levels of B and Ca as well as inclusion of zinc (Zn) in one treatment. Randomized complete block design experiments with five replications were conducted at commercial farms in Western Cape, South Africa. Significant (</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> < </span><i><span style="font-family:Verdana;">0.05</span></i><span style="font-family:Verdana;">) treatment effect for major pigment aspects and total peroxides occurred in all cultivars, but with strong influence of cultivar and fruit age. For instance, effect of varying B, Ca and possible B+Ca duet-effect on photosynthetic pigments occurred in </span></span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Cripps Pink</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">, whereas the Zn-treatment was mainly responsible for significant treatment effects in both </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Golden Delicious</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;"> and </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Granny Smith</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;"> apples. Significant treatment effect for total peroxides occurred in </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Cripps Pink</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;"> and </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Granny Smith</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">, yet significant interaction effect occurred with </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Golden Delicious</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">, however, these significant results did not yield meaningful peel oxidative stress differences among the treatments. Foliar treatment differences in photochemical efficiency (Fv/Fm) w</span><span style="font-family:Verdana;">ere</span><span style="font-family:Verdana;"> not significant. The study concludes with firm evidence that foliar B+Ca treatment composition has</span><span style="font-family:Verdana;"> a</span><span style="font-family:Verdana;"> significant effect on apple peel photosynthetic pigments depending on cultivar, and Zn is not desirable in the formulation of these treatments.</span>展开更多
The accelerating rate calorimeter was applied to study the thermal hazard of two kinds of organic peroxides, i.e. methyl ethyl ketone peroxide (MEKPO) and benzoyl peroxide (BPO). And their thermal decomposition charac...The accelerating rate calorimeter was applied to study the thermal hazard of two kinds of organic peroxides, i.e. methyl ethyl ketone peroxide (MEKPO) and benzoyl peroxide (BPO). And their thermal decomposition characteristics were discussed. Meanwhile, thermal decomposition characteristics of MEKPO and BPO vvere compared. The result indicated that MEKPO is more sensitive to thermal effect than BPO. While once the thermal decomposition takes place. BPO will be more hazardous than MEKPO due to its serious pressure effect. Thermal kinetic analysis of these two kinds of organic peroxides was also taken, and the kinetic parameters for them were calculated. The study of thermal decomposition of MEKPO solution with different initial concentrations indicated that, the lower concentration MEKPO solution is, the higher onset temperature will be. And with the addition of organic solvent, it becomes more difficult for MEKPO to reach a thermal decomposition. Therefore, its thermal hazard is reduced.展开更多
Side reaction pathways are observed to occur between antioxidants and peroxide during the processing of multiple resin grades mediated by controlled peroxide-induced degradation of impact polypropylene.In the present ...Side reaction pathways are observed to occur between antioxidants and peroxide during the processing of multiple resin grades mediated by controlled peroxide-induced degradation of impact polypropylene.In the present work,the reaction mechanism and main by-products between antioxidants and peroxides were investigated.The results demonstrate that peroxides greatly accelerate the decomposition reactions,and the free radicals formed from peroxide decomposition react with,for example,the antioxidant AO1010 to produce dehydrogenation of phenyl propionic unit(s)at the a position(cinnamic acid ester moiety),which generates a conjugated system leading to the increased color of the product.It is the first time to confirm the cinnamic acid moiety's existence and report its NMR data.Further,this work confirms the dehydrogenation mechanism by comparison with different sterically hindered phenolic antioxidants.It also systematically summarizes the oxidation and degradation mechanism of AO168 and AO1010 under air and peroxide environments,respectively.Based on present study,clear guidelines are obtained to improve the quality of polymeric products,especially the appearance and stability,during product development.展开更多
Compounds of poly(ethylene-co-vinyl acetate) (EVA with vinyl acetate content 33%) with three different organic per- oxides, namely, dialkyl peroxide, peroxyester peroxide, and peroxyketal peroxide, were prepared with ...Compounds of poly(ethylene-co-vinyl acetate) (EVA with vinyl acetate content 33%) with three different organic per- oxides, namely, dialkyl peroxide, peroxyester peroxide, and peroxyketal peroxide, were prepared with a twin screws extruder and a two-roll mixing mill. The cure behavior of the EVA compounds was analyzed from rheographs, which were obtained by a moving die rheometer (MDR) at various curing temperatures between 150?C to 170?C. The effects of organic peroxides on cure behavior were examined. The dynamic curing obtained by the torque rheometer provided sufficient experimental data to show that dialkyl peroxide is not suitable because it has a high half-life temperature and its by-products can discolor the final product. Peroxyester peroxide is good for curing at temperatures in the range of 150?C to 160?C, which accomplished an ultimate cure within 5 to 8 minutes. Also, the peroxyketal peroxide has higher performance, which decreased the optimum cure time to 3 minutes. The thermal decomposition mechanism of organic peroxide was applied to explain how the cure behavior is affected by generated free radicals.展开更多
Surfactants with polyoxometalates(POMs)as polar head groups have shown fascinating self-assembly behaviors and various functional applications.However,self-assembly them into reverse micelles is still challenging owin...Surfactants with polyoxometalates(POMs)as polar head groups have shown fascinating self-assembly behaviors and various functional applications.However,self-assembly them into reverse micelles is still challenging owing to the large molecular size and intermolecular strong electrostatic repulsions of POM heads.In this work,a zwitterionic POM-based surfactant was synthesized by covalently grafting two cationic long alkyl tails onto the lacunary site of[PW_(11)O_(39)]^(7-).With decreased electrostatic repulsions and increased hydrophobic effect,the POM-based reverse micelles with an average diameter of 5 nm were obtained.Interestingly,when these reverse micelles were applied for catalyzing the oxidation of styrene,an unprecedentedβ-hydroxyl peroxide compound of 2-hydroxyl-2-phenylethan-1-tert-butylperoxide was produced in high selectivity of 95.2%.In comparison,the cetyltrimethylammonium electrostatically encapsulated POMs mainly generated the epoxides or 1,2-diols.A free radical mechanism was proposed for the oxidation reaction catalyzed by the zwitterionic POM surfactants.展开更多
The changes of sclenium metabolism, glutathione peroxidase activity and lipid peroxidescontent in the tissues of rats suffering from 30% TBSA full thickness scalding were observed in thefirst 7 days after injury. It w...The changes of sclenium metabolism, glutathione peroxidase activity and lipid peroxidescontent in the tissues of rats suffering from 30% TBSA full thickness scalding were observed in thefirst 7 days after injury. It was found that selenium content in the rat tissues decreased remarkably af-ter injury, which in turn resulted in serious reduction of glutathione peroxidasc activity and significantincrease of lipid peroxides in the scrum, crythrocytcs and liver. However the muscular tissue showedno significant changes. These facts imply that after burn injury, the body is in a state of selenium deficiency, the lossof selenium might be responsible for the reduction of anti - peroxidation ability of glutathioneperoxidase, and conscqucntly there is an increase of lipid peroxides in the tissues. Only the musculartissue is insensitive to lipid peroxidation. It is believed that the reduction of anti-peroxidation abilityof glutathione peroxidasc after bum injury might be one of the main causes to intensify, the injury re-suiting from free radicals.展开更多
The thermal decomposition temperature is one of the most important parameters to evaluate fire hazard of organic peroxide. A quantitative structure-property relationship model was proposed for estimating the thermal d...The thermal decomposition temperature is one of the most important parameters to evaluate fire hazard of organic peroxide. A quantitative structure-property relationship model was proposed for estimating the thermal decomposition temperatures of organic peroxides. The entire set of 38 organic peroxides was at random divided into a training set for model development and a prediction set for external model validation. The novel local molecular descriptors of AT1, AT2, AT3, AT4, AT5, AT6 and global molecular descriptor of ATC have been proposed in order to character organic peroxides’ molecular structures. An accurate quantitative structure-property relationship （QSPR） equation is developed for the thermal decomposition temperatures of organic peroxides. The statistical results showed that the QSPR model was obtained using the multiple linear regression （MLR） method with correlation coefficient （R）, standard deviation （S）, leave-one-out validation correlation coefficient （RCV） values of 0.9795, 6.5676 ℃ and 0.9328, respectively. The average absolute relative deviation （AARD） is only 3.86% for the experimental values. Model test by internal leave-one-out cross validation and external validation and molecular descriptor interpretation were discussed. Comparison with literature results demonstrated that novel local and global descriptors were useful molecular descriptors for predicting the thermal decomposition temperatures of organic peroxides.展开更多
Structural analogues of bicyclic peroxides belonging to the G factors family have been synthesised under Mannieh type conditions, followed by an autoxidation step furnishing exclusively the peroxide. As electron trans...Structural analogues of bicyclic peroxides belonging to the G factors family have been synthesised under Mannieh type conditions, followed by an autoxidation step furnishing exclusively the peroxide. As electron transfer from heine or free iron to peroxide is the first step in the mode of action ofartemisinin -like compound, Fe（fl） induced reduction was studied and the reactivity of the intermediate C-centered radical formed was correlated to the antimalarial activity. Dissociative electron transfer was studied by electrochemistry and allowed the evaluation of the standard reduction potentials and other pertinent thermochemical information. These bicyclic peroxides were evaluated in vitro against Plasmodium falciparum and revealed moderate to good activity.展开更多
<span style="font-family:Verdana;">The effects of each of the flavonoids;genistein (G), quercetin (Q) and</span><span style="font-family:""><span style="font-family:V...<span style="font-family:Verdana;">The effects of each of the flavonoids;genistein (G), quercetin (Q) and</span><span style="font-family:""><span style="font-family:Verdana;"> kaempferol (K) at several doses on lipid peroxides (LP) and reduced glutathione (GSH) in pooled human liver microsomes (HLMs) were investigated following the oxidative damage for 4, 6, 18 and 24 hr. HLMs (1 mg/ml) were exposed to each of the above flavonoids at 0, 5, 10, 15, 20 or 25 μM and incubated for the respective times as previously stated. Our hypothesis was that HLMs exposed to the flavonoids for the respective exposure times can decrease LP and increase GSH in HLMs to better cope with the oxidative stress. </span><span style="font-family:Verdana;">The results of our studies indicate that each of the flavonoids significantly (p < 0.01) decreased LP compared to their respective controls. The highest decrease in LP was observed for K followed by Q and G. Significant increases (p < 0.01) in GSH were observed for the flavonoid doses tested with the highest</span><span style="font-family:Verdana;"> levels observed for Q for the 24-hr. incubation. The findings suggest that the flavonoids modulate oxidative stress in HLMs by decreasing LP and such decreases in LPs may be due to the increasing and or the replenished levels of GSH in the said cells to better cope with the oxidative stress.</span></span>展开更多
A catalyst-free and additive-free ring-opening reaction of polyfluoroalkyl peroxides,triethylenediamine(DABCO),and 1,2-dichloroethane(DCE)has been developed for the defluorinative synthesis of structurally diverse pip...A catalyst-free and additive-free ring-opening reaction of polyfluoroalkyl peroxides,triethylenediamine(DABCO),and 1,2-dichloroethane(DCE)has been developed for the defluorinative synthesis of structurally diverse piperazines featuring a fluoroenone framework and a N-chloroethyl-substituent with high Z-stereoselectivity.The success of this three-component reaction is attributed to the in situ generation of an active 1-(2-chloroethyl)-1,4-diazabicyclo[2.2.2]octan-1-ium(DABCO·DCE)salt,which judiciously acts as a formal N-(2-chloroethyl)piperazine equivalent in the defluorinative coupling with less-studied aliphatic fluorinated substances.Impressively,this reaction accomplishes multi-activation of robust C(sp^(3))-F,C(sp^(3))-Cl,C(sp^(3))-O,and C(sp^(3))-N bonds in a one-pot process,offering a practical platform for the late-stage functionalization of complex molecules.Furthermore,the resulting products can not only serve as versatile building blocks for the synthesis of fluorinated heterocycles,but also undergo C—Cl bond displacement transformations with N-,O-,and S-nucleophiles.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
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
基金supports from the National Natural Science Foundation of China(Nos.22478426 and 22278436)Young Elite Scientists Sponsorship Program by BAST(No.1101020370359)Science Foundation of China University of Petroleum,Beijing(No.2462021QNXZ009)。
文摘Advanced oxidation processes(AOPs)governed by peroxide activation to produce highly oxidative active species have been extensively explored for environmental remediation.Nevertheless,the low diffusion rates,inadequate interactions of the reactants,and limited active site exposure hinder treatment efficiency.Porous carbocatalysts with high specific surface area,tunable pore size,and programmable active sites demonstrate outstanding performance in activating diverse types of peroxides to generate active species for treatment of aqueous organic pollutants.The pore-rich structures enhance reaction kinetics for peroxide activation by facilitating diffusion of the reactants and their interactions.Additionally,the structural flexibility of porous structures favors the accommodation of highly dispersed metal species and allows for precise tuning of the microenvironment around the active sites,which further enhances the catalytic activity.This review critically summarizes the recent research progress in the applications of engineered porous carbocatalysts for peroxide activation and outlines the prevailing pore construction methods in carbocatalysts.Moreover,engineering strategies to regulate the mass transfer efficiency and fine-tune the microenvironment around the active sites are systematically addressed to enhance their catalytic peroxide activation performances.Challenges and future research opportunities pertaining to the design,optimization,mechanistic investigation,and practical application of porous carbocatalysts in peroxide activation are also proposed.
文摘AIM To observe the changes in erythrocyte membrane ATPases and plasma lipid peroxides (LPO) patients with in abdominal surgery under intravenous procaine-balanced anesthesia.METHODS By determining the ATPase activities of erythrocyte membrane, effects of upper abdominal surgery under intravenous procaine-balanced anesthesia on the function of erythrocytes were observed in 15 patients undergoing cholecystectomy and gastrectomy (5 males and 10 females, aged 45.9±10.20 years and weighed 60.60kg±11.93kg). All patients were free from severe renal, hepatic, pulmonary, cardiac, metabolic and endocrinological diseases and acute infection for at least 2 weeks before surgery. Patients receiving any drug known to affect carbohydrate metabolism prior to anesthesia were excluded from the study.RESULTS Erythrocyte membrane Na+, K+-ATPase, Mg2+-ATPase, Ca2+, Mg2+-ATPase activities were not significantly changed 60min-90min after incision as compared with 30min before anesthesia, but were decreased markedly 10min and 24 hours after completion of operation (P＜0.01). Plasma lipid peroxides (LPO) were increased significantly 24 hours after surgery (P＜0.01) following an initially marked but transient reduction. Plasma LPO changes were not correlated with erythrocyte membrane ATPase activities, r=-0.0396, -0.0097 and 0.4383, respectively (P＞0.05).CONCLUSION Abdominal surgical trauma under intravenous procaine-balanced anesthesia may be associated with the decreased ATPase activities of erythrocyte membrane and increased LPO in plasma.
文摘Correlation between the absolute configuration and the CD spectra of organic peroxides was studied by ab initio method with a mo- d el moleeule CH_3-O-O-CH_3.For P form when 0°≤θ(twist angle of C-O-O-C) <90°, there is positive Cotton effect;when 90°<θ≤180°, there is nega- tive Cotton effect;the curve is bisignate at θ=90°.
基金supported by means of the financial resources of Students Grant Projects No.SGSFCHT_2016002 of the Faculty of Chemical Technology at the University of Pardubice
文摘Several mixtures,based on urea derivatives and some inorganic oxidants,including also alumina,were studied by means of ballistic mortar techniques with TNT as the reference standard.The detonation pressure(P),detonation velocity(D),detonation energy(Q),and volume of gaseous product at standard temperature and pressure(STP),V,were calculated using EXPLO5V6.3 thermochemical code.The performance of the mixtures studied was discussed in relation to their thermal reactivity,determined by means of differential thermal analysis(DTA).It is shown that the presence of hydrogen peroxide in the form of its complex with urea(i.e.as UHP)has a positive influence on the explosive strength of the corresponding mixtures which is linked to the hydroxy-radical formation in the mixtures during their initiation reaction.These radicals might initiate(at least partially)powdered aluminum into oxidation in the CJ plane of the detonation wave.Mixtures containing UHP and magnesium are dangerous because of potential auto-ignition.
文摘The level of lipid peroxides (LPO) and copper-zinc containing superoxide dismutase (SOD-Ⅰ) in the gastric mucosa and serum was determined in 141 samples from 25 patients after con-ventional subtotal gastrectomy (11 cases of Billroth Ⅰ and 14 cases of Billroth Ⅱ) and 11 patientsafter pylorus and antroseromuscular flap preserving gastrectomy (PAFPG).Those of 11 normal subjects were examined likewise to serve as control.It was found that:(1) The average LPO levelwas much higher and the average SOD-Ⅰ level much lower in the gastric mucosa of the patientsafter conventional subtotal gastrectomy especially the Billroth Ⅱ type than in that of those afterPAFPG.(2) In 36 specimens of stump mucosa,the average LPO level was significantly higher inthe tissue around the anastomotic ring than in that of the body of the stump;no marked differ-ence of SOD-Ⅰ level between the 2 was revealed.(3) The LPO value in the stump mucosa waspositively correlated to and the SOD-Ⅰ value negatively correlated to the pH value of gastric juice.These rindings suggest that the reation of oxygen free radicals in the stump mucosa may be influ-enced by the intragastric pH or by the type of digestive continuity reconstruction,and that thereaction of oxygen free radicals especially the lipid peroxidation may play a role in the pathogenesisof the lesions in the anastomotic stoma.
文摘Changes in erythrocyte membrane ATPases and plasma lipid peroxides（LPO） were studiedperioperatively in 15 abdominal surgical patients under intravenous procaine-balanced anesthesia.The resultsrevealed that erythrocyte membrne Na<sup>+</sup>-K<sup>+</sup>ATPase,Mg<sup>2+</sup>ATPase and Ca<sup>2+</sup>-Mg<sup>2+</sup>ATPase activities werenot significantly changed at 60～90 min after incision as compared with 30 min before anesthesia,but weredecreased markedly at 10 rain and 24 hours after completion of operation（P【0.01）.Plasma LPO wereincreased significantly by 24 hours after surgery（P【0.01） following an initially marked but transientreduction.Plasma LPO changes were not correlated with erythrocyte membrane ATPase activities,r=-0.0396,-0.0097 and-0.4383 respeetively（P】0.05）.These correlations are suggested to be inducedby neuroendoerine responses after anesthesia and/or surgical trauma.
文摘Simple and effective organic biosensors sensitive to organic peroxides such as 2 butanone per oxide and tertbutyl hydroperoxide are constructed by immobilizing a series of redox organic dyes and horseradish peroxidase in Eastman AQ polymer film. The organic dyes are methylene blue, methylene green, meldola blue, new methylene blue N and N methyl phenazine methosulphate. The biosensors display high sensitivity and fast response to tertbutyl hydroperoxide and 2 butanone peroxide because of high efficiency of electron transfer between immobilized horseradish peroxidase and the electrode via the redox organic dyes. The comparison of the biosensors employing different organic dyes is made in formal potential, linear range and response time.
文摘Oxygen limiting conditions are a common occurrence in root zones of most crop plants and can adversely affect nearly all aspects of plant growth and development including its survival. The objective of this study was to determine the effectiveness of a novel redox cycling agent, vitamin K3, and various peroxides including hydrogen peroxide, calcium peroxide and magnesium peroxide in alleviating the effects of hypoxia in bean seedlings grown in nutrient culture. All the anti-hypoxic agents including vitamin K3 had a positive impact on the overall growth of bean seedlings under hypoxic conditions, but their responses were variable depending on the concentration. With regard to shoot growth, vitamin K3 (5 μM) increased the leaf area significantly, by more than 58% over the hypoxic control plants and produced the highest stem fresh weight similar to calcium peroxide (20 μM) and magnesium peroxide (10 μM). In addition, the use of vitamin K3 resulted in the highest accumulation of chlorophyll (chla + chlb) in the leaves, an increase of nearly two-fold over the hypoxic control plants. Furthermore under hypoxia, calcium peroxide (20 μM) and magnesium peroxide (10 μM) produced the highest leaf biomass (FW) followed by vitamin K3. Vitamin K3 (1 μM) also favored root growth in bean seedlings under hypoxia;it produced the largest increase in root length and root biomass (DW) similar to calcium peroxide and magnesium peroxide. Based on the overall shoot and root growth response of bean seedlings to various anti-hypoxic substances under hypoxic conditions, calcium peroxide, magnesium peroxide and vitamin K3 performed better than hydrogen peroxide. These findings show that vitamin K3 and peroxide salts are effective in alleviating hypoxic stress in bean seedlings and also, further highlight their potential for dealing with hypoxia in wide ranging situations.
文摘Understanding of the physiological effect of post-full-bloom foliar boron combined with calcium (B+Ca) on apple (<i><span style="font-family:Verdana;">Malus</span></i> <i><span style="font-family:Verdana;">domestica</span></i><span style="font-family:Verdana;">) peel tissues is envisaged to give way to the unknown mode-of-action by which these mineral regimens suppress fruit sunburn-browning incidence in orchards. Promotion of this mineral approach among growers, as a certainly cheaper alternative to mitigate fruit sunburn-browning incidence in apple orchards necessitates clear elucidation of its mode-of-action. This study investigated peel photosynthetic pigments and total peroxides (as a measure of oxidative stress) in three apple cultivars, </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Cripps Pink</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Golden Delicious</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;"> and </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Granny Smith</span><span style="font-family:Verdana;">’</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> which were treated with four B+Ca treatments varying in levels of B and Ca as well as inclusion of zinc (Zn) in one treatment. Randomized complete block design experiments with five replications were conducted at commercial farms in Western Cape, South Africa. Significant (</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> < </span><i><span style="font-family:Verdana;">0.05</span></i><span style="font-family:Verdana;">) treatment effect for major pigment aspects and total peroxides occurred in all cultivars, but with strong influence of cultivar and fruit age. For instance, effect of varying B, Ca and possible B+Ca duet-effect on photosynthetic pigments occurred in </span></span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Cripps Pink</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">, whereas the Zn-treatment was mainly responsible for significant treatment effects in both </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Golden Delicious</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;"> and </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Granny Smith</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;"> apples. Significant treatment effect for total peroxides occurred in </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Cripps Pink</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;"> and </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Granny Smith</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">, yet significant interaction effect occurred with </span><span style="font-family:Verdana;">‘</span><span style="font-family:Verdana;">Golden Delicious</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">, however, these significant results did not yield meaningful peel oxidative stress differences among the treatments. Foliar treatment differences in photochemical efficiency (Fv/Fm) w</span><span style="font-family:Verdana;">ere</span><span style="font-family:Verdana;"> not significant. The study concludes with firm evidence that foliar B+Ca treatment composition has</span><span style="font-family:Verdana;"> a</span><span style="font-family:Verdana;"> significant effect on apple peel photosynthetic pigments depending on cultivar, and Zn is not desirable in the formulation of these treatments.</span>
文摘The accelerating rate calorimeter was applied to study the thermal hazard of two kinds of organic peroxides, i.e. methyl ethyl ketone peroxide (MEKPO) and benzoyl peroxide (BPO). And their thermal decomposition characteristics were discussed. Meanwhile, thermal decomposition characteristics of MEKPO and BPO vvere compared. The result indicated that MEKPO is more sensitive to thermal effect than BPO. While once the thermal decomposition takes place. BPO will be more hazardous than MEKPO due to its serious pressure effect. Thermal kinetic analysis of these two kinds of organic peroxides was also taken, and the kinetic parameters for them were calculated. The study of thermal decomposition of MEKPO solution with different initial concentrations indicated that, the lower concentration MEKPO solution is, the higher onset temperature will be. And with the addition of organic solvent, it becomes more difficult for MEKPO to reach a thermal decomposition. Therefore, its thermal hazard is reduced.
文摘Side reaction pathways are observed to occur between antioxidants and peroxide during the processing of multiple resin grades mediated by controlled peroxide-induced degradation of impact polypropylene.In the present work,the reaction mechanism and main by-products between antioxidants and peroxides were investigated.The results demonstrate that peroxides greatly accelerate the decomposition reactions,and the free radicals formed from peroxide decomposition react with,for example,the antioxidant AO1010 to produce dehydrogenation of phenyl propionic unit(s)at the a position(cinnamic acid ester moiety),which generates a conjugated system leading to the increased color of the product.It is the first time to confirm the cinnamic acid moiety's existence and report its NMR data.Further,this work confirms the dehydrogenation mechanism by comparison with different sterically hindered phenolic antioxidants.It also systematically summarizes the oxidation and degradation mechanism of AO168 and AO1010 under air and peroxide environments,respectively.Based on present study,clear guidelines are obtained to improve the quality of polymeric products,especially the appearance and stability,during product development.
文摘Compounds of poly(ethylene-co-vinyl acetate) (EVA with vinyl acetate content 33%) with three different organic per- oxides, namely, dialkyl peroxide, peroxyester peroxide, and peroxyketal peroxide, were prepared with a twin screws extruder and a two-roll mixing mill. The cure behavior of the EVA compounds was analyzed from rheographs, which were obtained by a moving die rheometer (MDR) at various curing temperatures between 150?C to 170?C. The effects of organic peroxides on cure behavior were examined. The dynamic curing obtained by the torque rheometer provided sufficient experimental data to show that dialkyl peroxide is not suitable because it has a high half-life temperature and its by-products can discolor the final product. Peroxyester peroxide is good for curing at temperatures in the range of 150?C to 160?C, which accomplished an ultimate cure within 5 to 8 minutes. Also, the peroxyketal peroxide has higher performance, which decreased the optimum cure time to 3 minutes. The thermal decomposition mechanism of organic peroxide was applied to explain how the cure behavior is affected by generated free radicals.
基金supported by the Beijing Natural Science Foundation(No.2202039)the National Natural Science Foundation of China.(Nos.22178019,22101017,U1707603,21625101,21521005,21808011)+1 种基金the National Key Research and Development Program of China(No.2017YFB0307303)the Fundamental Research Funds for the Central Universities(Nos.XK1802-6,XK1803-05,XK1902,12060093063)。
文摘Surfactants with polyoxometalates(POMs)as polar head groups have shown fascinating self-assembly behaviors and various functional applications.However,self-assembly them into reverse micelles is still challenging owing to the large molecular size and intermolecular strong electrostatic repulsions of POM heads.In this work,a zwitterionic POM-based surfactant was synthesized by covalently grafting two cationic long alkyl tails onto the lacunary site of[PW_(11)O_(39)]^(7-).With decreased electrostatic repulsions and increased hydrophobic effect,the POM-based reverse micelles with an average diameter of 5 nm were obtained.Interestingly,when these reverse micelles were applied for catalyzing the oxidation of styrene,an unprecedentedβ-hydroxyl peroxide compound of 2-hydroxyl-2-phenylethan-1-tert-butylperoxide was produced in high selectivity of 95.2%.In comparison,the cetyltrimethylammonium electrostatically encapsulated POMs mainly generated the epoxides or 1,2-diols.A free radical mechanism was proposed for the oxidation reaction catalyzed by the zwitterionic POM surfactants.
文摘The changes of sclenium metabolism, glutathione peroxidase activity and lipid peroxidescontent in the tissues of rats suffering from 30% TBSA full thickness scalding were observed in thefirst 7 days after injury. It was found that selenium content in the rat tissues decreased remarkably af-ter injury, which in turn resulted in serious reduction of glutathione peroxidasc activity and significantincrease of lipid peroxides in the scrum, crythrocytcs and liver. However the muscular tissue showedno significant changes. These facts imply that after burn injury, the body is in a state of selenium deficiency, the lossof selenium might be responsible for the reduction of anti - peroxidation ability of glutathioneperoxidase, and conscqucntly there is an increase of lipid peroxides in the tissues. Only the musculartissue is insensitive to lipid peroxidation. It is believed that the reduction of anti-peroxidation abilityof glutathione peroxidasc after bum injury might be one of the main causes to intensify, the injury re-suiting from free radicals.
基金Project(2015SK20823) supported by Science and Technology Project of Hunan Province,ChinaProject(15A001) supported by Scientific Research Fund of Hunan Provincial Education Department,China+2 种基金Project(2017CL06) supported by Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation,ChinaProject(k1403029-11) supported by Science and Technology Project of Changsha City,ChinaProject(CX2015B372) supported by the Hunan Provincial Innovation Foundation for Postgraduate,China
文摘The thermal decomposition temperature is one of the most important parameters to evaluate fire hazard of organic peroxide. A quantitative structure-property relationship model was proposed for estimating the thermal decomposition temperatures of organic peroxides. The entire set of 38 organic peroxides was at random divided into a training set for model development and a prediction set for external model validation. The novel local molecular descriptors of AT1, AT2, AT3, AT4, AT5, AT6 and global molecular descriptor of ATC have been proposed in order to character organic peroxides’ molecular structures. An accurate quantitative structure-property relationship （QSPR） equation is developed for the thermal decomposition temperatures of organic peroxides. The statistical results showed that the QSPR model was obtained using the multiple linear regression （MLR） method with correlation coefficient （R）, standard deviation （S）, leave-one-out validation correlation coefficient （RCV） values of 0.9795, 6.5676 ℃ and 0.9328, respectively. The average absolute relative deviation （AARD） is only 3.86% for the experimental values. Model test by internal leave-one-out cross validation and external validation and molecular descriptor interpretation were discussed. Comparison with literature results demonstrated that novel local and global descriptors were useful molecular descriptors for predicting the thermal decomposition temperatures of organic peroxides.
文摘Structural analogues of bicyclic peroxides belonging to the G factors family have been synthesised under Mannieh type conditions, followed by an autoxidation step furnishing exclusively the peroxide. As electron transfer from heine or free iron to peroxide is the first step in the mode of action ofartemisinin -like compound, Fe（fl） induced reduction was studied and the reactivity of the intermediate C-centered radical formed was correlated to the antimalarial activity. Dissociative electron transfer was studied by electrochemistry and allowed the evaluation of the standard reduction potentials and other pertinent thermochemical information. These bicyclic peroxides were evaluated in vitro against Plasmodium falciparum and revealed moderate to good activity.
文摘<span style="font-family:Verdana;">The effects of each of the flavonoids;genistein (G), quercetin (Q) and</span><span style="font-family:""><span style="font-family:Verdana;"> kaempferol (K) at several doses on lipid peroxides (LP) and reduced glutathione (GSH) in pooled human liver microsomes (HLMs) were investigated following the oxidative damage for 4, 6, 18 and 24 hr. HLMs (1 mg/ml) were exposed to each of the above flavonoids at 0, 5, 10, 15, 20 or 25 μM and incubated for the respective times as previously stated. Our hypothesis was that HLMs exposed to the flavonoids for the respective exposure times can decrease LP and increase GSH in HLMs to better cope with the oxidative stress. </span><span style="font-family:Verdana;">The results of our studies indicate that each of the flavonoids significantly (p < 0.01) decreased LP compared to their respective controls. The highest decrease in LP was observed for K followed by Q and G. Significant increases (p < 0.01) in GSH were observed for the flavonoid doses tested with the highest</span><span style="font-family:Verdana;"> levels observed for Q for the 24-hr. incubation. The findings suggest that the flavonoids modulate oxidative stress in HLMs by decreasing LP and such decreases in LPs may be due to the increasing and or the replenished levels of GSH in the said cells to better cope with the oxidative stress.</span></span>
基金the financial support from the National Natural Science Foundation of China(22001121)Nanjing Tech University。
文摘A catalyst-free and additive-free ring-opening reaction of polyfluoroalkyl peroxides,triethylenediamine(DABCO),and 1,2-dichloroethane(DCE)has been developed for the defluorinative synthesis of structurally diverse piperazines featuring a fluoroenone framework and a N-chloroethyl-substituent with high Z-stereoselectivity.The success of this three-component reaction is attributed to the in situ generation of an active 1-(2-chloroethyl)-1,4-diazabicyclo[2.2.2]octan-1-ium(DABCO·DCE)salt,which judiciously acts as a formal N-(2-chloroethyl)piperazine equivalent in the defluorinative coupling with less-studied aliphatic fluorinated substances.Impressively,this reaction accomplishes multi-activation of robust C(sp^(3))-F,C(sp^(3))-Cl,C(sp^(3))-O,and C(sp^(3))-N bonds in a one-pot process,offering a practical platform for the late-stage functionalization of complex molecules.Furthermore,the resulting products can not only serve as versatile building blocks for the synthesis of fluorinated heterocycles,but also undergo C—Cl bond displacement transformations with N-,O-,and S-nucleophiles.
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.
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.
