Anti-lipid peroxidation and protection of liver mitochondria against injuries by picroside Ⅱ

AIM: To investigate the anti-lipid peroxidation and protection of liver mitochondria against injuries in mice with liver damage by picroside Ⅱ. METHODS: Three animal models of liver damage induced by carbon tetrachloride (CCl4: 0.1 mL/10 g, ip), D-galactasamine (D-GaIN: 500 mg/kg, ip) and acetaminophen (AP: 0.15 g/kg, ip) were respectively treated with various concentrations of picroside Ⅱ (5, 10, 20 mg/kg, ig). Then we chose the continuously monitoring method (recommended by International Clinical Chemistry League) to analyze serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) values, Marland method to detect the activity of manganese-superoxide dismutase (SOD) in liver mitochondria, TBA colorimetry to determine the content of malonicdialdehyde (MDA) in liver tissue, DTNB method to evaluate the activity of glutathioneperoxidase (GSH-Px) and Lowry method to detect protein level in liver tissue. Meanwhile, effects of picroside Ⅱ on the activity of ATPase and swelling extent of mitochondria in hepatocytes damaged by AP were also evaluated. RESULTS: Picroside Ⅱ could significantly prevent liver toxicity in the three models of liver damage. It decreased the high levels of ALT and AST in serum induced by the administration of CCl4, D-GaIN and AP, reduced the cellular damage of liver markedly, and appeared to be even more potent than the positive control drug of biphenyl dimethyl dicarboxylate pilules (DDB). In groups treated with different doses of picroside Ⅱ, compared to the model group, the content of MDA in serum decreased evidently, whereas the content of SOD and GSH-Px increased in a dose dependent manner, and the difference was statistically significant. Further, in the study of AP model, picroside Ⅱ inhibited AP-induced liver toxicity in mice, enhanced the activity of ATPase, improved the swelling extent of mitochondria and helped to maintain a normal balance of energy metabolism. CONCLUSION: Picroside II can evidently relieve hepatocyte injuries induced by CCI4, D-GaIN and AP, help scavenge free radicals, protect normal constructions of mitochondria membrane and enhance the activity of ATPase in mitochondria, thereby modulating the balance of liver energy metabolism, which might be part of the mechanisms of hepatoprotective effects of picroside Ⅱ.

Research progress of ferroptosis regulating lipid peroxidation and metabolism in occurrence and development of primary liver cancer

As a highly aggressive tumor,the pathophysiological mechanism of primary liver cancer has attracted much attention.In recent years,factors such as ferroptosis regulation,lipid peroxidation and metabolic abnormalities have emerged in the study of liver cancer,providing a new perspective for understanding the development of liver cancer.Ferroptosis regulation,lipid peroxidation and metabolic abnormalities play important roles in the occurrence and development of liver cancer.The regulation of ferroptosis is involved in apoptosis and necrosis,affecting cell survival and death.Lipid peroxidation promotes oxidative damage and promotes the invasion of liver cancer cells.Metabolic abnormalities,especially the disorders of glucose and lipid metabolism,directly affect the proliferation and growth of liver cancer cells.Studies of ferroptosis regulation and lipid peroxidation may help to discover new therapeutic targets and improve therapeutic outcomes.The understanding of metabolic abnormalities can provide new ideas for the prevention of liver cancer,and reduce the risk of disease by adjusting the metabolic process.This review focuses on the key roles of ferroptosis regulation,lipid peroxidation and metabolic abnormalities in this process.

Mechanisms and active substances of targeting lipid peroxidation in ferroptosis regulation

Ferroptosis is a novel form of cell death driven by iron-dependent lipid peroxidation and it is implicated in various diseases,such as liver disease,acute kidney injury,cardiovascular disease,neurodegenerative disease and cancer.Lipid-based reactive oxygen species(ROS),particularly lipid hydroperoxides in the cellular membrane can lead to membrane disruption and cell death mediated by ferroptosis.There are three necessary stages involving in the process of lipid peroxidation regulation in ferroptosis,including the synthesis of membrane phospholipids,initiation of lipid peroxidation and clearance of lipid peroxides.In this review,we summarized the molecular modulation mechanisms of lipid peroxidation in ferroptosis from the above three stages,as well as various ferroptosis modulators targeting lipid peroxidation,including commonly used products,natural bioactive compounds and selenocompounds.Collectively,these findings suggest the vital role of lipid peroxidation in ferroptosis,and targeting lipid peroxidation in ferroptosis is potential to treat ferroptosis-associated diseases.

Correction to“Research progress of ferroptosis regulating lipid peroxidation and metabolism in occurrence of primary liver cancer”

Correction to“Research progress of ferroptosis regulating lipid peroxidation and metabolism in occurrence and development of primary liver cancer”in World J Gastrointest Oncol 2024;16:2335-2349,published by Shu YJ,Lao B,and Qiu YY.In this article,we added the correct citations of images.

Ferroptosis regulating lipid peroxidation metabolism in the occurrence and development of gastric cancer

BACKGROUND Gastric cancer is one of the most common malignant tumors in the world,and its occurrence and development involve complex biological processes.Iron death,as a new cell death mode,has attracted wide attention in recent years.However,the regulatory mechanism of iron death in gastric cancer and its effect on lipid peroxidation metabolism remain unclear.AIM To explore the role of iron death in the development of gastric cancer,reveal its relationship with lipid peroxidation,and provide a new theoretical basis for revealing the molecular mechanism of the occurrence and development of gastric cancer.METHODS The process of iron death in gastric cancer cells was simulated by cell culture model,and the occurrence of iron death was detected by fluorescence microscopy and flow cytometry.The changes of gene expression related to iron death and lipid peroxidation metabolism were analyzed by high-throughput sequencing technology.In addition,a mouse model of gastric cancer was established,and the role of iron death in vivo was studied by histology and immunohistochemistry,and the level of lipid peroxidation was detected.These methods comprehensively and deeply reveal the regulatory mechanism of iron death on lipid peroxidation metabolism in the occurrence and development of gastric cancer.RESULTS Iron death was significantly activated in gastric cancer cells,and at the same time,associated lipid peroxidation levels increased significantly.Through high-throughput sequencing analysis,it was found that iron death regulated the expression of several genes related to lipid metabolism.In vivo experiments demonstrated that increased iron death in gastric cancer mice was accompanied by a significant increase in lipid peroxidation.CONCLUSION This study confirmed the important role of iron death in regulating lipid peroxidation metabolism in the occurrence and development of gastric cancer.The activation of iron death significantly increased lipid peroxidation levels,revealing its regulatory mechanism inside the cell.

Iron-chelating and anti-lipid peroxidation properties of 1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methylpyridin-4-one(CM1)in longterm iron loading β-thalassemic mice

Objective:To evaluate the iron—chelating properties and free—radical scavenging activities of1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methyIpyridin—4-one(CM1) treatment in chronic iron-loaded β-thalassemic(BKO) mice.Methods:The BKO mice were fed with a ferrocene-rich diet and were orally administered with CM1|50 mg/(kg·day)| for 6 months.Blood levels of non-transferrin hound iron,labile plasma iron.ferritin(Ft) and malondialdehyde were determined.Results:The BKO mice were fed with an iron diet for 8 months which resulted in iron overload.Interestingly,the mice showed a decrease in the non—transferrin bound iron,labile plasma iron and malondialdehyde levels,but not the Ft levels after continuous CM1 treatment.Conclusions:CM1 could be an effective oral iron chelator that can reduce iron overload and lipid peroxidation in chronic iron overload β—thalassemic mice.

Potential role and therapeutic implications of glutathione peroxidase 4 in the treatment of Alzheimer's disease

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.

Triphenylmethanol Conjugates of Triptorelin as Anti-Lipid Peroxidation Prodrugs

Antioxidants are substances that can prevent or slow damage to cells caused by free radicals, unstable molecules that the body produces as a reaction to environmental and other pressures. Free radicals may play a role in heart disease, cancer and other diseases. If the body cannot process and remove free radicals efficiently, oxidative stress can result. This can harm cells and body function. Free radicals are also known as reactive oxygen species (ROS). In this research, Triptorelin®(TRP) conjugates of triphenylmethanol derivatives (TPMs) were synthesized to evaluate their in vitro lipid peroxidation potency. Comparative lipid peroxidation assays between TRP-TPMs conjugates and the corresponding TPMs derivatives were measured using thiobarbituric reactive substance (TBARS) in a dose- and time-dependent manner following the Fenton’s pathway. Overall, TBARS decreased between 20% - 30% for the treated samples of synthesized conjugates compared to their respective control physical mixtures. These data suggest that TRP-TPMs derivatives can be used to improve the biological activity of TRP.

Effect of Chemical Gametocide EXP on Membrane Lipid Peroxidation and Protective Enzyme Activity in Rapeseed (Brassica napus)

[Objective] The aim of this study was to investigate the characteristics and mechanism of chemical emasculation in rapeseed and to provide the theoretical basis for development and utilization of new chemical gametocides.[Method] The activity of peroxidase,catalase and the content of hydrogen peroxide,malondialdehyde in leaves and flower buds of Brassica napus cultivars Qinyou No.3 and L89 induced by the chemical gametocide EXP in the course of male sterility were studied.[Result] Protective enzyme activity and the content of hydrogen peroxide,malondialdehyde in rapeseed treated with EXP changed significantly,which indicated that active oxygen metabolism was abnormal.Furthermore,there was a significant difference in the reaction degree of different cultivars and organs treated by EXP.[Conclusion] There was a correlation between the disturbance of active oxygen metabolism and the male sterility induced by chemical gametocide EXP.

Chlorophyll Fluorescence and Membrane Lipid Peroxidation in the Flag Leaves of Different High Yield Rice Variety at Late Stage of Development Under Natural Condition

With indica ( Oryza sativa L.) hybrid Shanyou 63 as control, the hybrid rice varieties including Peiai 64S/E32, Peiai 64S/9311, X07S/Zihui 100, Guangyou 881 and japonica 9516 were used to study changes of chlorophyll content, photosynthetic response to light intensity and temperature, chlorophyll fluorescence characteristics and membrane lipid peroxidation in their flag leaves at the late stage of development under natural conditions in Nanjing. The results were as follows:. primary photochemical efficiency of PS II ( F-v / F-m), quantum yield of linear electron transport of PS II (phi(PSII)), electron transfer rate (ETR) in these rice varieties decreased with their decrease of chlorophyll content during this period. This kind of impediment to energy conversion induced the transfer of excessive energy to the reducing side of PS I, hence the accumulation of O-2(radical anion) and peroxidation of membrane lipid, and resulting in the accumulation of malondialdehyde (MDA), that is the destroys of photosynthetic pigments and membranes and the consequent, premature senescence. This phenomenon is variable conspicuously in different rice varieties. Under natural condition in Nanjing, F-v/F-m, phi(PSII), ETR and quenching coefficient ( qP) in japonica 9516 tolerant to photooxidation decreased less and the conversion capacity of light energy was stable, premature senescence was unlikely, and consequently the seed-setting rate was higher. While F-v/F-m, phi(PSII), ETR and photochemical qP in Shanyou 63 sensitive to photooxidation decreased more and therefore premature senescence was easy to happen, thus the seed-setting rate and yield were all reduced. The tolerance to photooxidation and premature senescence in other hybrids derived from typical two line or three line crossing laid in the middle. From the rice breeding for super-high-yield, on the basis of the good plant-type of current rice, considering both hybrid vigor and the prevention premature senescence, it would be a notable strategy to use japonica maternal line or maternal. lines with some japonica genotype as the sterile lines in rice breeding.

Effect of Weak Light on the Peroxidation of Membrane_Lipid of Cherry Leaves

The effect of weak light on the peroxidation of membrane_lipid of one_year_old cherries ( Prunus pseudocerasus L. 'Laiyang') was studied by whole_tree shading. The results showed that the net photosynthetic rate of cherry leaves under weak light was remarkably lower; the activity peroxidase (POD) increased when light intensity decreased; the activity of catalase (CAT) showed an opposite trend, and it was positively correlated with light intensity; the activity of superoxide dismutase (SOD) increased under 366 μmol·m -2 ·s -1 and 533.8 μmol·m -2 ·s -1 light intensity, but decreased under 228.8 μmol·m -2 ·s -1 and 83.9 μmol·m -2 ·s -1 light intensity. A remarkable increase of malondialdehyde (MDA), a product of membrane_lipid peroxidation, was also observed in cherry leaves when treated with weak light, indicating more serious peroxidation in the membrane.

Protective Effects of Tea Polyphenol on Cerebral Ischemia-Reperfusion Injury in Rats and Its Scavenging Oxy-radical and Anticerebral Lipid Peroxidation Effects

AIM To study the protective effects of tea polyphenol (TP) on cerebral ischemia reperfusion injury in rats and its scavenging oxygen free radical(OFR) activities and antilipid peroxidation in vitro . METHODS Cerebral ischemia reperfusion injury was produced by bilateral ligation of the common carotid arteries with vagus nerves and reperfusion for 45 min. The mitochondrial lipid peroxidation of rat brain induced by oxygen free radical was measured by thiobarbituric acid spectrophotometry. Superoxide anion (O 2) from xanthine xanthine oxidase system and hydroxyl radical (·OH) from Fe 2+ -H 2O 2 system were determined with spectrophotometry. RESULTS During Cerebral ischemia reperfusion,TP improved the activities of superoxide dismutase ( P 【0 05), GSH peroxidase( P 【0 01) and catalase( P 【0 01), while decreasing the maiondialdchyde content in the brain( P 【0 05) and brain water content ( P 【0 01). Tea polyphenol possessed significantly scavenging effects on ·OH produced by Fenton reaction and O 2 produced by xanthine xanthine oxidase system (the IC 50 were 2 2 mmol·L -1 and 1 9 mmol·L -1 respectively). Tea polyphenol could significant inhibit the lipid peroxidation of cerbral mitochondrial membrane induced by ·OH in a concentration dependent manner. CONCLUSION The results indicate that tea polyphenol could protect the injury on cerebral ischemia reperfusion in rats for OFR, these effects may be related to its scavenging effects on oxygen free radicals and antilipid peroxidant.

Responses of Membrane Lipid Peroxidation and Endogenous Hormones of Soybean Seedlings to UV-B Radiation and Rare Earth

[ Objective] The aim was to provide strategies for development of rare earth and control of environmental pollution. [ Method] Responses of membrane lipid peroxidation and endogenous hormones of soybean seedlings to UV-B radiation and rare earth were studied through hydroponics in laboratory. [ Result] The results showed that under irradiation of UV-B（ T1-0.15 W/m^2 and T2-0.45 W/m^2）, chlorophyll and indole-3-acetic acid（IAA） contents firstly decreased during the stress phase （1 -5 d） and then increased during the restoration phase （6 -9 d） while contents of malonadialdehyde（MDA） and abscisic acid（ABA） gradually increased during the imposition of UV-B radiation （1 -5 d） and subsequently decreased during recovery from UV-B stress （6 -9 d） . With adding of La （III） with the concentration of 20 mg · L^-1 , the decline/dse trend of chlorophyll, IAA, MDA and ABA contents was slowed down during the stress period while the rise/decline speed was accelerated during the recovery period. [ Conclusion] It suggests that the regulation of La （ III ） on membrane lipid peroxidation and endogenous hormones could increase chlorophyll and IAA contents, improve the metabolism of reactive oxygen species （ ROS）, inhibit membrane lipid peroxidation, decrease the accumulation amount of ABA and alleviate injury of UV-B radiation to soybean seedlings. Further, the protective potential of La （ III ） was better under low UV-B radiation than under high one.

Characteristics of Chlorophyll Fluorescence and Membrane-lipid Peroxidation of Various High-yield Rices Under Photooxidation Conditions

Using various high-yield rices (Oryza sativa L.) such as japonica cultivar 9516, two parental line hybrid rice between subspecies with more japonica element Peiai 64/E32, Liangyoupeijiu (Peiai 64/9311), and indica hybrid rices X07S/Zihui 100, Gangyou 881, Shanyou 63 as the materials, the characteristics of chlorophyll fluorescence and membrane-lipid peroxidation of detached leaves at booting stage under photooxidation conditions were studied. In comparison with indica hybrid rice, after the photooxidation treatment, the primary photochemical efficiency of PS II (F-v/F-m), quantum yield of linear electron transport of PS II (Phi(PSII)) and photochemical quenching coefficient (qP) in japonica cultivar and hybrid rice with japonica decreased less. This indicated that high-yield rice with japonica was able to maintain higher capability of light energy conversion, resulting in the alleviation of photoinhibition. Meanwhile, the higher activities of protective enzymes such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) led to the less accumulation of endogenous active oxygen (O-(2)(radical anion), H2O2) and less content of the malondialdehyde (MDA) and the less decline of chlorophyll and protein contents, indicating a stronger tolerance to photooxidation. The changes in contents of chlorophyll and protein among various nee cultivars during photooxidation treatment were consistent with the decline of chlorophyll content from heading stage to maturation stage under natural conditions. Statistical analysis showed that there was a significant correlation between the indexes of tolerance to photooxidation and the rate of seed setting, implying that the cultivar tolerated to photooxidation had higher resistance to early aging of leaf. These results suggested that from a view of superhigh-yield breeding, considering both the utilization of heterosis and the resistance to early aging of leaf, introduction of japonica element tolerating to photooxidation into the rice sterile line (maternal plant) is a breeding strategy worthy to pay great attention to.

Effects of Water─soluble Components Isolated from Salviamilltiorrhiza on Oxygen Free Radical Generation and LipidPeroxidation

The effects of water─soluble components isolated from Salvia miltiorrhiza on oxygen free radical prodction and lipid peroxidation were estimated. Five components(10 μmol/L)were shown to inhibit superoxide anion generation by xanthine─xanthine oxidase system. It was also demonstrated that six components( 100 μmol/L) prevented H_2O_2─induced hemolysis and MDA fonnation in mouse erythrocytes.The effects of Sal A, Sal B, Sal C and Ros A were dose dependent. In Langendorff rat heart, pretreatment with Sal A 20μmol/L significantly prevented MDA production induced by 30 min reoxygenation after 45 min anoxia.The results indicated that there were also other potent antioxidant componentts in Salvia milliorrhiza besides Dphl and Pal. The protection of Sal A against myocardial anoxiareoxygenation inury may be mainly ascribed to its oxygen free radical scavenging activity.

Effects of Exogenous Nitric Oxide on Membrane Lipid Peroxidation in Wheat Seeding Exposed to Enhanced Ultraviolet-B Radiation

[Objective] Effects of different concentrations of nitric oxide on membrane lipid peroxidation of wheat induced by enhanced UV-B radiation were researched,sodium nitroprusside （SNP） was selected as an exogenous nitric oxide（NO）donor.[Method] There are 3 groups including CK,UV treatment group （B）,B＋SNP treatment group,0,1,2,3,4 d sampling after treatment respectively,and physiological and biochemical indexes of MDA content and CAT,POD,SOD and so on were determined,repeated 3 times,and statistical analyzed.[Result] The results showed that,after the enhanced UV-B radiation,activity of the catalase （CAT）,superoxide dismutase （SOD） and of the guaiacol peroxidase （POD） all reduced apparently,and the concentration of malondialdehyde （MDA） increased obviously,leading to oxidative damage in wheat seedlings.Impose different concentrations of SNP after UV-B radiation,may mitigate oxidative damage of wheat seedling from different degrees,which was in agreement with the effect of making the concentration of MDA decrease and the activity of the CAT,SOD and POD all increased.The mitigation role of 0.01 mol/L SNP was more obvious for roots＇ oxidative damage,while 0.1 mmol/L SNP is more effective for oxidative damage of leaves.[Conclusion] Exogenous NO donor SNP had obvious relieve effects on oxidative damage of wheat seedlings caused by UV-B radiation,which can enhance adaptive capacity of plants to adversity stress.

Photochemical Efficiency of PSⅡ and Membrane Lipid Peroxidation in Leaves of indica and japonica Rice (Oryza sativa) Under Chilling Temperature and Strong Light Stress Conditions

Relationships between fluorescence parameters and membrane lipid peroxidation in leaves of indica and japonica rice (Oryza sativa L.) during later growth stage were studied under chilling temperature and strong light stress conditions. Results showed that D1 protein contents of PSⅡ in photosynthetic apparatus dropped, the generation of antheraxanthin (A) and zeaxanthin (Z) of xanthophyll cycle were inhibited partly, PSⅡ photochemical efficiency (F v/F m)and non-photochemical quenching (q N) were also decreased obviously. In addition, endogenous active oxygen scavenger—superoxide dismutase (SOD) reduced, superoxide anion radical (O -· 2) and malondialdehyde (MDA) accumulated, as a result, photooxidation of leaves occurred under chilling temperature and strong light stress conditions. Obvious differences in the changes of the above mentioned physiological parameters between indica and japonica rice were observed. Experiments in leaves treated with inhibitors under chilling temperature and strong light conditions showed that indica rice was more sensitive to chilling temperature with strong light and subjected to photooxidation more than japonica rice. Notable positive correlation between D1 protein contents and F v/F m or (A+Z)/(A+Z+V), and a marked negative correlation between F v/F m and MDA contents were obtained by regression analysis in indica and japonica rice during chilling temperature and strong light conditions. According to the facts mentioned above, it was inferred that PSⅡ photochemical efficiency(F v/F m) was the key index to forecast for the prediction of photooxidation under stress circumstances and the physiological basis were the synthetic capacity of D1 protein and the protection of xanthophyll cycle.

Studies on the Anti-lipid Peroxidative Actions of the Methanolic Extract of the Root of Aegle marmelos and Its Constituents In Vivo and In Vitro

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.

Study on Antioxidants and Lipid Peroxidation from Pea Crops of Platean

[ Objective] The aim of this study was to discuss the effect of antioxidants and lipid peroxidation from pea crops of plateau. [ Method] SOD enzyme liquid from pea crops of plateau was extracted by means of protein concentration assay, enzyme activity assay and antioxidant activity determination by DPPH method, peroxide activity inhibition of in vitro tissues from mice by homogenate MDA colorimetry method and lipid peroxidation assay of in vitro tissues. [ Result ] IC50 of the crude enzyme liquid extracted from pea on DPPH was 55.16 mg/L, while the scavenging rate of the crude enzyme liquid was lower than that of ascorbic acid, tea polyphenol and citric acid with the same concentration. The synergistic effect was found in ascorbic acid and crude enzyme liquid, but the synergism of ascorbic acid was better than that of citric acid. IC50 of SOD enzyme liquid extracted from pea on DPPH was 11.1 mg/L, which was better than that of tea polyphenol and closely similar to that of ascorbic acid. SOD enzyme liquid extracted from pea had an inhibitory effect on MDA production from in vitro tissues such as liver, kidney and heart, especially for a significantly inhibitory effect on MDA from liver in vitro. When the concentration was 0.25 mg/ml, the inhibition rate reached 78.3%, and then the inhibition rate increased little with the concentration incresas, while its effect on heart and kidney were inferior. [ Conclusion] SOD crude enzyme liquid and SOD enzyme liquid extracted from pea all have certain DPPH scavenging capacity, while SOD enzyme liquid extracted from pea has an inhibitory effect on lipid peroxidation.

The Effects of Captopril and Cicaprost on Changes of Cardiac Membrane Fluidity and Lipid Peroxidation

The main purpose of this study was to investigate the protective actions of captopril and cicaprost on changes of membrane fluidity of cultured neonatal rat myocardial cells exposed to anoxia and sugar deprivation.Lipid peroxidation level estimated by determining the thiobarbituric acid reactive substance(TBARS)content and lactate dehydrogenase(LDH)released in culture medium was also observed in order to examine other membrane-related changes due to anoxia.Membrane fluidity was monitored by measuring changes in the steady state fluorescence anisotropy(r_s)by fluorescence spectroscopy.The r_s value,TBARS level and LDH release were significantly increased after 3 h anoxia.Captopril(180 μmol/L),cicaprost(30 nmol/L)and indomethacin(1μmol/L)did not alter r_s, TBARS level and LDH activity of normal cultured neonatal rat myocardial cells.However,both captopril and cicaprost significantly prevented the increases of r_s,TBARS content and LDH release in those cells exposed to anoxia and sugar deprivation.lndomethacin abolished the actions of captopril on TBARS production and LDH release,but maintained its membrane fluidity protection.These results indicate that captopril and cicaprost protect membrane fluidity and lipid peroxidation changes in anoxia- injured myocardial cells.The action mechanism of captopril may be due,in part,to stimulation of prostacyclin synthesis and/or release.