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1.
Complex polyphenols present in extravirgin olive oil are not directly absorbed, but undergo gastrointestinal biotransformation, increasing the relative amount of tyrosol (TYR) and hydroxytyrosol (HT) entering the small and large intestine. We investigated the capacity of TYR and HT to inhibit the insult of dietary lipid hydroperoxydes on the intestinal mucosa, using cultures of Caco-2, a cell line with enterocyte-like features, and studying the effect of tert-butyl hydroperoxide (TBH) treatment on specific cell membrane lipid targets. The effect of homovanillic alcohol (HVA), metabolite of HT in humans and detected as metabolite of HT in Caco-2 cells, was also evaluated. Exposure to TBH induced a significant increase of the level of MDA, the formation of fatty acid hydroperoxides and 7-ketocholesterol and the loss of α-tocopherol. Pretreatment with both HT and HVA protected Caco-2 cells from oxidative damage: there was no significant detection of oxidation products and the level of α-tocopherol was preserved. Noteworthy, TYR also exerted a protective action against fatty acids degradation. In vitro trials, where the simple phenols were tested during linoleic acid and cholesterol oxidation, gave evidence of a direct scavenging of peroxyl radicals and suggested a hydrogen atom-donating activity.  相似文献   

2.
Mussels may concentrate pollutants, with possibly significant side effects on human health. Therefore, mussels (Mytilus galloprovincialis) from two sites of the Moroccan Atlantic coast (Jorf Lasfar [JL], an industrial site, and Oualidia [OL], a vegetable‐growing area), were subjected to biochemical analyses to quantify the presence of heavy metals (Cd, Cr, and Pb) and to establish the lipid profile: fatty acid, cholesterol, oxysterol, phytosterol and phospholipid content. In addition, mussel lipid extracts known to accumulate numerous toxic components were tested on murine pancreatic β‐cells (MIN6), and their biological activities were measured with various flow cytometric and biochemical methods to determine their impacts on cell death induction, organelle dysfunctions (mitochondria, lysosomes, and peroxisomes), oxidative stress and insulin secretion. The characteristics of JL and OL lipid extracts were compared with those of commercially available mussels from Spain (SP) used for human consumption. OL and JL contained heavy metals, high amounts of phospholipids, and high levels of oxysterols; the [(unsaturated fatty acids)/(saturated fatty acids)] ratio, which can be considered a sign of environmental stress leading to lipid peroxidation, was low. On MIN6 cells, JL and OL lipid extracts were able to trigger cell death. This event was associated with overproduction of H2O2, increased catalase activity, a decreased GSH level, lipid peroxidation and stimulation of insulin secretion. These effects were not observed with SP lipid extracts. These data suggest that some components from OL and JL lipid extracts might predispose to pancreatic dysfunctions. Epidemiological studies would be needed to assess the global risk on human health and the metabolic disease incidence in a context of regular seafood consumption from the OL and JL areas. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1245–1261, 2014.  相似文献   

3.
Exposure of neurons to hydrogen peroxide (H(2)O(2)) results in oxidative stress and the activation of a cascade of intracellular toxic events resulting in oxidation, lipid peroxidation, and Ca(2+) elevation, ultimately resulting in cell death. In this study, we attempted to characterize the neuroprotective effects of phlorotannins isolated from Ecklonia cava, including phloroglucinol, eckol, triphloroethol A, eckstolonol, and dieckol, against H(2)O(2)-induced cell damage in murine hippocampus neuronal (HT22) cells. We measured the reactive oxygen species (ROS) and lipid peroxidation levels and evaluated the resultant cell death and alterations in Ca(2+)-concentrations. All phlorotannins were to scavenge intracellular ROS and repress ROS accumulation, thus preventing lipid peroxidation. Consquently, all phlorotannins reduced H(2)O(2)-induced cell death in HT22 cells. Moreover, phlorotannins inhibited H(2)O(2)-induced Ca(2+) release. This study provides a new useful strategy for preventing neuronal H(2)O(2)-induced oxidative stress.  相似文献   

4.
姜黄素对H_2O_2损伤PC12细胞的保护作用   总被引:15,自引:5,他引:15  
目的 探讨姜黄素 (curcumin ,Cur)对氧化应激损伤PC12细胞的保护作用。方法 以H2 O2 损伤PC12细胞为氧化应激损伤的模型 ,采用甲氮甲唑蓝 (3 [4 ,5 dimethylthia zol 2 yl] 2 ,5diphenyltetrazoliumbromide ,MTT)法检测细胞增殖状况 ,碘化丙啶 (Propidiumiodide,PI)染色流式细胞术(flowcytometry ,FCM )检测细胞凋亡 ,罗丹明 12 3(Rho damine12 3,Rh12 3)染色FCM检测细胞线粒体膜电位 (mito chondrialpotentialmembrane ,△Ψm) ,双氢罗丹明 12 3(Dihy drohodamine12 3,DHR)染色FCM检测细胞内活性氧 (reac tiveoxygenspecies,ROS)的含量。 结果  2 0和 4 0 μmol·L-1Cur均可使 2 5~ 4 0 0 μmol·L-1H2 O2 作用 2 4h后对PC12细胞生长的抑制率下降 ,可明显抑制 10 0和 2 0 0 μmo·L-1H2 O2 作用 2 4h后对PC12细胞凋亡的诱导作用和对PC12细胞△Ψm的降低作用 ,可明显降低 10 0和 2 0 0 μmol·L-1H2 O2 作用 12h后细胞内ROS的含量。结论 Cur对氧化应激损伤PC12细胞具有保护作用 ,其机制可能与降低细胞内ROS的含量 ,进而抑制△Ψm的降低有关。  相似文献   

5.
二氢石蒜碱对过氧化氢损伤的PC12细胞的保护作用   总被引:1,自引:0,他引:1  
目的:探讨二氢石蒜碱(DL)对H2O2诱导的PC12细胞氧化损伤的影响及其可能机制。方法:用H2O2(200μmol.L-1)处理PC12细胞建立氧化应激模型,并加入二氢石蒜碱预处理作为保护。噻唑蓝(MTT)法和乳酸脱氢酶(LDH)检测细胞存活率和细胞损伤程度,利用荧光探针DCFH-DA和JC-1分别检测细胞内活性氧(ROS)和线粒体膜电位。结果:H2O2作用于PC12细胞后,细胞存活率下降,LDH活性和ROS含量增高,线粒体膜电位降低,与正常对照组比较具有显著性差异(P<0.01);10-7~10-5mol.L-1DL预处理后,细胞存活率提高,LDH和ROS变低,线粒体膜电位回升,且在一定范围呈剂量依赖性。结论:DL对H2O2诱导PC12细胞氧化损伤具有保护作用,其作用机制可能与减少ROS产生和稳定线粒体膜电位有关。  相似文献   

6.
Three series of chromans substituted at positions 2 or 5 by catechol derivatives were synthesized, and their activity against oxidative stress induced cellular damage was studied. Specifically, the ability of the new molecules to protect cultured cells from H(2)O(2)-induced DNA damage was evaluated using single cell gel electrophoresis (comet assay), while the neuroprotective activity of the new compounds against oxidative stress induced programmed cell death was studied using glutamate-challanged hippocampal HT22 cells. The majority of the new compounds are stronger neuroprotectants than quercetin. 5-Substituted chroman analogues such as the caffeic acid amides 12 and 16 and the dihydrostilbene analogue 24 were the most potent against both H(2)O(2)- and glutamate-induced damage in Jurkat T cells and HT22 cells, respectively.  相似文献   

7.
Intraperitoneal injection of the iron-chelate, ferric-nitrilotriacetate (Fe-NTA), induces renal proximal tubular damage associated with oxidative damage in vivo. A sub-lethal dose of Fe-NTA (15 mg Fe/kg body weight) was administered IP to rats; animals were sacrificed and liver, kidney and plasma were collected 1-4 h after injection. In response to the Fe-NTA administration, there were significant time-dependent reductions of the levels of total lipids, cholesterol and total unsaturated fatty acids, and a rise in the concentrations of conjugated dienes, 7-ketocholesterol and fatty acids hydroperoxides, showing a pattern inversely correlated in plasma, kidney and liver. Cholesterol level decreased significantly from 1 h after injection in the kidney and 3-4 h in the plasma and liver of treated rats. This is the first report on cholesterol reduction and accumulated 7-ketocholesterol in the tissues of rats treated with Fe-NTA as a consequence of lipid peroxidation.  相似文献   

8.
目的探讨PDE4抑制剂咯利普兰(rolipram)对H2O2致PC12细胞氧化应激损伤的保护作用及其作用机制。方法以H2O2损伤PC12细胞为氧化应激损伤模型,MTT法检测细胞存活率;碘化丙啶(Propidium iodide,PI)染色流式细胞术检测细胞周期变化;化学比色法测定细胞清除羟自由基(·OH)和超氧阴离子自由基(O2·)的能力;以及培养上清液中的丙二醛(MDA)、谷胱甘肽(GSH)和一氧化氮(NO)含量、超氧化物歧化酶(SOD)活性。Western blot和Real-time RT-PCR检测细胞内硫氧还蛋白(Trx)和诱导型一氧化氮合酶(iNOS)的表达。结果咯利普兰能明显提高H2O2损伤的PC12细胞存活率,恢复细胞增殖;提高细胞清除·OH和O2·的能力;降低MDA和NO含量,提高GSH含量和SOD活性;使Trx蛋白和mRNA表达增加,同时下调iNOS蛋白和mRNA表达。结论咯利普兰对H2O2致PC12细胞损伤具有保护作用,其作用机制可能与提高PC12细胞的抗氧化能力相关。  相似文献   

9.
In the colorectal epithelium oxidative stress is observed endogenously in premalignant adenoma cells or induced by nutritional factors like fatty acid hydroperoxides (LOOH). Bioactive phenols like resveratrol and quercetin can quench reactive oxygen species and protect from pro-oxidative damage. Our study used colorectal adenoma and carcinoma cell lines to assess antioxidant protective effects of resveratrol and quercetin. It demonstrated that both compounds efficiently protect from oxidative stress induced by LOOH. Effective concentrations (10 microM resveratrol and 1 microM quercetin) can easily be reached in the intestinal lumen after consumption of plant foods or food supplements. Both compounds prevent LOOH-induced formation of intracellular H2O2, stimulation of cyclooxygenase-2 and vascular endothelial growth factor. For reduction of endogenous H2O2 levels in colorectal tumor cells higher antioxidant-concentrations are needed in all cell lines. Quercetin (10 microM) alone even increased H2O2 in LT97 adenoma cells and stimulated VEGF production. Resveratrol and quercetin also induced 10-30% and 40-60% cell loss respectively by apoptosis. In summary, this indicates that resveratrol and quercetin have little protective capacity in absence of exogenous stress. They are however highly efficient in protecting against nutrition induced oxidative stress damage suggesting that this constitutes the major part of their tumor protective activity.  相似文献   

10.
Reactive oxygen species (ROS) can mediate damage to cellular macromolecules and lipids. Lipid peroxidation is considered to be a major pathway by which ROS can cause tissue damage and alterations in cell membranes. Other factors affecting oxidative damage include the target molecules such as fatty acids, which are readily oxidized by ROS. Thus, lipid peroxidation may depend upon the cellular fatty acid composition. Analysis of saturated fatty acids that are present by liquid chromatography/mass spectrometry (LC/MS) is difficult because they are poorly ionized under electrospray ionization (ESI) conditions. The separation of short to very long chain saturated and unsaturated fatty acids is also very challenging when LC is employed instead of gas chromatography. The use of trimethylaminoethyl (TMAE) ester iodide derivatization has been shown previously to improve the sensitivities of saturated fatty acids in the ESI mode. A reversed-phase LC method using a diphenyl column was employed to separate 14 fatty acids as their TMAE derivatives. Stable isotope dilution LC/ESI/multiple reaction monitoring/MS methodology was then developed for the quantitative analysis of seven saturated and seven unsaturated forms of short (C14) to very long (C26) chain fatty acids as their TMAE ester iodide derivatives. This methodology has allowed the analysis of fatty acid composition from parental rat intestinal epithelial cell and rat intestinal epithelial cells transfected with cyclooxygenase-2, a model system of oxidative stress.  相似文献   

11.
The anti-aging potential of Kangen-karyu extract was investigated using the mechanisms of the cellular aging model of stress-induced premature senescence (SIPS) in TIG-1 human fibroblasts. SIPS was induced by a sublethal dose of H2O2 and chronic oxidative stress with repeat treatment of low-dose H2O2. Reactive oxygen species generation, lipid peroxidation, and senescence-associated beta-galactosidase activity were elevated in TIG-1 cells under SIPS induced by H2O2. However, Kangen-karyu extract led to significant declines in these parameters, suggesting its role in ameliorating oxidative stress-related aging. It was also observed that SIPS due to H2O2 treatment led to the loss of cell viability, whereas Kangen-karyu extract improved cell viability by attenuating H2O2-induced oxidative damage. TIG-1 cells under the condition of SIPS caused by sublethal and chronic low doses of H2O2 showed nuclear factor-kappaB (NF-kappaB) translocation to the nucleus from the cytosol, while Kangen-karyu extract inhibited NF-kappaB nuclear translocation, implying that Kangen-karyu extract could exert an anti-aging effect through NF-kappaB modulation. In addition, treatment with Kangen-karyu extract under H2O2-induced chronic oxidative stress normalized the cell cycle by reducing the number of cells in the G0/G1 phase and elevating the proportion of those in the S phase, indicating the role of Kangen-karyu extract in cell cycle regulation. On the other hand, Kangen-karyu extract did not exert such an effect on cell cycle regulation under acute oxidative stress induced by sublethal H2O2. Furthermore, treatment with Kangen-karyu extract prolonged the lifespan of TIG-1 cells under SIPS. The present study suggests that Kangen-karyu might play a therapeutic role against the aging process caused by oxidative stress.  相似文献   

12.
Celiptium is an ellipticine derivative with renal toxic side effects. It has recently been characterized as a lipid overload in proximal tubular cells where loss of total phospholipids (in particular phosphatidylethanolamine) and of polyunsaturated fatty acids are linked to the accumulation of unsaturated free fatty acids and aldehydes. A time course study of celiptium-induced peroxidative damage showed that a single dose of 40 mg/kg of celiptium induced no change in total or individual phospholipids of rat renal cortex. On the other hand, free fatty acids and thiobarbituric acid reactive substances increased as early as 1 hr after celiptium injection. 4-Hydroxynonenal (4-HNE) also increased whereas polyunsaturated fatty acids levels decreased at 6 and 24 hr. After 24 hr no change was detected in microsomal phospholipids. In contrast, the brush-border membranes showed alterations such as decrease in total phospholipids and polyunsaturated fatty acids levels accompanied by increase in aldehydes. It appears that peroxidative damage occurs in brush-border membranes of celiptium-treated rat kidneys with preferential losses of phosphatidylethanolamine (PE, 30%) and phosphatidylcholine (PC, 14%).  相似文献   

13.
Abstract: Celiptium is an ellipticine derivative with renal toxic side effects. It has recently been characterized as a lipid overload in proximal tubular cells where loss of total phospholipids (in particular phosphatidylethanolamine) and of polyunsaturated fatty acids are linked to the accumulation of unsaturated free fatty acids and aldehydes. A time course study of celiptium-induced peroxidative damage showed that a single dose of 40 mg/kg of celiptium induced no change in total or individual phospholipids of rat renal cortex. On the other hand, free fatty acids and thiobarbituric acid reactive substances increased as early as 1 hr after celiptium injection. 4-Hydroxynonenal (4-HNE) also increased whereas polyunsaturated fatty acids levels decreased at 6 and 24 hr. After 24 hr no change was detected in microsomal phospholipids. In contrast, the brush-border membranes showed alterations such as decrease in total phospholipids and polyunsaturated fatty acids levels accompanied by increase in aldehydes. It appears that peroxidative damage occurs in brush-border membranes of celiptium-treated rat kidneys with preferential losses of phosphatidylethanolamine (PE, 30%) and phosphatidylcholine (PC, 14%).  相似文献   

14.
Methyl gallate (MG) has been shown to be an effective antioxidant in a variety of acellular experiments. Accordingly, this study was designed to assess the ability of MG, extracting from Toona sinensis to protect cultured Madin-Darby canine kidney (MDCK) cells against hydrogen peroxide (H2O2)-mediated oxidative stress. Trolox, a cell permeable and water-soluble vitamin E analogue, was included for comparison. First, when MDCK cells were pretreated with MG and trolox for 1 h, followed by exposing to H2O2 (0.8 mM) for an additional hour, we found that the intracellular peroxide productions, as reflected by dichlorofluorescein (DCF) fluorescence, were shown to be decreased in a concentration-dependent manner. Furthermore, using C11-BODIPY581/591 as a lipid peroxidation probe, we also found that MG, in a concentration of 100 microM, could alleviate lipid peroxidation of the cells exposed to a short-term H2O2 treatment. In addition, MG-treated cells could prevent intracellular glutathione (GSH) from being depleted following an exposure of H2O2 (8.0 mM) for a 3 h period. Next, we also examined the effect of MG on H2O2-mediated oxidative damage to DNA. Using 8-oxoguanine as an indicator for oxidative DNA damage, we demonstrated that the percentage of MDCK cells containing 8-oxoguanine was drastically increased by exposing to H2O2 (40 mM) for 3 h. However, 8-oxoguanine contents were shown to be significantly decreased in the presence of MG prior to H2O2 exposure. Comparatively, MG was shown to be a better protective agent against oxidative damage to DNA as compared to trolox. Taken together, our data suggest that MG is effective in preventing H2O2-induced oxidative stress and DNA damage in MDCK cells. The underlying mechanisms involved scavenging of intracellular reactive oxygen species (ROS), inhibition of lipid peroxidation and prevention of intracellular GSH depletion.  相似文献   

15.
The study evaluates the protective potentials of wild rice against obesity and lipotoxicity induced by a high-fat/cholesterol diet in rats. In addition to the rats of low-fat diet group, others animals were exposed to a high-fat/cholesterol diet condition for 8 weeks. The city diet (CD) is based on the diet consumed by urban residents in modern China, which is rich in fat/cholesterol and high in carbohydrates from white rice and processed wheat starch. The chief source of dietary carbohydrates of wild rice diet (WRD) is from Chinese wild rice and other compositions are the same with CD. Rats fed CD showed elevated body and liver organ weights, lipid profiles, free fatty acids (FFA) and leptin comparable with rats fed high-fat/cholesterol diet (HFD) known to induce obesity and hyperlipidaemia in this species. However, rats consuming WRD suppressed the increase of lipid droplets accumulation, FFA, and leptin, and the decrease of lipoprotein lipase and adipose triglyceride lipase. Meanwhile, WRD prevented high-fat/cholesterol diet-induced elevation in protein expression of sterol-regulatory element binding protein-1c, and gene expression of fatty acid synthase and acetyl-CoA carboxylase. These findings indicate that wild rice as a natural food has the potentials of preventing obesity and liver lipotoxicity induced by a high-fat/cholesterol diet in rats.  相似文献   

16.
Phenolic compounds are potent antioxidants that scavenge reactive oxygen species (ROS), protecting the cells against oxidative damage. Their antioxidant capacities are governed by their structural features and the nature and physical state of the cell membrane. Our study compares the protective effects of butylated hydroxyanisole (BHA) and quercetin against the cellular injury induced by oxidative stress, and the influence of membrane cholesterol contents in their antioxidant capacities, analyzing the structural changes and cellular stability of native and cholesterol-modified erythrocytes exposed to tert-butylhydroperoxide in presence of each antioxidant. The data provide clear evidence that BHA affords better protection than quercetin against ROS generation, lipid peroxidation and lipid and GSH losses in oxidized erythrocytes. However, cellular integrity and stability are better protected by quercetin owing to the hemolytic effect of BHA. Both antioxidants suppress the alterations in membrane fluidity with similar efficiency, reducing methemoglobin formation in all oxidized erythrocytes. Membrane cholesterol depletion decreases the protection against the oxidative damage provided by both antioxidants. This lower preservation may be due to low antioxidant contents, a lower antioxidant capacity, or even to an increased oxidative damage in this membrane type as a consequence of environment modifications after cholesterol depletion.  相似文献   

17.
茯苓多糖抗肿瘤作用与机理的实验研究   总被引:54,自引:1,他引:54  
观察茯苓多糖(PPS)对小鼠肉瘤S180细胞、人白血病K562细胞体外增殖的影响,发现PPS对两种细胞的增殖均有强烈抑制作用。为探讨其抗肿瘤机理,对S180细胞膜成分进行了分析,结果显示PPS与细胞接触24h,引起细胞膜唾液酸含量升高,膜磷脂含量降低,膜磷脂脂肪酸组成发生明显改变(C20:4和C14:0降低),与对照组相比,这些变化均有显著差异(P<0.05或P<0.01);但膜胆固醇含量、膜流动性(C/P比值、U/S比值)及膜中性脂脂肪酸组成不受影响。将PPS与S180细胞膜在适当条件下一同温育,发现PPS干扰膜的肌醇磷脂代谢,明显抑制磷脂酰肌醇转换。提示PPS的抗癌机理与膜生化特性改变有关,其中对膜磷脂含量、脂肪酸组成和作为膜磷脂组分之一的肌醇磷脂代谢的影响是重要环节。  相似文献   

18.
19.
A model of rabbit tracheal epithelial (RTE) cells in primary culture was used to characterize specific and repair responses of airway epithelial cells to oxidative stress. Two well-known reactive oxygen species (ROS) generating systems were used: H(2)O(2) alone or in combination with Fe(2+) to produce the hydroxyl radical. RTE cells exhibited lipid peroxidation when exposed to H(2)O(2) + Fe(2+). Moreover, catalase (CAT) activity decreased after a 1-hour treatment in 3-day-old cultures but increased in 7-day-old cultures which have higher antioxidant enzyme activities. Superoxide dismutase (SOD) activity was never affected. In addition, RTE cells displayed a repair response leading to squamous metaplasia. H(2)O(2) + Fe(2+) treatment resulted in a time-dependent increase in the steady-state level of c-myc mRNA while c-jun and c-fos were not activated. Moreover, a chronic exposure induced the expression of the squamous phenotype characterized by the expression of the cytokeratin 13 confirmed both at the message and protein levels. RTE cells in primary culture react early to H(2)O(2) + Fe(2+) exposure by an increase in c-myc expression and by modifications in CAT activity. Further, a lipid peroxidation occurs and the tracheal epithelium evolves to squamous metaplasia.  相似文献   

20.
AIM: To investigate and compare the antioxidant activities of salvianolic acid B (SalB) and Ginkgo biloba extract (EGb 761) in aqueous solution, rat microsomes and the cellular system. METHODS: Superoxide anion (O2-.) was generated using xanthine/xanthine oxidase system and phenazine methosulate/NADH system, and the effects of SalB and EGb 761 on the generation of O2-.were achieved by spectrophotometric measurement of the product formed on reduction of nitro blue tetrazolium. Two different methods were used to assess the scavenging effects of the extracts on hydroxyl radical (. OH): HPLC method was used for quantitation of . OH by oxy-radical trapping of 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) to form DMPO-OH adducts in Fe2+-EDTA-H2O2 system. To confirm the HPLC data, .OH was also measured by spectrophotometry using a commercial detection kit. The anti-lipid peroxidation effects of the extracts in microsomes of rat brain, liver and kidney induced by ascorbate-NADPH were determined by thiobarbituric acid (TBA) method. The protective effects of the extracts on peroxide hydrogen (H2O2)-induced oxidative damage in SH-SY5Y cells were investigated by assessing cell viability assay, the level of lipid peroxidation, and the lactate dehydrogenase(LDH) release. RESULTS: Both SalB and EGb 761 were able to scavenge O2-. and . OH, inhibit lipid peroxidation of microsomes, and protect SH-SY5Y cells against H2O2-induced oxidative damage. However, the concentration of SalB was far lower than that of EGb 761 when a similar effect was obtained. CONCLUSION: The antioxidant efficiency of SalB was greater than that of EGb 761. These results suggest that SalB, like EGb 761, has promising potential in treating oxidative damage-derived neurodegenerative disorders.  相似文献   

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